Citizen science and online data: Opportunities and challenges for snake ecology and action against snakebite

The secretive behavior and life history of snakes makes studying their biology, distribution, and the epidemiology of venomous snakebite challenging. One of the most useful, most versatile, and easiest to collect types of biological data are photographs, particularly those that are connected with geographic location and date-time metadata. Photos verify occurrence records, provide data on phenotypes and ecology, and are often used to illustrate new species descriptions, field guides and identification keys, as well as in training humans and computer vision algorithms to identify snakes. We scoured eleven online and two offline sources of snake photos in an attempt to collect as many photos of as many snake species as possible, and attempt to explain some of the inter-species variation in photograph quantity among global regions and taxonomic groups, and with regard to medical importance, human population density, and range size. We collected a total of 725,565 photos—between 1 and 48,696 photos of 3098 of the world's 3879 snake species (79.9%), leaving 781 “most wanted” species with no photos (20.1% of all currently-described species as of the December 2020 release of The Reptile Database). We provide a list of most wanted species sortable by family, continent, authority, and medical importance, and encourage snake photographers worldwide to submit photos and associated metadata, particularly of “missing” species, to the most permanent and useful online archives: The Reptile Database, iNaturalist, and HerpMapper.ISSN:2590-171

Assessment of acute myocardial infarction: current status and recommendations from the North American society for cardiovascular imaging and the European society of cardiac radiology

There are a number of imaging tests that are used in the setting of acute myocardial infarction and acute coronary syndrome. Each has their strengths and limitations. Experts from the European Society of Cardiac Radiology and the North American Society for Cardiovascular Imaging together with other prominent imagers reviewed the literature. It is clear that there is a definite role for imaging in these patients. While comparative accuracy, convenience and cost have largely guided test decisions in the past, the introduction of newer tests is being held to a higher standard which compares patient outcomes. Multicenter randomized comparative effectiveness trials with outcome measures are required

Finishing the euchromatic sequence of the human genome

The sequence of the human genome encodes the genetic instructions for human physiology, as well as rich information about human evolution. In 2001, the International Human Genome Sequencing Consortium reported a draft sequence of the euchromatic portion of the human genome. Since then, the international collaboration has worked to convert this draft into a genome sequence with high accuracy and nearly complete coverage. Here, we report the result of this finishing process. The current genome sequence (Build 35) contains 2.85 billion nucleotides interrupted by only 341 gaps. It covers ∼99% of the euchromatic genome and is accurate to an error rate of ∼1 event per 100,000 bases. Many of the remaining euchromatic gaps are associated with segmental duplications and will require focused work with new methods. The near-complete sequence, the first for a vertebrate, greatly improves the precision of biological analyses of the human genome including studies of gene number, birth and death. Notably, the human enome seems to encode only 20,000-25,000 protein-coding genes. The genome sequence reported here should serve as a firm foundation for biomedical research in the decades ahead

Proportions and Serogroups of Enterohemorrhagic Shiga Toxin-producing Escherichia coli in Feces of Fed and Cull Beef and Cull Dairy Cattle at Harvest

Cattle are considered a primary reservoir of Shiga toxin (stx)-producing Escherichia coli that cause enterohemorrhagic disease (EHEC), and contaminated beef products are one vehicle of transmission to humans. However, animals entering the beef harvest process originate from differing production systems: feedlots, dairies, and beef breeding herds. The objective of this study was to determine if fed cattle, cull dairy, and or cull beef cattle carry differing proportions and serogroups of EHEC at harvest. Feces were collected via rectoanal mucosal swabs (RAMSs) from 1,039 fed cattle, 1,058 cull dairy cattle, and 1,018 cull beef cattle at harvest plants in seven U.S. states (CA, GA, NE, PA, TX, WA, and WI). The proportion of the stx gene in feces of fed cattle (99.04%) was not significantly different (P > 0.05) than in the feces of cull dairy (92.06%) and cull beef (91.85%) cattle. When two additional factors predictive of EHEC (intimin and ecf1 genes) were considered, EHEC was significantly greater (P < 0.05) in fed cattle (77.29%) than in cull dairy (47.54%) and cull beef (38.51%) cattle. The presence of E. coli O157:H7 and five common non-O157 EHEC of serogroups O26, O103, O111, O121, and O145 was determined using molecular analysis for single nucleotide polymorphisms (SNPs) followed by culture isolation. SNP analysis identified 23.48%, 17.67%, and 10.81% and culture isolation confirmed 2.98%, 3.31%, and 3.00% of fed, cull dairy, and cull beef cattle feces to contain one of these EHEC, respectively. The most common serogroups confirmed by culture isolation were O157, O103, and O26. Potential EHEC of fourteen other serogroups were isolated as well, from 4.86%, 2.46%, and 2.01% of fed, cull dairy, and cull beef cattle feces, respectively; with the most common being serogroups O177, O74, O98, and O84. The identification of particular EHEC serogroups in different types of cattle at harvest may offer opportunities to improve food safety risk management

The Ctf18RFC Clamp Loader Is Essential for Telomere Stability in Telomerase-Negative and <i>mre11</i> Mutant Alleles

<div><p>The function of the replication clamp loaders in the semi-conservative telomere replication and their relationship to telomerase- and recombination mechanisms of telomere addition remains ambiguous. We have investigated the variant clamp loader Ctf18 RFC (Replication Factor C). To understand the role of Ctf18 at the telomere, we first investigated genetic interactions after loss of Ctf18 and TLC1 (the yeast telomerase RNA). We find that the <i>tlc1▵ ctf18▵</i> double mutant confers a rapid >1000-fold decrease in viability. The rate of loss was similar to the kinetics of cell death in <i>rad52▵ tlc1▵</i> cells. However, the Ctf18 pathway is distinct from Rad52, required for the repair of DSBs, as demonstrated by the synthetic lethality of <i>rad52▵ tlc1▵ ctf18▵</i> triple mutants. These data suggest that each mutant elicits non-redundant defects acting on the same substrate. Second, interactions of the yeast hyper-recombinational mutant, <i>mre11A470T, with ctf18▵</i> confer a synergistic cold sensitivity. The phenotype of these double mutants ultimately results in telomere loss and the generation of recombinational survivors. We observed a similar synergism between single mutants that led to hypersensitivity to the DNA alkylating agent, methane methyl sulphonate (MMS), the replication fork inhibitor hydroxyurea (HU), and to a failure to separate telomeres of sister chromatids. Hence, <i>ctf18▵</i> and <i>mre11A470T</i> act in different pathways on telomere substrates for multiple phenotypes. The <i>mre11A470T</i> cells also displayed a DNA damage response (DDR) at 15°C but not at 30°C while <i>ctf18▵</i> mutants conferred a constitutive DDR activity. Both the 15°C DDR pattern and growth rate were reversible at 30°C and displayed telomerase activity <i>in vivo</i>. We hypothesize that Ctf18 confers protection against stalling and/or breaks at the replication fork in cells that either lack, or are compromised for, telomerase activity. This Ctf18-based function is likely to contribute another level to telomere size homeostasis.</p></div

Western blot analysis of DNA damage responses to <i>mre11A470T</i> and <i>ctf18</i>▵ Mutations.

<p>[<b>Top</b>]: Protein extracts were isolated from wild-type, <i>mre11A470T</i>, <i>ctf18▵</i> and <i>mre11A470T ctf18▵</i> cultures grown in 5 ml YPD cultures at 30°C or 15°C. Extracts were subjected to electrophoresis on a 10% SDS-PAGE gel prior to Western analysis using goat primary polyclonal anti-Rad53 antibody as described in Materials and Methods. Phosphorylated forms (arrows on right) migrate more slowly than the un-phosphorylated species. [<b>Bottom</b>]: Protein extracts were isolated from cold resistant <i>mre11A470T ctf18Δ</i> survivors and grown in 5 ml YPD at 15°C before shifting to 30°C. Extracts were subjected to Western analysis for Rad53 expression as described above.</p

<i>mre11A470T ctf18</i>▵ cold sensitive survivors arise via recombinational mechanisms.

<p>[<b>GT</b>] DNA isolated from the indicated strains (top) grown at 30°C and 15°C and from ten independent survivors (1–10) were digested with XhoI and Southern analysis performed using poly GT as a telomeric probe. Arrow on right indicates position of Type I survivor. Note that the smearing of the distribution that represents the distribution of Type II-like survivors. [<b>PEP4</b>] Southern blot from above was stripped and probed with <i>PEP4</i> sequences as an internal loading control.</p

<i>mre11A470T pol32 Δ</i> is cold sensitive for growth.

<p>Ten microliters of wild type, <i>mre11A470T</i>, <i>pol32▵</i> and <i>mre11A470T pol32▵</i> cultures grown at 30°C were spotted onto YPD plates at 10-fold serial dilutions [arrow above] and incubated at either 30°C [left] for two days or at 15°C [right] for five days of growth.</p