BpWOX11 promotes adventitious root formation in Betula pendula.

Adventitious root formation is a key step in vegetative propagation via cuttings. It is crucial for establishing birch plantations and preserve birch varieties. Although previous studies have highlighted role of WOX11 in controlling adventitious root formation, no such study has been conducted in birch. Understanding the mechanism of adventitious root formation is essential for improvement of rooting or survival rate using stem cuttings in birch. In this study, we cloned BpWOX11 and produced BpWOX11 overexpression (OE) transgenic lines using the Agrobacterium-mediated plant transformation. OE lines exhibited early initiated adventitious root formation, leading to increase the rooting rate of stem cuttings plants. RNA sequencing analysis revealed that OE lines induced the gene expression related to expansin and cell division pathway, as well as defense and stress response genes. These may be important factors for the BpWOX11 gene to promote adventitious root formation in birch cuttings. The results of this study will help to further understand the molecular mechanisms controlling the formation of adventitious roots in birch.

Effects of irradiation on the aging and sensory quality of navel orange distilled spirits.

BACKGROUND: 60 Co-γ irradiation can simulate the effects of aging and enhance the flavor of distilled spirits. The present study aimed to investigate the effects of 0, 2, 4, 6, 8 and 10 kGy 60 Co-γ irradiation doses on the key aroma components in newly produced navel orange distilled spirits and thus determine the mechanism of their aging distilled spirits. RESULTS: The identification of aroma compounds demonstrated that ethyl hexanoate, d-limonene, ethyl octanoate, 3-methyl-1-butanol and linalool are the key aroma compounds in navel orange distilled spirits, which were increased except for linalool with irradiation doses of 2-6 kGy. Irradiation treatment simulated the effects of the aging of navel orange distilled spirits by promoting the content of total acids, total esters and aldehydes. Irradiation doses of 2-6 kGy increased the aroma intensity of navel orange distilled spirits, reaching an optimum at 6 kGy. However, irradiation doses as high as 8 and 10 kGy decreased the content of esters in navel orange distilled spirits, which led to a deterioration of the spirit flavor. CONCLUSION: Low doses of 60 Co-γ irradiation can simulate the effects of the aging by increasing the content of key aromatic compounds in navel orange distilled spirits. © 2023 Society of Chemical Industry.

Distribution characteristics of pathogenic bacteria in hospitalized HIV/AIDS patients with wound infection in Yunnan / 中国热带医学

@#Abstract: Objective　To analyze the distribution characteristics of the main pathogens of HIV/AIDS patients with wound infections and provide basis for clinical diagnosis and treatment. Methods　The clinical data of 294 patients with positive secretions or pus specimens from 2016 to 2020 were analyzed retrospectively. Results　A total of 357 strains of pathogenic bacteria were isolated from 294 cases, of which 123 strains of Gram-negative bacilli (G-b), accounting for 34.5%, were mainly Escherichia coli (15.4%), Klebsiella pneumoniae (3.9%), and Pseudomonas aeruginosa (3.6%); Gram-positive bacilli (G+b) 14 strains, accounting for 3.9%; 108 Gram-positive cocci (G+c), accounting for 30.3%, of which 44 strains were coagulase-positive Staphylococcus aureus (12.3%), Coagulase-negative staphylococci were mainly Staphylococcus epidermidis (4.2%) and Staphylococcus hemolyticus (2.8%); 37 strains of fungi, accounting for 10.4%, were mainly Candida albicans (5.9%); 75 strains of Mycobacterium, accounting for 21.0%, including 41 strains of Mycobacterium tuberculosis (11.5%) and 34 strains of non-tuberculosis mycobacteria (9.5%). 52 of the 294 HIV/AIDS patients had mixed infections, accounting for 17.7%. There was significant difference in the distribution of G+c, G-b, mycobacteria and mixed infection among different specimen sources (P<0.05), and there was significant difference in the distribution of mycobacteria among different CD4+T lymphocyte counts (P<0.05). There was significant difference in the level of CD4+T lymphocytes between patients of different ages (P<0.05), and there was significant difference in the level of CD4+T lymphocytes from postoperative incision and other parts (P<0.05). Conclusions　Patients with HIV/AIDS are prone to combined wound infections with various pathogenic bacteria. We should strengthen the research on wound infection in HIV/AIDS patients, and timely send patients with a low number of CD4+T lymphocytes for secretion or pus culture, so as to carry out targeted treatment and improve the prognosis of patients.

Chemical and structural changes associated with Cu-catalyzed alkaline-oxidative delignification of hybrid poplar.

BACKGROUND: Alkaline hydrogen peroxide pretreatment catalyzed by Cu(II) 2,2'-bipyridine complexes has previously been determined to substantially improve the enzymatic hydrolysis of woody plants including hybrid poplar as a consequence of moderate delignification. In the present work, cell wall morphological and lignin structural changes were characterized for this pretreatment approach to gain insights into pretreatment outcomes and, specifically, to identify the extent and nature of lignin modification. RESULTS: Through TEM imaging, this catalytic oxidation process was shown to disrupt cell wall layers in hybrid poplar. Cu-containing nanoparticles, primarily in the Cu(I) oxidation state, co-localized with the disrupted regions, providing indirect evidence of catalytic activity whereby soluble Cu(II) complexes are reduced and precipitated during pretreatment. The concentration of alkali-soluble polymeric and oligomeric lignin was substantially higher for the Cu-catalyzed oxidative pretreatment. This alkali-soluble lignin content increased with time during the catalytic oxidation process, although the molecular weight distributions were unaltered. Yields of aromatic monomers (including phenolic acids and aldehydes) were found to be less than 0.2 % (wt/wt) on lignin. Oxidation of the benzylic alcohol in the lignin side-chain was evident in NMR spectra of the solubilized lignin, whereas minimal changes were observed for the pretreatment-insoluble lignin. CONCLUSIONS: These results provide indirect evidence for catalytic activity within the cell wall. The low yields of lignin-derived aromatic monomers, together with the detailed characterization of the pretreatment-soluble and pretreatment-insoluble lignins, indicate that the majority of both lignin pools remained relatively unmodified. As such, the lignins resulting from this process retain features closely resembling native lignins and may, therefore, be amenable to subsequent valorization.

Rapid and effective oxidative pretreatment of woody biomass at mild reaction conditions and low oxidant loadings.

BACKGROUND: One route for producing cellulosic biofuels is by the fermentation of lignocellulose-derived sugars generated from a pretreatment that can be effectively coupled with an enzymatic hydrolysis of the plant cell wall. While woody biomass exhibits a number of positive agronomic and logistical attributes, these feedstocks are significantly more recalcitrant to chemical pretreatments than herbaceous feedstocks, requiring higher chemical and energy inputs to achieve high sugar yields from enzymatic hydrolysis. We previously discovered that alkaline hydrogen peroxide (AHP) pretreatment catalyzed by copper(II) 2,2΄-bipyridine complexes significantly improves subsequent enzymatic glucose and xylose release from hybrid poplar heartwood and sapwood relative to uncatalyzed AHP pretreatment at modest reaction conditions (room temperature and atmospheric pressure). In the present work, the reaction conditions for this catalyzed AHP pretreatment were investigated in more detail with the aim of better characterizing the relationship between pretreatment conditions and subsequent enzymatic sugar release. RESULTS: We found that for a wide range of pretreatment conditions, the catalyzed pretreatment resulted in significantly higher glucose and xylose enzymatic hydrolysis yields (as high as 80% for both glucose and xylose) relative to uncatalyzed pretreatment (up to 40% for glucose and 50% for xylose). We identified that the extent of improvement in glucan and xylan yield using this catalyzed pretreatment approach was a function of pretreatment conditions that included H2O2 loading on biomass, catalyst concentration, solids concentration, and pretreatment duration. Based on these results, several important improvements in pretreatment and hydrolysis conditions were identified that may have a positive economic impact for a process employing a catalyzed oxidative pretreatment. These improvements include identifying that: (1) substantially lower H2O2 loadings can be used that may result in up to a 50-65% decrease in H2O2 application (from 100 mg H2O2/g biomass to 35-50 mg/g) with only minor losses in glucose and xylose yield, (2) a 60% decrease in the catalyst concentration from 5.0 mM to 2.0 mM (corresponding to a catalyst loading of 25 µmol/g biomass to 10 µmol/g biomass) can be achieved without a subsequent loss in glucose yield, (3) an order of magnitude improvement in the time required for pretreatment (minutes versus hours or days) can be realized using the catalyzed pretreatment approach, and (4) enzyme dosage can be reduced to less than 30 mg protein/g glucan and potentially further with only minor losses in glucose and xylose yields. In addition, we established that the reaction rate is improved in both catalyzed and uncatalyzed AHP pretreatment by increased solids concentrations. CONCLUSIONS: This work explored the relationship between reaction conditions impacting a catalyzed oxidative pretreatment of woody biomass and identified that significant decreases in the H2O2, catalyst, and enzyme loading on the biomass as well as decreases in the pretreatment time could be realized with only minor losses in the subsequent sugar released enzymatically. Together these changes would have positive implications for the economics of a process based on this pretreatment approach.

Catalysis with Cu(II) (bpy) improves alkaline hydrogen peroxide pretreatment.

Copper(II) 2,2'-bipyridine (Cu(II) (bpy))-catalyzed alkaline hydrogen peroxide (AHP) pretreatment was performed on three biomass feedstocks including alkali pre-extracted switchgrass, silver birch, and a hybrid poplar cultivar. This catalytic approach was found to improve the subsequent enzymatic hydrolysis of plant cell wall polysaccharides to monosaccharides for all biomass types at alkaline pH relative to uncatalyzed pretreatment. The hybrid poplar exhibited the most significant improvement in enzymatic hydrolysis with monomeric sugar release and conversions more than doubling from 30% to 61% glucan conversion, while lignin solubilization was increased from 36.6% to 50.2% and hemicellulose solubilization was increased from 14.9% to 32.7%. It was found that Cu(II) (bpy)-catalyzed AHP pretreatment of cellulose resulted in significantly more depolymerization than uncatalyzed AHP pretreatment (78.4% vs. 49.4% decrease in estimated degree of polymerization) and that carboxyl content the cellulose was significantly increased as well (fivefold increase vs. twofold increase). Together, these results indicate that Cu(II) (bpy)-catalyzed AHP pretreatment represents a promising route to biomass deconstruction for bioenergy applications.

Esmolol protects the myocardium and facilitates direct version intracardiac operation with a beating heart.

In recent years there has been renewed interest in beating heart surgery using the ultra-active and selective beta1-blocker, esmolol. However, there has not been a report of its use in direct version intracardiac surgery with beating heart. Twenty-four patients undergoing elective direct version intracardiac surgery (mitral valve replacement) were divided randomly into 2 groups: control group (normothermia cardiopulmonary bypass (CPB) direct version intracardiac beating heart surgery) and esmolol group (normothermia CPB direct version intracardiac beating heart surgery and intravenous esmolol drip during CPB to maintain heart rate at 30-50 beats/min). Steady hemodynamic parameters were maintained in both groups; however, the doses of dopamine used in control group were larger than those for the esmolol group (p<0.01). The myocardial ultrastructure was well maintained in both group, but the scores for myocardial mitochondria, glycogen grading and counting and the amount of adenosine triphosphate were higher in the esmolol group (p<0.05). There was no significant change in the malondialdehyde level in either group (p>0.05). Using esmolol in direct version intracardiac beating heart surgery protects the myocardium and facilitates the operation.