Evolution-Based Discovery of Polyketide Acylated Valine from a Cytochalasin-Like Gene Cluster in Simplicillium lamelliciola HDN13430.

Utilizing a gene evolution-oriented approach for gene cluster mining, a cryptic cytochalasin-like gene cluster (sla) in Antarctic-derived Simplicillium lamelliciola HDN13430 was identified. Compared with the canonical cytochalasin biosynthetic gene clusters (BGCs), the sla gene cluster lacks the key α,ß-hydrolase gene. Heterologous expression of the sla gene cluster led to the discovery of a new compound, slamysin (1), characterized by an N-acylated amino acid structure and demonstrating weak anti-Bacillus cereus activity. These findings underscore the potential of genetic evolution in uncovering novel compounds and indicating specific adaptive evolution within specialized habitats.

Multidrug-resistant bacteria infection and nursing quality management application in the department of physical examination.

The main problem of clinical prevention and control of multi drug resistant bacteria infection is to strengthen the monitoring of pathogenic bacteria spectrum, this study research on the multi drug-resistant bacteria infection and nursing quality management application in the department of physical examination. The results of this study showed that the number of patients with multiple drug resistant infections showed an increasing trend. Therefore, once the patients with multiple drug-resistant bacteria infection are found, the prevention and control of the patients with multiple drug-resistant bacteria should be strictly followed, and the patient's medication care should be highly valued. Also, the nurses need to be classified based on the knowledge and skill characteristics of the nurses in the department of physical examination, and compare the nursing effect before and after classification and grouping. The physicians and individuals receiving physical examinations in the department of physical examination had a higher degree of satisfaction for nursing effect after classification compared with those before classification. Classification and grouping management helps improve the nursing quality and overall quality of the nurses in the department of physical examination.

[Simultaneous identification and detection of 16 anabolic steroid hormones in muscle using liquid chromatography oupled to quadrupole/linear ion trap mass spectrometry].

A comprehensive method for simultaneous identification and detection of 16 anabolic steroid hormones (ASs, including andorgens, gestagens and their esters) in muscle samples was developed with liquid chromatography coupled to quadrupole/linear ion trap mass spectrometry (LC-Q/Trap-MS). The ASs in muscle samples were extracted with acetonitrile under ultrasonic assistance. The extract was defatted by n-hexane with liquid-liquid partitioning and followed by clean-up with NH2 solid phase extraction (SPE) cartridge. The separation of analytes was carried out on a CAPCELL PAK C18 MG II column (150 mm x 2.0 mm, 5.0 microm) using mobile phases of 0.1% (v/v) formic acid in acetonitrile and 0.1% (v/v) formic acid-5 mmol/L ammonium formate aqueous solution with gradient elution. A scheduled multiple reaction monitoring (sMRM) in positive mode as survey scan and an enhanced product ion (EPI) scan as dependent scan in an information-dependent acquisition (IDA) experiment was adopted in mass spectrometry acquisition. On-line lab-built MS/MS library and internal standards were employed for the identification and quantification. As a result, the 16 ASs showed good linearity with all correlation coefficients (r) no less than 0. 999 0 within the linear ranges. The limits of quantification (LOQs, S/N > or = 10) for the 16 ASs were in the range of 0.029-0.36 microg/kg. At the three spiked levels (0.5, 2.0 and 20 microg/kg), the overall recoveries ranged from 89.9% to 118% with the relative standard deviations (RSDs) no more than 16.2% under within--laboratory reproducibility conditions. The proposed method can be used to identify and detect the 16 ASs in a single run, which makes it effective in residue surveillance of anabolic hormones in muscle samples.