Resistance development characteristics of reared German cockroach (Blattodea: Blattellidae) to chlorpyrifos

AbstractUnderstanding the process of resistance development of German cockroach, Blattella germanica (L.), in detail is necessary to potentially delay the development of insecticides resistance by rotation or discontinuation of insecticides at the right time. In this study, we investigated the resistance development of the reared German cockroach to chlorpyrifos (CPF) for 23 generations from susceptible cockroaches. CPF 50% lethal dose (LD50) and resistance ratio of each generation cockroaches were determined. The CPF LD50 to each generation cockroaches was used as the insecticide selection pressure of this generation by topical application. The resistance development curve was depicted according to the CPF LD50 to all 23 generations of cockroaches. As a result, a highly resistant German cockroach cohort to CPF, which the resistance ratio was 21.63, was obtained after 23 generations’ selection. During the selection, the cockroaches developed low resistance from F1 to F5, moderate resistance from F6 to F12, and high resistance from F13 to F23. There was a rapid resistance increase every 5–7 generations. The resistance growing showed relatively slow from F1 to F11. The fastest growing phase of the resistance was from F12 to F20, in which accounted for more than 80% of the total resistance increase in 23 generations. The development of resistance to CPF tended to slow down from F21 to F23. These findings may provide a basis for the rational use of insecticides, delaying the development of resistance by rotation or discontinuation.

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Resistance status and the rate of resistance development in Musca domestica Linnaeus (Diptera: Muscidae) to permethrin and imidacloprid in Indonesia

Jurnal Entomologi Indonesia ◽

10.5994/jei.18.3.159 ◽

2021 ◽

Vol 18 (3) ◽

pp. 159-169

Author(s):

Sri Yusmalinar ◽

◽

Tjandra Anggraeni ◽

Ramadhani Eka Putra ◽

Ashari Zain ◽

...

Keyword(s):

Musca Domestica ◽

High Resistance ◽

Management Strategies ◽

Repeated Application ◽

Resistance Level ◽

Resistance Development ◽

Development Of Resistance ◽

Pest Infestation ◽

Moderate Resistance ◽

Very High

A previous report has indicated that in many regions of Indonesia, populations of Musca domestica Linnaeus have shown very high resistance to permethrin and low resistance to imidacloprid. In this study, the resistance status to permethrin and imidacloprid was updated using a topical application and feeding bioassay. Six housefly strains originated from six highly populated cities in Indonesia, namely Serang (SRG), Jakarta (JKT), Bandung (BDG), Semarang (SMG), Yogyakarta (JOG), and Surabaya (SBY). A seventh strain (Danish Pest Infestation Laboratory (DPIL)) served as the control. Each strain was tested for resistance to the two insecticides. In addition, the rate of development of resistance to the two insecticides was measured over ten generations. The results indicated that all field strains showed very high resistance to permethrin. The highest resistance level recorded was in the SRG strain (RR50 = 2880), and the lowest was in the JKT strain (RR50 = 520). Repeated application of permethrin over ten generations increased the resistance level by about 2.7–32.73-fold as compared to the level of their respective parental populations. On the other hand, most strains showed low to moderate resistance to imidacloprid, in which the SRG strain had the highest resistance level (RR50 = 15.5) and the SBY strain had the lowest (RR50 = 2.0). Repeated application of imidacloprid over ten generations increased the resistance level by about 3.25–17.41-fold. The findings, which is the second report of housefly resistance in Indonesia since 2016, provide a crucial foundation for developing appropriate housefly integrated pest management strategies in highly populated areas in Indonesia.

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Emergence of ceftazidime/avibactam resistance in KPC-3-producing Klebsiella pneumoniae in vivo

Journal of Antimicrobial Chemotherapy ◽

10.1093/jac/dkz330 ◽

2019 ◽

Vol 74 (11) ◽

pp. 3211-3216 ◽

Cited By ~ 13

Author(s):

Stephan Göttig ◽

Denia Frank ◽

Eleonora Mungo ◽

Anika Nolte ◽

Michael Hogardt ◽

...

Keyword(s):

Combination Therapy ◽

Klebsiella Pneumoniae ◽

Selection Pressure ◽

Galleria Mellonella ◽

Phenotypic Characterization ◽

Infection Model ◽

Development Of Resistance ◽

Time Kill

Abstract Objectives The β-lactam/β-lactamase inhibitor combination ceftazidime/avibactam is active against KPC-producing Enterobacterales. Herein, we present molecular and phenotypic characterization of ceftazidime/avibactam resistance in KPC-3-producing Klebsiella pneumoniae that emerged in vivo and in vitro. Methods Sequence analysis of blaKPC-3 was performed from clinical and in vitro-generated ceftazidime/avibactam-resistant K. pneumoniae isolates. Time–kill kinetics and the Galleria mellonella infection model were applied to evaluate the activity of ceftazidime/avibactam and imipenem alone and in combination. Results The ceftazidime/avibactam-resistant clinical K. pneumoniae isolate revealed the amino acid change D179Y in KPC-3. Sixteen novel mutational changes in KPC-3 among in vitro-selected ceftazidime/avibactam-resistant isolates were described. Time–kill kinetics showed the emergence of a resistant subpopulation under selection pressure with either imipenem or ceftazidime/avibactam. However, combined selection pressure with imipenem plus ceftazidime/avibactam prevented the development of resistance and resulted in bactericidal activity. Concordantly, the G. mellonella infection model revealed that monotherapy with ceftazidime/avibactam is prone to select for resistance in vivo and that combination therapy with imipenem results in significantly better survival. Conclusions Ceftazidime/avibactam is a valuable antibiotic against MDR and carbapenem-resistant Enterobacterales. Based on time–kill kinetics as well as an in vivo infection model we postulate a combination therapy of ceftazidime/avibactam and imipenem as a strategy to prevent the development of ceftazidime/avibactam resistance in KPC-producing Enterobacterales in vivo.

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Development of Resistance in Wild-Type and Hypermutable Pseudomonas aeruginosa Strains Exposed to Clinical Pharmacokinetic Profiles of Meropenem and Ceftazidime Simulated In Vitro

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.00160-07 ◽

2007 ◽

Vol 51 (10) ◽

pp. 3642-3649 ◽

Cited By ~ 19

Author(s):

Beate Henrichfreise ◽

Irith Wiegand ◽

Ingeborg Luhmer-Becker ◽

Bernd Wiedemann

Keyword(s):

Pseudomonas Aeruginosa ◽

Parent Strain ◽

Resistance Mechanisms ◽

In Vitro Models ◽

Wild Type ◽

Resistance Development ◽

Development Of Resistance ◽

Pharmacokinetic Profiles ◽

Mutant Prevention Concentration

ABSTRACT In this study we investigated the interplay of antibiotic pharmacokinetic profiles and the development of mutation-mediated resistance in wild-type and hypermutable Pseudomonas aeruginosa strains. We used in vitro models simulating profiles of the commonly used therapeutic drugs meropenem and ceftazidime, two agents with high levels of antipseudomonal activity said to have different potentials for stimulating resistance development. During ceftazidime treatment of the wild-type strain (PAO1), fully resistant mutants overproducing AmpC were selected rapidly and they completely replaced wild-type cells in the population. During treatment with meropenem, mutants of PAO1 were not selected as rapidly and showed only intermediate resistance due to the loss of OprD. These mutants also replaced the parent strain in the population. During the treatment of the mutator P. aeruginosa strain with meropenem, the slowly selected mutants did not accumulate several resistance mechanisms but only lost OprD and did not completely replace the parent strain in the population. Our results indicate that the commonly used dosing regimens for meropenem and ceftazidime cannot avoid the selection of mutants of wild-type and hypermutable P. aeruginosa strains. For the treatment outcome, including the prevention of resistance development, it would be beneficial for the antibiotic concentration to remain above the mutant prevention concentration for a longer period of time than it does in present regimens.

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Population Structure, Fungicide Resistance Profile, and sdhB Mutation Frequency of Botrytis cinerea from Strawberry and Greenhouse-Grown Tomato in Greece

Plant Disease ◽

10.1094/pdis-04-14-0373-re ◽

2015 ◽

Vol 99 (2) ◽

pp. 240-248 ◽

Cited By ~ 30

Author(s):

Sotirios Konstantinou ◽

Thomas Veloukas ◽

Michaela Leroch ◽

George Menexes ◽

Matthias Hahn ◽

...

Keyword(s):

Botrytis Cinerea ◽

Fungicide Resistance ◽

Sensu Stricto ◽

Sdhb Mutation ◽

Resistance Development ◽

Low Frequencies ◽

Resistance Profile ◽

Development Of Resistance ◽

Crete Island ◽

Of Greece

Botrytis cinerea is a pathogen with high genetic variability that has also shown high risk for fungicide resistance development. In total, 1,169 isolates obtained from strawberry (n = 297) and tomato (n = 872) in five geographic regions of Greece were tested for their sensitivity to several botryticides. A high frequency of isolates with multiple resistance to carbendazim, cyprodinil, pyraclostrobin, and boscalid was found in isolates from strawberry. In the isolates from tomato, the predominant phenotype was that of dual resistance to carbendazim and cyprodinil in the Crete island, of single resistance to carbendazim in the region of Preveza, and of sensitive isolates in the region of Kyparissia. None of the tested isolates was found to be fludioxonil resistant. High frequencies of boscalid-resistant phenotypes were observed in the strawberry isolates, while boscalid-resistance frequency in the tomato isolates was lower. H272R was the predominant sdhB mutation, associated with resistance to boscalid, in all the sampled isolates, while other sdhB mutations were found at low frequencies. B. cinerea group S, identified by the presence of a 21-bp insertion in the transcription factor mrr1 gene, was predominant within the tomato isolates obtained from all three sampled regions, with frequencies ranging from 62 to 75% of the isolates; whereas, within strawberry isolates, B. cinerea was predominant, with frequencies of 75 to 95%. Correlations of isolate genotype and fungicide resistance profile showed that B. cinerea sensu stricto isolates were more prone to the development of resistance to boscalid compared with the Botrytis group S isolates, which may explain the observed predominance of B. cinerea sensu stricto in strawberry fields.

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Evaluation of Resistance Development in Bemisia tabaci Genn. (Homoptera: Aleyrodidae) in Cotton against Different Insecticides

Insects ◽

10.3390/insects12110996 ◽

2021 ◽

Vol 12 (11) ◽

pp. 996

Author(s):

Muhammad Zaryab Khalid ◽

Sohail Ahmed ◽

Ibrahim Al-ashkar ◽

Ayman EL Sabagh ◽

Liyun Liu ◽

...

Keyword(s):

Bemisia Tabaci ◽

The Other ◽

Resistance Development ◽

Susceptible Population ◽

Low Level ◽

Development Of Resistance ◽

Major Pest ◽

Selection For ◽

High Level ◽

Very High

Cotton is a major crop of Pakistan, and Bemisia tabaci (Homoptera: Aleyrodidae) is a major pest of cotton. Due to the unwise and indiscriminate use of insecticides, resistance develops more readily in the whitefly. The present study was conducted to evaluate the resistance development in the whitefly against the different insecticides that are still in use. For this purpose, the whitefly population was selected with five concentrations of each insecticide, for five generations. At G1, compared with the laboratory susceptible population, a very low level of resistance was observed against bifenthrin, cypermethrin, acetamiprid, imidacloprid, thiamethoxam, nitenpyram, chlorfenapyr, and buprofezin with a resistance ratio of 3-fold, 2-fold, 1-fold, 4-fold, 3-fold, 3-fold, 3-fold, and 3-fold, respectively. However, the selection for five generations increased the resistance to a very high level against buprofezin (127-fold), and to a high level against imidacloprid (86-fold) compared with the laboratory susceptible population. While, a moderate level of resistance was observed against cypermethrin (34-fold), thiamethoxam (34-fold), nitenpyram (30-fold), chlorfenapyr (29-fold), and acetamiprid (21-fold). On the other hand, the resistance was low against bifenthrin (18-fold) after selection for five generations. A very low level of resistance against the field population of B. tabaci, at G1, showed that these insecticides are still effective, and thus can be used under the field conditions for the management of B. tabaci. However, the proper rotation of insecticides among different groups can help to reduce the development of resistance against insecticides.

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Comparative Study of the Effect of Solvents on the Efficacy of Neonicotinoid Insecticides Against Malaria Vector Populations Across Africa

10.21203/rs.3.rs-1197098/v1 ◽

2022 ◽

Author(s):

Magellan Tchouakui ◽

Tatiane Assatse ◽

Leon M. J. Mugenzi ◽

Benjamin D. Menze ◽

Daniel Nguiffo-Nguete ◽

...

Keyword(s):

Democratic Republic Of Congo ◽

Natural Populations ◽

Resistance Mechanisms ◽

Lower Mortality ◽

Malaria Vectors ◽

Cross Resistance ◽

Metabolic Resistance ◽

Resistance Development ◽

Development Of Resistance ◽

Bottle Test

Abstract Background New insecticides with a novel mode of action such as neonicotinoids have recently been recommended for public health by WHO. Resistance monitoring of such novel insecticides requires a robust protocol to monitor the development of resistance in natural populations. In this study, we comparatively used three different solvents to assess the susceptibility of malaria vectors to neonicotinoids across Africa.MethodsMosquitoes were collected from May to July 2021 from three agricultural settings in Cameroon (Njombe-Penja, Nkolondom, and Mangoum), the Democratic Republic of Congo (Ndjili-Brasserie), Ghana (Obuasi), and Uganda (Mayuge). Using the CDC bottle test, we compared the effect of three different solvents (ethanol, acetone, MERO) on the efficacy of neonicotinoids against Anopheles gambiae s.l. In addition, TaqMan assays were used to genotype key pyrethroid-resistant markers in An. gambiae and to evaluate potential cross-resistance between pyrethroids and clothianidin.ResultsLower mortality were observed when using absolute ethanol or acetone alone as solvent (11.4- 51.9% mortality in Nkolondom, 31.7- 48.2% in Mangoum, 34.6- 56.1% in Mayµge, 39.4- 45.6% in Obuasi, 83.7- 89.3% in Congo and 71.05- 95.9% in Njombe pendja) compared to acetone + MERO for which 100% mortality were observed for all the populations. Synergist assays (PBO, DEM and DEF) revealed a significant increase of mortality suggesting that metabolic resistance mechanisms are contributing to the reduced susceptibility. A negative association was observed between the L1014F-kdr mutation and clothianidin resistance with a greater frequency of homozygote resistant mosquitoes among the dead than among survivors (OR=0.5; P=0.02). However, the I114T-GSTe2 was in contrast significantly associated with a greater ability to survive clothianidin with a higher frequency of homozygote resistant among survivors than other genotypes (OR=2.10; P=0.013). ConclusionsThis study revealed a contrasted susceptibility pattern depending on the solvents with ethanol/acetone resulting to lower mortality, thus possibly overestimating resistance, whereas the MERO consistently showed a greater efficacy of neonicotinoids but it could prevent to detect early resistance development. Therefore, we recommend monitoring the susceptibility using both acetone alone and acetone+MERO (8-10µg/ml for clothianidin) to capture the accurate resistance profile of the mosquito populations.

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Succinate dehydrogenase inhibitor (SDHI) fungicide resistance prevention strategy

New Zealand Plant Protection ◽

10.30843/nzpp.2011.64.5972 ◽

2011 ◽

Vol 64 ◽

pp. 119-124 ◽

Cited By ~ 4

Author(s):

A.H. McKay ◽

G.C. Hagerty ◽

G.B. Follas ◽

M.S. Moore ◽

M.S. Christie ◽

...

Keyword(s):

New Zealand ◽

High Risk ◽

Succinate Dehydrogenase ◽

Fungicide Resistance ◽

Fungal Pathogens ◽

Resistance Management ◽

Resistance Development ◽

Development Of Resistance ◽

Action Committee ◽

Succinate Dehydrogenase Inhibitor

Succinate dehydrogenase inhibitor (SDHI) fungicides are currently represented in New Zealand by eight active ingredients bixafen boscalid carboxin fluaxapyroxad fluopyram isopyrazam penthiopyrad and sedaxane They are either currently registered or undergoing development in New Zealand for use against a range of ascomycete and basiodiomycete pathogens in crops including cereals ryegrass seed apples pears grapes stonefruit cucurbits and kiwifruit These fungicides are considered to have medium to high risk of resistance development and resistance management is recommended by the Fungicide Resistance Action Committee (FRAC) in Europe Guidelines are presented for use of SDHI fungicides in New Zealand to help avoid or delay the development of resistance in the fungal pathogens that they target

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Individual Laterality in Ghost Crabs (Ocypode saratan) Influences Burrowing Behavior

Symmetry ◽

10.3390/sym13081512 ◽

2021 ◽

Vol 13 (8) ◽

pp. 1512

Author(s):

Reuven Yosef ◽

Michal Daraby ◽

Alexei Semionovikh ◽

Jakub Z. Kosicki

Keyword(s):

Natural Selection ◽

Red Sea ◽

Selection Pressure ◽

Left Handed ◽

Self Defense ◽

Temporal Segregation ◽

Ghost Crabs ◽

Left And Right ◽

Burrowing Behavior ◽

The Right

Behavioral handedness is known to enhance an individual’s handling capabilities. However, the ecological advantages in brachyuran crustaceans remain unclear, despite the Ocypode species having been studied extensively. Thus, in this study, we analyzed the laterality of the endemic Red Sea ghost crab on one beach in Eilat, Israel. We successfully documented the laterality of the large cheliped in 125 crabs; in 60 (48.0%), the right cheliped was larger, and in 64 (51.2%), the left. We also observed temporal segregation between the right- and left-clawed crabs. The right-handed crabs start activity just after sunrise, while left-handed crabs appear ca. 40 min after it. Similarly, temporal segregations were also observed in the evening. The right-clawed crab activity peaked ca. 20 min before sunset, while the left-clawed crabs were active uniformly. Additionally, burrow entrances corresponded to the larger cheliped of the resident individual and is probably a self-defense-related behavior. We conclude that cheliped laterality in O. saratan populations should be considered as a bimodal trait, where left- and right-handedness is not under natural selection pressure.

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Dexmedetomidine elevates the lethal dose threshold of bupivacaine in rats: A dosing study

Human & Experimental Toxicology ◽

10.1177/0960327119889658 ◽

2019 ◽

Vol 39 (3) ◽

pp. 365-373

Author(s):

L Pan ◽

Y Zhang ◽

Y He ◽

Z Chen ◽

S Wang ◽

...

Keyword(s):

Femoral Vein ◽

Lethal Dose ◽

Control Group ◽

Sprague Dawley ◽

Dose Threshold ◽

Sd Rats ◽

Group 12 ◽

Group 3 ◽

The Right ◽

Group 1

Dexmedetomidine (DMED), an alpha-2 adrenoreceptor agonist, has been widely used in regional anesthesia procedures. However, the effect of DMED on local anesthetic cardiotoxicity has not been well delineated. This study consisted of two experiments. In experiment A, 42 Sprague–Dawley (SD) rats were randomly divided into 6 groups ( n = 7), each group was pretreated with DMED 0 μg kg−1 (D0 group), 1 μg kg−1 (D1 group), 3 μg kg−1 (D3 group), 6 μg kg−1 (D6 group), 12 μg kg−1 (D12 group), and 24 μg kg−1 (D24 group), administered through the right femoral vein. In experiment B, 20 SD rats were randomly divided into 4 groups ( n = 5), such as control group, DMED group, yohimbine (YOH) group, and DMED + YOH group. Each subgroup in experiment B was also pretreated similarly as in experiment A. After pretreatment of rats as described above (in experiments A and B), bupivacaine 2.5 mg kg−1 min−1 was infused to induce cardiac arrest. In experiment A, the lethal dose threshold of bupivacaine and plasma bupivacaine concentration in D3 and D6 group were higher than the other groups. In experiment B, there was no interaction between DMED and YOH in lethal dose threshold, arrhythmia time, plasma concentration of bupivacaine, and myocardial content of bupivacaine. DMED doses of 3–6 μg kg−1 elevated the lethal dose threshold of bupivacaine without involvement of the alpha-2 adrenoceptors.

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GC-072, a Novel Therapeutic Candidate for Oral Treatment of Melioidosis and Infections Caused by Select Biothreat Pathogens

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.00834-19 ◽

2019 ◽

Vol 63 (12) ◽

Author(s):

Jeffry D. Shearer ◽

Michelle L. Saylor ◽

Christine M. Butler ◽

Anthony M. Treston ◽

Henry S. Heine ◽

...

Keyword(s):

Acute Phase ◽

Oral Treatment ◽

Lethal Dose ◽

Current Therapy ◽

Content Type ◽

Development Of Resistance ◽

Strong Candidate ◽

Oral Therapeutic ◽

Drug Resistant Strains

ABSTRACT Burkholderia pseudomallei, the etiological agent of melioidosis, is a Gram-negative bacterium with additional concern as a biothreat pathogen. The mortality rate from B. pseudomallei varies depending on the type of infection and extent of available health care; in the case of septicemia, left untreated, it can range from 50% to 90%. Current therapy for melioidosis is biphasic, consisting of parenteral acute-phase treatment for 2 weeks or longer, followed by oral eradication-phase treatment lasting several months. An effective oral therapeutic for outpatient treatment of acute-phase melioidosis is needed. GC-072 is a potent, 4-oxoquinolizine antibiotic with selective inhibitory activity against bacterial topoisomerases. GC-072 has demonstrated in vitro potency against susceptible and drug-resistant strains of B. pseudomallei and is also active against Burkholderia mallei, Bacillus anthracis, Yersinia pestis, and Francisella tularensis. GC-072 is bactericidal both extra- and intracellularly, with rapid killing noted within a few hours and reduced development of resistance compared to that for ceftazidime. GC-072, delivered intragastrically to mimic oral administration, promoted dose-dependent survival in mice using lethal inhalational models of B. pseudomallei infection following exposure to a 24- or 339-LD50 (50% lethal dose) challenge with B. pseudomallei strain 1026b. Overall, GC-072 appears to be a strong candidate for first-line oral treatment of melioidosis.

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