Gas stunning with CO_2 affected meat color,lipid peroxidation, oxidative stress, and gene expression of mitogen-activated protein kinases, glutathione S-transferases,and Cu/Zn-superoxide dismutase in the skeletal muscles of broilers

Background: Meat color and lipid peroxidation are important traits related to meat quality. CO_2 concentration is a critical factor that can affect meat quality in the commercial use of gas stunning(GS). However, the effect and mechanism of CO_2 stunning on meat color and lipid peroxidation during long-term storage remain poorly studied. We aimed to study the effects of GS methods, especial y CO_2 concentration, on meat color and meat lipid peroxidation in broilers during long-term storage at 4 °C and to explore the potential mechanism of meat color change via lipid peroxidation and the inner lipid peroxide scavenging system.Methods: Eighteen broilers were sacrificed after exposure to one of the following gas mixtures for 90 s: 40% CO_2+21% O_2+ 39% N2(G40%), 79% CO_2+ 21% O_2(G79%), or no stunning(0% CO_2, control). Meat color, serum variables,enzyme activities, and the gene expression of mitogen-activated protein kinase(MAPK), nuclear factor-erythroid2-related factor 2(Nrf2), glutathione S-transferase(GST) and superoxide dismutase(SOD) were determined.(Continued on next page)Results: The concentrations of serum triiodothyronine(T3, P = 0.03) and the ratio of serum free triiodothyronine/free thyroxine(FT3/FT4, P < 0.01) were decreased, whereas levels of serum cortisol(P < 0.01) were increased in the 40%CO_2 group compared with the control group. Additionally, the thiobarbituric acid-reactive substances(TBARS)3 d(P < 0.01) and TBARS6 d(P = 0.01) in breast meat and the TBARS3 din thigh meat(P < 0.01) were increased in the40% CO_2 group compared with the control group. Serum T3 was negatively correlated with TBARS6 dboth in the breast and thigh meat(r =-0.63, P < 0.01 and r =-0.47, P = 0.05 respectively). T3/T4 was negatively correlated with TBARS6 din the breast meat and in the thigh meat(r =-0.57, P = 0.01; and r =-0.53, P = 0.03 respectively). Compared with the control group, Lightness(L*)1 d(P = 0.03) and L*9 d(P < 0.01) were increased, whereas total chromatic aberration(E*)1 d(P = 0.05) and E*3 d(P < 0.01) were decreased in the breast meat of both the G40% and G79% groups. The values of yel owness(b*)3 d(P = 0.01), b*6 d(P < 0.01) and E*6 d(P < 0.01) in the thigh meat were lower in both the G40% and G79% groups than in the control group. In the breast muscle, the m RNA levels of c-Jun N-terminal kinase 2(JNK2, P = 0.03),GSTT1(P = 0.04), and SOD1(P = 0.05) were decreased, and the m RNA levels of JNK1(P = 0.07), Nrf2(P = 0.09), and GSTA3(P = 0.06) were slightly lower in both the G40% and G79% groups compared with the control group. However, among these genes, only the m RNA level of JNK1 was decreased in the G40% group compared with the control group and the G79% group(P = 0.03) in the thigh muscle.Conclusions: Compared with the control group, meat color quality in the breast meat was decreased, and the expression of genes in the MAPK/Nrf2/ARE(antioxidant responsive element) antioxidant pathway in breast muscle was partly suppressed by GS of both 40% and 79% CO_2. However, oxidative stress and meat lipid peroxidation during storage were aggravated by GS with 40% CO_2 compared to GS with 79% CO_2 and no GS.

Effects of phytase supplementation on growth performance, slaughter performance, growth of internal organs and small intestine, and serum biochemical parameters of broilers

The objective of this study was to investigate the effects of phytase supplementation on growth performance, slaughter performance, growth of internal organs and small intestine, and serum biochemical indices of broilers. A total of 360 1-day-old Ross 308 broilers were randomly divided into 4 groups with 3 replicates and 30 broilers per replicate (15 male, 15 female). The treatments were fed with basal diet supplemented with 0%, 0.01%, 0.02% and 0.03% phytase. The results showed that: 1) Phytase supplementation increased the body weight gain and the body weight of Ross 308 broilers (P serum calcium (Ca) consistency was 0.02%. According to the above analysis, the feasible supplementation of phytase (enzyme activity for 5000 u/g) in broiler dietary was 0.02%.

Pathogens of first-episode pulmonary infection in 141 children with chronic granulomatous disease

To the Editor:Chronic granulomatous disease(CGD)is an inherited primary immunodeficiency disease characterized by recurrent life-threatening bacterial or fungal infection and tissue granuloma formation.^([1])Pulmonary infection is the most frequent manifestation,affecting nearly 80%of patients,[2]and remains the major cause of morbidity and mortality in patients with CGD.Details of the pathogenic microorganisms responsible for first-episode pulmonary infection provide information on the spectrum of infection in patients with CGD,help guide the empirical choice of antibiotics or antifungal therapy,and contribute to the early identification and management of CGD.Aspergillus is the commonest causative agent of pulmonary infection,but the distribution of other pathogens varies among countries.^([2–5])Few studies have investigated the etiology of pulmonary infection in CGD in a large cohort in China.

Advances in metal-organic frameworks for efficient separation and purification of natural gas

Natural gas is an essential chemical raw material and a promising clean energy source,which is widely used and increasingly in demand.Gas separation processes significantly impact the current needs of human society.The traditional low temperature liquefaction distillation method of natural gas has high cost of gas separation and purification,which limits its wide application.As a new kind of porous materials,metal-organic frameworks(MOFs)have shown excellent gas separation and purification prospects due to their ultra-high specific surface area,easily modified pore surface,structural design,and functionalization.Here,we summarize the recent research progress of using MOFs adsorbent for the separation of natural gas,including C_(3)H_(8)/CH_(4),C_(2)H_(6)/CH_(4),H_(2)S/CH_(4),CO_(2)/CH_(4),and CH_(4)/N_(2).Furthermore,bottlenecks and possible research directions for further exploration are discussed.

Hierarchical pomegranate-structure design enables stress management for volume release of Si anode

Si is a promising anode material for lithium-ion batteries owing to its high theoretical capacity.How-ever,large stress during(de)lithiation induces severe structural pulverization,electrical contact failure,and unstable solid-electrolyte interface,which hampers the practical application of Si anode.Herein,a Si-based anode with a hierarchical pomegranate-structure(HPS-Si)was designed to modulate the stress variation,and a sub-micronized Si-based sphere was assembled by the nano-sized Si nanospheres with sub-nanometer-sized multi-phase modification of the covalently linked SiO_(2-x),SiC,and carbon.The sub-micronized HPS-Si stacked with Si nanospheres can avoid agglomerates during cycling due to the high surface energy of nanomaterials.Meanwhile,the reasonable pore structure from SiO_(2) reduction owing to density difference is enough to accommodate the limited volume expansion.The Si spheres with a size of about 50 nm can prevent self-cracking.SiO_(2-x),and SiC as flexible and rigid layers,have been syner-gistically used to reduce the surface stress of conductive carbon layers to avoid cracking.The covalent bonding immensely strengthens the link of the modification with Si nanospheres,thus resisting stress effects.Consequently,a full cell comprising an HPS-Si anode and a LiCoO_(2) cathode achieved an energy density of 415 Wh kg^(-1) with a capacity retention ratio of 87.9%after 300 cycles based on the active ma-terials.It is anticipated that the hierarchical pomegranate-structure design can provide inspiring insights for further studies of the practical application of silicon anode.

Mineralization of aqueous pentachlorophenolate by anodic contact glow discharge electrolysis

Exhaustive mineralization of pentachlorophenolate ion（PCP） in phosphate buffer was carried out using anodic contact glow discharge electrolysis（CGDE）,in which plasma was sustained between the electrolyte and anode.During CGDE,PCP degraded smoothly.The amount of total organic carbon decreased significantly,indicating the eventual conversion of the carbon atoms of benzene nucleus to inorganic carbons.Furthermore,chlorine atoms in PCP were liberated as chloride ions.As a primary intermediate product,2,3,5,6tetrachloro-1,4-benzoquinone was detected,and oxalate and formate as byproducts were also found.It was revealed that disappearance of PCP obeyed first-order kinetics.The reaction rate was generally unaffected by both O2 and inert gases in the cell,although it decreased by raising initial pH of solution.In addition,a plausible reaction pathway involving hydroxyl radical was proposed.

Synthesis of an ordered porous carbon with the dual nitrogen-doped interfaces and its ORR catalysis performance

Both nitrogen-doping feature and pore structure are critical factors for developing nitrogen-doped carbons based catalysts with a high performance toward oxygen reduction reaction(ORR).Herein,a simple one-step CVD of acetylene and acetonitrile vapor method using silanized SBA-15 as a template has been developed to synthesize an ordered porous carbon(OPC) with dual nitrogen-doped interfaces.The optimized sample as prepared with the CVD of 4 h at 750℃ contains two types of ordered mesopores that one type is the ordered cylindrical pores inheriting from the pores of SBA-15 and has a pore width of4.0~5.0 nm,the other type is the ordered quasi-hexagonal pores with a width of 3.0~4.0 nm produced by etching the pore walls of SBA-15.These two types of pores whose pore walls are built by the nitrogen doped carbon layers resulted by the CVD and thus it actually makes the dual nitrogen-doped interfaced OPC(DN-OPC).Meanwhile,DN-OPC contains a few of micropores and a large SSA of 1430 m~2/g.This dualordered pores and dual nitrogen-doped interfaces cannot only facilitate mass transport but also utilize the active sites of DN-OPC for ORR.Therefore,as metal-free ORR catalyst,DN-OPC exhibits a good activity close to commercial Pt/C catalyst,and an excellent durability and methanol tolerance.

Surfactant protein C dysfunction with new clinical insights for diffuse alveolar hemorrhage and autoimmunity

Importance:Surfactant protein C(SP-C)dysfunction is a rare disease associated with interstitial lung disease.Early therapies may improve outcomes but the diagnosis is often delayed owing to variability of manifestations.Objective:To investigate the manifestations and outcomes of SP-C dysfunction.Methods:We retrospectively analyzed the records of five pediatric patients who were diagnosed with SP-C dysfunction between February 2014 and April 2017 at Beijing Children's Hospital.Results:The five patients included two boys and three girls with a median age at diagnosis of 1.3 years.All patients presented with interstitial lung disease and had a heterozygous SFTPC mutation,including an I73T mutation in three patients,a V39L mutation in one patient,and a Y 104H mutation in one patient.In addition to common respiratory manifestations,hemoptysis and anemia were observed in one patient with the I73T mutation.Elevated levels of autoantibodies and a large number of hemosiderin-laden macrophages in bronchoalveolar lavage fluid were found in two patients with the I73T mutation,suggesting the presence of diffuse alveolar hemorrage and autoimmunity.Chest high-resolution computed tomography features included ground-glass opacities,reticular opacities,cysts,and pleural thickening.Transbronchial lung biopsy was performed in one patient with the I73T mutation,which revealed the presence of some hemosiderin-laden macrophages in alveolar spaces.All patients received treatment with corticosteroids;two received combined treatment with hydroxychloroquine.During follow-up,the two patients who received hydroxychloroquine showed improved symptoms;of the remaining three patients,two died after their families refused further treatment,while the final patient was lost to follow-up.Interpretation:This is the first report to describe a new phenotype of diffuse alveolar hemorrhage with autoimmunity in patients with I73T SFTPC mutation.Treatment with hydroxychloroquine should be considered for patients with SP-C dysfunction.

Clinical characteristics and prognoses of pulmonary mucormycosis in four children

Importance:Pulmonary mucormycosis is life threatening and carries a poor prognosis.Identification of factors that improve prognosis is urgently necessary.Objective:To analyze the clinical features and outcomes of pulmonary mucormycosis in children.Methods:A retrospective analysis of clinical data of four cases with pulmonary mucormycosis was conducted in Beijing Children's Hospital from January 2017 to December 2018.Results:Underlying diseases were identified in all four cases(diabetes in three individuals and a hematological malignancy in one individual).The predominant clinical manifestations were fever,cough,chest pain and hemoptysis.Imaging features included consolidation or nodules with cavities.All four cases were treated with liposomal amphotericin B,one case underwent lobectomy,and three cases received a full course ofposaconazole.All four cases were cured.Interpretation:Patients with pulmonary mucormycosis often have underlying diseases.Imaging features are relatively characteristic.Treatment with liposomal amphotericin B at an early stage and a sufficient course of posaconazole for maintenance significantly improves prognosis.

Clinical significance of interventional therapeutic bronchoscopy combined with bronchial arterial embolization in the treatment of hypervascular primary airway tumors in children

Importance Pediatric hypervascular primary airway tumors are progressive,fatal lesions with a low incidence,and the disease is often more serious than that in adults.Objective To evaluate the clinical efficacy and safety of interventional therapeutic bronchoscopy combined with conservative treatment and bronchial arterial embolization in children with primary airway tumors.Methods We retrospectively analyzed the clinical data of four pediatric patients with hypervascular primary airway tumor between 2017 and 2019 at Beijing Children’s Hospital.Results Two patients were low-grade bronchial mucoepidermoid carcinoma,one patient was pleomorphic adenoma,and one was bronchial leiomyoma.Interventional therapeutic bronchoscopy combined with bronchial arterial embolization was used for treatment(all four patients received general anesthesia).The tumors were safely resected in all patients via interventional bronchoscopy.There were no severe complications related to the procedures.All patients were followed up for 5–12 months,and one low-grade bronchial mucoepidermoid carcinoma recurred.Interpretation Interventional therapeutic bronchoscopy combined with bronchial arterial embolization appears to be a safe and efficient therapeutic method associated with less trauma and fewer complications,including no serious adverse events,in children with hypervascular primary airway tumors without bronchus wall infiltration.

Destruction of 4-phenolsulfonic acid in water by anodic contact glow discharge electrolysis

Destruction of 4-phenolsulfonic acid （4-PSA） in water was carded out using anodic contact glow discharge electrolysis. Accompanying the decay of 4-PSA, the amount of total organic carbon （TOC） in water correspondingly decreased, while the sulfonate group of 4- PSA was released as sulfate ion. Oxalate and formate were obtained as minor by-products. Additionally, phenol, 1,4-hydroquinone, hydroxyquinol and 1,4-benzoquinone were detected as primary intermediates in the initial stages of decomposition of 4-PSA. A reaction pathway involving successive attacks of hydroxyl and hydrogen radicals was assumed on the basis of the observed products and kinetics. It was revealed that the decay of both 4-PSA and TOC obeyed a first-order rate law. The effects of different Fe ions and initial concentrations of 4-PSA on the degradation rate were investigated. It was found that the presence of Fe ions could increase the degradation rate of 4-PSA, while initial concentrations lower than 80 mmol/L had no significant effect on kinetic behaviour. The disappearance rate of 4-PSA was significantly affected by pH.