Use of transcriptional age grading technique to determine the chronological age of Sri Lankan Aedes aegypti and Aedes albopictus females

Abstract Background Aedes aegypti and Ae. albopictus are important vectors of human diseases such as dengue, chikungunya, and zika. In Sri Lanka, they have been responsible for transmitting dengue virus. One of the most important parameters influencing the likelihood of arbovirus transmission is the age structure of the mosquito population. However, mosquito age is difficult to measure with accuracy. This study aims to construct multivariate calibration models using the transcriptional abundance of three age-responsive genes: Ae15848 (calcium-binding protein), Ae8505 (structural component of cuticle), and Ae4274 (fizzy cell cycle/cell division cycle 20). Methods The transcriptional age-grading technique was applied to determine the chronological age of Ae. aegypti and Ae. albopictus female mosquito populations from Sri Lanka using the age-responsive genes Ae15848, Ae8505, and Ae4274. Furthermore, Ae. aegypti samples obtained from colonies reared at two temperatures (23 and 27 °C) were used to investigate the influence of temperature on this age-grading technique. Expression levels of these three genes were quantified using reverse transcription qualitative PCR (qRT-PCR), and results were normalized against the housekeeping gene ribosomal gene S17 (RpS17). Results The expression of Ae15848 and Ae8505 decreased with the age of mosquitoes and showed the most significant and consistent change while expression of Ae4274 increased with age. The multivariate calibration models showed > 80% correlation between expression of these age-responsive genes and the age of female mosquitoes at both temperatures. At 27 °C the accuracy of age predictions using the models was 2.19 (± 1.66) days and 2.58 (± 2.06) days for Ae. aegypti and Ae. albopictus females, respectively. The accuracy of the model for Ae. aegypti at 23 °C was 3.42 (± 2.74) days. Conclusions An adult rearing temperature difference of 4 °C (23–27 °C) did not significantly affect the age predictions. The calibration models created during this study could be successfully used to estimate the age of wild Ae. aegypti and Ae. albopictus mosquitoes from Sri Lanka. Graphical Abstract

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Use of Transcriptional Age Grading Technique to Determine the Chronological Age of Sri Lankan Female Dengue Mosquitoes; Aedes Aegypti and Aedes Albopictus

10.21203/rs.3.rs-516665/v1 ◽

2021 ◽

Author(s):

Thilini Chathurika Weeraratne ◽

S.H.P. Parakrama Karunaratne ◽

Lisa S. Reimer ◽

W.A.P. Priyanka de Silva ◽

Charles S. Wondji

Keyword(s):

Sri Lanka ◽

Aedes Aegypti ◽

Calcium Binding ◽

Multivariate Calibration ◽

Housekeeping Gene ◽

Ribosomal Gene ◽

Chronological Age ◽

Calibration Models ◽

Influence Of Temperature On ◽

Age Grading

Abstract Background: Aedes aegypti and Ae. albopictus are important vectors of human diseases such as dengue, chikungunya, and zika. In Sri Lanka, they have been responsible for transmitting the dengue virus. One of the most important parameters that affect the likelihood of arbovirus transmission is the age structure of the mosquito population. However, mosquito age is difficult to measure with accuracy. This study aims to construct Multivariate calibration models using the transcriptional abundance of three age responsive genes: Ae15848 (calcium-binding protein), Ae8505 (structural component of cuticle), and Ae4274 (fizzy cell cycle/cell division cycle 20). Methods: Transcriptional age grading technique was applied to determine the chronological age of Ae. aegypti and Ae. albopictus female mosquito strains from Sri Lanka using the age responsive genes; Ae15848, Ae8505, and Ae4274. Further to investigate the influence of temperature on this age grading technique. Expression levels of these three genes were quantified using reverse transcription qualitative PCR (qRT-PCR) and results were normalized against the housekeeping gene ribosomal gene S17 (RsP17).Results: The expression of Ae15848 and Ae8505 decreased with the age of mosquitoes and, showed the most significant and consistent change while expression of Ae4274 increased with age. The multivariate calibration models showed more than 80% correlation between expression of these age responsive genes and the age of female mosquitoes at both temperatures. At 270C the accuracy of age predictions using the models was 2.19 (±1.66) and 2.58 (±2.06) days for Ae. aegypti and Ae. albopictus females, respectively. The accuracy of the model for Ae. aegypti at 230C was 3.42 (±2.74). Conclusions: An adult rearing temperature difference of 40C (230C to 270C) did not significantly affect the age predictions. The calibration models created during this study could be successfully used to estimate the age of wild Ae. aegypti and Ae. albopictus mosquitoes from Sri Lanka.

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Population genetic dynamics of dengue vectors Aedes aegypti and Aedes albopictus in Sri Lanka: baseline study for designing Wolbachia control method

International Journal of Tropical Insect Science ◽

10.1007/s42690-020-00395-2 ◽

2021 ◽

Author(s):

M. D. Nirmani ◽

K. L. N. S. Perera ◽

G. H. Galhena

Keyword(s):

Sri Lanka ◽

Aedes Aegypti ◽

Aedes Albopictus ◽

Population Genetic ◽

Control Method ◽

Baseline Study ◽

Dengue Vectors

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Strategy for constructing robust multivariate calibration models

Chemometrics and Intelligent Laboratory Systems ◽

10.1016/s0169-7439(99)00028-3 ◽

1999 ◽

Vol 49 (1) ◽

pp. 1-17 ◽

Cited By ~ 76

Author(s):

H. Swierenga ◽

A.P. de Weijer ◽

R.J. van Wijk ◽

L.M.C. Buydens

Keyword(s):

Multivariate Calibration ◽

Calibration Models

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Linear transformations of multivariate calibration models in near infrared spectroscopy: A comparative study

Journal of Near Infrared Spectroscopy ◽

10.1177/0967033517723253 ◽

2017 ◽

Vol 25 (4) ◽

pp. 223-230 ◽

Cited By ~ 1

Author(s):

Joseph Dubrovkin

Keyword(s):

Infrared Spectroscopy ◽

Near Infrared Spectroscopy ◽

Near Infrared ◽

Multivariate Calibration ◽

Cetane Number ◽

Total Protein Content ◽

Prediction Errors ◽

Calibration Data ◽

Linear Transformations ◽

Calibration Models

It was shown that linear transformations are suitable for use in multivariate calibration in near infrared spectroscopy as data compression tools. Partial Least Squares calibration models were built using spectral data transformed by expansion in the series of classical orthogonal polynomials, Fourier and wavelet harmonics. These models allowed effective prediction of the cetane number of diesel fuels, Brix and pol parameters of syrup in sugar production and fat and total protein content in milk. Depending on the compression ratio, prediction errors were no larger than 30% of corresponding errors obtained by the use of the non-transformed models. Although selection of the most suitable transformation depends on the calibration data and on the cross-validation method, in many cases Fourier transform gave satisfactory results.

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Maintaining the predictive abilities of multivariate calibration models by spectral space transformation

Analytica Chimica Acta ◽

10.1016/j.aca.2011.02.014 ◽

2011 ◽

Vol 690 (1) ◽

pp. 64-70 ◽

Cited By ~ 57

Author(s):

Wen Du ◽

Zeng-Ping Chen ◽

Li-Jing Zhong ◽

Shu-Xia Wang ◽

Ru-Qin Yu ◽

...

Keyword(s):

Multivariate Calibration ◽

Spectral Space ◽

Space Transformation ◽

Calibration Models

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Different spectrophotometric and TLC-densitometric methods for determination of olmesartan medoxomil and hydrochlorothiazide and their degradation products

European Journal of Chemistry ◽

10.5155/eurjchem.9.4.400-407.1784 ◽

2018 ◽

Vol 9 (4) ◽

pp. 400-407 ◽

Cited By ~ 3

Author(s):

Selvia Maged Adly ◽

Maha Mohamed Abdelrahman ◽

Nada Sayed Abdelwahab ◽

Nourudin Wageh Ali

Keyword(s):

Multivariate Calibration ◽

Degradation Products ◽

External Validation ◽

Olmesartan Medoxomil ◽

Partial Least Square ◽

Least Square ◽

Pharmaceutical Dosage Form ◽

Calibration Models ◽

Significant Difference

In this work, multivariate calibration models and TLC-densitometric methods have been developed and validated for quantitative determination of olmesartan medoxomil (OLM) and hydrochlorothiazide (HCZ) in presence of their degradation products, olmesartan (OL) and salamide (SAL), respectively. In the first method, multivariate calibration models including principal component regression (PCR) and partial least square (PLS) were applied. The wavelength range 210-343 nm was used and data was auto-scaled and mean centered as pre-processing steps for PCR and PLS models, respectively. These models were tested by application to external validation set with mean percentage recoveries 99.78, 100.01, 100.41 and 100.46% for OLM, HCZ, OL and SAL, respectively, for PLS model and also, 100.22, 100.40, 102.25 and 100.13% for them, respectively, for PCR model. The second method is TLC-densitometry at which the chromatographic separation was carried out using silica gel 60F254 TLC plates and the developing system consisted of a mixture of ethyl acetate:chloroform:methanol: formic acid:tri-ethylamine (60:40:4:4:1, by volume) with UV-scanning at 254 nm. The developed methods were successfully applied for determination of OLM and HCZ in their pharmaceutical dosage form. Also, statistical comparison was made between the developed methods and the reported method using student’s-t test and F-test and results showed that there was no significant difference between them concerning both accuracy and precision.

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