龈沟液CRP、IL-17、RANKL与种植体周围炎患者牙周临床指标的相关性分析及其联合检测对治疗后预后的评估价值

摘要 目的：分析龈沟液C反应蛋白（CRP）、白细胞介素-17（IL-17）及核因子-kB受体活化因子配体（RANKL）与种植体周围炎（PI）患者牙周临床指标的相关性及探讨其联合检测对治疗后预后的评估价值。方法：选取2018年1月～2022年1月我院收治的80例PI患者,记作炎症组。另取同期种植体健康患者80例作为健康组。检测并比较两组龈沟液CRP、IL-17及RANKL水平,牙周临床指标。并以Pearson相关性分析龈沟液CRP、IL-17及RANKL与牙周临床指标的相关性。此外,将所有PI患者按照急性生理学与慢性健康状况评分Ⅱ（APACHE Ⅱ）评分的差异分为预后良好组27例与预后不良组53例,比较两组龈沟液CRP、IL-17及RANKL水平。通过受试者工作特征（ROC）曲线分析上述三项指标联合预测PI患者治疗后预后不良的效能。结果：炎症组龈沟液CRP、IL-17及RANKL水平均高于健康组（均P＜0.05）。炎症组改良牙龈指数（mGI）、改良龈沟出血指数（mSBI）评分以及探诊深度（PD）均高于健康组（均P＜0.05）。经Pearson相关性分析发现,龈沟液CRP、IL-17及RANKL水平与mGI、mSBI评分及PD均呈正相关关系（均P＜0.05）。预后不良组龈沟液CRP、IL-17及RANKL水平均高于预后良好组（均P＜0.05）。经ROC曲线分析发现,龈沟液CRP、IL-17及RANKL联合预测PI患者治疗后预后不良的曲线下面积（0.95CI）为0.851（0.752～0.944）,优于上述三项指标单独预测。结论：龈沟液CRP、IL-17及RANKL与PI患者mGI、mSBI评分以及PD均密切相关,检测三指标有助于评估患者病情及治疗后预后。     

二甲胺四环素联合茶多酚对早期种植体周围软组织炎患者牙周指标、炎性因子以及龈沟液RANKL、Shh水平的影响

摘要 目的：探讨二甲胺四环素联合茶多酚对早期种植体周围软组织炎患者牙周指标、炎性因子以及龈沟液核因子-?资?茁受体活化因子配体（RANKL）、音猬因子（Shh）水平的影响。方法：将106例于我院就诊的早期种植体周围软组织炎患者纳入研究,以信封抽签法分为对照组（n=53,二甲胺四环素治疗）和研究组（n=53,二甲胺四环素联合茶多酚治疗）。对比两组患者治疗前、治疗4周后的牙周指标、炎性因子、疗效以及龈沟液RANKL、Shh水平,记录两组治疗期间不良反应情况。结果：治疗4周后研究组临床总有效率90.57%（48/53）高于对照组73.58%（39/53）（P<0.05）。两组不良反应发生率对比无差异（P>0.05）。两组治疗4周后改良菌斑指数（mPLI）、改良龈沟出血指数（mSBI）、种植体周袋探诊深度（PPD）和血清白介素-1β（IL-1β）、单核细胞趋化蛋白-1(MCP-1)水平以及龈沟液RANKL、Shh水平均下降,且研究组低于对照组（P<0.05）。结论：二甲胺四环素联合茶多酚治疗早期种植体周围软组织炎患者,疗效显著,可有效改善患者牙周情况,降低患者血清IL-1β、MCP-1水平以及龈沟液RANKL、Shh水平,安全可靠。     

慢性牙周炎伴咬合创伤患者龈沟液Sclerostin、SLIT3与牙周临床指标和RANKL-OPG系统的相关性研究

摘要 目的：探讨慢性牙周炎伴咬合创伤患者龈沟液骨硬化蛋白（Sclerostin）、神经轴突导向因子3（SLIT3）与牙周临床指标和核因子-κb受体活化因子配体（RANKL）-骨保护蛋白（OPG）系统的相关性。方法：选择2021年1月至2023年1月我院收治的123例慢性牙周炎伴咬合创伤患者（创伤组）和101例不伴咬合创伤的慢性牙周炎患者（对照组）。治疗前,检测龈沟液中Sclerostin、SLIT3、RANKL、OPG水平,计算RANKL/OPG比值,评估临床牙周指标出血指数（SBI）、菌斑指数（PLI）、探诊深度（PD）、附着丧失（AL）。分析Sclerostin、SLIT3与牙周临床指标、RANKL、OPG、RANKL/OPG之间的相关性。结果：创伤组治疗前龈沟液中Sclerostin、SLIT3、RANKL水平,RANKL/OPG,PLI、SBI、AL、PD高于对照组（P＜0.05）,OPG低于对照组（P＜0.05）。创伤组治疗前龈沟液中Sclerostin、SLIT3与PLI、SBI、AL、PD、RANKL、RANKL/OPG呈正相关（P＜0.05）,与OPG呈负相关（P＜0.05）。结论：慢性牙周炎伴咬合创伤患者龈沟液中Sclerostin、SLIT3水平显著增高,且与牙周临床指标异常、RANKL/OPG增加有关。     

2型糖尿病伴慢性牙周炎患者龈沟液Omentin-1、MMP-9、OPG/RANKL比值与牙周指标、氧化应激和NLRP3炎症小体的关系

摘要 目的：探讨2型糖尿病（T2DM）伴慢性牙周炎（CP）患者龈沟液网膜素-1（Omentin-1）、基质金属蛋白酶-9（MMP-9）、骨保护素（OPG）/细胞核因子κB受体活化因子配体（RANKL）比值与牙周指标、氧化应激和核苷酸结合寡聚化结构域样受体蛋白3（NLRP3）炎症小体的关系。方法：选择2020年6月至2022年6月首都医科大学附属北京康复医院收治的73例T2DM患者（T2DM组）,77例CP患者（CP组）,83例T2DM伴CP患者（T2DM伴CP组）。检测所有患者龈沟液中Omentin-1、MMP-9、OPG/RANKL比值,分析其与牙周指标、氧化应激和NLRP3炎症小体相关分子信使核糖核酸（mRNA）表达的相关性。结果：T2DM伴CP组龈沟液中Omentin-1,OPG/RANKL比值、总抗氧化能力（TAC）、超氧化物歧化酶（SOD）低于T2DM组和CP组（P＜0.05）,MMP-9、丙二醛（MDA）、NLRP3mRNA、凋亡相关斑点样蛋白（ASC）mRNA、半胱氨酸蛋白酶-1（caspase-1）mRNA表达以及出血指数（SBI）、菌斑指数（PLI）、牙周袋探诊深度（PD）、附着丧失（AL）高于T2DM组和CP组（P＜0.05）。T2DM伴CP患者龈沟液中Omentin-1、OPG/RANKL比值与TAC、SOD呈正相关（P＜0.05）,与MDA、NLRP3mRNA、ASC mRNA、caspase-1mRNA表达以及PLI、SBI、AL、PD呈负相关（P＜0.05）,MMP-9与TAC、SOD呈负相关（P＜0.05）,与MDA、NLRP3mRNA、ASC mRNA、caspase-1mRNA表达以及PLI、SBI、AL、PD呈正相关（P＜0.05）。结论：T2DM伴CP患者龈沟液中Omentin-1水平、OPG/ RANKL比值降低,MMP-9水平升高,与牙周组织破坏加重、氧化应激、NLRP3炎症小体激活有关。     

龈沟液miR-155、miR-223表达水平与慢性牙周炎伴2型糖尿病患者牙周临床指标、口腔龈下菌群以及Th17/Treg失衡的相关性分析

摘要 目的：探讨龈沟液miR-155、miR-223表达水平与慢性牙周炎伴2型糖尿病（T2DM）患者牙周临床指标、口腔龈下菌群以及外周血辅助性T细胞17（Th17）/调节性T细胞（Treg）失衡的相关性。方法：选择2018年1月至2022年1月安徽理工大学第一附属医院口腔科收治的86例慢性牙周炎患者,根据是否伴T2DM将患者分为慢性牙周炎伴T2DM组15例和单纯慢性牙周炎组71例,另选择65例健康体检志愿者为对照组。检测龈沟液miR-155、miR-223表达水平,口腔龈下菌群以及外周血Th17细胞占比、Treg细胞占比、血清白细胞介素（IL）-17、转化生长因子-β（TGF-β）水平。Pearson相关分析龈沟液miR-155、miR-223表达水平与牙周临床指标、口腔龈下菌群、外周血Th17/Treg以及血清IL-17、TGF-β的相关性。结果：慢性牙周炎伴T2DM组、单纯慢性牙周炎组龈沟液miR-155、miR-223表达水平高于对照组（P＜0.05）,且慢性牙周炎伴T2DM组高于单纯慢性牙周炎组（P＜0.05）。慢性牙周炎伴T2DM组龈沟出血指数（SBI）、菌斑指数（PLI）、探诊深度（PD）、附着丧失（AL）、牙龈卟啉单胞菌、二氧化碳噬纤维菌、中间普氏菌、变黑普氏菌数量、外周血Th17细胞占比、Th17/Treg比值、血清IL-17水平高于单纯慢性牙周炎组（P＜0.05）,外周血Treg细胞占比低于单纯慢性牙周炎组（P＜0.05）。龈沟液miR-155、miR-223表达水平与PLI、SBI、AL、PD、牙龈卟啉单胞菌、二氧化碳噬纤维菌、中间普氏菌、变黑普氏菌数量、外周血Th17细胞占比、Th17/Treg比值、血清IL-17水平呈正相关（P＜0.05）,与外周血Treg细胞占比呈负相关（P＜0.05）。结论：慢性牙周炎伴T2DM患者龈沟液中miR-155、miR-233表达均上调,且与牙周组织破坏程度、龈下菌群紊乱和Th17/Treg失衡有关。     

早产儿血清炎性因子与生长发育指标的关系及对新生儿呼吸窘迫综合征的预测研究

摘要 目的：分析早产儿血清炎性因子与生长发育指标的关系及对新生儿呼吸窘迫综合征（RDS）的预测效能。方法：选择2018年1月至2020年10月在我院出生的98例早产儿作为研究对象,根据是否并发RDS,分为RDS组（58例）和非RDS组（40例）。检测两组血清白细胞介素-1β（IL-1β）、IL-6、IL-8、肿瘤坏死因子-α（TNF-α）、降钙素原（PCT）水平,记录生长发育指标,通过Pearson相关性分析早产儿血清炎性因子与生长发育指标的关系,使用受试者工作特征曲线（ROC）分析血清炎性因子对新生儿呼吸窘迫综合征的预测效能。结果：RDS组血清IL-1β、IL-6、IL-8、TNF-α、PCT水平均高于非RDS组（P＜0.05）;RDS组胎龄、出生体重均小于非RDS组（P＜0.05）;经Pearson相关性分析,早产儿血清IL-1β、IL-6、IL-8、TNF-α、PCT水平均与胎龄、出生体重呈负相关（P＜0.05）;经多因素Logistic回归分析,IL-1β、IL-6、IL-8、TNF-α、PCT均是早产儿并发新生儿呼吸窘迫综合征的独立危险因素（P＜0.05）;经ROC曲线分析,IL-1β、IL-6、IL-8、TNF-α联合PCT预测早产儿并发新生儿呼吸窘迫综合征的AUC为0.910。结论：早产儿血清IL-1β、IL-6、IL-8、TNF-α均与胎龄及出生体重密切相关,这些炎性因子联合预测RDS发生的效能较好,值得临床予以重视应用。     

血清IL-17、IL-32、IL-33、IL-37联合检测对初治多发性骨髓瘤患者早期治疗反应性的预测价值

摘要 目的：探讨血清白细胞介素-17（IL-17）、白细胞介素-32（IL-32）、白细胞介素-33（IL-33）、白细胞介素-37（IL-37）联合检测对接受硼替佐米为基础一线治疗方案的初治多发性骨髓瘤（MM）患者早期治疗反应性的预测价值。方法：选择2018年7月至2021年3月期间陕西省人民医院收治的初治MM患者176例为研究对象,所有患者均接受以硼替佐米为基础一线的治疗方案,根据早期治疗反应性分为敏感组（142例）和非敏感组（34例）;采用酶联免疫吸附法检测并比较两组血清IL-17、IL-32、IL-33、IL-37水平,并分析其联合检测对早期治疗反应性的预测价值。结果：敏感组治疗前血清IL-17、IL-32水平低于非敏感组,IL-33、IL-37水平高于非敏感组（P＜0.05）。多因素logistic回归分析显示,年龄≥65岁、血清IL-17≥29.70 pg/mL、IL-32≥63.02 ng/L、肿瘤分期III期是早期治疗反应性的危险因素（P＜0.05）,IL-33＞141.97 pg/mL、IL-37＞69.17 ng/L是保护因素（P＜0.05）。血清IL-17、IL-32、IL-33、IL-37联合检测预测早期治疗反应性的曲线下面积（AUC）为0.866（95%CI：0.801~0.972）。结论：年龄、肿瘤分期、血清IL-17、IL-32、IL-33、IL-37是MM患者早期治疗反应性的影响因素,联合检测血清IL-17、IL-32、IL-33、IL-37水平对接受硼替佐米为基础一线治疗方案的初治MM患者早期治疗反应性预测价值较高。     

黄连上清胶囊联合康复新液治疗口腔种植体周围软组织炎的临床研究

摘要 目的：观察黄连上清胶囊联合康复新液治疗口腔种植体周围软组织炎（PI）的临床治疗效果。方法：选择兰州大学第二医院2018年3月~2021年5月期间收治的口腔PI患者100例作为观察对象,所有患者根据双色球法分为对照组（50例）和观察组（50例）,对照组患者接受康复新液治疗,观察组患者接受黄连上清胶囊联合康复新液治疗,对比两组疗效、牙周功能指标、血清细胞因子和不良反应。结果：观察组的临床总有效率高于对照组（P<0.05）。两组不良反应发生率对比无差异（P>0.05）。治疗后,两组龈沟出血指数（SBI）、菌斑指数（PLI）、附着丧失（AL）、探诊深度（PD）减小,且观察组低于对照组（P<0.05）。治疗后,两组白介素-1β（IL-1β）、白介素-6（IL-6）和单核细胞趋化因子（MCP-1）水平下降,且观察组低于对照组（P<0.05）。结论：黄连上清胶囊联合康复新液治疗口腔PI,可促进牙周功能恢复,减轻种植体周围炎症,安全可靠。     

无托槽隐形矫治器与固定矫治器对牙周病正畸治疗患者龈下菌群、龈沟液炎症因子和氧化应激的影响

摘要 目的：对比固定矫治器与无托槽隐形矫治器对牙周病正畸治疗患者龈沟液炎症因子、龈下菌群和氧化应激的影响。方法：选取2016年1月～2021年10月于河北省眼科医院口腔正畸科接受正畸治疗的112例牙周病患者,根据矫治器的不同分为对照组（固定矫治器,n=54）和实验组（无托槽隐形矫治器,n=58）。对比两组牙周健康指标、龈下菌群、龈沟液炎症因子、氧化应激指标和疼痛评分的变化情况。结果：两组矫治10个月后牙龈指数、菌斑指数、龈沟出血指数、牙周探诊深度下降,且实验组低于对照组（P<0.05）。实验组矫治10个月后牙龈卟啉单胞菌（Pg）、具核梭杆菌（Fn）、福塞斯坦氏菌（Tf）和中间型普里沃菌（Pi）含量低于对照组（P<0.05）。两组矫治10个月后肿瘤坏死因子-α（TNF-α）、白细胞介素-6（IL-6）、白细胞介素1β（IL-1β）下降,且实验组低于对照组（P<0.05）。两组矫治10个月后丙二醛（MDA）、活性氧（ROS）水平下降,且实验组低于对照组;超氧化物歧化酶（SOD）升高,且实验组高于对照组（P<0.05）。两组矫治1 d、7 d后疼痛视觉模拟评分（VAS）评分升高后下降,且实验组低于对照组（P<0.05）。结论：无托槽隐形矫治器与固定矫治器对牙周病正畸治疗患者均有较好的疗效,其中无托槽隐形矫治器在改善牙周健康指标、龈下菌群、龈沟液炎症因子和氧化应激等方面的效果较为显著。     

双波长激光联合米诺环素对慢性牙周炎牙周临床指标及龈沟液IL-6、IL-8、IL-17、TNF-α水平的影响

摘要 目的：探讨双波长激光联合米诺环素对慢性牙周炎牙周临床指标及龈沟液白细胞介素（IL）-6、IL-8、IL-17、肿瘤坏死因子（TNF）-α水平的影响。方法：回顾性分析2018年5月至2020年12月长沙市第三医院口腔科收治的90例慢性牙周炎患者的诊治资料。根据治疗方法的不同,将患者分为龈下刮治及根面平整术（SRP）组、双波长激光（DWL）组和双波长激光联合米诺环素（DWL+M）组,每组均30例。比较各组的治疗效果,治疗前及治疗后三个月的牙周临床指标：牙龈指数（GI）、龈沟出血指数（SBI）、探针深度（PD）、临床附着丧失（CAL）,龈沟液的炎性因子水平：IL-6、IL-8、IL-17、TNF-α,并记录各组的不良反应情况。结果：DWL+M组总有效率依次高于DWL组、SRP组,差异有统计学意义（P<0.05）。三组治疗后三个月的GI、SBI、PD、CAL均低于治疗前,DWL+M组治疗后三个月的GI、SBI、PD、CAL均低于同期的SRP组和DWL组（P<0.05）。治疗后三个月三组龈沟液IL-6、IL-8、IL-17、TNF-α水平较治疗前降低,DWL+M组治疗后三个月的IL-6、IL-8、IL-17、TNF-α水平均低于同期的SRP组和DWL组,差异均有统计学意义（P<0.05）。三组患者在治疗过程中均未发生不良反应。结论：慢性牙周炎患者采用双波长激光联合米诺环素治疗能使牙周炎症、临床症状明显减轻,且具有较高的安全性。     

ATP/ADP exchange activity of gastric (H+ + K+)-ATPase

The ATP/ADP exchange is shown to be a partial reaction of the $\text{(}\text{H}{}^{\mathrm{+}}\text{+}\text{K}{}^{\mathrm{+}}\text{)-}\text{ATPase}$ by the absence of measurable nucleoside diphosphokinase activity and the insensitivity of the reaction to $\text{P}{}^1$, $\text{P}{}^5$ -di(adenosine-5′) pentaphosphate, a myokinase inhibitor. The exchange demonstrates an absolute requirement for Mg²⁺ and is optimal at an ADP/ATP ratio of 2. The high ATP concentration ($\text{K}{}_{0.5}\text{= 116 μ}\text{M}$) required for maximal exchange is interpreted as evidence for the involvement of a low affinity form of nucleotide site. The ATP/ADP exchange is regarded as evidence for an ADP-sensitive form of the phosphoenzyme. In native enzyme, pre-steady state kinetics show that the formation of the phosphoenzyme is partially sensitive to ADP while modification of the enzyme by pretreatment with 5,5′-dithiobis(2-nitrobenzoic acid) (DTNB) in the absence of Mg²⁺ results in a steady-state phosphoenzyme population, a component of which is ADP sensitive. The ATP/ADP exchange reaction can be either stimulated or inhibited by the presence of K⁺ as a function of pH and Mg²⁺.     

AutoFACT: AnAutomaticFunctionalAnnotation andClassificationTool

Background  

Assignment of function to new molecular sequence data is an essential step in genomics projects. The usual process involves similarity searches of a given sequence against one or more databases, an arduous process for large datasets.     

Characterization of cytochrome P-450SCC-containing liposomes

Purified cytochrome $\text{P}{}_{\mathrm{<mtext>450</mtext><mtext>SCC</mtext>}}$ from bovine adrenocortical mitochondria was incorporated into liposomes by the cholate-dilution method utilizing either dialysis or Sephadex gel filtration. Among synthetic phospholipids tested, dioleoylglycerophosphocholine showed the best stability during the incorporation of $\text{P}{}_{\mathrm{<mtext>450</mtext><mtext>SCC</mtext>}}$ into liposomes. A maximum amount of heme was incorporated into liposomes at a molar ratio of phospholipid to the cytochrome of approx. 200. When $\text{P}{}_{\mathrm{<mtext>450</mtext><mtext>SCC</mtext>}}$ was incorporated into the dioleoylglycerophosphocholine liposomes by the cholate-filtration method, the $\text{P}{}_{\mathrm{<mtext>450</mtext><mtext>SCC</mtext>}}\text{-}\text{containing liposomes}$ showed two major populations on the elution pattern of the Sepharose 4B gel filtration, and were seen at a diameter of 200–600 Å and its aggregated forms. When the cytochrome was incorporated into dioleoylglycerophosphocholine liposomes or cholesterol-free adrenocortical mitochondrial liposomes, $\text{P}{}_{\mathrm{<mtext>450</mtext><mtext>SCC</mtext>}}$ was less stable than $\text{P}{}_{\mathrm{<mtext>450</mtext><mtext>SCC</mtext>}}$ in aqueous solution. Cholesterol or adrenodoxin markedly stabilized the liposomal $\text{P}{}_{\mathrm{<mtext>450</mtext><mtext>SCC</mtext>}}$. Liposomal $\text{P}{}_{\mathrm{<mtext>450</mtext><mtext>SCC</mtext>}}$ required cholesterol for its optimum reduction with adrenodoxin, adrenodoxin reductase, and NADPH in the presence of CO. About 70% of the total heme in the dioleoylglycerophosphocholine liposomes was reduced by the enzymatic reduction in the presence of cholesterol, indicating that 70% of the total molecules are exposed to the surface of the outer monolayer. In order to see the location of the heme in membrane, the dioleoylglycerophosphocholine-liposomal $\text{P}{}_{\mathrm{<mtext>450</mtext><mtext>SCC</mtext>}}$ was subjected to $\text{p-}\text{chloromercuriphenyl sulfonic acid}$ treatment. This reagent destroyed the liposomal $\text{P}{}_{\mathrm{<mtext>450</mtext><mtext>SCC</mtext>}}$. These results suggest that the heme is located in the proximity of the $\text{p-}\text{chloromercuriphenyl sulfonic acid}$ reacting sites which are exposed to the surface, or located on the vincinity of polar heads of the membrane.     

Ligand-dependent reactivity of (Na+ + K+)-ATPase with showdomycin

Showdomycin inhibited pig brain ($\text{Na}{}^{\mathrm{+}}\text{+}\text{K}{}^{\mathrm{+}}\text{)-}\text{ATPase}$ with pseudo first-order kinetics. The rate of inhibition by showdomycin was examined in the presence of 16 combinations of four ligands, i.e., Na⁺, K⁺, Mg²⁺ and ATP, and was found to depend on the ligands added. Combinations of ligands were divided into five groups in terms of the magnitude of the rate constant; in the order of decreasing rate constants these were: (1)$\text{Na}{}^{\mathrm{+}}\text{+}\text{Mg}{}^{\mathrm{2+}}\text{+}\text{ATP}$, (2) $\text{Mg}{}^{\mathrm{2+}}$, $\text{Mg}{}^{\mathrm{2+}}\text{+}\text{K}{}^{\mathrm{+}}$, $\text{K}{}^{\mathrm{+}}$ and none, (3) $\text{Na}{}^{\mathrm{+}}\text{+}\text{Mg}{}^{\mathrm{2+}}\text{,}\text{Na}{}^{\mathrm{+}}$, $\text{K}{}^{\mathrm{+}}\text{+}\text{Na}{}^{\mathrm{+}}$ and $\text{Na}{}^{\mathrm{+}}\text{+}\text{K}{}^{\mathrm{+}}\text{+}\text{Mg}{}^{\mathrm{2+}}$, (4) $\text{Mg}{}^{\mathrm{2+}}\text{+}\text{K}{}^{\mathrm{+}}\text{+}\text{ATP}\text{,}\text{K}{}^{\mathrm{+}}\text{+}\text{ATP}$ and $\text{Mg}{}^{\mathrm{2+}}\text{+}\text{ATP}\text{, (5)}\text{K}{}^{\mathrm{+}}\text{+}\text{Na}{}^{\mathrm{+}}\text{+}\text{ATP}$, $\text{Na}{}^{\mathrm{+}}\text{+}\text{ATP}$, $\text{Na}{}^{\mathrm{+}}\text{+}\text{ATP}$, $\text{Na}{}^{\mathrm{+}}\text{+}\text{K}{}^{\mathrm{+}}\text{+}\text{Mg}{}^{\mathrm{2+}}\text{+}\text{ATP}$ and ATP. The highest rate was obtained in the presence of Na⁺, Mg²⁺ and ATP. The apparent concentrations of Na⁺, Mg²⁺ and ATP for half-maximum stimulation of inhibition ($\text{K}{}_{0.5}{}^{\mathrm{<mtext>s</mtext>}}$) were 3 mM, 0.13 mM and 4μM, respectively. The rate was unchanged upon further increase in Na⁺ concentration from 140 to 1000 mM. The rates of inhibition could be explained on the basis of the enzyme forms present, including E₁, E₂, ES, E₁-P and E₂-P, i.e., E₂ has higher reactivity with showdomycin than E₁, while E₂-P has almost the same reactivity as E₁-P. We conclude that the reaction of ($\text{Na}{}^{\mathrm{+}}\text{+}\text{K}{}^{\mathrm{+}}\text{)-}\text{ATPase}$ proceeds via at least four kinds of enzyme form (E₁, E₂, E₁ · nucleotide and EP), which all have different conformations.     

A/California/7/2009与A/California/4/2009病毒感染力比较

目的甲型H1N1流感病毒A/California/7/2009与A/California/4/2009病毒序列比较同源性在99%以上,本实验旨在比较两株病毒感染BALB/c小鼠研究感染力强弱。方法分别将A/California/7/2009（CA7）与A/California/4/2009（CA4）两株病毒分别连续10倍稀释后,对4~6周龄雌性BALB/c小鼠经乙醚麻醉后进行滴鼻攻毒,每个稀释度接种10只实验小鼠,测定CA7 MLD50为101.24/0.05 mL,检测小鼠感染、致病的多项指标,观察期为14 d。结果相同TCID50的CA7和CA4病毒感染小鼠,CA4感染小鼠后14 d内死亡率为20%,而CA7感染小鼠后8 d内死亡率为100%。CA7 106TCID50感染的小鼠病理表现为重度弥漫性间质性肺炎,CA4 106TCID50感染的小鼠病理表现为中度-重度间质性肺炎。结论在相同条件下,CA7感染力明显强于CA4。     

Characterization of partially purified (Na+ + K+)-ATPase from porcine lens

The partial purification of $\text{(}\text{Na}{}^{\mathrm{+}}\text{+}\text{K}{}^{\mathrm{+}}\text{)-}\text{ATPase}$ from pig lens has been achieved by treatment with deoxycholate followed by density gradient centrifugation. The specific activity of the final preparation, ranging from 300 to 500 nmol/h per mg protein, is increased approx. 100-fold compared to the homogenate. A parallel increase in $\text{p-}\text{nitrophenylphosphatase}$ activity is also observed. Sodium dodecyl sulfate (SDS) gel electrophoresis reveals six major protein bands, one of which is the 93 kDa α subunit of $\text{(}\text{Na}{}^{\mathrm{+}}\text{+}\text{K}{}^{\mathrm{+}}\text{)-}\text{ATPase}$ which can be phosphorylated by reaction with [γ-³²P]ATP. A second band contains a glycoprotein which displays an apparent molecular weight of 51 000 and thus appears to be the β subunit of the enzyme. The enzyme is sensitive to ouabain with the $\text{I}{}_{50}$ for $\text{(}\text{Na}{}^{\mathrm{+}}\text{+}\text{K}{}^{\mathrm{+}}\text{)-}\text{ATPase}$ and $\text{p-}\text{nitrophenylphosphatase}$ inhibition being 1.2 and 1.3 μM, respectively. Several agents which inhibit $\text{Na}{}^{\mathrm{+}}\text{+}\text{K}{}^{\mathrm{+}}\text{)-}\text{ATPase}$ from other tissues such as oligomycin, Ca²⁺, vanadate, $\text{N-}\text{ethylmaleimide}$, $\text{p-}\text{chloromercuribenzenesulfonic acid}$ (PCMBS) and 5,5′-dithiobis-(2-nitrobenzoic acid) (DTNB) also inhibit the lens enzyme. Monovalent cations other than K⁺ are partially effective in activating the ($\text{Na}{}^{\mathrm{+}}\text{+}\text{K}{}^{\mathrm{+}}$)-ATPase and $\text{p-}\text{nitrophenylphosphatase}$ activities. The K⁺ congeners were relatively more effective in supporting $\text{(}\text{Na}{}^{\mathrm{+}}\text{+}\text{K}{}^{\mathrm{+}}\text{)-}\text{ATPase}$ compared to $\text{p-}\text{nitrophenylphosphatase}$ activity. Other kinetic properties of the lens enzyme are also comparable to those of the enzyme from other tissues. Utilizing the partially purified membrane bound enzyme, discontinuities in Arrhenius plots of $\text{(}\text{Na}{}^{\mathrm{+}}\text{+}\text{K}{}^{\mathrm{+}}\text{)-}\text{ATPase}$ activity, $\text{p-}\text{nitrophenylphosphatase}$ activity and fluoresence polarization of the fluidity probe, 1,6-diphenyl-1,3,5-hexatriene (DPH), are observed near the physiological temperature of lens. The possible significance of these observations for the mechanism of cataract formation are discussed.     

An electron spin probe study of (Na+ + K+)-ATPase-Containing membranes

The modulating effect of membrane lipids on enzyme function has been described by several investigators. We have used the spin probe $\text{N-}\text{oxyl}\text{-4′,4′-}\text{dimethyloxazolidine}\text{-12-}\text{keto}$ methyl stearate (M 12-NSE) to study this interaction in ox brain membranes enriched with $\text{(}\text{Na}{}^{\mathrm{+}}\text{+}\text{K}{}^{\mathrm{+}}\text{)-}\text{ATPase}$. This methyl ester of stearic acid is practically insoluble in aqueous media, and consequently spectra of M 12-NSE-labelled preparations are free of “liquid lines”.At least two types of spectra may be obtained when ox brain microsomes are spin labelled with M 12-NSE, indicating the presence of two distinct binding sites. At one site the spin label is relatively unrestricted and gives rise to an isotropic spectrum. A second spectrum, which is obtained from spin label at another site, is similar to that which is observed after incorporation of M 12-NSE into phospholipid bilayers. This suggests that this latter site is within the core of the microsomal membrane.The two binding sites differ in their affinity for the spin probe. The low affinity site is both more abundant in crude preparations and is more easily removed by detergent treatment; spin labels at this site produce isotropic spectra. The high affinity sites are fewer in number and produce broad spectra. In addition these high affinity sites increase in concentration as the enzyme undergoes purification.The two sites are quite distinct in their sensitivity to ascorbic acid, the low affinity site showing a considerably greater rate of reduction by this agent.This study also demonstrates that the delipidation effects of sodium dodecyl sulfate and sodium deoxycholate on $\text{(}\text{Na}{}^{\mathrm{+}}\text{+}\text{K}{}^{\mathrm{+}}\text{)-}\text{ATPase-enriched}$ microsomes from ox brain are not identical.It is suggested that the two spin probe binding sites represent two different lipid domains, one of which is very closely associated with the $\text{(}\text{Na}{}^{\mathrm{+}}\text{+}\text{K}{}^{\mathrm{+}}\text{)-}\text{ATPase}$ enzyme and may reflect a protein-directed phospholipid specificity for this enzyme.     

Annular and non-annular binding sites on the (Ca2+ + Mg2+)-ATPase

Quenching of the fluorescence of the $\text{(}\text{Ca}{}^{\mathrm{2+}}\text{+}\text{Mg}{}^{\mathrm{2+}}\text{)-}\text{ATPase}$ purified from muscle sarcoplasmic reticulum can be used to measure relative binding constants of hydrophobic compounds to the phospholipid-protein interface. We show that the binding constant for cholesterol is considerably less than that for phosphatidylcholine, so that cholesterol is effectively excluded from the phospholipid annulus around the ATPase. However, dibromocholestan-3β-ol causes quenching of the fluorescence of the ATPase, and so has access to other, non-annular sites. We suggest that these non-annular sites could be at protein/protein interfaces in ATPase oligomers. Oleic acid can bind at the phospholipid/protein interface, although its binding constant is less than that for a phosphatidylcholine, and it can also bind at the postulated non-annular sites. The effects of these compounds on the activity of the ATPase depend on the structure of the phospholipid present in the systems.     

Comparison of parameters estimated from A/Ci and A/Cc curve analysis

The parameters estimated from traditional A/C _i curve analysis are dependent upon some underlying assumptions that substomatal CO₂ concentration (C _i) equals the chloroplast CO₂ concentration (C _c) and the C _i value at which the A/C _i curve switches between Rubisco- and electron transport-limited portions of the curve (C _i-t) is set to a constant. However, the assumptions reduced the accuracy of parameter estimation significantly without taking the influence of C _i-t value and mesophyll conductance (g _m) on parameters into account. Based on the analysis of Larix gmelinii’s A/C _i curves, it showed the C _i-t value varied significantly, ranging from 24 Pa to 72 Pa and averaging 38 Pa. t-test demonstrated there were significant differences in parameters respectively estimated from A/C _i and A/C _c curve analysis (p<0.01). Compared with the maximum ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) carboxylation rate (V_cmax), the maximum electron transport rate (J_max) and J_max/V_cmax estimated from A/C _c curve analysis which considers the effects of g _m limit and simultaneously fits parameters with the whole A/C _c curve, mean V_cmax estimated from A/C _i curve analysis (V_cmax-C _i) was underestimated by 37.49%; mean Jmax estimated from A/C _i curve analysis (J_max-C _i) was overestimated by 17.8% and (J_max-C _i)/(V_cmax-C _i) was overestimated by 24.2%. However, there was a significant linear relationship between V_cmax estimated from A/C _i curve analysis and V_cmax estimated from A/C _c curve analysis, so was it J_max (p<0.05).     

Regulation of rat brain (Na+ + K+)-ATPase activity by cyclic AMP

The interaction between the $\text{(}\text{Na}{}^{\mathrm{+}}\text{+}\text{K}{}^{\mathrm{+}}\text{)-}\text{ATPase}$ and the adenylate cyclase enzyme systems was examined. Cyclic AMP, but not 5′-AMP, cyclic GMP or 5′-GMP, could inhibit the $\text{(}\text{Na}{}^{\mathrm{+}}\text{+}\text{K}{}^{\mathrm{+}}\text{)-}\text{ATPase}$ enzyme present in crude rat brain plasma membranes. On the other hand, the cyclic AMP inhibition could not be observed with purified preparations of $\text{(}\text{Na}{}^{\mathrm{+}}\text{+}\text{K}{}^{\mathrm{+}}\text{)-}\text{ATPase}$ enzyme. Rat brain synaptosomal membranes were prepared and treated with either NaCl or cyclic AMP plus NaCl as described by Corbin, J., Sugden, P., Lincoln, T. and Keely, S. ((1977) J. Biol. Chem. 252, 3854–3861). This resulted in the dissociation and removal of the catalytic subunit of a membrane-bound cyclic AMP-dependent protein kinase. The decrease in cyclic AMP-dependent protein kinase activity was accompanied by an increase in $\text{(}\text{Na}{}^{\mathrm{+}}\text{+}\text{K}{}^{\mathrm{+}}\text{)-}\text{ATPase}$ activity. Exposure of synaptosomal membranes containing the cyclic AMP-dependent protein kinase holoenzyme to a specific cyclic AMP-dependent protein kinase inhibitor resulted in an increase in $\text{(}\text{Na}{}^{\mathrm{+}}\text{+}\text{K}{}^{\mathrm{+}}\text{)-}\text{ATPase}$ enzyme activity. Synaptosomal membranes lacking the catalytic subunit of the cyclic-AMP-dependent protein kinase did not show this effect. Reconstitution of the solubilized membrane-bound cyclic AMP-dependent protein kinase, in the presence of a neuronal membrane substrate protein for the activated protein kinase, with a purified preparation of $\text{(}\text{Na}{}^{\mathrm{+}}\text{+}\text{K}{}^{\mathrm{+}}\text{)-}\text{ATPase}$, resulted in a decrease in overall $\text{(}\text{Na}{}^{\mathrm{+}}\text{+}\text{K}{}^{\mathrm{+}}\text{)-}\text{ATPase}$ activity in the presence of cyclic AMP. Reconstitution of the protein kinase alone or the substrate protein alone, with the $\text{(}\text{Na}{}^{\mathrm{+}}\text{+}\text{K}{}^{\mathrm{+}}\text{)-}\text{ATPase}$ has no effect on $\text{(}\text{Na}{}^{\mathrm{+}}\text{+}\text{K}{}^{\mathrm{+}}\text{)-}\text{ATPase}$ activity in the absence or presence of cyclic AMP. Preliminary experiments indicate that, when the activated protein kinase and the substrate protein were reconstituted with the $\text{(}\text{Na}{}^{\mathrm{+}}\text{+}\text{K}{}^{\mathrm{+}}\text{)-}\text{ATPase}$ enzyme, there appeared to be a decrease in the Na⁺-dependent phosphorylation of the Na⁺-ATPase enzyme, while the K⁺-dependent dephosphorylation of the $\text{(}\text{Na}{}^{\mathrm{+}}\text{+}\text{K}{}^{\mathrm{+}}\text{)-}\text{ATPase}$ was unaffected.