The xylitol dehydrogenase(XDH)is a crucial enzyme involved in the xylose utilization in pentose-catabolizing yeasts and fungi.In addition to producing xylulose,XDH can also be employed to develop a biosensor for monitoring xylitol concentration.In this study,the gene encoding the thermophilic fungus Talaromyces emersonii XDH(TeXDH)was heterologously expressed in Escherichia coli BL21(DE3)at 16 ℃ in the soluble form.Recombinant TeXDH with high purity was purified by using a Ni-NTA affinity column.Size-exclusion chromatography and SDS-PAGE analysis demonstrated that the puri-fied recombinant TeXDH exists as a native trimer with a molecular mass of approximately 116 kD,and is composed of three identical subunits,each with a molecular weight of around 39 kD.The TeXDH strictly preferred NAD+as a coenzyme to NADP+.The optimal temperature and pH of the TeXDH were 40 ℃and 10.0,respectively.After EDTA treatment,the enzyme activity of TeXDH decreased to 43.26％of the initial enzyme activity,while the divalent metal ions Mg2+or Ca2+could recover the enzyme activity of TeXDH,reaching 103.32％and 110.69％of the initial enzyme activity,respectively,making them the optimal divalent metal ion cofactors for TeXDH enzyme.However,the divalent metal ions of Mn2+,Ni2+,Cu2+,Zn2+,Co2+,and Cd2+significantly inhibited the activity of TeXDH.ICP-MS and molecular doc-king studies revealed that 1 mol/L of TeXDH bound 2 mol/L Zn2+ions and 1 mol/L Mg2+ion.Further-more,TeXDH exhibited a high specificity for xylitol,laying the foundation for the development of future xylitol biosensors.

The interactions between microorganisms and medicinal plants are crucial to the quality improvement of medicinal plants. Medicinal plants attract microorganisms to colonize by secreting specific compounds and provide niche and nutrient support for these microorganisms, with a symbiotic network formed. These microorganisms grow in the rhizosphere, phyllosphere, and endophytic tissues of plants and significantly improve the growth performance and medicinal component accumulation of medicinal plants by promoting nutrient uptake, enhancing disease resistance, and regulating the synthesis of secondary metabolites. Microorganisms are also widely used in the ecological planting of medicinal plants, and the growth conditions of medicinal plants are optimized by simulating the microbial effects in the natural environment. The interactions between microorganisms and medicinal plants not only significantly improve the yield and quality of medicinal plants but also enhance their geoherbalism, which is in line with the concept of green agriculture and eco-friendly development. This study reviewed the research results on the interactions between medicinal plants and microorganisms in recent years and focused on the analysis of the great potential of microorganisms in optimizing the growth environment of medicinal plants, regulating the accumulation of secondary metabolites, inducing systemic resistance, and promoting the ecological planting of medicinal plants. It provides a scientific basis for the research on the interactions between medicinal plants and microorganisms, the research and development of microbial agents, and the application of microorganisms in the ecological planting of medicinal plants and is of great significance for the quality improvement of medicinal plants and the green and sustainable development of TCM resources.
Plants, Medicinal/metabolism* ; Bacteria/genetics* ; Symbiosis

Nonobstructive azoospermia (NOA), one of the most severe types of male infertility, etiology often remains unclear in most cases. Therefore, this study aimed to detect four biallelic detrimental variants (0.5%) in the minichromosome maintenance domain containing 2 ( MCMDC2 ) genes in 768 NOA patients by whole-exome sequencing (WES). Hematoxylin and eosin (H&E) demonstrated that MCMDC2 deleterious variants caused meiotic arrest in three patients (c.1360G>T, c.1956G>T, and c.685C>T) and hypospermatogenesis in one patient (c.94G>T), as further confirmed through immunofluorescence (IF) staining. The single-cell RNA sequencing data indicated that MCMDC2 was substantially expressed during spermatogenesis. The variants were confirmed as deleterious and responsible for patient infertility through bioinformatics and in vitro experimental analyses. The results revealed four MCMDC2 variants related to NOA, which contributes to the current perception of the function of MCMDC2 in male fertility and presents new perspectives on the genetic etiology of NOA.
Humans ; Male ; Azoospermia/genetics* ; Meiosis/genetics* ; Spermatogenesis/genetics* ; Adult ; Exome Sequencing ; Microtubule-Associated Proteins/genetics* ; Alleles ; Infertility, Male/genetics*

Non-functioning pituitary adenomas(NFPAs)are relatively common.Apart from hyperprolactinemia caused by pituitary compression,they typically lack overt hormonal hypersecretion and usually present with clinical symptoms due to mass effects.Previously considered a uniform entity,NFPAs are actually a highly heterogeneous group of tumors,including aggressive subtypes like silent corticotroph adenomas(SCA)and null cell adenomas.The 2022 WHO new classification of pituitary tumors employs transcription factors[e.g.,pituitary-specific transcription factor 1(PIT-1),T-box transcription factor 19(TBX19,also known as TPIT),steroidogenic factor 1(SF-1)]for detailed categorization,allowing precise subclassification of NFPAs into multiple subtypes derived from distinct cell lineages,including silent gonadotroph adenomas,SCA,and plurihormonal PIT-1-positive adenomas.This helps identify highly invasive subtypes with high recurrence risk,guiding clinical diagnosis and treatment,prognostic assessment,and individualized management.The new classification also provides a theoretical basis for targeted therapies of NFPAs(e.g.,somatostatin analogs and temozolomide).This review comprehensively discusses the latest pathological classification of NFPAs and its clinical implications,aiming to enhance understanding of this disease and offer valuable insights for precise diagnosis,treatment,and prognostic assessment.

The xylitol dehydrogenase(XDH)is a crucial enzyme involved in the xylose utilization in pentose-catabolizing yeasts and fungi.In addition to producing xylulose,XDH can also be employed to develop a biosensor for monitoring xylitol concentration.In this study,the gene encoding the thermophilic fungus Talaromyces emersonii XDH(TeXDH)was heterologously expressed in Escherichia coli BL21(DE3)at 16 ℃ in the soluble form.Recombinant TeXDH with high purity was purified by using a Ni-NTA affinity column.Size-exclusion chromatography and SDS-PAGE analysis demonstrated that the puri-fied recombinant TeXDH exists as a native trimer with a molecular mass of approximately 116 kD,and is composed of three identical subunits,each with a molecular weight of around 39 kD.The TeXDH strictly preferred NAD+as a coenzyme to NADP+.The optimal temperature and pH of the TeXDH were 40 ℃and 10.0,respectively.After EDTA treatment,the enzyme activity of TeXDH decreased to 43.26％of the initial enzyme activity,while the divalent metal ions Mg2+or Ca2+could recover the enzyme activity of TeXDH,reaching 103.32％and 110.69％of the initial enzyme activity,respectively,making them the optimal divalent metal ion cofactors for TeXDH enzyme.However,the divalent metal ions of Mn2+,Ni2+,Cu2+,Zn2+,Co2+,and Cd2+significantly inhibited the activity of TeXDH.ICP-MS and molecular doc-king studies revealed that 1 mol/L of TeXDH bound 2 mol/L Zn2+ions and 1 mol/L Mg2+ion.Further-more,TeXDH exhibited a high specificity for xylitol,laying the foundation for the development of future xylitol biosensors.

Objective To investigate the molecular mechanism of action of isoglycoside-4'-O-apigenin(1 → 2)glucoside(licraside)intervention in alleviating cholestasis.Methods Farnesol X receptor(FXR)was silenced in human HepG2 cells using lentivirus,and bilirubin and α-isothiocyanate(ANIT)were used to induce HepG2 cells to construct a hypercholate-hyperbilirubin model.The effects of licraside on cell viability,biochemical indices contents and the expression level of FXR and its downstream related proteins in the model were investigated.HepG2 cells and FXR-silenced HepG2 cells were divided into normal,model and experimental groups.Bilirubin and probenecid were added to all groups except the normal group,and 80 μmol·L-1 licraside was added to the experimental group.After 24 h of culture,cell viability and the levels of total bile acids(TBA),bilirubin and other biochemical indices were examined in each group;the protein expression levels of FXR and bile salt efflux pump(BSEP)were examined in each group by Western blot assay.Results The cell viability in HepG2 cells normal group,HepG2 cells model group,HepG2 cells experimental group,siFXR-HepG2 cells normal group,siFXR-HepG2 cells model group and siFXR-HepG2 cells experimental group were(100.00±17.15)％,(39.41±2.91)％,(70.79±3.74)％,(81.41±5.12)％,(33.49±2.69)％and(44.08±4.82)％;the levels of TBA were(7.98±5.87),(46.18±10.93),(9.25±7.20),(11.18±3.36),(38.28±5.12)and(34.79±5.39)μmol·L-1;the levels of total bilirubin were(5.21±3.27),(40.29±24.88),(5.21±2.64),(12.00±4.64),(56.36±14.85)and(15.39±5.56)μmol·L-1;the relative expression levels of FXR protein were 1.00±0.10,0.81±0.07,1.11±0.09,0.10±0.02,0.12±0.02 and 0.10±0.04;the relative expression levels of BSEP protein were 1.00±0.17,0.81±0.02,0.88±0.03,0.70±0.09,0.49±0.07 and 0.60±0.10.The differences of the above indexes in the HepG2 cells experimental group compared with the model group were statistically significant(P＜0.001,P＜0.01);except for TBA,the differences of the above indexes in siFXR-HepG2 cells experimental group compared with the model group were statistically significant(P＜0.001,P＜0.01).Conclusion Licraside can effectively reduce the biochemical indices level of hypercholate-hyperbilirubin cell model.This effect is achieved by agonizing of FXR protein expression,increase the efflux of bile acid salt and then reduce the synthesis of bile acids,and eventually achieve the effect of alleviating the cholestasis.

The patient,a male newborn,was admitted to the hospital 2 hours after birth due to prematurity(gestational age 27+5 weeks)and respiratory distress occurring 2 hours postnatally.After admission,the infant developed fever and elevated C-reactive protein levels.On the fourth day after birth,metagenomic next-generation sequencing of cerebrospinal fluid indicated a positive result for Mycoplasma hominis(9 898 reads).On the eighth day,a retest of cerebrospinal fluid metagenomics confirmed Mycoplasma hominis(56 806 reads).The diagnosis of purulent meningitis caused by Mycoplasma hominis was established,and the antibiotic treatment was switched to moxifloxacin[5 mg/(kg·day)]administered intravenously for a total of 4 weeks.After treatment,the patient's cerebrospinal fluid tests returned to normal,and he was discharged as cured on the 76th day after birth.This article focuses on the diagnosis and treatment of neonatal Mycoplasma hominis purulent meningitis,introducing the multidisciplinary diagnosis and treatment of the condition in extremely preterm infants.[Chinese Journal of Contemporary Pediatrics,2024,26(4):432-436]

Objective To investigate the incidence rate,clinical characteristics,and prognosis of neonatal stroke in Shenzhen,China.Methods Led by Shenzhen Children's Hospital,the Shenzhen Neonatal Data Collaboration Network organized 21 institutions to collect 36 cases of neonatal stroke from January 2020 to December 2022.The incidence,clinical characteristics,treatment,and prognosis of neonatal stroke in Shenzhen were analyzed.Results The incidence rate of neonatal stroke in 21 hospitals from 2020 to 2022 was 1/15 137,1/6 060,and 1/7 704,respectively.Ischemic stroke accounted for 75％(27/36);boys accounted for 64％(23/36).Among the 36 neonates,31(86％)had disease onset within 3 days after birth,and 19(53％)had convulsion as the initial presentation.Cerebral MRI showed that 22 neonates(61％)had left cerebral infarction and 13(36％)had basal ganglia infarction.Magnetic resonance angiography was performed for 12 neonates,among whom 9(75％)had involvement of the middle cerebral artery.Electroencephalography was performed for 29 neonates,with sharp waves in 21 neonates(72％)and seizures in 10 neonates(34％).Symptomatic/supportive treatment varied across different hospitals.Neonatal Behavioral Neurological Assessment was performed for 12 neonates(33％,12/36),with a mean score of(32±4)points.The prognosis of 27 neonates was followed up to around 12 months of age,with 44％(12/27)of the neonates having a good prognosis.Conclusions Ischemic stroke is the main type of neonatal stroke,often with convulsions as the initial presentation,involvement of the middle cerebral artery,sharp waves on electroencephalography,and a relatively low neurodevelopment score.Symptomatic/supportive treatment is the main treatment method,and some neonates tend to have a poor prognosis.

This study aimed to provide data support for resource utilization of the stems and leaves of Astragalus membranaceus var. mongholicus(SLAM) by analyzing and evaluating the chemical constituents. The crude protein, crude fiber, and soluble saccharide of SLAM were analyzed by Kjeldahl method, filtration method, and UV-Vis spectrophotometry, respectively. The nucleosides, amino acids, flavonoids, and saponins of SLAM were analyzed by ultraperformance liquid chromatography-triple quadrupole mass spectrometry(UPLC-TQ-MS). Combined with principal component analysis(PCA), the quality difference of resource components of SLAM was comprehensively evaluated. The results showed that the average content of crude protein, crude fiber, total polysaccharide, and redu-cing sugar in SLAM was 5.11%, 30.33%, 11.03 mg·g~(-1), and 31.90 mg·g~(-1), respectively. Six nucleosides, 15 amino acids, 22 flavonoids, and one saponin were detected, with an average content of 1.49 mg·g~(-1), 6.00 mg·g~(-1), 1.86 mg·g~(-1), and 35.67 μg·g~(-1), respectively. The content of various types of chemical components in SLAM differed greatly in different harvesting periods and growing years. The results of PCA showed that the quality of SLAM produced in Ningxia was superior. The results can provide references for the utilization of SLAM.
Astragalus propinquus/chemistry* ; Gas Chromatography-Mass Spectrometry ; Flavonoids/analysis* ; Plant Leaves/chemistry* ; Amino Acids ; Saponins/analysis*

The spider neurotoxin hainantoxin-IV(HNTX-IV), which is isolated from the crude venom of the spider Selenocosia hainana, can specifically inhibit the tetrodotoxin-sensitive(TTX-S) sodium channel, and can selectively inhibit Voltage-gated sodium channel(VGSC) Na