Establishment of a Colony of Phlebotomus argentipes under Laboratory Conditions and Morphometric Variation between Wild-Caught and Laboratory-Reared Populations

The field-based studies on sand flies are not adequate to uncover information required for the control of the leishmaniasis through reduction of vector populations. Therefore, establishment and maintenance of laboratory colonies of sand flies is an essential step in leishmaniasis research. In the current study, a colony of P. argentipes was established from wild-caught sand flies following standard procedures from the published literature. Morphological measurements of laboratory-reared and wild-caught individual sand flies were compared to assess the difference between two groups. The colony was successfully established under confined laboratory conditions. The comparison of morphometric parameters revealed that the laboratory-reared sand flies are significantly larger than those caught from wild, suggesting a possibility of increased fitness of sand flies under favorable environmental conditions which may cause higher prevalence in the disease. The current study reports the first successful attempt in colonizing sand flies under laboratory conditions. However, the colony data suggest that the conditions extracted from the published literature need to be optimized to suit local settings in order to achieve maximum population sizes within the available amount of resources.

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False-Positive Titers of Thyroid Autoantibodies in Patients Undergoing Hemodialysis?

Clinical Chemistry ◽

10.1093/clinchem/37.12.2153 ◽

1991 ◽

Vol 37 (12) ◽

pp. 2153-2154 ◽

Cited By ~ 4

Author(s):

Ljerka Lukinac ◽

Zvonko Kusic ◽

Petar Kes

Keyword(s):

Renal Failure ◽

Chronic Renal Failure ◽

False Positive ◽

Serum Samples ◽

Standard Procedures ◽

Before And After ◽

Thyroid Function Testing ◽

Total Triiodothyronine ◽

The Difference ◽

Function Testing

Abstract Concentrations of thyroid-related hormones in serum of patients with chronic renal failure are known to be abnormal (1, 2). In our study on thyroid-function testing of patients undergoing hemodialysis, we determined, in addition to concentrations of free and total triiodothyronine, free and total thyroxin, “reverse” triiodothyronine, and thyroxin-binding globulin, the titers of thyroglobulin and microsomal autoantibodies (TGA and TMA, respectively). The study was provoked by the appearance of an uncommon agglutination pattern in the control wells of some samples from patients with chronic renal failure during the standard procedures of detecting TGA and TMA with hemagglutination methods (Thymune-T and Thymune-M assays from Welcome, London, U.K.). For these samples we were not certain whether positive titers for TGA and (or) TMA represented false-positive or true-positive values. Therefore, we assayed the absorbed serum samples and samples after addition of excess nonspecific immunoglobulin. Furthermore, we wanted to determine the difference in TGA and TMA titers of serum samples before and after hemodialysis.

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Rheology of Polymethylmethacrylate-Collagen Gel Filler: Physiochemical Properties and Clinical Applications

Aesthetic Surgery Journal ◽

10.1093/asj/sjaa314 ◽

2020 ◽

Author(s):

Z Paul Lorenc ◽

Brian Pilcher ◽

Tina McArthur ◽

Nimitt Patel

Keyword(s):

Collagen Gel ◽

Complex Viscosity ◽

Clinical Applications ◽

Published Data ◽

Physiochemical Properties ◽

Standard Procedures ◽

Clinical Considerations ◽

Selection For ◽

The Difference ◽

The Temple

Abstract Background Soft tissue fillers are comprised of a range of materials with differing physiochemical and rheological (ie, flow) properties. These properties can inform treatment selection for specific anatomical areas, planes of injection, and clinical applications. Objective To characterize rheological properties of polymethylmethacrylate (PMMA)-collagen gel for comparison with other available fillers. Methods Commercially available PMMA-collagen gel, hyaluronic acid (HA), and calcium hydroxylapatite (CaHA) fillers were obtained from their respective manufacturers. Measures of complex viscosity (η*) and elastic modulus (G′) for each filler were collected at 0.7 Hz in triplicate using standard procedures on a rotational rheometer fitted with a 40-mm steel plate at 25°C on a Peltier plate (500-μm gap). Results The measured η* and G′ values for HA and CaHA fillers were in agreement with previously published data. The difference in η* between CaHA (358.9 Pa-s, SD=21.56) and PMMA-collagen gel (656.41 Pa-s, SD=68.03) was statistically significant (P<0.0001), as was the difference between the G′ of CaHA (1424.8 Pa, SD=83.3) and the G′ of PMMA-collagen gel (2815.27 Pa, SD=304.07; P<0.0001). Conclusions PMMA-collagen gel exhibited the highest η* and G′ of all tested fillers. These properties likely underpin an increased capacity for lifting and support in areas where long-lasting revolumization is appropriate. In practice, PMMA-collagen gel is well suited for treatment of acne scars, as well as injection into the supraperiosteal plane in the temple, chin, mandible, and piriform using a retrograde linear threading technique. Additional clinical considerations are discussed.

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The Influence of Environmental Features on the Morphometric Variation in Mauritia flexuosa L.f. Fruits and Seeds

Plants ◽

10.3390/plants9101304 ◽

2020 ◽

Vol 9 (10) ◽

pp. 1304

Author(s):

Nilo L. Sander ◽

Carolina J. da Silva ◽

Aline V. M. Duarte ◽

Bruno W. Zago ◽

Carla Galbiati ◽

...

Keyword(s):

Single Species ◽

Fruit Weight ◽

Group Method ◽

Phenotypic Traits ◽

Sequential Method ◽

Morphometric Variation ◽

Pair Group ◽

Mauritia Flexuosa ◽

The Difference ◽

Fresh Pulp

The environmental heterogeneity may reflect the different morphological and phenotypic traits of individuals belonging to a single species. We used 14 morphological traits of Mauritia flexuosa L.f. to understanding the relation between environment and phenotypic traits. Twenty-five fruits were collected from each of the 10 individuals sampled in each study site: Chapada dos Guimarães (CG), Vila Bela da Santíssima Trindade (VB), and Alta Floresta (AF). We analyzed the genetic divergence, using the standardized Euclidean distance, the sequential method of Tocher, unweighted pair group method with arithmetic mean (UPGMA), and the projection of the distances onto 2D plane, and calculated the relative importance of the traits evaluated. The analysis showed the partition of individuals into three main groups: Two groups comprising the majority of individuals. Fresh fruit weight, pulp rate, fresh pulp weight, and moisture rate were the traits that most helped explaining the difference between materials. The results shown in the current study evidenced the influence of these three different environments on the biometric traits of M. flexuosa. Such influence has led to the formation of Alta Floresta and Vila Bela da Santíssima Trindade individuals in different groups, whereas the Chapada dos Guimarães individuals were able to permeate the two other groups, although they showed stronger tendency to group with individuals from Vila Bela da Santíssima Trindade.

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Glossina (Diptera: Glossinidae) population growth rates

Bulletin of Entomological Research ◽

10.1017/s0007485300008531 ◽

1981 ◽

Vol 71 (3) ◽

pp. 519-531 ◽

Cited By ~ 11

Author(s):

L. Ryan

Keyword(s):

Population Growth ◽

Age Structure ◽

Growth Rates ◽

Optimal Timing ◽

Population Growth Rates ◽

Laboratory Colonies ◽

The Mean ◽

The Difference ◽

Reproductive Rates ◽

Population Equilibrium

AbstractDifferences in population growth rates, r, and net reproductive rates, R0, are shown between Glossina palpalis gambiensis Vanderplank, G. palpalis palpalis (R.-D.), G. morsitans morsitans Westw., G. morsitans centralis Machado, G. pallidipes Aust. and G. fuscipes fuscipes Newst. from field-collected data and laboratory colonies. The relationships of these population parameters with temperature are shown as well as the temperature-dependence of T, the cohort generation time. Two rapid methods for estimating r from R0 knowing the mean temperature, and a more accurate rapid method of calculating r direct from the capacity for increase, re, were developed from these data. The stable age-structure, C, calculated from these data was used to show that the laboratory-derived age-specific fecundity, mx, is 22% higher than in the field. The difference is probably due to natural abortion in the field and the better nutritional status of laboratory-reared flies. Deviation from the stable age-structure is shown to be an indication of the sample bias and population equilibrium. The relationships of these parameters to the state of a given population and to optimal timing of control efforts are considered.

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Susceptibility of field-collected Phlebotomus argentipes (Diptera: Psychodidae) sand flies from Bangladesh and Nepal to different insecticides

Parasites & Vectors ◽

10.1186/s13071-018-2913-6 ◽

2018 ◽

Vol 11 (1) ◽

Cited By ~ 4

Author(s):

Rajib Chowdhury ◽

Murari Lal Das ◽

Vashkar Chowdhury ◽

Lalita Roy ◽

Shyla Faria ◽

...

Keyword(s):

Sand Flies ◽

Phlebotomus Argentipes

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Global Stability of Multigroup SIRS Epidemic Model with Varying Population Sizes and Stochastic Perturbation around Equilibrium

Abstract and Applied Analysis ◽

10.1155/2014/154725 ◽

2014 ◽

Vol 2014 ◽

pp. 1-14 ◽

Cited By ~ 1

Author(s):

Xiaoming Fan

Keyword(s):

Deterministic Model ◽

Reproduction Number ◽

Stochastic Perturbation ◽

Endemic Equilibrium ◽

Random Perturbations ◽

Sirs Epidemic Model ◽

Population Sizes ◽

Time Average ◽

The Difference ◽

Varying Population

We discuss multigroup SIRS (susceptible, infectious, and recovered) epidemic models with random perturbations. We carry out a detailed analysis on the asymptotic behavior of the stochastic model; when reproduction numberℛ0>1, we deduce the globally asymptotic stability of the endemic equilibrium by measuring the difference between the solution and the endemic equilibrium of the deterministic model in time average. Numerical methods are employed to illustrate the dynamic behavior of the model and simulate the system of equations developed. The effect of the rate of immunity loss on susceptible and recovered individuals is also analyzed in the deterministic model.

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Understanding Behavioural Temperament of Phlebotomus argentipes Under the Influence of DDT-IRS Versus SP-IRS for Scoping New Approaches for Maximum Control Over the VL-Vector Population in Bihar

International Journal of TROPICAL DISEASE & Health ◽

10.9734/ijtdh/2019/v40i130217 ◽

2019 ◽

pp. 1-11

Author(s):

Vijay Kumar ◽

Aarti Rama ◽

Rakesh Mandal ◽

Pradeep Das

Keyword(s):

Vector Control ◽

Light Trap ◽

Maintenance Phase ◽

Chemical Constituent ◽

Sand Fly ◽

Successful Implementation ◽

Sand Flies ◽

Phlebotomus Argentipes ◽

Grass Root Level ◽

The Impact

Background: After the decades of Dichlorodiphenyltrichloroethane (DDT) use, Phlebotomus argentipes reportedly developed resistance against it affecting every aspect of vector control at grass-root level. Although DDT based Indoor Residual Spray (IRS) has been replaced with Alphacypermethrine-a Synthetic Pyrethroid (SP) based insecticide, since 2016 but its successful implementation at the Visceral Leishmaniasis (VL) endemic regime of Bihar doesn’t cause much effect upon VL vector density. Furthermore, the outcomes of existing operational research works, it had been observed that VL vectors are continuously changing its behavior under the pressure of insecticides. Methods: For validating the hypothesis, present study has been carried out at Vaishali and Patna being highly and semi-endemic sites respectively for quantifying the oriental behavior among VL vectors persuaded by the IRS and enforce them to remain alive and get trapped in light trap even after changed chemical composition of IRS i.e., SP-IRS from routine DDT-IRS. Results: Following results, a significant reduction in sand fly density (i.e., 33.09% and 29.16%) was observed for outdoor and indoor caught sand flies, collected with light trap and aspirator respectively. Significant higher no. of sand fly collection in terms of per light traps per night was recorded from the outdoor sites than those from indoor habitat for each village of Vaishali and Saran district of Bihar. Higher no. of male sand flies than to that of female ones were collected from outdoor sites and only unfed female sand flies (i.e., 100%) were caught following SP-IRS from each study villages of Vaishali and Saran districts of Bihar. Conclusions: The results of higher no. of sand flies collection from the outdoor sites as compared with the indoor habitat validate the hypothesis of gradual shifting of habitat of VL vectors from endophilic to exophilic which is undoubtedly followed due to the fact of developed resistance among them against chemical constituent of IRS. Results provide very useful information about the sand fly dynamics under the impact of IRS and accordingly, advocates the combined approach of IRS along with insecticidal fogging together at a same time that could be an effective dividend for maximum VL vector control along for negotiating VL cases at par for longer duration during the maintenance phase at the VL foci.

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Evidence of cryptic incidence in childhood diseases

10.1101/079194 ◽

2016 ◽

Author(s):

Christian E. Gunning ◽

Matthew J. Ferrari ◽

Erik Erhardt ◽

Helen J. Wearing

Keyword(s):

Case Reports ◽

Disease Incidence ◽

Marginal Probability ◽

Childhood Diseases ◽

Small Cities ◽

Scaling Relationship ◽

Population Sizes ◽

The Difference ◽

Infectious Disease Dynamics ◽

Poor Reporting

AbstractPersistence and extinction are key processes in infectious disease dynamics that, due to incomplete reporting, are seldom directly observable. For fully-immunizing diseases, reporting probabilities can be readily estimated from demographic records and case reports. Yet reporting probabilities are not sufficient to unambiguously reconstruct disease incidence from case reports. Here, we focus on disease presence (i.e., marginal probability of non-zero incidence), which provides an upper bound on the marginal probability of disease extinction. We examine measles and pertussis in pre-vaccine era U.S. cities, and describe a conserved scaling relationship between population size, reporting probability, and observed presence (i.e., non-zero case reports). We use this relationship to estimate disease presence given perfect reporting, and define cryptic presence as the difference between estimated and observed presence. We estimate that, in early 20th century U.S. cities, pertussis presence was higher than measles presence across a range of population sizes, and that cryptic presence was common in small cities with imperfect reporting. While the methods employed here are specific to fully-immunizing diseases, our results suggest that cryptic incidence deserves careful attention, particularly in diseases with low case counts, poor reporting, and longer infectious periods.

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