Expression, purification, crystallization, and diffraction analysis of a selenomethionyl lipase Lip8 from Yarrowia lipolytica.

Yarrowia lipolytica is a nonconventional model micro-organism with multiple biotechnological applications. It is also considered to be an excellent producer for lipase. Genome survey shows that Y. lipolytica possesses various paralogs of genes coding for extracellular, cell-bound, and intracellular lipolytic enzymes. However, little structural information on these isoenzymes is available. With the aim to facilitate crystal structure solution of Lip8, one of the most valuable lipases from Y. lipolytica, a less conventional protein expression technique-selenomethionyl protein expression was used to produce recombinant selenomethionine (SeMet)-Lip8 in Escherichia coli. Finally, three Met residues of Lip8 were all substituted with SeMet. A total of 72 mg of SeMet-Lip8 was obtained from a liter of the SeMet medium. Using sodium acetate as a precipitant and ammonium sulfate as an additive, crystals of the SeMet-Lip8 with 1.9 Å were successfully cultured through hanging-drop vapor diffusion method. The estimated crystal dimensions were 0.11 × 0.11 × 0.14 mm2. The crystal belonged to the space group I4 with unit cell parameters a = b = 128.87 Å, c = 171.77 Å, α = ß = γ = 90°. It is the second member of lipase crystal family from Y. lipolytica. This work will provide a platform for further studying lipases from a structural insight.

Treatment of Chronic Plantar Fasciitis With Percutaneous Latticed Plantar Fasciotomy.

Plantar fasciitis, the most common cause of pain in the inferior heel, accounts for 11% to 15% of all foot symptoms requiring professional care among adults. The present study reports the results of a minimally invasive surgical treatment of chronic plantar fasciitis. All patients with plantar fasciitis who had undergone percutaneous latticed plantar fasciotomy at 3 clinical sites from March 2008 to March 2009 were included in the present study. The follow-up evaluations for this treatment were conducted using the Mayo clinical scoring system. We investigated 17 patients with recalcitrant chronic plantar fasciitis who had undergone this treatment within a follow-up period of ≥13 months. All procedures were performed in the clinic with the patient under local anesthesia. No wound infections or blood vessel or nerve damage occurred. At a mean follow-up period of 16.0 ± 2.29 (range 13 to 21) months, significant improvement was seen in the preoperative mean Mayo score (from 12.06 ± 2.54 to 89.76 ± 4.28, p < .001) and no patient had developed symptom recurrence. Also, none of the patients had developed complex regional pain syndrome. All patients were able to return to regular shoe wear by 3 weeks postoperatively. The technique of plantar fasciitis with percutaneous latticed plantar fasciotomy could be a promising treatment option for patients with recalcitrant chronic plantar fasciitis.

Application of CRISPR in evolution analysis, detecting and typing, virulence and antibiotic resistance regulation in food-borne pathogens / 生物工程学报

Clustered regularly interspaced short palindromic repeats (CRISPR) and its associated protein gene system can limit the horizontal gene transfer, thereby effectively preventing the invasion of foreign gene elements such as bacteriophages. CRISPR arrays of different bacteria are diverse. Based on the differences in the CRISPR system, this review summarizes the application of CRISPR in food-borne pathogen evolution analysis, detection and typing, virulence and antibiotic resistance in recent years. We also address bacterial detection typing method developed based on the characteristics of CRISPR arrays and the association of CRISPR with virulence and drug resistance of food-borne pathogens. The shortcomings of CRISPR in evolution, detection and typing, virulence and resistance applications are analyzed. In addition, we suggest standardizing CRISPR typing methods, improving and expanding the CRISPR database of pathogenic bacteria, and further exploring the co-evolution relationship between phages and bacteria, to provide references for further exploration of CRISPR functions.

SYTO/EB dyes for detection of skin viability / 中华外科杂志

<p><b>OBJECTIVE</b>the main purpose of this study is to develop an assay for detection of skin viability in situ.</p><p><b>METHODS</b>Two nucleic acid dyes, SYTO 13 and ethidium bromide (EB), are used to assess the viability of skin tissue. The viability of cells can be determined by different colors under fluorescence microscope. In this study, the recovery of skin restored at 4 degrees C for different periods is measured by SYTO/EB dyes and a type of indirect assessment, WST-1. Then both results are compared.</p><p><b>RESULTS</b>The results measured by two methods showed that the viability of skin tissue was nearly 30% after two weeks storage. At any point of experiment, the data from two methods have not obvious variance.</p><p><b>CONCLUSION</b>The assessment of skin viability by SYTO/EB is also quick, sensitive and convenient. At the same time the viability of any type of cells can be observed in situ. So it can be considered as an available method for detection of skin viability.</p>

ADHESION OF LYMPHOCYTES AND EOSINOPHILS IN PERIPHERAL BLOOD OF ASTHMA GUINEA PIG MODEL AND LUNG MICROVASCULAR ENDOTHELIAL CELLS / 解放军医学杂志

To explore the adhesion of peripheral blood lymphocytes and eosinophils and lung microvascular endothelial cells (LMEC) in asthma. Guinea pigs were divided into asthma model group and control group; the adhesion rates of isolated peripheral lymphocytes, eosinophils and the cultured LMEC monolayers were assayed.The mRNA expressions of VCAM 1 and eotaxin in LMEC were determined by RT PCR.The DNA binding activities of NF ?B and AP 1 of LMEC were detected by electrophoretic mobility shifts assay (EMSA). Under the stimulation with serum of asthma group:①the adhesion rates of lymphocytes, activated eosinophils and LMEC were significantly elevated( P

Analysis of Epidemic Situation of New Coronavirus Infection at Home and Abroad Based on Rescaled Range (R/S) Method

11.1 BackgroundThe outbreak of the new coronavirus infection broke out in Wuhan City, Hubei Province in December 2019, and has spread to 97 countries and regions around the world. Apart from China, there are currently three other severely affected areas, namely Italy, South Korea, and Iran. This poses a huge threat to Chinas and even global public health security, challenges scientific research work such as disease surveillance and tracking, clinical treatment, and vaccine development, and it also brings huge uncertainty to the global economy. As of March 11, 2020, the epidemic situation in China is nearing its end, but the epidemic situation abroad is in the outbreak period. Italy has even taken measures to close the city nationwide, with a total of 118,020 cases of infection worldwide. 1.2 MethodThis article selects the data of newly confirmed cases of COVID-19 at home and abroad as the data sample. Among them: the data of newly confirmed cases abroad is represented by Italy, and the span is from February 13 to March 10. The data of newly confirmed cases at home are divided into two parts: Hubei Province and other provinces except Hubei Province, spanning from January 23 to March 3, and with February 12 as the cutting point, it"s divided into two periods, the growth period and the recession period. The rescaled range (R / S) analysis method and the dimensionless fractal Hurst exponent are used to measure the correlation of time series to determine whether the time series conforms to the fractal Brownian motion, that is, a biased random process. Contrast analysis of the meaning of H value in different stages and different overall H values in the same stage. 1.3 ResultsBased on R / S analysis and calculated Hurst value of newly confirmed cases in Hubei and non-Hubei provinces, it was found that the H value of Hubei Province in the first stage was 0.574, which is greater than 0.5, indicating that the future time series has a positive correlation and Fractal characteristics; The H value in the second stage is 1.368, which is greater than 1, which indicates that the future epidemic situation is completely preventable and controllable, and the second stage has a downward trend characteristic, which indicates that there is a high probability that the future time series will decline. The H values of the first and second stages of non-Hubei Province are 0.223 and 0.387, respectively, which are both less than 0.5, indicating that the time series of confirmed cases in the future is likely to return to historical points, and the H value in the second stage is greater than that in the first stage, indicating that the time series of confirmed cases in the second stage is more long-term memory than the time series of confirmed cases in the first stage. The daily absolute number of newly confirmed cases in Italy was converted to the daily growth rate of confirmed cases to eliminate the volatility of the data. The H value was 1.853, which was greater than 1, indicating that the time series of future confirmed cases is similar to the trend of historical changes. The daily rate of change in cases will continue to rise. 1.4 ConclusionAccording to the different interpretation of the H value obtained by the R / S analysis method, hierarchical isolation measures are adopted accordingly. When the H value is greater than 0.5, it indicates that the development of the epidemic situation in the area has more long-term memory, that is, when the number of confirmed cases in the past increases rapidly, the probability of the time series of confirmed cases in the future will continue the historical trend. Therefore, it is necessary to formulate strict anti-epidemic measures in accordance with the actual conditions of various countries, to detect, isolate, and treat early to reduce the base of infectious agents.