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Background The recurrence of positive SARS-CoV-2 RT-PCR is frequently found in discharged COVID-19 patients but its clinical significance remains unclear. The potential cause, clinical characteristics and infectiousness of the recurrent positive RT-PCR patients need to be answered. Methods A single-centered, retrospective study of 51 discharged COVID-19 patients was carried out at a designated hospital for COVID-19. The demographic data, clinical records and laboratory findings of 25 patients with recurrent positive RT-PCR from hospitalization to follow-up were collected and compared to 26 patients with negative RT-PCR discharged regularly during the same period. Discharged patients’ family members and close contacts were also interviewed by telephone to evaluate patients’ potential infectiousness. Results The titer of both IgG and IgM antibodies was significantly lower (p = 0.027, p = 0.011) in patients with recurrent positive RT-PCR. Median duration of viral shedding significantly prolonged in patients with recurrent positive RT-PCR (36.0 days vs 9.0 days, p = 0.000). There was no significant difference in demographic features, clinical features, lymphocyte subsets count and inflammatory cytokines levels between the two groups of patients. No fatal case was noted in two groups. As of the last day of follow-up, none of the discharged patients’ family members or close contact developed any symptoms of COVID-19. Conclusions Patients with low levels of IgG and IgM are more likely to have recurrent positive SARS-CoV-2 RT-PCR results and lead to a prolonged viral shedding. The recurrent positive of SARS-CoV-2 RT-PCR may not indicate the recurrence or aggravation of COVID-19. The detection of SARS-CoV-2 by RT-PCR in the patients recovered from COVID-19 is not necessarily correlated with the ability of transmission.

Solar-thermal evaporation is a promising technology for energy-efficient desalination, but salt accumulation on solar absorbers and system longevity are the major challenges that hinder its widespread application. In this study, we present a sustainable Janus wood evaporator that overcomes these challenges and achieves a record-high evaporation efficiencies in hypersaline water, one of the most difficult water sources to treat via desalination. The Janus wood evaporator has asymmetric surface wettability, where the top layer acts as a hydrophobic solar absorber with water blockage and salt resistance, while the bottom hydrophilic wood layer allows for rapid water replenishment and superior thermal insulation. An evaporation efficiency of 82.0% is achieved for 20% NaCl solution under 1 sun, and persistent salt-resistance is observed during a 10-cycle long-term test. To ensure the environmental impact of the Janus wood evaporator, for the first time, a life cycle assessment (LCA) is conducted to compare this Janus wood evaporator with the emerging Janus evaporators, indicating a functional and more sustainable opportunity for off-grid desalination and humanitarian efforts.

Transbronchial cryobiopsy (TBCB) is a technique to obtain frozen samples of lung tissue from the distal bronchioles, in which the tissue surrounding the tip of a cryoprobe inserted through the bronchoscope is frozen with a rapid freezing process and abruptly pulled away from adherent tissue. The advantages of TBCB are improved diagnostic yield, reduced trauma, large and high-quality specimens, potentially decreased complications, and lower cost in comparison to surgical lung biopsy (SLB). TBCB is mainly used for the etiological diagnosis of diffuse parenchymal lung diseases (DPLD) (1,2). Additionally, it can be used for biopsy of peripheral lung lesions. TBCB has been widely used as a new diagnostic tool in Europe since 2009 (1), and has been used in some highly specialized interventional centers in China since 2015 (3). However, the procedure of TBCB has not been standardized. There are still disagreements among pulmonologists internationally and in China regarding operation methods, biopsy sites, number of biopsy specimens, types of frozen probes, freezing time and specimen handling, and there is urgent need for procedural standardization of TBCB for effectiveness and safety. This work is an evidence- and expert-based consensus on the procedure and technique of TBCB, which is a collaborative effort of the Working Committee on Interventional Pulmonology, Respiratory Physicians’ Branch of Chinese Medical Doctor Association, Committee of Interventional Pulmonology, Chinese Society for Tuberculosis, Chinese Medical Association, and the Chinese Western Association of Interventional Pulmonology. We hope it will contribute to the transition of the etiologic diagnosis of DPLD from the clinico-radiologic (CR) model to the clinico-radiologic-pathologic (CRP) model, which hopefully will increase the rate of etiologic diagnosis of DPLD, and improves the effectiveness, safety and standardization of the procedure and technique of TBCB to ensure diagnostic yield.

BACKGROUND Post-tuberculosis bronchomalacia (PTBM) is one of the main conditions occurring in patients after tracheobronchial tuberculosis (TBTB), and is also associated with the recurrence of symptoms. The present study aimed to investigate the predictors of PTBM in patients who had been undergoing appropriate TB treatment. MATERIAL AND METHODS Clinical data of 104 patients with symptomatic airway stenosis after TBTB between January 01, 2019 and June 31, 2020 were recorded and analyzed. The association between baseline clinical characteristics, laboratory results, and PTBM was calculated with logistical regression. The time from onset of bronchoscopic intervention was examined by Kaplan-Meier estimates; differences between the 2 groups were tested by the log-rank test. RESULTS Fifty-seven patients (54.81%) had PTBM. In the multivariate logistical analysis, the left main bronchus stenosis lesion (odds ratio [OR]=3.763), neutrophil (NEUT) count (OR=1.527), and platelet (PLT) (OR=1.010) count were predictors of PTBM. During follow-up, patients with BM had a significantly longer duration from onset of bronchoscopic intervention than patients without BM (hazard ratio=2.412, P0.0001). Further, all patients needing long-term bronchoscopic intervention therapy were subsequently identified as having PTBM. Additionally, blood PLT counts were significantly decreased to normal levels in the non-BM group (P0.05), but not in the BM group (P0.05). CONCLUSIONS PTBM is most likely to occur in the left main bronchus. The inflammatory and immune responses associated with NEUT and PLT may represent therapeutic targets of PTBM. Our study is the first to report that decreased blood PLT count has the potential to monitor the treatment response.

Waterborne diseases related to unsafe water are still major threats to public health in some developing countries and rural areas. Providing affordable and safe drinking water globally remains a great challenge in the coming decades. In this study, we develop a high-throughput and conductive silver nanowire (AgNW)-modified composite filter via depositing thin and ultralong AgNWs on a macroporous substrate. An electrochemical filtration cell (EFC) equipped with the composite filter achieves controllable Ag+ release at a μg L-1 level and superior bacterial inactivation performance (>6-log inactivation efficiency) with an operation voltage of only 1 V at a high flux of 100 m3 h-1 m-2. Under such operation conditions, each composite filter (effective area: 0.79 cm2) can treat at least 750 mL of the bacterial suspension (∼107 CFU mL-1 of Escherichia coli) with a low effluent Ag+ concentration below 50 μg L-1 and almost negligible energy consumption of only ∼70 J m-3.

Objective: To explore the effect of an evidence-based bundled care model in patients with dysphagia after severe traumatic brain injury (TBI). Methods: This is a prospective randomized controlled study. A total of 60 patients with dysphagia after severe TBI (traumatic brain injury) admitted to the Department of Rehabilitation Medicine were selected and randomly divided into the test group (n=30) and the control group (n=30). Patients in the control group received routine care in the Department of Rehabilitation Medicine, while patients in the test group received evidence-based bundled care on the basis of the treatment of the control group. The improvement of swallowing function (dye test in comatose patients), oral hygiene, and nutritional risk was assessed in both groups. The incidence of adverse events such as aspiration and aspiration pneumonia, as well as the length and costs of hospitalization were compared between the two groups. Results: Compared with patients in the control group, swallowing function of patients in the test group was significantly improved after the care (P

Non-invasive strategies for monitoring post-tuberculosis (TB) tracheobronchial stenosis (PTTS) are clinically important but currently lacking. Transforming growth factor-β1 (TGF-β1) and procollagen type I N-propeptide (PINP) have been identified as markers of fibrosis. The present study aimed to investigate the clinical significance of serum TGF-β1 and PINP in PTTS. Serum samples were collected from 119 patients with tracheobronchial TB after the condition was treated for at least 6 months (59 patients with airway stenosis and 60 patients with no stenosis). Serum TGF-β1 and PINP levels were measured using ELISA and compared between the groups. Relationships between serum TGF-β1 and PINP levels and clinical characteristics, interventional bronchoscopy and outcomes of airway stenosis were analysed. The correlation between TGF-β1 and PINP, and their diagnostic efficacy for airway stenosis were also analysed. The TGF-β1 and PINP levels in the airway stenosis group were higher than those in the non-stenosis group. Furthermore, airway stenosis with atelectasis or mucus plugging was associated with higher TGF-β1 levels, and airway stenosis with atelectasis, mucus plugging, right main bronchus stenosis or severe airway tracheal stenosis was associated with higher PINP levels. In addition, TGF-β1 and PINP levels increased after interventional bronchoscopy therapy and airway stenosis with recurrent stenosis was associated with higher baseline levels of both markers. Finally, TGF-β1 levels were positively correlated with PINP levels in patients with airway stenosis. The area under the receiver operating characteristic curve of TGF-β1 and PINP for distinguishing airway stenosis from non-stenosis cases was 0.824 (95% CI: 0.748-0.900) and 0.863 (95% CI: 0.796-0.930), respectively. Therefore, TGF-β1 and PINP are potential biomarkers that may be useful for diagnosing and monitoring PTTS.

Speckle-type POZ protein (SPOP), a novel cancer- associated protein, was previously reported to function as a tumor suppressor or promoter in different malignant tumors. This research aims to investigate the biological functions and underlying molecular mechanisms of SPOP in choriocarcinoma. Our analysis of patient tissues and cell lines showed significantly decreased SPOP expression and highly expressed Nuclear DNA helicase II and RNA helicase A (DHX9), both of them are mainly located into the nucleus. Induction or depletion of endogenous SPOP with a lentivirus-based system correspondingly suppressed or promoted migration and invasion of choriocarcinoma cells. Mechanistically, we found that SPOP bound to DHX9 and induced the ubiquitination and degradation of DHX9 by recognizing a typical SPOP-binding motif in DHX9. SPOP-DHX9 interaction was demonstrated to play a critical role in regulating migration and invasion abilities of choriocarcinoma cells, the promotion of mobility ability in knocking down SPOP was partly counteracted by transfection with siRNA against DHX9. Taken together, our results suggest that SPOP suppresses migration and invasion of choriocarcinoma by promoting the ubiquitination and subsequent degradation of DHX9, which identifies the SPOP-DHX9 interaction may serve as a potential therapeutic target against choriocarcinoma.

Background: Severe acute respiratory syndrome coronavirus 2(SARS-CoV-2), a novel betacoronavirus, has caused an outburst of pneumonia cases in Wuhan, China. We report the production of specific IgM and IgG antibodies after the infection of SARS-CoV-2 and its implication for the diagnosis, pathology and the course of the disease as well as the recurrence of positive nucleic acid tests after discharge. Methods: Test results for SARS-CoV-2 IgM and IgG antibodies of 221 confirmed COVID-19 patients were retrospectively examined, and their clinical data were collected and analyzed based on various subgroups. SARS-CoV-2 IgM and IgG antibodies were determined with the chemiluminescence method. Findings: The concentration (S/CO) of SARS-CoV-2 IgM and IgG antibodies peaked on day 19-21 after symptom onset, with a median of 17.38 (IQR 4·39-36·4) for IgM and 5·59 (IQR 0·73-13·65) for IgG. Detection rates reached highest on day 16-18 and day 19-21 for IgM and IgG, which were 73·6% and 98·6%, respectively, with significantly higher concentration of IgG in critically ill patients than in those with mild to moderate disease (P=0·027). The concentration of the antibodies on day 16-21 is not correlated with the course or outcome of the disease (Spearman r 0·05). Nasopharyngeal swabs revealed positive SARS-CoV-2 RNA in up to 52.7% of recovered patients after discharge, whose IgG proved to be significantly lower than that of those with negative RNA results (P = 0·009). IgG and IgM were tested twice within 14 days after discharge with a 7-day interval, and the second testing of these antibodies displayed a decrease in concentration of 21·2% (IQR, 11·2%，34·48%) for IgG and 23.05% (IQR, -27·96%，46·13%) for IgM, without statistical significance between the patients with re-detectable positive RNA results and those with negative RNA results after discharge; however, those with positive results experienced a count decrease in lymphocyte subsets. Interpretation: The concentration of SARS-CoV-2 IgM and IgG antibodies peaked on day 19-21 after symptom onset, and antibody testing on day 16-21 is associated with increased detection rates, but the antibody concentration does not affect the course and outcome of the infection. Recovering patients with re-detectable positive SARS-CoV-2 RNA displayed lower concentration of IgG, but the downward trend of IgG during recovery indicated its limited duration of protection, and the protective effect of IgG remains to be investigated. Funding Statement: This work is funded by Chongqing Education Board “new coronavirus infection and prevention” emergency scientific research project (KYYJ202006). Chongqing Science and Technology Bureau “new crown pneumonia epidemic emergency science and technology special” the fourth batch of projects. Famous teacher project of Chongqing talent plan. Declaration of Interests: The authors declare no competing interests. Ethics Approval Statement: This study was approved by the Medical Ethical Committee of the First Affiliated Hospital of Chongqing Medical University (approval number 20200601). Due to the special reasons of the epidemic, the patients’ informed consent was not obtained.

Primary mucosa-associated lymphoid tissue (MALT) lymphoma of the trachea is very rare and is easily misdiagnosed as a bronchogenic carcinoma or benign tracheal tumor. Here, we report a clinical case where a new clinical approach involving a water-jet hybrid knife was employed in the diagnosis and treatment of primary tracheal MALT lymphoma.

BACKGROUND Extubation failure (EF) is high in patients on mechanical ventilation for more than 7 days. However, strategies to prevent EF in this population are lacking. AIMS To evaluate the efficacy of preventive use of noninvasive ventilation in patients on mechanical ventilation for more than 7 days. METHODS We performed a retrospective study in an intensive care unit of a teaching hospital. We enrolled patients who received mechanical ventilation for more than 7 days and successfully completed a weaning trial. After extubation, patients who immediately received non-invasive ventilation (NIV) were classified as the NIV group, and those who received conventional oxygenation therapy only were classified as the usual care group. RESULTS We enrolled 95 patients in the NIV group and 61 patients in the usual care group. NIV is associated with reduced risk of EF compared to usual care both 72 h following extubation (11.6% vs 32.8%, P

Background: Transbronchial cryobiopsy (TBCB), a novel way of obtaining a specimen of lung tissue using a flexible cryoprobe, can obtain large lung biopsies without crush artifacts. The freezing time of TBCB was empirically selected from 3 to 7 s in the previous studies. However, no consensus has yet been reached regarding the optimal freezing time used in TBCB. Objectives: The primary endpoint was biopsy size in different freezing times. The secondary endpoints included sample histological quality, diagnostic confidence, and complications in different freezing times. Methods: Patients who were suspected of DPLD requiring histopathological examination for further evaluation were enrolled in this study. Distinct biopsies were obtained by using different freezing times increased from 3 to 6 s sequentially. Samples were reviewed by 2 external expert pathologists. Results: A total of 33 patients were enrolled, and 143 transbronchial cryobiopsies were taken in this trial. An average of 4.33 samples were taken from each patient. The mean biopsy size of different freezing times from 3 to 6 s was 9.10 ± 4.37, 13.23 ± 5.83, 16.26 ± 5.67, and 18.83 ± 7.50 mm2, respectively. A strong correlation between freezing time and biopsy size was observed (r = 0.99, p < 0.01). Statistically significant difference of biopsy size was detected in the freezing time of 3 s versus 4 s (p < 0.01) and 4 s versus 5 s (p = 0.02), but not in the freezing time of 5 s versus 6 s (p = 0.10). Overall bleeding in different freezing times from 3 to 6 s was 53.33%, 67.50%, 89.47%, and 77.14%, respectively. A significantly higher overall bleeding was observed when the freezing time exceeded 4 s (RR = 1.67, p < 0.01). Pneumothorax occurred in 4 cases (12.12%). One lethal case (3.03%) was noted 25 days after TBCB. Lung parenchyma was preserved well in all cryobiopsy samples. Thirty-one (93.94%) patients’ histopathological findings were identified as sufficient to establish a CRP diagnosis. There was no statistical difference in diagnostic confidence between different freezing times. Conclusion: A longer freezing time was associated with a larger size of the biopsy sample but a higher risk of bleeding. The optimal transbronchial cryobiopsy freezing time is 3–4 s, which is easily achievable and provides an adequate biopsy size whilst creating a safety threshold from complications.

Background: Gly307Ser (rs763361) polymorphism in Cluster of Differentiation 226 (CD226) gene has been implicated in susceptibility to autoimmune diseases (ADs) with controversial results. This study aimed to conduct a meta-analysis for examining the relationship between CD226 rs763361 polymorphism and ADs risk. Methods: a literature search was performed to identify relevant studies published in Embase, PubMed, Wanfang, and China National Knowledge Infrastructure. In the most appropriate genetic models, pooled odds ratio (OR) with 95% confidence interval (CI) was calculated for evaluating the strength of the associations. Besides standard meta-analysis, cumulative meta-analysis was also conducted to assess the trend in OR over time. Also, we performed subgroup and sensitivity analysis, and checked for the heterogeneity and publication bias. Results: Twenty-nine reports with 51 independent studies, comprising 18157 cases and 29904 controls, were enrolled in this meta-analysis. Among overall and various ethnic populations (Europeans, Asians, Africans, and South Americans), CD226 rs763361 polymorphism was significantly associated with ADs susceptibility; in the subgroup analysis by disease type, rs763361 polymorphism revealed significant associations with the risk of RA, SLE, T1D, and MS. The sensitivity analysis and cumulative meta-analysis confirmed the stability and robustness of these significant results. However, no evidence of stable significant association emerged in the subgroup analysis of SSc. Conclusion: These findings demonstrate that CD226 rs763361 polymorphism confers susceptibility to ADs in the overall population, Europeans, Asians, Africans, and South Americans. rs763361 polymorphism in CD226 gene may be a potential susceptible predictor of ADs especially RA, SLE, T1D, and MS.

Diisobutylaluminum hydride is utilized to reduce pentacene-6,13-diones to the corresponding diols, useful precursors to functionalized pentacenes. This pathway is mild and efficient, and produces the cis-diols as major products. Further, we found the cis-diols adopt endo conformation, which cannot flip to the exo conformation under ambient conditions. Due to the cis and endo orientation, the cis-diols can be potential bidentates in catalysis, molecular propellers, and optoelectronic devices.

Franck−Condon coupling to the electronic structure of anthracene silane isomer complexes self-assembled on a silicon oxide surface has been measured by high-resolution photoelectron emission spectroscopy. Our results are in strong agreement with theoretical semiempirical calculations and gas phase measurements. The Franck−Condon vibronic fine structure observed in the high resolution photoemission spectra exhibits a strong dependence on the isomer, in particular, the anthracene functional group orientation with respect to the surface normal.

Single molecular layers of 2-(4-pyridylethyl)triethoxysilane have been deposited on native oxide surfaces of silicon, with the triethoxysilylethyl groups towards the silicon oxide interface and pyridine at the surface. It is possible to “shave” or mechanically break the molecular bonds at the alkoxy-silane (Si–C) bond using scanning atomic force microscope, leaving large swaths of surface area cut to a depth of 0.64 ± 0.06 nm, exposing the silicon of the alkoxy-silane ligand. Mechanical cleavage of the pyridine ligand alone is also possible, but more difficult to control selectively.

Stable, soluble ethynylated derivatives of pentacene (9a-c) were synthesized, and the ethynyl moieties on the terminal rings were used to tune the electronic properties of these compounds. Their oxidation potentials are higher and their reduction potentials are lower than those of pentacene. The HOMO-LUMO gaps are among the lowest reported for pentacene derivatives.

We report here a simple pathway to thermally assemble acene-based molecules into large crystals without modification of their chemical structures. Differential scanning calorimetry was used to characterize properly thermal events occurring during successive heating and cooling processes. More interestingly, observations by means of polarized light microscopy (POM) revealed that a spontaneous formation of screw dislocations within crystals during the isothermal treatment triggered a structural reorganization by forming large and well-defined spiral architectures. After this reorganization, new crystals showed an excellent ordering in both vertical and horizontal directions. Due to the richness in pi-electrons of acene-based molecules, we expect this work of importance to organic electronics, especially in the design of new molecular building blocks and investigation of their assembly into sophisticated supramolecular structures.

Energy absorption or dissipation from thin fi lms is increasingly demanded by civil and military applications. [ 1 ] And aluminum is probably the most well-known material that can absorb signifi cant amount of mechanic energy as thin fi lms. [ 2–4 ] Staircaselike loading and sharp unloading curves were revealed by nanoindentation, which were attributed to nucleation and glide of large number of dislocations. [ 5 ] Certainly, when great amount of these nanometer scale dislocations are made available in organic thin fi lms, they offer unmatched advantages including unlimited variability and processing ease. [ 3 ] While few studies were steered toward molecularly engineering an aluminum-like material, a simple mixing of fi brous(1D) or laminar-like (2D) fi llers within a bulk material could deliver a composite with signifi cant energy absorption. [ 6 ] To name a few, these include carbon fi ber/PEEK, [ 7–9 ] carbon fi ber/epoxy, [ 10 , 11 ] and glass cloth/ epoxy. [ 12 ] Central to the success of these polymer-based composites is their much increased fl exibility. Under external impact, the composites dissipate energies via mechanisms, such as structure buckling, interface cracking, delamination, or even laminar fragmentation. [ 6 ] Unfortunately, when such a macroscopic structure is condensed into a thin fi lm, the absence of bulk deformation in a confi ned space cannot generate enough response. Hence, it is desirable to have a solid, lightweight counterpart to aluminum thin fi lm and engineer dislocations therein for superior energy absorption. In this communication, we address this need by varying interfaces in supramolecules. [ 13 , 14 ] Over the past years, extensive studies on these well-ordered nanomaterials focused on modifying building

The packing of electronic molecules into planar structures and an ensured pi-pi interaction within the plane are preferred for efficient organic transistors. Thin films of organic electronics are exemplar, but the widely adopted molecular design and associated fabrication lead to limited ordering in multistack construction motifs. Here we demonstrate self-assembled nanolayers of organic molecules having potential electronic utility using an amphiphilic silane as a building block. Unlike a cross-linked (tetrahedral) configuration found in conventional siloxane networks, a linear polymer chain is produced following silane polycondensation. As a result, hydrophobic branches plus a noncovalent pi-pi interlocking between the molecules promote planar packing and continuous stacking along the surface normal. In contrast to conventional pi-pi stacking or hydrogen bonding pathways in a fibrous construct, multistacked nanolayers with coexisting pi-pi and herringbone interlocking can provide unmatched properties and processing convenience in molecular electronics.

Controlled self-assembly of polar aromatic silane leads to the formation of well-ordered lamellar structures. Graphite-like features are clearly visible with a scanning electron microscope (SEM). In addition, X-ray diffraction (XRD) patterns suggest a d spacing of 14.28 A along the z-axis and 4.42 A in the xy plane, which all agree with theoretical modeling. Constructing multistacks of silane molecules with a high degree of ordering is a daunting task. Amorphous monolayers are frequently reported. Aggravated van der Waals interaction, pi-pi electron overlapping, and solvophobic interactions can all lead to the formation of multistacks. The importance of a dipole to the ordered stacking is essentially unknown. This work suggests that a strong dipole-dipole interaction can be another important driving force in forming lamellar structures. The resulting large electrostatic interactions between the dipole and water provide an excellent thermal stability for these lamellas up to 350 degrees C. Organized, layered structures with a permanent dipole can be used in piezoelectric devices or as active surfaces to bind polar molecules, such as toxic gas, methanol, or DNA.