scholarly journals A Soft Spot for Chemistry–Current Taxonomic and Evolutionary Implications of Sponge Secondary Metabolite Distribution

Marine Drugs ◽  
2021 ◽  
Vol 19 (8) ◽  
pp. 448
Author(s):  
Adrian Galitz ◽  
Yoichi Nakao ◽  
Peter J. Schupp ◽  
Gert Wörheide ◽  
Dirk Erpenbeck

Marine sponges are the most prolific marine sources for discovery of novel bioactive compounds. Sponge secondary metabolites are sought-after for their potential in pharmaceutical applications, and in the past, they were also used as taxonomic markers alongside the difficult and homoplasy-prone sponge morphology for species delineation (chemotaxonomy). The understanding of phylogenetic distribution and distinctiveness of metabolites to sponge lineages is pivotal to reveal pathways and evolution of compound production in sponges. This benefits the discovery rate and yield of bioprospecting for novel marine natural products by identifying lineages with high potential of being new sources of valuable sponge compounds. In this review, we summarize the current biochemical data on sponges and compare the metabolite distribution against a sponge phylogeny. We assess compound specificity to lineages, potential convergences, and suitability as diagnostic phylogenetic markers. Our study finds compound distribution corroborating current (molecular) phylogenetic hypotheses, which include yet unaccepted polyphyly of several demosponge orders and families. Likewise, several compounds and compound groups display a high degree of lineage specificity, which suggests homologous biosynthetic pathways among their taxa, which identifies yet unstudied species of this lineage as promising bioprospecting targets.

2013 ◽  
Vol 87 (4) ◽  
pp. 550-569 ◽  
Author(s):  
Holly A. Schreiber ◽  
Maria Aleksandra Bitner ◽  
Sandra J. Carlson

Rhynchonellida is the stratigraphically oldest and phylogenetically most basal of the extant rhynchonelliform brachiopod orders, yet phylogenetic relationships among rhynchonellides are poorly known. The fourteen named rhynchonellide superfamilies (four of which have extant representatives) were defined primarily on the basis of features of the dorsal cardinalia, particularly crural morphology, but their homology and polarity have not been investigated rigorously. Superfamily monophyly is unclear, as is the evolution of several distinctive rhynchonellide morphological features, such as crura.The purpose of this study is to investigate the phylogenetic relationships among extant rhynchonellide genera using skeletal characters, and to compare the results with the current classification, elucidating the evolution of morphological features in the process. We completed parsimony-based and Bayesian analyses using fifty-eight characters of the interior and exterior of the shell that vary among the nineteen extant genera. Our results are readily interpretable with respect to the classification, and indicate that Hemithiridoidea, Dimerelloidea, and (in some analyses) Pugnacoidea appear to be monophyletic. Species classified in Dimerelloidea and Pugnacoidea, and in certain cases Hemithiridoidea, each form derived subclades that evolve from within a paraphyletic Norelloidea at the base of each subclade. Raduliform crura appear to be the most basal, phylogenetically; five other crural morphologies evolve from the raduliform state. However, morphological characters currently uniting genera in rhynchonellide superfamilies are not clearly diagnostic and exhibit a relatively high degree of homoplasy overall, suggesting that consistency with the classification may be based on a false sense of confidence in rhynchonellide morphology to clearly elucidate evolutionary relationships. Published molecular phylogenetic hypotheses conflict with the morphological topologies, further supporting this possibility.The evolutionary trends among diagnostic characters of Recent rhynchonellides appear to reflect successive juvenilization in adult morphology in several subclades, suggesting that heterochrony may have played an important role in the evolution of the group.


2020 ◽  
Vol 27 (14) ◽  
pp. 2335-2360 ◽  
Author(s):  
Chao Li ◽  
Dayong Shi

: Marine organisms are abundant sources of bioactive natural products. Among metabolites produced by sponges and their associated microbial communities, halogenated natural compounds accounted for an important part due to their potent biological activities. The present review updates and compiles a total of 258 halogenated organic compounds isolated in the past three decades, especially brominated derivatives derived from 31 genera of marine sponges. These compounds can be classified as the following classes: brominated polyunsaturated lipids, nitrogen compounds, brominated tyrosine derivatives and other halogenated compounds. These substances were listed together with their source organisms, structures and bioactivities. For this purpose, 84 references were consulted.


Agriculture ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 614
Author(s):  
Ayan Orazov ◽  
Liudmila Nadtochii ◽  
Kazybay Bozymov ◽  
Mariam Muradova ◽  
Araigul Zhumayeva

This paper examines the problem of food security in the Republic of Kazakhstan over the past 10 years. Based on statistical data, an assessment was made of the prevalence of malnutrition among the population of the country, including children under 5 years of age. There has been a trend towards for an improvement in the nutrition of the population for a few indicators; however, further optimization of food security indicators is required to achieve the goals of sustainable development (SDGs) of the FAO WHO Agenda for the period up to 2050 in Kazakhstan and in its individual regions. The paper reflects data on demographic changes over the past 10 years and its self-sufficiency in basic foods for 2019. A high degree of self-sufficiency in meat products (117.6%) is revealed in the population of the Republic of Kazakhstan. However, self-sufficiency in dairy products is at an extremely low level (0.1%). Camel breeding has been successfully developing in the country over the past 10 years. However, the number of camels in the country is still at a low level. Camel milk can be considered as a great source of macronutrients, its daily consumption partially facilitates the problem of Food Security in Kazakhstan.


2021 ◽  
pp. 205789112110192
Author(s):  
Peng Lin

Engaging in disaster relief and, more recently, post-disaster reconstruction in developing countries with critical geoeconomic and geopolitical interests has become an increasingly regular and institutionalized component of China’s evolving humanitarian diplomacy over the past decade. Drawn upon novel evidence from China’s growing disaster-related humanitarian assistance to Nepal and unprecedented engagement in Nepal’s long-term post-earthquake rebuild since 2015, this article explores the dynamics behind China’s transforming humanitarian diplomacy. The findings of this article suggest that: 1) geopolitical and geoeconomic interests, represented by the Belt-and-Road Initiative, serve as a critical driver for the development of China’s bilateral partnership with other countries in the disaster sector; 2) long-term cooperation with underdeveloped countries like Nepal provides China, both government and non-state actors (NSAs), with an effective channel to engage with the international humanitarian community and to internalize humanitarian norms; 3) although humanitarian missions remain contingent and instrumental in China’s international relations, they are laying the foundations for a specialized humanitarian policy area with more relevant normative assets, more professional actors, and more sophisticated institutions; 4) NSAs, represented by private foundations and civil NGOs, have played active roles in the state-dominant cooperation in disaster management. This article also suggests that intensified geopolitical confrontations, such as military clashes between India and China along their disputed borders over the past year, would lead to a high degree of politicization of humanitarian missions and partnerships counter-conducive to humanitarian goals.


1961 ◽  
Vol 51 (4) ◽  
pp. 755-764 ◽  
Author(s):  
G. B. Whitehead ◽  
J. A. F. Baker

Early in 1959, observations on the farm Tayside, in the East London district of South Africa, suggested that populations of the ‘two-host’ red tick, Rhipicephalns evertsi Neum., were more difficult to control with toxaphene preparations than they had been in the past. Resistance to toxaphene was suspected, and both field and laboratory experiments were carried out to investigate this possibility. Field trials indicated an increase in tolerance by Tayside populations of the tick to toxaphene, γ BHC and dieldrin, but showed no increased tolerance to sodium arsenite or DDT. Similar results were obtained in laboratory experiments where Tayside adults were compared with those of other populations of the tick known to be sensitive to insecticides. Laboratory experiments with larvae indicated a high degree of resistance to toxaphene and γ BHC in the Tayside population, but no increased tolerance to sodium arsenite, Delnav, Sevin or DDT could be detected. This pattern of cross-resistance is similar to that occurring in resistant populations of Boophilus dccoloratus(Koch).


2011 ◽  
Vol 25 (2) ◽  
pp. 244-271 ◽  
Author(s):  
Michal Kopeček

The article describes the rise and fall of the Civic Movement during the early 1990s, the most distinct post-dissident political group in Czech politics after 1989. Basically it follows two lines of enquiry. The first describes the post—Charter 77 community of people during the first years after the 1989 Czechoslovak democratic revolution, when strong personalities of the Czech culture and civic activism from its midst strove to cultivate a vision of “November 1989” in the nascent Czech democratic political culture and to promote the Velvet Revolution’s ethos as its base, first in the Civic Forum and later through one of the successor organisations, Civic Movement. Analysing the main reasons why these efforts were rather unsuccessful, the article turns to the “the politics of history” of the early Czechoslovak and Czech democracy. The “politics towards the past,” namely, turned out to be a soft spot of the post-dissident political elite and actually one of the main conflict points among the various cultural-political streams stemming from the former anticommunist opposition. The second line of enquiry focuses on this community’s half-hearted, if not even forced attempt at a political-ideological delineation heading towards socially conceived liberalism. The article describes how this attempt at recasting the “legacy” of former dissidence into a civic or social liberal political form also failed relatively soon due to the structural development of the Czech political system as well as internal ideological and political diversity of the Civic Movement.


Author(s):  
Delvin L. Krause

Stairways, steps, curbs and landings all relate to the pedestrian changing his respective elevation. The usual expectation is that this maneuver will occur as a result of a step up or down. When the physical environment deviates from the expected and/or standard dimensions a fall can occur, This monograph concerns itself with what exposures are generated when landing areas for stairs, steps and curbs and NOT STANDARD or as expected. Investigation of falls during the past thirty years indicates that the landing zone is an important element to consider in an accident investigation. Stairs, steps, curbs and ramps are all elements of our everyday lives. People manage to negotiate them with a high degree of success. They also manage to fall up them, down them and over them with an impressive rate of success as well. Stairs, steps, curbs and ramps sometimes exist in various combination with each other. This situation often results in an unsafe or accident producing condition.


1998 ◽  
Vol 79 (3) ◽  
pp. 204-210
Author(s):  
Yu. A. Chelyshev ◽  
K. I. Sitekulov

Over the past 25 years, laser radiation has found wide application in various fields of medicine, including neurology, mainly as a means of pain relief [17]. A high degree of specificity of the photobiological action is determined by its unique properties: monochromaticity, selective focus and coherence.


Zootaxa ◽  
2018 ◽  
Vol 4526 (3) ◽  
pp. 251 ◽  
Author(s):  
VIRGINIA LEÓN-RÈGAGNON ◽  
JANET TOPAN

Lung flukes of the genus Haematoloechus Looss, 1899 are common parasites of anurans worldwide, but the taxonomy of the group has been confusing. In this taxonomic revision, 89 species of Haematoloechus (= Pneumonoeces Looss, 1902, Ostioloides Odening, 1960, Ostiolum Pratt, 1903, Skrjabinoeces Sudarikov, 1950, Neohaematoloechus Odening, 1960, Metahaematoloechus Yamaguti, 1971) are listed. Of these, 70 are considered valid, three are species inquirendae (H. legrandi Mañé–Garzón & Gil, 1959, H. latoricensis Kozák, 1968 & H. vitelloconfluentum (Rai, 1962) Saeed, Al–Barwari & Al-Harmni, 2007), one is a nomen nudum H. sudarikovi Belouss, 1962, 14 are junior synonyms and one belongs to Ostioloides. This publication also describes three new species, H. occidentalis n. sp., H. veracruzanus n. sp. and H. mexicanus n. sp., parasitizing species of Rana Linnaeus in Mexico and redescribes Haematoloechus caballeroi (Skrjabin & Antipin, 1962) Yamaguti, 1971. The phylogenetic hypotheses based on sequences of mitochondrial and ribosomal DNA of Haematoloechus spp. show that genera proposed on the basis of morphological characters are not supported. The host records for species of Haematoloechus, together with the phylogenetic hypothesis of the genus, suggest that this host-parasite association predates the ranid diversification in the Cretaceous. 


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