Cytoplasmic localization of calcium/calmodulin-dependent protein kinase I-α depends on a nuclear export signal in its regulatory domain

AbstractCalcium/calmodulin-dependent protein kinase I-α (CaMKI-α) is a ubiquitous cytosolic enzyme that phosphorylates a number of nuclear proteins in vitro and has been implicated in transcriptional regulation. We report that cytoplasmic localization of CaMKI-α depends on CRM1-mediated nuclear export mediated through a Rev-like nuclear export signal in the CaMKI-α regulatory domain. Interaction of CaMKI-α with a CRM1 complex in vitro is enhanced by incubation with calcium/calmodulin. Translocation of CaMKI-α into the nucleus involves a conserved sequence located within the catalytic core. Mutation of this sequence partially blocks nuclear entry of an export-impaired mutant of CaMKI-α

Towards a method for cryopreservation of mosquito vectors of human pathogens

Mosquito-borne diseases are responsible for millions of human deaths every year, posing a massive burden on global public health. Mosquitoes transmit a variety of bacteria, parasites and viruses. Mosquito control efforts such as insecticide spraying can reduce mosquito populations, but they must be sustained in order to have long term impacts, can result in the evolution of insecticide resistance, are costly, and can have adverse human and environmental effects. Technological advances have allowed genetic manipulation of mosquitoes, including generation of those that are still susceptible to insecticides, which has greatly increased the number of mosquito strains and lines available to the scientific research community. This generates an associated challenge, because rearing and maintaining unique mosquito lines requires time, money and facilities, and long-term maintenance can lead to adaptation to specific laboratory conditions, resulting in mosquito lines that are distinct from their wild-type counterparts. Additionally, continuous rearing of transgenic lines can lead to loss of genetic markers, genes and/or phenotypes. Cryopreservation of valuable mosquito lines could help circumvent these limitations and allow researchers to reduce the cost of rearing multiple lines simultaneously, maintain low passage number transgenic mosquitoes, and bank lines not currently being used. Additionally, mosquito cryopreservation could allow researchers to access the same mosquito lines, limiting the impact of unique laboratory or field conditions. Successful cryopreservation of mosquitoes would expand the field of mosquito research and could ultimately lead to advances that would reduce the burden of mosquito-borne diseases, possibly through rear-and-release strategies to overcome mosquito insecticide resistance. Cryopreservation techniques have been developed for some insect groups, including but not limited to fruit flies, silkworms and other moth species, and honeybees. Recent advances within the cryopreservation field, along with success with other insects suggest that cryopreservation of mosquitoes may be a feasible method for preserving valuable scientific and public health resources. In this review, we will provide an overview of basic mosquito biology, the current state of and advances within insect cryopreservation, and a proposed approach toward cryopreservation of Anopheles stephensi mosquitoes

Genetic Diversity of Polymorphic Vaccine Candidate Antigens (Apical Membrane Antigen-1, Merozoite Surface Protein-3, and Erythrocyte Binding Antigen-175) in Plasmodium falciparum Isolates from Western and Central Africa

The malaria vaccine candidate antigens erythrocyte binding antigen 175 (EBA-175), merozoite surface protein 3 (MSP-3), and apical membrane antigen (AMA-1) from Plasmodium falciparum isolates from countries in central and west Africa were assessed for allelic diversity. Samples were collected on filter paper from 600 P. falciparum-infected symptomatic patients in Cameroon, Republic of Congo, Burkina Faso, Ghana, and Senegal and screened for class-specific amplification fragments. Genetic diversity, assessed by mean heterozygosity, was comparable among countries. We detected a clinical increase in eba 175 F-allele frequency from west to east across the study region. No statistical difference in msp-3 allele distribution between countries was observed. The ama-1 3D7 alleles were present at a lower frequency in central Africa than in West Africa. We also detected little to no genetic differentiation among sampling locations. This finding indicates that, at least at the level of resolution offered by restriction fragment length polymorphism analysis, these antigens showed remarkable genetic homogeneity throughout the region sampled, perhaps caused by balancing selection to maintain a diverse array of antigen haplotyes

Effect of angiotensin-converting enzyme inhibitor and angiotensin receptor blocker initiation on organ support-free days in patients hospitalized with COVID-19

IMPORTANCE Overactivation of the renin-angiotensin system (RAS) may contribute to poor clinical outcomes in patients with COVID-19. Objective To determine whether angiotensin-converting enzyme (ACE) inhibitor or angiotensin receptor blocker (ARB) initiation improves outcomes in patients hospitalized for COVID-19. DESIGN, SETTING, AND PARTICIPANTS In an ongoing, adaptive platform randomized clinical trial, 721 critically ill and 58 non–critically ill hospitalized adults were randomized to receive an RAS inhibitor or control between March 16, 2021, and February 25, 2022, at 69 sites in 7 countries (final follow-up on June 1, 2022). INTERVENTIONS Patients were randomized to receive open-label initiation of an ACE inhibitor (n = 257), ARB (n = 248), ARB in combination with DMX-200 (a chemokine receptor-2 inhibitor; n = 10), or no RAS inhibitor (control; n = 264) for up to 10 days. MAIN OUTCOMES AND MEASURES The primary outcome was organ support–free days, a composite of hospital survival and days alive without cardiovascular or respiratory organ support through 21 days. The primary analysis was a bayesian cumulative logistic model. Odds ratios (ORs) greater than 1 represent improved outcomes. RESULTS On February 25, 2022, enrollment was discontinued due to safety concerns. Among 679 critically ill patients with available primary outcome data, the median age was 56 years and 239 participants (35.2%) were women. Median (IQR) organ support–free days among critically ill patients was 10 (–1 to 16) in the ACE inhibitor group (n = 231), 8 (–1 to 17) in the ARB group (n = 217), and 12 (0 to 17) in the control group (n = 231) (median adjusted odds ratios of 0.77 [95% bayesian credible interval, 0.58-1.06] for improvement for ACE inhibitor and 0.76 [95% credible interval, 0.56-1.05] for ARB compared with control). The posterior probabilities that ACE inhibitors and ARBs worsened organ support–free days compared with control were 94.9% and 95.4%, respectively. Hospital survival occurred in 166 of 231 critically ill participants (71.9%) in the ACE inhibitor group, 152 of 217 (70.0%) in the ARB group, and 182 of 231 (78.8%) in the control group (posterior probabilities that ACE inhibitor and ARB worsened hospital survival compared with control were 95.3% and 98.1%, respectively). CONCLUSIONS AND RELEVANCE In this trial, among critically ill adults with COVID-19, initiation of an ACE inhibitor or ARB did not improve, and likely worsened, clinical outcomes. TRIAL REGISTRATION ClinicalTrials.gov Identifier: NCT0273570

Comparative characterization of hexose transporters of Plasmodium knowlesi, Plasmodium yoelii and Toxoplasma gondii highlights functional differences within the apicomplexan family.

Chemotherapy of apicomplexan parasites is limited by emerging drug resistance or lack of novel targets. PfHT1, the Plasmodium falciparum hexose transporter 1, is a promising new drug target because asexual-stage malarial parasites depend wholly on glucose for energy. We have performed a comparative functional characterization of PfHT1 and hexose transporters of the simian malarial parasite P. knowlesi (PkHT1), the rodent parasite P. yoelii (PyHT1) and the human apicomplexan parasite Toxoplasma gondii ( T. gondii glucose transporter 1, TgGT1). PkHT1 and PyHT1 share >70% amino acid identity with PfHT1, while TgGT1 is more divergent (37.2% identity). All transporters mediate uptake of D-glucose and D-fructose. PyHT1 has an affinity for glucose ( K (m) approximately 0.12 mM) that is higher than that for PkHT1 ( K (m) approximately 0.67 mM) or PfHT1 ( K (m) approximately 1 mM). TgGT1 is highly temperature dependent (the Q (10) value, the fold change in activity for a 10 degrees C change in temperature, was >7) compared with Plasmodium transporters ( Q (10), 1.5-2.5), and overall has the highest affinity for glucose ( K (m) approximately 30 microM). Using active analogues in competition for glucose uptake, experiments show that hydroxyl groups at the C-3, C-4 and C-6 positions are important in interacting with PkHT1, PyHT1 and TgGT1. This study defines models useful to study the biology of apicomplexan hexose permeation pathways, as well as contributing to drug development

Arterialised hepatic nodules in the Fontan circulation: Hepatico-cardiac interactions

Hypervascular nodules occur commonly when there is hepatic venous outlet obstruction. Their nature and determinants in the Fontan circulation is poorly understood. We reviewed the records of 27 consecutive Fontan patients who had computerized tomography scan (CT) over a 4 year period for arterialised nodules and alterations in hepatic flow patterns during contrast enhanced CT scans and related these findings to cardiac characteristics. Mean patient age was 24 ± 5.8 years, (range 16.7–39.8) and mean Fontan duration was 16.8 ± 4.8 years (range 7.3–28.7). Twenty-two patients demonstrated a reticular pattern of enhancement, 4 a zonal pattern and only 1 demonstrated normal enhancement pattern. Seven (26%) patients had a median of 4 (range 1–22) arterialised nodules, mean size 1.8 cm (range 0.5 to 3.2 cm). All nodules were located in the liver periphery, their outer aspect lying within 2 cm of the liver margin. Patients with nodules had higher mean RA pressures (18 mmHg ± 5.6 vs. 13 mmHg ± 4, p = 0.025), whereas their mixed venous saturation and aortic saturation was not significantly different (70% ± 11 vs. 67% ± 9 and 92% ± 10 vs. 94% ± 4, p &gt; 0.05). Post-mortem histology suggests focal nodular hyperplasia is the underlying pathology. ConclusionsAbnormalities of hepatic blood flow and the presence of arterialised nodules are common in the failing Fontan circulation. They occur especially when central venous pressures are high, and very likely indicate arterialisation of hepatic blood flow and reciprocal portal venous deprivation. The underlying pathology is most likely focal nodular hyperplasia.<br/

The future of wildlife conservation funding: What options do U.S. college students support?

Insufficient funding is a major impediment to conservation efforts around the world. In the United States, a decline in hunting participation threatens sustainability of the “user-pay, public benefit” model that has supported wildlife conservation for nearly 100 years, forcing wildlife management agencies to contemplate alternative funding strategies. We investigated support for potential funding options among diverse college students, a rapidly expanding and politically active voting bloc with a potentially powerful influence on the future of conservation. From 2018 to 2020, we surveyed 17,203 undergraduate students at public universities across 22 states. Students preferred innovative approaches to conservation funding, with 72% supporting funding derived from industry sources (e.g., natural resource extraction companies), 63% supporting state sources (e.g., general sales tax), and 43% supporting conventional user-based sources such as license fees and excise taxes associated with outdoor recreation activities (e.g., hunting). Findings emphasize the need to broaden the base of support for conservation funding and highlight the importance of considering the preferences and perspectives of young adults and other diverse beneficiaries of wildlife conservation

Diverse pathways for climate resilience in marine fishery systems

Both the ecological and social dimensions of fisheries are being affected by climate change. As a result, policymakers, managers, scientists and fishing communities are seeking guidance on how to holistically build resilience to climate change. Numerous studies have highlighted key attributes of resilience in fisheries, yet concrete examples that explicitly link these attributes to social‐ecological outcomes are lacking. To better understand climate resilience, we assembled 18 case studies spanning ecological, socio‐economic, governance and geographic contexts. Using a novel framework for evaluating 38 resilience attributes, the case studies were systematically assessed to understand how attributes enable or inhibit resilience to a given climate stressor. We found population abundance, learning capacity, and responsive governance were the most important attributes for conferring resilience, with ecosystem connectivity, place attachment, and accountable governance scoring the strongest across the climate‐resilient fisheries. We used these responses to develop an attribute typology that describes robust sources of resilience, actionable priority attributes and attributes that are case specific or require research. We identified five fishery archetypes to guide stakeholders as they set long‐term goals and prioritize actions to improve resilience. Lastly, we found evidence for two pathways to resilience: (1) building ecological assets and strengthening communities, which we observed in rural and small‐scale fisheries, and (2) building economic assets and improving effective governance, which was demonstrated in urban and wealthy fisheries. Our synthesis presents a novel framework that can be directly applied to identify approaches, pathways and actionable levers for improving climate resilience in fishery systems