OBJECTIVES: The coronavirus disease (COVID-19) outbreak has catastrophically threatened public health worldwide and presented great challenges for clinicians. To date, no specific drugs are available against severe acute respiratory syndrome coronavirus 2. Mesenchymal stem cells (MSCs) appear to be a promising cell therapy owing to their potent modulatory effects on reducing and healing inflammation-induced lung and other tissue injuries. The present pilot study aimed to explore the therapeutic potential and safety of MSCs isolated from healthy cord tissues in the treatment of patients with COVID-19. METHODS: Twelve patients with COVID-19 treated with MSCs plus conventional therapy and 13 treated with conventional therapy alone (control) were included. The efficacy of MSC infusion was evaluated by changes in oxygenation index, clinical chemistry and hematology tests, immunoglobulin (Ig) levels, and pulmonary computerized tomography (CT) imaging. The safety of MSC infusion was evaluated based on the occurrence of allergic reactions and serious adverse events. RESULTS: The MSC-treated group demonstrated significantly improved oxygenation index. The area of pulmonary inflammation decreased significantly, and the CT number in the inflammatory area tended to be restored. Decreased IgM levels were also observed after MSC therapy. Laboratory biomarker levels at baseline and after therapy showed no significant changes in either the MSC-treated or control group. CONCLUSION: Intravenous infusion of MSCs in patients with COVID-19 was effective and well tolerated. Further studies involving a large cohort or randomized controlled trials are warranted.

RESUMO OBJETIVO: Investigar o efeito protetor e o mecanismo da dexmedetomidina (Dex) na lesão perioperativa do miocárdio em doentes com dissecação aórtica Tipo A de Stanford (AD). MÉTODOS: Oitenta e seis pacientes com o Tipo A de Stanford foram aleatoriamente divididos em Dex e grupos de controle, 43 casos em cada grupo. Durante a cirurgia, o grupo de controle recebeu a anestesia de rotina, e o grupo Dex recebeu tratamento Dex baseado na anestesia de rotina. A frequência cardíaca (AR) e a pressão arterial média (MAP) foram registradas no momento anterior ao Dex carregar (t0), 10 minutos após o Dex carregar (t1), incisão cutânea (t2), serragem de esterno (t3), antes do bypass cardiopulmonar (t4), extubação (t5) e fim da cirurgia (t6). Os índices de sangue foram determinados no momento antes da indução da anestesia (T0) e no pós-operatório 12 horas (T1), 24 horas (T2), 48 horas (T3) e 72 horas (T4). RESULTADOS: Em T2 e t3, o RH e o MAP do grupo Dex foram inferiores ao grupo de controle (p<0,05). Em comparação com o grupo de controle, no grupo Dex em T1, T2 e T3, os níveis séricos de creatina quinase-MB, troponina-I, proteína C-reativa e necrose do fator-α do tumor diminuíram, o nível interleucina-10 aumentou, o desalinhamento total do superóxido sérico e a capacidade antioxidante total aumentaram e os níveis de mielopeperóxido e malondialdeído diminuíram (todos p<0,05). CONCLUSÃO: O tratamento com Dex pode aliviar a lesão do miocárdio perioperativo em doentes com o Tipo A de Stanford por resistência à resposta inflamatória e ao estresse oxidativo.

SUMMARY OBJECTIVE: To investigate the protective effect and mechanism of dexmedetomidine (Dex) on perioperative myocardial injury in patients with Stanford type-A aortic dissection (AD). METHODS: Eighty-six patients with Stanford type-A AD were randomly divided into Dex and control groups, with 43 cases in each group. During the surgery, the control group received the routine anesthesia, and the Dex group received Dex treatment based on routine anesthesia. The heart rate (HR) and mean arterial pressure (MAP) were recorded before Dex loading (t0), 10 min after Dex loading (t1), at the skin incision (t2), sternum sawing (t3), before cardiopulmonary bypass (t4), at the extubation (t5), and at end of surgery (t6). The blood indexes were determined before anesthesia induction (T0) and postoperatively after 12h (T1), 24h (T2), 48h (T3), and 72h (T4). RESULTS: At t2 and t3, the HR and MAP in the Dex group were lower than in the control group (P < 0.05). Compared with the control group, in the Dex group at T1, T2, and T3, the serum creatine kinase-MB, cardiac troponin-I, C-reactive protein, and tumor necrosis factor-α levels were decreased, and the interleukin-10 level, the serum total superoxide dismutase, and total anti-oxidant capability increased, while the myeloperoxidase and malondialdehyde levels decreased (all P < 0.05). CONCLUSIONS: Dex treatment may alleviate perioperative myocardial injury in patients with Stanford type-A AD by resisting inflammatory response and oxidative stress.

ABSTRACT Two experiments were conducted to evaluate the effects of β-mannanase on egg production performance, egg quality, intestinal microbiota, viscosity, and ammonia concentration in laying hens. In Exp. 1, two hundred and seventy 30-wk-old Hy-Line Brown laying hens were assigned to 6 diets arranged in a 3 × 2 factorial of three levels of MEn and CP [(a corn-soybean meal based diet (HEHP), a diet containing 50 kcal of MEn/kg and 1.0% less energy and CP than the HEHP (MEMP), and a diet containing 80 kcal of MEn/kg and 1.5% less energy and CP than HEHP (LELP)], and β-mannanase supplementation (0 or 0.04%). In Exp. 2, A total of two hundred and sixteen62-wk-old Hy-Line Brown laying hens were assigned to 6 dietary treatments in a 3 × 2 factorial arrangement. In Exp. 1, β-mannanase supplementation increased egg production rate in hens fed LELP diet, but not in those fed HEHP or MEMP diet (interaction, p<0.01), and the interaction was significant (p<0.01) for egg mass. β-mannanase supplementation decreased (p<0.05) ammonia concentration. In Exp. 2, the supplementation of β-mannanase increased egg production rate and egg mass in hens fed LELP diet, whereas no differences were found in those fed HEHP or MELP diet (interaction, p<0.01). The supplementation of β-mannanase in a lower energy and protein diet resulted in similar production performance when compared to high-energy and high-protein diet during early and late stages of egg production.

ABSTRACT: Biological degumming is an eco-friendly, efficient, high-quality and low-cost method that has become the leading bast fiber degumming technology. However, bacterial strains with short degumming cycles, high gum removal rates and small fiber damage are few. To screen high quality microbial resources with bast-fiber biological degumming function, soil samples were collected from a continuously cultivated banana plantation and then used to be enriched by ramie and kenaf materials in turn. A selective pectin-degrading medium was used to screen for excellent bacteria. A dominant bacterial strain was identified by phenotypic and genotypic characteristics, and its biological degumming effects on ramie and kenaf were verified by a comprehensive evaluation system. Results showed that seven bacterial strains secreting pectinase were obtained and the largest hydrolysis circle with a diameter ratio H/C of 2.4 was produced by the bacterial strain hn1-1, which was preliminarily identified as the Bacillus cereus by colony morphological characteristics and 16S rDNA sequence (GenBank accession number: KX013542) cluster analysis. The fiber production of ramie and kenaf degummed by B. cereus hn1-1 for 10 h were 72 % and 76 %, the residual gum rates were 4 % and 5 %, respectively. These values satisfied the textile industry requirement of < 6 % residual gum rate. Therefore, an effective biological degumming bacterium, B. cereus, was identified using a pectin-hydrolysis selective medium through a simple, economical, and time-saving method. Furthermore, the biological degumming technology by B. cereus for ramie and kenaf had a short cycle, ideal removal gum rate, and high-quality and productive fiber output.

Background: The impact of enteral nutrition (EN) on surgical risk in Crohn's disease (CD) patients suffering from spontaneous intra-abdominal abscess (IAA) was evaluated. Methods: CD patients diagnosed with spontaneous IAA from 2008 to 2015 were included in the study. The impact of EN on surgical risk was evaluated using both univariate and multivariate analyses. Results: A total of 87 patients were enrolled, 66 (75.9%) were male. The mean age at the development of an abscess was 30.2 ± 10.1 years and the median duration of illness from CD diagnosis until the development of an abscess was three (2-6) years. After a median follow-up of 1.9 (1.1-2.9) years, surgical intervention was performed in 42 patients (48.3%). Patients treated with EN were less likely to require surgical intervention (26.1% vs 56.3%, p = 0.01). Multivariate analysis showed that EN was an independent protective factor for the risk of surgery with a hazard ratio of 0.27 (95% confidence interval: 0.11-0.65, p = 0.004) after adjusting for abdominal pain, history of abdominal surgery, concomitant intestinal stenosis and prior use of antibiotics within three months. Conclusions: Surgical intervention is common for CD patients with IAA. Appropriate application of EN may help obviate the need for surgical treatment.

Ramie (Boehmeria nivea and Boehmeria tenacissima) is a widely used fiber crop. Traditional water retting or chemical boiling method performed in order to extract ramie fiber seriously pollute the environment and severely damage the fiber, so biological method is the general trend of the fiber-extracting industry. Some strains (687), involving 26 genera and 43 species, were collected from the three samples, which produce hydrolyzed circles in the selective culture medium in order to detect the degumming effect and to compare the enzyme activity. Among these strains, 13 of them did not produce cellulase and had a ramie decreasing weight rate above 25 %, which were regarded as efficient ramie-degumming strains named from R1 to R13. R1 to R13 belonged to Amycolata autotrobutylicun, Bacillus subtilis, Clostridium acetobutylicum, Bacillus subtilis, Rhizobium leguminosarum, Bacteroides finegoldii, Streptomyces lividans, Bacillus amyloliquefaciens, Clostridium acetobutylicum, Pseudomonas brassicacearum, Bacillus pumilus, Bacillus licheniformis, Pectobacterium wasabiae respectively. Bacteroides sp., Rhizobium sp. and Pseudomonas sp. were firstly reported to be used in ramie-degumming. At the same time, the pectinase was the key enzyme in the ramie-degumming process.