Randomized Evaluation of a Remote Management Program to Improve Guideline-Directed Medical Therapy: The DRIVE Trial.

BACKGROUND: Several SGLT2i (sodium-glucose transport protein 2 inhibitors) and GLP1-RA (glucagon-like peptide-1 receptor agonists) reduce cardiovascular events and improve kidney outcomes in patients with type 2 diabetes; however, utilization remains low despite guideline recommendations. METHODS: A randomized, remote implementation trial in the Mass General Brigham network enrolled patients with type 2 diabetes with increased cardiovascular or kidney risk. Patients eligible for, but not prescribed, SGLT2i or GLP1-RA were randomly assigned to simultaneous virtual patient education with concurrent prescription of SGLT2i or GLP1-RA (ie, Simultaneous) or 2 months of virtual education followed by medication prescription (ie, Education-First) delivered by a multidisciplinary team driven by nonlicensed navigators and clinical pharmacists who prescribed SGLT2i or GLP1-RA using a standardized treatment algorithm. The primary outcome was the proportion of patients with prescriptions for either SGLT2i or GLP1-RA by 6 months. RESULTS: Between March 2021 and December 2022, 200 patients were randomized. The mean age was 66.5 years; 36.5% were female, and 22.0% were non-White. Overall, 30.0% had cardiovascular disease, 5.0% had cerebrovascular disease, and 1.5% had both. Mean estimated glomerular filtration rate was 77.9 mL/(min‧1.73 m2), and mean urine/albumin creatinine ratio was 88.6 mg/g. After 2 months, 69 of 200 (34.5%) patients received a new prescription for either SGLT2i or GLP1-RA: 53.4% of patients in the Simultaneous arm and 8.3% of patients in the Education-First arm (P<0.001). After 6 months, 128 of 200 (64.0%) received a new prescription: 69.8% of patients in the Simultaneous arm and 56.0% of patients in Education-First (P<0.001). Patient self-report of taking SGLT2i or GLP1-RA within 6 months of trial entry was similarly greater in the Simultaneous versus Education-First arm (69 of 116 [59.5%] versus 37 of 84 [44.0%]; P<0.001) Median time to first prescription was 24 (interquartile range [IQR], 13-50) versus 85 days (IQR, 65-106), respectively (P<0.001). CONCLUSIONS: In this randomized trial, a remote, team-based program identifies patients with type 2 diabetes and high cardiovascular or kidney risk, provides virtual education, prescribes SGLT2i or GLP1-RA, and improves guideline-directed medical therapy. These findings support greater utilization of virtual team-based approaches to optimize chronic disease management. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT06046560.

Rapid turnover of a pea aphid superclone mediated by thermal endurance in central Chile.

Global change drivers are imposing novel conditions on Earth's ecosystems at an unprecedented rate. Among them, biological invasions and climate change are of critical concern. It is generally thought that strictly asexual populations will be more susceptible to rapid environmental alterations due to their lack of genetic variability and, thus, of adaptive responses. In this study, we evaluated the persistence of a widely distributed asexual lineage of the alfalfa race of the pea aphid, Acyrthosiphon pisum, along a latitudinal transect of approximately 600 km in central Chile after facing environmental change for a decade. Based on microsatellite markers, we found an almost total replacement of the original aphid superclone by a new variant. Considering the unprecedented warming that this region has experienced in recent years, we experimentally evaluated the reproductive performance of these two A. pisum lineages at different thermal regimes. The new variant exhibits higher rates of population increase at warmer temperatures, and computer simulations employing a representative temperature dataset suggest that it might competitively displace the original superclone. These results support the idea of a superclone turnover mediated by differential reproductive performance under changing temperatures.

Growth of long bones in European and Japanese quail from the 13th day of incubation to day 35 post-hatch.

This study described the growth, morphometric, biomechanical, and chemical properties of the femur, tibiotarsus, and tarsometatarsus of European and Japanese quail. Analyses were performed at 13 and 15 days of incubation, at hatch, and at 4, 7, 10, 14, 21, 28, and 35 days post-hatch (n=6/subspecies/period). Bone specimens were analyzed by cone-beam computed tomography, biomechanical assays, chemical analyses, and histomorphometry. Variables were fitted by the Gompertz function and its derivative or assessed using the analysis of variance. Analysis of the derivative of Gompertz curves showed that the growth behavior of the tarsometatarsal bone was similar between quail subspecies, and the femur and tibiotarsus of European quail increased first in width and then in length, whereas the opposite occurred in Japanese quail. There was an interaction between quail subspecies and days of growth on femoral, tarsometatarsal, and tibiotarsal bone densities. Femoral and tibiotarsal cross-sectional areas were influenced by the interaction of quail subspecies and day of growth. Interaction effects were significant for breaking strength and phosphorus percentage. European and Japanese quail have different femoral and tibiotarsal growth patterns, especially in the first few days after hatching, whereas tarsometatarsal growth is similar between subspecies.

[Endoscopic-percutaneous rendezvous procedure for the management of difficult biliary tract: experience in an endoscopic center in Lima-Peru]. / Procedimiento endoscópico-percutáneo de rendezvous para el manejo de vía biliar difícil: experiencia en un centro endoscópico de Lima-Perú.

OBJECTIVES: Biliary access refractory to conventional cannulation techniques is a challenging clinical scenario for most endoscopists. The endoscopic-percutaneous rendezvous technique is an optimal alternative with high success rates and low complication rates in expert hands, however its routine use in the West, mainly in Latin America, is still limited. The aim of our study was to evaluate the feasibility, efficacy and safety of endoscopic-percutaneous rendezvous in the management of difficult biliary tract in an endoscopic center in Peru. MATERIALS AND METHODS: Descriptive study - case series type that included 21 patients, with diagnosis of difficult bile duct, all treated by endoscopic-percutaneous rendezvous between July 2017 to July 2020. We evaluated: age, gender, number of previous failed endoscopic retrograde cholangiopancreatography, associated endoscopic findings, rate of successful cannulation, rate of successful resolution of difficult choledocholithiasis, adverse events and procedure-related mortality. RESULTS: The rate of successful cannulation was 100% (21/21). There were 12 cases (57.1%) of difficult choledocholithiasis of which there was a successful resolution rate of 91.6% (11/12). The overall adverse event rate was 4.7% (1/21), which was one case of post-sphincteroplasty gastrointestinal bleeding that was successfully resolved endoscopically only. CONCLUSIONS: Endoscopic-percutaneous rendezvous performed by expert hands is feasible, safe and clinically effective for the management of the difficult bile duct in Latin America.

Growth of breast muscles in European and Japanese quail raised in meat production system: a morphological analysis.

Growth curves have been described in the quail but with no attention to the muscle composing of the breast. The description of the characteristics of growth curves to body weight and to breast muscle was the aim of this study. Morphological development of Musculus supracoracoideus and Musculus pectoralis in European and Japanese quail was assessed from the final incubation of to 35 days. Gompertz models were adjusted with maximum growth rates to body weight, breast weight, and Musculus pectoralis and supracoracoideus weight at 17.6; 22.2; 23.5, and 21.4 days. The European quail had a higher body and breast weight at maturity. Musculus supracoracoideus developed faster in both subspecies but with larger Musculus pectoralis. Both musculus had a greater number of fibers type IIA and largest fibers IIB, with quadratically increasing in fiber diameter with age in both subspecies and muscles. At 35 days, results of meat quality indicated similarity between genders and subspecies, with darker and redness breast meat in Japanese quail. In conclusion, breast weight gain was a result of type IIA and IIB fiber hypertrophy in both muscles and, despite the difference in size and aptitude, Japanese and European quail showed similar body and muscle growth patterns.

Productive performance, breast growth and digestive system development in European quail subjected to post-hatch fasting for different periods.

This study assessed the effect of different periods of post-hatch fasting on animal performance and breast and digestive system growth in European quail. Quail chicks were distributed in a completely randomized design, with four fasting periods (0, 24, 36, and 48 hs) and four replications of 40 birds per treatment. In 1 to 14-day-old chicks, weight gain decreased with increasing fasting time. Compensatory gain was observed from 15 days of age onward. Fasted quail had a lower length and relative weight of the digestive system than fed animals for up to 14 days. Histologically, the duodenal villus height was significantly lower in 3-day-old quail fasted for 36 hs than in those fasted for 48 hs, but this effect was not observed at 7 days. Scanning electron microscopy showed no differences in the small intestinal mucosa between fasted and fed birds at 3 days of age. Post-hatch fasting reduced the relative weight of the breast in quail aged 1 to 14 days but did not affect type IIa and IIb fiber diameter at 35 days. On the basis of these results, it is recommended that European quail raised for meat should not be fasted for more than 48 hs post-hatch.

Changes in the genetic composition of Myzus persicae nicotianae populations in Chile and frequency of insecticide resistance mutations.

Myzus persicae is a cosmopolitan aphid that is highly polyphagous and an important agricultural pest. The subspecies M. persicae nicotianae has been described for highly specialized phenotypes adapted to tobacco (Nicotiana tabacum). In Chile, the population of M. persicae nicotianae was originally composed of a single red genotype that did not possess insecticide resistance mutations. However, in the last decade, variation in the colour of tobacco aphids has been observed in the field. To determine whether this variation stems from the presence of new genotypes, sampling was carried out across the entire distribution of tobacco cultivation regions in Chile. The aphids collected were genotyped, and the frequency of kdr (L1014F), super-kdr (M918T), modification of acetylcholinesterase (MACE) and nicotinic acetylcholine receptor ß subunit (nAChRß) mutations associated with insecticide resistance was determined. A total of 16 new genotypes of M. persicae nicotianae were detected in Chile: four of them possessed the MACE mutation, and none of them possessed the kdr, super-kdr or nAChRß mutation. The previously described red genotype was not detected in any of the sampled fields over two seasons. These results raise questions about the mechanisms underlying changes in the genetic structure of M. persicae nicotianae populations in Chile. Future research aimed at addressing these questions could provide new insight into aphid evolution and agricultural practices.

Functional insights from the GC-poor genomes of two aphid parasitoids, Aphidius ervi and Lysiphlebus fabarum.

BACKGROUND: Parasitoid wasps have fascinating life cycles and play an important role in trophic networks, yet little is known about their genome content and function. Parasitoids that infect aphids are an important group with the potential for biological control. Their success depends on adapting to develop inside aphids and overcoming both host aphid defenses and their protective endosymbionts. RESULTS: We present the de novo genome assemblies, detailed annotation, and comparative analysis of two closely related parasitoid wasps that target pest aphids: Aphidius ervi and Lysiphlebus fabarum (Hymenoptera: Braconidae: Aphidiinae). The genomes are small (139 and 141 Mbp) and the most AT-rich reported thus far for any arthropod (GC content: 25.8 and 23.8%). This nucleotide bias is accompanied by skewed codon usage and is stronger in genes with adult-biased expression. AT-richness may be the consequence of reduced genome size, a near absence of DNA methylation, and energy efficiency. We identify missing desaturase genes, whose absence may underlie mimicry in the cuticular hydrocarbon profile of L. fabarum. We highlight key gene groups including those underlying venom composition, chemosensory perception, and sex determination, as well as potential losses in immune pathway genes. CONCLUSIONS: These findings are of fundamental interest for insect evolution and biological control applications. They provide a strong foundation for further functional studies into coevolution between parasitoids and their hosts. Both genomes are available at https://bipaa.genouest.org.

Rectal syphilis in a HIV patient from Peru.

We present the case of a 53-year-old male patient, a man who had sex with men. He described the presence of inguinal adenopathy and non-painful ulcer with indurated edges on his penis that heal spontaneously after 3 months. In the same period of time the patient presented: tenesmus, bleeding and rectal pain. In the proctoscopy was observed at the level of the rectum: deep ulcer with regular and indurated edges, ulcerated bed with abundant mucus; The rectal mucosa around the ulcer had multiple circumferential erosions 2-4 mm in diameter. The biopsy showed infiltration of lymphomonocollar cells and granulomas. The HIV ELISA test was positive, CD 4: 275 cel./uL, HIV viral load: 10 300 copies / ml, VDRL: Non-reactive, FTA-Abs: 1/10 (positive). Warthin-Starry staining was used in the rectal ulcer biopsy sample identifying spirochetes. After the administration of benzatinic Penicillin G, the symptoms and lesions in the rectal region were resolved. Likewise, antiretroviral treatment was initiated. Ulcerative and erosive proctitis is common in people living with HIV infection, however, it is rare to identify spirochetes in the biopsy sample.

[Colon Paracoccidioidomycosis in a hospital from Lima - Peru: report of 4 cases]. / Paracoccidioidomicosis colónica en un hospital de Lima - Perú: reporte de 4 casos.

Paracoccidioidomycosis is the most prevalent mycosis in South America. Mucocutaneous and lymph node involvement is the most frequent affectation of this disease in our country, with the intestinal commitment rarely reported. We report 4 cases of colonic manifestation with abdominal pain, chronic diarrhea, and weight loss. The diagnosis was made with biopsy and Gomori stain. The average age was 29 years old. The colonoscopy showed many ulcers in the ileum distal and colon. We found VIH as comorbidity in one patient.

Diagnostic and therapeutic cholangioscopy in biliary diseases: a prospective study in Peru.

INTRODUCTION: Cholangioscopy is a test that allows the evaluation of the biliary epithelium. It is used for diagnosis and management of biliary diseases. OBJECTIVES: Determine the success rate of complete removal of difficult stones with the use of laser lithotripsy through cholangioscopy as well as its complications. Determine the visual impression accuracy of bile duct injuries. MATERIALS AND METHODS: This is a prospective and descriptive study. We included 39 patients between July 2016 and July 2017 with diagnosis of difficult stones in the biliary tract and indeterminate stenosis of the biliary tract that were submitted to cholangioscopy. RESULTS: Success rate of complete removal of difficult stones was 65.3%, there was one complication. Two laser sessions were required in 4 of the 17 patients who obtained complete removal of the stones. The visual impression accuracy of lesions in the bile duct to determine malignancy coincided in all cases with the final diagnosis of the patient. CONCLUSIONS: Laser lithotripsy allows a safe and effective treatment of the difficult stones of the bile duct. Precession of visual impression of lesions in the bile duct is very high.

[Colon and rectum histoplasmosis in a patient from Peru]. / Histoplasmosis del colon y recto en un paciente de Perú.

We report a case of a male patient of 52 years old with a 3 months history of pushing, tenesmus, hematochezia, pain while defecating, lost of 18 kg of weight, fever, fecaloid and purulent discharge through an perianal hole. During the colonoscopy procedure, we found many ulcers in the ascending, transverse and descending colon.We also found an elevated lesion of about 5 cm in the rectum. We used hematoxylin - eosin and Gomori-Grocott stain in the biopsies and identified many microorganisms inside macrophages which were compatible with histoplasmosis. ELISA tests for HIV, HTLV I- II were negative. Colon and rectal histoplasmosis in an immunocompetent patient is extremely rare. There are few cases of colonic histoplasmosis reported.

Facultative endosymbionts modulate the aphid reproductive performance on wheat cultivars differing in contents of benzoxazinoids.

BACKGROUND: Facultative bacterial endosymbionts have the potential to influence the interactions between aphids, their natural enemies, and host plants. Among the facultative symbionts found in populations of the grain aphid Sitobion avenae in central Chile, the bacterium Regiella insecticola is the most prevalent. In this study, we aimed to investigate whether infected and cured aphid lineages exhibit differential responses to wheat cultivars containing varying levels of the benzoxazinoid DIMBOA (2,4-dihydroxy-7-methoxy-2H-1,4-benzoxazin-3(4H)-one), which is a xenobiotic compound produced by plants. Specifically, we examined the reproductive performance responses of the most frequently encountered genotypes of Sitobion avenae when reared on wheat seedlings expressing low, medium, and high concentrations of DIMBOA. RESULTS: Our findings reveal that the intrinsic rate of population increase (rm ) in cured lineages of Sitobion avenae genotypes exhibits a biphasic pattern, characterized by the lowest rm and an extended time to first reproduction on wheat seedlings with medium levels of DIMBOA. In contrast, the aphid genotypes harbouring Regiella insecticola display idiosyncratic responses, with the two most prevalent genotypes demonstrating improved performance on seedlings featuring an intermediate content of DIMBOA compared to their cured counterparts. CONCLUSION: This study represents the first investigation into the mediating impact of facultative endosymbionts on aphid performance in plants exhibiting varying DIMBOA contents. These findings present exciting prospects for identifying novel targets for aphid control by manipulating the presence of aphid symbionts. © 2023 Society of Chemical Industry.

Water deficit and aphid resilience on wheat: examining Sitobion avenae F. and their bacterial symbionts interplay under controlled laboratory conditions.

BACKGROUND: Climate change has far-reaching effects on food security and agriculture, affecting crop yields and food distribution. Agriculture relies heavily on water for irrigation and production, making it vulnerable to water scarcity. Additionally, climate change can affect crop pest insects, leading to increased global crop losses, particularly in cereals, an important component of the human diet. Aphids are major crop pests and have a symbiotic relationship with bacterial endosymbionts that can contribute to their success as pests under a climate change scenario. To test the effect of drought on aphids, we examined varying levels of water deficit and endosymbiont composition on the grain aphid (Sitobion avenae) performance on wheat under controlled laboratory conditions. We measured the intrinsic rate of population increase (rm), the body weight of adult aphids, and the pre-reproductive period for different genotypes of the grain aphid (including Chilean superclones) under different irrigation regimes. We also analyzed the relative abundance of their endosymbionts under the different water treatments. RESULTS: Our findings revealed that water deficit affects each aphid genotype differently, impacting various traits. For instance, the body weight of adult aphids was notably affected by different water treatments, with aphids grown under intermediate water deficit (IW) being significantly bigger. The relative abundance of endosymbionts also varied among genotypes and water treatments-specifically Regiella insecticola had a noticeably higher abundance under IW (P < 0.05). CONCLUSION: This study provides valuable insights into the impact of water deficit on aphid performance and the role of endosymbionts in mitigating the effects of water deficit. © 2024 Society of Chemical Industry.

Survey of resistance to four insecticides and their associated mechanisms in different genotypes of the green peach aphid (Hemiptera: Aphididae) from Chile.

The green peach aphid, Myzus persicae (Sulzer) (Hemiptera: Aphididae) is amajor pest of agriculture worldwide that has proved to be particularly adept at evolving insecticide resistance. Several mechanisms that confer resistance to many insecticide types have been described in M. persicae. We measured the resistance status of nine multilocus genotypes (MLGs) of this aphid species collected in Chile. MLGs were identified using microsatellite markers, and these MLG clonal populations were measured for the presence of modified acetylcholinesterase (MACE), kdr and super kdr mutations, and enhanced carboxyl esterase activity. Toxicological bioassays were used to estimate aphid LC50 when treated with metamidophos (organophosphate), pirimicarb (dimethyl carbamate), cyfluthrin (pyrethroid), and imidacloprid (neonicotinoid). Two MLGs presented >20-fold resistance to pirimicarb, which was associated with the MACE mutation in the heterozygous condition. The kdr mutation was found in only four MLGs in the heterozygous condition and they showed resistance ratios (RR) to cyfluthrin of less than sevenfold. The super kdr mutation was not detected. Enhanced carboxyl esterase activity was predominantly found in the susceptible (S) to first level of resistance (R1) with RR to metamidophos less than eight-fold. Finally, RR to imidacloprid was also less than eight-fold in all MLGs tested. A few MLGs with resistance to pirimicarb were found, while susceptibility to cyfluthrin, metamidophos and imidacloprid was still predominant. A significant positive correlation between imidacloprid tolerance with pirimicarb resistance was detected, as well as between imidacloprid and metamidophos tolerance. With the increase in the use of neonicotinoid insecticides, better rotation of insecticides with different modes of action will be necessary to prevent further development of M. persicae insecticide resistance in Chile.

Neuro-Behcet's syndrome: Case report and literature review.

Behcet's disease (BD) is a multisystem, autoimmune vasculitis disorder affecting small, medium, and large blood vessels, with poorly understood pathogenesis. It commonly presents with recurrent aphthous ulcers, genital ulcers, skin lesions, and bilateral uveitis. Neurological symptoms are present in less than 10% of cases and develop, on average, 5-6 years after the first non-neurological symptoms. This presentation, known as Neuro-Behcet's disease (NBD), is associated with a worse prognosis of BD. Treatment for NBD is dependent on the severity of symptoms and the presence of other systemic manifestations but often initially involves glucocorticoids and a disease-modifying agent. This case report presents a 44-year-old female patient, previously diagnosed with BD, who presented with neurological symptoms and MRI findings consistent with NBD.

Target site mutations underlying insecticide resistance in Tunisian populations of Myzus persicae (Sulzer) on peach orchards and potato crops.

BACKGROUND: The massive use of synthetic insecticides strongly affects the level of insecticide resistance in populations of Myzus persicae worldwide. The selection of target site insensitivity-mutations is particularly worrying in areas where agro-industrial crops are vulnerable to the attacks of aphids that vector viruses, as in the case of Tunisia. Knowledge of the resistance mechanisms evolved locally in this aphid pest is a prerequisite to improving and retaining the sustainability of integrated pest management strategies. RESULTS: Target site mutations were surveyed in several populations of M. persicae collected from peach and potato crops between 2011 and 2017 in three Tunisian regions using real-time allele-specific PCR. The L1014F mutation (kdr locus) was found at a moderate frequency mostly in the heterozygous state and the homozygous resistant genotype was very uncommon. The M918T mutation (super-kdr locus) was present in a few heterozygous individuals, whereas the M918L mutation was detected for the first time in Tunisia and extreme North Africa. This latter mutation was shown to be widespread and well-established in Tunisia mainly as homozygous individuals, and was more abundant on peach than on potato crops. The S431F mutation (MACE) was found in a few heterozygous individuals. No individuals carrying the R81T mutation linked to neonicotinoid resistance were detected. CONCLUSION: This study points out a critical situation for the efficacy of pyrethroid insecticides to control M. persicae populations in Tunisia. It also confirms the rapid spread of the M918L mutation which has been detected in many different areas of the Mediterranean basin. © 2022 Society of Chemical Industry.

A mutation increases the specificity to plant compounds in an insect chemosensory protein.

Host plant recognition are highly dependent on chemosensory perception, which involves chemosensory proteins (CSPs) that bind key chemical compounds the host plants. In this work, we hypothesize that two closely related aphid taxa, which differ in diet breadth, also differ in their CSPs. We detected a non-synonymous difference (lysine for asparagine) between M. persicae sensu stricto (Mpp) and the subspecies M. p. nicotianae (Mpn) in the sequence of a CSP (CSP5). We modeled in silico the binding capacity of both CSP5s variants with 163 different potential ligands from their host plants (120 unique from tobacco, 29 unique from peach, and 14 common ligands). After docking analysis with all ligands, we selected the three best ligands for each variant to perform molecular dynamics (tobacco: 2-cyclopentene-1,4-dione, salicylaldehyde, and benzoic acid; peach: phenol, valeric acid, and benzonitrile). The binding energy of the MpnCSP5 model to the studied ligands was, in all cases, lower than with the MppCSP5 model. The ligands from the host plants showed more stable binding with MpnCSP5 than with MppCSP5. This result suggests that the set of CSPs studied among M. persicae s. str. and M. p. nicotianae are very similar, but focusing on the CSP5 protein, we found a single key mutation that increases affinities for host compounds for M. p. nicotianae, which might have contributed to the specialization to tobacco. This study provides new insights into an evolutionary trend toward specificity in a binding protein.

Genome sequencing of a predominant clonal lineage of the grain aphid Sitobion avenae.

The English grain aphid, Sitobion avenae, is a cosmopolitan pest that feeds on cereals, provoking substantial yield losses by injuring plant tissue and by vectoring plant viruses. Here we report a highly complete, de novo draft genome of the grain aphid using long-read sequencing. We generated an assembly of 2740 contigs with a N50 of 450 kb. We compared this draft genome with that of other aphid species, inspecting gene family evolution, genome-wide positive selection, and searched for horizontal gene transfer events. In addition, we described a recent copy number variant expansion of gene families involving aconitase, ABC transporter, and esterase genes that could be associated with resistance to insecticides and plant chemical defenses. This S. avenae genome obtained from a predominant invasive genotype can provide a framework for studying the spatial-temporal success of these clonal lineages in invaded agroecosystems.

Sub-Lethal Effects of λ-Cyhalothrin on Behavior and Development of the Parasitoid Aphidius colemani (Hymenoptera: Braconidae) on kdr-Resistant and Susceptible Green Peach Aphid, Myzus persicae (Hemiptera: Aphididae).

The green peach aphid, Myzus persicae (Sulzer), is a pest mainly controlled with insecticides, and it can acquire resistance through different mechanisms. Pyrethroids can select the knock down resistance (kdr) mutation in M. persicae and can also produce lethal and sub-lethal effects on its main parasitoid, Aphidius colemani Viereck. However, kdr-resistant M. persicae exhibits a reduced response to alarm pheromone and increased vulnerability to natural enemies. To study the effects of sub-lethal concentrations of a pyrethroid on the aphid-parasitoid interaction, kdr-resistant and susceptible M. persicae were confronted with A. colemani with residual sub-lethal concentrations of λ-cyhalothrin. The behavior, survival, and development of parasitoids were evaluated after exposure to λ-cyhalothrin LC20 for adult parasitoids (0.52 mg/liter) for susceptible (Mp-SS, 0.56 mg/liter) and kdr-resistant M. persicae (Mp-RR, 12.15 mg/liter). The foraging and oviposition behaviors of the parasitoids were not affected by the lower parasitoid or Mp-SS LC20. Conversely, the higher Mp-RR LC20 significantly reduced parasitoid walking, the frequency of sting attempts, and successful stings, as well as aphid defensive behaviors, such as walking, kicking, and jerking. Therefore, the higher vulnerability of kdr-resistant M. persicae could not be capitalized by A. colemani parasitoids under a high concentration of λ-cyhalothrin. Similarly, the parasitism rate, survival of progeny, productivity, sex ratio (proportion of females), longevity, and adult body mass were reduced, and the development time increased with a higher Mp-RR LC20. Our results suggest that A. colemani could efficiently control kdr-resistant and susceptible M. persicae only at lower λ-cyhalothrin concentrations.