Anti-capsular immunity to Streptococcus pneumoniae serotype 22F prevents bacterial transmission in murine colonization and influenza virus co-infection models

We evaluated the effectiveness of anti-22F serotype immunity in the prevention of Streptococcus pneumoniae (Spn) bacterial transmission during colonization and influenza virus co-infection. Mice were immunized with 22F formulation and later colonized with Spn or co-infected with Spn and influenza virus. The 22F antisera exhibited strong reactivity to 22F bacteria and promoted the opsonic uptake of Spn by the neutrophils. The 22F vaccination led to a significant reduction of bacterial densities in the nasopharynx and prevented bacterial transmission during colonization and co-infection. The transfer of 22F antisera to infant mice resulted in reduced bacterial transmission in colonization and co-infection models.     

荔湾区2010～2013年艾滋病自愿咨询检测结果及影响因素分析

目的探讨艾滋病自愿咨询人群血清学检测结果及其影响因素,为荔湾区今后更好的开展VCT服务提供依据。方法以2010~2013年在荔湾区各VCT门诊接受VCT服务并登记上报的求询者作为研究对象,按照《全国艾滋病检测技术规范(2009)》要求开展HIV抗体初筛检测,阳性标本合做梅毒、丙肝、乙肝检测。采用非条件Logistic回归分析影响艾滋病自愿咨询人群艾滋病感染的相关因素。结果共调查艾滋病自愿咨询检测者6 423人,其中男性2 787人,占43.4%,女性3 636人,占56.6%;年龄集中在(32.4±10.8)岁。HIV抗体阳性98例,占1.5%,其中1例同时呈HIV、梅毒、丙肝、乙肝阳性,合并四重感染率为1%;HIV、丙肝合并感染者有42例,双重感染率为42.9%;HIV、梅毒合并感染有20例,双重感染率为20.4%;HIV、乙肝合并感染有8例,双重感染率为8.16%。经Logistic回归分析显示:对艾滋病自愿咨询检测人群艾滋病感染的影响因素是年龄、职业和人群特征。年龄段在21~60岁,吸毒者、同性恋、阳性配偶者为艾滋病感染的风险人群。结论政府组织与各部门共同担责,改进并完善自愿咨询检测服务,加强对艾滋病感染风险人群检测,向"零"艾滋迈进。     

粤东地区毛细支气管炎病毒病原谱的变迁探究

目的探讨近年来粤东地区毛细支气管炎病毒病原学的构成现状。方法收集粤东地区2007年7月至2010年6月3年间毛细支气管炎患儿的咽拭子共508份,采用多重PCR方法检测呼吸道合胞病毒、腺病毒、流感病毒A型、流感病毒B型、副流感病毒1型、副流感病毒3型、鼻病毒、人类博卡病毒、人类偏肺病毒、WU多瘤病毒,共8种lO型病毒。结果①508例患儿中男374例（73．6％）,女134例（26．4％）。②508例患儿中1岁以下年龄组393例（77．4％）,病毒检出率为77．2％;1岁以上年龄组115例（22．6％）,病毒检出率为22．8％。③2007年7至2008年6月病毒阳性率为47．5％（77／162）,病毒检出第1位为呼吸道合胞病毒（33．7％）,新发现呼吸道病毒（人类博卡病毒、人类偏肺病毒、wu多瘤病毒）占14．3％;2008年7月至2009年6月病毒阳性率为51．7％（124／240）,病毒检出第1位为流感病毒A型（38．4％）,新发现呼吸道病毒占6．4％;2009年7月至2010年6月病毒阳性率为45．3％（48／106）,病毒检出第1位为鼻病毒（22．4％）,新发现呼吸道病毒占20．9％。④3年间病毒混合感染率分别为20．8％、42．7％、27．1％。结论①毛细支气管炎患儿中男孩多见,1岁以下年龄组发病率及病毒检出率均高于1岁以上年龄组。②鼻病毒、流感病毒A型在不同年度是小儿毛细支气管炎首位病原体,既往研究中占首位的呼吸道合胞病毒有逐年下降趋势。③新发现呼吸道病毒在小儿毛细支气管炎病例中检出,并有逐年上升趋势。④毛细支气管炎病例中存在不同病毒混合感染的现象。     

慢性丙型肝炎患者混合或重叠感染其他病原体状况分析

目的了解丙型肝炎病毒（HCV）感染者混合或重叠感染乙型肝炎病毒（HBV）、人免疫缺陷病毒（HIV）和梅毒螺旋体（TP）的状况,为HCV感染的防治提供依据。方法采用ELISA法检测乙型肝炎病毒标志物、抗TP和抗HIV;采用化学发光法检测抗HCV;采用蛋白印迹法确认HIV感染。结果在169例HCV感染者中,重叠感染HBV 25例（14.8%）、HIV 4例（2.4%）、TP 9例（5.3%）,重叠感染HBV和TP 2例（1.2%）,重叠感染HBV和HIV 2例（1.2%）;静脉吸毒者重叠感染HIV（6.7%）和TP（11.1%）的比例均明显高于非静脉吸毒者（P〈0.05）;男性患者重叠感染HBV的比例（19.7%）明显高于女性患者（3.8%,P〈0.01）,女性患者重叠感染TP的比例（11.5%）明显高于男性患者（2.6%,P〈0.05）。结论随着感染方式的多元化,慢性丙型肝炎患者重叠感染其他病原体的情况更加常见。     

Early infection with Leishmania major restrains pathogenic response to Leishmania amazonensis and parasite growth

Experimental models of infection with Leishmania spp. have provided knowledge of several immunological events involved in the resistance mechanism used by the host to restrain parasite growth. It is well accepted that concomitant immunity exists, and there is some evidence that it would play a major role in long-lasting acquired resistance to infection. In this paper, the resistance to Leishmania amazonensis infection in C57BL/6 mice infected with Leishmania major was investigated. C57BL/6 mice, which spontaneously heal lesions caused by infection with L. major, were infected with L. amazonensis at different times before and after L. major. We demonstrated that C57BL/6 mice previously infected with L. major restrain pathogenic responses induced by L. amazonensis infection and decrease parasite burdens by one order of magnitude. Co-infected mice showed production of IFN-gamma in lesions similar to mice infected solely with L. major, but higher TNF-alpha and nitric oxide synthase (iNOS) mRNA expression was observed. Surprisingly, the restrained pathogenic response was not related to IL-10 production, as evidenced by lower levels of both mRNA, protein expression in lesions from co-infected mice and in co-infections in IL-10(-/-) mice. Examination of the inflammatory infiltrate at the site of infection showed a reduced number of monocytes and lymphocytes in L. amazonensis lesions. Additionally, differential production of the CCL3/MIP-1 alpha and CCL5/RANTES was observed. We suggest that the control of lesion progression caused by L. amazonensis in C57BL/6 mice pre-infected with L. major is related to the induction of a down-regulatory environment at the site of infection with L. amazonensis.     

Immunogenicity and protective efficacy of monovalent PCVs containing 22F and 33F polysaccharides in mouse models of colonization and co-infection

BackgroundIn the current transmission, we studied the immunogenicity and protective efficacy of serotypes 22F and 33F in the prevention of colonization and of invasive Streptococcus pneumoniae (Spn) pathogenesis during an influenza co-infection. Serotypes 22F and 33F are emerging Spn serotypes, which are not part of currently administered pneumococcal conjugate vaccine formulations (PCVs). Spn serotype 6A is an ingredient in the currently administered PCV13 vaccine and was therefore included in the study as a control.MethodsAdult (six weeks) and infant (two weeks) C57BL/6 mice were intranasally infected in the nasopharynx (NP) with Spn serotypes 22F, 33F, or 6A. Influenza A H1N1 A/Puerto Rico/8/193 virus (PR8) was introduced one day after the NP Spn colonization. In an immunization challenge study, mice were vaccinated with monovalent 22F, 33F, or 6A polysaccharide conjugated to the CRM₁₉₇ antigen. The immunized mice were colonized or co-infected to study the vaccines efficacy.ResultsAll three Spn serotypes established colonization in adult and infant mice. The co-infected mice showed an increase in Spn NP density. Invasive Spn infection (bacteremia) was observed following the co-infection with serotypes 22F and 6A but not 33F in adult mice, whereas infant mice developed bacteremia following co-infection with all three Spn serotypes. The vaccinations led to robust serum antibody responses to capsular polysaccharides 22F, 6A, and less for 33F. The vaccinations resulted in reductions of Spn NP colonization density for all three serotypes, prevention of bacteremia, and increased survival with Spn serotypes 22F and 6A. Passive transfer of antisera was associated with a reduction of Spn colonization densities in infant mice.ConclusionVaccinations with monovalent 22F, 33F, or 6A formulations protect against Spn colonization, and the efficacy of the 22F vaccination was comparable to the 6A vaccination in preventing an invasive Spn bacterial infection during an influenza co-infection.     

我国西南部彝族聚居区HIV、HBV感染及其影响因素分析

目的 了解我国西南部彝族聚集区人群HIV、HBV感染的流行病学特征及其影响因素.方法 采取整群抽样的方法,在西南部某彝族聚集区艾滋病高流行区抽取1个流行乡镇作为研究现场,进行人群HIV、HBV感染筛查和问卷调查,收集调查对象的社会人口学基本资料、感染相关危险因素,并进行相关实验室检测.结果 共调查2 290名当地成年居民,该乡人群HIV感染率为7.9％,HBV感染率为3.1％,HIV/HBV共感染率为1.2％.对于HIV感染,小学及以上文化程度(OR=3.28,95％CI:1.54 ～ 6.96)、有吸毒史(OR=46.32,95％CI:15.30～140.25)、配偶有吸毒史(OR=3.52,95％CI:1.33 ～ 9.30)、配偶HIV感染史(OR=9.56,95％CI:3.49～26.20)是危险因素,家庭年总收入≥5 000元的人群感染HIV的危险性明显低于家庭年总收入＜1 000元的人群(OR=0.14,95％CI:0.03 ～ 0.66),家庭年总收入1 000 ～3 000元的人群感染HIV的危险性明显低于家庭年总收入＜1 000元的人群(OR=0.28,95％CI:0.11～0.68),有打工史的人群感染HIV危险性明显低于其他人群(OR=0.33,95％CI:0.15～ 0.72).对于HBV感染,有打工史是危险因素(OR=2.48,95％CI:1.16 ～ 3.42).对于HIV/HBV共感染,配偶有HIV感染史是危险因素(OR=6.04,95％CI:1.28 ～ 28.48).结论 该彝族聚居区人群HIV疫情较为严重,应加强艾滋病防治的宣传教育、针具交换以及美沙酮替代治疗等防治工作来控制当地艾滋病的传播.     

黑龙江省旅游区蜱伯氏疏螺旋体和斑点热群立克次体复合感染的动态调查

目的 了解黑龙江省旅游区蜱伯氏疏螺旋体和斑点热群立克次体复合感染的动态变化.方法 运用PCR方法检测2010年捕获蜱中两种病原感染状况并测序进行序列分析.结果 在威虎山和镜泊湖景区采集点捕获蜱标本共849只.两地优势蜱种分别为全沟硬蜱和嗜群血蜱,其中伯氏疏螺旋体和斑点热群立克次体感染率分别为26.15％、10.05％和0.00％、13.33％,提示全沟硬蜱复合感染.两地优势蜱种活动高峰分别出现在7月和6月上旬,蜱携带病原率因时间差异而不同.序列分析显示旅游区伯氏疏螺旋体有3种基因型,除B.garinii型、B.afzelii型外,首次在东北地区发现B.valaisiana-like group型.对斑点热群立克次体序列分析表明,所得两序列分别与Rickettsia sp.HL-93和Rickettsia sp.H820,其同源性为100％.结论 两旅游区蜱中存在伯氏疏螺旋体和斑点热群立克次体复合感染,且携带的基因类型存在多样性;动态调查显示蜱种、蜱密度的分布以及蜱携带病原状况因生境、时间和人群的不同而有差异.     

广东省单纯丙型肝炎病毒及其与人类免疫缺陷病毒共感染者丙型肝炎病毒的基因亚型分析

目的 了解广东省人类免疫缺陷病毒(HW) /HCV共感染者与单纯HCV感染者的感染途径、HCV的基因亚型分布及其遗传特征,为丙型肝炎病毒感染的治疗与预防提供依据. 方法采用巢式逆转录-聚合酶链反应扩增广东省95例HIV/HCV共感染者及99例单纯HCV感染者HCVNS5B基因区域,扩增产物测序后进行HCV基因亚型分析,遗传分析利用MEGA4软件.不同种基因亚型型内基因距离以碱基置换率表示.结果 HIV/HCV共感染者HCV有5种基因亚型,其中6a型占53.7％ (51/95)、3a型占17.9％ (17/95)、1b型占15.8％ (15/95)、3b型占11.6％ (11/95)、1a型占1.0％(1/95);1b亚型内基因距离为6.30％±1.27％,高于其他基因亚型.HIV/HCV共感染者主要通过静脉注射毒品感染(75/95,78.9％),其基因亚型主要为6a型,占60.0％ (45/75).单纯HCV感染者HCV有7种基因亚型,其中1b型占67.7％ (67/99)、6a型占17.2％(17/99)、3a型占6.1％ (6/99)、2a型占5.％(5/99)、3b型占2.0％(2/99)、4a型占1.0％ (1/99)、5a型占1.0％(1/99);1b亚型内基因距离为5.17％±1.03％,高于其他基因亚型.单纯HCV感染者主要通过输血或血液制品感染(80/99,80.8％),其HCV基因亚型主要为1b型,占76.2％ (61/80).结论 广东地区HIV/HCV共感染者及单纯HCV感染者HCV基因亚型呈现多样性,HIV/HCV共感染者与单纯HCV感染者主要感染途径不同,HCV主要基因亚型也不同.