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An Fe-embedded C2N monolayer as a promising single-atom catalyst for CO oxidation by O2 has been investigated based on first-principles calculations. It is found that the single Fe atom can be strongly trapped in the cavity of the C2N monolayer with a large adsorption energy of 4.55 eV and a high diffusion barrier of at least 3.00 eV to leave the cavity, indicating that Fe should exist in the isolated single-atom form. Due to the localized metal 3d orbitals near the Fermi level, the embedded Fe single-atom catalyst has a high chemical activity for the adsorption of CO and O2 molecules. CO oxidation by O2 on the catalyst would proceed via a two-step mechanism. The first step of the CO oxidation reaction has been studied via the Langmuir–Hinshelwood and Eley–Rideal mechanisms with energy barriers of 0.46 and 0.65 eV, respectively. The second step of the CO oxidation reaction follows the Eley–Rideal mechanism with a much smaller energy barrier of 0.24 eV. For both the steps, the CO2 molecules produced are weakly adsorbed on the substrates, suggesting that the proposed catalyst will not be poisoned by the generated CO2. Our results indicate that the Fe-embedded C2N monolayer is a promising single-atom catalyst for CO oxidation by O2 at low temperatures. [ABSTRACT FROM AUTHOR]

The issues of dissolution, agglomeration, CO poisoning and high cost associated with the use of Pt electrode for fuel cells have been driving the search for alternative electrocatalysts with better technical and economic performances. In this study, we report the synthesis of alternative macroporous Pd and La2O3 incorporated Pd network catalysts for electrochemical methanol oxidation reaction (MOR) in direct methanol fuel cells using eggshell membrane (ESM) template. The microstructural characterisation reveals a hierarchically ordered macroporous network of Pd reproducing the fibrous structure of ESM with average porosity and pore diameter of 39·5% and 2·33 μm respectively. The electrochemical characterisations show enhanced electrocatalytic activity, durability and CO tolerance of MOR by incorporating La2O3 into Pd network. The improved charge transfer and stability, along with lower cost promise the La2O3 added Pd to be robust catalysts in direct methanol fuel cells. [ABSTRACT FROM AUTHOR]

Data indicate that dietary thiamine supplementation can partly alleviate rumen epithelium inflammation and barrier function in goats fed a high-concentrate diet. The current work aimed to explore whether thiamine promotes rumen epithelium development by regulating carbohydrate metabolism during a long period of feeding high levels of concentrate. For the experiment, 24 female Boer goats (35.62 ± 2.4 kg of body weight) in parity 1 or 2 were allocated to 3 groups (8 goats per replicate) receiving a low-concentrate diet (concentrate:forage 30:70), a high-concentrate diet (HC; concentrate:forage 70:30), or a high-concentrate diet (concentrate:forage 70:30) supplemented with 200 mg of thiamine/kg of dry matter intake (HCT; concentrate:forage 70:30). On the last day of 12 wk, rumen fluid and blood samples were collected to measure ruminal parameters, endotoxin lipopolysaccharide, and blood inflammatory cytokines. Goats were slaughtered to collect ruminal tissue to determine differential metabolites, enzyme activities, and gene expression. Liquid chromatography-tandem mass spectrometry analysis revealed that the HCT group had significantly increased concentrations of d-glucose 6-phosphate, d-fructose 6-phosphate, glyceraldehyde 3-phosphate, thiamine pyrophosphate, oxaloacetate, acetyl-CoA, succinyl-CoA, sedoheptulose 7-phosphate, ribose 5-phosphate, and NADPH compared with the HC group. The pyruvate dehydrogenase, α-ketoglutarate dehydrogenase, and transketolase enzyme activities in the rumen epithelium of the HCT group were higher than those in the HC group. The plasma total antioxidant capacity values for the HCT group were greater than those for the HC group. The rumen epithelium ATP content in the HCT group was higher than that in the HC group. Compared with the HCT group, the HC group had a lower mRNA abundance of CCND1, CCNA2, CDK2, CDK4, CDK6, BCL2, PI3K, and AKT1. Taken together, the results suggest that dietary thiamine supplementation could ameliorate disorders in the tricarboxylic acid cycle and the pentose phosphate pathway induced by a long-term high-concentrate diet and could promote rumen epithelial growth., (Copyright © 2021 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.)

This case report presents the diagnosis and treatment of a case with subcutaneous sparganosis.

Objective: To investigate the clinical implications of p16 gene deletion in adult Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph(+) ALL) . Methods: Retrospective analysis of clinical, immunophenotypic, cytogenetics, molecular characteristics and prognosis of 80 newly diagnosed Ph(+) ALL patients with p16 deletion. Results: Of 80 adult Ph(+) ALL, the prevalence of p16 gene deletion was 31.3%. p16 gene deletion carriers frequently accompanied with high WBC counts (WBC≥30×10(9)/L) and CD20 expression. The incidence of complex chromosome abnormality in p16 gene deletion group was higher than that in non-deletion group, with alternations in chromosome 7, 8, 19 and der (22) more frequently observed. There was no difference occurred between patients with or without p16 gene deletion in complete remission (CR) rate following induction chemotherapy combined with tyrosine kinase inhibitors (TKIs) . However, after three cycles of chemotherapy, the MMR and CMR rate in the p16 gene deletion group was lower than patients with wild-type p16 gene ( P =0.034, P =0.036) . The p16 gene deletion patients showed no significant differences in MMR, CMR and relapse rate between Imatinib or Dasatinib plus chemotherapy ( P >0.05) . Deletion of p16 gene was significantly associated with poor outcomes including worse overall survival (OS) (37.1% vs 54.1%, P =0.037) , lower disease free-survival (DFS) (12.4% vs 45.9%, P =0.026) , and increased cumulative incidence of relapse ( P =0.033) . Among the 25 patients with p16 deletion, 14 underwent allo-HSCT and the median survival was 21 months, better than that of patients received chemotherapy alone (12 months) ( P =0.030) . Conclusion: This study indicated that deletion of p16 was associated with poor prognosis in adult Ph(+) ALL, and the utility of second-generation TKI (Dasatinib) does not necessarily have an edge on efficacy over Imatinib, but allo-HSCT has the potential of elongating life expectancy. It is an important significance to define the status of p16 in Ph(+) ALL for predicting prognosis and guiding therapy decision-making.

Objective: To analyze the association of cytogenetic abnormalities with the prognosis of chronic myeloid leukemia (CML) patients in tyrosine kinase inhibitors (TKI) era. Methods: Karyotype analysis of chromosome G-banding was carried out in 387 newly diagnosed CML patients by short-term culture of bone marrow cells. The correlation of cytogenetic abnormalities and CML progression was explored in combination with ABL tyrosine point mutations. Result: Of 387 patients with positive BCR-ABL fusion gene assayed by fluorescence in situ hybridization (FISH) technique, 94.1% (364/387) patients were Ph positive and 5.9% (23/387) Ph negative; 320 patients (87.9%) had a translocation t (9;22) (q34;q11) and 5 (1.4%) a variant translocation t (v;22) . Additional cytogenetic aberrations (ACA) at diagnosis were found in 10.7% (39/387) Ph(+) patients, major route ACA in 22 (56.4%) cases and minor route ACA in 15 (38.5%) cases and 2 patients (5.1%) lacked the Y chromosome (-Y) ; 23.4% (71/303) patients occurred ACA during TKI treatment and the most frequent abnormalities were abnormal chromosome numbersd, which were likely associated with high proportion of disease progression ( χ (2)=168.21, P< 0.001) and ABL tyrosine point mutations ( χ (2)=29.04, P< 0.001) . Newly diagnosed CML-CP patients with t (9;22) (q34;q11) had a longer event-free survival (EFS) and disease-free survival (DFS) rates than that of patients with ACA ( P =0.037; P=0.003) , while the overall survival (OS) had no significant differences ( P =0.209) . As for CML-CP patients that occurred ACA during TKI therapy would have a marked low OS, EFS and DFS (all P <0.001) compared with no ACA occurred patients. Survival of advanced patients that occurred ACA were dramatically reduced. Conclusion: ACA often emerged during the disease progress in CML patients, regular and timely detection of chromosomes karyotype and ABL tyrosine point mutations during TKI treatment was important for therapeutic evaluation, progress and prognosis of CML.

Epidemiological survey was conducted, according to diagnostic standard from WHO-MONICA project, on stroke events in 16 provinces of China. There were significant differences in geographical distribution of morbidity and mortality of stroke events. The morbidity and mortality were higher in northern China than in southern China (P < 0.001). The differences of morbidity varied from 11 to 14 times. The morbidity and mortality were higher in man than in woman (P < 0.01 or P < 0.05) and were higher in rural areas than in cities. The geographical differences in the morbidity and mortality for stroke may be related to many factors, and may be in parallel with the hypertension prevalence rate, which was higher in northern China than in Southern China. The age of patients with stroke was younger in northern China than in southern China (P < 0.01). The frequency of cerebral hemorrhage was higher in southern China than in northern China.

We analyzed the data on stroke surveillance from 1985 to 1989 in Beijing. The results showed the annual average incidence rate was 189/100,000 and the first incidence rate was 134/100,000 in the population aged 25-74. The age standardized rates for both of them were 223/100,000 and 158/100,000 respectively. The incidence rate for male was 1.5 times as high as that for female. The incidence rate in rural area was 1.3 times as high as that in urban area. The incidence rates increased with age. The seasonal distribution of stroke incidence showed that it was the highest in winter and the lowest in summer. The trend of incidence from 1985 to 1989 was relatively steady. It is urgent to conduct the prevention of cerebrovascular disease (CVD) in Beijing.

Synthesis and bioactivities of new antagonists of luteinizing hormone releasing hormone (LHRH) with novel unnatural amino acids at position five are reported. Most of them showed some antiovulatory activity at 0.5 microgram/rat and two of them inhibited ovulation completely at 1 microgram/rat using saline as vehicle.

The origin of free cells in urine is difficult to determine in the absence of cellular casts. Using fluorescein-conjugated antibody to human Tamm-Horsfall protein (THP), it examines THP coating of free cells in urine (THP-CFC), that could be distinguished between renal parenchymal disease (RPD) and lower urinary tract disease (LUTD). We had examined THP-CFC in urine of the patients with all kinds of RPD, renal or ureteral stone (RUS) and LUTD. The percentage of THP-CFCs was 0% in healthy volunteers (n = 34), 0-8% in LUTD group (n = 14), 86.3% in glomerulonephritis and SLE nephritis group (n = 29), 80.8% in chronic intertitial nephritis group (n = 26), 0-10% in RUS group (n = 14). The research results suggest that the percentage of THP-CFCs between the RPD and LUTD or RUS had a significant difference. The presence of THP-CFC in RPD and its absence in LUTD suggests that this simple test may be of use in differentiating RPD from LUTD.

Five new antagonists of luteinizing hormone releasing hormone (LHRH) containing novel unnatural amino acids at position six are reported. They are very effective in the rat antiovulatory assay. Using saline as vehicle, antagonist-[N-Ac-D-2-Nal1, D-4-Cl-Phe2, D-3-Pal3, Arg5, D-A26, D-Ala10]-LHRH inhibited ovulation completely at 1 micrograms/rat and three of the other antagonists showed some antiovulatory activity at 0.5 micrograms/rat.

Aminoacylase from Aspergillus oryzae was adsorbed on functionallized macroporous copolymers where the enzyme showed excellent catalyzing activity and operation stability. Various factors which effect the activity of the immobilized aminoacylase such as temperature, pH and ionic strength were investigated. The continuous operation of the enzyme immobilized on macroporous copolymers was compared with that of the enzyme immobilized on DEAE-Sephadex.

The aminoacylase from Aspergillus oryzae was adsorbed on polymer carriers where the enzyme showed excellent catalyzing activity and operating stability. It was found that the pore structure and functional group were the basic factors which affected the activity of the adsorbed enzyme. The hydrophobility of the carriers did not play an important role in the enzymatic resolution. Various factors, such as percentage and nature of cross-linking agent, porogenic agents and functionalizing agents which controlled the pore structure and properties of the polymer carriers during their preparation, were investigated and relationship between the activity of the adsorbed aminoacylase and the carrier structure was also discussed.