scholarly journals American tripanosomiasis: a study on the prevalence of Trypanosoma cruzi and Trypanosoma cruzi-like organisms in wild rodents in San Luis province, Argentina

2010 ◽  
Vol 43 (3) ◽  
pp. 249-253 ◽  
Author(s):  
Ana María Brigada ◽  
Roberto Doña ◽  
Enrique Caviedes-Vidal ◽  
Edgardo Moretti ◽  
Beatriz Basso
Keyword(s):  
Trypanosoma Cruzi ◽  
Natural Habitat ◽  
Laboratory Animals ◽  
Wild Rodents ◽  
Transmission Cycle ◽  
San Luis ◽  
Calomys Musculinus ◽  
Northern Regions ◽  
Set Up

INTRODUCTION: Chagas disease is caused by Trypanosoma cruzi. Wild and perianthropic mammals maintain the infection/transmission cycle, both in their natural habitat and in the peridomestic area. The aim of this paper was to present the results from a study on wild rodents in the central and northern regions of San Luis province, Argentina, in order to evaluate the prevalence of this infection. METHODS: Sherman traps were set up in capture areas located between latitudes 32º and 33º S, and longitudes 65º and 66º W. The captured rodents were taxonomically identified and hemoflagellates were isolated. Morphological, biometric and molecular studies and in vitro cultures were performed. Infection of laboratory animals and histological examination of the cardiac muscle and inoculation area were also carried out. Parasites were detected in circulating blood in Calomys musculinus, Graomys griseoflavus, Phyllotis darwini and Akodon molinae. The parasites were identified using biological criteria. Molecular PCR studies were performed on some isolates, which confirmed the characterization of these hemoflagellates as Trypanosoma cruzi. RESULTS AND CONCLUSIONS: Forty-four percent of the 25 isolates were identified as Trypanosoma cruzi, and the remaining 56% as Trypanosoma cruzi-like. These findings provide evidence that wild rats infected with Trypanosoma cruzi and Trypanosoma cruzi-like organisms are important in areas of low endemicity.

Immunocontraception in rodents: a review of the development of a sperm-based immunocontraceptive vaccine for the grey squirrel (Sciurus carolinensis)

1997 ◽  
Vol 9 (1) ◽  
pp. 125 ◽  
Author(s):  
H. D. M. Moore ◽  
N. M. Jenkins ◽  
C. Wong
Keyword(s):  
Oral Immunization ◽  
Laboratory Animals ◽  
Sciurus Carolinensis ◽  
Wild Rodents ◽  
Grey Squirrel ◽  
Vitro Fertilization ◽  
Contraceptive Vaccine ◽  
Population Turnover ◽  
Contraceptive Vaccines

The strategy for developing contraceptive vaccines for wild rodents will depend on the species. In rats and mice, high all-year birth rates, high levels of dispersal and promiscous mating systems suggest that, if immunocontraception was used alone, >90% of the population would have to sterilized to achieve the desired control. In Britain, the grey squirrel (Sciurus carolinensis) may be a better candidate to investigate the feasibility of a contraceptive vaccine in rodents. This introduced species is a seasonal breeder with a much lower population turnover than rats or mice. As well as causing damage to woodland, it has ousted the native red squirrel (S. valgaris) from most of the UK. A humane and selective method for the control of grey squirrels is therefore highly desirable Numerous sperm-specific antigens have been identified on rodent spermatozoa. Monoclonal antibodies to particular components block sperm–egg interactions in laboratory animals and cross-react with grey squirrel spermatozoa. In vitro fertilization assays indicate that squirrel sperm–egg binding may be inhibited also. Currently, a cDNA library obtained from grey squirrel testis is being screened to identify genes encoding specific sperm antigens involved in fertilization. Methods of enhancing immunogenicity after oral immunization using microparticle carriers and immune-stimulating complexes are currently under investigation.

scholarly journals Successful capacitation and homologous fertilization in vitro in Calomys musculinus and Calomys laucha (Rodentia - sigmodontinae)

Reproduction ◽  
2000 ◽  
pp. 41-47 ◽  
Author(s):  
A Lasserre ◽  
E Cebral ◽  
AD Vitullo
Keyword(s):  
In Vitro Fertilization ◽  
Sperm Motility ◽  
Acrosome Reaction ◽  
Polar Body ◽  
Laboratory Animals ◽  
Fertilization In Vitro ◽  
Vitro Fertilization ◽  
Calomys Musculinus ◽  
Calomys Laucha

Small South American rodents of the genus Calomys have been used extensively for virology and ecological research. Previous studies have demonstrated that Calomys musculinus and Calomys laucha have a relatively short oestrous cycle and that superovulation and parthenogenetic activation can be induced. The purpose of this study was to determine the requirements for in vitro manipulation of the male gamete and in vitro fertilization. Two culture media and different concentrations of spermatozoa were tested for their ability to support sperm motility, hyperactivation and the acrosome reaction. The ability of capacitated Calomys spermatozoa to penetrate zona-free hamster eggs was also evaluated. In vitro fertilization was assessed by examining attachment and binding to the zona pellucida, second polar body extrusion, pronucleus formation and the fertilizing sperm tail. The results of the study showed that: (i) Tyrode's albumin lactate pyruvate (TALP) medium was more effective than T6 medium for maintaining sperm motility in vitro; (ii) hyperactivation was achieved with TALP but not with T6; (iii) the acrosome reaction was easily distinguished by light microscopy and depends on time and sperm concentration; (iv) capacitated spermatozoa are able to penetrate zona-free hamster eggs; and (v) superovulated oocytes can be fertilized in vitro. This is the first report of capacitation and in vitro fertilization for Calomys sp. These results provide opportunities to use C. musculinus and C. laucha as new laboratory animals for research into reproductive biology.

scholarly journals RESEARCH OF ANTIOXIDANT PROPERTIES OF EXTRACTS OF THE PLANTS AND THE CALLUS BIOMASS

2017 ◽  
Vol 10 (7) ◽  
pp. 182 ◽  
Author(s):  
Roksolana Konechna ◽  
Оksana Khropot ◽  
Romana Petrina ◽  
Maria Kurka ◽  
Zoriana Gubriy ◽  
...  
Keyword(s):  
Natural Habitat ◽  
Antioxidant Properties ◽  
Biologically Active Substances ◽  
Biologically Active ◽  
Plant Materials ◽  
Biomass Extract ◽  
Set Up ◽  
Definition Of ◽  
Active Substances

Objective: This study was undertaken to research of antioxidant properties of extracts of the plants and the callus biomass.Methods: The implementation of the method of cultivating the cells, tissues, and organisms in vitro for the reception of biological material of Carlina аcaulis L. (Asteraceae) is a timely issue for the medical and pharmaceutic industry, as the domestication in vitro creates the opportunity for the year-round production of the plant material as the source of biologically active substances. The seeds and plant materials (roots) of C. acaulis L. collected from natural habitat - meadows mountains Klyva Tarnychkovain Ukraine in the Carpathians. The influence of phytohormones on growth processes of plant cells is researched; the optimal conditions for the cultivation of C. acaulis L. are defined and chosen. Biomass extract is obtained and researched for the presence of biologically active substances and conducted definition of oxygen radical absorbance capacity (ORAC) of extracts of medical herbs and callus biomass of C. acaulis L.Results: C. аcaulis L. was cultivated in vitro. There was set up a scheme of sterilization of seeds with the biggest outcome of aseptic explants. There took place the investigation of the qualitative content of the extracts of callus biomass of C. acaulis L. and the detection of flavonoids and tannins. Conducted definition of ORAC of extracts of medical herbs and callus biomass of C. acaulis L. Conclusion: The obtained data showed that the investigated extracts of callus biomass and biomass of the medical herb C. acaulis L. having antioxidant activity, which makes it possible to continue research in this direction.

scholarly journals Elucidating the 3D Structure of a Surface Membrane Antigen from Trypanosoma cruzi as a Serodiagnostic Biomarker of Chagas Disease

Vaccines ◽  
2022 ◽  
Vol 10 (1) ◽  
pp. 71
Author(s):  
Flavio Di Pisa ◽  
Stefano De Benedetti ◽  
Enrico Mario Alessandro Fassi ◽  
Mauro Bombaci ◽  
Renata Grifantini ◽  
...  
Keyword(s):  
Trypanosoma Cruzi ◽  
Chagas Disease ◽  
Polyclonal Antibodies ◽  
Surface Membrane ◽  
3D Structure ◽  
Protozoan Parasite ◽  
Early Screening ◽  
Infected People ◽  
Set Up

Chagas disease (CD) is a vector-borne parasitosis, caused by the protozoan parasite Trypanosoma cruzi, that affects millions of people worldwide. Although endemic in South America, CD is emerging throughout the world due to climate change and increased immigratory flux of infected people to non-endemic regions. Containing of the diffusion of CD is challenged by the asymptomatic nature of the disease in early infection stages and by the lack of a rapid and effective diagnostic test. With the aim of designing new serodiagnostic molecules to be implemented in a microarray-based diagnostic set-up for early screening of CD, herein, we report the recombinant production of the extracellular domain of a surface membrane antigen from T. cruzi (TcSMP) and confirm its ability to detect plasma antibodies from infected patients. Moreover, we describe its high-resolution (1.62 Å) crystal structure, to which in silico epitope predictions were applied in order to locate the most immunoreactive regions of TcSMP in order to guide the design of epitopes that may be used as an alternative to the full-length antigen for CD diagnosis. Two putative, linear epitopes, belonging to the same immunogenic region, were synthesized as free peptides, and their immunological properties were tested in vitro. Although both peptides were shown to adopt a structural conformation that allowed their recognition by polyclonal antibodies raised against the recombinant protein, they were not serodiagnostic for T. cruzi infections. Nevertheless, they represent good starting points for further iterative structure-based (re)design cycles.

Unusual dimeric flavonoids from Arrabidaea brachypoda with very significant in vitro and in vivo anti-Trypanosoma cruzi activity

Planta Medica ◽  
2014 ◽  
Vol 80 (16) ◽  
Author(s):  
C Quitino-da-Rocha ◽  
E Ferreira-Queiroz ◽  
C Santana-Meira ◽  
DR Magalhães-Moreira ◽  
M Botelho-Pereira-Soares ◽  
...  
Keyword(s):  
Trypanosoma Cruzi

A Heparin-coated Circuit Maintains Platelet Aggregability in Response to Shear Stress in an In Vitro Model of Cardiopulmonary Bypass

1998 ◽  
Vol 80 (09) ◽  
pp. 437-442 ◽  
Author(s):  
I. Hioki ◽  
K. Onoda ◽  
T. Shimono ◽  
H. Shimpo ◽  
K. Tanaka ◽  
...  
Keyword(s):  
Shear Stress ◽  
Cardiopulmonary Bypass ◽  
Membrane Skeleton ◽  
Platelet Glycoprotein ◽  
Platelet Surface ◽  
Platelet Aggregability ◽  
Vitro Model ◽  
Platelet Defects ◽  
Set Up

SummaryAlterations in platelet aggregability may play a role in the pathogenesis of qualitative platelet defects associated with cardiopulmonary bypass (CPB). We circulated fresh heparinized whole blood through tubing sets coated with heparin (C group, n = 10) and through non-coated sets (N group, n = 10) as a simulated CPB circuit. Shear stress (108 dyne/cm2)-induced platelet aggregation (hSIPA), plasma von Willebrand factor (vWF) activity and platelet glycoprotein (GP) Ib expression were measured, before, during, and after this in vitro set up of circulation. In the two groups, the extent of hSIPA significantly decreased during circulation and was partially restored after circulation. Decreases in the extent of hSIPA were significantly less with use of heparin-coated circuits. There was an equivalent reduction in plasma vWF activity, in the two groups. Expression of platelet surface GP Ib decreased significantly during circulation and recovered after circulation. Reduction of surface GP Ib expression during circulation was significantly less in the C group than that in the N group. Decrease in surface GP Ib expression correlated (r = 0.88 in either group) with the magnitude of hSIPA, in the two groups. The progressive removal of surface GP Ib was mainly attributed to redistribution of GP Ib from the membrane skeleton into the cytoskeleton. Our observations suggest that use of heparin-coated circuits partly blocks the reduction of hSIPA, as a result of a lesser degree of redistribution of GP Ib.

CONSERVATION OF RARE SPECIES PLANTS AND LICHENS IN SITU WITH PLANNED ANTHROPOGENIC ACTIVITIES: BASIC APPROACHES AND IMPLEMENTATION PRINCIPLES

2018 ◽  
Vol 12 (7-8) ◽  
pp. 38-45
Author(s):  
A. N. EFREMOV ◽  
N. V. PLIKINA ◽  
T. ABELI
Keyword(s):  
Rare Species ◽  
Technology Implementation ◽  
Technology Development ◽  
Anthropogenic Activities ◽  
Natural Habitat ◽  
Local Population ◽  
Main Stage ◽  
Social Risks

Rare species are most vulnerable to man-made impacts, due to their biological characteristics or natural resource management. As a rule, the economic impact is associated with the destruction and damage of individual organisms, the destruction or alienation of habitats. Unfortunately, the conservation of habitat integrity is an important protection strategy, which is not always achievable in the implementation of industrial and infrastructural projects. The aim of the publication is to summarize the experience in the field of protection of rare species in the natural habitat (in situ), to evaluate and analyze the possibility of using existing methods in design and survey activities. In this regard, the main methodological approaches to the protection of rare species in the natural habitat (in situ) during the proposed economic activity were reflected. The algorithm suggested by the authors for implementing the in situ project should include a preparatory stage (initial data collection, preliminary risk assessments, technology development, obtaining permitting documentation), the main stage, the content of which is determined by the selected technology and a long monitoring stage, which makes it possible to assess the effectiveness of the taken measures. Among the main risks of in situ technology implementation, the following can be noted: the limited resources of the population that do not allow for the implementation of the procedure without prior reproduction of individuals in situ (in vitro); limited knowledge of the biology of the species; the possibility of invasion; the possibility of crossing for closely related species that сo-exist in the same habitat; social risks and consequences, target species or population may be important for the local population; financial risks during the recovery of the population. The available experience makes it possible to consider the approach to the conservation of rare species in situ as the best available technology that contributes to reducing negative environmental risks.

Rapid, Refined, and Robust Method for Expression, Purification, and Characterization of Recombinant Human Amyloid-beta M1-42

2019 ◽  
Author(s):  
Priya Prakash ◽  
Travis Lantz ◽  
Krupal P. Jethava ◽  
Gaurav Chopra
Keyword(s):  
Amyloid Beta ◽  
Western Blots ◽  
Force Microscopy ◽  
E Coli ◽  
Atomic Force ◽  
Set Up ◽  
Short Time

Amyloid plaques found in the brains of Alzheimer’s disease (AD) patients primarily consists of amyloid beta 1-42 (Ab42). Commercially, Ab42 is synthetized using peptide synthesizers. We describe a robust methodology for expression of recombinant human Ab(M1-42) in Rosetta(DE3)pLysS and BL21(DE3)pLysS competent E. coli with refined and rapid analytical purification techniques. The peptide is isolated and purified from the transformed cells using an optimized set-up for reverse-phase HPLC protocol, using commonly available C18 columns, yielding high amounts of peptide (~15-20 mg per 1 L culture) in a short time. The recombinant Ab(M1-42) forms characteristic aggregates similar to synthetic Ab42 aggregates as verified by western blots and atomic force microscopy to warrant future biological use. Our rapid, refined, and robust technique to purify human Ab(M1-42) can be used to synthesize chemical probes for several downstream in vitro and in vivo assays to facilitate AD research.

Plant Biotechnology Workshop for High School Students

HortScience ◽  
1998 ◽  
Vol 33 (3) ◽  
pp. 504e-504
Author(s):  
Erika Szendrak ◽  
Paul E. Read ◽  
Jon S. Miller
Keyword(s):  
High School ◽  
High School Students ◽  
Medical Science ◽  
Plant Biotechnology ◽  
Plant Science ◽  
High School Biology ◽  
School Students ◽  
Subsequent Transformation ◽  
Set Up

Modern aspects of many subjects (e.g., computer science and some aspects of medical science) are now taught in many high schools, but the plant sciences are often given short shrift. A collaboration was therefore established with a high school biology program in which pilot workshops could be developed to enable advanced students to gain insights into modern plant science techniques. A successful example is the workshop on plant biotechnology presented in this report. This workshop is simple and flexible, taking into account that most high school biology laboratories and classrooms are not set up for sophisticated plant science/biotechnology projects. It is suitable for from 10 to 30 students, depending upon space and facilities available. Students work in pairs or trios, and learn simple disinfestation and transfer techniques for micropropagation and potential subsequent transformation treatments. Students gain insights into: sterile technique and hygiene; plant hormones and their physiological effects; plant cell, tissue and organ culture; the influence of environmental factors on response of cells and tissues cultured in vitro; and an understanding of the phenomenon of organogenesis and resulting plant growth and development. This workshop has been tested on several classes of students and following analysis, several refinements were included in subsequent iterations. Results of the students' experiments have been positive and instructive, with student learning outcomes above expectations. Further details of the workshop techniques and approach will be presented.

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