Microbial diversity and their extracellular enzyme activities among different soil particle sizes in mossy biocrust under N limitation in the southeastern Tengger Desert, China.

Introduction: Mossy biocrust represents a stable stage in the succession of biological soil crust in arid and semi-arid areas, providing a microhabitat that maintains microbial diversity. However, the impact of mossy biocrust rhizoid soil and different particle sizes within the mossy biocrust layer and sublayer on microbial diversity and soil enzyme activities remains unclear. Methods: This study utilized Illumina MiSeq sequencing and high-throughput fluorometric technique to assess the differences in microbial diversity and soil extracellular enzymes between mossy biocrust rhizoid soil and different particle sizes within the mossy biocrust sifting and sublayer soil. Results: The results revealed that the total organic carbon (TOC), total nitrogen (TN), ammonium (NH4+) and nitrate (NO3-) in mossy biocrust rhizoid soil were the highest, with significantly higher TOC, TN, and total phosphorus (TP) in mossy biocrust sifting soil than those in mossy biocrust sublayer soil. Extracellular enzyme activities (EAAs) exhibited different responses to various soil particle sizes in mossy biocrust. Biocrust rhizoid soil (BRS) showed higher C-degrading enzyme activity and lower P-degrading enzyme activity, leading to a significant increase in enzyme C: P and N: P ratios. Mossy biocrust soils were all limited by microbial relative nitrogen while pronounced relative nitrogen limitation and microbial maximum relative carbon limitation in BRS. The diversity and richness of the bacterial community in the 0.2 mm mossy biocrust soil (BSS0.2) were notably lower than those in mossy biocrust sublayer, whereas the diversity and richness of the fungal community in the rhizoid soil were significantly higher than those in mossy biocrust sublayer. The predominant bacterial phyla in mossy biocrust were Actinobacteriota, Protebacteria, Chloroflexi, and Acidobacteriota, whereas in BSS0.2, the predominant bacterial phyla were Actinobacteriota, Protebacteria, and Cyanobacteria. Ascomycota and Basidiomycota were dominant phyla in mossy biocrust. The bacterial and fungal community species composition exhibited significant differences. The mean proportions of Actinobacteriota, Protebacteria, Chloroflexi, Acidobacteriota, Acidobacteria, Cyanobacteria, and Bacteroidota varied significantly between mossy biocrust rhizoid and different particle sizes of mossy biocrust sifting and sublayer soil (p < 0.05). Similarly, significant differences (p < 0.05) were observed in the mean proportions of Ascomycota, Basidiomycota, and Glomeromycota between mossy biocrust rhizoid and different particle sizes within the mossy biocrust sifting and sublayer soil. The complexity and connectivity of bacterial and fungal networks were higher in mossy biocrust rhizoid soil compared with different particle sizes within the mossy biocrust sifting and sublayer soil. Discussion: These results offer valuable insights to enhance our understanding of the involvement of mossy biocrust in the biogeochemical cycle of desert ecosystems.

Effective long-term sirolimus treatment in hypoxemia mainly due to intrapulmonary right-to-left shunt in a patient with multiple vascular anomalies.

Pulmonary arteriovenous malformations (PAVMs), particularly where feeding artery/arteries to PAVMs ≥ 3 mm can be treated with embolization. The treatment for hypoxemia resulting from multiple small or diffuse PAVMs remains unclear.We report a girl aged 5 years and 10 months presented with cyanosis and decreased activity after exercise (83-85% of pulse oxygen saturation, SpO2). She had 1 skin lesion on her face and 1 suspected hemangioma on her left upper extremity at birth and that gradually disappeared spontaneously. Physical examination revealed clubbed fingers, and abundant vascular networks on her back. Contrast-enhanced lung CT (slice thickness:1.25 mm) with vascular three-dimensional reconstruction and abdominal CT revealed increased bronchovascular bundles, increased diameter of the pulmonary artery and ascending aorta, and intrahepatic portosystemic venous shunts due to patent ductus venosus. Echocardiography revealed increased diameter of aortic and pulmonary artery. Transthoracic contrast echocardiography was highly positive (bubble appearing in the left ventricle after 5 cardiac cycles). Abdominal doppler ultrasound revealed hepatic-portal venous shunt. Magnetic resonance imaging, artery and vein of the brain revealed multiple malformations of venous sinuses. The patient received sirolimus for 2 years and 4 months. Her condition improved significantly. SpO2 gradually increased to 98%. Her finger clubbing gradually normalized.Our report implicates sirolimus might be a potential treatment option in persistent hypoxemia mainly due to intrapulmonary right-to-left shunt even small multiple or diffusive PAVMs in pediatric patients with multiple cutaneous and visceral vascular anomalies.

A neutralizing-protective supersite of human monoclonal antibodies for yellow fever virus.

The yellow fever virus (YFV) is a life-threatening human pathogen. Owing to the lack of available therapeutics, non-vaccinated individuals are at risk. Here, we isolated eight human monoclonal antibodies that neutralize YFV infection. Five recognized overlapping epitopes and exhibited potent neutralizing activity. Two (YD6 and YD73) were ultra-potent and conferred complete protection against the lethal challenge of YFV as both prophylactics and therapeutics in a mouse model. Crystal structures revealed that YD6 engaged the YFV envelope protein in both pre- and post-fusion states, suggesting viral inhibition by a "double-lock" mechanism. The recognition determinants for YD6 and YD73 are clustered at the premembrane (prM)-binding site. Notably, antibodies targeting this site were present in minute traces in YFV-infected individuals but contributed significantly to neutralization, suggesting a vulnerable supersite of YFV. We provide two promising candidates for immunotherapy against YFV, and the supersite represents an ideal target for epitope-based vaccine design.

A combination vaccine against SARS-CoV-2 and H1N1 influenza based on receptor binding domain trimerized by six-helix bundle fusion core.

BACKGROUND: Increasing severe morbidity and mortality by simultaneous or sequential infections with SARS-CoV-2 and influenza A viruses (IAV), especially in the elderly and obese patients, highlight the urgency of developing a combination vaccine against COVID-19 and influenza. METHODS: Self-assembling SARS-CoV-2 RBD-trimer and Influenza H1N1 HA1-trimer antigens were constructed, upon the stable fusion core in post-fusion conformation. Immunogenicity of SARS-CoV-2 RBD-trimer vaccine and H1N1 HA1-trimer antigens candidates were evaluated in mice. Protection efficacy of a combination vaccine candidate against SARS-CoV-2 and IAV challenge was identified using the K18-hACE2 mouse model. FINDINGS: Both the resultant RBD-trimer for SARS-CoV-2 and HA1-trimer for H1N1 influenza fully exposed receptor-binding motifs (RBM) or receptor-binding site (RBS). Two-dose RBD-trimer induced significantly higher binding and neutralizing antibody titers, and also a strong Th1/Th2 balanced cellular immune response in mice. Similarly, the HA1-trimer vaccine was confirmed to exhibit potent immunogenicity in mice. A combination vaccine candidate, composed of RBD-trimer and HA1-trimer, afforded high protection efficacy in mouse models against stringent lethal SARS-CoV-2 and homogenous H1N1 influenza co-infection, characterized by 100% survival rate. INTERPRETATION: Our results represent a proof of concept for a combined vaccine candidate based on trimerized receptor binding domain against co-epidemics of COVID-19 and influenza. FUNDING: This project was funded by the Strategic Priority Research Program of CAS (XDB29040201), the National Natural Science Foundation of China (81830050, 81901680, and 32070569) and China Postdoctoral Science Foundation (2021M703450).

Convex and Concave Model 3D Printing for Designing Right-side Bronchial Blocker for Infants.

It is technically challenging for pediatric anesthesiologists to use bronchial blocker (BB) to isolate the lungs of infants during thoracoscopic surgery. Further, BB currently sold in the market cannot match the anatomical characteristics of the infants, especially on the right main bronchus. It may easily cause poor exhaustion of the right upper lobe, which leads to interference with the thoracoscopic surgical field. The two dimensional reconstruction data of 124 normal infants' airways were extracted from the medical image database of Beijing Children's Hospital for statistical analysis. After using linear fitting and goodness-of-fit test, a good linear relationship was detected between infant age and various parameters related to aid in designing a new BB for infants (R2=0.502). According to the growth and development rate of infants, the DICOM files of airway CT scan of 7 infants aged 30, 60, 90, 120, 180, 270, and 360 days were selected to print non-transparent convex and transparent concave 3D models. The non-transparent convex model was precisely measured to obtain the important parameters for BB design infants only, to complete the design of BB, to generate the sample, and to verify the blocking effect of produced sample in transparent concave three-dimensional (3D) model.

Erratum to Application of magnetic resonance neurography in neonatal brachial plexus injury: A case report and literature review [Radiology Case Reports 17 (2022) 2859-2862].

[This corrects the article DOI: 10.1016/j.radcr.2022.04.017.].

Application of magnetic resonance neurography in neonatal brachial plexus injury: A case report and literature review.

Neonatal obstetric brachial plexus palsy is common in newborns with fetal macrosomia, especially those who are delivered vaginally with shoulder dystocia or breech delivery. The anatomical structure of brachial plexus in newborns is thin, and it is neither collinear nor coplanar in space; The location, the type and degree of neonatal brachial plexus injury need to be comprehensively judged by clinical history, neurological and imaging examination. Conventional MR imaging is not sufficient to diagnose brachial plexus injury. In this case report, we describe the clinical and imaging data of a newborn with brachial plexus injury diagnosed by the fat-suppressed T2-weighted sequence and MR myelography and confirmed by surgery. In addition, we review the related literature in an attempt to provide a better understanding of the principles and characteristics of neonatal brachial plexus injury diagnosed by magnetic resonance neurography.

Ethylene Promotes Expression of the Appressorium- and Pathogenicity-Related Genes via GPCR- and MAPK-Dependent Manners in Colletotrichum gloeosporioides.

Ethylene (ET) represents a signal that can be sensed by plant pathogenic fungi to accelerate their spore germination and subsequent infection. However, the molecular mechanisms of responses to ET in fungi remain largely unclear. In this study, Colletotrichum gloeosporioides was investigated via transcriptomic analysis to reveal the genes that account for the ET-regulated fungal development and virulence. The results showed that ET promoted genes encoding for fungal melanin biosynthesis enzymes, extracellular hydrolases, and appressorium-associated structure proteins at 4 h after treatment. When the germination lasted until 24 h, ET induced multiple appressoria from every single spore, but downregulated most of the genes. Loss of selected ET responsive genes encoding for scytalone dehydratase (CgSCD1) and cerato-platanin virulence protein (CgCP1) were unable to alter ET sensitivity of C. gloeosporioides in vitro but attenuated the influence of ET on pathogenicity. Knockout of the G-protein-coupled receptors CgGPCR3-1/2 and the MAPK signaling pathway components CgMK1 and CgSte11 resulted in reduced ET sensitivity. Taken together, this study in C. gloeosporioides reports that ET can cause transcription changes in a large set of genes, which are mainly responsible for appressorium development and virulence expression, and these processes are dependent on the GPCR and MAPK pathways.

Etesevimab in combination with JS026 neutralizing SARS-CoV-2 and its variants.

The neutralizing antibody is a potential therapeutic for the ongoing COVID-19 pandemic. As an antiviral agent, numerous mAbs recognize the epitopes that overlap with ACE2-binding sites in the SARS-CoV-2-RBD. Some studies have shown that residual changes on the spike protein can significantly decrease the efficiency of neutralizing antibodies. To address this issue, a therapeutic cocktail could be an effective countermeasure. In the present study, we isolated a fully human neutralizing antibody, JS026, from a convalescent patient. The comparative analysis revealed that JS026 binding to SARS-CoV-2-RBD mainly located between epitopes for class 2 and class 3 mAbs as opposed to that of class 1 (etesevimab) antibodies. A cocktail of etesevimab and JS026 increased neutralizing efficacy against both wild-type SARS-CoV-2 and the recent emergence of Alpha, Beta, Gamma, and Delta variants. JS026 and the cocktail reduced virus titers in the infected lungs of hACE2 transgenic mice and relieved pathological changes. These findings would benefit antibody-based therapeutic countermeasures in the treatment of COVID-19.

A broadly neutralizing humanized ACE2-targeting antibody against SARS-CoV-2 variants.

The successive emergences and accelerating spread of novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) lineages and evolved resistance to some ongoing clinical therapeutics increase the risks associated with the coronavirus disease 2019 (COVID-19) pandemic. An urgent intervention for broadly effective therapies to limit the morbidity and mortality of COVID-19 and future transmission events from SARS-related coronaviruses (SARSr-CoVs) is needed. Here, we isolate and humanize an angiotensin-converting enzyme-2 (ACE2)-blocking monoclonal antibody (MAb), named h11B11, which exhibits potent inhibitory activity against SARS-CoV and circulating global SARS-CoV-2 lineages. When administered therapeutically or prophylactically in the hACE2 mouse model, h11B11 alleviates and prevents SARS-CoV-2 replication and virus-induced pathological syndromes. No significant changes in blood pressure and hematology chemistry toxicology were observed after injections of multiple high dosages of h11B11 in cynomolgus monkeys. Analysis of the structures of the h11B11/ACE2 and receptor-binding domain (RBD)/ACE2 complexes shows hindrance and epitope competition of the MAb and RBD for the receptor. Together, these results suggest h11B11 as a potential therapeutic countermeasure against SARS-CoV, SARS-CoV-2, and escape variants.

Safety and immunogenicity of a recombinant tandem-repeat dimeric RBD-based protein subunit vaccine (ZF2001) against COVID-19 in adults: two randomised, double-blind, placebo-controlled, phase 1 and 2 trials.

BACKGROUND: Although several COVID-19 vaccines have been developed so far, they will not be sufficient to meet the global demand. Development of a wider range of vaccines, with different mechanisms of action, could help control the spread of SARS-CoV-2 globally. We developed a protein subunit vaccine against COVID-19 using a dimeric form of the receptor-binding domain (RBD) of the SARS-CoV-2 spike protein as the antigen. We aimed to assess the safety and immunogenicity of this vaccine, ZF2001, and determine the appropriate dose and schedule for an efficacy study. METHODS: We did two randomised, double-blind, placebo-controlled, phase 1 and phase 2 trials. Phase 1 was done at two university hospitals in Chongqing and Beijing, China, and phase 2 was done at the Hunan Provincial Center for Disease Control and Prevention in Xiangtan, China. Healthy adults aged 18-59 years, without a history of SARS-CoV or SARS-CoV-2 infection, an RT-PCR-positive test result for SARS-CoV-2, a history of contact with confirmed or suspected COVID-19 cases, and severe allergies to any component of the vaccine were eligible for enrolment. In phase 1, participants were randomly assigned (2:2:1) to receive three doses of the vaccine (25 µg or 50 µg) or placebo intramuscularly, 30 days apart. In phase 2, participants were randomly assigned (1:1:1:1:1:1) to receive the vaccine (25 µg or 50 µg) or placebo intramuscularly, 30 days apart, in either a two-dose schedule or a three-dose schedule. Investigators, participants, and the laboratory team were masked to group allocation. For phase 1, the primary outcome was safety, measured by the occurrence of adverse events and serious adverse events. For phase 2, the primary outcome was safety and immunogenicity (the seroconversion rate and the magnitude, in geometric mean titres [GMTs], of SARS-CoV-2-neutralising antibodies). Analyses were done on an intention-to-treat and per-protocol basis. These trials are registered with ClinicalTrials.gov (NCT04445194 and NCT04466085) and participant follow-up is ongoing. FINDINGS: Between June 22 and July 3, 2020, 50 participants were enrolled into the phase 1 trial and randomly assigned to receive three doses of placebo (n=10), the 25 µg vaccine (n=20), or the 50 µg vaccine (n=20). The mean age of participants was 32·6 (SD 9·4) years. Between July 12 and July 17, 2020, 900 participants were enrolled into the phase 2 trial and randomly assigned to receive two doses of placebo (n=150), 25 µg vaccine (n=150), or 50 µg vaccine (n=150), or three doses of placebo (n=150), 25 µg vaccine (n=150), or 50 µg vaccine (n=150). The mean age of participants was 43·5 (SD 9·2) years. In both phase 1 and phase 2, adverse events reported within 30 days after vaccination were mild or moderate (grade 1 or 2) in most cases (phase 1: six [60%] of ten participants in the placebo group, 14 [70%] of 20 in the 25 µg group, and 18 [90%] of 20 in the 50 µg group; phase 2: 37 [25%] of 150 in the two-dose placebo group, 43 [29%] of 150 in the two-dose 25 µg group, 50 [33%] of 150 in the two-dose 50 µg group, 47 [31%] of 150 in the three-dose placebo group, 72 [48%] of 150 in the three-dose 25 µg group, and 65 [43%] of 150 in the three-dose 50 µg group). In phase 1, two (10%) grade 3 or worse adverse events were reported in the 50 µg group. In phase 2, grade 3 or worse adverse events were reported by 18 participants (four [3%] in the two-dose 25 µg vaccine group, two [1%] in the two-dose 50 µg vaccine group, two [1%] in the three-dose placebo group, four [3%] in the three-dose 25 µg vaccine group, and six [4%] in the three-dose 50 µg vaccine group), and 11 were considered vaccine related (two [1%] in the two-dose 25 µg vaccine group, one [1%] in the two-dose 50 µg vaccine group, one [1%] in the three-dose placebo group, two [1%] in the three-dose 25 µg vaccine group, and five [3%] in the three-dose 50 µg vaccine group); seven participants reported serious adverse events (one [1%] in the two-dose 25 µg vaccine group, one [1%] in the two-dose 50 µg vaccine group, two [1%] in the three-dose placebo group, one [1%] in the three-dose 25 µg vaccine group, and two [1%] in the three-dose 50 µg vaccine group), but none was considered vaccine related. In phase 2, on the two-dose schedule, seroconversion rates of neutralising antibodies 14 days after the second dose were 76% (114 of 150 participants) in the 25 µg group and 72% (108 of 150) in the 50 µg group; on the three-dose schedule, seroconversion rates of neutralising antibodies 14 days after the third dose were 97% (143 of 148 participants) in the 25 µg group and 93% (138 of 148) in the 50 µg group. In the two-dose groups in phase 2, the SARS-CoV-2-neutralising GMTs 14 days after the second dose were 17·7 (95% CI 13·6-23·1) in the 25 µg group and 14·1 (10·8-18·3) in the 50 µg group. In the three-dose groups in phase 2, the SARS-CoV-2-neutralising GMTs 14 days after the third dose were 102·5 (95% CI 81·8-128·5) in the 25 µg group and 69·1 (53·0-90·0) in the 50 µg group. INTERPRETATION: The protein subunit vaccine ZF2001 appears to be well tolerated and immunogenic. The safety and immunogenicity data from the phase 1 and 2 trials support the use of the 25 µg dose in a three-dose schedule in an ongoing phase 3 trial for large-scale evaluation of ZF2001's safety and efficacy. FUNDING: National Program on Key Research Project of China, National Science and Technology Major Projects of Drug Discovery, Strategic Priority Research Program of the Chinese Academy of Sciences, and Anhui Zhifei Longcom Biopharmaceutical. TRANSLATION: For the Chinese translation of the abstract see Supplementary Materials section.

Diagnosis of double-chambered left ventricle using echocardiography.

Double-chambered left ventricle (DCLV) is a particularly rare congenital cardiovascular malformation that is difficult to diagnose. It is characterized by the subdivision of the left ventricle into two chambers by an abnormal septum or muscle band. Here, we report 12 patients with DCLV. Differential diagnoses of DCLV include four other cardiac diseases, diverticulum, aneurysm, hypertrophic cardiomyopathy, and left ventricular noncompaction. Echocardiography plays an important role in the diagnosis of this rare condition and in differentiating it from other diseases.

Left atrial appendage aneurysm in pediatrics.

Left atrial appendage aneurysm (LAAA) is a rare cardiac anomaly with potentially life-threatening complications of atrial tachyarrhythmias and systemic thromboembolism. It is often diagnosed incidentally and rarely during childhood. Echocardiography is considered the primary method of LAAA diagnosis; in particular, the subxiphoid view is more useful in pediatrics. Surgical intervention and drug management are recommended to prevent potentially lethal complications. Herein, we report five cases of patients with LAAA during infancy and childhood, caused by both congenital and acquired conditions. One patient underwent surgical resection through left lateral thoracotomy without cardiopulmonary bypass and another patient underwent drug management.

A human neutralizing antibody targets the receptor-binding site of SARS-CoV-2.

An outbreak of coronavirus disease 2019 (COVID-19)1-3, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)4, has spread globally. Countermeasures are needed to treat and prevent further dissemination of the virus. Here we report the isolation of two specific human monoclonal antibodies (termed CA1 and CB6) from a patient convalescing from COVID-19. CA1 and CB6 demonstrated potent SARS-CoV-2-specific neutralization activity in vitro. In addition, CB6 inhibited infection with SARS-CoV-2 in rhesus monkeys in both prophylactic and treatment settings. We also performed structural studies, which revealed that CB6 recognizes an epitope that overlaps with angiotensin-converting enzyme 2 (ACE2)-binding sites in the SARS-CoV-2 receptor-binding domain, and thereby interferes with virus-receptor interactions by both steric hindrance and direct competition for interface residues. Our results suggest that CB6 deserves further study as a candidate for translation to the clinic.

A Matrix Information-Geometric Method for Change-Point Detection of Rigid Body Motion.

A matrix information-geometric method was developed to detect the change-points of rigid body motions. Note that the set of all rigid body motions is the special Euclidean group S E ( 3 ) , so the Riemannian mean based on the Lie group structures of S E ( 3 ) reflects the characteristics of change-points. Once a change-point occurs, the distance between the current point and the Riemannian mean of its neighbor points should be a local maximum. A gradient descent algorithm is proposed to calculate the Riemannian mean. Using the Baker-Campbell-Hausdorff formula, the first-order approximation of the Riemannian mean is taken as the initial value of the iterative procedure. The performance of our method was evaluated by numerical examples and manipulator experiments.

[Imaging findings of bone infarction in children with systemic lupus erythematosus].

OBJECTIVE: To investigate diagnostic value of MRI, X ray and CT for bone infarction in children with systemic lupus erythematosus. METHODS: Eleven systemic lupus erythematosus children with bone infarction were retrospectively analyzed from January 2015 to January 2017 , and tested by MRI, X-ray and CT. Among them, including 1 male and 10 females aged from 6 to 16 years old with an average of 13 years old. All patients were detected by MRI, 9 patients were detected by X-ray and 3 patients were detected by CT, imaging findings were analyzed. RESULTS: The location of bone infarction involved 60 sits, 30 sites located on metaphyseal-diaphyseal region, 8 located on patella, 21 located on epiphysis, and 1 located on talus. Focus of 11 patients were detected by MRI, the main manifestation showed geographic change, long T1 and T2 signal could seen around focus, and showed double ring sign and three ring sign; 5 of 9 patients by X-ray examination detected focus;2 of 3 patients by CT examination detected focus. No abnormity seen at early stage by X-ray and CT examination, and low density focus around harden edge at chronic stage. CONCLUSIONS: MRI could display bone fracture at early stage, X-ray and CT could only display lesion at chronic stage, MRI is the most effective method in diagnosing bone infarction.