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71.
72.
Thoracic ultrasound (TUS) is an easy-to-use imaging modality that aids physicians in the differential diagnosis of respiratory diseases. However, no data exist on the TUS findings of acute eosinophilic pneumonia (AEP) or their clinical utility in patients with AEP. Thus, we performed an observational study on TUS findings and their clinical utility for follow-up in patients with AEP. We prospectively screened patients who visited the emergency department for acute respiratory symptoms at the Armed Forces Capital Hospital in South Korea between February 2014 and July 2014. Of them, patients suspected to have AEP underwent an etiological investigation, including flexible bronchoscopy with bronchoalveolar lavage and TUS, and we evaluated TUS findings and serial changes on TUS during the treatment course compared with those from chest radiographs. In total, 22 patients with AEP were identified. The TUS examinations reveled that all patients exhibited multiple diffuse bilateral B-lines and lung sliding, with (n = 5) or without pleural effusion, which was consistent with alveolar-interstitial syndrome. B-line numbers fell during the course of treatment, as the lines became thinner and fainter. A-lines were evident in 19 patients on day 7 of hospitalization, when B-lines had disappeared in 13 patients, and all pleural effusion had resolved. All patients exhibited complete ultrasonic resolution by day 14, along with clinicoradiological improvement. Chest radiographs of five patients taken on day 7 seemed to show complete resolution, but several abnormal B-lines were evident on TUS performed the same day. As a result, our data show common TUS findings of AEP and suggest that AEP may be included as a differential diagnosis when multiple diffuse bilateral B-lines with preserved lung sliding are identified on a TUS examination in patients with acute symptoms, and that TUS is a useful modality for evaluating the treatment response in patients with AEP.  相似文献   
73.
In this study, we observed the effects of lipopolysaccharide (LPS) on neurodegeneration and immune response in the hippocampus. LPS is a gram-negative bacterial cell surface proteoglycan and known as a bacterial endotoxin. For this, we investigated the optimal concentration of LPS influencing the ICR mouse hippocampus to measure the LPS receptor, e.g., toll-like receptor 4 (TLR4), expression in mouse hippocampal homogenates. TLR4 expression was significantly and prominently increased in the hippocampal homogenates of the LPS (1 mg/kg)-treated group. Next, we examined pro-inflammatory response in the hippocampus using cyclooxygenase-2 (COX-2, a marker for inflammatory response) immunohistochemistry after LPS treatment. COX-2 immunoreactivity was significantly increased in the endothelium of blood vessels in the hippocampus 6 h after LPS treatment, judging from double immunofluorescence study with platelet-derived endothelial cell adhesion molecule-1 (PECAM-1, a marker for endothelial cells): it decreased 12 h and disappeared 24 h after LPS treatment. In addition, the ionized calcium-binding adapter molecule 1 (Iba-1)-immunoreactive (+) microglia were morphologically activated in the mouse hippocampus after LPS treatment. At 24 h after LPS treatment, Iba-1+ microglia of activated forms were abundant in the hippocampus. However, NeuN (a neuron-specific soluble nuclear antigen)+ neurons were not significantly changed in the hippocampus after LPS treatment. Fluoro-jade B (a marker for neuronal degeneration)+ cells were not detected in the hippocampus at any time after LPS treatment. In addition, there were no significant differences in permeability of blood–brain barriers at any time points after LPS treatment. In brief, our results indicate that intraperitoneal administration of 1 mg/kg LPS effectively induces LPS receptor (TLR4) expression in the hippocampus, and the treatment increases corticosterone levels, inflammation in the blood vessels, and microglial activation in the hippocampus without any neuronal damage.  相似文献   
74.
The β-amyloid precursor protein has been the focus of much attention from the Alzheimer's disease community for the past decade and a half. The β-amyloid precursor protein holds a pivotal position in Alzheimer's disease research because it is the precursor to the amyloid β-protein which many believe plays a central role in Alzheimer's disease pathogenesis. It was also the first gene in which mutations associated with inherited Alzheimer's disease were found. Although the molecular details of the generation of amyloid β-protein from β-amyloid precursor protein are being unraveled, the actual physiological functions of β-amyloid precursor protein are far from clear. This situation is changing as accumulating new evidence suggests that the C-terminal cytosolic tail of β-amyloid precursor protein may have multiple biological activities, ranging from axonal transport to nuclear signaling. This article reviews the current state of knowledge about the biological functions of β-amyloid precursor protein .  相似文献   
75.
We have explored the molecular pathology in 28 individuals homozygous or heterozygous for liver arginase deficiency (hyperargininemia) by a combination of Southern analysis, western blotting, DNA sequencing, and PCR. This cohort represents the majority of arginase-deficient individuals worldwide. Only 2 of 15 homozygous patients on whom red blood cells were available had antigenically cross-reacting material as ascertained by western blot analysis using anti-liver arginase antibody. Southern blots of patient genomic DNAs, cut with a variety of restriction enzymes and probed with a near-full-length (1,450-bp) human liver arginase cDNA clone, detected no gross gene deletions. Loss of a TaqI cleavage site was identified in three individuals: in a homozygous state in a Saudi Arabian patient at one site, at a different site in homozygosity in a German patient, and in heterozygosity in a patient from Australia. The changes in the latter two were localized to exon 8, through amplification of this region by PCR and electrophoretic analysis of the amplified fragment after treatment with TaqI; the precise base changes (Arg291X and Thr290Ser) were confirmed by sequencing. It is interesting that the latter nucleotide variant (Thr290Ser) was found to lie adjacent to the TaqI site rather than within it, though whether such a conservative amino acid substitution represents a true pathologic mutation remains to be determined. We conclude that arginase deficiency, though rare, is a heterogeneous disorder at the genotypic level, generally encompassing a variety of point mutations rather than substantial structural gene deletions.  相似文献   
76.
Interconversion reactions of cyclodextrin glycosyltransferase (CGTase) among cyclodextrin (CD) homologues were experimentally investigated using each CD as a substrate in an aqueous, two-phase-forming polymer solution of dextran and polyethylene glycol. Degradation rate of -CD was highest and that of -CD was lowest among -, - and -CD with Bacillus macerans CGTase. Degradation of each CD was accelerated with dextran, while decelerated with polyethylene glycol.  相似文献   
77.
Zhang  Hui  Wang  Yuexing  Deng  Ce  Zhao  Sheng  Zhang  Peng  Feng  Jie  Huang  Wei  Kang  Shujing  Qian  Qian  Xiong  Guosheng  Chang  Yuxiao 《中国科学:生命科学英文版》2022,65(2):398-411

High-quality rice reference genomes have accelerated the comprehensive identification of genome-wide variations and research on functional genomics and breeding. Tian-you-hua-zhan has been a leading hybrid in China over the past decade. Here, de novo genome assembly strategy optimization for the rice indica lines Huazhan (HZ) and Tianfeng (TF), including sequencing platforms, assembly pipelines and sequence depth, was carried out. The PacBio and Nanopore platforms for long-read sequencing were utilized, with the Canu, wtdbg2, SMARTdenovo, Flye, Canu-wtdbg2, Canu-SMARTdenovo and Canu-Flye assemblers. The combination of PacBio and Canu was optimal, considering the contig N50 length, contig number, assembled genome size and polishing process. The assembled contigs were scaffolded with Hi-C data, resulting in two “golden quality” rice reference genomes, and evaluated using the scaffold N50, BUSCO, and LTR assembly index. Furthermore, 42,625 and 41,815 non-transposable element genes were annotated for HZ and TF, respectively. Based on our assembly of HZ and TF, as well as Zhenshan97, Minghui63, Shuhui498 and 9311, comprehensive variations were identified using Nipponbare as a reference. The de novo assembly strategy for rice we optimized and the “golden quality” rice genomes we produced for HZ and TF will benefit rice genomics and breeding research, especially with respect to uncovering the genomic basis of the elite traits of HZ and TF.

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78.
The CC chemokine receptor 7 (CCR7) and cognate CCR7 ligands, CCL19 and CCL21, help establish microenvironments in lymphoid tissue that can facilitate encounters between naive T cells and mature dendritic cells (DCs). This study was conducted to determine if CCR7 ligands can augment the immunogenicity of a DNA vaccine that expresses glycoprotein B (gB) of the pseudorabies virus (PrV). The genetic co-transfer of CCR7 ligands along with a PrV DNA vaccine increased the levels of serum PrV-specific immunoglobulin (Ig) G by 2- to 2.5-fold. In addition, the level of PrV-specific IgG2a isotype was significantly enhanced by co-injection of CCR7 ligand DNA, which indicates that CCR7 ligand biases the humoral immunity toward the Th1-type pattern. The co-injection of CCR7 ligand DNA consistently enhanced the level of Th1-type cytokines (IL-2 and IFN-gamma) produced by stimulated immune cells when compared with a group that was vaccinated with the PrV DNA vaccine. Also, the genetic co-transfer of CCR7 ligand DNAs with PrV DNA vaccine provided prolonged survival against a virulent challenge by PrV. Moreover, the co-administration of CCR7 ligand DNA increased the number of mature DCs into the secondary lymphoid tissues, which appeared to enhance the proliferation of PrV-immune CD4(+) T cells. Taken together, these findings indicate that CCR7 ligands are an attractive adjuvant for a PrV DNA vaccine that can offer protective immunity against the PrV.  相似文献   
79.
Viruses including baculoviruses are obligatory parasites, as their genomes do not encode all the proteins required for replication. Therefore, viruses have evolved to exploit the behavior and the physiology of their hosts and often eoevolved with their hosts over millions of years. Recent comparative analyses of complete genome sequences of baculoviruses revealed the patterns of gene acquisitions and losses that have occurred during baculovirus evolution. In addition, knowledge of virus genes has also provided understanding of the mechanism of baculovirus infection including replication, species-specific virulence and host range. The Bm8 gene of Bombyx mori nucleopolyhedrovirus (NPV) and its homologues are found only in group I NPV genomes. The Autographa californica NPV Acl6 gene is a homologue of Bm8 and, encodes a viral structural protein. It has been shown that Bm8/Ac 16 interacts with baculoviral and cellular proteins. Bm8/Ac 16 interacts with baculoviral IE1 that is facilitated by coiled coil domains, and the interaction with IE1 is important for Bin8 function. Ac16 also forms a complex with viral FP25 and cellular actin and associates with membranes via palmitoylation. These data suggested that this gene family encodes a multifunctional protein that accomplishes specific needs of group INPVs.  相似文献   
80.
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