An aggregated understanding of the influence of aqueous ammonia pretreatment on the physical deconstruction of cell walls in sugar beet pulp.

The underlying interplay between physicochemical property and enzymatic hydrolysis of cellulose still remains unclear. The impacts of matrix glycan composition of sugar beet pulp (SBP) on physical structure and saccharification efficiency were emphasized. The results showed that aqueous ammonia (AA) pretreatment could remove the non-cellulosic polysaccharides and destroy the linkage between the pectin and lignin. The cellulose supramolecule was changed significantly after AA pretreatment, in terms of the decline in hardness, gumminess, springiness, thickness and degree of polymerization. Furthermore, vascular cell was exposed and degraded. The highest reducing sugar yield of 355.06 mg/g was obtained from the pretreated SBP (80 °C) with enzyme loading of 30 U/g, which was 1.01 times higher than that of the untreated SBP. This research also supported the idea that recognizing and precisely removing the primary epitopes in cell walls might be an ideal strategy to accomplish the improved enzymatic hydrolysis through mild pretreatment.

Sequence Variation of Candida albicans Sap2 Enhances Fungal Pathogenicity via Complement Evasion and Macrophage M2-Like Phenotype Induction.

Candida albicans (C. albicans) is an opportunistic pathogen increasingly causing candidiasis worldwide. This study aims to investigate the pattern of systemic immune responses triggered by C. albicans with disease associated variation of Sap2, identifying the novel evasion strategies utilized by clinical isolates. Specifically, a variation in clinical isolates is identified at nucleotide position 817 (G to T). This homozygous variation causes the 273rd amino acid exchange from valine to leucine, close to the proteolytic activation center of Sap2. The mutant (Sap2-273L) generated from SC5314 (Sap2-273V) background carrying the V273L variation within Sap2 displays higher pathogenicity. In comparison to mice infected with Sap2-273V strain, mice infected with Sap2-273L exhibit less complement activation indicated by less serum C3a generation and weaker C3b deposition in the kidney. This inhibitory effect is mainly achieved by Sap2273L -mediated stronger degradation of C3 and C3b. Furthermore, mice infected with Sap2-273L strain exhibit more macrophage phenotype switching from M0 to M2-like and more TGF-ß release which further influences T cell responses, generating an immunosuppressed cellular microenvironment characterized by more Tregs and exhausted T cell formation. In summary, the disease-associated sequence variation of Sap2 enhances pathogenicity by complement evasion and M2-like phenotype switching, promoting a more efficient immunosuppressed microenvironment.

Quercetin serves as the major component of Xiang-lian Pill to ameliorate ulcerative colitis via tipping the balance of STAT1/PPARγ and dictating the alternative activation of macrophage.

ETHNOPHARMACOLOGICAL RELEVANCE: The traditional Chinese herbal formula, Xiang-lian Pill (XLP), is commonly prescribed for ulcerative colitis (UC) patients to relieve their clinical symptom. Nonetheless, the underlying cellular and molecular mechanisms of XLP's anti-UC effect remain incompletely understood. AIM OF THE STUDY: To evaluate the therapeutic effect and elucidate the possible working mechanisms of XLP in UC treatment. The major active component of XLP was also characterized. MATERIALS AND METHODS: Colitis was induced in C57BL/6 mice with 3% dextran sulfate sodium (DSS) dissolved in drinking water for 7 consecutive days. The UC mice were grouped and treated with XLP (3640 mg/kg) or vehicle orally during the procedure of DSS induction. Mouse body weight, disease activity index (DAI) score and colon length were recorded. Histopathological changes and inflammatory cell infiltration were evaluated by pathological staining and flow cytometric analysis (FACS). Network pharmacology, bioinformatic analysis, widely targeted and targeted metabolomics analysis were performed to screen the potential effective ingredients and key targets. Bone marrow derived macrophages (BMDMs), peripheral blood mononuclear cells (PBMCs), RAW264.7 and THP-1 cells were used to dissect the anti-inflammatory effect of XLP. RESULTS: Oral administration of XLP ameliorated DSS induced mouse colitis, as evidenced by reduced DAI and colonic inflammatory destruction. FACS results demonstrated that XLP treatment effectively restored immune tolerance in colon, inhibited the generation of monocyte derived macrophages and skewed macrophage polarization into M2 phenotype. Network pharmacology analysis suggested that innate effector modules related to macrophage activation comprise the major targets of XLP, and the counter-regulatory STAT1/PPARγ signaling possibly serves as the critical downstream pathway. Subsequent experiments unveiled an imbalance of STAT1/PPARγ signaling in monocytes derived from UC patients, and validated that XLP suppressed LPS/IFN-γ induced macrophage activation (STAT1 mediated) but facilitated IL-4 induced macrophage M2 polarization (PPARγ dependent). Meanwhile, our data showed that quercetin served as the major component of XLP to recapitulate the regulatory effect on macrophages. CONCLUSION: Our findings revealed that quercetin serves as the major component of XLP that regulates macrophage alternative activation via tipping the balance of STAT1/PPARγ, which provides a mechanistic explanation for the therapeutic effect of XLP in UC treatment.

Berberine plays a cardioprotective role by inhibiting macrophage Wnt5a/ß-catenin pathway in the myocardium of mice after myocardial infarction.

Myocardial infarction (MI) is one of the diseases with high fatality rate. Berberine (BBR) is a monomer compound with various biological functions. And some studies have confirmed that BBR plays an important role in alleviating cardiomyocyte injury after MI. However, the specific mechanism is unclear. In this study, we induced a model of MI by ligation of the left anterior descending coronary artery and we surprisingly found that BBR significantly improved ventricular remodeling, with a minor inflammatory and oxidative stress injury, and stronger angiogenesis. Moreover, BBR inhibited the secretion of Wnt5a/ß-catenin pathway in macrophages after MI, thus promoting the differentiation of macrophages into M2 type. In summary, BBR effectively improved cardiac function of mice after MI, and the potential protective mechanism was associated with the regulation of inflammatory responses and the inhibition of macrophage Wnt5a/ß-catenin pathway in the infarcted heart tissues. Importantly, these findings supported BBR as an effective cardioprotective drug after MI.

Polycyclic aromatic hydrocarbons (PAHs) in the Bohai Sea: A review of their distribution, sources, and risks.

The distribution, risks, and sources of polycyclic aromatic hydrocarbons (PAHs) observed in seawater and sediments in the Bohai Sea were reviewed. The ecological risk of total PAHs in seawater was low, but the ecological risks of several individual PAHs (Pyr, BbF, and IcdP) were high. Detected PAHs in sediments rarely had adverse biological effects. High PAH concentrations were identified in Bohai Bay, in the sea area near Qinhuangdao, in Jinzhou Bay, and in Bohai Strait. Low PAH concentrations were found in the central Bohai, in Laizhou Bay, and in the sea area with more intensive ocean currents near Caofeidian. PAH concentrations in the Bohai Sea present a seaward-decreasing trend. Their spatial distribution could be attributed to the influence of human activities (population, industrial activities, and shipping activities), which determined PAH emissions. The PAHs were characterized by local sources, indicating that coal consumption and vehicle emissions were important sources of PAHs. Integr Environ Assess Manag 2022;18:1705-1721. © 2022 SETAC.

Elevated Exhaustion Levels of NK and CD8+ T Cells as Indicators for Progression and Prognosis of COVID-19 Disease.

Background: Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) induced Coronavirus Disease 2019 (COVID-19) has posed a global threat to public health. The immune system is crucial in defending and eliminating the virus and infected cells. However, immune dysregulation may result in the rapid progression of COVID-19. Here, we evaluated the subsets, phenotypic and functional characteristics of natural killer (NK) and T cells in patients with COVID-19 and their associations with disease severity. Methods: Demographic and clinical data of COVID-19 patients enrolled in Wuhan Union Hospital from February 25 to February 27, 2020, were collected and analyzed. The phenotypic and functional characteristics of NK cells and T cells subsets in circulating blood and serum levels of cytokines were analyzed via flow cytometry. Then the LASSO logistic regression model was employed to predict risk factors for the severity of COVID-19. Results: The counts and percentages of NK cells, CD4+ T cells, CD8+ T cells and NKT cells were significantly reduced in patients with severe symptoms. The cytotoxic CD3-CD56dimCD16+ cell population significantly decreased, while the CD3-CD56dimCD16- part significantly increased in severe COVID-19 patients. More importantly, elevated expression of regulatory molecules, such as CD244 and programmed death-1 (PD-1), on NK cells and T cells, as well as decreased serum cytotoxic effector molecules including perforin and granzyme A, were detected in patients with COVID-19. The serum IL-6, IL-10, and TNF-α were significantly increased in severe patients. Moreover, the CD3-CD56dimCD16- cells were screened out as an influential factor in severe cases by LASSO logistic regression. Conclusions: The functional exhaustion and other subset alteration of NK and T cells may contribute to the progression and improve the prognosis of COVID-19. Surveillance of lymphocyte subsets may in the future enable early screening for signs of critical illness and understanding the pathogenesis of this disease.

Long-term infection of SARS-CoV-2 changed the body's immune status.

The outbreak of SARS-CoV-2-associated pneumonia, a disease called COVID-19, has caused a pandemic worldwide. To investigate the immune responses after infection of SARS-CoV-2 in non-critical patients may help to better understand the disease progression. We collected 334 confirmed COVID-19 cases including 212 still in hospital with nucleic acid test positive on halfway for SARS-CoV-2 and 122 discharged from hospital, compared specific antibodies, immune cells, and cytokine changes between the hospitalized and discharged patients. The hospitalized patients had a longer illness time compared with discharged patients. Analysis of viral loads explained long-term or persistent infection of SARS-CoV-2, which existed with the median time of 18.5 days of the positive nucleic acid test. Serum analysis showed that the specific anti-N IgG antibody was positive in all detected patients after infection of two weeks. Neutrophils, Monocytes, NK cells, and CD4+ T cells significantly increased, while total lymphocytes and CD8+ T cells decreased from non-critical hospitalized patients after longer-term infection. Further analysis of the cytokines showed that IL-6, TNF-α, IFN-γ, IL-2, IL-4, and IL-10 from the hospitalized patients were significantly higher, indicating a potential of the increased CD4+ T cell differentiation.

Diabetes is a risk factor for the progression and prognosis of COVID-19.

BACKGOUND: To figure out whether diabetes is a risk factor influencing the progression and prognosis of 2019 novel coronavirus disease (COVID-19). METHODS: A total of 174 consecutive patients confirmed with COVID-19 were studied. Demographic data, medical history, symptoms and signs, laboratory findings, chest computed tomography (CT) as well the treatment measures were collected and analysed. RESULTS: We found that COVID-19 patients without other comorbidities but with diabetes (n = 24) were at higher risk of severe pneumonia, release of tissue injury-related enzymes, excessive uncontrolled inflammation responses and hypercoagulable state associated with dysregulation of glucose metabolism. Furthermore, serum levels of inflammation-related biomarkers such as IL-6, C-reactive protein, serum ferritin and coagulation index, D-dimer, were significantly higher (P < .01) in diabetic patients compared with those without, suggesting that patients with diabetes are more susceptible to an inflammatory storm eventually leading to rapid deterioration of COVID-19. CONCLUSIONS: Our data support the notion that diabetes should be considered as a risk factor for a rapid progression and bad prognosis of COVID-19. More intensive attention should be paid to patients with diabetes, in case of rapid deterioration.