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Background: Chronic obstructive pulmonary disease (COPD) is a common respiratory disease with acute exacerbation (AECOPD) being a common sequalae which negatively impact health status, rates of hospitalization and readmission, and disease progression. N‐acetylcysteine (NAC) has been studied in COPD in both stable state and acute exacerbations, which has been shown to have small beneficial effects in stable COPD, as well as AECOPD. Yet, there has been lack of study with well‐designed protocol to assess the role of NAC in more objective outcomes in AECOPD. Methods: This is a double‐blind randomized controlled trial. Patients will be randomized in 1:1 ratio to receive oral NAC at 600 mg twice daily or placebo twice daily with standard of care. Partial pressure of oxygen (PaO2), partial pressure of carbon dioxide (PaCO2) and the ratio of partial pressure arterial oxygen and fraction of inspired oxygen (PaO2/FiO2) will be measured on days 1 and 7. The following will be measure at baseline and on day 4 and 7: Forced expiratory volume in one second (FEV1), 24‐hour sputum volume, oxygen saturation (SaO2), end‐tidal CO2, Leicester Cough Questionnaire (LCQ) score, COPD Assessment Test (CAT) score, grading of wheeze and grade of dyspnoea; blood inflammatory markers (leucocyte count, neutrophil count, erythrocyte sedimentation rate (ESR), C‐reactive protein (CRP) and high sensitivity CRP (hs‐CRP)). Patients will be randomized to oral NAC at 600 mg twice daily or placebo for 7 days. The main outcome measures include: The difference in PaO2 on day 7. Secondary outcome: Change in following parameters on day 4/7 from baseline: FEV1, sputum volume, CAT score, LCQ score, SaO2, grade of wheeze; mMRC Dyspnoea Scale, end‐tidal CO2, blood inflammatory marker, change in PaO2/FiO2 ratio from baseline to day 7, PaCO2 on day 7, 28 and 90 days' mortality, time to wean off supplemental oxygen, length of stay. Primary and secondary outcomes will be compared among the two treatment groups with two‐sample t‐test. Discussion: We hypothesize that NAC use in COPD exacerbation can provide benefits in clinical and laboratory parameters. Trial Registration: Name of the registry: ClinicalTrials.gov Trial registration number: NCT05706402. URL of the trial registry record for this trial: https://classic.clinicaltrials.gov/ct2/show/NCT05706402 Date of registration: Registered on 11th January 2023 Funding of the trial: The Health and Medical Research Fund (HMRF). Name and contact information for the trial sponsor: Wang Chung Kwok, Clinical Assistant Professor, Honorary Associate Consultant, Queen Mary Hospital, The University of Hong Kong, Hong Kong. Role of sponsor: The funder is not involved in the planning of the study, gathering, analysing, and interpreting the data, or in preparing the manuscript. [ABSTRACT FROM AUTHOR]

The conversion of diverse non-petroleum carbon elements, such as coal, biomass, natural/shale gas, and even CO2, into cleaner hydrocarbon fuels and useful chemicals relies heavily on syngas, which is a combination of CO and H2. Syngas conversions, which have been around for almost a century, will probably become even more important in the production of energy and chemicals due to the rising need for liquid fuels and chemical components derived from sources of carbon other than crude oil. Although a number of syngas-based technologies, including the production of methanol, Fischer–Tropsch (FT) synthesis, and carbonylation, have been industrialized, there is still a great need for new catalysts with enhanced activity and adjustable product selectivity. New novel materials or different combinations of materials have been investigated to utilize the synergistic effect of these materials in an effective way. Magnetic materials are among the materials with magnetic properties, which provide them with extra physical characteristics compared to other carbon-based or conventional materials. Moreover, the separation of magnetic materials after the completion of a specific application could be easily performed with a magnetic separation process. In this review, we discuss the synthesis processes of various magnetic nanomaterials and their composites, which could be utilized as catalysts for syngas production and conversion. It is reported that applying an external magnetic field could influence the outcomes of any applications of magnetic nanomaterials. Here, the possible influence of the magnetic characteristics of magnetic nanomaterials with an external magnetic field is also discussed. [ABSTRACT FROM AUTHOR]

Since the U.S. Embassy in Beijing placed an air quality sensor on its roof and began publishing the results on Twitter in 2008, air quality has gained widespread attention on Chinese microblogs. When the Chinese government introduced new air quality standards in 2012, some hailed this as a victory for Chinese microbloggers, signifying the emergence of social media as a democratizing force leading to greater citizen power. Using a representative sample of microblog posts collected from October 2012 to June 2013 on the topic of air pollution, as well as contextual information from a variety of sources, we examine how the government, companies, nongovernmental organizations, and individuals approach the Chinese social media landscape. We find that although microblogs are capable of empowering citizens to advance an environmental cause, social media have also been increasingly employed by the government as a tool for social monitoring and control and by companies as a platform for profiting from air pollution. [ABSTRACT FROM AUTHOR]

Background: While there are postulations that asthma is potentially associated with severe coronavirus disease 2019 (COVID-19), there has been conflicting results from studies on the impact mild-to-moderate COVID-19 on asthma control after recovery. Methods: A case control study on the association between mild-to-moderate COVID-19 and asthma control post infection was conducted. The primary outcome was a reduction in Asthma Control Test (ACT) score by ≥ 3 points post-COVID infection. The secondary outcomes included the change in ACT score, the proportion of patient with ACT score who dropped to ≤ 15 on enrolment visit and the need for escalation of asthma maintenance therapy. Results: Out of the total of 221 adult patients with asthma recruited, 111 had mild-to-moderate COVID-19 within 30 to 270 days prior to study enrolment. The adjusted odds ratio (aOR) for a reduction in ACT score by ≥ 3 points after COVID-19 was 3.105 (95% CI = 1.385–6.959, p = 0.006). The odds of escalation of asthma maintenance therapy by at least 1 Global Initiative for Asthma (GINA) step was 4.733 (95% CI = 1.151–19.467, p = 0.031) and asthma patient are more likely to become uncontrolled after COVID-19 [aOR = 5.509 (95% CI = 1.061–28.600, p = 0.042)]. Conclusion: Mild-to-moderate COVID-19 among asthma patients, upon recovery, was associated with worsening of asthma symptom, lower ACT score, a higher need for escalation of asthma maintenance therapy and more uncontrolled asthma. [ABSTRACT FROM AUTHOR]

Pluripotent stem cells are derived from the inner cell mass of preimplantation embryos, and display the ability of the embryonic founder cells by forming all three germ lineages in vitro. It is well established that the cellular niche plays an important role in stem cell maintenance and differentiation. Stem cells generally have limited function without the specialized microenvironment of the niche that provides key cell–cell contact, soluble mediators, and extracellular matrices. We were interested in the role that Wnt signaling, in particular Wnt3a, played in human embryonic stem cell (hESC) differentiation to hepatic endoderm in vitro. hESC differentiation to hepatic endoderm was efficient in pure stem cell populations. However, in younger hESC lines, generating stromal cell mesenchyme, our model was very inefficient. The negative effect of stroma could be reversed by pretreating hESCs with Wnt3a prior to the onset of hepatocyte differentiation. Wnt3a pretreatment reinstated efficient hESC differentiation to hepatic endoderm. These studies represent an important step in understanding hepatocyte differentiation from hESCs and the role played by the cellular niche in vitro. [ABSTRACT FROM AUTHOR]

Hematopoietic differentiation of embryonic stem (ES) cells can be enhanced by co-culture with stromal cells derived from hematopoietic tissues and by overexpression of the transcription factor HOXB4. In this study, we compare the hematopoietic inductive effects of stromal cell lines derived from different subregions of the embryonic aorta-gonad-mesonephros tissue with the commonly used OP9 stromal cell line and with HOXB4 activation. We show that stromal cell lines derived from the aorta and surrounding mesenchyme (AM) act at an earlier stage of the differentiation process compared with the commonly used OP9 stromal cells. AM stromal cells were able to promote the further differentiation of isolated brachyury-GFP+mesodermal cells into hematopoietic progenitors, whereas the OP9 stromal cells could not support the differentiation of these cells. Co-culture and analyses of individual embryoid bodies support the hypothesis that the AM stromal cell lines could enhance the de novo production of hematopoietic progenitors, lending support to the idea that AM stromal cells might act on prehematopoietic mesoderm. The induction level observed for AM stromal cells was comparable to HOXB4 activation, but no additive effect was observed when these 2 inductive strategies were combined. Addition of a γ-secretase inhibitor reduced the inductive effects of both the stromal cell line and HOXB4, providing clues to possible shared molecular mechanisms. [ABSTRACT FROM AUTHOR]