Allometric Scaling Reveals Evolutionary Constraint on Odonata Wing Cellularity via Critical Crack Length

Scaling in insect wings is a complex phenomenon that seems pivotal in maintaining wing functionality. In this study, the relationship between wing size and the size, location, and shape of wing cells in dragonflies and damselflies (Odonata) is investigated, aiming to address the question of how these factors are interconnected. To this end, WingGram, the recently developed computer‐vision‐based software, is used to extract the geometric features of wing cells of 389 dragonflies and damselfly wings from 197 species and 16 families. It has been found that the cell length of the wings does not depend on the wing size. Despite the wide variation in wing length (8.42 to 56.5 mm) and cell length (0.1 to 8.5 mm), over 80% of the cells had a length ranging from 0.5 to 1.5 mm, which was previously identified as the critical crack length of the membrane of locust wings. An isometric scaling of cells is also observed with maximum size in each wing, which increased as the size increased. Smaller cells tended to be more circular than larger cells. The results have implications for bio‐mimetics, inspiring new materials and designs for artificial wings with potential applications in aerospace engineering and robotics

Diagnostic performance of Wells score combined with point-of-care lung and venous ultrasound in suspected pulmonary embolism

Objective: Lung and venous ultrasound are bedside diagnostic tools increasingly used in the early diagnostic approach of suspected pulmonary embolism (PE). However, the possibility of improving the conventional prediction rule for PE by integrating ultrasound has never been investigated. Methods: We performed lung and venous ultrasound in consecutive patients suspected of PE in four emergency departments. Conventional Wells score (Ws) was adjudicated by the attending physician, and ultrasound was performed by one of 20 investigators. Signs of deep venous thrombosis (DVT) at venous ultrasound and signs of pulmonary infarcts or alternative diagnoses at lung ultrasound were considered to recalculate two items of the Ws: signs and symptoms of DVT and alternative diagnosis less likely than PE. The diagnostic performances of the ultrasound-enhanced Ws (USWs) and Ws were then compared after confirmation of the final diagnosis. Results: A total of 446 patients were studied. PE was confirmed in 125 patients (28%). USWs performed significantly better than Ws, with a sensitivity of 69.6% versus 57.6% and a specificity of 88.2% versus 68.2%. In combination with D-dimer, USWs showed an optimal failure rate (0.8%) and a significantly superior efficiency than Ws (32.3% vs. 27.2%). A strategy based on lung and venous ultrasound combined with D-dimer would allow to avoid CT pulmonary angiography in 50.5% of patients with suspected PE, compared to 27.2% when the rule without ultrasound is applied. Conclusions: A pretest risk stratification enhanced by ultrasound of lung and venous performs better than Ws in the early diagnostic process of PE

Vaccination with murid herpesvirus-4 glycoprotein B reduces viral lytic replication but does not induce detectable virion neutralization

Herpesviruses characteristically disseminate from immune hosts. Therefore in the context of natural infection, antibody neutralizes them poorly. Murid herpesvirus-4 (MuHV-4) provides a tractable model with which to understand gammaherpesvirus neutralization. MuHV-4 virions blocked for cell binding by immune sera remain infectious for IgG-Fc receptor+ myeloid cells, so broadly neutralizing antibodies must target the virion fusion complex – glycoprotein B (gB) or gH/gL. While gB-specific neutralizing antibodies are rare, its domains I+II (gB-N) contain at least one potent neutralization epitope. Here, we tested whether immunization with recombinant gB presenting this epitope could induce neutralizing antibodies in naive mice and protect them against MuHV-4 challenge. Immunizing with the full-length gB extracellular domain induced a strong gB-specific antibody response and reduced MuHV-4 lytic replication but did not induce detectable neutralization. gB-N alone, which more selectively displayed pre-fusion epitopes including neutralization epitopes, also failed to induce neutralizing responses, and while viral lytic replication was again reduced this depended completely on IgG Fc receptors. gB and gB-N also boosted neutralizing responses in only a minority of carrier mice. Therefore, it appears that neutralizing epitopes on gB are intrinsically difficult for the immune response to target

Constitutively elevated levels of SOCS1 suppress innate responses in DF-1 immortalised chicken fibroblast cells.

The spontaneously immortalised DF-1 cell line is rapidly replacing its progenitor primary chicken embryo fibroblasts (CEFs) for studies on avian viruses such as avian influenza but no comprehensive study has as yet been reported comparing their innate immunity phenotypes. We conducted microarray analyses of DF-1 and CEFs, under both normal and stimulated conditions using chicken interferon-α (chIFN-α) and the attenuated infectious bursal disease virus vaccine strain PBG98. We found that DF-1 have an attenuated innate response compared to CEFs. Basal expression levels of Suppressor of Cytokine Signalling 1 (chSOCS1), a negative regulator of cytokine signalling in mammals, are 16-fold higher in DF-1 than in CEFs. The chSOCS1 “SOCS box” domain (which in mammals, interacts with an E3 ubiquitin ligase complex) is not essential for the inhibition of cytokine-induced JAK/STAT signalling activation in DF-1. Overexpression of SOCS1 in chIFN-α-stimulated DF-1 led to a relative decrease in expression of interferon-stimulated genes (ISGs; MX1 and IFIT5) and increased viral yield in response to PBG98 infection. Conversely, knockdown of SOCS1 enhanced induction of ISGs and reduced viral yield in chIFN-α-stimulated DF-1. Consequently, SOCS1 reduces induction of the IFN signalling pathway in chicken cells and can potentiate virus replication