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1.
Front Microbiol ; 13: 860458, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35572674

RESUMO

There is an urgent call for contingency planning with effective and eco-friendly oil spill cleanup responses. In situ burning, if properly applied, could greatly mitigate oil in water and minimize the adverse environmental impacts of the spilled oil. Chemical herders have been commonly used along with in situ burning to increase the thickness of spilled oil at sea and facilitate combustion. These chemical surfactant-based agents can be applied to the edges of the oil slick and increase its thickness by reducing the water-oil interfacial tension. Biosurfactants have recently been developed as the next generation of herds with a smaller environmental footprint. In this study, the biosurfactant produced by Rhodococcus erythropolis M25 was evaluated and demonstrated as an effective herding agent. The impact of environmental and operational factors (e.g., temperature, herder dose, spilled oil amount, water salinity, and operation location) on its performance was investigated. A five-factor fractional design was applied to examine the importance of these factors and their impact on herding effectiveness and efficiency. The results of this study showed that higher temperature and a higher dose of herder could result in an increased oil slick thickness changing rate. Differences in water salinity at the same temperature led to the same trend, that is, the herding process effectively goes up with increasing herder-oil ratio (HOR). Further large-scale testing needs to be conducted for evaluating the applicability of the developed bioherder in the field.

2.
Cell Death Discov ; 8(1): 261, 2022 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-35568705

RESUMO

Triple-negative breast cancer (TNBC) is a molecular subtype with an unfavorable prognosis, and metastasis is the main reason for the failure of clinical treatment. However, the expression profile and regulatory function of circRNAs in TNBC progression are not fully understood. Herein, we performed high-throughput RNA-seq in paired breast cancer tissues and adjacent normal tissues and discovered a novel circRNA, circEIF3H, which was upregulated in breast cancer tissues. Large cohort survival analysis confirmed the association between high circEIF3H expression and poor prognosis of TNBC, indicating the vital function of circEIF3H in TNBC progression. Then we conducted both in vitro and in vivo experiments which illustrated that circEIF3H was essential for TNBC proliferation and metastasis. Further experiments showed that circEIF3H did not function as a microRNA sponge as in the most well-established pathway, but as a scaffold for IGF2BP2 and HuR to regulate the mRNA stability of HSPD1, RBM8A, and G3BP1. Our findings provide insight into a novel circRNA, circEIF3H, with significant cancer-promoting function via serving as a scaffold for IGF2BP2/HuR. These results identified circEIF3H as a potential target for developing individualized therapy of TNBC in the approaching future.

3.
Phytomedicine ; 101: 154105, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35490492

RESUMO

BACKGROUND: Chemotherapy drugs especially anthracyclines are widely used in the treatment of hematological malignancies and solid tumors. However, their clinical application is limited by dose-dependent and irreversible heart injury, which increases the risk of congestive heart failure and heart-related mortality. PURPOSE: This study aims to investigate the effect and mechanism of the natural flavonoid isoorientin (ISO) combined with doxorubicin (DOX) on the proliferation of tumor cells and improve the survival rate of DOX-injured cardiomyocytes. STUDY DESIGN/METHODS: Cardiomyocyte H9c2 and a variety of tumor cells were used to evaluate the protective effect of ISO on DOX-induced myocardial injury and enhance the anticancer effects of DOX. DOX chemotherapy-injured mice were used to evaluate the cardioprotective effect of ISO. RESULTS: The antiproliferation of DOX on Hela, HepG2, HT-29, and A549 cells could be increased synergistically when cotreated with ISO in vitro. ISO could also improve the survival rate of DOX-injured cardiomyocytes by reducing reactive oxygen species, maintaining mitochondrial function, and inhibiting apoptosis. In mice receiving DOX, a protective effect on myocardial tissue, which was reflected by improved survival state of mice receiving chemotherapy, was observed. The ECG, myocardial zymogram data, HE staining, and TEM observation of myocardial tissue sections showed that ISO had a dose-dependent protective effect on the mouse hearts injured by DOX. Network pharmacology and cardiomyocyte proteomics were used to seek for related target proteins to reveal the protective mechanism of ISO on mouse models, and some potential targets (including caspase-3, EGFR, MAPK1, ESR1, CDC42, STAT1, JAK2, LCK, and CDK2) were generated. Western blotting was further used to verify that ISO upregulated Nrf2 and TGF-ß3 by downregulating the phosphorylation levels of JNK and p38 proteins on the MAPK pathway and the Akt and Stat3 expression levels. The downregulation of cleaved caspase-3 and upregulation of Bcl-xl by ISO further confirmed its inhibition on caspase-dependent cardiomyocyte apoptosis. CONCLUSION: ISO could be a potential synergistic anticancer agent with a favorable property of reducing the cardiotoxicity for DOX, and the effect mechanism could refer to the inhibition of ISO on MAPK and caspase-dependent apoptosis pathways.

4.
Natl Sci Rev ; 9(4): nwab163, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35530433

RESUMO

Behavioral plasticity and the underlying neuronal plasticity represent a fundamental capacity of animals to cope with environmental stimuli. Behavioral plasticity is controlled by complex molecular networks that act under different layers of regulation. While various molecules have been found to be involved in the regulation of plastic behaviors across species, less is known about how organisms orchestrate the activity of these molecules as part of a coherent behavioral response to varying environments. Here we discover a mechanism for the regulation of animal behavioral plasticity involving molecular sulfation in the brain, a modification of substrate molecules by sulfotransferase (ST)-catalyzed addition of a sulfonate group (SO3) from an obligate donor, 3'-phosphoadenosine 5'-phosphosulfate (PAPS) to the substrates. We investigated aggregation behaviors of migratory locusts, which are well-known for extreme phase change plasticity triggered by population density. The processes of PAPS biosynthesis acted efficiently on induction of locust behavioral transition: Inhibition of PAPS synthesis solicited a behavioral shift from gregarious to solitarious states; external PAPS dosage, by contrast, promoted aggregation in solitarious locusts. Genetic or pharmacological intervention in the sulfation catalyzation resulted into pronounced solitarizing effects. Analysis of substrate-specific STs suggests a widespread involvement of sulfated neurotransmitters in the behavioral response. Dopamine in the brain was finally identified to be actively sulfate conjugated, and the sulfate conjugation enhanced the free DA-mediated behavioral aggregation. Similar results in Caenorhabditis elegans and mice indicate that sulfation may be involved more broadly in the modulation of animal aggregation. These findings reveal a general mechanism that effectively regulates animal social-like behavioral plasticity, possibly through sulfation-mediated modification of neural networks.

5.
Eur J Clin Pharmacol ; 2022 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-35536394

RESUMO

PURPOSE: Intracellular exposure of tacrolimus (TAC) may be a better marker of therapeutic effect than whole blood exposure. We aimed to evaluate the influence of genetic polymorphism on the pharmacokinetics of TAC in peripheral blood mononuclear cells (PBMCs) and develop limited sampling strategy (LSS) models to estimate the area under the curve (AUC0-12h) in the PBMC of Chinese renal transplant patients. METHODS: Ten blood samples of each of the 23 renal transplant patients were collected 0-12h after 14 (10-18) days of TAC administration. PBMCs were separated and quantified. The TAC level in PBMCs was determined, and pharmacokinetic parameters were estimated by noncompartmental study. The AUC0-12h of TAC in whole blood was estimated by Bayesian approach based on a population pharmacokinetic model established in 65 renal transplant patients. The influence of CYP3A5 and ABCB1 genotypes on exposure was estimated. By applying multiple stepwise linear regression analysis, LSS equations for TAC AUC0-12h in the PMBC of renal transplant patients were established, and the bias and precision of various equations were identified and compared. RESULTS: We found a modest correlation between TAC exposure in whole blood and PBMC (r2 = 0.5260). Patients with the CYP3A5 6986GG genotype had a higher AUC0-12h in PBMCs than those with the 6986 AA or GA genotype (P = 0.026). Conversely, patients with the ABCB1 3435TT genotype had a higher AUC0-12h in PBMC than those with the 3435 CC and CT genotypes (P = 0.046). LSS models with 1-4 blood time points were established (r2 = 0.570-0.989). The best model for predicting TAC AUC0-12h was C2-C4-C6-C10 (r2 = 0.989). The model with C0.5-C6 (r2 = 0.849) can be used for outpatients who need monitoring to be performed in a short period. CONCLUSIONS: The CYP3A5 and ABCB1 genotypes impact TAC exposure in PBMCs, which may further alter the effects of TAC. The LSS model consisting of 2-4 time points is an effective approach for estimating full TAC AUC0-12h in Chinese renal transplant patients. This approach may provide convenience and the possibility for clinical monitoring of TAC intracellular exposure.

6.
Ying Yong Sheng Tai Xue Bao ; 33(4): 1003-1011, 2022 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-35543053

RESUMO

We examined the effects of Spartina alterniflora invasion on phosphorus forms of marsh soils, based on the method of space-for-time substitution by selecting S. alterniflora marshes with different invasion years (SA1, 5-6 years; SA2, 8-10 years; and SA3, 12-14 years) in Shanyutan of the Minjiang River estuary. The results showed that in marsh soils of different invasion years, the proportion of hardly decomposable phosphorus (HCl-Pi and Residual-P) was the highest (46.4%-46.7%), followed by moderately decomposable phosphorus (NaOH-Pi, NaOH-Po and Sonic-Pi) (40.0%-44.0%), and the easily decomposable phosphorus (Resin-Pi, NaHCO3-Pi and NaHCO3-Po) was the lowest (9.5%-13.3%). With increasing invasion years of S. alterniflora, soil phosphorus forms and their spatial distributions were greatly altered. The contents of moderately decomposable phosphorus, hardly decomposable phosphorus, and total phosphorus (TP) generally increased, while easily decomposable phosphorus content generally decreased. Compared with SA1, the contents of moderately decomposable phosphorus, hardly decomposable phosphorus and TP in SA2 increased by 11.5%, 9.7% and 10.5%, while those in SA3 increased by 24.8%, 13.2% and 13.5%, respectively. The distribution of phosphorus forms was greatly altered with increasing invasion years, which was dependent on the variations of key factors such as EC, pH value and grain composition. The implementation of regular mowing activities for S. alterniflora in the Minjiang River estuary in recent years, to some extent, reduced the return of phosphorus from residues to soils and decreased the availability of the easily decomposable phosphorus in soils.


Assuntos
Solo , Áreas Alagadas , China , Estuários , Espécies Introduzidas , Fósforo/análise , Poaceae , Rios , Hidróxido de Sódio , Solo/química
7.
Sci Immunol ; : eabp8328, 2022 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-35549298

RESUMO

Key features of immune memory are greater and faster antigen-specific antibody responses to repeat infection. In the setting of immune-evading viral evolution, it is important to understand how far antibody memory recognition stretches across viral variants when memory cells are recalled to action by repeat invasions. It is also important to understand how immune recall influences longevity of secreted antibody responses. We analyzed SARS-CoV-2 variant recognition, dynamics of memory B cells and secreted antibody over time after infection, vaccination, and boosting. We find that a two-dose SARS-CoV-2 vaccination regimen given after natural infection generated greater longitudinal antibody stability and induced maximal antibody magnitudes with enhanced breadth across Beta, Gamma, Delta and Omicron variants. A homologous 3rd mRNA vaccine dose in COVID-naïve individuals conferred greater cross-variant evenness of neutralization potency with stability that was equal to the hybrid immunity conferred by infection plus vaccination. Within unvaccinated individuals who recovered from COVID, enhanced antibody stability over time was observed within a subgroup of individuals that recovered more quickly from COVID and harbored significantly more memory B cells cross-reactive to endemic coronaviruses early after infection. These cross-reactive clones map to the conserved S2 region of SARS-CoV-2 spike with higher somatic hypermutation levels and greater target affinity. We conclude that SARS-CoV-2 antigen challenge histories in humans influence not only the speed and magnitude of antibody responses, but also functional cross-variant antibody repertoire composition and longevity.

8.
bioRxiv ; 2022 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-35547850

RESUMO

The Omicron subvariant BA.2 has become the dominant circulating strain of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in many countries. We have characterized structural, functional and antigenic properties of the full-length BA.2 spike (S) protein and compared replication of the authentic virus in cell culture and animal model with previously prevalent variants. BA.2 S can fuse membranes more efficiently than Omicron BA.1, mainly due to lack of a BA.1-specific mutation that may retard the receptor engagement, but still less efficiently than other variants. Both BA.1 and BA.2 viruses replicated substantially faster in animal lungs than the early G614 (B.1) strain in the absence of pre-existing immunity, possibly explaining the increased transmissibility despite their functionally compromised spikes. As in BA.1, mutations in the BA.2 S remodel its antigenic surfaces leading to strong resistance to neutralizing antibodies. These results suggest that both immune evasion and replicative advantage may contribute to the heightened transmissibility for the Omicron subvariants.

9.
Front Pharmacol ; 13: 849110, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35571075

RESUMO

Selaginella doederleinii Hieron is a traditional Chinese medicinal herb widely used to treat different cancers. Previously, we showed that the total bioflavonoid extract of S. doederleinii (TBESD) exhibits anti-carcinogenic activities both in vitro and in vivo. However, the plasma protein binding and pharmacokinetics parameters of TBESD remain unclear. To investigate plasma protein binding, tissue distribution, and excretion of TBESD, rats were administered a single dose of TBESD (600 mg/kg) intragastrically and tissue distribution and excretion of TBESD components were determined by rapid high-performance liquid chromatography and tandem mass spectrometry. TBESD binding to human serum albumin (HSA) was assessed by fluorescence spectroscopy. TBESD components amentoflavone, delicaflavone, robustaflavone, 2″,3″-dihydro-3',3‴-biapigenin, and 3',3‴-binaringenin were rapidly absorbed and distributed in various tissues, mostly in the lungs, kidneys, and ovaries, without long-term accumulation. The excretion of bioflavonoids occurred mostly via the intestinal tract and constituted 30% of the administered dose up to 48 h. Spectral analysis indicated that TBESD had a dynamic quenching effect on HSA by binding to one HSA site through hydrophobic interactions and hydrogen bond formation. This is the first comprehensive report on the tissue distribution, excretion, and plasma protein binding of TBESD. This study provides important information on TBESD pharmacokinetics necessary for its further development into a therapeutic form for clinical applications.

10.
IEEE Trans Cybern ; PP2022 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-35560094

RESUMO

This article addresses the finite-time consensus tracking control problem for nonlinear multiagent systems (MASs), in which state variables are unmeasured and nonlinear functions are totally unknown. An observer is designed to estimate state variables and fuzzy-logic systems are employed to approximate nonlinearities. Then, an observer-based adaptive fuzzy consensus tracking controller is developed by using the backstepping technique and constructing a novel barrier Lyapunov function with the consideration of the characteristics of MASs. The proposed control protocol can guarantee that: 1) all signals in the closed-loop system keep bounded and 2) the consensus tracking error converges to a prespecified region of the origin in the prescribed finite time. Compared with the existing observer-based finite/fixed-time control protocols, the settling time and the convergence region in our work can be both preassigned by the designer and not affected by the unknown positive constant, which lies in the Lyapunov derivative inequality. Finally, two comparison simulation examples, including a numerical example and a practical example, check the availability of the designed control scheme.

11.
Ecotoxicol Environ Saf ; 236: 113463, 2022 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-35367890

RESUMO

Synthetic musks (SMs) have been widely used as odor additives in personal care products (PCPs). Dermal exposure to SMs is the main pathway of the accumulation of these chemicals in human kerateins and poses potential health risks. In this study, in silico methods were established to reduce the human health risk of SMs from dermal exposure by investigating the risk mechanisms, designing lower bioaccumulation ability SMs and suggesting proper PCP ingredients using molecular docking, molecular dynamics simulation, and quantitative structure-activity relationship (QSAR) models. The binding energy, a parameter reflecting the binding ability of SMs and human keratin protein (4ZRY), was used as the indicator to assess the human health risk of SMs. According to the mechanism analysis, total energy was found as the most influential molecular structural feature influencing the bioaccumulation ability of a SM, and as one of the main factors influencing the function (i.e., odor sensitivity) of an SM. The 3D-QSAR models were constructed to control the human health risk of SMs by designing lower-risk SMs derivatives. The phantolide (PHAN)- 58 was determined to be the optimum SM derivative with lower bioaccumulation ability (reduced 17.25%) and improved odor sensitivity (increased 7.91%). A further reduction of bioaccumulation ability of PHAN-58 was found when adding proper body wash ingredients (i.e., alkyl ethoxylate sulfate (AES), dimethyloldimethyl (DMDM), EDTA-Na4, ethylene glycol distearate (EGDS), hydroxyethyl cellulose (HEC), lemon yellow and octyl glucose), leading to a significant reduction of the bioaccumulation ability (42.27%) compared with that of PHAN. Results demonstrated that the proposed theoretical mechanism and control strategies could effectively reduce the human health risk of SMs from dermal exposure.


Assuntos
Cosméticos , Humanos , Simulação de Acoplamento Molecular , Odorantes , Relação Quantitativa Estrutura-Atividade , Receptores Proteína Tirosina Quinases , Receptores Colinérgicos , Medição de Risco
12.
Risk Manag Healthc Policy ; 15: 543-552, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35386278

RESUMO

Objective: Falls often occur in patients with diabetic neuropathy due to biomechanical alternation. The implication of diabetic peripheral neuropathy (DPN) on gait and balance remains poorly understood. Methods: A total of 11 dynamic gait, balance and electrophysiological parameters were evaluated in 176 participants. The biomechanical parameters were compared between groups. Results: Stride length and stride velocity were significantly lower in all subgroups of DPN compared with healthy subjects (p<0.05). Stance phase and double support phase were significantly higher, but swing phase were significantly lower across all subgroups of DPN than healthy subjects (p<0.05). Under eyes-open standing, the ML and AP range parameters of CoM sway, ankle sway and hip sway, CoM sway index, ankle swing index in both subclinical and confirmed DPN patients were all significantly higher compared to healthy subjects (p<0.05). Under eyes-closed standing, AP range parameters of CoM sway in subclinical DPN and confirmed DPN patients were significantly higher than healthy subjects (p<0.05). The hip sway areas in diabetics were significantly higher compared to healthy subjects (p<0.05). Conclusion: The abnormal biomechanical parameters existed in the early stages of patients with DPN. The static balance under eyes-open and eye-closed condition is maintained by ankle joint compensation strategy and hip joint protection strategy. An early evaluation and better risk management is essential for diabetic patients with a history of more than 5 years even without DPN clinical symptoms and signs. Clinical Trial Registration Number: No. ChiCTR1800019179, www.chictr.org.cn.

13.
Dig Dis Sci ; 2022 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-35384622

RESUMO

BACKGROUND: Current guidelines suggest antibiotics prophylaxis is not necessary for patients with orthopedic prosthetics undergoing gastrointestinal endoscopy. Clinical evidence to support this recommendation is lacking. AIMS: To analyze the association between inpatient gastrointestinal endoscopy and prosthetic joint infection (PJI) in patients with a recent arthroplasty. METHODS: We included patients admitted from July to October of each calendar year (index admissions) who had an arthroplasty in the same calendar year prior to the index admission. We followed the occurrence of PJI for 60 days after the index admission. Only admissions from July to October were chosen as index admissions, and the follow-up period was limited to 60 days because the database structure prohibits the analysis of events in different calendar years. We compared the rate of 60-day PJI between those who had gastrointestinal endoscopy on index admissions to those who had not. We excluded patients aged less than 18 years, who died on index admission, or had any infection in the same calendar year before or during the index admission. RESULTS: Of 1,831,218 patients with arthroplasty, 88,345 met the inclusion criteria, out of which 5,855 had gastrointestinal endoscopy. The rate of 60-day PJI in those who had endoscopy was 0.23%, and in those who had not was 0.52% (P < 0.001). EGD without excision (adjusted odds ratio [95% confidence interval]: 0.20 [0.03-1.42], P = 0.107), EGD with excision (0.58 [0.21-1.60], P = 0.295), colonoscopy without excision (0.43 [0.11-1.72], P = 0.233), colonoscopy with excision (0.31 [0.04-2.21], P = 0.241), and PEG/PEJ (0.38 [0.05-2.71], P = 0.337) were not associated with risk of 60-day PJI. We found no PJI cases in patients underwent esophageal dilation, ERCP, and EUS with FNA. CONCLUSIONS: Gastrointestinal endoscopy in hospitalized patients with a recent previous arthroplasty is not associated with an increased risk of 60-day prosthetic joint infection.

14.
Am J Obstet Gynecol ; 2022 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-35430229

RESUMO

BACKGROUND: SARS-CoV-2 infection is associated with enhanced disease severity in pregnant women. Despite the potential of COVID-19 vaccines to reduce severe disease, vaccine uptake remained relatively low among pregnant women. Just as coordinated messaging from the CDC and leading obstetrics organizations began to increase vaccine confidence in this vulnerable group, the evolution of SARS-CoV-2 variants of concerns (VOC) including the Omicron VOC raised new concerns about vaccine efficacy, given their ability to escape vaccine-induced neutralizing antibodies. Early data point to a milder disease course following omicron VOC infection in vaccinated individuals. Thus, these data suggest that alternate vaccine induced immunity, beyond neutralization, may continue to attenuate omicron disease, such as antibody-Fc-mediated activity. OBJECTIVES: To test whether vaccine induced antibodies raised in pregnancy continue to bind and leverage Fc-receptors against VOCs including the Omicron variant. STUDY DESIGN: VOC including Omicron receptor binding domain (RBD) or full Spike specific antibody isotype binding titers and FcγR binding were analyzed in pregnant women after the full dose regimen of either Pfizer/BioNTech BNT62b2 (n=10) or Moderna mRNA-1273 (n=10) vaccination using a multiplexing Luminex assay. RESULTS: Reduced, isotype recognition was observed to the Omicron receptor binding domain (RBD) following both vaccines, with relatively preserved, albeit reduced, recognition of Omicron full Spike by IgM and IgG antibodies. Despite the near complete loss of Fc-receptor binding to the Omicron RBD, Fc-receptor binding was more variable but largely preserved to the Omicron Spike. CONCLUSION: Reduced binding titers to the Omicron RBD aligns with observed loss of neutralizing activity. Despite the loss of neutralization, preserved, albeit reduced, Omicron Spike recognition and Fc-receptor binding potentially continues to attenuate disease severity in pregnant women.

15.
Proc Natl Acad Sci U S A ; 119(15): e2120787119, 2022 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-35385357

RESUMO

SignificanceWe provide transcriptomic insights into differences between pediatric and adult T cell acute lymphoblastic leukemia (T-ALL) patients through an international collaborative effort integrating RNA-sequencing data of 707 patients. Ten subtypes were identified, each characterized by distinct gene mutation profiles and dysregulated expression signatures of leukemogenic factors, and associated with T cell development stages. Adult T-ALL tends to have characteristics of early T cell precursor ALL, mostly corresponding to the mixed phenotype acute leukemia, whereas pediatric T-ALL shows a wide spectrum of aberrant molecular features, from early T cell precursor to mature T cell compartments. Our findings have important implications for disease mechanism of T-ALL that differs between pediatric and adult patients, facilitating further refined targeted therapy.


Assuntos
Leucemia-Linfoma Linfoblástico de Células T Precursoras , Transcriptoma , Criança , Humanos , Mutação , Leucemia-Linfoma Linfoblástico de Células T Precursoras/genética
16.
Nat Methods ; 19(4): 381-383, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35396469
17.
Materials (Basel) ; 15(7)2022 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-35407685

RESUMO

In this study, a negative replica layer of leaf surface microstructures was used to cover the top surfaces of semitransparent thin-film luminescent solar concentrators (LSCs) to enhance the concentrators' performance. With low reflection on the air-glass interface of the glass plate in a thin-film LSC, a negative replica layer enables the scattering of incident sunlight and increases the path of light transmitted into the LSC and the thin phosphor layer at the bottom surface of the LSC. The incident sunlight is therefore more likely to interact with the phosphor particles in the thin-film phosphor layer, thereby enhancing the performance of the LSC. In this study, semitransparent thin-film LSCs with different inorganic phosphors were examined. The experimental results revealed that the optical collection efficiency of semitransparent thin-film LSCs covered with negative replica layers of leaf surface microstructures was higher than that of the semitransparent thin-film LSCs without negative replica layers. Furthermore, the LSCs with negative replica layers with high haze ratios exhibited high optical collection efficiency. Integrating negative replica layers of leaf surface microstructures as semitransparent layers in thin-film LSCs may optimize the application of LSCs in building-integrated photovoltaics (BIPVs).

18.
Artigo em Inglês | MEDLINE | ID: mdl-35384041

RESUMO

BACKGROUND AND AIM: Humans with inborn errors of immunity (IEI), or primary immunodeficiencies, may be associated with a potential risk factor for early-onset gastrointestinal (GI) cancer. METHODS: We systematically reviewed all cases with clinical diagnoses of both an IEI and a GI cancer in three databases (MEDLINE, SCOPUS, and EMBASE). In total, 76 publications satisfying our inclusion criteria were identified, and data for 149 cases were analyzed. We also searched our institutional cancer registry for such cases. RESULTS: We identified 149 patients with both an IEI and a GI cancer, 95 presented gastric cancer, 13 small bowel cancer, 35 colorectal cancer, and 6 had an unspecified cancer or cancer at another site. Gastric and colon adenocarcinomas were the most common. For both gastric and colorectal cancers, age at onset was significantly earlier in patients with IEIs than in the general population, based on the SEER database. Common variable immunodeficiency (CVID) was the most common IEI associated with gastrointestinal cancer. About 12% of patients had molecular genetic diagnoses, the three most frequently implicated genes being ATM, CARMIL2, and CTLA4. Impaired humoral immunity and Epstein-Barr virus (EBV) infection were frequently reported as factors potentially underlying early-onset GI cancers in patients with IEIs. We identified one patient with CVID and early-onset gastric adenocarcinoma, recurrent diarrhea, and gastrointestinal CMV infection from a retrospective survey. CONCLUSION: Patients with IEIs should be considered at risk of early-onset GI cancers and should therefore undergo cancer screening at an earlier age.

19.
Cell Rep ; 39(4): 110729, 2022 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-35452593

RESUMO

The Omicron variant of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), bearing an unusually high number of mutations, has become a dominant strain in many countries within several weeks. We report here structural, functional, and antigenic properties of its full-length spike (S) protein with a native sequence in comparison with those of previously prevalent variants. Omicron S requires a substantially higher level of host receptor ACE2 for efficient membrane fusion than other variants, possibly explaining its unexpected cellular tropism. Mutations not only remodel the antigenic structure of the N-terminal domain of the S protein but also alter the surface of the receptor-binding domain in a way not seen in other variants, consistent with its remarkable resistance to neutralizing antibodies. These results suggest that Omicron S has acquired an extraordinary ability to evade host immunity by excessive mutations, which also compromise its fusogenic capability.


Assuntos
COVID-19 , SARS-CoV-2 , COVID-19/genética , Humanos , Mutação/genética , SARS-CoV-2/genética , Glicoproteína da Espícula de Coronavírus
20.
Nature ; 604(7905): 273-279, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35418634

RESUMO

Metals with nanocrystalline grains have ultrahigh strengths approaching two gigapascals. However, such extreme grain-boundary strengthening results in the loss of almost all tensile ductility, even when the metal has a face-centred-cubic structure-the most ductile of all crystal structures1-3. Here we demonstrate that nanocrystalline nickel-cobalt solid solutions, although still a face-centred-cubic single phase, show tensile strengths of about 2.3 gigapascals with a respectable ductility of about 16 per cent elongation to failure. This unusual combination of tensile strength and ductility is achieved by compositional undulation in a highly concentrated solid solution. The undulation renders the stacking fault energy and the lattice strains spatially varying over length scales in the range of one to ten nanometres, such that the motion of dislocations is thus significantly affected. The motion of dislocations becomes sluggish, promoting their interaction, interlocking and accumulation, despite the severely limited space inside the nanocrystalline grains. As a result, the flow stress is increased, and the dislocation storage is promoted at the same time, which increases the strain hardening and hence the ductility. Meanwhile, the segment detrapping along the dislocation line entails a small activation volume and hence an increased strain-rate sensitivity, which also stabilizes the tensile flow. As such, an undulating landscape resisting dislocation propagation provides a strengthening mechanism that preserves tensile ductility at high flow stresses.


Assuntos
Cobalto , Metais , Cobalto/química , Teste de Materiais , Metais/química , Resistência à Tração
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