A virulent strain German bacteriology as scientific racism, 1890–1920

2002 ◽  
pp. 218-234
Author(s):  
Paul Weindling
Keyword(s):  
Virulent Strain ◽  
Scientific Racism

Protective effect of Trypanosoma rangeli against infections with a highly virulent strain of Trypanosoma cruzi

1997 ◽  
Vol 2 (5) ◽  
pp. 482-487 ◽  
Author(s):  
Claudio Zuniga ◽  
Teresa Palau ◽  
Pilar Penin ◽  
Carlos Gamallo ◽  
Jose Antonio de Diego
Keyword(s):  
Trypanosoma Cruzi ◽  
Protective Effect ◽  
Virulent Strain ◽  
Trypanosoma Rangeli ◽  
Highly Virulent

Chronic infection with Toxoplasma gondii does not prevent acute disease after virulent strain reinfection in experimental mice

2018 ◽  
Vol 11 (3) ◽  
pp. 149-154
Author(s):  
Eman Gaballah ◽  
Aida Abdel-Magied ◽  
Nora Aboulfotouh ◽  
Goman Elganainy
Keyword(s):  
Toxoplasma Gondii ◽  
Chronic Infection ◽  
Virulent Strain ◽  
Acute Disease

In Vitro, In Silico and Ex Vivo Studies of Dihydroartemisinin Derivatives as Antitubercular Agents

2019 ◽  
Vol 19 (8) ◽  
pp. 633-644 ◽  
Author(s):  
Komal Kalani ◽  
Sarfaraz Alam ◽  
Vinita Chaturvedi ◽  
Shyam Singh ◽  
Feroz Khan ◽  
...  
Keyword(s):  
Bone Marrow ◽  
In Silico ◽  
Ex Vivo ◽  
Virulent Strain ◽  
Infection Model ◽  
Mouse Bone Marrow ◽  
Significant Activity ◽  
Macrophage Infection ◽  
In Silico Studies

Introduction: As a part of our drug discovery program for anti-tubercular agents, dihydroartemisinin (DHA-1) was screened against Mtb H37Rv, which showed moderate anti-tubercular activity (>25.0 µg/mL). These results prompted us to carry out the chemical transformation of DHA-1 into various derivatives and study their antitubercular potential. Materials and Methods: DHA-1 was semi-synthetically converted into four new acyl derivatives (DHA-1A – DHA-1D) and in-vitro evaluated for their anti-tubercular potential against Mycobacterium tuberculosis H37Rv virulent strain. The derivatives, DHA-1C (12-O-(4-nitro) benzoyl; MIC 12.5 µg/mL) and DHA-1D (12-O-chloro acetyl; MIC 3.12µg/mL) showed significant activity against the pathogen. Results: In silico studies of the most active derivative (DHA-1D) showed interaction with ARG448 inhibiting the mycobacterium enzymes. Additionally, it showed no cytotoxicity towards the Vero C1008 cells and Mouse bone marrow derived macrophages. Conclusion: DHA-1D killed 62% intracellular M. tuberculosis in Mouse bone marrow macrophage infection model. To the best of our knowledge, this is the first-ever report on the antitubercular potential of dihydroartemisinin and its derivatives. Since dihydroartemisinin is widely used as an antimalarial drug; these results may be of great help in anti-tubercular drug development from a very common, inexpensive, and non-toxic natural product.

Preparation and Antitubercular Activities of Palindromic Hydrazinecarbothioamides and Carbonothioic Dihydrazides

2019 ◽  
Vol 16 (11) ◽  
pp. 1202-1210 ◽  
Author(s):  
Michael Joseps Hearn ◽  
Gwendolyn Towers ◽  
Michael Henry Cynamon
Keyword(s):  
High Resolution Mass Spectrometry ◽  
Virulent Strain ◽  
Chemotherapeutic Agents ◽  
Disc Diffusion ◽  
Global Public Health ◽  
Health Crisis ◽  
Chemical Structures ◽  
Public Health Crisis ◽  
Zones Of Inhibition ◽  
Diffusion Assay

Background:With approximately one-third of the world’s population infected, tuberculosis continues to be a global public health crisis. The rise of strains that are unusually virulent or highly resistant to current drugs is a cause of special concern, prompting research into new classes of compounds, as well as the re-evaluation of known chemotherapeutic agents.Objectives:The antimycobacterial activities associated with some recently-reported thiocarbonyl compounds kindled our interest in the synthesis of substituted hydrazinecarbothioamides (3) and carbonothioic dihydrazides (4), with the aim of investigating their potential in antitubercular drug design and discovery.Methods:In the present study, the title compounds 3 and 4 were prepared by the condensation of hydrazines with isothiocyanates in reactions readily controlled by stoichiometry, temperature and solvent. The compounds were assessed against Mycobacterium bovis BCG in Kirby-Bauer disc diffusion, and minimum inhibitory concentrations were determined against the virulent strain M. tuberculosis Erdman.Results:The chemical structures of these thermally stable compounds were determined by IR, 1HNMR, 13C-NMR, high-resolution mass spectrometry and elemental analysis. In the Kirby-Bauer disc diffusion assay, some of the compounds showed substantial diameters of inhibition against BCG. In some cases, the zones of inhibition were so large that no growth at all was observed on the assay plates. Against M. tuberculosis Erdman, several of the compounds showed significant activities. Compound 3h was the most active, demonstrating a minimum inhibitory concentration of 0.5 µg/mL.Conclusion:We found that the title compounds may be prepared conveniently in excellent purity and good yields. They are readily identified on the basis of their characteristic spectra. Some members of this class showed significant activities against mycobacteria. We conclude that further work will be warranted in exploring the antitubercular properties of these compounds.

Evaluation of the growth and sporulation of different entomopathogenic fungi in different liquid and solid media at varied concentrations

2017 ◽  
Vol 6 (8) ◽  
pp. 5459
Author(s):  
Chandra Teja K. ◽  
Rahman S. J.
Keyword(s):  
Entomopathogenic Fungi ◽  
Large Scale ◽  
Insect Pests ◽  
Culture Media ◽  
Virulent Strain ◽  
Carbon Sources ◽  
Nitrogen Sources ◽  
Maximum Growth ◽  
Nutritional Requirements ◽  
Virulent Strains

Entomopathogenic fungi like Beauveria bassiana, Metarhizium anisopliae and Lecanicillium lecanii are used in biological control of agricultural insect pests. Their specific mode of action makes them an effective alternative to the chemical Insecticides. Virulent strains of Entomopathogenic fungi are effectively formulated and used as bio-insecticides world-wide. Amenable and economical multiplication of a virulent strain in a large scale is important for them to be useful in the field. Culture media plays a major role in the large-scale multiplication of virulent strains of Entomopathogens. Different substrates and media components are being used for this purpose. Yet, each strain differs in its nutritional requirements for the maximum growth and hence it is necessary to standardize the right components and their optimum concentrations in the culture media for a given strain of Entomopathogen. In the current study, three different nitrogen sources and two different carbon sources were tried to standardize the mass multiplication media for seven test isolates of Entomopathogenic fungi. A study was also conducted to determine the ideal grain media for the optimum conidial yields of the test isolates. Yeast extract was found to be the best Nitrogen source for the isolates. The isolates tested, differed in their nutritional requirements and showed variation in the best nitrogen and carbon sources necessary for their growth. Variation was also found in the optimum concentration of both the ingredients for the growth and sporulation of the isolates. In the solid-state fermentation study, rice was found to be the best grain for the growth of most of the fungi followed by barley. The significance of such a study in the development of an effective Myco-insecticide is vital and can be successfully employed in agriculture is discussed.

“La Idea Mueve” (The Idea Moves Us)

2018 ◽  
Author(s):  
Gabriela González
Keyword(s):  
United States ◽  
Mexican American ◽  
The United States ◽  
Mexican Immigrant ◽  
Democratic Institutions ◽  
Scientific Racism ◽  
Men And Women ◽  
Political Beliefs ◽  
Age Of Enlightenment

The concluding chapter explains how race had served defenders of slavery by providing them with an excuse to hold men and women in bondage. For their inhumane treatment of Africans during the Age of Enlightenment to be justified, their humanity needed to be ideologically stripped away—scientific racism served that purpose. Racist theories also kept other groups in subaltern positions. Mexicans with mestizo, mulatto, and Indian genealogies experienced racialization in the United States. Simply put, Americans, proud of their liberal political heritage and their democratic institutions, needed to see oppressed groups as somehow sub-human in order to reconcile their political beliefs with the nation’s less than egalitarian realities. It is for this reason that the politics of redemption practiced by Mexican immigrant and Mexican American activists merits attention.

scholarly journals Effects of Green Alga, Chaetomorpha aerea Extract on Non-Specific Immune Responses and Disease Resistance against Edwardsiella tarda Infection in Labeo rohita

2021 ◽  
Vol 11 (10) ◽  
pp. 4325
Author(s):  
Govindharajan Sattanathan ◽  
Vairakannu Tamizhazhagan ◽  
Nadeem Raza ◽  
Syed Qaswar Ali Shah ◽  
Muhammad Zubair Hussain ◽  
...  
Keyword(s):  
Immune Responses ◽  
Green Alga ◽  
Labeo Rohita ◽  
Virulent Strain ◽  
Edwardsiella Tarda ◽  
Fish Mortality ◽  
Control Group ◽  
Physiological Salt Solution ◽  
Myeloperoxidase Activity ◽  
Chaetomorpha Aerea

The current study evaluated the effects of a methanol extract from Chaetomorpha aerea (a green alga) on non-specific immune responses and resistance against Edwardsiella tarda infection in Labeo rohita. Different doses of the extract (5, 50 and 500 mg/kg of body weight) were injected into the fish intraperitoneally while a control group was injected with 0.2 mL of sterile physiological salt solution. Variations in several immunostimulatory parameters (i.e., neutrophil, serum lysozyme, myeloperoxidase, serum antiprotease, and ceruloplasmin activity), reactive oxygen species (ROS) and reactive nitrogen species (RNS) were assessed after 7, 14, 21, and 28 days of post stimulation. E. tarda culture was injected into the fish after 28 days of post stimulation to induce infection to monitor fish mortality within 14 days. Interestingly, all doses of methanolic extract enhanced neutrophil, lysozyme, and myeloperoxidase activity, ROS and RNS, while a dose of 50 mg/kg was the most effective. Fish injected with this optimal dose were also protected against infection with virulent strain of E. tarda. The results of the study suggest that C. aerea extract is a potential prophylactic agent against bacterial infections in finfish.

scholarly journals Identification of Putative Virulence Genes by DNA Methylation Studies in the Cereal Pathogen Fusarium graminearum

Cells ◽  
2021 ◽  
Vol 10 (5) ◽  
pp. 1192
Author(s):  
Francesco Tini ◽  
Giovanni Beccari ◽  
Gianpiero Marconi ◽  
Andrea Porceddu ◽  
Micheal Sulyok ◽  
...  
Keyword(s):  
Dna Methylation ◽  
Fusarium Graminearum ◽  
Environmental Changes ◽  
Virulent Strain ◽  
Fungal Virulence ◽  
Wheat Seedlings ◽  
Wide Range ◽  
Conidia Production ◽  
Natural Hosts

DNA methylation mediates organisms’ adaptations to environmental changes in a wide range of species. We investigated if a such a strategy is also adopted by Fusarium graminearum in regulating virulence toward its natural hosts. A virulent strain of this fungus was consecutively sub-cultured for 50 times (once a week) on potato dextrose agar. To assess the effect of subculturing on virulence, wheat seedlings and heads (cv. A416) were inoculated with subcultures (SC) 1, 23, and 50. SC50 was also used to re-infect (three times) wheat heads (SC50×3) to restore virulence. In vitro conidia production, colonies growth and secondary metabolites production were also determined for SC1, SC23, SC50, and SC50×3. Seedling stem base and head assays revealed a virulence decline of all subcultures, whereas virulence was restored in SC50×3. The same trend was observed in conidia production. The DNA isolated from SC50 and SC50×3 was subject to a methylation content-sensitive enzyme and double-digest, restriction-site-associated DNA technique (ddRAD-MCSeEd). DNA methylation analysis indicated 1024 genes, whose methylation levels changed in response to the inoculation on a healthy host after subculturing. Several of these genes are already known to be involved in virulence by functional analysis. These results demonstrate that the physiological shifts following sub-culturing have an impact on genomic DNA methylation levels and suggest that the ddRAD-MCSeEd approach can be an important tool for detecting genes potentially related to fungal virulence.

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