Fucoxanthin is a natural marine xanthophyll and exhibits a broad range of biological activities. In the present study, a simple and efficient two-step method was used to purify fucoxanthin from the ...diatom,
. The crude pigment extract of fucoxanthin was separated by silica gel column chromatography (SGCC). Then, the fucoxanthin-rich fraction was purified using a hydrophile-lipophile balance (HLB) solid-phase extraction column. The identification and quantification of fucoxanthin were determined by high-performance liquid chromatography (HPLC) and electrospray ionization mass spectrometry (ESI-MS). This two-step method can obtain 92.03% pure fucoxanthin and a 76.67% recovery rate. In addition,
H and
C NMR spectrums were adopted to confirm the identity of fucoxanthin. Finally, the purified fucoxanthin exhibited strong antioxidant properties in vitro with the effective concentration for 50% of maximal scavenging (EC50) of 1,1-Dihpenyl-2-picrylhydrazyl (DPPH) and 2,2'-Azinobis-(3-ethylbenzthiazoline-6-sulphonate) (ABTS) free radicals being 0.14 mg·mL
and 0.05 mg·mL
, respectively.
Since the outbreak of 2019 novel coronavirus infection (2019-nCoV) in Wuhan City, China, by January 30, 2020, a total of 9692 confirmed cases and 15,238 suspected cases have been reported around 31 ...provinces or cities in China. Among the confirmed cases, 1527 were severe cases, 171 had recovered and been discharged at home, and 213 died. And among these cases, a total of 28 children aged from 1 month to 17 years have been reported in China. For standardizing prevention and management of 2019-nCoV infections in children, we called up an experts’ committee to formulate this experts’ consensus statement. This statement is based on
the Novel Coronavirus Infection Pneumonia Diagnosis and Treatment Standards (the fourth edition)
(National Health Committee) and other previous diagnosis and treatment strategies for pediatric virus infections. The present consensus statement summarizes current strategies on diagnosis, treatment, and prevention of 2019-nCoV infection in children.
Humans are adversely affected by exposure to cadmium (Cd) as it induces oxidative stress which damages kidneys, bones pulmonary tissues, liver, cardiovascular, immune, reproductive systems and ...influences endocrine secretions. In the present study tubotaiwine treatment regulated systolic, diastolic and mean arterial blood pressure of the Cd exposed rats. Tubotaiwine significantly promoted vascular responsiveness to Phe, ACh and SNP and reversed Cd mediated decrease in eNOS and increase in iNOS expression. Treatment of the Cd exposed rats with tubotaiwine reduced number of smooth muscle cells, decreased collagen content and promoted content of elastin in aortic artery walls. Tubotaiwine treatment significantly suppressed Cd-induced increase in MMP-2 and MMP-9 in rat aortic artery tissues. Increase in O
2–
, urinary nitrate/nitrite, MDA, carbonyl level and decrease in GSH production in rat blood and thoracic aorta tissues were effectively reversed by tubotaiwine treatment. Tubotaiwine treatment of the rats significantly reduced Cd-induced increase in blood, liver, heart and kidney tissue Cd content in dose dependent manner. Thus, tubotaiwine suppresses Cd induced hypertension in rats by reducing arterial stiffness, inhibition of oxidative stress and increasing vascular remodeling. Therefore, tubotaiwine has beneficial effect on Cd induced hypertension in rats and may be developed as a potential candidate for treatment of hypertension.
In the control of plant diseases, biocontrol has the advantages of being efficient and safe for human health and the environment. The filamentous fungus
and its closely related species can inhibit ...the growth of many phytopathogenic fungi, and have been developed as commercial biocontrol agents for decades. In this review, we summarize studies on
species complex from the perspective of strain improvement. To elevate the biocontrol ability, the production of extracellular proteins and compounds with antimicrobial or plant immunity-eliciting activities need to be enhanced. In addition, resistance to various environmental stressors should be strengthened. Engineering the gene regulatory system has the potential to modulate a variety of biological processes related to biocontrol. With the rapidly developing technologies for fungal genetic engineering,
strains with increased biocontrol activities are expected to be constructed to promote the sustainable development of agriculture.
In the past 10 years, the treatment and restoration of soil and water bodies contaminated by mercury and other heavy metals have received unprecedented attention and support from China’s ...environmental protection authorities. The search for low-cost and high-efficiency adsorbents has become one of the research hotspots in this field. In this paper, a simple and environment-friendly method was used to graft 3-mercaptopropyl trimethoxysilane on the surface of palygorskite. The synthesized mercaptofunctionalized palygorskite (M-PAL) was characterized by XRD, FT-IR, BET and SEM-EDS, respectively, and its adsorption conditions, adsorption models and thermodynamic parameters for Hg
2+
were systematically investigated. The experimental results indicated that the saturated adsorption capacity of Hg
2+
on the M-PAL could reach 203.4 mg·g
−1
, within 120 min at pH 4 and 298 K. By analyzing the experimental data of adsorption kinetics and thermodynamics, it was found that the adsorption process of Hg
2+
conformed to the pseudo-second-order kinetic model, which belonged to chemical adsorption of the rate-controlled step; the Langmuir model better described the adsorption isotherm. The thermodynamic parameters obtained (Δ
H
=29.95 kJ·mol
−1
, Δ
S
=103.09 J·mol
−1
·K
−1
and Δ
G
<0) show that the whole process is a spontaneous endothermic process. When the concentration of Na
+
, K
+
, Ca
2+
, Mg
2+
, Cl
−
, NO
3
−
, H
2
C
2
O
4
and C
6
H
8
O
7
was 200 times that of Hg
2+
, although these organic acids had a slightly greater effect on the adsorption of Hg
2+
on mercaptofunctionalized palygorskite than inorganic ions, the adsorption capacity remained above 185 mg·g
−1
. The adsorption products could be still stable in simulated acid rain with pH 3, 4, 5, 6, 7 and oxalic acid solution with concentration of 1, 2, 3, 4 and 5 mmol·L
−1
, and the desorption rates were about 3%. Through XPS analysis, the specific coordination of Hg
2+
with the S atom on the surface of M-PAL was confirmed.
Filamentous fungus Penicillium oxalicum produces diverse lignocellulolytic enzymes, which are regulated by the combinations of many transcription factors. Here, a single-gene disruptant library for ...470 transcription factors was constructed and systematically screened for cellulase production. Twenty transcription factors (including ClrB, CreA, XlnR, Ace1, AmyR, and 15 unknown proteins) were identified to play putative roles in the activation or repression of cellulase synthesis. Most of these regulators have not been characterized in any fungi before. We identified the ClrB, CreA, XlnR, and AmyR transcription factors as critical dose-dependent regulators of cellulase expression, the core regulons of which were identified by analyzing several transcriptomes and/or secretomes. Synergistic and additive modes of combinatorial control of each cellulase gene by these regulatory factors were achieved, and cellulase expression was fine-tuned in a proper and controlled manner. With one of these targets, the expression of the major intracellular β-glucosidase Bgl2 was found to be dependent on ClrB. The Bgl2-deficient background resulted in a substantial gene activation by ClrB and proved to be closely correlated with the relief of repression mediated by CreA and AmyR during cellulase induction. Our results also signify that probing the synergistic and dose-controlled regulation mechanisms of cellulolytic regulators and using it for reconstruction of expression regulation network (RERN) may be a promising strategy for cellulolytic fungi to develop enzyme hyper-producers. Based on our data, ClrB was identified as focal point for the synergistic activation regulation of cellulase expression by integrating cellulolytic regulators and their target genes, which refined our understanding of transcriptional-regulatory network as a "seesaw model" in which the coordinated regulation of cellulolytic genes is established by counteracting activators and repressors.
Primary ciliary dyskinesia (PCD) is a recessive genetic disorder of motile cilia with substantial genetic and phenotypic heterogeneity. Clinical features of PCD vary from one patient to another, and ...no single test has the sensitivity and specificity to accurately diagnose PCD. Genetic testing combined with other auxiliary tests can facilitate the confirmatory diagnosis of PCD. So far more than 40 genes have been associated with PCD, but most research have focused on common genes, which hinders our understanding of other rare PCD-genes. This review has summarized the PCD-associated genes and the corresponding characteristics of dysfunctional cilia, with an aim to provide a basis for early identification of such diseases.
Objective
To construct convenient CRISPR/Cas9-mediated genome editing systems in industrial enzyme-producing fungi
Penicillium oxalicum
and
Trichoderma reesei
.
Results
Employing the 5S rRNA promoter ...from
Aspergillus niger
for guide RNA expression, the β-glucosidase gene
bgl2
in
P. oxalicum
was deleted using a donor DNA carrying 40-bp homology arms or a donor containing no selectable marker gene. Using a markerless donor DNA as editing template, precise replacement of a small region was achieved in the
creA
gene. In
T. reesei
, the
A. niger
5S rRNA promoter was less efficient than that in
P. oxalicum
when used for gene editing. Using a native 5S rRNA promoter, stop codons were introduced into the
lae1
coding region using a markerless donor DNA with an editing efficiency of 36.67%.
Conclusions
Efficient genome editing systems were developed in filamentous fungi
P. oxalicum
and
T. reesei
by using heterologous or native 5S rRNA promoters for guide RNA expression.
Paramylon from Euglena gracilis (EGP) is a polymeric polysaccharide composed of linear β-1,3 glucan. EGP has been proved to have antibacterial activity, but its effect is weak due to its water ...insolubility and high crystallinity. In order to change this deficiency, this experiment carried out carboxymethylated modification of EGP. Three carboxymethylated derivatives, C-EGP1, C-EGP2, and C-EGP3, with a degree of substitution (DS) of 0.14, 0.55, and 0.78, respectively, were synthesized by varying reaction conditions, such as the mass of chloroacetic acid and temperature. Fourier transform infrared spectroscopy (FTIR), gel permeation chromatography (GPC), and nuclear magnetic resonance (NMR) analysis confirmed the success of the carboxymethylated modification. The Congo red (CR) experiment, scanning electron microscopy (SEM), X-ray diffraction (XRD), and thermogravimetry (TG) were used to study the conformation, surface morphology, crystalline nature, and thermostability of the carboxymethylated EGP. The results showed that carboxymethylation did not change the triple helix structure of the EGP, but that the fundamental particles’ surface morphology was destroyed, and the crystallization area and thermal stability decreased obviously. In addition, the water solubility test and antibacterial experiment showed that the water solubility and antibacterial activity of the EGP after carboxymethylation were obviously improved, and that the water solubility of C-EGP1, C-EGP2, and C-EGP3 increased by 53.31%, 75.52%, and 80.96% respectively. The antibacterial test indicated that C-EGP3 had the best effect on Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus), with minimum inhibitory concentration (MIC) values of 12.50 mg/mL and 6.25 mg/mL. The diameters of the inhibition zone of C-EGP3 on E. coli and S. aureus were 11.24 ± 0.15 mm and 12.05 ± 0.09 mm, and the antibacterial rate increased by 41.33% and 43.67%.
Artemis (
DCLRE1C
) is involved in opening recombination-activating gene (RAG1/RAG2)-generated hairpins during V(D)J recombination, an essential process for the differentiation and maturation of T ...and B cells. Here, we reported a case of 5-month-old boy with recurrent respiratory infections, disseminated Bacille Calmette-Guérin (BCG) infection, generalized erythroderma, hepatosplenomegaly, lymphadenopathy, eosinophillia and failure to thrive, symptoms often observed in Omenn syndrome. Genetic analysis revealed compound heterozygous mutations of the
DCLRE1C
gene, including deletions of exons 1 and 2, and a c. 352G>T (p. G118X) nonsense mutation in exon 5. Flow cytometry analysis of the patient PBMCs indicated a T
low
B
-
NK
+
immunophenotype. Short tandem repeat (STR) analysis confirmed transplacental maternal lymphocytes engraftment in circulating blood of the patient. Collectively, we reported a patient showing atypical immunophenotypic and typical clinical presentations of Severe Combined Immunodeficiency (SCID) with Graft Versus Host Disease (GVHD) in the context of compound heterozygous mutations of the
DCLRE1C
gene. This study adds to the ever-growing knowledge on the broad immunological and clinical spectrum associated with
DCLRE1C
mutations.
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