Habitat influences on diversity of bacteria found on German cockroach in Beijing

Cockroaches are worldwide indoor pests carrying microorganisms of medical importance. German cockroaches （Blattella germanica） were sampled in five habitats （hospital, restaurant, office home, and market） in Beijing, and the bacteria were isolated from their external surface and alimentary tract and identified using a Biolog identification system. Cockroach densities significantly differed among habitats （market 〉 home 〉 office 〉 restaurant 〉 hospital）. However, no significant differences in bacterial abundance carried by individual German cockroaches （of either sex） were found among habitats. The bacterial abundance in the gut was significantly higher than that on the surface. There were no significant differences in bacterial species richness observed among habitats, sex, carrying position or their interaction. Cluster analysis showed that cockroach densities and bacterial abundance found in the market differed significantly from the other four habitats. The bacterial diversity was not significantly reduced in sensitive facilities such as hospital and restaurant, even though pesticide and bactericide were more frequently applied there. The implications of these findings were discussed in this article.

External Bacterial Flora and Antimicrobial Susceptibility Patterns of Staphylococcus spp. and Pseudomonas spp. Isolated from Two Household Cockroaches, Blattella germanica and Blatta orientalis

A study was performed to estimate the prevalence of the external bacterial flora of two domestic cockroaches （Blattella germanica and Blatta orientalis） collected from households in Tebessa （northeast AIgeria）.Three major bacterial groups were cultured （total aerobic, enterobacteria, and staphylococci） from 14 specimens of cockroaches, and antibiotic susceptibility was tested for both Staphylococcus and Pseudomonas isolates. Culturing showed that the total bacterial load of cockroaches from different households were comparable （P〈0.001） and enterobacteria were the predominant colonizers of the insect surface, with a bacterial load of （2.1×10^5 CFU/insect）, whereas the staphylococci group was the minority. Twenty-eight bacterial species were isolated, and susceptibility patterns showed that most of the staphylococci isolates were highly susceptible to chloramphenicol, gentamycin, pristinamycin, ofloxacin, clindamycin, and vancomycin; however, Pseudomonas strains exhibited resistance to amoxicillin/clavulanic acid, imipenem, and the second-generation antibiotic cephalosporin cefuroxime.

Characterization of antennal sensilla of the wood-feeding cockroach Cryptocercus(Blattodea:Cryptocercidae):an exploration of taxonomy

Antennal sensilla are investigated in three xylophagous cockroaches： Cryptocercus meridianus, C. habaensis and C. changbaiensis, using scanning electron microscopy （SEM）. General morphology of the antenna is provided in detail, and no significant differences are found among the three species. Six primary types of sensilla are observed and measured： sensilla chaetica （Ch）, sensilla trichodea （Tr）, sensilla basiconica （Ba）, sensilla coeloconica （Co）, sensilla campaniformia （Ca） and sensilla capitula （Cp）. Sensilla trichodea 1 （Trl） is the most abundant sensillum in all three species. There are some statistical differences between sexes and among species. Comparing Cryptocercus with other cockroaches and termites, we briefly discuss the differences among them in terms of their habitat. According to the statistical analysis performed with the sensilla, these morphological characteristics are not enough to separate the three species and may not be suitable for a classification at species level.

RAPD-PCR Based Marker Approach for the Genetic Differentiation of Two Species of Cockroach （Order-Dictyoptera）

Random amplified polymorphic DNA （RAPD） analysis was conducted for the differentiation of two most commonly occurring insect species Periplaneta americana and Blatella germanicana. This technique is proved to be a quick and effective to establish genetic markers to differentiate morphologically similar populations. During the study cockroach species Periplanata americana and Blatella germanicana were considered. Ten random primers were used for polymerase chain reaction （PCR）. Many of such bands obtained, which differentiate between the two species. On the basis of interpretability, simplicity and reproducibility, six primers P1 （GATGACCGCC）, P3 （GGCACGTAAC）, P6 （GGTGCGCCTT）, P7 （GTCAGAGTCG）, P8 （GTCGCCGTCT） and PI0 （GTGCCCGATG） were considered positive for genetic differentiation and analysis. A series of bands ranging from -300 bp to -1,000 bp obtained indicates that these two species are related, however they exhibit some variations. It has also been observed that the same primers also amplified some DNA fragments of the same size in both the species, which indicates the presence of conserved regions, sharing ancestral relationship. Some of the fragments were unique in both the species which may be used for diagnostic purposes. The study concludes that the RAPD-PCR technique is useful for the study of molecular taxonomy in insects.

Two sex pheromone receptors for sexual communication in the American cockroach

Volatile sex pheromones are vital for sexual communication between males and females.Females of the American cockroach,Periplaneta americana,produce and emit two sex pheromone components,periplanone-A(PA)and periplanone-B(PB).Although PB is the major sex attractant and can attract males,how it interacts with PA in regulating sexual behaviors is still unknown.In this study,we found that in male cockroaches,PA counteracted PB attraction.We identified two odorant receptors(ORs),OR53 and OR100,as PB/PA and PA receptors,respectively.OR53 and OR100 were predominantly expressed in the antennae of sexually mature males,and their expression levels were regulated by the sex differentiation pathway and nutrition-responsive signals.Cellular localization of OR53 and OR100 in male antennae further revealed that two types of sensilla coordinate a complex two-pheromone-two-receptor pathway in regulating cockroach sexual behaviors.These findings indicate distinct functions of the two sex pheromone components,identify their receptors and possible regulatory mechanisms underlying the male-specific and age-dependent sexual behaviors,and can guide novel strategies for pest management.

Molecular Characteristics of Cockroach Allergens

Cockroaches, commonly found in urban dwellings worldwide, have long been considered vectors of various infectious diseases and cockroach allergens are one of the major etiologic risk factors for IgE-mediated allergic respiratory illness throughout the world. A high prevalence of cockroach hypersensitivity in atopic （20-55 %） and asthmatic （49-60 %） populations has been documented. Cockroach allergens with molecular weights ranging from 6 to 120 kD have been identified by various standard immunochemical techniques. This article covers the characteristics of major cockroach allergens that have been purified, sequenced, cloned, and produced as recombinant proteins. Cellular ＆ Molecular Immunology. 2005;2（3）： 177-180.

Prevalence of sensitivity to cockroach allergens and IgE crossreactivity between cockroach and house dust mite allergens in Chinese patients with allergic rhinitis and asthma

Background Cockroaches are an important indoor allergen source causing allergic rhinitis and asthma. The aim of this study was to investigate the cockroach prevalence in mainland of China and the cross-reactivity of IgE between cockroach and house dust mite allergen in Chinese patients.Methods The cockroach sensitization pattern was based on a skin prick test （SPT） obtained from a national multicenter prevalence study, in which 6304 patients from 25 allergy centers across China participated. Factors, including different regions of China, age, gender and the correlations between the American and German cockroaches and house dust mite Der p were investigated. Eighteen out of 1236 clinical sera from south China were selected to perform the cross-inhibition assay between house dust mites and cockroaches.Results Totally 25.7% of patients were SPT positive to the American cockroach （Periplaneta Americana, Per a） and 18.7% SPT positive to the German cockroach （Blattella germanica, Bla g）. The prevalence of positive cockroach SPT was higher in southern than in northern China, higher in adults than in children, and higher in males than in females.Patients had relatively low levels of cockroach SPT reactions, mainly class 1 or 2. Of the SPT positive cockroach patients,88% were also SPT positive to house dust mite （Dermatophagoides pteronyssinus, Der p）. An IgE cross-inhibition study confirmed that Der P sensitization could cause false positive SPT reactions against cockroach.Conclusions A relatively high prevalence of cockroach sensitivity was found in mainland of China. However, a cross-inhibition study showed that only a small number of patients appear to have Bla g and/or Per a as primary sensitizing source. The importance of cockroaches as a risk factor for sensitization and triggers of allergic symptoms in mainland of China needs to be further investigated.

S-烯虫乙酯对德国小蠊的现场控制效果研究

目的探索S-烯虫乙酯对德国小蠊的现场控制效果。方法选择2个农贸市场作为研究对象,实验组使用S-烯虫乙酯药片贴进行德国小蠊控制,对照组使用商家自行购药控制德国小蠊密度。通过比较2个市场的德国小蠊密度变化和发育繁殖情况,评估S-烯虫乙酯对德国小蠊的控制效果。结果实验组在投药30 d后德国小蠊总密度下降明显,密度下降率达到67.11%,若虫密度下降率为79.79%。对照组前60 d总密度变化不大,第90天开始密度上升。统计分析结果表明,实验组与对照组在第90和120天的德国小蠊密度存在显著差异。施药现场带回的德国小蠊若虫中,外形畸形组死亡较早。施药现场带回的10个卵鞘中有3个未孵化,7个卵鞘产生的122只若虫成功羽化40只成虫,其中3个成虫翅膀出现畸形。结论S-烯虫乙酯通过致畸和不育作用,能够减小德国小蠊种群密度,降低其繁殖能力。

2022年上海市黄浦区蜚蠊密度及德国小蠊抗药性监测分析

目的了解上海市黄浦区不同生境蜚蠊密度和种群构成,以及德国小蠊对3种常用杀虫剂的抗药性情况,为有效防治德国小蠊侵害提供科学依据。方法采用粘捕法开展蜚蠊监测,采用药膜法开展德国小蠊抗药性实验测定。结果黄浦区2022年1—12月共布放粘蟑纸1200张,有效粘蟑纸1139张,阳性49张,粘捕率为4.30%,捕获蜚蠊253只,总密度为0.22只/张夜,其中德国小蠊248只,黑胸大蠊3只,美洲大蠊2只。监测结果显示不同生态环境的蜚蠊密度有明显差异,农贸市场密度最高,其次为中小餐饮机构。抗药性结果显示高效氯氰菊酯、乙酰甲胺磷、残杀威对黄浦区德国小蠊现场品系的半数击倒时间(KT50)分别为213.51、155.36、96.02 min,德国小蠊对3种杀虫剂的抗性倍数分别是90.09、3.84、8.45。结论德国小蠊对常用杀虫剂产生了不同程度的抗性,是黄浦区蜚蠊防治的重点。

蜚蠊改善错配修复基因缺失肠癌细胞对氟尿嘧啶敏感性的机制研究

目的:探讨中药蜚蠊改善氟尿嘧啶对错配修复基因缺失(dMMR)肠癌细胞敏感性的相关机制。方法:选择dMMR肠癌细胞,予以不同浓度氟尿嘧啶和蜚蠊作用后,利用MTT法检测两药联合的抑瘤性,根据抑制率计算出治疗指数(CI)值,明确联合增效作用,应用二代基因测序及脂质代谢分析,挖掘出差异代谢基因,数据库分析差异基因与相关机制通路。结果:中药蜚蠊可以改善氟尿嘧啶在HCT116和DLD1肠癌细胞中的疗效,GO功能富集分析和KEGG分析结果显示脂质代谢、自噬调控和凋亡通路发生主要改变,利用LC/MS进行脂质组学检测,共有153个脂质分子发生变化,包括脂肪类、鞘脂代谢物、磷脂代谢物和甘油酯。结论:蜚蠊与氟尿嘧啶联合用于dMMR肠癌细胞具有协同增效作用,可能通过调控代谢通路、自噬及凋亡通路机制改善药物疗效。

2019—2023年合肥市蜚蠊监测结果及德国小蠊抗药性分析

目的了解2019—2023年合肥市蜚蠊种群构成、年度变化及抗药性,为开展蜚蠊防制提供科学依据。方法每年奇数月选择6种生境,采用粘捕法开展蜚蠊密度监测。采用描述性方法分析蜚蠊的种群构成,采用Friedman检验比较不同生境蜚蠊的年度变化规律;采用诊断剂量法判定蜚蠊的抗性种群。结果2019—2023年合肥市共回收有效粘蟑纸6597张,粘捕蜚蠊758只,优势种群为德国小蠊。不同年份蜚蠊种群构成存在统计学差异(χ^(2)=308.382,P<0.05)。蜚蠊平均密度为0.115只/张。2019—2023年蜚蠊密度分别为0.048、0.118、0.189、0.089、0.142只/张。在6种生境中,农贸市场蜚蠊密度最高,为0.261只/张,医院蜚蠊密度最低,为0.005只/张。蜚蠊密度大致呈双峰曲线,高峰期在3月和9月。不同生境蜚蠊密度年际消长差异有统计学意义(F=13.757,P<0.05),不同生境蜚蠊密度季节消长差异有统计学意义(F=30.721,P<0.05)。合肥市德国小蠊对高效氯氰菊酯表现为抗性,对吡虫啉、氟虫腈和残杀威表现为敏感。结论合肥市蜚蠊的粘捕率和密度均较低,建议根据合肥市蜚蠊密度季节消长及抗药性情况开展有针对性的防制。

2022年西安市蟑螂监测

目的了解西安市蟑螂的种群构成、生境分布、季节消长情况,为防治工作提供科学依据。方法采用粘捕法。结果共捕获蟑螂135只,德国小蠊130只,其余5只为褐斑大蠊。蟑螂平均密度为0.032只/张,平均粘捕率为1.51%。农贸市场和餐饮行业中蟑螂密度和粘捕率均较高;不同季节蟑螂密度和粘捕率分布呈单峰曲线,且峰值均在9月。城区年平均蟑螂密度低于郊区。结论农贸市场和餐饮行业仍是蟑螂侵害较高的场所,需要重点关注。

古今蜚蠊的药性、功效与临床应用考证

蜚蠊又名蟑螂,作为传统“四害”之一,鲜有报道总结其作为传统中药的药性、功效与临床配伍应用。以美洲大蠊为代表的蜚蠊科昆虫药用历史悠久,在多种疾病治疗方面展现出良好的药效作用,但其他蜚蠊昆虫如澳洲大蠊、东方蜚蠊没有得到足够的重视及开发、应用。为了深入开发应用蜚蠊科昆虫类药物,首先需要了解其作为药物是否有效,故通过查阅大量本草和医药典籍,从药性、功效、临床应用三方面进行了考证,以挖掘有害昆虫的药用价值,为人类健康服务。

2022年苏州市蜚蠊种群监测及抗药性分析

目的了解苏州市不同生境蜚蠊的种群构成、密度季节变化及德国小蠊的抗药性情况。方法用粘捕法调查蜚蠊密度,用药膜法进行德国小蠊抗药性测定。结果2022年苏州市蜚蠊粘捕率和密度分别为7.20%和0.40只/张,德国小蠊占捕获总数的94.24%,为优势种。蜚蠊粘捕率和密度7月最高,分别为9.73%和0.56只/张,农贸市场蜚蠊密度最高为1.80只/张,不同月份总体蜚蠊密度和农贸市场蜚蠊密度呈显著相关性(r=0.965,P=0.002)。不同生境蜚蠊粘捕率的差异具有统计学意义(χ^(2)=483.489,P<0.001);德国小蠊成虫对高效氯氰菊酯、溴氰菊酯、乙酰甲胺磷、毒死蜱、残杀威抗性倍数分别为3.36、6.18、1.08、1.79、0.79。结论德国小蠊是苏州市蜚蠊优势种,农贸市场蜚蠊密度最高,7月是蜚蠊密度高峰月,德国小蠊对溴氰菊酯为中度抗性,对其他4种杀虫剂为低度抗性。

Kinematics Analysis and Experiment of a Cockroach-Like Robot

This article describes the structure of the cockroach-like robot.Both kinematics and locomotion control are inspired by biological observations in cockroaches.Based on cockroach-like robot kinematics analysis,screw theory,and the production-of-exponential (POE) formula,this paper focuses on the inverse kinematics which uses Paden-Kahan sub-problems to obtain directly the displacement of joint angles.The forward kinematics derives the relationship between joint angles according to the natural restrictions.Then,by using the POE formula,it can deduce the body pose and realize online trajectory control and planning.Through simulation and experimentation,it is proved that the straight-line walking and turning gait algorithms have static stability and the inverse kinematics analysis of cockroach-like robot is correct.

Testing decreasing variabililty of cockroach forewings through time using four Recent species： Blattella germanica, Polyphaga aegyptiaca, Shelfordella lateralis and Blaberus craniifer, with implications for the study of fossil cockroach forewings

Vrsansky, （2000） considered there is decreasing variability in the forewings of cockroaches through time, based on a study of fossil and Recent species. This study tests his theory, based on a study of four Recent species of cockroaches： Blattella germanica （Blattellidae）, Polyphaga aegyptiaca （Polyphagidae）, Shelfordella lateralis （Blattidae） and Blaberus craniifer （Blaberidae）. The new results, based on the coefficient of variation （CV） of the number of veins, indicate that Recent species can be more variable than fossil species and therefore do not support the theory. The results also show that at least 30 complete wings of the same species are required for a reliable CV value that is compa- rable between species.

Derived, still living cockroach genus Cariblattoides （Blattida： Blattellidae） from the Eocene sediments of Green River in Colorado, USA

Cariblattoides labandeirai sp.n. from the Eocene sediments of Green River in Colorado, USA bear only two plesiomorphies, but also several significant autapomorphies within the advanced and highly derived living cockroach genus. Thus, Cariblattoides with extant occurrence in the Caribbean and South America was historically common in the Nearctic, and represents important evidence for the occurrence of derived living genera of cockroaches -50 Ma ago. Generally, the vast majority of living genera were absent during the Palaeocene, thus the diversification of most living cockroach lineages near the Palaeocene/Eocene boundary must have been extremely rapid. Females of living C. suave, the type species, have identical （sophisticated） coloration ofpronotum, but the most related living taxa are C. piraiensis and C.fontesi from Brazil （supported by phylogenetical analysis）.

First molecular genetic evidenee for automictic parthenogenesis in cockroaches

Parthenogenesis is an asexual mode of reproduction that plays an important role in the evolution of sex, sociality, and reproduction strategies in insects. Some species of cockroach exhibit thelytoky, a type of parthenogenesis in which female offspring are produced without fertilization. However, the cytological and genetic mecha? nisms of parthenogenesis in cockroaches are not well understood. Here we provide the first molecular genetic evidence that cockroaches can reproduce through automixis. Using the American cockroach Periplaneta aniericana, we performed microsatellite analysis to investigate the genetic relationship between parthenogenetically produced nymphs and the parent virgin females, and found that all parthenogenetic offspring were homozygous for autosomal microsatellite markers, whereas the female parents were heterozygous. In addition, flow cytometry analysis revealed that the parthenogenetic offspring were diploid. Taken together, our results demonstrate that P. americana exhibits automixis-type thelytoky, in which diploidy is restored by gamete duplication or terminal fusion. These findings highlight the unique reproduction strategies of cockroaches, which are more varied than was previously recognized.

Book review:Cockroaches of Southeastern China

The book, Cockroaches of Southeastern China, wrote by Xianwei Liu, Weibing Zhu, Li Dai and Hanqiang Wang, was published in 2017.In this book,the cockroachs fauna of the Southern China was observed,occupied Shandong, Anhui,Jiangsu, Shanghai, Zhejiang, Fujian, Jiangxi, Taiwan, Guangdong and Hainan Provinces.

济南口岸输入性蜚蠊携带病原体宏基因组分析

目的探讨利用宏基因组分析为济南口岸防控输入性蜚蠊传播疾病提供技术支持。方法选取2022年至2023年6月间济南海关辖区截获送检的623只蜚蠊作为研究对象。每批次40~50只为一组制作成体表样本和组织样本。对样本进行霍乱弧菌、沙门氏菌、志贺氏菌、诺如病毒多重PCR扩增;采用宏基因组测序对蜚蠊携带病原体进行监测分析。结果623只蜚蠊经鉴定均为德国小蠊;霍乱弧菌、沙门氏菌、志贺氏菌、诺如病毒PCR检测均为阴性;15组蜚蠊样本中通过宏基因组检测出蟑螂杆状体细菌、大肠埃希菌、肠球菌属、不动杆菌属、魏斯氏菌属、变形杆菌、克雷伯菌属等多种细菌。结论病原体宏基因组分析可以检出蜚蠊携带的多种病原体,且在大肠杆菌检出方面,灵敏度优于PCR检测技术,口岸需加强蜚蠊监控,及时拦截。