scholarly journals One Century of Study: What We Learned about Paracoccidioides and How This Pathogen Contributed to Advances in Antifungal Therapy

2021 ◽  
Vol 7 (2) ◽  
pp. 106
Author(s):  
Erika Seki Kioshima ◽  
Patrícia de Souza Bonfim de Mendonça ◽  
Marcus de Melo Teixeira ◽  
Isis Regina Grenier Capoci ◽  
André Amaral ◽  
...  
Keyword(s):  
Latin America ◽  
Life Cycle ◽  
Antifungal Activity ◽  
Molecular Biology ◽  
Antifungal Therapy ◽  
High Toxicity ◽  
Development Stages ◽  
Thioredoxin System ◽  
Nanostructured Systems ◽  
Advanced Development

Paracoccidioidomycosis (PCM) is a notable fungal infection restricted to Latin America. Since the first description of the disease by Lutz up to the present day, Brazilian researchers have contributed to the understanding of the life cycle of this pathogen and provided the possibility of new targets for antifungal therapy based on the structural and functional genomics of Paracoccidioides. In this context, in silico approaches have selected molecules that act on specific targets, such as the thioredoxin system, with promising antifungal activity against Paracoccidioides. Some of these are already in advanced development stages. In addition, the application of nanostructured systems has addressed issues related to the high toxicity of conventional PCM therapy. Thus, the contribution of molecular biology and biotechnology to the advances achieved is unquestionable. However, it is still necessary to transcend the boundaries of synthetic chemistry, pharmaco-technics, and pharmacodynamics, aiming to turn promising molecules into newly available drugs for the treatment of fungal diseases.

Phytochemical Constituents of Tulbaghia violacea Harv Extract and its Antifungal Potential Against Cryptococcus neoformans and Cryptococcus gattii

2019 ◽  
Vol 9 (4) ◽  
pp. 330-340
Author(s):  
Mitradev Pattoo ◽  
Vuyokazi Belewa ◽  
Benesh Munilal Somai
Keyword(s):  
Antifungal Activity ◽  
Cryptococcus Neoformans ◽  
Antifungal Therapy ◽  
Developing World ◽  
Chemical Constituents ◽  
Cryptococcus Gattii ◽  
Plant Part ◽  
Aqueous Extracts ◽  
Antifungal Activities ◽  
Antifungal Potential

Background:In both the developed and developing world, the mortality rates of people afflicted with cryptococcosis are unacceptably high despite the availability of antifungal therapy. The disease is caused by Cryptococcus neoformans (predominantly in immunocompromised individuals) and by Cryptococcus gattii. Globally the disease is estimated to cause around 600,000 deaths annually. Antifungal therapy is available, but in the developing world, may be unaffordable to many people, there is an increasing threat of resistance to the available drugs and our repertoire of antifungal drugs is very limited. Consequently, more research has been focusing on the use of medicinal plants as therapeutic agents. The originality of the current study is that although Tulbaghia violacea is a well-documented medicinal plant, the chemical composition of aqueous extracts and their antifungal potential against pathogenic yeasts are unknown. This is the first study that evaluates the chemical constituents of aqueous T. violacea root, leaf, rhizome and tuber extracts and their corresponding antifungal activities against C. neoformans and C. gattii.Objectives:The study aimed to investigate the phytochemical composition and antifungal potential of Tulbaghia violacea root, leaf, rhizome and tuber extracts against Cryptococcus neoformans and Cryptococcus gattii.Methods:Roots, leaves, rhizomes and tubers were extracted with water only for 48 h at room temperature with continuous shaking. Extracts were filter sterilized, freeze-dried and, chemically analyzed for saponin, flavonol, phenolic and tannin content. Chemical constituents of each extract were also identified by GC-MS analysis. The Minimum Inhibitory Concentration (MIC) of suitably diluted extracts of each plant part were also performed against C. neoformans and C. gattii, yeast pathogens commonly associated with HIV/AIDS sufferers.Results:Phytochemical analysis showed different concentrations of saponins (between 1023 and 2896.73 µg/ml), phenolics (between 16.48 and 51.58 µg/ml) and tannins (between 122.30 and 543.07 µg/ml) present in the different extracts. No flavonols were detected. GC-MS analysis identified a complex mixture of phytochemicals composed predominantly of sulphide, pyran, furan and ketone containing compounds to be present in the different plant parts. All extracts were dominated by the presence of 4 H-pyran-4-one, 2,3-dihydro-3,5-dihydroxy-6-methyl, a pyran known to have antifungal properties. Although the root, leaf, rhizome and tuber extracts exhibited antifungal activities against both fungi, the rhizome and tuber extract were found to possess the lowest MIC’s of 1.25 mg/ml and 2.5 mg/ml against Cryptococcus neoformans and Cryptococcus gattii respectively.Conclusion:T. violacea extracts have a complex constituent of phytochemicals and each plant part exhibited a strong antifungal activity against C. neoformans and C. gattii. The rhizome and tuber extracts showed the highest antifungal activity against C. neoformans and C. gattii respectively. Thus, T. violacea aqueous extracts are strong candidates for further development into an antifungal chemotherapeutic agent.

scholarly journals Biological aspects of Hylesia metapyrrha (Lepidoptera; Saturniidae; Hemileucinae), in laboratory

2007 ◽  
Vol 67 (1) ◽  
pp. 173-177 ◽  
Author(s):  
A. Specht ◽  
AC. Formentini ◽  
E. Corseuil
Keyword(s):  
Life Cycle ◽  
Incubation Period ◽  
Adult Stage ◽  
Immature Stages ◽  
Average Period ◽  
Development Stages ◽  
Behavioral Aspects ◽  
Biological Aspects ◽  
Guava Leaves

The aim of this work was to study biological aspects and the life cycle of Hylesia Metapyrrha in a laboratory. Laboratorial breeding was made at 25 ± 1 °C, 70 ± 10% UR and 14 hours of photophase, feeding the larvae with guava leaves (Psidium guayava L. - Myrtaceae). Time was evaluated on the days of all the development stages; morphometry was evaluated in millimeters and the pupa’s mass in grams. The eggs were disposed in groups and covered by urticating abdominal hair. The incubation period lasted 52 days. The larvae, with gregarious habits, presented background black coloration, yellowish scoli and two orange longitudinal lines above and below the spiracles, during the development which lasted an average period of 74.59 days and went through seven instars. The pre-pupa and the pupa stages lasted on average 8.82 and 50.56 days, respectively; the female pupae presented a duration, weight and size which was significantly bigger. The adult stage lasted on average 5.50 days with periods of pre, post and oviposition of 2.30, 1.90 and 1.00 days, respectively. This study broadens the knowledge of the immature stages, biological, morphological and behavioral aspects, until then restricted to the morphology and to registers of the occurrence of the adult forms.

Restrictions of access to pesticides in suicide prevention

2021 ◽  
pp. 713-718
Author(s):  
Michael R. Phillips ◽  
David Gunnell
Keyword(s):  
Latin America ◽  
Suicide Prevention ◽  
Eastern Mediterranean ◽  
Global Burden ◽  
Organophosphate Pesticides ◽  
High Toxicity ◽  
Suicide Rates ◽  
Intentional Ingestion ◽  
Methods Of Suicide ◽  
The Western Pacific

Intentional pesticide ingestion is a common method of suicide, accounting for up to one-fifth of all suicides worldwide. The importance of intentional ingestion of pesticides was initially recognized in Asia and the Western Pacific but it is also a problem in Latin America, the Eastern Mediterranean, and in Africa. Organophosphate pesticides are responsible for a large proportion of pesticide self-poisonings and for the majority of deaths from pesticide ingestion. Limiting access to pesticides could substantially reduce the global burden of mortality due to suicide. Despite initial enthusiasm for restricting access to pesticides by promoting safe storage of these compounds, the definitive study on this method in Sri Lanka did not find a significant reduction in suicide rates. There is, however, growing evidence that national or regional bans on high toxicity pesticides lead to falls in pesticide-ingestion suicide rates, and overall, suicide rates without substantial substitution of other methods of suicide.

scholarly journals An Analytical Model of Tourist Destination Development and Characteristics of the Development Stages: Example of the Island of Bornholm

2019 ◽  
Vol 11 (24) ◽  
pp. 6989
Author(s):  
Adam R. Szromek
Keyword(s):  
Sustainable Development ◽  
Life Cycle ◽  
Business Models ◽  
Logistic Function ◽  
Tourist Industry ◽  
Tourist Destination ◽  
Tourist Attractions ◽  
Development Stages ◽  
Stage Of Development ◽  
The 1960S

This paper presents the basis of the tourism area life cycle (TALC) concept and its extension in the context of the implementation of sustainable development practices in the tourist business model. The author uses the logistic function to determine the level of tourist absorption and capacity. The empirical basis of the methods used was statistics on the development of the tourist industry on Bornholm. The objective of the paper is to determine the stage of development of the tourist area of Bornholm and the consequences of this stage for business models of tourist enterprises functioning there. The results of the analysis indicate that the range of tourist absorption was reached in the 1960s–1970s, and that it is currently getting closer to the upper threshold of that range. Tourism on Bornholm, in line with the TALC concept, is currently in the stabilization stage. Future tourist trends on Bornholm depend on many factors; however, if tourist development goes into the decline stage, the offered products may require transformation, in terms of both transport and the form and availability of tourist attractions. Perhaps this will involve a total transformation of the island into a facility with a specific entertainment, leisure, or business profile. The listed solutions will require entrepreneurs to react within the scope of a transformation of their business models into sustainable models of tourist business.

scholarly journals Poly-ε-caprolactone Nanoparticles Loaded with 4-Nerolidylcatechol (4-NC) for Growth Inhibition of Microsporum canis

Antibiotics ◽  
2020 ◽  
Vol 9 (12) ◽  
pp. 894
Author(s):  
Vanessa Raquel Greatti ◽  
Fernando Oda ◽  
Rodrigo Sorrechia ◽  
Bárbara Regina Kapp ◽  
Carolina Manzato Seraphim ◽  
...  
Keyword(s):  
Antifungal Activity ◽  
Growth Inhibition ◽  
Fungal Infections ◽  
Polymeric Nanoparticles ◽  
Weight Ratio ◽  
Microsporum Canis ◽  
Nanostructured Systems ◽  
The Stability

Dermatophyte fungal infections are difficult to treat because they need long-term treatments. 4-Nerolidylcatechol (4-NC) is a compound found in Piper umbellatum that has been reported to demonstrate significant antifungal activity, but is easily oxidizable. Due to this characteristic, the incorporation in nanostructured systems represents a strategy to guarantee the compound’s stability compared to the isolated form and the possibility of improving antifungal activity. The objective of this study was to incorporate 4-NC into polymeric nanoparticles to evaluate, in vitro and in vivo, the growth inhibition of Microsporum canis. 4-NC was isolated from fresh leaves of P. umbellatum, and polymer nanoparticles of polycaprolactone were developed by nanoprecipitation using a 1:5 weight ratio (drug:polymer). Nanoparticles exhibited excellent encapsulation efficiency, and the antifungal activity was observed in nanoparticles with 4-NC incorporated. Polymeric nanoparticles can be a strategy employed for decreased cytotoxicity, increasing the stability and solubility of substances, as well as improving the efficacy of 4-NC.

Nematodes associated with damage in oilseed rape: new data on the biology and geographical distribution of Meloidogyne artiellia

Nematology ◽  
2014 ◽  
Vol 16 (2) ◽  
pp. 201-206
Author(s):  
Alain Buisson ◽  
Andre Chabert ◽  
Laurent Ruck ◽  
Sylvain Fournet
Keyword(s):  
Life Cycle ◽  
Oilseed Rape ◽  
Atlantic Coast ◽  
Parasitic Nematodes ◽  
Paris Basin ◽  
Plant Parasitic Nematodes ◽  
Mediterranean Species ◽  
Climate Conditions ◽  
Development Stages ◽  
Plant Parasitic

For several years, patches of plants presenting deficiencies in growth have been observed in fields cultivated with oilseed rape. Over 3 years, 57 pairs of damaged and undamaged plants were sampled from cultivated fields on the Atlantic coast of France and around the Paris basin. Results show that two main species of plant-parasitic nematodes can be associated with the patches, Heterodera cruciferae and Meloidogyne artiellia, and that both species probably do not occur in the same fields and regions. This means that M. artiellia, which is considered as a Mediterranean species causing damage essentially on wheat, is also well adapted to colder climate conditions and can extensively damage oilseed rape. Monitoring the different development stages of M. artiellia in a field cultivated with oilseed rape provided more information about the life cycle and showed that only one generation can develop between the sowing in autumn and April.

scholarly journals Pools and rapids as spawning and nursery areas for fish in a river stretch without floodplains

2014 ◽  
Vol 12 (3) ◽  
pp. 611-622 ◽  
Author(s):  
Sunshine de Ávila-Simas ◽  
David Augusto Reynalte-Tataje ◽  
Evoy Zaniboni-Filho
Keyword(s):  
Feeding Activity ◽  
Light Trap ◽  
Initial Growth ◽  
Fish Reproduction ◽  
Monthly Basis ◽  
Development Stages ◽  
River Stretch ◽  
Advanced Stages ◽  
Advanced Development ◽  
Uruguay River

This study aimed to evaluate the importance of two environments situated in the main channel of the Peixe River (a tributary of the upper Uruguay River) on fish reproduction and initial growth. Ichthyoplankton, macrozooplankton, and zoobenthos collections were taken on a monthly basis from October 2011 to March 2012, sampling a rapids and a pool environment. The instrument used for the capture of the ichthyoplankton in both environments was a light trap. In total, 795 eggs and 274 larvae were captured. The species that presented higher abundance and occurrence frequency out of the total captured in both environments were Leporinus obtusidens, Bryconamericus iheringii, and Bryconamericus stramineus. The evaluation of the feeding activity reveals a major repletion degree of the larvae in more advanced stages in the pool. The pool environment presented a higher abundance of larvae in more advanced development stages. We conclude that the channel of the Peixe River is important for the reproduction and initial growth of fish and that each river environment seems to fulfill a different role in the life cycle of the ichthyoplankton community.

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