The genus Segestria Latreille, 1804 and the species Segestria florentina (Rossi, 1790) are recorded in Libya for the first time, based on a single adult female specimen

Abstract

Seven male specimens (one immature and six adults) of a rare species of Loureedia jerbae (El-Hennawy, 2005), are recorded for the first time in Libya, representing the first record of this species outside of Tunisia. Illustrations and a description are provided. Only the most recent adult of the specimens captured in October/November of 2019 to 2022 was examined, identified and described. Although Libya has one of the least recorded spider species in the Mediterranean region, it is promising to reveal more undiscovered and undocumented species through extensive research in this large country

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Using macroinvertebrate-based biotic indices and diversity indices to assess water quality: A case study on the Karasu Stream (Kastamonu, Türkiye)

İbrahim Küçükbasmacı, Abdulhamed M Omar Etriieki

Biomonitoring is an approach that uses indicators or sentinel species to assess the health or pollution of an environment, combining diversity based on specific taxonomic groups with the taxa’s indicator of pollution into a single index or score. Benthic macroinvertebrates are among the most preferred and valuable indicators of the biotic index. Our study aims to evaluate water quality and ecological status using biotic and diversity indices based on benthic macroinvertebrates. The macroinvertebrate samples used in this study were collected seasonally from 16 stations determined in Karasu Stream. These samples consist of 14747 specimens belonging to 9 orders and 40 families of Insecta, Malacostraca, Hirudinea and Oligochaeta. In addition, some physicochemical parameters were measured at the stations. The data obtained were analyzed using the Turkey-Biological Monitoring Working Group (TR-BMWP), Average Score per Taxon (ASPT), Family Biotic Index (FBI), Ephemeroptera, Plecoptera, and Trichoptera (EPT) taxon richness index, and Shannon-Wiener (SWDI), Simpson (SDI) and Hill’s diversity indices. Our results showed that the last six stations of Karasu Stream were under pressure due to various anthropogenic effects. According to biotic indexes, the ecological quality status of the water in the stations was determined to be High or Good in the first ten stations and Average, Poor, or Bad in the last six stations. The results of our study showed that TR-BMWP, FBI, and EPT indices are more reliable in determining water quality than the ASPT index and reflect the environmental situation better. Since the TR-BMWP index is adapted to macroinvertebrate taxa distributed in Türkiye, it can be used as a suitable tool for evaluating other rivers’ water quality in Türkiye.

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Using macroinvertebrate‐based biotic indices and diversity indices to assess water quality: A case study on the Karasu Stream (Kastamonu, Türkiye)

Abdulhamed M Omar Etriieki, İbrahim Küçükbasmacı

Ecohydrology, e2627, 2024

Biomonitoring is an approach that uses indicators or sentinel species to assess the health or pollution of an environment, combining diversity based on specific taxonomic groups with the taxa's indicator of pollution into a single index or score. Benthic macroinvertebrates are among the most preferred and valuable indicators of the biotic index. Our study aims to evaluate water quality and ecological status using biotic and diversity indices based on benthic macroinvertebrates. The macroinvertebrate samples used in this study were collected seasonally from 16 stations determined in Karasu Stream. These samples consist of 14,747 specimens belonging to 9 orders and 40 families of Insecta, Malacostraca, Hirudinea and Oligochaeta. In addition, some physicochemical parameters were measured at the stations. The data obtained were analysed using the Turkey‐Biological Monitoring Working Group (TR‐BMWP), Average Score per Taxon (ASPT), Family Biotic Index (FBI), Ephemeroptera, Plecoptera and Trichoptera (EPT) taxon richness index, and Shannon–Wiener, Simpson and Hill's diversity indices. Our results showed that the last six stations of Karasu Stream were under pressure due to various anthropogenic effects. According to biotic indexes, the ecological quality status of the water in the stations was determined to be high or good in the first 10 stations and average, poor or bad in the last 6 stations. The results of our study showed that TR‐BMWP, FBI and EPT indices are more reliable in determining water quality than the ASPT index and reflect the environmental situation better. Since the TR‐BMWP index is adapted to macroinvertebrate taxa distributed in Türkiye, it can be used as a suitable tool for evaluating other rivers' water quality in Türkiye.

Description

Background and aims

The physical parameters and the occurrence and abundance of zooplankton in Ain-Zayanah lagoon, Benghazi, Libya, were studied from August, 2005–July, 2006, as a part of detailed investigation on the feasibility of converting the lagoon into an aquaculture farm for captive breeding and culturing of different economically important edible fish, fish fry, molluscan and crustacean animals, and for culturing the zooplankton which form the food of these organisms.

Methods

Five different sites located near to the shore were selected in the lagoon for water and zooplankton monthly sampling and analyses. The physical parameters of the water included air and water temperatures, transparency, electrical conductivity, total dissolved solids, pH, dissolved oxygen and total hardness; they were analysed using standard methods. Various differences were revealed in the relationships of these parameters in and between sites, months and seasons.

Results

Seven major groups of zooplankton inhabited Ain-Zayanah lagoon; rotifers formed the dominant one (40.50%), followed by rhabtida (21.61%), crustacean larva (14.55%), foraminifera (13.23%), ostracoda (5.97%), copepoda (4.13%) and cladocera (0.01%). Air and water temperatures, pH, DO, electrical conductivity, TDS and hardness had different relationships with the seven zooplankton groups in Ain-Zayanah lagoon.

Conclusion

The results obtained were discussed extensively in the light of available literature in the fields, and suitable conclusions, suggestions and precautions to be taken were given in connection with the establishment of Aquaculture farm in Ain-Zayanah lagoon

Leishmania pyrimidine salvage is replete with opportunities for therapeutic intervention with enzyme inhibitors or antimetabolites. Their uptake into cells depends upon specific transporters; therefore it is essential to establish whether various Leishmania species possess similar pyrimidine transporters capable of drug uptake. Here, we report a comprehensive characterization of pyrimidine transport in L. major and L. mexicana. In both species, two transporters for uridine/adenosine were detected, one of which also transported uracil and the antimetabolites 5-fluoruracil (5-FU) and 5F,2'deoxyuridine (5F,2'dUrd), and was designated uridine-uracil transporter 1 (UUT1); the other transporter mediated uptake of adenosine, uridine, 5F,2'dUrd and thymidine and was designated Nucleoside Transporter 1 (NT1). To verify the reported L. donovani model of two NT1-like genes encoding uridine/adenosine transporters, and an NT2 gene encoding an inosine transporter, we cloned the corresponding L. major and L. mexicana genes, expressing each in T. brucei. Consistent with the L. donovani reports, the NT1-like genes of either species mediated the adenosine-sensitive uptake of [3H]-uridine but not of [3H]-inosine. Conversely, the NT2-like genes mediated uptake of [3H]-inosine but not [3H]-uridine. Among pyrimidine antimetabolites tested, 5-FU and 5F,2'dUrd were the most effective antileishmanials; resistance to both analogs was induced in L. major and L. mexicana. In each case it was found that the resistant cells had lost the transport capacity for the inducing drug. Metabolomics analysis found that the mechanism of action of 5-FU and 5F-2'dUrd was similar in both Leishmania species, with major changes in deoxynucleotide metabolism. We conclude that the pyrimidine salvage system is highly conserved in Leishmania species - essential information for the development of pyrimidine-based chemotherapy.

One of the most promising new targets for trypanocidal drugs to emerge in recent years is the cyclic AMP (cAMP) phosphodiesterase (PDE) activity encoded by TbrPDEB1 and TbrPDEB2. These genes were genetically confirmed as essential, and a highaffinity inhibitor, CpdA, displays potent antitrypanosomal activity. To identify effectors of the elevated cAMP levels resulting from CpdA action and, consequently, potential sites for adaptations giving resistance to PDE inhibitors, resistance to the drug was induced. Selection of mutagenized trypanosomes resulted in resistance to CpdA as well as cross-resistance to membranepermeable cAMP analogues but not to currently used trypanocidal drugs. Resistance was not due to changes in cAMP levels or in PDEB genes. A second approach, a genome-wide RNA interference (RNAi) library screen, returned four genes giving resistance to CpdA upon knockdown. Validation by independent RNAi strategies confirmed resistance to CpdA and suggested a role for the identified cAMP Response Proteins (CARPs) in cAMP action. CARP1 is unique to kinetoplastid parasites and has predicted cyclic nucleotide binding-like domains, and RNAi repression resulted in >100-fold resistance. CARP2 and CARP4 are hypothetical conserved proteins associated with the eukaryotic flagellar proteome or with flagellar function, with an orthologue of CARP4 implicated in human disease. CARP3 is a hypothetical protein, unique to Trypanosoma. CARP1 to CARP4 likely represent components of a novel cAMP signaling pathway in the parasite. As cAMP metabolism is validated as a drug target in Trypanosoma brucei, cAMP effectors highly divergent from the mammalian host, such as CARP1, lend themselves to further pharmacological development

Background: African trypanosomes are capable of both pyrimidine biosynthesis and salvage of preformed pyrimidines from the host, but it is unknown whether either process is essential to the parasite. Methodology/Principal Findings: Pyrimidine requirements for growth were investigated using strictly pyrimidine-free media, with or without single added pyrimidine sources. Growth rates of wild-type bloodstream form Trypanosoma brucei brucei were unchanged in pyrimidine-free medium. The essentiality of the de novo pyrimidine biosynthesis pathway was studied by knocking out the PYR6-5 locus that produces a fusion product of orotate phosphoribosyltransferase (OPRT) and Orotidine Monophosphate Decarboxylase (OMPDCase). The pyrimidine auxotroph was dependent on a suitable extracellular pyrimidine source. Pyrimidine starvation was rapidly lethal and non-reversible, causing incomplete DNA content in new cells. The phenotype could be rescued by addition of uracil; supplementation with uridine, 29deoxyuridine, and cytidine allowed a diminished growth rate and density. PYR6-52/ 2 trypanosomes were more sensitive to pyrimidine antimetabolites and displayed increased uracil transport rates and uridine phosphorylase activity. Pyrimidine auxotrophs were able to infect mice although the infection developed much more slowly than infection with the parental, prototrophic trypanosome line. Conclusions/Significance: Pyrimidine salvage was not an essential function for bloodstream T. b. brucei. However, trypanosomes lacking de novo pyrimidine biosynthesis are completely dependent on an extracellular pyrimidine source, strongly preferring uracil, and display reduced infectivity. As T. brucei are able to salvage sufficient pyrimidines from the host environment, the py

African trypanosomes are capable of both pyrimidine biosynthesis and salvage of preformed pyrimidines from the host. However, uptake of pyrimidines in bloodstream form trypanosomes has not been investigated, making it difficult to judge the relative importance of salvage and synthesis or to design a pyrimidine-based chemotherapy. Detailed characterization of pyrimidine transport activities in bloodstream form Trypanosoma brucei brucei found that these cells express a high-affinity uracil transporter (designated TbU3) that is clearly distinct from the procyclic pyrimidine transporters. This transporter had low affinity for uridine and 2′deoxyuridine and was the sole pyrimidine transporter expressed in these cells. In addition, thymidine was taken up inefficiently through a P1-type nucleoside transporter. Of importance, the anticancer drug 5-fluorouracil was an excellent substrate for TbU3, and several 5-fluoropyrimidine analogs were investigated for uptake and trypanocidal activity; 5F-orotic acid, 5F-2′deoxyuridine displayed activity in the low micromolar range. The metabolism and mode of action of these analogs was determined using metabolomic assessments of T. brucei clonal lines adapted to high levels of these pyrimidine analogs, and of the sensitive parental strains. The analysis showed that 5-fluorouracil is incorporated into a large number of metabolites but likely exerts toxicity through incorporation into RNA. 5F-2′dUrd and 5F-2′dCtd are not incorporated into nucleic acids but act as prodrugs by inhibiting thymidylate synthase as 5F-dUMP. We present the most complete model of pyrimidine salvage in T. brucei to date, supported by genome-wide profiling of the predicted pyrimidine biosynthesis and conversion enzymes.

Given the pressing need for new antiprotozoal drugs without cross-resistance with current (failing) chemotherapy, we have explored 3-tridecylpyridinium alkaloids (3TPAs), derivatives of viscosamine, as antiparasitic agents. We have developed a simple synthetic route toward viscosamine and related cyclic and linear monomers and oligomers. Evaluation for cytotoxicity on the protozoan parasites Trypanosoma brucei, Leishmania spp., and Plasmodium falciparum revealed several 3TPAs with antiprotozoal activity in the nanomolar range. Their promising selectivity index in vitro prompted us to study the dynamics of cytotoxicity on trypanosomes in more detail. Parasites were killed relatively slowly at therapeutically safe concentrations, in a process that did not target the cell cycle. Clearance of T. brucei cultures was observed at drug concentrations of 1–10 μM.

The present study was performed to evaluate the anti-schistosomal activity of the medicinal plant ginger Zingiber officinale. Mice were individually infected with 100 Schistosoma mansoni cercariae. Four weeks post-infection, mice were orally treated with 1200 mg/kg of ginger for ten consecutive days. After the last dose all animals were sacrificed to evaluate the efficacy of ginger in treatment of the infection. The results obtained showed moderate reduction of 16.5% in the worm burden compared with control infected animals. The liver egg count showed a marked reduction of 53.8%. Ginger treatment showed a significant reduction in the size of liver granuloma where a percentage reduction of 66.35 was observed. Ginger treatment was slightly reflected on the liver function at such rate of infection, where an improvement in serum arginase activity was recorded, while no appreciable improvement in hepatic ALT and AST activities, albumin and creatinine contents. In conclusion Z. officinale displayed some degree of anti-schistosomal activity through reducing of the S. mansoni eggs output and the liver granuloma size.