老年感染性疾病患者中肠杆菌科细菌产AmpC β-内酰胺酶菌株的临床分析

目的 了解产AmpC酶肠杆菌科细菌在老年感染性疾病患者中的感染情况，指导临床合理使用抗生素。方法 对233份老年患者的各类标本中分离出的肠杆菌科细菌进行分析鉴定，采用酶提取物三维试验检测产AmpC酶菌株，纸片扩散法测定产AmpC酶菌株对12种常用抗菌药物的敏感性。结果 检出产AmpC酶菌株20例，总检出率为8．6％，以阴沟肠杆菌检出率最高，达到35．1％(13／37)。产AmpC酶菌株对亚安培南、头孢吡肟较为敏感，其中对亚安培南的敏感率为100％；对第3代头孢菌素类抗生素及氨曲南有较高耐药性，耐药率在85％～100％之间。结论 产AmpC酶菌株对常用抗菌药物的耐药性已相当严重，应重视产AmpC酶细菌的监测与控制。     

三维法测定耐头孢美唑菌β-内酰胺酶的研究

目的检测耐头孢美唑的肠杆菌科细菌持续高产AmpC酶和超广谱β-内酰胺酶(ESBLs)及对其他抗生素的耐药状况。方法采用三维法测定AmpC和ESBLs及纸片扩散法测定16种抗菌药物的抑菌环直径。结果50株耐头孢美唑的肠杆菌科菌有24．0％的菌株同时产AmpC酶和ESBLs,有28．0％的菌株单产AmpC酶,有6．0％的菌株单产ESBLs,有46、0％的菌株AmpC酶和ESBLs酶均阴性;AmpC和ESBLs总的阳性率分别为48．0％和26．0％;AmpC和ESBLs总的阳性率分别为44．0％和26．0％;肠杆菌属的产AmpC酶率最高,不动杆菌属、铜绿假单胞菌、弗氏柠檬酸杆菌、气单胞菌属均能产生AmpC酶,而大肠埃希菌产AmpC酶的几率较小。结论耐头孢美唑的肠杆菌科细菌产AmpC酶几率较高,应加强监测。     

大肠埃希菌和肺炎克雷伯菌中质粒AmpCβ内酰胺酶基因型的检测

目的了解产质粒介导的AmpC酶大肠埃希菌和肺炎克雷伯菌的耐药性和基因型。方法收集2002年1月至2004年5月间呼吸科临床标本中分离的大肠埃希菌和肺炎克雷伯菌共110株，用酶提取物三维试验检测AmpC酶；用等电聚焦电泳、耐药质粒电转化试验、聚合酶链反应（PCR）及测序确定AmpC酶基因型。结果大肠埃希菌和肺炎克雷伯菌中AmpC酶检出率分别为9．30％（4／43），4．48％（3／67）。药敏试验结果显示产酶株对头孢西丁全部耐药，对第三代头孢菌素、酶抑制剂、氨曲南、阿米卡星及环丙沙星均有不同程度耐药，对头孢吡肟及亚胺培南较敏感。7株产AmpC酶菌株中有5株通过电转化试验可将头孢西丁耐药性传递给受体菌，经PCR扩增和测序证实为质粒介导DHA-1型AmpC酶。结论临床分离的大肠埃希菌和肺炎克雷伯菌中已经出现产质粒介导AmpC酶菌株，其耐药性能够水平传播，给临床抗感染治疗带来重大威胁。     

老年患者医院感染前五位常见革兰阴性杆菌ESBLs和AmpCβ-内酰胺酶分析

目的了解华东医院老年患者前5位常见革兰阴性杆菌产酶类型,为指导临床合理选用抗菌药物提供依据。方法收集2011年9月-2012年8月分离自老年医院感染患者的前5位常见的耐头孢西丁的革兰阴性杆菌,用改良的三维试验检测并分析革兰阴性杆菌的产酶类型。结果前5位常见的革兰阴性杆菌分别为鲍曼不动杆菌（88株）、铜绿假单胞菌（61株）、阴沟肠杆菌（42株）、产气肠杆菌（21株）和肺炎克雷伯菌（15株）,共计227个菌株;AmpCβ-内酰胺酶（简称AmpC酶）阳性率9．25％（21株）,ESBLs阳性率14．10％（32株）,同时产AmpC酶和ESBLs酶（简称SSBLs）的阳性率12．78％（29株）,其他水解酶阳性率28．19％（64株）。结论老年医院感染患者前5位常见细菌的产酶率高,耐药现象严重,应加强耐药性监测和控制。     

可疑产碳青霉烯酶肠杆菌的耐药性及与β-内酰胺酶的关系

目的观察本地区可疑产碳青霉烯酶肠杆菌的耐药性及与B．内酰胺酶的关系。方法采用VITEK-2全自动细菌鉴定仪检测55株可疑产碳青霉烯酶肠杆菌对21种抗生素的药敏情况,以改良Hodge试验进行碳青霉烯酶筛选,以纸片扩散初筛试验、扩散确证试验进行超广谱B-内酰胺酶（ESBLs）表型检查,以头孢西丁三维试验进行头孢菌毒酶（AmpC酶）p-内酰胺酶表型检查,PCR法检测β-内酰胺酶基因表达并进行产物测序。结果55株菌株对青霉素类、头孢菌素类抗生素耐药率高达87％以上,对亚胺培南、美洛培南、丁胺卡那霉素耐药率在30％以下;β-内酰胺酶表型阳性率为74．54％,主要来自产ESBLs＋AmpC酶菌株,其次为单产ESBLs酶和单产AmpC酶菌株;肺炎克雷伯菌碳青霉烯酶、DHA、CIT、TEM、CTX．M型β-内酰胺酶基因阳性率分别为7．27％、16．36％、27．27％、27．27％、16．36％。结论本地区耐碳青霉烯类抗生素的菌株呈不断增加趋势,目前尚缺乏有效治疗产酶细菌所致感染的方法;菌株耐碳青霉烯类药物的主要原因并非产碳青霉烯酶,而可能为同时产ESBLs＋AmpC酶或存在其他耐药机制。     

产气肠杆菌连续分离株的耐药性及β-内酰胺类抗生素耐药机制的研究

目的 探讨临床连续分离的产气肠杆菌耐药性及耐碳青霉烯类药物菌株对β-内酰胺类药物耐药的主要机制。方法 用Vitek2-Compact仪对临床连续分离的240株产气肠杆菌进行鉴定和常规药敏试验,并筛选出耐碳青霉烯类药物的菌株;用琼脂稀释法测定其对碳青霉烯类药物的MIC值;用改良的三维试验方法分别检测耐药菌株的ESBLs与AmpC酶;改良Hodge试验法检测碳青霉烯酶;用PCR扩增法检测3种β-内酰胺酶的耐药基因;结果 240株产气肠杆菌对23种常用抗生素的耐药率在3.8%～100%之间,最高为头孢西丁(100%)、最低为亚胺培南(3.8%);筛选出10株耐碳青霉烯类产气肠杆菌;三维试验10株菌ESBLs 及AmpC酶均为阳性,Hodge试验阳性7株。PCR结果示,携带blaKPC基因7株;携带blaCTX-M基因7株,携带blaSHV基因2株;携带blaDHA基因6株,携带blaACT/MIR型ampC基因4株; 16SrRNA基因定量确定ampC基因的表达增加的3株。结论 产气肠杆菌对临床常用抗菌药物具有较高的耐药性,其主要耐药机制为产碳青霉烯酶、ESBLs与AmpC酶。     

革兰阴性杆菌产AmpC酶及超广谱β-内酰胺酶的研究

为探讨临床分离的对第三代头孢菌素耐药的革兰阴性杆菌AmpCβ－内酰胺酶（AmpC)和超广谱β－内酰胺酶（ESBLs)的分布情况，采用头孢西丁三维试验检测AmpC酶，纸片确证试验和头孢曲松三维试验检测ESBLs。结果显示，227株革兰阴性杆菌中产AmpC酶者97株（占42．6％），产ESBLs者38株（占16．7％）。提示AmpC酶和ESBLs是导致革兰阴性杆菌耐药的两类主要酶。AmpC酶和ESBLs的单克隆抗体有望为这类细菌感染的免疫生物治疗提供新方法。     

耐多药大肠埃希菌AmpC酶基因型及耐药性

目的探讨临床分离耐多药大肠埃希菌(E.coli)产AmpCβ-内酰胺酶(AmpC酶)现状。方法初筛试验及三维试验:检测产AmpC酶菌株;纸片扩散法(K-B法):测定临床分离71株大肠埃希菌对头孢噻肟(CTX)等10种抗菌药物的抗菌活性;PCR技术检测三维实验阳性菌株的AmpC酶基因。阳性扩增片段送上海生工生物技术公司进行基因测序。结果在71株大肠埃希菌中粗筛阳性产AmpC酶菌株共11株,通过头孢西丁三维试验分离出产AmpC酶的菌株8株,占总菌株数11.27%。药敏结果显示对亚胺培南全敏感,对阿米卡星等9种抗菌药物均有不同程度耐药;耐药模式中以耐多药菌株24株(33.80%);产AmpC酶菌株对多种常用抗生素的耐药率明显高于非产AmpC酶菌株(P<0.05);检测发现2株质粒AmpC酶基因阳性。结论大肠埃希菌的多重耐药的现象突出;产AmpC酶菌株的耐药率明显高于非产AmpC酶菌株;质粒介导的AmpC酶的基因型表现为DHA-1。     

耐头孢西丁革兰阴性杆菌高产AmpC酶发生率及其基因型和耐药性

目的了解耐头孢西丁革兰阴性杆菌高产AmpC酶发生率及其基因型分布和耐药性状况。方法收集2004年9月-2005年3月分离自南京军区福州总院、福建省立医院、解放军476医院、福州?第二医院住院患者155株耐头孢西丁无重复革兰阴性杆菌,采用酶提取物三维试验检测AmpC酶;API药敏试验板和K-B法测定高产AmpC酶菌株对抗菌药物的敏感性;质粒转化试验定位耐药基因;PCR通用引物扩增AmpC酶与ESBLs基因及其序列测定,确定其基因亚型。结果在155株菌中有36株高产AmpC酶,高产AmpC酶发生率23.2%,分布在13种菌种中,其中大肠埃希菌、肺炎克雷伯菌、鲍氏不动杆菌和阴沟肠杆菌的发生率,分别为29.3%、13.9%、6/10、2/6。在36株高产AmpC酶菌株中检测出DHA-1型2株(肺炎克雷伯菌)、CMY-2型4株(大肠埃希菌),新发现基因CMY-22型1株(大肠埃希菌,GenBank登录号:DQ256079),5株携带CMY基因的大肠埃希菌分别同时带有TEM-1型广谱酶,TEM-144(新发现基因,GenBank登录号:DQ256080)、CTX-M-27、和CTX-M-14超广谱β-内酰胺酶。高产AmpC酶菌株耐药性严重,且呈多重耐药,但对亚胺培南和美罗培南的敏感率>87%。结论耐头孢西丁革兰阴性杆菌高产AmpC酶发生率较高,菌种分布较宽,耐药性强,治疗相关菌造成的感染应以亚胺培南和美罗培南为首选药物。福州地区临床分离株发现产DHA-1型AmpC酶肺炎克雷伯菌、产CMY-2型和CMY-22型AmpC酶大肠埃希菌。CMY-2型和CTX-M-27型为中国大陆首次报告,CMY-22型和TEM-144型为国内外首次发现。     

老年慢性阻塞性肺疾病患者产AmpC β-内酰胺酶阴沟肠杆菌基因型及用药策略初步探讨

阴沟肠杆菌对广谱头孢菌素的严重耐药性一直是临床关注的问题,其主要耐药机制之一就是产生持续高产型AmpC β-内酰胺酶(简称AmpC酶)[1],尤其是质粒介导的AmpC酶,具有可在不同菌属细菌之间水平传播的特点,易导致医院内感染的暴发流行[2].因此检测、分析阴沟肠杆菌AmpC酶的基因型别株对于研究和了解阴沟肠杆菌的耐药机制、指导临床合理用药,及时有效地控制产酶菌株引起的感染,有重要的实用价值.     

The immunoneuroendocrine role of melatonin

Abstract: A tight, physiological link between the pineal gland and the immune system is emerging from a series of experimental studies. This link might reflect the evolutionary connection between self-recognition and reproduction. Pinealectomy or other experimental methods which inhibit melatonin synthesis and secretion induce a state of immunodepression which is counteracted by melatonin. In general, melatonin seems to have an immunoenhancing effect that is particularly apparent in immunodepressive states. The negative effect of acute stress or immunosuppressive pharmacological treatments on various immune parameters are counteracted by melatonin. It seems important to note that one of the main targets of melatonin is the thymus, i.e., the central organ of the immune system. The clinical use of melatonin as an immunotherapeutic agent seems promising in primary and secondary immunodeficiencies as well as in cancer immunotherapy. The immunoenhancing action of melatonin seems to be mediated by T-helper cell-derived opioid peptides as well as by lymphokines and, perhaps, by pituitary hormones. Melatonin-induced-immuno-opioids (MHO) and lymphokines imply the presence of specific binding sites or melatonin receptors on cells of the immune system. On the other hand, lymphokines such as -γ-interferon and interleukin-2 as well as thymic hormones can modulate the synthesis of melatonin in the pineal gland. The pineal gland might thus be viewed as the crux of a sophisticated immunoneuroendocrine network which functions as an unconscious, diffuse sensory organ.     

Changes in connexin43, the gap junction protein of astrocytes, during development of the rat pineal gland

Abstract: The abundance of gap junctions between rat pineal astrocytes formed by connexin43 (Cx43) was studied during development. Levels and distribution of Cx43 were measured by immunoblotting and indirect immunofluorescence, respectively. The amount of Cx43 in cells located within the gland was low until about the 7th postnatal day and increased to adult values between the 14th and 21st days postpartum. Although astrocytes, recognized by their vimentin immunoreactivity, were scarce before birth, they were abundant by the 7th postnatal day suggesting that the low levels of Cx43 found at this age corresponded to a low expression of this protein. Localization of the immunoreactivity to Cx43 and vimentin showed a close correlation, indicating that mature or immature pineal astrocytes form gap junctions made of Cx43. Since Cx43 levels attained their adult values at about the time the innervation and the functional state of the gland reached maturity (2–3 weeks after birth), it is proposed that astrocyte gap junctions are involved in the function of the adult rat pineal gland.     

Response of rat pineal melatonin to calcium, magnesium, and lithium is circadian stage dependent

Abstract: Herein we documented the response of pineal melatonin production to electrolytes known to be effective on pineal function in view of a possible circadian stage dependence. We studied the release of melatonin by perifused rat pineal glands at 2 different circadian stages corresponding to the middle of the light and dark periods, i.e., respectively, 7 and 19 HALO (Hours After Light Onset, L:D = 12:12). The initial efflux rates were, as expected, much higher in the perifusates of glands removed from rats sacrificed during the dark phase than of those removed during the light phase. After 3 hr of perifusion, melatonin release reached similar levels which were found constant up to the 8th hr of perifusion, whatever the circadian stage. Perifusion of the glands with physiological concentrations for the rat of calcium (5.2 mmol/1) and magnesium (1.34 mmol/1) resulted in a stimulatory effect on the pineal glands removed from rats sacrificed in the middle of the dark period (19 HALO), whereas no effects were observed on the pineal glands removed from rats sacrificed during the light (7 HALO). Lithium (0.28 and 0.55 mmol/1) was ineffective on melatonin release in pineal glands removed 7 and 19 HALO. Our results show differences in the initial efflux rates of melatonin and in the response of perifused pineal glands to calcium and magnesium according to the circadian stage.     

Conservative management of perforated duodenal diverticulum： A case report and review of the literature

Duodenal diverticula are a relatively common condition. They are asymptomatic, unless they become complicated, with perforation being the rarest but most severe complication. Surgical treatment is the most frequently performed approach. We report the case of a patient with a perforated duodenal diverticulum, which was diagnosed early and treated conservatively with antibiotics and percutaneous drainage of secondary retroperitoneal abscesses. We suggest this method could be an acceptable option for the management of similar cases, provided that the patient is in good general condition and without septic signs.     

Presence of immunoreactive growth hormone and prolactin in the ovine pineal gland

Abstract: The use of antisera raised against bovine growth hormone (GH) and ovine prolactin (PRL) enabled the detection of related immunoreactive (ir) sequences of proteins in ovine pineal tissue. The isolation of PRL-like ir-material was accomplished using a 0.25 M ammonium sulphate (pH 5.5) extraction followed by ethanol precipitation, whereas the resulting 2.0 M ammonium sulphate (pH 7.0) precipitate contained a GH-like immunoreactivity. Gel chromatography of the GH-like immunoreactivity (Sephadex G-100) indicated the presence of several GH-like fragments ranging in the M_r range of 7,000 to 55,000. Analyses of the PRL-like ir-material found in pineal tissue on HPLC using a TSK 545-DEAE column led to the resolution into a single peak of immunoreactivity. A single peak of activity was also observed following chromatofocusing and hydrophobic interaction chromatography of the ir-peak from the TSK 545-DEAE column. The PRL-like ir-material inhibited the binding of [¹²⁵I]ovine PRL-S14 to anti-ovine PRL antibodies without showing an affinity for binding to anti-rat PRL or anti-bovine GH antibodies. Scatchard analysis of the binding of pineal PRL-like ir-material and pituitary ovine PRL-S14 to liver membranes from day-20 pregnant rats revealed similar affinity constants (K_a of 4.7 ± 0.2 × 10⁹ M^-1). In addition, the replication of Nb 2 Node rat lymphoma cells was stimulated by pineal PRL-like ir-material, an effect known to be specific for lactogenic hormones. The pineal PRL-like immunoreactivity appeared on sodium dodecyl sulfate polyacrylamide gels as a single major band of M_r 24,000. The functional status of PRL-and GH-like ir-material in the ovine pineal remains to be determined, but evidence is presented that the overall protein synthesis rate of the rat pineal responded to circulating concentrations of PRL.     

Microbiology of human immunodeficiency virus anorectal disease

PURPOSE: Individuals who are seropositive for the human immunodeficiency virus are at high risk for opportunistic infection and anorectal disorders. Little prospective information is available regarding anorectal pathogens in these patients. METHODS: One hundred sixty-three HIV-seropositive patients presented to the colorectal clinic between 1989 and 1992. Forty-seven (29 percent) patients were thought to have an infectious process and were prospectively studied using a standardized multiculture protocol. RESULTS: Mean age was 33 (range, 19–59) years. All were male; high-risk behavior accounted for 87 percent of HIV transmissions. Presenting complaints included anorectal pain (79 percent), pus per anum (28 percent), and blood per anum (26 percent). Examination revealed perianal tenderness (60 percent), condyloma (38 percent), perianal ulcers (38 percent), and anal fissures (34 percent). Sixty-six sets of cultures were performed; 28 patients had one set, 15 had two sets, and 4 had three sets. Thirty-two of these 47 patients (68 percent) had positive cultures including herpes (50 percent), cytomegalovirus (25 percent),Neisseria gonorrhoeae (16 percent), chlamydia (16 percent), acidfast bacilli (2 percent), and others (9 percent). Six of 32 patients with positive cultures had more than one organism cultured. Sixteen (50 percent) patients with positive cultures were treated medically, 8 (25 percent) were treated surgically and 8 (25 percent) were treated with both modalities. Sixty-one procedures were performed on 17 patients for condylomata. Eighteen patients had 20 procedures for abscesses, 50 percent of whom had positive cultures for other than common bowel flora; all improved. Fourteen patients underwent 33 procedures for perianal fistulas.Mycobacterium fortuitum was cultured from one patient who required 13 procedures for abscesses and fistulas. Forty-five (96 percent) patients were followed for an average of 12.5 months ±2.9 SEM (range, 1–94 months). Symptoms were improved or resolved in 22 of 32 (69 percent) patients with positive cultures and in 11 of 13 (84 percent) with negative cultures. CONCLUSIONS: Specific pathogens may often be identified in human immunodeficiency virus-seropositive patients with anorectal disorders if aggressively sought. Although patients without specific pathogens identified may be expected to improve with planned empiric treatment, positive identification allows more directed therapy.