Site-specific recombinases, such as Cre, are a widely used tool for genetic lineage tracing in the fields of developmental biology, neural science, stem cell biology, and regenerative medicine. However, nonspecific cell labeling by some genetic Cre tools remains a technical limitation of this recombination system, which has resulted in data misinterpretation and led to many controversies in the scientific community. In the past decade, to enhance the specificity and precision of genetic targeting, researchers have used two or more orthogonal recombinases simultaneously for labeling cell lineages. Here, we review the history of cell-tracing strategies and then elaborate on the working principle and application of a recently developed dual genetic lineage-tracing approach for cell fate studies. We place an emphasis on discussing the technical strengths and caveats of different methods, with the goal to develop more specific and efficient tracing technologies for cell fate mapping. Our review also provides several examples for how to use different types of DNA recombinase–mediated lineage-tracing strategies to improve the resolution of the cell fate mapping in order to probe and explore cell fate–related biological phenomena in the life sciences.

Microscopy and rapid diagnostic tests (RDTs) are the main diagnostic tools for malaria but fail to detect low-density parasitemias that are important for maintaining malaria transmission. To complement existing diagnostic methods, an isothermal reverse transcription-recombinase polymerase amplification and lateral flow assay (RT-RPA) was developed. We compared the performance with that of ultrasensitive reverse transcription-quantitative PCR (uRT-qPCR) using nucleic acid extracts from blood samples (n = 114) obtained after standardized controlled human malaria infection (CHMI) with Plasmodium falciparum sporozoites. As a preliminary investigation, we also sampled asymptomatic individuals (n = 28) in an area of malaria endemicity (Lambaréné, Gabon) to validate RT-RPA and assess its performance with unprocessed blood samples (dbRT-RPA). In 114 samples analyzed from CHMI trials, the positive percent agreement to uRT-qPCR was 90% (95% confidence interval [CI], 80 to 96). The negative percent agreement was 100% (95% CI, 92 to 100). The lower limit of detection was 64 parasites/ml. In Gabon, RT-RPA was 100% accurate with asymptomatic volunteers (n = 28), while simplified dbRT-RPA showed 89% accuracy. In a subgroup analysis, RT-RPA detected 9/10 RT-qPCR-positive samples, while loop-mediated isothermal amplification (LAMP) detected 2/10. RT-RPA is a reliable diagnostic test for asymptomatic low-density infections. It is particularly useful in settings where uRT-qPCR is difficult to implement.

Background

Positive serology for cytomegalovirus (CMV) has been associated with all-cause mortality risk but its role in COPD mortality is unknown. The objective of the present study was to assess the relationship between CMV serology and COPD mortality.

For manufacturers of both sterile and nonsterile pharmaceuticals, there is an expectation that the manufacturing process is performed in a manner that prevents extraneous contamination so that the products are provided in a safe, integral, pure, and unadulterated form. As part of that process, cleaning and disinfection are an absolute necessity. Although cleaning and disinfection support control of microbial contamination through preventive and corrective action, specific compendia methods do not currently exist. The intent of this paper is to provide a general guidance on how to perform disinfectant efficacy validation and implementation. This includes how to make sure the concepts are understood, how to interpret facility data and utilize it to demonstrate control awareness for your facilities, and how to leverage the data to reduce redundancies in validation or verification. This paper represents the thoughts and best practices of the authoring team and their respective companies and provides an efficient way to qualify disinfectants without impacting the quality of the study. If you choose to follow the recommendations in this paper, you must ensure that the appropriate rationale is sound and the scientific data is documented. It is the belief of the authoring team that only then will this approach meet regulatory requirements.

An exceptionally well-preserved specimen of the articulated rhodophyte Permocalculus, compared with P. tenellus sensu Elliott, 1955, is described from fine-grained Upper Permian limestones of the Khuff Formation of Saudi Arabia. Longitudinal medullary and sheaf-like cortical filaments extend through the uniserial series of elongate-globular, concave- and convex-terminating, interlocking segments for which they are interpreted to have functioned in articulation. The filaments tend to splay and branch laterally into the cortex where they terminate at the pores. At the terminal aperture, the filaments extend as bifurcating and possibly trifurcating branches and may serve as the origin of a new segment. Numerous elongate-globular chambers, up to five in each row and intimately involved with the filaments, are developed in the outer medulla and are considered to represent reproductive sporangia. The specimen is considered to have occupied predominantly low-energy, normal to slightly elevated salinity, shallow conditions within the subtidal regime of a lagoon.

Approximately 40% of patients with diabetic macular edema (DME) are resistant to anti–vascular endothelial growth factor (VEGF) therapy (rDME). Here, we demonstrate that significant correlations between inflammatory cytokines and VEGF, as observed in naive DME, are lost in patients with rDME. VEGF overexpression in the mouse retina caused delayed inflammatory cytokine upregulation, monocyte/macrophage infiltration (CD11b⁺ Ly6C⁺ CCR2⁺ cells), macrophage/microglia activation (CD11b⁺ CD80⁺ cells), and blood-retinal barrier disruption due to claudin-5 redistribution, which did not recover with VEGF blockade alone. Phosphorylated protein analysis of VEGF-overexpressed retinas revealed rho-associated coiled-coil–containing protein kinase (ROCK) activation. Administration of ripasudil, a selective ROCK inhibitor, attenuated retinal inflammation and claudin-5 redistribution. Ripasudil also contributed to the stability of claudin-5 expression by both transcriptional enhancement and degradation suppression in inflammatory cytokine–stimulated endothelium. Notably, the anti-VEGF agent and the ROCK inhibitor were synergic in suppressing cytokine upregulation, monocyte/macrophage infiltration, macrophage/microglia activation, and claudin-5 redistribution. Furthermore, in vitro analysis confirmed that claudin-5 redistribution depends on ROCK2 but not on ROCK1. This synergistic effect was also confirmed in human rDME cases. Our results suggest that ROCK-mediated claudin-5 redistribution by inflammation is a key mechanism in the anti-VEGF resistance of DME.

Manoella Gemaque Cavalcante, Cleusa Yoshiko Nagamachi, Julio Cesar Pieczarka, and Renata Coelho Rodrigues Noronha

Eukaryotic genomes exhibit substantial accumulation of repetitive DNA sequences. These sequences can participate in chromosomal reorganization events and undergo molecular cooption to interfere with the function and evolution of genomes. In turtles, repetitive DNA sequences appear to be accumulated at probable break points and may participate in events such as non-homologous recombination and chromosomal rearrangements. In this study, repeated sequences of 5S rDNA, U2 snRNA and Tc1/Mariner transposons were amplified from the genomes of the turtles, Podocnemis expansa and Podocnemis unifilis, and mapped by fluorescence in situ hybridization. Our data confirm the 2n=28 chromosomes for these species (the second lowest 2n in the order Testudines). We observe high conservation of the co-located 5S rDNA and U2 snRNA genes on a small chromosome pair (pair 13), and surmise that this represents the ancestral condition. Our analysis reveals a wide distribution of the Tc1/Mariner transposons and we discuss how the mobility of these transposons can act on karyotypic reorganization events (contributing to the 2n decrease of those species). Our data add new information for the order Testudines and provide important insights into the dynamics and organization of these sequences in the chelonian genomes.

The identification of biomarkers for patient stratification is fundamental to precision medicine efforts in oncology. Here, we identified two baseline, circulating immune cell subsets associated with overall survival in patients with metastatic pancreatic cancer who were enrolled in two phase II randomized studies of GVAX pancreas and CRS-207 immunotherapy. Single-cell mass cytometry was used to simultaneously measure 38 cell surface or intracellular markers in peripheral blood mononuclear cells obtained from a phase IIa patient subcohort (N = 38). CITRUS, an algorithm for identification of stratifying subpopulations in multidimensional cytometry datasets, was used to identify single-cell signatures associated with clinical outcome. Patients with a higher abundance of CD8⁺CD45RO^–CCR7^–CD57⁺ cells and a lower abundance of CD14⁺CD33⁺CD85j⁺ cells had improved overall survival [median overall survival, range (days) 271, 43–1,247] compared with patients with a lower abundance of CD8⁺CD45RO^–CCR7^–CD57⁺ cells and higher abundance of CD14⁺CD33⁺CD85j⁺ cells (77, 24–1,247 days; P = 0.0442). The results from this prospective–retrospective biomarker analysis were validated by flow cytometry in 200 patients with pancreatic cancer enrolled in a phase IIb study (P = 0.0047). The identified immune correlates provide potential prognostic or predictive signatures that could be employed for patient stratification.

Background:

In Canada, First Nations populations experience a higher incidence of diabetes and diabetes-related complications than other people. Given the paucity of information on use of preventive eye examinations and the need for interventional care for severe retinopathy among First Nations people, we carried out a population-based study to compare rates of eye examinations and interventional therapies to treat vision-threatening stages of diabetic retinopathy among First Nations people and other people with diabetes in Ontario.

Dramatically rising costs in drug development are in large part because of the high failure rates in clinical phase trials. The poor correlation of animal studies to human toxicity and efficacy have led many developers to question the value of requiring animal studies in determining which drugs should enter in-human trials. Part 1 of this 2-part series examined some of the data regarding the lack of concordance between animal toxicity studies and human trials, as well as some of the potential reasons behind it. This second part of the series focuses on some alternatives to animal trials (hereafter referred to as animal research) as well as current regulatory discussions and developments regarding such alternatives.

Capsid assembly is a critical step in the hepatitis B virus (HBV) life cycle, mediated by the core protein. Core is a potential target for new antiviral therapies, the capsid assembly modulators (CAMs). JNJ-56136379 (JNJ-6379) is a novel and potent CAM currently in phase II trials. We evaluated the mechanisms of action (MOAs) and antiviral properties of JNJ-6379 in vitro. Size exclusion chromatography and electron microscopy studies demonstrated that JNJ-6379 induced the formation of morphologically intact viral capsids devoid of genomic material (primary MOA). JNJ-6379 accelerated the rate and extent of HBV capsid assembly in vitro. JNJ-6379 specifically and potently inhibited HBV replication; its median 50% effective concentration (EC₅₀) was 54 nM (HepG2.117 cells). In HBV-infected primary human hepatocytes (PHHs), JNJ-6379, when added with the viral inoculum, dose-dependently reduced extracellular HBV DNA levels (median EC₅₀ of 93 nM) and prevented covalently closed circular DNA (cccDNA) formation, leading to a dose-dependent reduction of intracellular HBV RNA levels (median EC₅₀ of 876 nM) and reduced antigen levels (secondary MOA). Adding JNJ-6379 to PHHs 4 or 5 days postinfection reduced extracellular HBV DNA and did not prevent cccDNA formation. Time-of-addition PHH studies revealed that JNJ-6379 most likely interfered with postentry processes. Collectively, these data demonstrate that JNJ-6379 has dual MOAs in the early and late steps of the HBV life cycle, which is different from the MOA of nucleos(t)ide analogues. JNJ-6379 is in development for chronic hepatitis B treatment and may translate into higher HBV functional cure rates.

Nosocomial pneumonia (NP), including ventilator-associated pneumonia (VAP), is increasingly associated with multidrug-resistant Gram-negative pathogens. This study describes the in vitro activity of ceftazidime-avibactam, ceftazidime, and relevant comparator agents against bacterial pathogens isolated from patients with NP, including VAP, enrolled in a ceftazidime-avibactam phase 3 trial. Gram-positive pathogens were included if coisolated with a Gram-negative pathogen. In vitro susceptibility was determined at a central laboratory using Clinical and Laboratory Standards Institute broth microdilution methods. Of 817 randomized patients, 457 (55.9%) had ≥1 Gram-negative bacterial pathogen(s) isolated at baseline, and 149 (18.2%) had ≥1 Gram-positive pathogen(s) coisolated. The most common isolated pathogens were Klebsiella pneumoniae (18.8%), Pseudomonas aeruginosa (15.8%), and Staphylococcus aureus (11.5%). Ceftazidime-avibactam was highly active in vitro against 370 isolates of Enterobacteriaceae, with 98.6% susceptible (MIC₉₀, 0.5 μg/ml) compared with 73.2% susceptible for ceftazidime (MIC₉₀, >64 μg/ml). The percent susceptibility values for ceftazidime-avibactam and ceftazidime against 129 P. aeruginosa isolates were 88.4% and 72.9% (MIC₉₀ values of 16 μg/ml and 64 μg/ml), respectively. Among ceftazidime-nonsusceptible Gram-negative isolates, ceftazidime-avibactam percent susceptibility values were 94.9% for 99 Enterobacteriaceae and 60.0% for 35 P. aeruginosa. MIC₉₀ values for linezolid and vancomycin (permitted per protocol for Gram-positive coverage) were within their respective MIC susceptibility breakpoints against the Gram-positive pathogens isolated. This analysis demonstrates that ceftazidime-avibactam was active in vitro against the majority of Enterobacteriaceae and P. aeruginosa isolates from patients with NP, including VAP, in a phase 3 trial. (This study has been registered at ClinicalTrials.gov under identifier NCT01808092.)

Background:

The impact of light-intensity physical activity (LPA) in preventing cancer mortality has been questioned. To address this concern, the present meta-analysis aimed to quantify the association between objectively-measured LPA and risk of cancer mortality.

Ovarian cancer imposes a substantial health and economic burden. We systematically reviewed current health-economic evidence for ovarian cancer early detection or prevention strategies. Accordingly, we searched relevant databases for cost-effectiveness studies evaluating ovarian cancer early detection or prevention strategies. Study characteristics and results including quality-adjusted life years (QALY), and incremental cost-effectiveness ratios (ICER) were summarized in standardized evidence tables. Economic results were transformed into 2017 Euros. The included studies (N = 33) evaluated ovarian cancer screening, risk-reducing interventions in women with heterogeneous cancer risks and genetic testing followed by risk-reducing interventions for mutation carriers. Multimodal screening with a risk-adjusted algorithm in postmenopausal women achieved ICERs of 9,800–81,400 Euros/QALY, depending on assumptions on mortality data extrapolation, costs, test performance, and screening frequency. Cost-effectiveness of risk-reducing surgery in mutation carriers ranged from cost-saving to 59,000 Euros/QALY. Genetic testing plus risk-reducing interventions for mutation carriers ranged from cost-saving to 54,000 Euros/QALY in women at increased mutation risk. Our findings suggest that preventive surgery and genetic testing plus preventive surgery in women at high risk for ovarian cancer can be considered effective and cost-effective. In postmenopausal women from the general population, multimodal screening using a risk-adjusted algorithm may be cost-effective.

Twitch is doubling down on esports in this new era of social distancing as a number of traditional sporting events have been cancelled. The company this week introduced a new esports directory on its site that will make it easier for viewers to find live matches, information on players, games with active competition leagues, a […]

Modern Games is a new studio working to create games that combine physical and digital play. The company was founded by husband-and-wife team Justin and Amanda Kifer — serial entrepreneurs who previously launched companies including Citizen Local (acquired by MyLife in 2011) and Fidgetly, a fidget spinner company that also created a motion controller for […]

Alec Baldwin also returned to the 'SNL' stage as Donald Trump in the cold open.

As a biological anthropologist focused on health, diseases are part of Sabrina Sholts' specialty

Surface Book 3 gets more RAM, Surface Go 2 gets a bigger display, and more.

A total of 26,097 people have died in hospitals, care homes and the wider community after testing positive for coronavirus, Public Health England has said.

"Deepfakes" have received a lot of attention as a way to potentially spread misleading or false information and influence public opinion. But two specialists say that might not be a huge concern.

On Monday, officials in Los Angeles County released preliminary results of a study that suggest roughly 4.1% of the county's adult population has already had the coronavirus, which translates to between 221,000 and 442,000 people, factoring in adjustments for statistical margin of error.That's a much higher number than confirmed case counts indicate. (As of early Tuesday, the county had 13,816 cases.)"We haven't known the true extent of COVID-19 infections in our community because we have only tested people with symptoms and the availability of tests has been limited," Neeraj Sood, a professor of public policy at the University of Southern California and lead investigator on the study, said in a statement.Dr. Barbara Ferrer, LA County's public health director, said in a statement that the early results pointed to the possibility that many people may have been unknowingly infected.The study relies on rapid antibody tests, which have faced concerns about accuracy.And as The Mercury News reported, a Stanford study that also showed higher rates of infection in Santa Clara County drew criticism, although that was largely from statisticians over the study's methodology.Still, experts have emphasized that more studies will help develop a clearer picture of the virus's true prevalence.In any case, officials say it's crucial to continue to adhere to public health orders for many reasons, including that if more people are infected but asymptomatic, they could unknowingly spread the virus.______A change to the USNS Mercy's assignmentOn Monday, my New York Times colleague John Ismay and I spoke with leaders aboard the Navy hospital ship Mercy. Here's our dispatch about how their assignment has changed:In the weeks since the Mercy arrived at the Port of Los Angeles from San Diego, the hospital ship's mission has been clear: Serve as a crucial relief valve for patients who have not been infected with the coronavirus as hospitals fill up with patients sick with COVID-19.In recent days, the work has shifted, but that underlying goal has remained the same, the commanding officer of the ship's medical facility told us."FEMA, after having made an assessment of the situation and the local needs, has changed our assignment," said Capt. John Rotruck, the medical treatment team's commanding officer.The Mercy has sent 40 medical staff members -- two family practice doctors, 16 nurses and 20 corpsmen, including two respiratory technicians -- to help care for patients who do not have COVID-19 at a state-run skilled nursing facility in Orange County."We're essentially augmenting their staff," Rotruck said, as the anticipated surge in COVID-19 hospitalizations has, for now, been held at bay.The capacity onboard will decrease to 250 beds from 1,000, in large part as a result of that staffing shift -- although officials emphasized that leaves more than enough space at the rate the Mercy has been taking in patients.At the same time, leaders aboard the Mercy said that most of the military crew is moving off the ship to stay at nearby hotels to make it possible for crew members to keep their distance from one another as they work, eat and sleep.Sailors will be bused from their hotels to work their shifts aboard the ship.The move, which will decrease the number of crew members staying aboard the ship to roughly 140 from more than 800, came as the number of crew members who may have been exposed inched upward.By Monday, Rotruck said that nine crew members had tested positive for the coronavirus and that about 130 people were in quarantine because they had come into what federal officials define as close contact with at least one of those nine. All of those in quarantine tested negative.All nine who have COVID-19 were outpatients as of Monday -- meaning their cases were not severe enough to warrant being hospitalized -- and their conditions are being closely monitored.Rotruck said that moving crew members off the Mercy was unusual but not unprecedented.During a previous mission, for instance, some medical staff members flew to Vietnam to provide medical care to patients on the Mercy, although they did not sleep on the ship.However, Rotruck added, "We have not done it to this scale," with the vast majority of the ship's crew members living ashore.A spokesman said Friday that the crew aboard the Navy hospital ship Comfort, which is docked in New York City, recently moved most of its crew to hotels ashore as well.Rotruck said that the Mercy was ready to care for coronavirus-negative seniors living in nursing homes, as the governor has previously announced, but none had been transferred yet.Such nursing home patients may be moved to the Mercy for care through the typical intake process, if, for example, a facility needed to free up space to care for COVID-19 patients.As of Monday evening, the ship had taken in 65 patients total since it docked in San Pedro, and its crew had performed 22 surgeries. There were 13 patients still being treated onboard, meaning that 52 had been discharged.This article originally appeared in The New York Times.(C) 2020 The New York Times Company

One month after the debut of the COVID-19 Open Research Dataset, or CORD-19, the database of coronavirus-related research papers has doubled in size – and has given rise to more than a dozen software tools to channel the hundreds of studies that are being published every day about the pandemic. In a roundup published on the ArXiv preprint server this week, researchers from Seattle's Allen Institute for Artificial Intelligence, Microsoft Research and other partners in the project say CORD-19's collection has risen from about 28,000 papers to more than 52,000. Every day, several hundred more papers are being published, in… Read More

Australian scientists also working to evaluate extent of immunity to virus among public

'We propose that Sars-Cov-2 may have the potential to be transmitted via aerosols,' researchers say

PM Studios online store is back and they made a new sale featuring new reprints, overall deals and restock on rare out-of-print titles from Limited Run Games.

https://twitter.com/PMStudiosUSA/status/1253401043414781959

Also all orders over $49.99 will get Cytus Alpha Limited Edition Original Soundtrack CD for free with the Coupon "FREEGIFT".

Kinda sick move they did now.

https://www.pm-studios.com/store

Edit: Price list.