An extracellular β-xylosidase from the thermophilic fungus
Paecilomyces thermophila J18 was purified 31.9-fold to homogeneity with a recovery yield of 2.27% from the cell-free culture supernatant. It ...appeared as a single protein band on SDS–PAGE with a molecular mass of approx 53.5
kDa. The molecular mass of β-xylosidase was 51.8
kDa determined by Superdex 75 gel filtration. The enzyme was a glycoprotein with a carbohydrate content of 61.5%. It exhibited an optimal activity at 55
°C and pH 6.5, respectively. The enzyme was stable in the range of pH 6.0–9.0 and at 55
°C. The purified enzyme hydrolyzed xylobiose and higher xylooligosaccharides but was inactive against xylan substrates. It released xylose from xylooligosaccharides with a degree of polymerization ranging between 2 and 5. The rate of xylose released from xylooligosaccharides by the purified enzyme increased with increasing chain length. It had a
K
m
of 4.3
mM for
p-nitrophenol-β-
d-xylopyranoside and was competitively inhibited by xylose with a
K
i
value of 139
mM. Release of reducing sugars from xylans by a purified xylanase produced by the same organism increased markedly in the presence of β-xylosidase. During 24-hour hydrolysis, the amounts of reducing sugar released in the presence of added β-xylosidase were about 1.5–1.73 times that of the reaction employing the xylanase alone. This is the first report on the purification and characterization of a β-xylosidase from
Paecilomyces thermophila.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Gestational diabetes mellitus (GDM) is associated with an increased risk of suffering diverse adverse pregnancy outcomes, threating maternal and child health seriously, with an increasing incidence ...rate year by year. However, the exact cause of GDM is still unknown. Prospective cohort studies obtain data through follow-up, which is helpful to clarify the causal relationship, so as to draw more accurate and reliable conclusions. In recent years, numerous prospective cohort studies on the GDM have emerged. This article elaborates along the occurrence and development process of GDM, in order to provide useful reference for the establishment of relevant high-quality prospective cohort studies in China.
To investigate the incidence of postoperative complications in Chinese patients with gastric or colorectal cancer, and to evaluate the risk factors for postoperative complications.
This was a ...national, multicenter, prospective, registry-based, cohort study of data obtained from the database of the Prevalence of Abdominal Complications After Gastro- enterological Surgery (PACAGE) study sponsored by the China Gastrointestinal Cancer Surgical Union. The PACAGE database prospectively collected general demographic characteristics, protocols for perioperative treatment, and variables associated with postoperative complications in patients treated for gastric or colorectal cancer in 20 medical centers from December 2018 to December 2020. The patients were grouped according to the presence or absence of postoperative complications. Postoperative complications were categorized and graded in accordance with the expert consensus on postoperative complications in gastrointestinal oncology surgery and Clavien-Dindo gradin
In this work, the Cu electrodeposition was carried out for the filling of through silicon via (TSV) using an additive-free Cu electrolyte and periodic pulse reverse (PPR) current. It was attempted to ...understand the filling mechanism by PPR plating and then to explore a potential solution for void-free filling in easy electrolytes. The filling results showed that the void size was continually reduced as decreasing current density. A void-free filling was obtained at low current density. During the Cu growth process, a "V" shape filling structure occurred at the upper of the via and the ratio of this structure increased with the decrease of current density. The electrochemical analyzes results demonstrated that at low current density, the potential during forward deposition was more uniform along the depth, and during reverse pulse the potential difference between the shallow and deep location was larger than that at high current density. This result implied that at low current density the reverse pulse played a strong suppression effect that contributed to the "V" shape growth. A competitive growth model between the bottom reversed "V" structure and the upper "V" structure was proposed to explain the void-free filling mechanism in PPR plating process.
To investigate the rate of periprosthetic joint infection (PJI) revision surgeries and clinical information of hip-/knee- PJI cases nationwide from 2015 to 2017 in China.
An epidemiological ...investigation. A self-designed questionnaire and convenience sampling were used to survey 41 regional joint replacement centers nationwide from November 2018 to December 2019 in China. The PJI was diagnosed according to the Musculoskeletal Infection Association criteria. Data of PJI patients were obtained by searching the inpatient database of each hospital. Questionnaire entries were extracted from the clinical records by specialist. Then the differences in rate of PJI revision surgery between hip- and knee- PJI revision cases were calculated and compared.
Total of 36 hospitals (87.8%) nationwide reported data on 99 791 hip and knee arthroplasties performed from 2015 to 2017, with 946 revisions due to PJI (0.96%). The overall hip-PJI revision rate was 0.99% (481/48 574), and it was 0.97% (135/13 963), 0.97% (153/15 730) a
ABSTRACT
We report the phase-connected timing ephemeris, polarization pulse profiles, Faraday rotation measurements, and Rotating-Vector-Model (RVM) fitting results of 12 millisecond pulsars (MSPs) ...discovered with the Five-hundred-meter Aperture Spherical radio Telescope (FAST) in the Commensal Radio Astronomy FAST survey (CRAFTS). The timing campaigns were carried out with FAST and Arecibo over 3 yr. 11 of the 12 pulsars are in neutron star–white dwarf binary systems, with orbital periods between 2.4 and 100 d. 10 of them have spin periods, companion masses, and orbital eccentricities that are consistent with the theoretical expectations for MSP–Helium white dwarf (He WD) systems. The last binary pulsar (PSR J1912−0952) has a significantly smaller spin frequency and a smaller companion mass, the latter could be caused by a low orbital inclination for the system. Its orbital period of 29 d is well within the range of orbital periods where some MSP–He WD systems have shown anomalous eccentricities, however, the eccentricity of PSR J1912−0952 is typical of what one finds for the remaining MSP–He WD systems.
Cypermethrin contamination was a potential threat to soil organisms. In the present work, reproductive damage in earthworms (Amynthas corticis) exposed to cypermethrin was investigated. It was found ...that earthworms could absorb and accumulate residual cypermethrin in soil, and also earthworm activities helped accelerate the degradation of cypermethrin in soil. The accumulation of cypermethrin in earthworms induced sperm damage, and cypermethrin not only caused the imbalance of calcium homeostasis in earthworm sperm cells by inhibiting earthworm sperm Ca2+-ATP and Ca2+-Mg2+-ATP enzyme activities but also caused barriers in acrosome reaction. It also affected sperm energy supply of earthworms by inhibiting the activity of Na+-K+-ATPase and Mg2+-ATPase of earthworm sperm. Meanwhile, the inhibition of acrosome enzyme activity of earthworm sperm by cypermethrin led to hinder fertilization and reduced cocoon production of earthworms, and the damage of cypermethrin to sperm of earthworm was a significant cause of its reproductive toxicity. The results of the evaluation of IBR index showed that reproductive toxicity of cypermethrin to earthworms reduced with the increasing time. The decreased reproductive toxicity of cypermethrin to earthworms at the later stage of exposure (42–56 d) might be due to a combination of reduced absorption of cypermethrin in soil by earthworms, decreased accumulation of cypermethrin in the body, and improved sperm capacitation.
•Earthworms could absorb and accumulate residual cypermethrin in soil.•Earthworm activities helped accelerate the degradation of cypermethrin in soil.•Damage to earthworm spermatozoa by cypermethrin was a significant cause of its reproductive toxicity.•Changes in sperm viability, acrosome enzyme activity and Ca2+-ATPase activity of earthworms indicated reproductive damage in earthworms.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Natural fragmentation of steel cylinders with different charge sizes is investigated, and the correlation of different cylinders is proposed. The Mott fragment distribution has some obvious ...shortcomings, including the difficulty of accurately determining the number of fragments. Besides, there is no unified and convenient method to describe the fragmentation behavior of shells with different structures. The results show that the fragmentation behavior of the cylinder is self-similar statistically and can be characterized by a new integrated linear formula
. Due to the existence of the end face and the charge clearance, the fragmentation performance of the cylinder is reduced to a constant value, and the effect of the wall thickness is small. The influence of the end face and charge clearance on fragmentation is investigated by 3D simulations, and the numerical results ensure good validation of the experimental data.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Objective
To investigate the effect of add-on exenatide to insulin on glycemic excursion and the counter-regulatory hormone in response to hypoglycemia in patients with type 1 diabetes mellitus ...(T1DM).
Methods
30 patients with T1DM were recruited and randomly assigned to exenatide + insulin-treated group (group 1,
n
= 15) or insulin-only-treated group (group 2,
n
= 15) for 4 weeks. All patients had continuous glucose monitor system (CGMS) applied at before (week-0) and after (week-4) treatment to evaluate the glycemic variability. All patients had an arginine-stimulated test at before and after treatment. Six patients from each group also had hypoglycemic clamp test to assess counter-regulatory hormone level.
Results
Patients in the exenatide group had significant reductions in body weight, body mass index (BMI), total insulin dose, bolus insulin dose, fructosamine, and glycemic excursion after 4 weeks’ treatment. Compared with patients in group 2, the mean amplitude of glycemic excursion (MAGE) and coefficient of variation (CV) of exenatide group decreased significantly. Similarly, a significant decrease of glucagon (GLC) in the arginine-stimulated test was found in group 1. No significant changes of GLC, growth hormone (GH), cortisol (COR), epinephrine (E), and norepinephrine (NE) were found in both groups during hypoglycemia clamp test. However, patients who had residual islet function in group 1 showed an upward trend of basic C-peptide (C-P) and GLC during the hypoglycemia period.
Conclusion
Although exenatide could inhibit glucagon secretion during euglycemia or hyperglycemia in patients with T1DM, it has no effect on GLC and counter-regulatory hormones during hypoglycemia clamp in patients with no functional residual islet test.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
