Analysis of P-Loop and its Flanking Region Subsequence of Diverse NTPases Reveals Evolutionary Selected Residues

The P-loop NTPases are involved in diverse cellular functions. Members of the P-loop NTPase superfamily are characterized by presence of a highly conserved sequence pattern GxxxxGKS/T, known as Walker A motif. This motif adopts an archetypal P-loop conformation which allows accommodation of the triphosphate moiety of a bound nucleotide. Despite the presence of Walker A as a common sequence motif, P-loop NTPases exhibit extreme sequence divergence which hampers their phylogenetic or evolutionary classification. Here, we show that P-loop and its flanking region subsequence (termed as “extended-WalkerA motif”) contain distinct signatures that can be utilized to classify NTPase domain of functionally diverse proteins. We find a clearly classified group of diverse NTPases of Conserved Domain Database such as G-proteins, Ylqf, RecA like, DExDc, AAA, CPT, NK, ABC transporter and NifH proteins.     

Male age affects female mating preference but not fitness in the monandrous moth Dendrolimus punctatus Walker (Lepidoptera: Lasiocampidae)

It is widely accepted that male age can influence female mating preference and subsequent fitness consequences in many polyandrous species, yet this is seldom investigated in monandrous species. In the present study, we use the monandrous pine moth Dendrolimus punctatus to examine the effects of male age on female mating preference and future reproductive potential. In multiple male trials, when permitted free mating from an aggregation consisting of virgin males aged 0 (young), 2 (middle-aged) and 4 (old) days, virgin females preferentially mate with young and middle-aged males, although mating latency and mating duration are independent of male age. In single male trials, when virgin females are randomly assigned single virgin males of known age, a negative correlation is found between mating success and male age in this species. However, we find that male age also has no effect on mating latency and mating duration. Further fitness analysis reveals that females do not receive benefits in terms of oviposition period, total egg production, average daily egg production, percentage of egg hatching, longevity, expected reproduction and relative expected reproduction from mating with young and middle-aged males compared with mating with old males. The results of the present study are the first demonstrate that females mated preferentially with younger males but gain no apparent fitness benefits in a monandrous moth species.     

A comparative study of the bactericidal activity of horseshoe crab (Limulus polyphemus) hemolymph and vertebrate serum

This paper describes a partially heat-labile, naturally occurring bactericidal factor in cell-free hemolymph preparations obtained from Limulus polyphemus. This bactericidal activity has been shown to be directed against two Gram-negative bacteria, Escherichia coli and Klebsiella pneumoniae, whereas it had no effect on the Gram-positive bacteria tested, Micrococcus lysodeikticus and Staphylococcus aureus. Maximal bactericidal activity of this factor was observed at 30°C and pH 6.0. Since complement and antibody are required for antimicrobial activity in vertebrate sera, the activity of this factor in the presence of various complement inhibitors was assayed. The bactericidal activity of Limulus hemolymph is abolished by treatment with endotoxin; however, other anticomplementary substances were without effect. Limulus amebocyte lysate is known to contain protein which may be precipitated by endotoxin; it is possible that the reduction of bactericidal activity produced by endotoxin treatment may be caused by the denaturation of a bactericidal protein moiety produced by the hemocytes.     

NTPDase and 5′ ecto-nucleotidase expression profiles and the pattern of extracellular ATP metabolism in the Walker 256 tumor

In this study, we evaluated the NTPDases and ecto-5′-nucleotidase (CD73) expression profiles and the pattern of adenine nucleotide hydrolysis in rats submitted to the Walker 256 tumor model, 6, 10 and 15 days after the subcutaneous inoculation. Using RT-PCR analysis, we identified mRNA for all of the members of the ecto-nucleoside triphosphate diphosphohydrolase family investigated and a 5′-nucleotidase. By quantitative real-time PCR, Entpd1 (Cd39) and Entpd2 (Cd39L1) and CD73 were identified as the dominant genes expressed by the Walker 256 tumor, at all times studied. Extracellular adenine nucleotide hydrolysis by the Walker 256 tumor was estimated by HPLC analysis. Rapid hydrolysis of extracellular ATP by the tumor cells was observed, leading to the formation of adenosine and inosine in cells obtained from solid tumors at 6 and 10 days after inoculation. Cells obtained from solid tumors at 15 days of growth presented high levels of AMP and presented adenosine as a final product after 90 min of incubation. Results demonstrate that the presence of NTPDases and 5′-nucleotidase enzymes in Walker 256 tumor cells may be important for regulation of the extracellular adenine nucleotides/adenine nucleoside ratio, therefore leading to tumor growth.     

Monitoring <i>Thosea sinensis</i> Walker in Tea Plantations Based on UAV Multi-Spectral Image

Thosea sinensis Walker (TSW) rapidly spreads and severely damages the tea plants. Therefore, finding a reliable operational method for identifying the TSW-damaged areas via remote sensing has been a focus of a research community. Such methods also enable us to calculate the precise application of pesticides and prevent the subsequent spread of the pests. In this work, based on the unmanned aerial vehicle (UAV) platform, five band images of multispectral red-edge camera were obtained and used for monitoring the TSW in tea plantations. By combining the minimum redundancy maximum relevance (mRMR) with the selected spectral features, a comprehensive spectral selection strategy was proposed. Then, based on the selected spectral features, three classic machine learning algorithms, including random forest (RF), support vector machine (SVM), and k-nearest neighbors (KNN) were used to construct the pest monitoring model and were evaluated and compared. The results showed that the strategy proposed in this work obtained ideal monitoring accuracy by only using the combination of a few optimized features (2 or 4). In order to differentiate the healthy and TSW-damaged areas (2-class model), the monitoring accuracies of all the three models were computed, which were above 96%. The RF model used the least number of features, including only SAVI and Band_red. In order to further discriminate the pest incidence levels (3-class model), the monitoring accuracies of all the three models were computed, which were above 80%, among which the RF algorithm based on SAVI, Band_red, VARI_green, and Band_{red_edge} features achieve the highest accuracy (OAA of 87%, and Kappa of 0.79). Considering the computational cost and model accuracy, this work recommends the RF model based on a few optimal feature combinations to monitor and distinguish the severity of TSW in tea plantations. According to the UAV remote sensing mapping results, the TSW infestation exhibited an aggregated distribution pattern. The spatial information of occurrence and severity can offer effective guidance for precise control of the pest. In addition, the relevant methods provide a reference for monitoring other leaf-eating pests, effectively improving the management level of plant protection in tea plantations, and guaranting the yield and quality of tea plantations.     

Anticarcinogenic Reactivity of Copper-Dischiffbases with Superoxide Dismutase-Like Activity

CuPu(Py)₂ and CuPu(Im)₂, two novel dischiffbase coordinated low Mr active centre analogues of Cu_{2, Zn2} superoxide dismutase, were shown to effectively catalyze the production of hydroxyl radicals in the presence and absence of TPA activated polymorphonuclear leukocytes. These stable copper chelates exhibited a pronounced anticarcinogenic reactivity in male Sprague Dawley rats implanted with Walker 256 carcinosarcoma cells. When four doses of 5°mol/kg CuPu(Py)₂ and CuPu(Im)₂, respectively, were administered intratumorally, reduction in tumor size, delay of metastasis and a significant increase in survival of the hosts were observed, resulting in 75% of total remissions. 60% of the animals recovered totally from the carcinosarcoma, when CuPu(Py)₂ was applicated intravenously.     

Dandy�CWalker malformation: An incidental finding

Dandy–Walker malformation (DWM) is a rare intracranial congenital abnormality that affects the cerebellum and some of its components; particularly cerebellar vermis, fourth ventricle and is characterized by an enlarged posterior fossa. Although there is an extensive list of signs attributed to DWM, final diagnosis is solely dependent on imaging techniques as there are no signs that are characteristic of DWM. This article reports a case with DWM who was diagnosed by magnetic resonance imaging.