Middle East respiratory syndrome coronavirus (MERS-CoV) is a lineage C betacoronavirus that since its emergence in 2012 has caused outbreaks in human populations with case-fatality rates of ∼36%. As ...in other coronaviruses, the spike (S) glycoprotein of MERS-CoV mediates receptor recognition and membrane fusion and is the primary target of the humoral immune response during infection. Here we use structure-based design to develop a generalizable strategy for retaining coronavirus S proteins in the antigenically optimal prefusion conformation and demonstrate that our engineered immunogen is able to elicit high neutralizing antibody titers against MERS-CoV. We also determined high-resolution structures of the trimeric MERS-CoV S ectodomain in complex with G4, a stem-directed neutralizing antibody. The structures reveal that G4 recognizes a glycosylated loop that is variable among coronaviruses and they define four conformational states of the trimer wherein each receptor-binding domain is either tightly packed at the membrane-distal apex or rotated into a receptor-accessible conformation. Our studies suggest a potential mechanism for fusion initiation through sequential receptor-binding events and provide a foundation for the structure-based design of coronavirus vaccines.
The recent Zika virus (ZIKV) outbreak in Brazil has been directly linked to increased cases of microcephaly in newborns. Current evidence indicates that ZIKV is transmitted vertically from mother to ...fetus. However, the mechanism of intrauterine transmission and the cell types involved remain unknown. We demonstrate that the contemporary ZIKV strain PRVABC59 (PR 2015) infects and replicates in primary human placental macrophages, called Hofbauer cells, and to a lesser extent in cytotrophoblasts, isolated from villous tissue of full-term placentae. Viral replication coincides with induction of type I interferon (IFN), pro-inflammatory cytokines, and antiviral gene expression, but with minimal cell death. Our results suggest a mechanism for intrauterine transmission in which ZIKV gains access to the fetal compartment by directly infecting placental cells and disrupting the placental barrier.
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•Zika virus (ZIKV) infects and replicates in primary human placental macrophages•ZIKV also infects human placental cytotrophoblasts, but with delayed replication kinetics•ZIKV replication coincides with IFN and antiviral gene induction, but minimal cell death
The currently circulating Zika virus strain is directly linked to fetal microcephaly. However, the mechanism of intrauterine ZIKV transmission is unknown. Quicke et al. demonstrate that a contemporary ZIKV strain infects and replicates in primary human placental macrophages and cytotrophoblasts, suggesting a route for ZIKV to cross the placental barrier.
Purpose
Little is known about how to improve and create sustainable lifestyle behaviors of cancer survivors. Interventions based on social cognitive theory (SCT) have shown promise. This review ...examined the effect of SCT-based physical activity and nutrition interventions that target cancer survivors and identified factors associated with their efficacy.
Methods
A systematic search of seven databases identified randomized controlled trials that (i) targeted adult cancer survivors (any point from diagnosis); (ii) reported a primary outcome of physical activity, diet, or weight management; and (iii) included an SCT-based intervention targeting physical activity or diet. Qualitative synthesis and meta-analysis were conducted. Theoretical constructs and intervention characteristics were examined to identify factors associated with intervention efficacy.
Results
Eighteen studies (reported in 33 publications) met review inclusion criteria. Meta-analysis (
n
= 12) revealed a significant intervention effect for physical activity (standardized mean difference (SMD) = 0.33;
P
< 0.01). Most studies (six out of eight) that targeted dietary change reported significant improvements in at least one aspect of diet quality. No SCT constructs were associated with intervention effects. There were no consistent trends relating to intervention delivery method or whether the intervention targeted single or multiple behaviors.
Conclusions
SCT-based interventions demonstrate promise in improving physical activity and diet behavior in cancer survivors, using a range of intervention delivery modes. Further work is required to understand how and why these interventions offer promise for improving behavior.
Implications for Cancer Survivors
SCT-based interventions targeting diet or physical activity are safe and result in meaningful changes to diet and physical activity behavior that can result in health improvements.
Emerging coronaviruses (CoVs) cause severe disease in humans, but no approved therapeutics are available. The CoV nsp14 exoribonuclease (ExoN) has complicated development of antiviral nucleosides due ...to its proofreading activity. We recently reported that the nucleoside analogue GS-5734 (remdesivir) potently inhibits human and zoonotic CoVs
and in a severe acute respiratory syndrome coronavirus (SARS-CoV) mouse model. However, studies with GS-5734 have not reported resistance associated with GS-5734, nor do we understand the action of GS-5734 in wild-type (WT) proofreading CoVs. Here, we show that GS-5734 inhibits murine hepatitis virus (MHV) with similar 50% effective concentration values (EC
) as SARS-CoV and Middle East respiratory syndrome coronavirus (MERS-CoV). Passage of WT MHV in the presence of the GS-5734 parent nucleoside selected two mutations in the nsp12 polymerase at residues conserved across all CoVs that conferred up to 5.6-fold resistance to GS-5734, as determined by EC
The resistant viruses were unable to compete with WT in direct coinfection passage in the absence of GS-5734. Introduction of the MHV resistance mutations into SARS-CoV resulted in the same
resistance phenotype and attenuated SARS-CoV pathogenesis in a mouse model. Finally, we demonstrate that an MHV mutant lacking ExoN proofreading was significantly more sensitive to GS-5734. Combined, the results indicate that GS-5734 interferes with the nsp12 polymerase even in the setting of intact ExoN proofreading activity and that resistance can be overcome with increased, nontoxic concentrations of GS-5734, further supporting the development of GS-5734 as a broad-spectrum therapeutic to protect against contemporary and emerging CoVs.
Coronaviruses (CoVs) cause severe human infections, but there are no approved antivirals to treat these infections. Development of nucleoside-based therapeutics for CoV infections has been hampered by the presence of a proofreading exoribonuclease. Here, we expand the known efficacy of the nucleotide prodrug remdesivir (GS-5734) to include a group β-2a CoV. Further, GS-5734 potently inhibits CoVs with intact proofreading. Following selection with the GS-5734 parent nucleoside, 2 amino acid substitutions in the nsp12 polymerase at residues that are identical across CoVs provide low-level resistance to GS-5734. The resistance mutations decrease viral fitness of MHV
and attenuate pathogenesis in a SARS-CoV animal model of infection. Together, these studies define the target of GS-5734 activity and demonstrate that resistance is difficult to select, only partial, and impairs fitness and virulence of MHV and SARS-CoV, supporting further development of GS-5734 as a potential effective pan-CoV antiviral.
The toxicity and environmental persistence of anthropogenic per- and poly-fluoroalkyl substances (PFAS) are of global concern. To address legacy PFAS concerns in the United States, industry developed ...numerous replacement PFAS that commonly are treated as confidential information. To investigate the distribution of PFAS in New Jersey, soils collected from across the state were subjected to nontargeted mass-spectral analyses. Ten chloroperfluoropolyether carboxylates were tentatively identified, with at least three congeners in all samples. Nine congeners are ≥(CF
)
Distinct chemical formulas and structures, as well as geographic distribution, suggest airborne transport from an industrial source. Lighter congeners dispersed more widely than heavier congeners, with the most widely dispersed detected in an in-stock New Hampshire sample. Additional data were used to develop a legacy-PFAS fingerprint for historical PFAS sources in New Jersey.
Background
Clinical pathways are structured multidisciplinary care plans used by health services to detail essential steps in the care of patients with a specific clinical problem. They aim to link ...evidence to practice and optimise clinical outcomes whilst maximising clinical efficiency.
Objectives
To assess the effect of clinical pathways on professional practice, patient outcomes, length of stay and hospital costs.
Search methods
We searched the Database of s of Reviews of Effectiveness (DARE), the Effective Practice and Organisation of Care (EPOC) Register, the Cochrane Central Register of Controlled Trials (CENTRAL) and bibliographic databases including MEDLINE, EMBASE, CINAHL, NHS EED and Global Health. We also searched the reference lists of relevant articles and contacted relevant professional organisations.
Selection criteria
Randomised controlled trials, controlled clinical trials, controlled before and after studies and interrupted time series studies comparing stand alone clinical pathways with usual care as well as clinical pathways as part of a multifaceted intervention with usual care.
Data collection and analysis
Two review authors independently screened all titles to assess eligibility and methodological quality. Studies were grouped into those comparing clinical pathways with usual care and those comparing clinical pathways as part of a multifaceted intervention with usual care.
Main results
Twenty‐seven studies involving 11,398 participants met the eligibility and study quality criteria for inclusion. Twenty studies compared stand alone clinical pathways with usual care. These studies indicated a reduction in in‐hospital complications (odds ratio (OR) 0.58; 95% confidence interval (CI) 0.36 to 0.94) and improved documentation (OR 11.95: 95%CI 4.72 to 30.30). There was no evidence of differences in readmission to hospital or in‐hospital mortality. Length of stay was the most commonly employed outcome measure with most studies reporting significant reductions. A decrease in hospital costs/ charges was also observed, ranging from WMD +261 US$ favouring usual care to WMD ‐4919 US$ favouring clinical pathways (in US$ dollar standardized to the year 2000). Considerable heterogeneity prevented meta‐analysis of length of stay and hospital cost results. An assessment of whether lower hospital costs contributed to cost shifting to another health sector was not undertaken.
Seven studies compared clinical pathways as part of a multifaceted intervention with usual care. No evidence of differences were found between intervention and control groups.
Authors' conclusions
Clinical pathways are associated with reduced in‐hospital complications and improved documentation without negatively impacting on length of stay and hospital costs.
Purpose
Multiple health behaviours (not smoking, minimal alcohol consumption, and maintaining a healthy weight by having a healthy diet and regular physical activity) improve quality of life and ...longevity of cancer survivors. Despite international guidelines, there are no existing reviews that synthesise cancer survivors’ adherence to healthy lifestyle recommendations.
Method
Five databases (Embase, MEDLINE, PsycINFO, Web of Science, and Google Scholar) were searched for relevant articles published from 2007 until January 2018. Studies reporting adult cancer survivors’ adherence to at least two lifestyle behaviours (body mass index, physical activity, smoking, fruit and vegetable intake, fiber intake, red meat intake, caloric intake, sodium intake, and alcohol consumption) based on the World Cancer Research Fund/American Institute for Cancer Research (WCRF/AICR) recommendations were included in the review. The pooled prevalence of adherence to single and multiple behaviours was calculated using a random-effects model. Subgroup analysis (mean years of survival and publication year) was undertaken.
Results
A total of 3322 articles were identified. Of these, 51 studies matched the inclusion criteria, presenting data from 2,620,586 adult cancer survivors. Adherence to single behaviours, which was estimated from studies that assessed at least two health behaviours, was highest for not smoking (PE 87%; 95% CI, 85%, 88%) and low or no alcohol intake (PE 83%; 95% CI, 81%, 86%), and lowest for fiber intake (PE 31%; 95% CI, 21%, 40%). Adherence to multiple healthy behaviours (13 studies), ranged from 7 to 40% (pooled estimate (PE) 23%; 95% CI, 17%, 30%). Recent survivors (
<
5-year survival time) had relatively better adherence to multiple behaviours (PE 31%; 95% CI, 27%, 35%) than long-term (> 5 years) survivors (PE 25%; 95% CI, 14%, 36%). Adherence to multiple behaviours improved over time since 2007.
Conclusion
Adherence to physical activity, dietary, and multiple lifestyle behaviours recommendations was low amongst cancer survivors. Recent cancer survivors were relatively more adherent to WCRF/AICR recommendations compared to long-term survivors.
Implications for Cancer Survivors
Health promotion programs help support healthy lifestyle behaviours of cancer survivors.
PROSPERO registration number: CRD42018091663
There is a growing awareness that undertaking qualitative research is an embodied experience and that researchers may be emotionally affected by the work that they do. Despite the interest in the ...emotional nature of qualitative research, there is very little empirical evidence about the researchers' experiences of undertaking qualitative research. A grounded theory analysis of one-on-one interviews with thirty public health researchers working on a qualitative project provided both theoretical and empirical evidence that qualitative researchers undertake emotion work throughout their research projects. The findings provide examples of researchers doing emotion work in their research projects; highlight some of the consequences of emotion work and offer some suggestions for researcher self-care.
Unlike white and brown adipose tissues, the bone marrow adipocyte (BMA) exists in a microenvironment containing unique populations of hematopoietic and skeletal cells. To study this microenvironment ...at the sub-cellular level, we performed a three-dimensional analysis of the ultrastructure of the BMA niche with focused ion beam scanning electron microscopy (FIB-SEM). This revealed that BMAs display hallmarks of metabolically active cells including polarized lipid deposits, a dense mitochondrial network, and areas of endoplasmic reticulum. The distinct orientations of the triacylglycerol droplets suggest that fatty acids are taken up and/or released in three key areas – at the endothelial interface, into the hematopoietic milieu, and at the bone surface. Near the sinusoidal vasculature, endothelial cells send finger-like projections into the surface of the BMA which terminate near regions of lipid within the BMA cytoplasm. In some regions, perivascular cells encase the BMA with their flattened cellular projections, limiting contacts with other cells in the niche. In the hematopoietic milieu, BMAT adipocytes of the proximal tibia interact extensively with maturing cells of the myeloid/granulocyte lineage. Associations with erythroblast islands are also prominent. At the bone surface, the BMA extends organelle and lipid-rich cytoplasmic regions toward areas of active osteoblasts. This suggests that the BMA may serve to partition nutrient utilization between diverse cellular compartments, serving as an energy-rich hub of the stromal-reticular network. Lastly, though immuno-EM, we've identified a subset of bone marrow adipocytes that are innervated by the sympathetic nervous system, providing an additional mechanism for regulation of the BMA. In summary, this work reveals that the bone marrow adipocyte is a dynamic cell with substantial capacity for interactions with the diverse components of its surrounding microenvironment. These local interactions likely contribute to its unique regulation relative to peripheral adipose tissues.
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•BMAs display hallmarks of metabolically active cells including multiple lipid droplets and a dense mitochondrial network.•BMA lipid droplet remodeling is compartmentalized - polarized toward the vasculature, hematopoietic cells, or bone surface.•Bone marrow adipocytes are directly associated with the sinusoidal vasculature and may be encased by perivascular cells.•Bone marrow adipocytes interface directly with erythroblast islands and cells of the myeloid/granulocyte lineage.•A subset of bone marrow adipocytes are innervated by the sympathetic nervous system.
The emergence of coronaviruses (CoVs) into human populations from animal reservoirs has demonstrated their epidemic capability, pandemic potential, and ability to cause severe disease. However, no ...antivirals have been approved to treat these infections. Here, we demonstrate the potent antiviral activity of a broad-spectrum ribonucleoside analogue, β-
d
-
N
4
-hydroxycytidine (NHC), against two divergent CoVs. Viral proofreading activity does not markedly impact sensitivity to NHC inhibition, suggesting a novel interaction between a nucleoside analogue inhibitor and the CoV replicase. Further, passage in the presence of NHC generates only low-level resistance, likely due to the accumulation of multiple potentially deleterious transition mutations. Together, these data support a mutagenic mechanism of inhibition by NHC and further support the development of NHC for treatment of CoV infections.
Coronaviruses (CoVs) have emerged from animal reservoirs to cause severe and lethal disease in humans, but there are currently no FDA-approved antivirals to treat the infections. One class of antiviral compounds, nucleoside analogues, mimics naturally occurring nucleosides to inhibit viral replication. While these compounds have been successful therapeutics for several viral infections, mutagenic nucleoside analogues, such as ribavirin and 5-fluorouracil, have been ineffective at inhibiting CoVs. This has been attributed to the proofreading activity of the viral 3′-5′ exoribonuclease (ExoN). β-
d
-
N
4
-Hydroxycytidine (NHC) (EIDD-1931; Emory Institute for Drug Development) has recently been reported to inhibit multiple viruses. Here, we demonstrate that NHC inhibits both murine hepatitis virus (MHV) (50% effective concentration EC
50
= 0.17 μM) and Middle East respiratory syndrome CoV (MERS-CoV) (EC
50
= 0.56 μM) with minimal cytotoxicity. NHC inhibited MHV lacking ExoN proofreading activity similarly to wild-type (WT) MHV, suggesting an ability to evade or overcome ExoN activity. NHC inhibited MHV only when added early during infection, decreased viral specific infectivity, and increased the number and proportion of G:A and C:U transition mutations present after a single infection. Low-level NHC resistance was difficult to achieve and was associated with multiple transition mutations across the genome in both MHV and MERS-CoV. These results point to a virus-mutagenic mechanism of NHC inhibition in CoVs and indicate a high genetic barrier to NHC resistance. Together, the data support further development of NHC for treatment of CoVs and suggest a novel mechanism of NHC interaction with the CoV replication complex that may shed light on critical aspects of replication.
IMPORTANCE
The emergence of coronaviruses (CoVs) into human populations from animal reservoirs has demonstrated their epidemic capability, pandemic potential, and ability to cause severe disease. However, no antivirals have been approved to treat these infections. Here, we demonstrate the potent antiviral activity of a broad-spectrum ribonucleoside analogue, β-
d
-
N
4
-hydroxycytidine (NHC), against two divergent CoVs. Viral proofreading activity does not markedly impact sensitivity to NHC inhibition, suggesting a novel interaction between a nucleoside analogue inhibitor and the CoV replicase. Further, passage in the presence of NHC generates only low-level resistance, likely due to the accumulation of multiple potentially deleterious transition mutations. Together, these data support a mutagenic mechanism of inhibition by NHC and further support the development of NHC for treatment of CoV infections.
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