Leishmania in phlebotomid sandflies. II. The insusceptibility of sandfly larvae to Leishmania

1975 ◽  
Vol 188 (1091) ◽  
pp. 229-231 ◽  
Keyword(s):  
Fourth Instar ◽  
Related Genus ◽  
Leishmania Mexicana ◽  
Invertebrate Host ◽  
Infected Female

The susceptibility of fourth instar larvae of Lutzomyia flaviscutellata to Leishmania mexicana amazonensis was investigated by feeding them infected female sandflies or cultured promastigotes. Neither larvae nor adult flies reared from the larvae became infected. It is suggested that during evolution Leishmania has lost the ability, retained by the related genus Leptomonas , to be transmitted in nature from one invertebrate host to another.

scholarly journals Cryptic Paraflagellar Rod in Endosymbiont-Containing Kinetoplastid Protozoa

2005 ◽  
Vol 4 (3) ◽  
pp. 516-525 ◽  
Author(s):  
Catarina Gadelha ◽  
Bill Wickstead ◽  
Wanderley de Souza ◽  
Keith Gull ◽  
Narcisa Cunha-e-Silva
Keyword(s):  
Null Mutation ◽  
Biological Processes ◽  
Leishmania Mexicana ◽  
Invertebrate Host ◽  
Diverse Range ◽  
Apparent Lack ◽  
As Species ◽  
Cilia And Flagella ◽  
Genome Information ◽  
Metabolic Regulators

ABSTRACT Cilia and flagella are central to many biological processes in a diverse range of organisms. The kinetoplastid protozoa are very appealing models for the study of flagellar function, particularly in the light of the availability of extensive trypanosomatid genome information. In addition to the highly conserved 9 + 2 axoneme, the kinetoplastid flagellum contains a characteristic paraflagellar rod structure (PFR). The PFR is necessary for full motility and provides support for metabolic regulators that may influence flagellar beating. However, there is an intriguing puzzle: one clade of endosymbiont-containing kinetoplastids apparently lack a PFR yet are as motile as species that possess a PFR and are able to attach to the invertebrate host epithelia. We investigated how these organisms are able to locomote despite the apparent lack of PFR. Here we have identified a PFR1 gene in the endosymbiont-bearing trypanosome Crithidia deanei. This gene is expressed in C. deanei and is able to partially complement a pfr1 null mutation in Leishmania mexicana cells, demonstrating that the encoded protein is functional. Careful reexamination of C. deanei flagellar ultrastructure revealed a greatly reduced PFR missed by many previous analyses. This affirms the PFR as a canonical organelle of kinetoplastids. Moreover, although PFR proteins have been conserved in evolution, primary sequence differences contribute to particular PFR morphotypes characteristic of different kinetoplastid species.

Risk Factors in Diabetes and Pregnant Women with Urinary Tract Infections Compared to Younger Aged Female.

2018 ◽  
Vol 1 (3) ◽  
pp. 26-38
Author(s):  
Abdulghani Mohamed Alsamarai ◽  
Shler Ali Khorshed
Keyword(s):  
Risk Factors ◽  
Urinary Tract Infection ◽  
Urinary Tract ◽  
Tract Infection ◽  
Pregnant Women ◽  
Female Student ◽  
Mean Value ◽  
Infected Female ◽  
Significant Difference ◽  
Tract Infections

Background: Urinary tract infection is common with health impact in women and characterised by failure to treatment and recurrent episodes. Aim: This study was conducted to determine the risk factors for the development of urinary tract infection in diabetic and pregnant women in comparison to student female. Materials and methods: A prospective cross-sectional study conducted during the period from 1st of June 2015 to the end of January 2016. The population included in the study are 563 women, of them 425 were outpatients, and 138 were inpatients. Their age range between 18 and 80 years, with a mean age of 33.59±15.29 years. Urine samples collected and cultured on blood agar and MacConkey agar by spread plate technique. Bacterial colonies with different morphology were selected, purified and identified according to their biochemical characteristics using conventional standard methods. Results: In diabetic women, there were no significant difference in mean age and BMI values between culture positive and culture negative groups. However, pus cell mean scale was significantly higher [P=0.000] in women with urinary tract infection [1.76±1.25] than in those with negative culture [0.69±1.00]. In pregnant women, BMI mean value was significantly [P=0.013] lower in pregnant women with UTI [26.14] as compared to those without infection [26.99]. Pus cell scale mean value was significantly [P=0.000] higher in pregnant women with UTI [1.55] than women with negative UTI [0.85]. While there was no significant difference in mean age between UTI positive and negative pregnant women. In female student, there was a significant difference between UTI infected and non-infected in mean age [P=0.041] and pus cell scale [P=0.000]. However, BMI was not significantly different between infected and non-infected female student. Other risk factors association are variables in the 3 groups when analysed using X2, while AUC and OR show different trends of association between risk factors and UTI. Conclusion: BMI, pus cell scale, child number, delivery method, operation history and hospital setting were significantly associated with culture positivity in the 3 studied groups as determined by AUC. While OR confirmed association with pus sale scale in the 3 groups.

Design of Inhibitors for Glyceraldehyde-3-phosphate Dehydrogenase (GAPDH) Enzyme of Leishmania mexicana

2020 ◽  
Vol 16 (6) ◽  
pp. 784-795
Author(s):  
Krisnna M.A. Alves ◽  
Fábio José Bonfim Cardoso ◽  
Kathia M. Honorio ◽  
Fábio A. de Molfetta
Keyword(s):  
Molecular Dynamics ◽  
Molecular Dynamics Simulations ◽  
Binding Site ◽  
Point Of View ◽  
New Drugs ◽  
Leishmania Mexicana ◽  
Receptor Complexes ◽  
Starting Point ◽  
Dynamics Simulations ◽  
Selection Of

Background:: Leishmaniosis is a neglected tropical disease and glyceraldehyde 3- phosphate dehydrogenase (GAPDH) is a key enzyme in the design of new drugs to fight this disease. Objective:: The present study aimed to evaluate potential inhibitors of GAPDH enzyme found in Leishmania mexicana (L. mexicana). Methods: A search for novel antileishmanial molecules was carried out based on similarities from the pharmacophoric point of view related to the binding site of the crystallographic enzyme using the ZINCPharmer server. The molecules selected in this screening were subjected to molecular docking and molecular dynamics simulations. Results:: Consensual analysis of the docking energy values was performed, resulting in the selection of ten compounds. These ligand-receptor complexes were visually inspected in order to analyze the main interactions and subjected to toxicophoric evaluation, culminating in the selection of three compounds, which were subsequently submitted to molecular dynamics simulations. The docking results showed that the selected compounds interacted with GAPDH from L. mexicana, especially by hydrogen bonds with Cys166, Arg249, His194, Thr167, and Thr226. From the results obtained from molecular dynamics, it was observed that one of the loop regions, corresponding to the residues 195-222, can be related to the fitting of the substrate at the binding site, assisting in the positioning and the molecular recognition via residues responsible for the catalytic activity. Conclusion:: he use of molecular modeling techniques enabled the identification of promising compounds as inhibitors of the GAPDH enzyme from L. mexicana, and the results obtained here can serve as a starting point to design new and more effective compounds than those currently available.

scholarly journals Inhibition of glycosylphosphatidylinositol biosynthesis in Leishmania mexicana by mannosamine

1993 ◽  
Vol 268 (13) ◽  
pp. 9570-9577
Author(s):  
M.C. Field ◽  
E. Medina-Acosta ◽  
G.A. Cross
Keyword(s):  
Leishmania Mexicana

scholarly journals Deep Malaria Parasite Detection in Thin Blood Smear Microscopic Images

2021 ◽  
Vol 11 (5) ◽  
pp. 2284
Author(s):  
Asma Maqsood ◽  
Muhammad Shahid Farid ◽  
Muhammad Hassan Khan ◽  
Marcin Grzegorzek
Keyword(s):  
Neural Networks ◽  
Deep Learning ◽  
Red Blood Cells ◽  
Convolutional Neural Networks ◽  
Blood Cells ◽  
Superior Performance ◽  
Learning Models ◽  
Infected Female ◽  
The World ◽  
Augmentation Techniques

Malaria is a disease activated by a type of microscopic parasite transmitted from infected female mosquito bites to humans. Malaria is a fatal disease that is endemic in many regions of the world. Quick diagnosis of this disease will be very valuable for patients, as traditional methods require tedious work for its detection. Recently, some automated methods have been proposed that exploit hand-crafted feature extraction techniques however, their accuracies are not reliable. Deep learning approaches modernize the world with their superior performance. Convolutional Neural Networks (CNN) are vastly scalable for image classification tasks that extract features through hidden layers of the model without any handcrafting. The detection of malaria-infected red blood cells from segmented microscopic blood images using convolutional neural networks can assist in quick diagnosis, and this will be useful for regions with fewer healthcare experts. The contributions of this paper are two-fold. First, we evaluate the performance of different existing deep learning models for efficient malaria detection. Second, we propose a customized CNN model that outperforms all observed deep learning models. It exploits the bilateral filtering and image augmentation techniques for highlighting features of red blood cells before training the model. Due to image augmentation techniques, the customized CNN model is generalized and avoids over-fitting. All experimental evaluations are performed on the benchmark NIH Malaria Dataset, and the results reveal that the proposed algorithm is 96.82% accurate in detecting malaria from the microscopic blood smears.

Infectivity of entomopathogenic nematodes against the legume pod-borer, Maruca vitrata Fabricius, infesting pigeon pea

2021 ◽  
Vol 95 ◽  
Author(s):  
R. Pervez ◽  
U. Rao
Keyword(s):  
Entomopathogenic Nematodes ◽  
Agricultural Research ◽  
Insect Pest ◽  
Indian Agricultural Research Institute ◽  
Pigeon Pea ◽  
Fourth Instar ◽  
Maruca Vitrata ◽  
Pod Borer ◽  
Legume Pod Borer ◽  
Maximum Penetration

Abstract The legume pod-borer, Maruca vitrata Fabricius (Lepidoptera: Crambidae) (LPB), is an important insect pest of pigeon pea. Chemical pesticides are generally employed to manage this pest, but because of the soil residue issues and other environmental hazards associated with their use, biopesticides are also in demand. Another benign alternative is to use entomopathogenic nematodes (EPNs) to manage this vital pest. In the present study, the infectivity of ten native EPNs was evaluated against LPB by assessing their penetration and production in the LPB. The effectiveness of the promising EPNs against second-, third- and fourth-instar LPB larvae was also studied. Heterorhabditis sp. (Indian Agricultural Research Institute-Entomopathogenic Nematodes Rashid Pervez (IARI-EPN RP) 06) and Oscheius sp. (IARI-EPN RP 08) were found to be most pathogenic to LPB, resulting in about 100% mortality within 72 h, followed by Steinernema sp. (IARI-EPN RP 03 and 09). Oscheius sp. (IARI-EPN RP 04) was found to be the least pathogenic to LPB larva with 67% mortality. Maximum penetration was exhibited by Heterorhabditis sp. (IARI-EPN RP 06) followed by Oscheius sp. (IARI-EPN RP 08), whereas the lowest rate of penetration was exhibited by Oscheius sp. (IARI-EPN RP 01). The highest rate of production was observed with Oscheius sp. (IARI-EPN RP 08), followed by Oscheius sp. (IARI-EPN RP 04 and 10). Among the tested instars of the LPB larvae, second-instar larvae were more susceptible to EPNs, followed by third- and fourth-instar larvae. The results indicate that Heterorhabditis sp. (IARI-EPN RP 06) and Oscheius sp. (IARI-EPN RP 08) have a good potential to the manage LPB.

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