Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Cockroaches”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 235 records · Page 13Linked to original sources

Sequence analysis of the first complete cDNA clone encoding an American cockroach Per a 1 allergen.

C3, designated as Per a 1.0103 according to WHO/IUIS nomenclature, encoding a novel American cockroach allergen of 395 aa (44.6 kDa), is the first complete cDNA clone with a translatable immunoreactive protein among the reported group 1 cockroach allergens. Its deduced amino acid sequence possesses a signal sequence, phosphorylation sites, mitochondrial energy transfer protein signatures, and four repeats each sharing striking similarity with the corresponding repeats of the other cockroach allergens. The latter similarity suggests that the group 1 cockroach allergens might have evolved from a primordial mitochondrial sequence by exon duplication.

Allergens↗

Effects of an allatostatin and a myosuppressin on midgut carbohydrate enzyme activity in the cockroach Diploptera punctata.

Neuropeptides of the cockroach allatostatin (AST) family are known for their ability to inhibit the production of juvenile hormone by the corpora allata of cockroaches. Since their discovery, they have also been shown to modulate myotropic activity in a range of insect species as well as to act as neurotransmitters in Crustaceans and possibly in insects. The midgut of cockroaches contains numerous endocrine cells, some of which produce AST whereas others produce the FMRFamide-related peptide, leucomyosuppressin (LMS). We have determined if ASTs and LMS are also able to influence carbohydrate-metabolizing enzyme activity in the midgut of the cockroach, Diploptera punctata. Dippu-AST 7 stimulates activity of both invertase and alpha-amylase in a dose-dependent fashion in the lumen contents of ligatured midguts in vitro, but not in midgut tissue, whereas the AST analog AST(b)phi2, a cyclopropyl-ala, hydrocinnamic acid analog of Dippu-AST 6, has no effect. Leucomyosuppressin also stimulates enzyme activity in lumen contents only, although the EC50 is considerably greater than for Dippu-AST. Dippu-AST is also able to inhibit proctolin-induced contractions of midgut muscle, and this action had already been described for LMS [18]. Thus, in this organ, AST and LMS have at least two distinct physiological effects.

Animals↗

Evidence from multiple gene sequences indicates that termites evolved from wood-feeding cockroaches.

Despite more than half a century of research, the evolutionary origin of termites remains unresolved [1] [2] [3]. A clear picture of termite ancestry is crucial for understanding how these insects evolved eusociality, particularly because they lack the haplodiploid genetic system associated with eusocial evolution in bees, ants, wasps and thrips [4] [5]. Termites, together with cockroaches and praying mantids, constitute the order Dictyoptera, which has been the focus of numerous conflicting phylogenetic studies in recent decades [6] [7] [8] [9] [10] [11] [12]. With the aim of settling the debate over the sister-group of termites, we have determined the sequences of genes encoding 18S ribosomal RNA, mitochondrial cytochrome oxidase subunit II (COII) and endogenous endo-beta-1, 4-glucanase (EG) from a diverse range of dictyopterans. Maximum parsimony and likelihood analyses of these sequences revealed strong support for a clade consisting of termites and subsocial, wood-feeding cockroaches of the genus Cryptocercus. This clade is nested within a larger cockroach clade, implicating wood-feeding cockroaches as an evolutionary intermediate between primitive non-social taxa and eusocial termites.

Animals↗

A single amino acid change in the para sodium channel protein is associated with knockdown-resistance (kdr) to pyrethroid insecticides in German cockroach.

Previous genetic and pharmacological studies suggest that knockdown-resistance (kdr) to pyrethroid insecticides likely results from a mutation(s) in the para sodium channel gene. In this study, para sodium channel genes from an insecticide-susceptible German cockroach strain, CSMA, and a kdr-type German cockroach strain, Ectiban-R, were cloned and sequenced. Comparison of the nucleotide sequences of paraCSMA and paraEctiban-R revealed two nucleotide differences at nt 1491 and nt 2979, respectively. Only the difference at nt 2979 (G in paraCSMA and C in paraEctiban-R) resulted in an amino acid change (Leu993 in CSMA and Phe993 in Ectiban-R). Leu993/Phe993 is located in the highly conserved membrane-spanning segment 6 of domain II (IIS6). Furthermore, reverse transcription-polymerase chain reaction (RT-PCR) sequence analysis using another two insecticide-susceptible and one kdr German cockroach strain, revealed that C2979 was specifically associated with kdr resistant strains, whereas only G2979 was present in all susceptible strains. These results suggest that a single amino acid change from Leu993 to Phe993 is responsible for the kdr-type resistance in German cockroach.

Amino Acid Sequence↗

Association of recurrent wheezing with sensitivity to cockroach allergen in inner-city children.

BACKGROUND: There are numerous data that show a strong relationship between early exposure and sensitization to indoor allergens and the development of asthma and persistent wheezing in children. Most studies, however, have only examined the prevalence of allergy in children who have been identified as having asthma. OBJECTIVE: To assess the prevalence of positive skin test results to common inhaled allergens and possible association with wheezing in inner-city children being seen in a general pediatric clinic. METHODS: Skin testing to common aeroallergens was performed by the prick-puncture method. Demographic and clinical data were collected. RESULTS: Seventy-five children aged 2 months to 10 years were evaluated. A total of 37% of the children had a positive skin test result to at least one allergen; 29% of the children were sensitive to dust mite, 15% to cockroach, 9% to cat, 7% to mold, 4% to grass, 3% to ragweed, and 1% to dog. Seven (64%) of 11 children with positive skin test results to cockroach had a history of wheezing compared with 21 (33%) of 64 with negative skin test results to cockroach (P = .05). CONCLUSIONS: Our results indicate that in a population of inner-city children not previously identified as atopic, more than a third showed sensitivity to at least one allergen. Although dust mite was the most common allergen to which the children were sensitized, cockroach sensitivity was the only allergen that correlated significantly with previous episodes of wheezing.

Air Pollution, Indoor↗

Possible association between cockroach allergy and HLA class II antigens.

BACKGROUND: Susceptibility to the development of allergic diseases is known to be associated with genetic components, as well as environmental factors. Although the genetics of immunoglobulin E, atopy, and asthma are complex, genetic markers are needed to identify populations at risk and to plan intervention studies. OBJECTIVE: Human leukocyte antigen (HLA) class II genes play a major role in the control of immune response. We investigated the association between HLA class II alleles of DRB1 and DQB1 and the expression of atopy in cockroach-sensitive patients. METHODS: Levels of total and specific immunoglobulin E were determined. Skin prick tests were performed. HLA class II typing was performed by the Polymerase chain reaction with sequence-specific primers. Distribution of the HLA genotypes of 32 cockroach-positive atopic patients from the inner city were compared with those of 32 healthy, nonatopic controls of Turkish Caucasian origin. RESULTS: HLA class II gene analysis showed an increase of the HLA-DRB1*0701 and HLA-DQB1*02 alleles in atopic patients compared with nonatopic controls (31.3% vs 3.1% and 50% vs 15.6%, Pc < 0.036 and Pc < 0.021, respectively). Conversely, HLA-DRB1*15 allele was encountered more frequently in the control subjects. An association between cockroach sensitivity and cutaneous reactivity to other aeroallergens was observed (P < 0.001). CONCLUSIONS: It is suggested that the higher frequencies of HLA-DRB1*0701 and HLA-DQB1*02 alleles are probably related to atopy rather than an association between class II antigens and cockroach allergy in this group of polysensitized, atopic individuals. Further studies may lead to a better understanding of the genetically determined susceptibility, and evaluate the individual effects of each locus (or allele) on sensitivity to specific allergens in the Turkish population.

Animals↗

Short-term effects of extermination and cleaning on cockroach allergen Bla g 2 in settled dust.

BACKGROUND: Although cockroach allergen is an important indoor allergen in poor urban environments, no studies on the effectiveness of measures to reduce allergen levels in indoor environments have yet been published. METHODS: As a model of home extermination, we studied cockroach allergen levels in an urban dormitory that was chronically infested with German cockroaches and that underwent semiannual extermination. Dust samples were collected from 18 bedrooms and 5 kitchens located in the dormitory and were analyzed for Bla g 2 using an immunoassay. RESULTS: We detected allergen in almost every bedroom, with median levels ranging from 3.0 U/g (units/g) in settled dust on the bed, 4.0 U/g on the carpeted floor, and 2.8 U/g in closets. In the kitchen, we found somewhat higher levels, 10.8 U/g on the floor and 2.8 U/g in floor cabinets. Repeated measures of floor dust were similar (median 4.4 and 4.0 U/g) despite weekly vacuum cleaning. In the 2 weeks before extermination, median levels were 5.2 U/g and in the 2 weeks following extermination and regular vacuuming, median levels fell to 0.95 U/g. CONCLUSIONS: We concluded that successful allergen abatement could be accomplished in cockroach infested indoor environments using routine extermination and vacuuming.

Allergens↗

Cockroach and other inhalant allergies in infantile asthma.

BACKGROUND: Infantile asthma is commonly thought to be caused by viral respiratory infections and exposure to second-hand cigarette smoke. Allergy has not been felt to be a major cause of infantile asthma and infants and small children are not commonly skin tested. OBJECTIVE: To determine the frequency of skin test reactivity in asthmatic children less than 3 years of age. METHODS: We evaluated 196 (50 female/146 male) children with infantile asthma for allergy. Infantile asthma was defined as three or more episodes of wheezing in a child less than 3 years of age. A careful environmental history was obtained on all children. All were skin tested to alternaria, cat, dog, cockroach, and house dust mites (HDM) extracts using the prick technique with the Greer Dermapik. RESULTS: Forty-five percent of the infants and children tested had at least one positive skin test. 51/196 (26%) of the children were skin test positive to cockroach, 17.3% to HDM, 13.8% to cat, 6.6% to alternaria, and 6.1% positive to dog. For the 49 children who were less than 1 year of age, 28.5% were positive to cockroach, 10.2% to HDM, 10.2% to cats, 4% to alternaria, and 0% to dog. CONCLUSIONS: Allergy to cockroach and other indoor allergens may be a significant contributor to infantile asthma in a rural setting. Skin testing children with infantile asthma may provide useful information for institution of environmental controls measures in the child's home.

Administration, Inhalation↗

Effects of antibiotics on the survival of Salmonella in the American cockroach.

The faecal survival of Salmonella typhimurium orally administered to restrained American cockroaches maintained on an antibiotic diet was investigated. Significant reductions in median numbers of total aerobic faecal microorganisms were noted in insects fed antibiotics daily, and when Salmonella was introduced to this modified micro-environment, it persisted for 44 days in all specimens. Multiplication of the pathogen was also observed in these insects, with numbers often exceeding 10(3) times that of the initial input. This differs significantly from our previous results showing that the pathogen is unable to multiply in conventional cockroaches. Attempts to restore the normal flora by feeding a faecal suspension from untreated cockroaches resulted in a decrease in numbers of Salmonella excreted, but did not result in their elimination. Carcasses of infected cockroaches retained viable Salmonella for at least 60 days post mortem, or 104 days after the infective meal.

Administration, Oral↗

Cockroaches (Blatta and Periplaneta species) as reservoirs of drug-resistant salmonellas.

A total of 221 cockroaches (Blatta and Periplaneta spp.), collected in hospitals, houses, animal sheds, grocery stores and restaurants, in various parts of South Kanara District, a south-west coastal region of India, were studied bacteriologically for the presence of various salmonellas. Salmonellas were isolated from 4.1% of these cockroaches. Nine strains of salmonellas were recovered, belonging to five serotypes--Salmonella bovismorbificans, S. oslo, S. typhimurium, S. mbandaka and S. braenderup, the former two being the commonest serotypes. All salmonellas were resistant to one or other of 11 antibacterial drugs used in the susceptibility test. Isolation of salmonellas from cockroaches collected from the livestock premises and human dwellings suggested that they may act as significant reservoirs of salmonella in nature. Recovery of serotypes, phage types and R-types that were commonly isolated from humans and animals of this locality, suggested a transmission role for cockroaches. By harbouring potentially pathogenic, drug-resistant salmonellas, these wandering arthropods may pose dangerous infective hazards to humans and animals.

Animals↗

IgE reactivity of tandem repeats derived from cockroach allergen, Bla g 1.

Sensitization to cockroach allergens is associated with the development of asthma. Bla g 1 is a German cockroach allergen that shows allergenic cross-reactivity with American cockroach allergen, Per a 1, and has a molecular structure composed of multiple tandem amino-acid repeats. Two consecutive repeats are not identical but form a duplex that constitutes a basic molecular unit of Bla g 1. By molecular mass, purified natural Bla g 1 would contain approximately two duplexes. We investigated the pattern of IgE antibody binding to this repeated structure, and whether one or two duplexes are sufficient for IgE binding. Recombinant (r)Bla g 1 duplexes were expressed in Escherichia coli and in Pichia pastoris, and analyzed for monoclonal antibody and IgE antibody binding by ELISA and/or immunoblotting. Optimal rBla g 1 expression was obtained using methanol-inducible P. pastoris (> 95% pure protein, yield approximately 48 mg x L(-1)), and rBla g 1 was produced as multiple molecular forms of molecular mass 43, 32, 21 and 6 kDa, that were the result of proteolytic cleavage. There was an excellent correlation between IgE antibody binding to natural and recombinant Bla g 1 (r = 0.91, n = 29, P < 0.001), and immunoblot analysis showed that a single Bla g 1 duplex was sufficient for IgE antibody binding. The rBla g 1 is suitable for structural studies and a candidate for clinical use in diagnosis of cockroach allergy and development of new forms of immunotherapy.

Allergens↗

Invasive disease due to extended spectrum beta-lactamase-producing Klebsiella pneumoniae in a neonatal unit: the possible role of cockroaches.

We recently experienced an outbreak of nosocomial disease due to extended spectrum beta-lactamase-producing Klebsiella pneumoniae in a neonatal unit infested with cockroaches. Organisms isolated from cockroaches were indistinguishable by pulsed-field gel electrophoresis from those colonizing infants or causing clinical disease using. Cockroach elimination together with standard infection-control measures resulted in control of the outbreak. We suggest cockroaches are possible vectors of pathogenic bacteria in the hospital environment.

Animals↗

Pets and cockroaches: two increasing causes of respiratory allergy in indoor environments. Characteristics of airways sensitization and prevention strategies.

The increasing prevalence of allergic sensitization to indoor allergens such as dust mites, pets and cockroaches is the result of the changes in indoor environments induced by human activities. The Westernized lifestyle and the increasing time spent indoors determine a reduction in natural air ventilation and, consequently, higher levels of allergen concentrations and longer exposure to allergens. The major cat allergen Fel d 1 is carried by small-dimension particles (< 5 microm diameter) that readily become airborne and persist immodified for a long time. Fel d 1 must be considered a ubiquitous allergen because it has been found in indoor environments and even in public places where a cat has never been kept. Recent research has demonstrated that clothing of cat owners may contribute to the dispersal of Fel d 1 in cat-free environments. Therefore, washing Fel d 1-contaminated clothes should be considered a simple and effective method for removing this allergen from clothing and, consequently, reducing the risk of Fel d 1 dispersion. Cockroach allergens constitute another important cause of environment-related respiratory allergy and may trigger asthma exacerbations in sensitized individuals. In the prevention of cockroach allergy, the use of chemical agents associated with an intensive vacuum cleaning of indoor environments is an important tool in removing cockroach material containing allergenic proteins. Early recognition of allergy-predisposed babies, monitoring indoor allergens and adequate strategies of allergen avoidance are likely to be important means for reducing the prevalence of bronchial asthma.

Allergens↗

Ecology and elimination of cockroaches and allergens in the home.

Cockroach infestations have been indicated as a major contributor to asthma throughout the world. Several studies have shown that large numbers of asthmatic patients are sensitized to cockroach allergens. Eliminating this pest from homes, schools, and public buildings involves a long-term commitment to a rational extermination process. This article covers the characteristics of the major cockroach species that invade homes, assesses the role of environmental exposure to cockroaches in asthma, and provides an intervention program for their extermination.

Air Pollution, Indoor↗

Induction of IgE antibody responses by glutathione S-transferase from the German cockroach (Blattella germanica).

We report that a major 23-kDa allergen from German cockroach (Blattella germanica) is a glutathione S-transferase (EC 2.5.1.18; GST). Natural B. germanica GST, purified from cockroach body extracts by glutathione affinity chromatography, and recombinant protein expressed in Escherichia coli using the pET21a vector, showed excellent IgE antibody binding activity. B. germanica GST caused positive immediate skin tests in cockroach-allergic patients using as little as 3 pg of recombinant protein. The NH2-terminal sequence of the natural protein and the deduced amino acid sequence from cDNA were identical except for one substitution (Phe9 --> Cys). Assignment of this protein to the GST superfamily was based on binding to glutathione and sequence identity (42-51%) to the GST-2 subfamily from insects, including Anopheles gambiae and Drosophila melanogaster. B. germanica GST contained 18 of the 26 invariable residues identified in mammalian GST by x-ray crystallography and exhibited enzymic activity against a GST substrate. Our results show that cockroach GST causes IgE antibody responses and is associated with asthma. The data strongly support the view that the immune response to GST plays an important role in allergic diseases.

Allergens↗

Novel allergen structures with tandem amino acid repeats derived from German and American cockroach.

Cockroaches produce potent allergens that are an important cause of asthma. The two principal domiciliary cockroach species, Blattella germanica and Periplaneta americana, secrete major allergens, Bla g 1 and Per a 1. Here, we report the molecular cloning of three Bla g 1 cDNA clones, which showed 70% amino acid sequence identity with Per a 1. Plaque immunoassays with human IgE antibodies or murine monoclonal antibodies showed that these allergens were antigenically cross-reactive. The Bla g 1 sequences also showed homology to five previously undefined cockroach allergen sequences. An unusual feature of all these sequences was that they contained multiple tandem amino acid repeats of approximately 100 amino acid residues. Between one and seven repeat units were identified by dot-plot matrix analysis. The sequences also showed homology to a mosquito protein involved in digestion (ANG12 precursor) and to mitochondrial energy transfer proteins. High levels of Bla g 1 were found in cockroach hindgut and proventriculus. Amino acid sequencing of natural Bla g 1 and Per a 1 suggested that these allergens are cleaved by trypsin-like enzymes following secretion into the digestive tract. The repeat sequences appear to have evolved by duplication of an ancestral amino acid domain, which may have arisen from the mitochondrial energy transfer proteins.

Allergens↗

Insecticide resistance in German cockroaches (Blattella germanica) from hospitals and households in Taiwan.

Since a high percentage of cockroach infestation has been determined in hospitals in Kaohsiung, South Taiwan, insecticide resistances may have developed in the cockroach populations. To determine the resistances in cohorts of German cockroach (Blattella germanica) from hospitals and households to organophosphates, carbamates and pyrethroids, cockroaches were trapped from 30 hospitals and 30 households in this area. Bioassays by topical application were then carried out on the first generation bred in the laboratory. Resistance ratio (RR) was determined by comparing the LD50 of the collected cohorts with that of a susceptible cohort. RR ranges of chlorpyrifos, propoxur and cypermethrin in the hospitals were 2.04 - 28.80, 2.86 - 30.86 and 1.95 - 14.05 and those in the household were 1.92 - 17.72, 6.93 - 62.50 and 2.80 - 27.35 respectively. Significant correlations among the RRs of the three insecticides were separately found in the hospitals and households, indicating the existence of cross resistance among the three groups of insecticides. The patterns of propoxur > chlorpyrifos > cypermethrin in hospitals and propoxur > cypermethrin > chlorpyrifos in households reflect that chlorpyrifos is more frequently used in hospitals than in households. In contrast, cypermethrin is used more frequently in households.

Animals↗

Comparative activity of fenoxycarb and hydroprene in sterilizing the German cockroach (Dictyoptera: Blattellidae).

Last-instar German cockroaches, Blattella germanica (L.), were treated topically with the juvenoids, fenoxycarb and hydroprene, and observed for reproductive capabilities during adulthood. Hydroprene had a significantly lower SD50 (dose required to sterilize 50% of the cockroaches) for males (39.82 micrograms/g body weight) compared with females (86.64 micrograms/g body weight). In contrast, SD50's of fenoxycarb did not differ significantly between the sexes (18.04 and 13.66 micrograms/g body weight for females and males) and were significantly lower when compared with SD50's of hydroprene. A strong positive relationship between wing twisting (a morphogenetic effect caused by juvenoids) and sterility was observed among cockroaches treated with 100 and 10 micrograms/microliters of each juvenoid. However, only 16% of females displaying twisted wings were sterile when treated with 1 microgram/microliter of hydroprene. Cockroaches treated with 100 micrograms/microliters of hydroprene lived 10-14 wk fewer than control adults and often attempted a sixth (supernumerary) molt.

Animals↗