Targeting malaria virulence and remodeling proteins to the host erythrocyte

To establish infection in the host, malaria parasites export remodeling and virulence proteins into the erythrocyte. These proteins can traverse a series of membranes, including the parasite membrane, the parasitophorous vacuole membrane, and the erythrocyte membrane. We show that a conserved pentameric sequence plays a central role in protein export into the host cell and predict the exported proteome in Plasmodium falciparum. We identified 400 putative erythrocyte-targeted proteins corresponding to approximately 8% of all predicted genes, with 225 virulence proteins and a further 160 proteins likely to be involved in remodeling of the host erythrocyte. The conservation of this signal across Plasmodium species has implications for the development of new antimalarials.     

大型底栖动物入侵种:它们是否对德国水生动物群落构成威胁?

在水体中发现大型底栖动物入侵种是一种世界范围普遍的现象。人类移动的同时将物品从一个大陆带到另一个大陆,这使许多水生动物物种能够突破自然的防线侵入到其他的区域和大陆。藉由人类现代的旅行方式,在不同区域间移动的物种数量显著增加,成功入侵种的数量也随之增多。成功入侵种需要具备一些特征,如可动性,小体型,适应性强和繁殖率高等,这些均有利于物种跨区域的入侵。当然,新生活环境也必须满足可适应的标准。对一个受人类活动破坏而丧失其原有物种的水环境来说,它对新物种入侵的抵抗力会很弱甚至缺乏。德国水体受人类活动的胁迫非常严重,许多自然水体受到的破坏已无法挽回,有些甚至已经完全成为了人工环境。这些水体由相互连接着的溪流河川网络组成,这很容易使新物种的入侵范围扩大。在外来物种的入侵面前,受人类活动胁迫和直接破坏的水体,比尚保持着天然环境状况的水体更加脆弱。     

Primary bone marrow T‐cell lymphoma in a Golden Retriever

A 6.2‐year‐old 28‐kg (61.7 lb) intact female Golden Retriever was referred due to persistent and multiple cytopenias noted on a routine CBC prior to a mature ovariohysterectomy procedure. The patient's physical examination was unremarkable, and staging of the thorax and abdomen identified no abnormalities. At the referral hospital, moderate hypercalcemia, borderline anemia, and neutropenia were noted. Assessment of bone marrow samples by cytology, histology, immunohistochemistry, and flow cytometry indicated a T‐cell neoplasm. The patient was treated with a multi‐agent chemotherapy protocol for 6 months, which induced remission. Nine months after diagnosis, she relapsed with recurrence of hypercalcemia, cytopenias, and clinical illness. Single‐agent anthracycline (mitoxantrone) in combination with prednisone therapy was initiated for 3 months. Two months after completion, the patient relapsed again, and palliative therapy with prednisone was elected. The patient was euthanized 16 months after diagnosis due to progressive disease. Post‐mortem histopathologic evaluation showed extensive replacement of bone marrow by neoplastic cells, and infiltrates in multiple organs. The neoplasm was diagnosed as lymphoma rather than leukemia due to the lack of abnormal circulating cells throughout the course of disease. The neoplasm was detected only in marrow at the time of initial diagnosis, and the marrow was the most extensively effaced organ at the time of death. Therefore, leukemia or stage V lymphoma was considered unlikely. In patients with a cytopenia and lack of neoplastic leukocytosis or solid tissue masses, primary bone marrow lymphoma should be considered among the differential diagnoses.     

Pyogranulomatous panniculitis in a domestic cat associated with Pseudomonas luteola infection

Pseudomonas luteola, a pathogen causing disease in humans, has in animals been reported only in rainbow trout and ferrets. This case report describes pyogranulomatous panniculitis in a cat associated with P. luteola infection. Organisms were seen histologically and identified with PCR and sequencing. Lesions resolved after treatment with marbofloxacin.     

Next-generation sequencing capacity and capabilities within the National Animal Health Laboratory Network

With the cost of next-generation sequencing (NGS) decreasing, this technology is rapidly being integrated into the workflows of veterinary clinical and diagnostic laboratories nationwide. The mission of the U.S. Department of Agriculture–National Animal Health Laboratory Network (NAHLN) is in part to evaluate new technologies and develop standardized processes for deploying these technologies to network laboratories for improving detection and response to emerging and foreign animal diseases. Thus, in 2018, the NAHLN identified the integration of NGS into the network as a top priority. In order to assess the current state of preparedness across NAHLN laboratories and to identify which have the capability for performing NGS, a questionnaire was developed by the NAHLN Methods Technical Working Group and submitted to all NAHLN laboratories in December 2018. Thirty of 59 laboratories completed the questionnaire, of which 18 (60%) reported having some sequencing capability. Multiple sequencing platforms and reagents were identified, and limited standardized quality control parameters were reported. Our results confirm that NGS capacity is available within the NAHLN, but several gaps remain. Gaps include not having sufficient personnel trained in bioinformatics and data interpretation, lack of standardized methods and equipment, and maintenance of sufficient computing capacity to meet the growing demand for this technology.     

Historical rates of atmospheric Pb deposition using210Pb dated peat cores: Corroboration,computation, and interpretation

Lead-210 dating of peat cores is one approach that has been used to arrive at historical rates of heavy metal deposition. Despite concerns regarding the validity of²¹⁰Pb dating due to Pb mobility,²¹⁰Pb dating can be used if the dates are corroborated with some other independent dating technique. In this study, based on analyses of²¹⁰Pb dated, pollen corroborated peat cores from two sites in the Czech Republic (Jezerní sla and Bo?í Dar Bog), we illustrate a previously unexplored problem concerning the computation of metal deposition, using Pb as an example. When peat cores are collected, sectioned into depth intervals,²¹⁰Pb dated and analyzed for metal contents, the²¹⁰Pb dates most appropriately correspond to the midpoint depth for each interval, whereas the metal contents correspond to the interval between the top and bottom of each section. Thus the²¹⁰Pb dates and metal content values throughout the core are offset by half the distance of each depth interval. In calculating historical rates of heavy metal deposition two approaches are available for correcting for the depth interval offsets, the traditional approach of date interpolation and our newly proposed metal content interpolation. We see noa priori reason for choosing one approach over the other, and suggest simultaneous use of both date and metal content interpolation. Additionally, acid-insoluble ash (AIA), which has been proposed as a dating technique in and of itself, may be more useful as an interpretive tool which may provide insights into the nature or sources of atmospherically deposited Pb. For example, plots of Pb content per core section versus AIA content per core section for Jezerní slat, located in a relatively pristine area, reveal increased Pb content without increased AIA contents in depths shallower than 6 cm, indicating deposition of gasoline-derived Pb after its introduction in 1922. Similar plots for Bo?í Dar Bog, located in a polluted industrialized region, indicate greater inputs of Pb than would be predicted from AIA, based on the Jezerní sla analyses. We interpret the apparent excess Pb deposition at Bo?í Dar Bog as being contributed by soil-derived dust from local metal mining. Elevated rates in Pb deposition at Bo?í Dar Bog are consistent with the history of local mining known to have occurred in the vicinity. Finally, magnetic susceptibility measurements identify combustion of fossil fuels as a source of atmospheric Pb deposition at Bo?í Dar Bog, but not at Jezerní sla      

The influence of mycorrhizal associations on paper birch and jack pine seedlings when exposed to elevated copper,nickel or aluminum

Acid deposition may adversely affect northern forest ecosystems by increasing the concentration of metals in the soil solution. This study investigates the effects of ectomycorrhizal fungi on paper birch and jack pine seedlings exposed to elevated Cu, Ni, or Al in sand culture. One of four mycorrhizal fungi,Scleroderma flavidum, was able to reduce Ni toxicity to the birch seedlings. It did this by reducing transport of Ni to the stems. None of the fungi affected Cu toxicity in birch. In separate experiments, jack pine seedlings were exposed to combinations of Al and Ca. Infection withRhizopogon rubescens increased seedling susceptibility to A1. Seedlings inoculated withSuillus tomentosus showed a greater growth stimulation by Ca than uninoculated jack pines. Thus, for both tree species, the mycorrhizal association could alter the response of seedlings to high concentrations of certain metals, although this varied with fungal species.     

Simple sequence repeat markers for botanical varieties of cultivated peanut (Arachis hypogaea L.)

Cultivated peanut (Arachis hypogaea L.) consists of six botanical varieties. Identification of DNA markers associated with botanical varieties would be useful in plant genotyping, germplasm management, and evolutionary studies. We have developed 130 simple sequence repeat (SSR) markers in peanut, 38 of which were used in this study because of their ability in detecting genetic polymorphism among 24 peanut accessions. Eight SSR markers were found useful to classify botanical varieties. Among them, six SSR markers were specific to botanical varieties fastigiata and vulgaris, one to botanical varieties hypogaea and hirsuta, and one to botanical varieties peruviana, and aequatoriana. Also, three of them derived from peanut expressed sequence tags (ESTs) were associated with putative genes. As botanical varieties have different morphological traits and belong to different subspecies in A. hypogaea, these markers might be associated with genes involved in the expression of morphological traits. The results also suggested that SSRs (also called microsatellites) might play a role in shaping evolution of cultivated peanut. Multiplex PCR of botanical variety-specific markers could be applied to facilitate efficient genotyping of the peanut lines.