A late-Ediacaran crown-group sponge animal.

Sponges are the most basal metazoan phylum1 and may have played important roles in modulating the redox architecture of Neoproterozoic oceans2. Although molecular clocks predict that sponges diverged in the Neoproterozoic era3,4, their fossils have not been unequivocally demonstrated before the Cambrian period5-8, possibly because Precambrian sponges were aspiculate and non-biomineralized9. Here we describe a late-Ediacaran fossil, Helicolocellus cantori gen. et sp. nov., from the Dengying Formation (around 551-539 million years ago) of South China. This fossil is reconstructed as a large, stemmed benthic organism with a goblet-shaped body more than 0.4 m in height, with a body wall consisting of at least three orders of nested grids defined by quadrate fields, resembling a Cantor dust fractal pattern. The resulting lattice is interpreted as an organic skeleton comprising orthogonally arranged cruciform elements, architecturally similar to some hexactinellid sponges, although the latter are built with biomineralized spicules. A Bayesian phylogenetic analysis resolves H. cantori as a crown-group sponge related to the Hexactinellida. H. cantori confirms that sponges diverged and existed in the Precambrian as non-biomineralizing animals with an organic skeleton. Considering that siliceous biomineralization may have evolved independently among sponge classes10-13, we question the validity of biomineralized spicules as a necessary criterion for the identification of Precambrian sponge fossils.

Advances in treatment strategies based on scavenging reactive oxygen species of nanoparticles for atherosclerosis.

The development of atherosclerosis (AS) is closely linked to changes in the plaque microenvironment, which consists primarily of the cells that form plaque and the associated factors they secrete. The onset of inflammation, lipid deposition, and various pathological changes in cellular metabolism that accompany the plaque microenvironment will promote the development of AS. Numerous studies have shown that oxidative stress is an important condition that promotes AS. The accumulation of reactive oxygen species (ROS) is oxidative stress's most important pathological change. In turn, the effects of ROS on the plaque microenvironment are complex and varied, and these effects are ultimately reflected in the promotion or inhibition of AS. This article reviews the effects of ROS on the microenvironment of atherosclerotic plaques and their impact on disease progression over the past five years and focuses on the progress of treatment strategies based on scavenging ROS of nanoparticles for AS. Finally, we also discuss the prospects and challenges of AS treatment.

[Vein Nerve Conduit Supported by Vascular Stent in the Regeneration of Peripheral Nerve in Rabbits].

OBJECTIVE: To evaluate the effectiveness of autologous vein nerve conduit supported by vascular stent in repairing a 10 mm gap peroneal nerve in white New Zealand rabbits. METHODS: 30 New Zealand rabbits were randomly divided into three groups: autologous nerve group (group A),conventional autologous vein nerve conduit group (group B),autologous vein nerve conduit supported by vascular stent group (group C). 10 mm common peroneal nerve was cut off. In groups A,the peroneal nerve was turned 180 ° before suturing. In group B and group C,20 mm long external jugular vein was cut and removed. After dilution of venous retraction,the venous bridge filled the gap of the nerve defect in group B. In group C,a blood vessel stent was placed for accessing the external jugular vein,and then connected to the nerve defect. Ulnar ulcer was observed after operations. Reflex score of left foot toe was recorded. The nerve regeneration and functional recovery was assessed through electrophysiological examinations,comparison of wet mass ratio between the left and right hind limb gastrocnemius,morphological observations,transmission electron microscopy 12 weeks after operations. RESULTS: Group B had the lowest scoring of toespreading reflex,whereas Group A had the highest scoring of toespreading reflex. There was a statistically significant difference in the scoring of toespreading reflex between group A and group C. In terms of the diameter of regenerated nerve fiber and the thickness of regenerated myelin sheath,no statistically significant ( P>0.05) difference was found between group A and group C,whereas the difference was significant ( P<0.05) between groups A/C and group B. The presence of peripheral nerves found in light microscopic examinations revealed normal characteristics of myelinated fibers in all groups. The myelinated axon profile was almost equal between group B and group C under electron microscopic examinations. However,more degenerated axons with disturbed contoursin were found in group B compared with group C. CONCLUSION: Autologous vein nerve conduit supported by vascular stent increases regeneration of nerves.

[Comparison of USS Combined with Sacroiliac Screw and CMAS Iliosacral Fixation in the Treatment of Unstable Sacral Fracture].

OBJECTIVE: To compare the effectiveness of two lumbopelvic fixation procedures for treating unstable sacral fractures. METHODS: The clinical data of 47 patients were treated for unstable sacral fractures in the West China Hospital of Sichuan University from January 2010 to December 2014 were reviewed. Twentytwo patients (28 sides) were treated with USS combined with iliosacral screw (group A),while 25 patients (39 sides) were treated with closed multiaxial screws (CMAS) iliosacral fixation system combined with Posterior Segmental Spinal Fixation system (group B). The outcomes of the two procedures were compared using the following indicators: length of operations,amount of intraoperative blood loss,MATTA score of fracture reduction,MAJEED function score one year postoperation,postoperative complications,and GIBBONS Classification of sacral nerve injury in patients with sacral nerve symptoms. RESULTS: Group A had longer operations [(121.4±5.1) min] than group B [(110.6±4.5) min, P<0.05]. Group A had larger intraoperative blood loss [(618±45) mL] than group B [(570±40) mL, P<0.05]. Both groups had two cases of wound infection after operations that were cured by debridement and antibiotic therapy. According to the MATTA scoring criteria,group A had 92.9% excellent and good fracture reduction,compared with 97.5% in group B ( P<0.05). According to the MAJEED functional scoring criteria,group A had 86.4% excellent and good clinical functions,compared with 92.0% in group A ( P<0.05). The GIBBONS criteria indicated that neurological functions of both groups improved significantly after operations ( P<0.05),but no significant difference appeared between the two groups ( P>0.05). CONCLUSION: CMAS iliosacral fixation system is better for treating unstable sacral fractures compared with USS combined with iliosacral screws.

Mice fatal pneumonia model induced by less-virulent Streptococcus pneumoniae via intratracheal aerosolization.

Aim: Animal models of fatal pneumonia caused by Streptococcus pneumoniae (Spn) have not been reliably generated using many strains of less virulent serotypes. Materials & methods: Pulmonary infection of a less virulent Spn serotype1 strain in the immunocompetent mice was established via the intratracheal aerosolization (ITA) route. The survival, local and systemic bacterial spread, pathological changes and inflammatory responses of this model were compared with those of mice challenged via the intratracheal instillation, intranasal instillation and intraperitoneal injection routes. Results: ITA and intratracheal instillation both induced fatal pneumonia; however, ITA resulted in better lung bacterial deposition and distribution, pathological homogeneity and delivery efficiency. Conclusion: ITA is an optimal route for developing animal models of severe pulmonary infections.

What is this article about? Streptococcus pneumoniae (Spn), a type of bacteria, can cause serious illness and death in otherwise healthy people. One way that we study pneumonia is using animals. However, pneumonia in animals infected with Spn in the laboratory does not mimic that in humans very well. To study this illness, we need a new way to set up a proper animal model.What were the results? This study set up a method called intratracheal aerosolization (ITA). In ITA, bacteria can form small droplets called aerosols and reach the deepest parts of a mouse's lung. ITA can cause deadly illness in mice infected with Spn, even if the mice are healthy.What do the results of the study mean? The ITA method could be a useful tool to set up animal models of serious pneumonia with less virulent bacteria.

Tonian carbonaceous compressions indicate that Horodyskia is one of the oldest multicellular and coenocytic macro-organisms.

Macrofossils with unambiguous biogenic origin and predating the one-billion-year-old multicellular fossils Bangiomorpha and Proterocladus interpreted as crown-group eukaryotes are quite rare. Horodyskia is one of these few macrofossils, and it extends from the early Mesoproterozoic Era to the terminal Ediacaran Period. The biological interpretation of this enigmatic fossil, however, has been a matter of controversy since its discovery in 1982, largely because there was no evidence for the preservation of organic walls. Here we report new carbonaceous compressions of Horodyskia from the Tonian successions (~950-720 Ma) in North China. The macrofossils herein with bona fide organic walls reinforce the biogenicity of Horodyskia. Aided by the new material, we reconstruct Horodyskia as a colonial organism composed of a chain of organic-walled vesicles that likely represent multinucleated (coenocytic) cells of early eukaryotes. Two species of Horodyskia are differentiated on the basis of vesicle sizes, and their co-existence in the Tonian assemblage provides a link between the Mesoproterozoic (H. moniliformis) and the Ediacaran (H. minor) species. Our study thus provides evidence that eukaryotes have acquired macroscopic size through the combination of coenocytism and colonial multicellularity at least ~1.48 Ga, and highlights an exceptionally long range and morphological stasis of this Proterozoic macrofossils.

Data-driven trajectory tracking control for autonomous underwater vehicle based on iterative extended state observer.

In this study, we explore the precise trajectory tracking control problem of autonomous underwater vehicle (AUV) under the disturbance of the underwater environment. First, a model-free adaptive control (MFAC) is designed based on data-driven ideology and a full-form dynamic linearization (FFDL) method is utilized to online estimate time-varying parameter pseudo gradient (PG) to establish an equivalent data model of AUV motion. Second, the iterative extended state observer (IESO) scheme is designed to combine with FFDL-MFAC. Because the proposed novel controller is able to learn from repeated iterations, the proposed novel controller can estimate and compensate the model approximation error produced by external environmental unknown disturbance. Third, three-dimensional motion is decoupled into horizontal and vertical and a multi closed-loop control structure is designed that exhibits faster convergence rate and reduces sensitivity to parameter jumps than single closed-loop system. Finally, two simulation scenarios are designed featuring non external disturbance and Gaussian noise of signal-to-noise ratio of 90 dB. The simulation results reveal the superiority of FFDL. Furthermore, we adpot the technical parameters data of T-SEA I AUV to conduct numerical simulation, aunderwater trajectory as the tracking scenario and set waves to 0.5 m and current to 0.2 m/s to simulate Lv.2 ocean conditions of "International Ocean State Standard". The simulation results demonstrate the effectiveness and robustness of the proposed tracking control algorithm.

Proportion of stable femoral neck fracture types in different age groups: a population-based study.

OBJECTIVE: The treatment and incidence of femoral neck fracture (FNF) in older patients is controversial. We investigated the new AO (Arbeitsgemeinschaft für Osteosynthese) classification in patients with FNF by age to determine the proportions of stable fracture and change trends according to patients' age. METHODS: We divided patients with FNF hospitalized in Xi'an Honghui Hospital from 2018 to 2020 into five groups according to age: young (<50 years), middle-aged (50-59 years), young-elderly (60-69 years), middle-elderly (70-79 years), and very elderly (≥80 years) groups. We retrospectively collected data of patients' sex, admission date, fracture side, mechanism of injury, and new AO classification. RESULTS: In total, 2071 patients were included for analysis, with 1329 women (64.2%); 1106 patients (53.4%) had left-side fracture. The main mechanism of injury was falling. In the young-elderly, middle-elderly, and very-elderly groups, 33.3%, 29.2%, and 24.1% had stable fracture type, respectively). The proportion of patients with FNF did not show a change trend by age during the 3-year investigation period. CONCLUSION: In our study, the proportion of older patients with FNF did not increase, and as many as a third of patients with FNF aged 50 to 70 years had stable fracture.

Ship Radiated Noise Recognition Technology Based on ML-DS Decision Fusion.

Ship radiated noise is an important information source of underwater acoustic targets, and it is of great significance to the identification and classification of ship targets. However, there are a lot of interference noises in the water, which leads to the reduction of the model recognition rate. Therefore, the recognition results of radiated noise targets are severely affected. This paper proposes a machine learning Dempster-Shafer (ML-DS) decision fusion method. The algorithm combines the recognition results of machine learning and deep learning. It uses evidence-based decision-making theory to realize feature fusion under different neural network classifiers and improve the accuracy of judgment. First, deep learning algorithms are used to classify two-dimensional spectrogram features and one-dimensional amplitude features extracted from CNN and LSTM networks. The machine learning algorithm SVM is used to classify the chromaticity characteristics of radiated noise. Then, according to the classification results of different classifiers, a basic probability assignment model (BPA) was designed to fuse the recognition results of the classifiers. Finally, according to the classification characteristics of machine learning and deep learning, combined with the decision-making of D-S evidence theory of different times, the decision-making fusion of radiated noise is realized. The results of the experiment show that the two fusions of deep learning combined with one fusion of machine learning can significantly improve the recognition results of low signal-to-noise ratio (SNR) datasets. The lowest fusion recognition result can reach 76.01%, and the average fusion recognition rate can reach 94.92%. Compared with the traditional single feature recognition algorithm, the recognition accuracy is greatly improved. Compared with the traditional one-step fusion algorithm, it can effectively integrate the recognition results of heterogeneous data and heterogeneous networks. The identification method based on ML-DS proposed in this paper can be applied in the field of ship radiated noise identification.

Spherical-view photoacoustic tomography for monitoring in vivo placental function.

Photoacoustic tomography has great potential to image dynamic functional changes in vivo. Many tomographic systems are built with a circular view geometry, necessitating a linear translation along one axis of the subject to obtain a three-dimensional volume. In this work, we evaluated a prototype spherical view photoacoustic tomographic system which acquires a 3D volume in a single scan, without linear translation. We simultaneously measured relative hemoglobin oxygen saturation in multiple placentas of pregnant mice under oxygen challenge. We also synthesized a folate-conjugated indocyanine green (ICG) contrast agent to image folate kinetics in the placenta. Photoacoustic tomography performed at the wavelength of peak optical absorption of our contrast agent revealed increased ICG signal over time. Through these phantom and in vivo studies, we have demonstrated that the spherical view 3D photoacoustic tomographic system achieves high sensitivity and fast image acquisition, enabling in vivo experiments to assess physiological and molecular dynamics.

Efficacy and safety of riluzole for depressive disorder: A systematic review and meta-analysis of randomized placebo-controlled trials.

Glutamatergic modulators may have therapeutic potential in the treatment of depressive disorder (DD), riluzole, as a modulating drug of the glutamatergic system, its antidepressant efficacy and safety of riluzole for DD are inconsistent. This meta-analysis was performed to determine the efficacy and safety of riluzole used for DD. A systematic literature search was performed using PubMed, Embase, Cochrane Library, Web of Science, VIP and other databases from 1980 to 2019. The primary outcome was change in depression severity and meta-analysis was performed using comprehensive meta-analysis software. Seven randomized controlled trials (RCTs) were included. There was some difference in depression severity change in riluzole-citalopram therapy. No significant differences were observed in response rate, remission rate, relapse rate and adverse events, while, the relapse time in riluzole group was longer than placebo group. In this meta-analysis riluzole showed no antidepressant efficacy compared to placebo in monotherapy or riluzole-ketamine combined therapy, while it might relieve depression severity to some extent in riluzole-citalopram therapy. Furthermore, riluzole showed favorable safety for DD. The longer relapse time of riluzole group might have clinical significance to some extent, although this had no statistical difference. More studies are needed to clarify the potential association between riluzole and DD.

Comparison of microplastic pollution in different water bodies from urban creeks to coastal waters.

Although freshwater and estuary systems are recognized as origins and transport pathways of plastics to the oceans, there is a lack of comparison of microplastics in different water bodies or river networks. In the present study, the spatial distribution of microplastics was compared across different water bodies, including city creeks (Shanghai), rivers (Suzhou River and Huangpu River), an estuary (Yangtze Estuary) and coastal waters (East China Sea) in the Yangtze Delta area. Significant spatial differences of microplastic abundances were revealed across the sampling areas. The results showed that the abundance of microplastics was higher (1.8-2.4 items/L) in freshwater bodies than that in estuarine and coastal water (0.9 items/L). In the Suzhou River and the Huangpu River, microplastics showed trends of increasing abundance downstream, where the peak of microplastic pollution is closer to the city center and the estuary. In respect of abundance, microplastics are likely to be transported from pollution sources to sink areas via river networks. The proportion of fibers was the highest in city creeks (88%), followed by the Suzhou River (85%), the Huangpu River (81%), the Yangtze Estuary (66%) and the East China Sea (37%). Similarly, polyesters dominated in city creeks and rivers. The results suggest that both the abundance and properties of microplastic pollution varies across different water bodies. Microplastic pollution in small freshwater bodies is more serious than in estuarine and coastal waters. Therefore, we support prioritization of water monitoring for microplastics within entire river networks, instead of single water body surveys.

Efficacy and Safety of Tranexamic Acid in Reducing Blood Loss of Lower Extremity Osteotomy in Peri-acetabulum and High Tibia: A Systematic Review and Meta-analysis.

OBJECTIVE: To assess the efficacy of tranexamic acid (TXA) in reducing total blood loss and transfusion, and the risk of thromboembolic events in patients undergoing periacetabular osteotomy (PAO) and high tibial osteotomy (HTO). METHODS: A systematic literature search was performed using PubMed, the Cochrane Central Register of Controlled Trials (CENTRAL), Embase (Ovid), Medline (Ovid), and Web of Science. ClinicalTrials.gov, American Academy of Orthopaedic Surgeons (AAOS), and Orthopaedic Trauma Association (OTA) conference proceedings were also searched to gain more eligible studies. The primary outcome measure was total blood loss and the blood transfusion rate of the TXA group versus control. The meta-analysis was conducted using the RevMan 5.3 and Stata 14.0 software. RESULTS: A total of six studies were included involving 665 patients. Three studies were PAO, and the other three were HTO. The total blood loss in PAO (WMD, -330.49; 95% CI, -390.16 to -270.83; P < 0.001) and HTO (WMD, -252.50; 95% CI, -356.81 to -148.18; P < 0.001) and hemoglobin decline (WMD, -0.74; 95% CI, -1.09 to -0.38; P < 0.001) were significantly less in the TXA group than in the control group. TXA could reduce transfusion rates in PAO (RR, 0.26; 95% CI, 0.09 to 0.75; P = 0.01) but had no effect on HTO (RR, 0.20; 95% CI, 0.01 to 4.10; P = 0.30). The wound complications (RR, 0.62; 95% CI, 0.13 to 2.94; P = 0.54) had no significant difference between TXA and control groups. CONCLUSIONS: This meta-analysis demonstrated that TXA reduces total blood loss and hemoglobin decline in patients undergoing PAO and is safe, but it has little benefit in regard to reducing transfusion rates or wound complications in HTO, so TXA might be unwarranted for routine use for HTO.

Imaging placental function: current technology, clinical needs, and emerging modalities.

The function of the placenta is challenging to characterize and as a result is understudied, despite the growing awareness of the impact of the placental environment on human health and development. Medical imaging has the potential to improve our ability to screen for diseases associated with placental insufficiency, and improve the monitoring and treatment of complex obstetric patients. This review provides an overview of clinical and preclinical imaging modalities currently available for assessing placental function, with an emphasis on emerging preclinical imaging modalities; as a group, these emerging modalities provide exceptional contrast and sensitivity for multimodal functional and molecular imaging of the placenta. Analysis of the successes and failures of medical imaging thus far provides guidance for the research community seeking to develop new imaging systems to assess placental function.