Stem annual increments as ecobiological indicators in Turkey oak (Quercus cerris L.)

In recent decades, the biostatistical analysis of relationships among tree growth and macroclimatic factors has developed remarkably. In this discipline, the parametrisation of tree growth is generally based on the records of annual ring widths measured on breast height transverse sections of tree stems (ARI). The present research enables the stem volume annual increment (AVI) to be evaluated as a dendroclimatic indicator in comparison with ARI. The research is a part of a broader investigation into the ecobiological characteristics of Turkey oak in the Gargano region (southern Italy). The results indicate that AVI is no better than ARI as a means of highlighting expressive relationships among the examined macroclimatic factors (monthly precipitation and monthly averages of temperature daily maxima and minima) and the Turkey oak annual stem growth. In the examined stands, the most growthinfluencing factors are the autumn and spring rainfalls. Regarding the stem breast height radial increment, the most effective temperature factors are the June averages of daily minima and maxima.     

3D image-based dosimetry for Yttrium-90 radioembolization of hepatocellular carcinoma: Impact of imaging method on absorbed dose estimates

BackgroundTo improve therapy outcome of Yttrium-90 selective internal radiation therapy (⁹⁰Y SIRT), patient-specific post-therapeutic dosimetry is required. For this purpose, various dosimetric approaches based on different available imaging data have been reported. The aim of this work was to compare post-therapeutic 3D absorbed dose images using Technetium-99m (^99mTc) MAA SPECT/CT, Yttrium-90 (⁹⁰Y) bremsstrahlung (BRS) SPECT/CT, and ⁹⁰Y PET/CT.MethodsTen SIRTs of nine patients with unresectable hepatocellular carcinoma (HCC) were investigated. The ^99mTc SPECT/CT data, obtained from ^99mTc-MAA-based treatment simulation prior to ⁹⁰Y SIRT, were scaled with the administered ⁹⁰Y therapy activity. 3D absorbed dose images were generated by dose kernel convolution with scaled ^99mTc/⁹⁰Y SPECT/CT, ⁹⁰Y BRS SPECT/CT, and ⁹⁰Y PET/CT data of each patient. Absorbed dose estimates in tumor and healthy liver tissue obtained using the two SPECT/CT methods were compared against ⁹⁰Y PET/CT.ResultsThe percentage deviation of tumor absorbed dose estimates from ⁹⁰Y PET/CT values was on average −2 ± 18% for scaled ^99mTc/⁹⁰Y SPECT/CT, whereas estimates from ⁹⁰Y BRS SPECT/CT differed on average by −50 ± 13%. For healthy liver absorbed dose estimates, all three imaging methods revealed comparable values.ConclusionThe quantification capabilities of the imaging data influence ⁹⁰Y SIRT tumor dosimetry, while healthy liver absorbed dose values were comparable for all investigated imaging data. When no ⁹⁰Y PET/CT image data are available, the proposed scaled ^99mTc/⁹⁰Y SPECT/CT dosimetry method was found to be more appropriate for HCC tumor dosimetry than ⁹⁰Y BRS SPECT/CT based dosimetry.     

床旁超声联合颅内血流监测预测心肺复苏患者颅内压升高的效果研究

摘要 目的：探讨床旁超声联合颅内血流监测预测心肺复苏患者颅内压升高的效果。方法：选择2020年1月至2022年12月在本院重症医学科行心肺复苏治疗的60例患者作为研究对象，于心肺复苏术后采用脑室测压导管测定颅内压，根据颅内压结果将患者分为颅内高压组和正常组。采用酶联免疫吸附法检测两组患者血清脑源性神经营养因子（BDNF）、中枢神经特异性蛋白（S100β）和神经元特异性烯醇化酶（NSE）水平。比较两组患者视神经鞘宽度（ONSD）、大脑中动脉搏动指数（MCA-PI）。采用Pearson分析颅内压、ONSD与MCA-PI之间的相关性。绘制受试者工作特征（ROC）曲线分析患者ONSD、MCA-PI对的心肺复苏术后颅内压升高的预测价值。结果：（1）60例心肺复苏患者中19例出现颅内压升高；（2）颅内高压组患者血清BDNF、S100β和NSE水平均显著高于正常组（P<0.05）；（3）颅内高压组患者ONSD和MCA-PI均显著高于正常组（P<0.05）；（4）心肺复苏患者ICP与ONSD、MCA-PI均呈显著正相关关系（r=0.872、0.848，P<0.05）。（5）ONSD和MCA-PI预测心肺复苏患者发生颅内压升高的AUC分别为0.875（95%CI：0.739~1.000）、0.841（95%CI：0.735~0.948）。ONSD预测心肺复苏患者颅内压升高的最佳截断值为≥5.69 mm，对应敏感度、特异度、约登指数、阳性预测值和阴性预测值分别为78.95%、100.00%、78.95%、100.00%和91.11%；MCA-PI预测心肺复苏患者颅内压升高的最佳截断值为≥0.945，对应敏感度、特异度、约登指数、阳性预测值和阴性预测值分别为78.95%、80.49%、59.44%、65.22%和89.19%。结论：床旁超声和颅内血流监测均无创安全，ONSD和MCA-PI都可以有效预测心内复苏患者颅内压升高，ONSD预测效能更佳。     

Intérêt de la TEP/TDM au 18F-FDG dans la neurofibromatose de type 1, expérience du centre national de référence Henri-Mondor sur 10 ans

ObjectiveMalignant peripherals nerve sheath tumours (MPNST) are one of the leading causes of death in neurofibromatosis type 1 (NF1). Given the temporal and spatial multiplicity of suspicious lesions, the histological diagnosis of certainty might require iterative and decaying surgical procedure. Our objective was to determine the threshold values of metabolic metrics determined on ¹⁸F-FDG PET/CT (SUV_max, total lesion glycolysis [TLG], total metabolic tumour volume [TMTV], tumour-to-liver [T/L] ratio and heterogeneity index [HI]) in order to distinguish at best MPNST from benign lesion (simple neurofibromas [NF] or dysplastic NF).Patients and methodsHundred and seven patients from the national reference centre of NF1 Henri-Mondor, clinically suspects of TMGN, underwent 160 ¹⁸F-FDG PET/CT over a period of 10 years, between 2005 and 2015. The hypermetabolics lesions identified on ¹⁸F-FDG PET/CT were confronted with pathological analysis or clinico-radiological and metabolic follow-up of more than 6 months.ResultsFour hundred and eight hypermetabolics lesions were identified, of which 112 were histologically confronted with 38 simple NF, 29 dysplastic NF, 39 TMGN and 6 incidentalomas. The remaining 296 hypermetabolics lesions experienced a median follow-up of 40.4 months [13.5–137 months]. The optimal cut-off values for malignant lesions, determined by ROC curves, were in order of decreasing performance: T/L ratio > 2.03 (sensitivity 96%, specificity 88%); SUVmax > 4.74 (sensitivity 93%, specificity 86%); TLG > 172 (sensitivity 84%, specificity 76%); TMTV > 53.5 (sensitivity 83%, specificity 68%); HI > 1.63 (sensitivity 84%, specificity 54%).Conclusions¹⁸F-FDG PET/CT is a powerful diagnostic and prognostic tool in the management of TMGN. Metabolic metrics allow with good sensitivity and specificity to identify lesions transformed into TMGN. The advent of PET/MRI will undoubtedly allow in the near future to reinforce the diagnostic and prognostic performances for the detection of transformations of neurofibromas in TMGN.     

老年患者脓毒性休克液体复苏速度与预后的关系

目的探讨老年患者脓毒性休克液体复苏过程中输液速度与预后的相关性。方法回顾性分析92例严重感染病人液体复苏效果。按液体复苏期间的输液速度分为慢速组（〈500ml/h）和快速组（≥500ml/h）,并对两组患者的心率、有创及无创血压、血氧饱和度、呼吸、中心静脉压（CVP）、每小时尿量、尿比重、血乳酸、ScVO2及有无发生肺水肿、急性心功能不全、急性肾功能不全、MODS和7天死亡率、28天死亡率及入住ICU时间、住院时间等指标进行分析比较。结果两组患者在液体复苏过程中CVP和MAP两项指标比较无统计学意义。慢速组的尿量达标时间耗时较长（P〈0.05）;ScVO2及乳酸清除率比较无明显差异。快速组对液体的需求量多,而应用血管活性药物的病例数则少于慢速组;发生肺水肿、急性心功能不全的比例高于慢速组（P〈0.05）。两组急性肾功能不全的发生率相近,但慢速组出现MODS的例数少（P〈0.05）。7天死亡率和28天死亡率比较,慢速组低于快速组,但无统计学意义。两组患者住院时间无显著统计学意义,入住ICU时间慢速组明显短于快速组（P〈0.05）。结论在脓毒性休克复苏过程中不可一味靠加快输液速度来保证组织灌注,尤其对于老年患者,更应控制单位时间内的输液量,避免给储备能力较差的心功能造成更大的负担。在保证主要脏器灌注的情况下可以适当应用血管活性药物。     

Inactivation of Salmonella Typhimurium and Listeria monocytogenes using high-pressure treatments: destruction or sublethal stress?

AIMS: To investigate potential resuscitation of Listeria monocytogenes and Salmonella Typhimurium after high hydrostatic pressure treatments. METHODS AND RESULTS: Pressure treatments were applied at room temperature for 10 min on bacterial suspensions in buffers at pH 7 and 5.6. Total bacterial inactivation (8 log(10) CFU ml(-1) of bacterial reduction) obtained by conventional plating was achieved regarding both micro-organisms. Treatments at 400 MPa in pH 5.6 and 600 MPa in pH 7 for L. monocytogenes and at 350 MPa in pH 5.6 and 400 MPa in pH 7 for S. Typhimurium were required respectively. A 'direct viable count' method detected some viable cells in the apparently totally inactivated population. Resuscitation was observed for the two micro-organisms during storage (at 4 and 20 degrees C) after almost all treatments. In the S. Typhimurium population, 600 MPa, 10 min, was considered as the treatment achieving total destruction because no resuscitation was observed under these storage conditions. CONCLUSIONS: We suggest a delay before performing counts in treated samples in order to avoid the under-evaluation of surviving cells. SIGNIFICANCE AND IMPACT OF THE STUDY: The resuscitation of pathogen bacteria after physical treatments like high hydrostatic pressure has to be considered from the food safety point of view. Further studies should be performed in food products to study this resuscitation phenomenon.     

The Corynebacterium glutamicum gene pmt encoding a glycosyltransferase related to eukaryotic protein-O-mannosyltransferases is essential for glycosylation of the resuscitation promoting factor (Rpf2) and other secreted proteins

Two-dimensional gel electrophoresis and immunoassays revealed several proteins of the secretory subproteome of Corynebacterium glutamicum to be glycosylated. By genome-wide searches for genes involved in glycosylation, the C. glutamicum gene cg1014 was found to exhibit significant similarity to eukaryotic protein-O-mannosyltransferases (PMTs) and to a recently identified orthologue of Mycobacterium tuberculosis, Rv1002c, which is responsible for protein-O-mannosylation. The putative membrane protein Cg1014 showed the same predicted transmembrane topology as Saccharomyces cerevisiae PMT1 and M. tuberculosis Rv1002c along with conserved amino acid residues responsible for catalytic activity. Deletion of the C. glutamicum pmt gene (cg1014) caused a complete loss of glycosylation of secreted proteins including the resuscitation promoting factor 2 (Rpf2), which is involved in intercellular communication and growth stimulation of C. glutamicum. Because the gene pmt as well as rpf genes are present in the genomes of all actinobacteria sequenced so far, this work provides new insights into bacterial protein glycosylation and new opportunities to elucidate the molecular mechanisms of Rpf activity in pathogenic growth and infection.     

巢湖微囊藻产毒株的分离、保存及种属特异性鉴定

利用平板划线结合液体培养的方法从巢湖分离得到一个藻株,命名为Chaohu-1。甲醇粗提该藻株所产生的藻毒素(MCs),经固相萃取、HPLC检测,证实该藻株产生毒性最强的Microcystin-LR。藻细胞呈绿色球状,群体为无规则网状。全细胞PCR扩增藻蓝蛋白基因间隔序列(PC-IGS),结果与GenBank中已有的铜绿微囊藻属序列相似性达99%。综合形态学和分子生物学的分析结果,表明我们首次从巢湖分离得到1个产毒的铜绿微囊藻藻株。同时我们摸索出该藻株冻存及复苏方法,为藻株的长期保存及后续研究打下了基础。     

冷冻电镜密度图可视化软件VAT4M

基于冷冻电镜三维密度图的特征分析,研究开发了冷冻电镜密度图可视化软件VAT4M(Visual Analysis Tools for Macro-Molecule Map and Model),实现了对三维冷冻电镜密度图的可视化分析,其主要功能包括密度图和分子模型的可视化、密度图的分割和晶体结构在密度图中的匹配。在可视化方面,在实现等值面可视化方法的同时还实现了体绘制可视化模式。对于结构分析,VAT4M提供了自动分割工具,和所见即所得的分割浏览器。同时,VAT4M还提供了极值吸收法与梯度法相结合的自动匹配方法,而且,对于具有对称性的密度图,可根据一个亚基的匹配结果,迅速得到其准原子模型。最后给出了若干应用实例。实验表明,本平台对冷冻电镜密度数据具有良好的可视与分析功能。     

Towards native-state imaging in biological context in the electron microscope

Modern cell biology is reliant on light and fluorescence microscopy for analysis of cells, tissues and protein localisation. However, these powerful techniques are ultimately limited in resolution by the wavelength of light. Electron microscopes offer much greater resolution due to the shorter effective wavelength of electrons, allowing direct imaging of sub-cellular architecture. The harsh environment of the electron microscope chamber and the properties of the electron beam have led to complex chemical and mechanical preparation techniques, which distance biological samples from their native state and complicate data interpretation. Here we describe recent advances in sample preparation and instrumentation, which push the boundaries of high-resolution imaging. Cryopreparation, cryoelectron microscopy and environmental scanning electron microscopy strive to image samples in near native state. Advances in correlative microscopy and markers enable high-resolution localisation of proteins. Innovation in microscope design has pushed the boundaries of resolution to atomic scale, whilst automatic acquisition of high-resolution electron microscopy data through large volumes is finally able to place ultrastructure in biological context.