Identification of Thioredoxin Glutathione Reductase Inhibitors That Kill Cestode and Trematode Parasites

Parasitic flatworms are responsible for serious infectious diseases that affect humans as well as livestock animals in vast regions of the world. Yet, the drug armamentarium available for treatment of these infections is limited: praziquantel is the single drug currently available for 200 million people infected with Schistosoma spp. and there is justified concern about emergence of drug resistance. Thioredoxin glutathione reductase (TGR) is an essential core enzyme for redox homeostasis in flatworm parasites. In this work, we searched for flatworm TGR inhibitors testing compounds belonging to various families known to inhibit thioredoxin reductase or TGR and also additional electrophilic compounds. Several furoxans and one thiadiazole potently inhibited TGRs from both classes of parasitic flatworms: cestoda (tapeworms) and trematoda (flukes), while several benzofuroxans and a quinoxaline moderately inhibited TGRs. Remarkably, five active compounds from diverse families possessed a phenylsulfonyl group, strongly suggesting that this moiety is a new pharmacophore. The most active inhibitors were further characterized and displayed slow and nearly irreversible binding to TGR. These compounds efficiently killed Echinococcus granulosus larval worms and Fasciola hepatica newly excysted juveniles in vitro at a 20 µM concentration. Our results support the concept that the redox metabolism of flatworm parasites is precarious and particularly susceptible to destabilization, show that furoxans can be used to target both flukes and tapeworms, and identified phenylsulfonyl as a new drug-hit moiety for both classes of flatworm parasites

Photography-based taxonomy is inadequate, unnecessary, and potentially harmful for biological sciences

The question whether taxonomic descriptions naming new animal species without type specimen(s) deposited in collections should be accepted for publication by scientific journals and allowed by the Code has already been discussed in Zootaxa (Dubois & Nemésio 2007; Donegan 2008, 2009; Nemésio 2009a–b; Dubois 2009; Gentile & Snell 2009; Minelli 2009; Cianferoni & Bartolozzi 2016; Amorim et al. 2016). This question was again raised in a letter supported by 35 signatories published in the journal Nature (Pape et al. 2016) on 15 September 2016. On 25 September 2016, the following rebuttal (strictly limited to 300 words as per the editorial rules of Nature) was submitted to Nature, which on 18 October 2016 refused to publish it. As we think this problem is a very important one for zoological taxonomy, this text is published here exactly as submitted to Nature, followed by the list of the 493 taxonomists and collection-based researchers who signed it in the short time span from 20 September to 6 October 2016

Nutrient removal using two species of mangrove (Rhizophora mangle and Laguncularia racemosa) in experimental shrimp (Litopenaeus vannamei) culture ponds

The nutrient removal capacity of two species of mangrove (Rhizophora mangle and Laguncularia racemosa) was assessed in shrimp (Litopenaeus vannamei) culture ponds. One pond contained R. mangle seedlings and another L. racemosa seedlings, while a tirad (control pond) was left without seedlings. Treatment ponds contained 20 floating platforms with 720 mangrove seedlings. Water was pumped from the estuary into the ponds. Nutrient (NO3 –, NO2 –, NH4 +, and PO4 –3) concentrations from the pond effluents were analyzed during the water exchange every 10 days. The results showed that L. racemosa removed 83.4% of dissolved inorganic nitrogen (DIN) and 45% of PO4 and R. mangle removed 79% of DIN and 40% of PO4, while 30% of DIN and 23% of PO4 was removed in the control pond. The flux of nutrients from the influent water to the ponds was 7269 g of N and 3095 g of P. In the ponds with mangroves, the nutrients were reduced to 1018–1071 g of N and 609–724 g of P. In the control pond, the effluent water nutrient concentrations were 5564 g of N and 1583 g of P. The nutrients accumulated in the mangrove tissue were 18,014–16,711 g of N and 5976–5832 g of P. Volatilization of ammonium and adsorption of phosphorus by sediments were 17,298–18,570 g of N and 6249–6268 g of P, and in the control pond, 30,022 g of N and 10,922 g of P, respectively. The final length for L. racemosa was 48 cm and the root length was 54 cm. For R. mangle, the final length was 38 cm and the root length was 46 cm. Shrimp survival was 70%, with individuals reaching 10.4 g in weight and 12.2 cm in length. We concluded that the nutrient removal percentage in ponds with mangrove seedlings was higher than in the pond without seedlings, improving water quality and reducing nutrients in the effluent

Ecological Niche Modelling of Endemic Fish Within La Paz Bay: Implications For Conservation

Endemic marine species are useful in determining and evaluating areas for conservation. Particularly Warm Temperate Province of the Northeast Pacific (WTPNP) includes priority conservation areas, but records of endemic marine species are limited, their distributions remains generally unknown, and often excluded in extant conservation plans. Within the WTPNP, the Balandra Protected Natural Area (BPNA) is located within La Paz Bay, and it is the only management area with a developed plan. However, marine endemic fish species have not been fully considering, and their protection status requires a re-evaluation, particularly the distribution of species with adequate spatial resolution. Despite the scarce information on marine endemic fishes, ecological niche modelling allows predicting distribution areas through occurrences of the species and their relationship with a set of scenopoetic environmental variables. The abiotically suitable areas based of the endemic marine fish species within the WTPNP documented within the Bay of La Paz were modeled and the high-value areas for conservation were established through a multi-species models; these spatial patterns of suitable areas were contrasted with the current state of fish protection. Modelling was performed with the Maxent software supplied with presence-only data of 18 species and four sets of environmental layers related to the geomorphology and bottom sedimentology, as well as the Euclidean distance measures from mangrove and rocky shore habitats. We generated sixteen distribution models that revealed that only 8.4 % of the predicted area, on average, was located within a maximum state of protection within the BPNA core zone. Moreover, the generated multi-species model reveals that only 17 % of the high-value areas (≥ 9 species/hectare) were located in the core zone. These high-value areas indicate updating the current management program is required. Finally, the study illustrates how the predicted-areas can be linked to conservation strategies in the marine habitat space within and outside the BPNA

Stratégie pour la Durabilité Environnementales du Milieu Côtier Transfrontalier

En prens

Erratum to: Guidelines for the use and interpretation of assays for monitoring autophagy (3rd edition) (Autophagy, 12, 1, 1-222, 10.1080/15548627.2015.1100356

non present