乳杆菌抑制幽门螺杆菌感染的分子机制

乳杆菌具有调节胃肠道菌群、改善胃肠道功能的益生作用。幽门螺杆菌是定植于胃黏膜的革兰阴性致病菌,可诱发胃癌。目前,幽门螺杆菌根除率逐年下降,临床上开始尝试应用嗜酸乳杆菌、鼠李糖乳杆菌和加氏乳杆菌等乳杆菌联合抗生素治疗幽门螺杆菌。然而不同临床研究结论有差异,临床疗效仍有待提升。该文通过综述乳杆菌治疗幽门螺杆菌的临床研究,进一步探讨其抑制幽门螺杆菌感染的分子机制,包括细菌素的直接杀菌、黏附抑制、胃肠道微生物群调节、炎症抑制等,为筛选理想乳杆菌菌株,提高幽门螺杆菌临床疗效提供新方案。

山西省大同市早播饲用燕麦叶部真菌病害病原鉴定及影响因素分析

山西省大同市是我国饲用燕麦的主产区之一,叶部真菌病害已成为限制其生产的主要因素,但目前尚不清楚病害种类及病原。此外,早播燕麦罹患病害产生的侵染源可能增加复种植物病害流行风险,阻碍燕麦可持续生产,迫切需要明确影响早播燕麦病害发生程度的主要因素,有针对性地制定防治措施。鉴于此,利用形态学特征和致病性测定对大同市天镇县的早播饲用燕麦种植田发现的叶部真菌病害进行鉴定,并且分析了收获期病情指数和病害影响因素之间的关系。结果表明:早播饲用燕麦共发现3种由真菌引致的叶部病害,分别为禾谷炭疽菌(Colletotrichum cereale)引致的叶枯病,燕麦内脐孺孢(Drechslera avenacea)引致的条斑病和禾柄锈菌燕麦转化型(Puccinia graminis f.sp.avenae)引致的秆锈病。不同种植和管理方式下,饲用燕麦叶枯病、条斑病和秆锈病均有不同程度发生,病情指数均值分别在1.9~5.6,1.0~6.2和0~0.9。相关性分析表明:喷灌是导致条斑病发病严重的主要因素,豆禾混播能降低饲用燕麦叶枯病的发生程度。此外,土壤速效N和速效K含量也能影响叶枯病和秆锈病的发生。建议牧草种植者在生产饲用燕麦时,采用合理的灌溉和施肥模式,推广牧草混播等种植技术,使用低毒高效杀菌剂对早播饲用燕麦进行病害防治,保证饲用燕麦产业的可持续发展。

ANiN(A=Li,Na,Mg,Ca)的结构、热力学、弹性和电子性质的第一性原理研究

三元过渡金属氮化物ANiN(A=Li,Na,Mg,Ca)是潜在的可充放电池的电极材料。物理性质,比如热稳定性、电子能隙以及弹性稳定性等,对于这些材料的电池应用都是非常重要的。本文使用第一原理方法,对比研究了ANiN这些材料的结构、动力学、弹性和电子结构性质。对状态方程和声子谱的计算被用来确定体系的稳定结构。对最稳定结构的弹性常数的计算表明,这些稳定结构都满足Born-Huang的稳定性判据,意味着它们的弹性稳定性。对体系电子结构的计算表明,LiNiN和CaNiN是半金属(half-metals),MgNiN是磁性材料,而NaNiN是通常的金属。这些材料的磁学性质都通过Stoner理论进行了解释。最后,电荷密度的计算被用来很好地说明了这些材料中的Ni-N成键的特征,表明成键特点主要是离子性的,但明显地混合了共价性。

Expert Consensus on Pathological Diagnosis of Intrahepatic Cholangiocarcinoma(2022 version)

Intrahepatic cholangiocarcinoma(iCCA)can originate from the large bile duct group(segment bile ducts and area bile ducts),small bile duct group(septal bile ducts and interlobular bile ducts),and terminal bile duct group(bile ductules and canals of Hering)of the intrahepatic biliary tree,which can be histopathological corresponding to large duct type iCCA,small duct type iCCA and iCCA with ductal plate malformation pattern,and cholangiolocarcinoma,respectively.The challenge in pathological diagnosis of above subtypes of iCCA falls in the distinction of cellular morphologies,tissue structures,growth patterns,invasive behaviors,immunophenotypes,molecular mutations,and surgical prognoses.For these reasons,this expert consensus provides nine recommendations as a reference for standardizing and refining the diagnosis of pathological subtypes of iCCA,mainly based on the 5th edition of the World Health Organization Classification of Tumours of the Digestive System.

Changes in bone mineral density among women aged 19-24 years using injectable contraceptive depot medroxyprogesterone acetate

Objective To compare bone mineral density （BMD） between users of intramuscular depot medroxyprogesterone acetate （DMPA） and nonhormonal control subjects. Methods The study included 87 women aged between 19 and 24 years using DMPA （DMPA group）for 24 months and 83 same-age women using nonhormonal contraception as control group. BMD of the lumbar spine and femoral neck were measured using dual-energy X-ray absorptiometry, comparing mean BMD changes in DMPA group with the control. Results After 24 months of DMPA treatment, as compared ~ith baseline, the mean BMD in lumbar spine and femoral neck were decreased by 2.67% and 2.71%, respectively. The mean lumbar spine and femoral neck BMD in DMPA group at 24 months were not significantly different compared with baseline （P=0. 080 and P=0. 076, respectively）. In comparison, in control group, there was a trend toward increasing BMD. After 24 months of observation, the mean percentage changes from baseline in lumbar spine and femoral neck BMD were increased by 1.24% and 1.30%, respectively. There was no significantly difference compared with baseline （P=0. 436 and P=0.373, respectively）. Mean BMD at the spine and femoral neck did not differ significantly between DMPA users and nonusers over 12 months （P=0.153 and P=0.140, respectively）, but the BMD at both anatomical sites was significantly lower in DMPA group than in the control after 24 months of treatment （P=0.012 and P=0.008, respectively）. Conclusion The use of DMPA for short-term （≤12-month） had no significant effects on BMD at spine and femoral neck, but long-term exposure to DMPA had significant loss in BMD in women aged between 19 and 24 years.

Effect of depot medroxyprogesterone acetate(DMPA) on bone mineral density(BMD) and evaluating changes in BMD after discontinuation of DMPA in adolescent women

Objective To compare bone mineral density （BMD） between users of intramuscular depot medroxyprogesterone acetate （DMPA） and nonhormonal subjects and evaluated the changes in BMD after discontinuation of DMPA.Methods The study included 102 women aged 16-18 years using DMPA for 24 months and 97 same-age nonusers. BMD of the lumbar spine and femoral neck were measured using dual-energy X-ray absorptiometry. The mean BMD values were compared between DMPA users （DMPA group） and nonusers （control group） and the changes of BMD during 36 months after discontinuation of DMPA were observed.Results Mean BMD at the spine and femoral neck did not differ significantly between DMPA group and control group over 12 months, but the BMD values at both anatomical sites were significantly lower in DMPA group than in control group after 24 months treatment. After DMPA discontinuation, the mean BMD values in DMPA users increased substantially. At 24 months after DMPA discontinuation, there were no significant differences between DMPA group and control group. But the values of the lumbar spine and femoral neck BMD in DMPA group were still 1.70% and 1.87%, respectively, below nonusers at 36 months after DMPA discontinuation.Conclusion The use of DMPA for short-term （ ≤12 months） had no significant effects on BMD at spine and femoral neck, but long-term exposure to DMPA had significant loss in BMD in adolescents. Bone loss occurring with DMPA use is reversible after DMPA discontinuation.

Study on Integral Dissolution Model Based on Biological Potency for Compound Chinese Materia Medica

Objective To investigate the integral dissolution model based on biological potency in order to evaluate the dissolution of Compound Chinese materia medica（CCMM） in vitro. Methods The contents of paeoniflorin, phillyrin, ginsenoside Rg1, and adenosine of ten batches of Compound Biejia Ruangan Tablet（CBRT） were determined at different times. The self-defined weighting coefficient based on the contents has been created to establish the integral dissolution model. In addition, the biological potency of CBRT was measured by MTT assay. Then, the f2 similar factor was used to evaluate the similarity of the batches. Results Compared with batch a, some batches’ f2 values of paeoniflorin and adenosine were less than 50, while f2 values of ginsenoside Rg1, phillyrin, and integral component were more than 50. Likewise, ginsenoside Rg1, phillyrin, and integral component were all in good correlation with biological dissolution. Conclusion The results of the integral dissolution based on biological test of CBRT demonstrate that the bioassay method may be a promising supplement for its quality evaluation.