Comparison of drug susceptibility between Escherichia coli detected in stool cultures of patients undergoing transrectal prostate needle biopsy and Escherichia coli in hospital-wide urine antibiograms

A prostate biopsy is essential for prostate cancer diagnosis. However, infections are one of the biopsy-associated complications, and post-biopsy fever is estimated to occur in approximately 1% of all cases. It may thus be beneficial to perform a rectal swab culture before a transrectal prostate biopsy to confirm the presence of resistant bacteria and select preventive antibacterial agents according to the drug susceptibility results. This study aimed to determine whether there is a difference between the drug susceptibility of bacteria detected in the stool of patients who were scheduled to undergo prostate biopsy and the hospital-wide urine antibiogram. Patients suspected of having prostate cancer who underwent transrectal prostate biopsy via transrectal ultrasonography between August 1, 2016, and June 30, 2020, were included in this study. Stool samples were collected and cultured before biopsy. Overall, 99 patients underwent prostate biopsy, and of these, culture results were available for 81 patients (81.8%). Escherichia coli was detected in 74.0% (60 samples) of the stool culture samples, of which 4 samples were extended-spectrum β-lactamase-producing types. We found greater susceptibility of Escherichia coli to ampicillin, fluoroquinolones, sulfamethoxazole/trimethoprim, and cefixime in the stool culture antibiogram than in the hospital-wide urine antibiogram. We also found a significantly low incidence of ESBL-positive Escherichia coli in the stool culture antibiogram with p-values of 0.009, 0.007, and 0.03 compared to the hospital-wide urine antibiograms for 2017, 2018, and 2019, respectively. Stool culture of prostate cancer patients undergoing biopsy may provide useful information for selecting prophylactic antimicrobial agents.     

Effect of sodium mercaptoacetic acid on different antimicrobial disks in the sodium mercaptoacetic acid double disk synergy test for detection of IMP-1 metallo-β-lactamase-producing Pseudomonas aeruginosa isolates in Japan

We determined the optimal antimicrobial in the sodium mercaptoacetic acid double disk synergy test (SMA-DDST) for the detection of IMP-1-producing Pseudomonas aeruginosa isolates in Japan and evaluated the performance of the test.Fifty-four P. aeruginosa clinical isolates were tested, including 39 IMP-1 producers and 15 non-metallo-β-lactamase (MBL)-producing carbapenem- and ceftazidime (CAZ)-resistant isolates. The SMA-DDST was performed with CAZ, cefepime (CFPM), imipenem (IPM), meropenem (MEPM), doripenem (DRPM), or biapenem (BIPM)-containing disks. The sensitivity of the SMA-DDST with CAZ, CFPM, IPM, MEPM, DRPM, and BIPM was 39/39 (100%), 36/39 (92%), 18/39 (46%), 8/39 (21%), 19/39 (49%), and 36/39 (92%), respectively. The specificity was 15/15 (100%) for all SMA-DDSTs. This suggests that the isolates may have a resistance mechanism other than MBL production for IPM, MEPM, or DRPM. Since the CAZ resistance mechanism in P. aeruginosa is the same as that of CFPM, but differs from that of carbapenems, we conclude that combining CAZ with BIPM SMA-DDSTs can prevent any failure in the detection of IMP-1-producing P. aeruginosa.     

头孢他啶/阿维巴坦对耐碳青霉烯肠杆菌科细菌的体外抗菌活性研究

目的 头孢他啶/阿维巴坦(CAZ/AVI)是第三代头孢菌素和新型的非β-内酰胺酶类的β-内酰胺酶抑制剂阿维巴坦相 结合的抗生素,对多重耐药菌具有抗菌活性,本研究评价CAZ/AVI对临床分离耐碳青霉烯肠杆菌科细菌(carbapenem-resistant Enterobacteriaceae,CRE)的体外抗菌活性,同时评价CAZ/AVI对不同菌属的CRE菌和携带不同耐药基因型的CRE菌的体外抗菌 活性。方法 对收集来自解放军302医院和宁夏医科大学总医院2008年1月至2017年12月临床分离的266株CRE菌株进行了最低抑 菌浓度(minimum bacteriostatic concentration, MIC)的测定;采用特异引物扩增法进行耐药基因型的测定,进一步分析CAZ/AVI对 携带不同耐药基因型的CRE菌的体外抗菌活性。结果 CAZ/AVI体对临床分离CRE菌的体外抑菌活性为49.62%,明显优于头孢 他啶和其他对照药物(P=0),但弱于多黏菌素B和替加环素(P=0.003);对克雷伯菌属CRE菌的体外抑菌效果明显,可达到63.75% 的体外活性抑菌率,其次为肠杆菌属CRE菌(23.81%),对埃希菌属CRE菌的体外抑菌率最低(13.33%);对于携带blaKPC-2 基因型 的CRE菌株体外抑菌率可达到69.23%,而对于携带blaNDM 和blaIMP 的基因型的CRE菌株作用相当(P=0.889),体外抑菌率分别为 2.22%和8.33%。结论 CAZ/AVI坦对CRE菌表现出了一定的体外抗菌活性优势,尤其是增强了头孢他啶的体外抗菌活性。对克 雷伯菌属CRE菌的体外抑菌活性明显,并且能够很好的抑制携带blaKPC-2 基因型的CRE菌。     

头孢哌酮/舒巴坦、亚胺培南/西司他丁与头孢他啶治疗老年人肺部感染的疗效对比分析

比较头孢哌酮／舒巴坦（ＣＰＺ／ＳＢ）、亚胺培南／西司他丁（ＩＰＭ／ＣＳ）与头孢他啶（ＣＡＺ）治疗老年人肺部感染的疗效及其安全性。共入选老年肺部感染患者１０４例,可供评价疗效者９２例,其中应用ＣＰＺ／ＳＢ３０例、ＩＰＭ／ＣＳ３０例、ＣＡＺ３２例;１２例病例因应用时间不足３ｄ或因在治疗过程中加用其他抗菌药物而未被列入评价分析。ＣＰＺ／ＳＢ、ＣＡＺ每次１ｇ,每日３次,疗程４～１４ｄ;ＩＰＭ／ＣＳ每次０．     

The presynaptic CaV2.2 channel-transmitter release site core complex

CaV2.2 channels play a key role in the gating of transmitter release sites (TRS) at presynaptic terminals. Physiological studies predict that the channels are linked directly to the TRS but the molecular composition of this complex remains poorly understood. We have used a high-affinity anti-CaV2.2 antibody, Ab571, to test a range of proteins known to contribute to TRS function for both an association in situ and a link in vitro. CaV2.2 clusters were isolated intact on immunoprecipitation beads and coprecipitated with a number of these proteins. Quantitative staining covariance analysis (ICA/ICQ method) was applied to the transmitter release face of the giant calyx terminal in the chick ciliary ganglion to test for TRS proteins with staining intensities that covary in situ with CaV2.2, resulting in a covariance sequence of NSF>RIM>spectrin>Munc18>VAMP>alpha-catenin, CASK>SV2>Na+-K+ approximately 0. A high-NaCl dissociation challenge applied to the immunoprecipitated complex, using the fractional recovery (FR) method [Khanna, R., Li, Q. & Stanley, E.F. (2006) PLoS.ONE., 1, e67], was used to test which proteins were most intimately associated with the channel, generating an FR sequence for CaV2.2 of: VAMP>or=actin>tubulin, NSF, Munc18, syntaxin 1>spectrin>CASK, SNAP25>RIM, Na+-K+ pump, v-ATPase, beta-catenin approximately 0. Proteins associated with endocytosis are considered in a companion paper [Khanna et al. (2007)Eur. J. Neurosci., 26, 560-574]. With the exception of VAMP and RIM, the ICQ and FR sequences were consistent, suggesting that proteins that covary the most strongly with CaV2.2 in situ are also the most intimately attached. Our findings suggest that the CaV2.2 cluster is an integral element of a multimolecular vesicle-fusion module that forms the core of a multifunctional TRS.     

Differential expression of active zone proteins in neuromuscular junctions suggests functional diversification

Nerve terminals of the central nervous system (CNS) contain specialized release sites for synaptic vesicles, referred to as active zones. They are characterized by electron-dense structures that are tightly associated with the presynaptic plasma membrane and organize vesicle docking and priming sites. Recently, major protein constituents of active zones have been identified, including the proteins Piccolo, Bassoon, RIM, Munc13, ERCs/ELKs/CASTs and liprins. While it is becoming apparent that each of these proteins is essential for synaptic function in the CNS, it is not known to what extent these proteins are involved in synaptic function of the peripheral nervous system. Somatic neuromuscular junctions contain morphologically and functionally defined active zones with similarities to CNS synapses. In contrast, sympathetic neuromuscular varicosities lack active zone-like morphological specializations. Using immunocytochemistry at the light and electron microscopic level we have now performed a systematic investigation of all five major classes of active zone proteins in peripheral neuromuscular junctions. Our results show that somatic neuromuscular endplates contain a full complement of all active zone proteins. In contrast, varicosities of the vas deferens contain a subset of active zone proteins including Bassoon and ELKS2, with the other four components being absent. We conclude that Bassoon and ELKS2 perform independent and specialized functions in synaptic transmission of autonomic synapses.     

产ESBLs肺炎克雷伯菌的致病性及头孢他啶疗效分析

目的 探讨产ESBLs肺炎克雷伯菌不同感染途径的致病性差异及头孢他啶对产ESBLs肺炎克雷伯菌腹腔感染小鼠的保护作用.方法 分别采用滴鼻途径建立小鼠呼吸道感染模型和腹腔注射途径建立小鼠腹腔感染模型,将小鼠分成6组,检测产ESBLs肺炎克雷伯菌对小鼠的半数致死量.另将头孢他啶体外药敏试验敏感的产ESBLs肺炎克雷伯菌腹腔感染小鼠分成3组,采用不同治疗方法考察头孢他啶的体内治疗作用,同时与亚胺培南/西司他丁钠疗效做对比分析.结果 产ESBLs肺炎克雷伯菌经过滴鼻途径感染小鼠未见死亡,经腹腔感染途径的半数致死量为105;头孢他啶预防给药组小鼠的死亡率为10%,同时给药与感染4h后给药组小鼠的死亡率为30%,头孢他啶对产ESBLs肺炎克雷伯菌腹腔感染小鼠的保护作用与亚胺培南/西司他丁钠作用一致.结论 产ESBLs肺炎克雷伯菌经呼吸道感染途径的致病性比腹腔感染途径弱,头孢他啶体外药敏试验敏感的产ESBLs肺炎克雷伯菌感染可以采用头孢他啶治疗,但应尽早使用.     

Active zone protein CAST is a component of conventional and ribbon synapses in mouse retina

CAST is a novel cytomatrix at the active zone (CAZ)-associated protein. In conventional brain synapses, CAST forms a large molecular complex with other CAZ proteins, including RIM, Munc13-1, Bassoon, and Piccolo. Here we investigated the distribution of CAST and its structurally related protein, ELKS, in mouse retina. Immunofluorescence analyses revealed that CAST and ELKS showed punctate signals in the outer and inner plexiform layers of the retina that were well-colocalized with those of Bassoon and RIM. Both proteins were found presynaptically at glutamatergic ribbon synapses, and at conventional GABAergic and glycinergic synapses. Moreover, immunoelectron microscopy revealed that CAST, like Bassoon and RIM, localized at the base of synaptic ribbons, whereas ELKS localized around the ribbons. Both proteins also localized in the vicinity of the presynaptic plasma membrane of conventional synapses in the retina. These results indicated that CAST and ELKS were novel components of the presynaptic apparatus of mouse retina.     

Differential distribution of release-related proteins in the hippocampal CA3 area as revealed by freeze-fracture replica labeling

Synaptic vesicle release occurs at a specialized membrane domain known as the presynaptic active zone (AZ). Several membrane proteins are involved in the vesicle release processes such as docking, priming, and exocytotic fusion. Cytomatrix at the active zone (CAZ) proteins are structural components of the AZ and are highly concentrated in it. Localization of other release-related proteins including target soluble N-ethylmaleimide-sensitive-factor attachment protein receptor (t-SNARE) proteins, however, has not been well demonstrated in the AZ. Here, we used sodium dodecyl sulfate-digested freeze-fracture replica labeling (SDS-FRL) to analyze quantitatively the distribution of CAZ and t-SNARE proteins in the hippocampal CA3 area. The AZ in replicated membrane was identified by immunolabeling for CAZ proteins (CAZ-associated structural protein [CAST] and Bassoon). Clusters of immunogold particles for these proteins were found on the P-face of presynaptic terminals of the mossy fiber and associational/commissural (A/C) fiber. Co-labeling with CAST revealed distribution of the t-SNARE proteins syntaxin and synaptosomal-associated protein of 25 kDa (SNAP-25) in the AZ as well as in the extrasynaptic membrane surrounding the AZ (SZ). Quantitative analysis demonstrated that the density of immunoparticles for CAST in the AZ was more than 100 times higher than in the SZ, whereas that for syntaxin and SNAP-25 was not significantly different between the AZ and SZ in both the A/C and mossy fiber terminals. These results support the involvement of the t-SNARE proteins in exocytotic fusion in the AZ and the role of CAST in specialization of the membrane domain for the AZ.