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Objective To investigate the effect of neurophysiological monitoring in extended endoscopic transsphenoidal surgery for cavernous sinus and clivus tumors. Methods We monitored the oculomotor nerve, trochlear nerve, trigeminal nerve and abducent nerve in 18 patients with cavernous sinus and clivus tumors by recording the free⁃electromyography (f⁃EMG) and triggered⁃electromyography (t⁃EMG) from August 2019 to December 2020. Two needle electrodes were inserted percutaneous into the levator palpebrae superioris muscle, superior oblique muscle, extraocular rectus muscle and masticatory muscle. To evaluate spontaneous muscle activity and complex muscle action potentials after cranial nerve stimulation. We evaluated the safety of cranial nerves and provided objective information for neurosurgeon. Results All the 18 patients with cavernous sinus and clivus tumors were treated by extended endoscopic transsphenoidal surgery, including 10 pituitary adenomas, 5 chordomas, 2 craniopharyngiomas and one cystic schwannoma. Total resection rate achieved 9/18, subtotal resection rate was 4/18, and partial resection rate was 5/18. There was no postoperative internal carotid artery (ICA) injury and cerebrospinal fluid leakage. A total of 20 oculomotor nerves, 3 trochlear nerves, 27 trigeminal nerves and 26 abducent nerves were recorded. There were one patient with left abducent nerve palsy and one patient with right abducent nerve paresis before surgery. The median follow⁃up time was 8.63 months, postoperative brain nerve injury occurred in 2 patients, the brain nerve injury rate was 2/18, all of which recovered 3 months after surgery. No patients with postoperative impaired trigeminal nerve function. Conclusions Monitoring of oculomotor nerve, trochlear nerve, trigeminal nerve and abducent nerve in extended endoscopic transsphenoidal surgery for cavernous sinus and clivus tumors is a safe and effective method. By monitoring and evaluating intraoperative f ⁃ EMG and t ⁃ EMG, neurosurgeons can adjust surgical procedures and strategies during tumor resection and reduce cranial nerve injuries.

Abstract Impending climate warming is expected to influence plant growth and distribution, and the distribution range limit of tree species is extremely sensitive to climate change. However, synchronous comparisons of responses of different tree species with overlapping ecological niches to climate at their distribution range limit in the same region have received little attention. In the present study, we assessed the discrepancy in radial growth responses of two dominant oak species to climate at their distribution range limit (southern range limit for Quercus mongolica, northern range limit for Quercus variabilis) in Beijing, China. Furthermore, growth–climate relationships were examined using linear mixed‐effects models, and growth trends up to the year 2100 were forecast based on future climate scenarios (RCP2.6 and RCP8.5). Our results indicated that there were no significant differences in the growth response to climate between Q. variabilis at its northern limit and Q. mongolica at its southern limit, and the growth of the two tree species was positively correlated with the minimum temperature and negatively correlated with the climatic moisture deficit of autumn. However, the growth response to climate variables varied at different sites. Additionally, the model forecast showed an increase in radial growth of Q. variabilis at its northern limit and Q. mongolica at its southern limit up to the end of the present century.

Misfire fault diagnosis is an important issue in on-board diagnosis (OBD) system, which has significant impacts on emissions, fuel consumption, and engine damage during vehicle movement. This study systematically reviews and summarizes the progress of misfire fault diagnosis methods, i.e., judgement basis, misfire diagnosis classification, and observer design. Finally, some perspectives on misfire fault diagnosis are also discussed. [ABSTRACT FROM AUTHOR]

Enterotoxigenic Escherichia coli (ETEC), a major global cause of diarrhea, initiates the pathogenic process via fimbriae-mediated attachment to the small intestinal epithelium. A common prototypic ETEC fimbria, colonization factor antigen I (CFA/I), consists of a tip-localized minor adhesive subunit CfaE and the stalk-forming major subunit CfaB, both of which are necessary for fimbrial assembly. To elucidate the structure of CFA/I at atomic resolution, three recombinant proteins were generated consisting of fusions of the minor and major subunits (CfaEB) and of two (CfaBB) and three (CfaBBB) repeats of the major subunit. Crystals of CfaEB diffracted X-rays to 2.1 Å resolution and displayed the symmetry of space group P21. CfaBB exhibited a crystal diffraction limit of 2.3 Å resolution and had the symmetry of space group P21212. CfaBBB crystallized in the monoclinic space group C2 and diffracted X-rays to 2.3 Å resolution. These structures were determined using the molecular-replacement method. [ABSTRACT FROM AUTHOR]

Three NAD kinase homologs, encoded by UTR1, POS5 and YEF1 genes, are found in the yeast Saccharomyces cerevisiae and proven to be important sources of NADPH for the cell. Pos5p, existing in the mitochondrial matrix, is critical for higher temperature endurance and mitochondrial functions, such as glycerol usability and arginine biosynthesis. Through constructing the high-copy expression plasmids of YEF1 and UTR1, which contained the green fluorescent protein reporter tag at their 3' terminus, and introducing them into POS5 gene deletion mutants (i.e. pos5, utr1pos5, yef1pos5 and utr1yef1pos5), the high-copy YEF1 and UTR1 plasmids carrying transformants for pos5 mutants were obtained. Their temperature sensitivity and growth phenotype on media with glycerol as the sole carbon source, or on media without arginine, were checked. Results showed the partial rescue of mitochondrial dysfunctions and temperature sensitivity of pos5 mutants by the high-copy YEF1 gene, and of glycerol growth defect and temperature sensitivity by the high-copy UTR1 gene, which confirmed the potential supplying ability of Yef1p and Utr1p for mitochondrial NADP(H) and implied the weak transport of NADP from cytosol to mitochondria. However, even through the green fluorescent protein reporter label, the subcellular localization of Yef1p and Utr1p in yeast cells could not be observed, which indicated the low expression level of these two NAD kinase homologs.

Enterotoxigenic Escherichia coli (ETEC) represents a formidable food and waterborne diarrheal disease threat of global importance. The first step in ETEC pathogenesis is bacterial attachment to small-intestine epithelial cells via adhesive fimbriae, many of which are genetically related to the prototype colonization factor antigen I (CFA/I). The minor fimbrial subunit CfaE is required for initiation of CFA/I fimbrial assembly and mediates bacterial attachment to host cell-surface receptors. A donor-strand complemented variant of CfaE (dscCfaE) was expressed with a hexahistidine tag, purified to homogeneity and crystallized using the hanging-drop vapor-diffusion method. X-ray diffraction data sets were collected to 2.4 A resolution for both native and derivatized crystals and showed the symmetry of space group P6(2)22, with unit-cell parameters a = b = 142.9, c = 231.9 A. Initial phases were derived from the SIRAS approach and electron density showed two molecules in the crystallographic asymmetric unit. Sequence assignments were aided by anomalous signals from the selenium of an SeMet-derivatized crystal and from S atoms of a native crystal.