新生隐球菌毒力因子的信号调节

新生隐球菌为一种普遍存在的异宗交配的腐生担菌纲类真菌,是少数人类机会性致病真菌之一,其利用复杂的信号途径来感应生存环境、控制生殖及多种致病因素.已经被系统研究的信号途径包括G蛋白-环磷酸腺苷-蛋白激酶A、神经钙蛋白-钙调节蛋白、促分裂原激活蛋白激酶、Ras信号途径等.概述这4种主要信号途径的作用,以期通过对这些传导途径各个环节的了解,为寻找新的药物靶点,治疗新生隐球菌病提供帮助.

Abstract：

Cryptococcus neoformans, as a ubiquitous heterothallic basidiomycetous fungus,is also one of few opportunistic human fungal pathogen.It utilizes complex signaling pathways to sense environments and control reproduction and virulence factors.Well-studied signaling pathways in Cryptococcus neoformans include G protein-cyclic adenosine monophosphate-protein kinase A, calcineurin-calmodulin ,mitogen-activated protein kinase and Ras signaling pathway.This review mainly describes the role of these four signaling pathways,so as to provide clues to the search for new drug targets for the treatment of Cryptococcus neoformans infection by improving the understanding of these signaling transduction pathways.     

黑素与新生隐球菌

黑素的产生与多种微生物的毒力相关.新生隐球菌主要通过酚氧化酶(漆酶)合成黑素,黑素主要通过抵抗宿主微生物杀伤机制和影响宿主免疫应答来致病.主要就新生隐球菌黑素的微观结构、生物合成,漆酶的分子调节,黑素与新生隐球菌毒力的关系,黑化对真菌生存的影响及与抗真菌治疗的关系等方面进行概述,以期通过对黑素特征的理解为抗真菌药物的开发和对疾病的治疗策略选择提供帮助.

Abstract：

The production of melanin is associated with the virulence of various microorganisms.Cryptococcus neoformans produces melanin mainly via phenoloxidase(laccase)pathway.Melanin contributes to virulence likely by reducing the susceptibility of melanized fungi to host defense mechanisms and affecting immune responses in infected hosts.This review mainly focuses on the microstructure and biosynthesis of Cryptococcus neoformans melanin, molecular regulation of laecase, relationship between melanin and Cryptococcus neoformans virulence, effects of melanization on the survival of fungi, relationship between melanization and antifungal treatment, ete, which may facilitate the design and development of antifungal agents and strategies.     

生殖器疱疹动物模型的建立及应用

生殖器疱疹主要是由2型人类单纯疱疹病毒引起的性传播疾病.在动物阴道内注射病毒液可以建立生殖器疱疹动物模型,在此基础上还可以进一步建立复发感染模型.利用雌性豚鼠建立生殖器疱疹动物模型对于需要观察皮损变化方面的药效学等研究是较为理想的选择.通过观察豚鼠/小鼠外阴及阴道皮损病变情况并进行评分可以用于生殖器疱疹发病机制的研究,还可以用于抗疱疹病毒新药和疫苗的研究.

Abstract：

Genital herpes is a kind of sexually transmitted disease mainly caused by herpes simplex virus type 2(HSV-2). Injecting virus into the vagina of animals is a common method to establish animal models of genital herpes, which can be used as a basis for the building of recurrent infection models. It is an ideal option to set up animal models of genital herpes by using femal guinea pigs for the observation of drug efficacy in skin lesions. To assess the lesion changes in vulva and vagina of guinea pigs or mice after the inoculation by a scoring method may be used to study the pathogenesis of genital herpes and to develop new antiviral agents and vaccines.     

荚膜在小鼠原发性皮肤新生隐球菌感染中的作用

目的探讨新生隐球菌多糖荚膜在小鼠原发性皮肤新生隐球菌感染中的作用。方法按照笔者建立的原发性皮肤隐球菌感染模型构建方法,将新生隐球菌标准野生株B3501与荚膜缺陷株cap64分别皮内接种于免疫抑制与非抑制的BALB/c小鼠,皮损真菌培养与组织病理检查确证感染。观察2种隐球菌感染的病程,比较皮损形成与消退的时间。结果野生株与荚膜缺陷株新生隐球菌皮下接种于BALB/c小鼠后,均可以在免疫抑制与非抑制的BALB/c小鼠皮肤上产生结节、丘疹、溃疡、传染性软疣样皮损,皮损可以自愈,真菌培养与病理确证为隐球菌感染。2种菌株感染的病程差异无显著性意义。结论野生株与荚膜缺陷株新生隐球菌均可以造成BALB/c小鼠相似的皮肤感染。荚膜可能不是小鼠皮肤隐球菌感染的主要毒力因子。     

泌尿生殖道沙眼衣原体感染的流行病学进展

沙眼衣原体是一种常见的性传播疾病病原体,可通过性传播和垂直传播.泌尿生殖道沙眼衣原体感染率和发病率逐年增加,且在国内外不同地区和人群中的流行趋势及基因型分布有所不同.沙眼衣原体能导致多种泌尿生殖系统疾病,年轻女性、多性伴者、男同性恋者均是沙眼衣原体感染的高危人群.概述近年来泌尿生殖道沙眼衣原体感染流行病学研究,为进一步的研究和预防提供参考.

Abstract：

Chlamydia trachomatis (CT) is a common pathogen spread through sexual and mother-tochild transmission. There has been a year-by-year increase in the infection rate of CT and incidence rate of CTrelated diseases. The prevalence trend and genotype distribution of CT vary with areas and populations at home and abroad. CT can cause various urogenital tract diseases. Young women, people with multiple sexual partners and homosexual men all belong to populations at a high risk for CT infection. This article describes recent epidemiology of genital CT infection so as to provide a reference for further researches in and prevention of CT infection.     

新生隐球菌多糖荚膜研究进展

新生隐球菌作为一种条件致病菌日益受到重视,其多糖荚膜是第一个被明确的毒力因子。本文从多糖荚膜的生化组成及分型,可能的致病机理(抑制吞噬、激活补体、抑制细胞因子释放等),抗新生隐球菌抗体的作用及荚膜形成有关基因研究现状等方面进行综述。     

Role of β2-microglobulin in uremic patients may be greater than originally suspected

The role of beta2-microglobulin(β2M) in dialysisrelated amyloidosis as a specific amyloid precursor was defined in the 1980 s. Studies in those years were largely related to β2M amyloidosis. In 2005, for what was probably the first time in the available literature, we provided data about the association betweenβ2M and early-onset atherosclerosis in hemodialysis patients without co-morbidities. In recent years, the role of uremic toxins in uremic atherosclerosis and the interest in β2M as a marker of cardiovascular(CV) and/or mortality risk have grown. In the current literature,clinical studies suggest that β2M is an independent, significant predictor of mortality, not only in dialysis patients, but also in predialysis patients and in the highrisk portion of the general population, and it seems to be a factor strongly linked to the presence and severity of CV disease. It is still unknown whether β2M is only a uremic toxin marker or if it also has an active role in vascular damage, but data support that it may reflect an increased burden of systemic atherosclerosis in a setting of underlying chronic kidney disease. Thus, although there have been some inconsistencies among the various analyses relating to β2M, it promises to be a novel risk marker of kidney function in the awareness and detection of high-risk patients. However, more research is required to establish the pathophysiological relationships between retained uremic toxins and further biochemical modifications in the uremic milieu to get answers to the questions of why and how. In this review, the recent literature about the changing role of β2M in uremic patients will be examined.     

隐球菌致病因素和宿主防御机制的研究进展

新型隐球菌最特征性的致病因子是它的多糖荚膜,无荚膜菌株的致病性较正常有荚膜者低.从AIDS病人身上分离的菌株是小荚膜的,这与在动物身上培育病原体形成的大荚膜相反.与A或D型引起的感染相比,B或C型引起感染的治疗时间明显延长.有趣的是,伴有隐球菌感染的AIDS病人几乎总是A/D型感染.宿主的吞噬细胞在一定条件下是可以杀真菌的,但是,此作用明显地受到一些因素的影响.     

Influence of an anti-integrin α6 monoclonal antibody on the in vitro infection of human HaCaT keratinocytes with human papillomavirus (HPV) 6/11 virus particles

Objective To investigate the influence of an anti-integrin α6 monoclonal antibody (GoH3) on the in vitro infection of a human keratinocyte cell line HaCaT with HPV6/11 virus particles (VP). Methods HaCaT cells were infected in vitro with 4 different concentrations of HPV6/11 VP alone, HPV6/11 VP of 106 copies/ml after incubation with 6 different dilutions of GoH3, or 8 clinical isolates of HPV6/11 VP of 106 copies/ml before or after the incubation with 1∶ 100 dilution of GoH3. After additional culture, the infected HaCaT cells were collected and fluorescence quantitative (FQ)-PCR was performed to detect the HPV DNA load in cells. The inhibition rate of CoH3 on the infection was calculated. Results The viral load was different among the HaCaT cells infected with different concentrations of HPV6/11 VP (P < 0.01). The inhibition rate on the infection positively correlated with the concentration of CoH3 when the dilution was more than 1∶ 100; however, when the dilution was less than 1∶ 100, the increase in CoH3 concentration had no influence on the inhibition rate. The average viral load in HaCaT cells infected with clinical isolates of HPV6/11 VP was (5.81 ± 2.51) × 104 copies/ml in the absence of GoH3, (3.02 ± 1.21) × 104 copies/ml with the presence of CoH3, and the average inhibition rate of GoH3 was (46.9 ± 4.7)%. Conclusions GoH3 could partially suppress the adhesion of HPV6/11 VP to HaCaT cells, hinting that integrin a6 is an important HPV6/11 VP receptor on host cells.     

Influence of an anti-integrin α6 monoclonal antibody on the in vitro infection of human HaCaT keratinocytes with human papillomavirus (HPV) 6/11 virus particles

Objective To investigate the influence of an anti-integrin α6 monoclonal antibody (GoH3) on the in vitro infection of a human keratinocyte cell line HaCaT with HPV6/11 virus particles (VP). Methods HaCaT cells were infected in vitro with 4 different concentrations of HPV6/11 VP alone, HPV6/11 VP of 106 copies/ml after incubation with 6 different dilutions of GoH3, or 8 clinical isolates of HPV6/11 VP of 106 copies/ml before or after the incubation with 1∶ 100 dilution of GoH3. After additional culture, the infected HaCaT cells were collected and fluorescence quantitative (FQ)-PCR was performed to detect the HPV DNA load in cells. The inhibition rate of CoH3 on the infection was calculated. Results The viral load was different among the HaCaT cells infected with different concentrations of HPV6/11 VP (P < 0.01). The inhibition rate on the infection positively correlated with the concentration of CoH3 when the dilution was more than 1∶ 100; however, when the dilution was less than 1∶ 100, the increase in CoH3 concentration had no influence on the inhibition rate. The average viral load in HaCaT cells infected with clinical isolates of HPV6/11 VP was (5.81 ± 2.51) × 104 copies/ml in the absence of GoH3, (3.02 ± 1.21) × 104 copies/ml with the presence of CoH3, and the average inhibition rate of GoH3 was (46.9 ± 4.7)%. Conclusions GoH3 could partially suppress the adhesion of HPV6/11 VP to HaCaT cells, hinting that integrin a6 is an important HPV6/11 VP receptor on host cells.     

Persistent cellulitis in a patient receiving renal dialysis

Cryptococcus neoformans, an opportunistic fungus, may cause cutaneous disease by dissemination from primary lung infection or, more rarely, by direct cutaneous inoculation. Cellulitis in an immunocompromised host who does not respond to conventional antibacterial therapy should alert the physician to consider other diagnoses, including cryptococcal skin infection.     

新生隐球菌不同变种所致小鼠原发性皮肤感染的比较

目的：探讨新生隐球菌不同变种在原发性小鼠新生隐球菌皮肤感染中的作用。方法：按照我们建立的原发性皮肤隐球菌感染模型的方法，将新生隐球菌新生变种标准野生株B3501与格特变种标准株ATCC32609分别皮内接种于免疫抑制与非抑制的BALB／c小鼠，皮损真菌培养与组织病理检查确证感染。观察2种隐球菌感染的病程，比较皮损形成与消退的平均时间。结果：2种变种的新生隐球菌皮下接种于BALB／c小鼠后，可以在免疫抑制与非抑制的BALB／c小鼠皮肤上产生丘疹、结节、溃疡、传染性软疣样皮损，皮损可以自愈，真菌培养与病理确证为隐球菌感染。2种菌株只在免疫正常小鼠的皮损形成时间上存在差异。结论：新生变种与格特变种的新生隐球菌均可以造成BALB／c小鼠相似的皮肤感染。推测2种变种对原发性皮肤感染的致病力可能无差异，新生变种发病较多可能与其分布有关。     

新生隐球菌cap60荚膜缺陷株转化系统的构建

目的 构建新生隐球菌荚膜缺陷株ｃａｐ６０的转化系统。方法与结果：（１）在新生隐球菌的荚膜缺陷株ｃａｐ６０中利用５－氟乳清乳（５－ＦＯＡ）反选择法筛选到一个尿嘧啶合成基因突变株。（２）利用带有以新生隐球菌ｕｒａ５基因为选择标记的质粒载体ｐＣｎｔｅｌｌ－ｄ通过电转化法和化学转化法成功地转化该ｕｒａ５突变株。     

Generalized Cryptococcus albidus in an immunosuppressed patient with palmopustular psoriasis

Cryptococcal infection is relatively uncommon, except among immunocompromised individuals. The most common human pathogenic species is Cryptococcus neoformans. Virtually all organs can be affected, particularly the central nervous and pulmonary systems. The prototypical manifestations of cutaneous cryptococcal infection include generalized papules, periorificial acneiform pustules, and molluscumlike vesicles on the upper body. We describe an unusual case of Cryptococcus albidus infection presenting atypically with generalized hemorrhagic plaques. Furthermore, we review the literature on diagnostic evaluation and treatment.     

CUTANEOUS CRYPTOCOCCOSIS: RECURRENCE FOLLOWING ORAL FLUCONAZOLE TREATMENT

A case of recurrent cutaneous cryptococcosis in an immunocompromised patient is described. The patient presented with a non-healing cutaneous ulcer due to infection with Cryptococcus neoformans. Extensive investigation failed to reveal any evidence of associated systemic cryptococcosis. Treatment with oral fluconazole resulted in complete resolution of the ulcer but after several months a second cutaneous cryptococcal lesion appeared, strongly suggesting dissemination from an underlying systemic focus. This case illustrates the hazards associated with making a diagnosis of isolated cutaneous cryptococcosis and the necessity for prolonged follow-up of patients who present in this way.     

新生隐球菌L型致病性的实验研究

以稳定新生隐球菌Ｌ型感染小鼠后，部分脑组织中出现长丝体和巨形体。病原分离，新生隐球菌大小不一、形态不规则。病理学检查，各脏器主要表现为间质性炎症。我们认为：①新生隐球菌Ｌ型致病的特征性表现为间质性炎症；②隐球菌性肉芽肿的形成可能与病灶处新生隐球菌变异成Ｌ型有关。     

国产氟康唑体外和体内抗真菌作用研究

国产氧康唑体外对２５株常见致病真菌以及体内对小鼠感染白念珠菌和新型隐球菌的抗菌作用与酮康唑和两性霉素Ｂ进行了比较。结果表明氟康唑在体外最小抑菌浓度（ＭＩＣ）不如其他两药。而口服氟康唑对感染小鼠的保护作用明显优于酮康唑和两性霉素Ｂ，口服治疗白念珠菌感染小鼠的５０％动物的有效浓度（ＥＢ５０）分别为０．８５ｍｇ／ｋｇ和３９．９８ｍｇ／ｋｇ，口服治疗新型隐球菌感染小鼠的ＥＤ５０分别为３．５４ｍｇ／ｋｇ和８１．６９ｍｇ／ｋｇ。     

PCR检测深部致病真菌感染的研究

目的探讨PCR在可疑深部真菌感染临床标本检测中的应用。方法对60份临床标本分别进行传统真菌培养以及真菌通用引物PCR和三重PCR检测。结果真菌培养阳性共19份，其中白念珠菌10份、烟曲霉2份、新生隐球菌2份、其他菌株5份（包括光滑念珠菌2份、热带念珠菌2份、克柔念珠菌1份）；真菌通用PCR检测共有21份阳性，经三重PCR检测共有15份阳性，分别为白念珠菌10份、烟曲霉3份、新生隐球菌2份。PCR方法与传统培养方法相比，检出率差异无统计学意义。结论PCR检测可疑深部真菌感染临床标本快速简便，稳定性好，敏感性和特异性均较理想，适合临床实验室常规使用。     

新生隐球菌ISC10基因的cDNA克隆及序列分析

目的克隆新生隐球菌ISC10基因(Meiosis-specific protein required for spore formation)的全长cDNA序列,并进行生物信息学分析。方法从新生隐球菌B3501菌株中分离提取总RNA,逆转录成cDNA,运用逆转录-聚合酶链反应(RT-PCR)技术扩增获得新生隐球菌ISC10基因,构建pGM-T/ISC10重组载体,测序后与GenBank中ISC10基因(DQ332212)进行同源性比较和序列分析。结果所克隆的基因共编码267个氨基酸,分子量为31.65KD,与GenBank中ISC10基因(DQ332212)序列同源性达99.10%,编码的蛋白质在67位氨基酸由Ala(丙氨酸)突变为Pro(脯氨酸),233位氨基酸由Thr(苏氨酸)突变为Ser(丝氨酸)。结论所克隆的基因为新生隐球菌的一个新基因,其相关生物学信息的明确,为应用分子生物学技术进一步深入研究新生隐球菌的感染和致病机制奠定了基础。