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1.
本研究对2018至2021年采集的9号巢鼠(Micromys minutus)标本、22号红耳巢鼠(M. erythrotis)标本和19号待厘定的巢鼠属标本,进行形态分类和分子系统学分析,进一步揭示我国巢鼠属的分类和系统分化问题。待厘定的巢鼠属标本形态特征为:标本体背毛黑棕,体腹毛基灰色,毛尖灰白,体侧毛色具明显区分,尾背部毛色黑棕,尾腹部毛色灰棕色;尾长长于头体长的120%;头骨背面观可见颧弓明显弯曲;颅全长[(18.59 ± 0.48)mm]和颅基长[(17.43 ± 0.48 mm)]较长,腭长[(9.35 ± 0.11)mm]较长,脑颅高[(7.43 ± 0.06)mm]较高。待厘定的巢鼠属标本形态特征与巢鼠和红耳巢鼠均存在差异。待厘定巢鼠属标本与巢鼠和红耳巢鼠之间的遗传距离分别为0.115和0.136,接近于巢鼠与红耳巢鼠之间的遗传距离(0.126)。利用Cyt b基因全序列和核基因IRBP1、RAG1和RAG2序列分别构建的巢鼠属系统发生树均以较高的置信度分化成3个进化支,即巢鼠、红耳巢鼠和待厘定的巢鼠属样本的进化支。形态学和分子系统学分析结果均支持待厘定的巢鼠属标本为独立物种分类单元,对应于文献记载的巢鼠川西亚种(M. m. pygmaeus)。根据产地、遗传距离和形态分化,建议将巢鼠川西亚种提升为种,命名为川西巢鼠(M. pygmaeus comb. nov.)。利用Cyt b基因全序列构建的巢鼠系统发生树分化成6个进化谱系:日韩谱系、欧洲谱系、俄罗斯新西伯利亚谱系、中国东北和俄罗斯远东谱系、中国安徽谱系和中国台湾谱系。  相似文献   
2.
The specificity and regulation of GSK3β are thought to involve in the docking interactions at core kinase domain because of the particular amino acid residues. Recent X-ray diffraction studies illuminated the relative binding residues on AxinGID and FRATtide for GSK3β docking and appeared that GSK3β Val267Gly (V267G) and Tyr288Phe (Y288F) could distinguish the direct interaction between AxinGID and FRATtide. In order to explore the mode that involved the binding of GSKIP to GSK3β and compare it with that of AxinGID and FRATtide, we pinpointed the binding sites of GSKIP to GSK3β through the single-point mutation of four corresponding sites within GSK3β (residues 260–300) as scaffold-binding region I (designated SBR-I260–300). Our data showed that these three binding proteins shared similar binding sites on GSK3β. We also found that the binding of GSK3β V267G mutant to GSKIP and AxinGID, but not that of Y288F mutant (effect on FRATtide), was affected. Further, based on the simulation data, the electron-density map of GSKIPtide bore closer similarity to the map AxinGID than to that of FRATtide. Interestingly, many C-terminal helix region point-mutants of GSK3β L359P, F362A, E366K, and L367P were able to eliminate the binding with FRATtide, but not AxinGID or GSKIP. In addition, CABYR exhibited a unique mode in binding to C-terminal helix region of GSK3β. Taken together, our data revealed that in addition to the core kinase domain, SBR-I260–300, another novel C-terminus helix region, designated SBR-II339–383, also appeared to participate in the recognition and specificity of GSK3β in binding to other specific proteins.  相似文献   
3.
在贵州省六盘水市杨梅乡慕尼克村,利用陷阱法捕捉到3号麝鼩属(Crocidura)标本。本次采集标本的体形较小,头体长(49.0 ± 0.8)mm,尾长[(41.8 ± 4.2)mm]略短于头体长(尾长/头体长为85%)。背毛呈浅灰褐色,腹毛颜色浅于背毛,呈灰色。尾部双色,背侧黑褐色,腹侧淡于背侧。前足背部白色,后足则为淡灰色。尾近乎裸露,尾基约1/3着生稀疏白色长毛。颅全长(15.92 ± 0.55)mm,脑颅高(4.75 ± 0.18)mm。上门齿1枚,有一长而大的前尖和一小而矮的后尖。上单尖齿3枚,第1单尖齿最大,第2单尖齿略大于第3单尖齿,1枚第四前臼齿(P4),3枚臼齿。上述特征与东阳江麝鼩(C. dongyangjiangensis)模式标本的描述和鉴定特征基本一致,因此将3号采集标本鉴定为东阳江麝鼩。基于Cyt b基因进行分子系统发育分析,采集标本与麝鼩属物种中的东阳江麝鼩遗传距离最近,在0.004 ~ 0.027之间。系统发生树显示,3号标本与东阳江麝鼩构成一个单系进化分支,进一步证实本次采集的3号标本是东阳江麝鼩,为贵州省分布新记录种。  相似文献   
4.
In this study, we designed a simple and rapid colorimetric detection method, a one-tube loop-mediated isothermal amplification (LAMP)-PCR-hybridization-restriction endonuclease-ELISA [one-tube LAMP-PCR-HY-RE-ELISA] system, to detect resistance to isoniazid, ethambutol and streptomycin in strains of Mycobacterium tuberculosis isolated from clinical specimens. The clinical performance of this method for detecting isoniazid-resistant, ethambutol-resistant and streptomycin-resistant isolates of M. tuberculosis showed 98.9%, 94.3% and 93.8%, respectively. This assay is rapid and convenient that can be performed within one working day. One-tube LAMP-PCR-HY-RE-ELISA system was designed based on hot spot point mutations in target drug-resistant genes, using LAMP-PCR, hybridization, digestion with restriction endonuclease and colorimetric method of ELISA. In this study, LAMP assay was used to amplify DNA from drug-resistant M. tuberculosis, and ELISA was used for colorimetrical determination. This assay will be a useful tool for rapid diagnosis of mutant codons in strains of M. tuberculosis for isoniazid at katG 315 and katG 463, ethambutol at embB 306 and embB 497, and streptomycin at rpsL 43.  相似文献   
5.
Male infertility affects approximately 50% of all infertile couples. The male-related causes of intracytoplasmic sperm injection failure include the absence of sperm, immotile or immature sperm, and sperm with structural defects such as those caused by premature chromosomal condensation and DNA damage. Our previous studies based on a knockout mice model indicated that SEPT12 proteins are critical for the terminal morphological formation of sperm. SEPT12 mutations in men result in teratozospermia and oligozospermia. In addition, the spermatozoa exhibit morphological defects of the head and tail, premature chromosomal condensation, and nuclear damage. However, the molecular functions of SEPT12 during spermatogenesis remain unclear. To determine the molecular functions of SEPT12, we applied a yeast 2-hybrid system to identify SEPT12 interactors. Seven proteins that interact with SEPT12 were identified: SEPT family proteins (SEPT4 and SEPT6), nuclear or nuclear membrane proteins (protamine 2, sperm-associated antigen 4, and NDC1 transmembrane nucleoproine), and sperm-related structural proteins (pericentriolar material 1 and obscurin-like 1). Sperm-associated antigen 4 (SPAG4; also known as SUN4) belongs to the SUN family of proteins and acts as a linker protein between nucleoskeleton and cytoskeleton proteins and localizes in the nuclear membrane. We determined that SEPT12 interacts with SPAG4 in a male germ cell line through coimmunoprecipitation. During human spermiogenesis, SEPT12 is colocalized with SPAG4 near the nuclear periphery in round spermatids and in the centrosome region in elongating spermatids. Furthermore, we observed that SEPT12/SPAG4/LAMINB1 formed complexes and were coexpressed in the nuclear periphery of round spermatids. In addition, mutated SEPT12, which was screened from an infertile man, affected the integration of these nuclear envelope complexes through coimmunoprecipitation. This was the first study that suggested that SEPT proteins link to the SUN/LAMIN complexes during the formation of nuclear envelopes and are involved in the development of postmeiotic germ cells.  相似文献   
6.
Viral vector transfection systems are among the simplest of biological agents with the ability to transfer genes into the central nervous system.In brain research,a series of powerful and novel gene editing technologies are based on these systems.Although many viral vectors are used in rodents,their full application has been limited in non-human primates.To identify viral vectors that can stably and effectively express exogenous genes within nonhuman primates,eleven commonly used recombinant adeno-associated viral and lentiviral vectors,each carrying a gene to express green or red fluorescence,were injected into the parietal cortex of four rhesus monkeys.The expression of fluorescent cells was used to quantify transfection efficiency.Histological results revealed that recombinant adeno-associated viral vectors,especially the serotype 2/9 coupled with the cytomegalovirus,human synapsin Ⅰ,or Ca2+/calmodulin-dependent protein kinase Ⅱ promoters,and lentiviral vector coupled with the human ubiquitin C promoter,induced higher expression of fluorescent cells,representing high transfection efficiency.This is the first comparison of transfection efficiencies of different viral vectors carrying different promoters and serotypes in non-human primates (NHPs).These results can be used as an aid to select optimal vectors to transfer exogenous genes into the central nervous system of non-human primates.  相似文献   
7.
Norathyriol, aglycone of a xanthone C-glycoside mangiferin isolated from Tripterospermum lanceolatum, concentration dependently inhibited the formylmethionyl-leucyl-phenylalanine (fMLP)-induced superoxide anion (O2˙−) generation and O2 consumption in rat neutrophils. In cell-free oxygen radical generating system, norathyriol inhibited the O2˙− generation during dihydroxyfumaric acid (DHF) autoxidation and in hypoxanthine-xanthine oxidase system. fMLP-induced transient elevation of [Ca2+]i and the formation of inositol trisphosphate (IP3) were significantly inhibited by norathyriol (30 μM) (about 30 and 46% inhibition, respectively). Norathyriol concentration dependently suppressed the neutrophil cytosolic phospholipase C (PLC). In contrast with the marked attenuation of fMLP-induced protein tyrosine phosphorylation (about 70% inhibition at 10 μM norathyriol), norathyriol only slightly modulated the phospholipase D (PLD) activity as determined by the formation of phosphatidic acid (PA) and, in the presence of ethanol, phosphatidylethanol (PEt). Norathyriol did not modulate the intracellular cyclic AMP level. In the presence of NADPH, the phorbol 12-myristate 13-acetate (PMA)-activated particulate NADPH oxidase activity was suppressed by norathyriol in a concentration-dependent manner and the inhibition was noncompetitive with respect to NADPH. Norathyriol inhibited the iodonitrotetrazolium violet (INT) reduction in arachidonic acid (AA)-activated cell-free NADPH oxidase system at the same concentration range as those used in the suppression of PMA-activated particulate NADPH oxidase activity. Taken together, these results suggest that the scavenging ability of norathyriol contributes to the reduction of generated O2˙−, however, the inhibition of O2˙− generation from neutrophils by norathyriol is attributed to the blockade of PLC pathway, the attenuation of protein tyrosine phosphorylation, and to the suppression of NADPH oxidase through the interruption of electrons transport.  相似文献   
8.

Background

Investigating the factors related to suicide is crucial for suicide prevention. Psychiatric disorders, gender, socioeconomic status, and catastrophic illnesses are associated with increased risk of suicide. Most studies have typically focused on the separate influences of physiological or psychological factors on suicide-related behaviors, and have rarely used national data records to examine and compare the effects of major physical illnesses, psychiatric disorders, and socioeconomic status on the risk of suicide-related behaviors.

Objectives

To identify the characteristics of people who exhibited suicide-related behaviors and the multiple factors associated with repeated suicide-related behaviors and deaths by suicide by examining national data records.

Design

This is a cohort study of Taiwan’s national data records of hospitalized patients with suicide-related behaviors from January 1, 1997, to December 31, 2010.

Participants

The study population included all people in Taiwan who were hospitalized with a code indicating suicide or self-inflicted injury (E950–E959) according to the International Classification of Disease, Ninth Revision, Clinical Modification.

Results

Self-poisoning was the most common method of self-inflicted injury among hospitalized patients with suicide-related behaviors who used a single method. Those who were female, had been hospitalized for suicide-related behaviors at a younger age, had a low income, had a psychiatric disorder (i.e., personality disorder, major depressive disorder, bipolar disorder, schizophrenia, alcohol-related disorder, or adjustment disorder), had a catastrophic illness, or had been hospitalized for suicide-related behaviors that involved two methods of self-inflicted injury had a higher risk of hospitalization for repeated suicide-related behaviors. Those who were male, had been hospitalized for suicide-related behaviors at an older age, had low income, had schizophrenia, showed repeated suicide-related behaviors, had a catastrophic illness, or had adopted a single lethal method had an increased risk of death by suicide.

Conclusions

High-risk factors should be considered when devising suicide-prevention strategies.  相似文献   
9.
利用光学显微镜对山东堇菜属Viola L.20种2变种植物的叶上、下表皮微形态进行了研究。结果表明,该属植物叶表皮细胞为多边形或不规则形,垂周壁为波形、浅波形或平直弓形,气孔器为不等型(偶上表皮兼有平列型)。根据其上表皮是否具有平列型气孔器,可将其分为两个类型,即①上表皮有平列型气孔器,如三色堇;②上表皮无平列型气孔器,如该属绝大多数植物。类型②又根据叶表皮细胞形状和垂周壁式样之不同,进一步划分为4个亚类型。表皮细胞形状和垂周壁式样对该属内种、变种的鉴定具有重要的意义。不赞成将早开堇菜、茜堇菜合并到紫花地丁;不支持将阴地堇菜作为蒙古堇菜的鉴定;不支持将泰山堇菜合并到早开堇菜、将总裂叶堇菜降为裂叶堇菜的变种。  相似文献   
10.

Background

This study was conducted to investigate an outbreak caused by imipenem-resistant Acinetobacter baumannii (IRAB) in a medical intensive care unit (ICU) in a regional hospital.

Methods

In response to an IRAB outbreak from October 2012 to February 2013, we developed several infection control measures, including an extensive review process of environmental cleaning and disinfection, and used molecular methods to identify each clinical and environmental IRAB isolate.

Results

During this five-month period, 22 patients were colonized with IRAB and 18 patients had IRAB infections. The in-hospital mortality rate was significantly higher among patients with infections rather than colonizations (44.4% vs 9.1%, p = 0.028). Additionally, nine environmental specimens, including five specimens collected after terminal disinfection, were positive for IRAB. 12 environmental isolates and 28 of 36 available clinical isolates belonged to one unique pulsotype A, which was confirmed by molecular methods. We found the concentration of disinfectant, 0.08% sodium hypochlorite, was inadequate. After correcting the environmental cleansing methods, the surveillance study showed no further IRAB isolates on the control panel surfaces of the medical equipment or in patients in the ICU. Additionally, an in vitro study of IRAB immersed in different concentrations of sodium hypochlorite showed that 0.5% sodium hypochlorite eradicates IRAB after 30 seconds of inoculation, but 0.08% sodium hypochlorite only reduces the bacterial load.

Conclusions

This study highlights the importance of the preparation of disinfectants to adequately achieve environmental disinfection in the control of IRAB outbreaks in the ICU.  相似文献   
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