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 127 records · Page 7Linked to original sources

Removal of cockroach allergen from inner-city homes.

BACKGROUND: Allergen avoidance has been shown to improve the morbidity and physiology of asthma. Although cockroach allergen has been implicated in chronic asthma, little work has been reported on the feasibility of allergen removal from infested homes. OBJECTIVE: The objective of this study was to examine the effect of professional pest control and home cleaning on cockroach infestation and allergen concentrations in settled dust samples from the kitchens, bedrooms, and television-living rooms of inner-city homes. METHODS: Thirteen homes in inner-city Baltimore, Maryland, received a professional cleaning, with vacuuming and a thorough cleaning in the kitchen. Pest control technicians applied abamectin 0.05% gel to the kitchen and, to a limited extent, to the rest of the home and the cleaning was repeated. Technicians visited monthly from month 2 to month 8 to inspect, collect dust samples, and place passive cockroach traps. Bla g 1 concentrations in dust extract were measured by means of ELISA. RESULTS: The number of cockroaches captured in passive traps decreased rapidly in 11 homes, but complete extermination was achieved in only 7 homes. Bla g 1 concentrations were reduced by 93% in kitchens, 77% in television-living rooms, and 74% in bedrooms. The relative reduction in cockroach allergen was not related to successful extermination or to signs of poor house-cleaning. CONCLUSION: We concluded that cockroach extermination is feasible in inner-city homes but that standard house-cleaning procedures are only partially effective in removing residual allergen over 8 months.

Allergens↗

Toxicity of abamectin to cockroaches (Dictyoptera: Blattellidae, Blattidae).

Abamectin was fed to German cockroaches, Blattella germanica (L.), in non-choice tests. LT50s and LC50s were estimated by probit analysis. The LT50s for the German cockroach ranged from 4.4 to 1.7 d for males, from 9.0 to 2.4 d for females, and from 4.4 to 1.6 d for nymphs for bait concentrations of abamectin between 0.0025 and 0.0500%. The LC50s of abamectin were 0.0110 and 0.0040% from males, 0.0240 and 0.0090% for females, and 0.0200 and 0.0080% for nymphs at 3 and 6 d, respectively. The LT50 values of 0.0550% abamectin bait were 3.4, 3.4, 2.4, 7.5, 2.9, and 4.5 d for Periplaneta americana (L.), P. fuliginosa (Serville), P. brunnea Burmeister, P. australasiae (F.), Blatta orientalis L., and Supella longipalpa (Serville). Although the bait was effective against various cockroach species, time to death for the larger species was longer than for the German cockroach. In preference tests in which male German cockroaches were allowed to feed on rat chow or abamectin bait, all died within 5 d of exposure to abamectin bait. Abamectin bait consumption was not significantly lower than that of untreated rat chow. Arena tests with 0.0550% abamectin bait resulted in 31-75% mortality of German cockroaches after 9 d, with most control being achieved by treating harborages with the bait. The hydramethylnon standard resulted in 65% mortality after 9 d.

Animals↗

Cross-reactivity of IgE-binding components between boiled Atlantic shrimp and German cockroach.

IgE-antibody reactivity to boiled Atlantic shrimp (Pandalus borealis) and German cockroach (Blattella germanica) of sera from 89 patients, sensitive to one or the other, was investigated with an enzymatic immunoassay for specific IgE detection (CAP-FEIA System, Pharmacia, Sweden). IgE serum levels to both antishrimp and anticockroach allergens were found to be positive in 76 of the 89 (85.4%) tested sera. A positive anticockroach IgE was very rare in the absence of detectable antishrimp IgE (five of 89 sera). Linear regression analysis on antishrimp and anti-German cockroach IgE levels-log plot revealed a correlation coefficient (r) of 0.73. Inhibition experiments showed that boiled Atlantic shrimp extract inhibited CAP with German cockroach, and vice versa. Immunoblotting showed the strongest IgE binding for both allergenic extracts between 30 and 43 kDa. By blot inhibition, the binding capacity of German cockroach was totally abolished by Atlantic shrimp extract, while German cockroach extract only partially IgE binding to Atlantic shrimp. Cross-reactivity exists between shrimp, an important food allergen, and German cockroach, which has an increasing role in allergic asthma. It could be important to determine the clinical significance of cross-allergy to both allergens, in which exposures occur in different ways.

Adolescent↗

Sub-lethal exposure of cockroaches to boric acid pesticide contributes to increased Bla g 2 excretion.

BACKGROUND: Several epidemiology studies have found an increase in the major cockroach allergen Bla g 2 with reported pesticide use. AIMS OF THE STUDY: Our aim was to investigate the effect on the excretion of Bla g 1 and Bla g 2 allergens by cockroaches exposed to sub-lethal doses of the pesticides, boric acid and hydramethylnon gel. METHODS: German cockroaches in separate colonies were fed either boric acid or hydramethylnon gel at concentrations of 0.2, 0.1 and 0.01% in their water supply over a 2 week period. Ten colonies were exposed to each treatment concentration. Bla g 1 and Bla g 2 in fecal pellets were measured by ELISA. RESULTS: Cockroaches exposed to boric acid excreted fecal pellets with significantly higher concentrations of Bla g 2 (35,400 U/g) than did controls (12,700 U/g) (P = 0.001). Bla g 1 concentrations were not significantly different. There was no difference in either Bla g 1 or Bla g 2 concentrations between cockroaches that ingested hydramethylnon gel and those in the controls colonies. CONCLUSIONS: The application of boric acid, a common pesticide, appears to paradoxically increase the production of Bla g 2, a major allergen, by the surviving cockroaches. This may have important implications in avoidance strategies.

Animals↗

Task-level control of rapid wall following in the American cockroach.

The American cockroach, Periplaneta americana, is reported to follow walls at a rate of up to 25 turns s(-1). During high-speed wall following, a cockroach holds its antenna relatively still at the base while the flagellum bends in response to upcoming protrusions. We present a simple mechanosensory model for the task-level dynamics of wall following. In the model a torsional, mass-damper system describes the cockroach's turning dynamics, and a simplified antenna measures distance from the cockroach's centerline to a wall. The model predicts that stabilizing neural feedback requires both proportional feedback (difference between the actual and desired distance to wall) and derivative feedback (velocity of wall convergence) information from the antenna. To test this prediction, we fit a closed-loop proportional-derivative control model to trials in which blinded cockroaches encountered an angled wall (30 degrees or 45 degrees ) while running. We used the average state of the cockroach in each of its first four strides after first contacting the angled wall to predict the state in each subsequent stride. Nonlinear statistical regression provided best-fit model parameters. We rejected the hypothesis that proportional feedback alone was sufficient. A derivative (velocity) feedback term in the control model was necessary for stability.

Animals↗

Dust mite, cockroach, cat, and dog allergen concentrations in homes of asthmatic children in the northeastern United States: impact of socioeconomic factors and population density.

Home exposures to aeroallergens are an important environmental factor in allergic sensitization and in the development and exacerbation of asthma. We assessed variations in home concentrations of dust mite, cockroach, cat, and dog allergens in dust collected in the main living areas of asthmatics' homes by family income, mother's education, dwelling type, population density, household population density, and ethnicity in Connecticut and south-central Massachusetts. Dust samples were collected at the time of home interview in 999 homes as part of an ongoing longitudinal birth cohort study of 1,002 infants and their asthmatic siblings. The analysis employed lower and upper cut points for group 1 dust mite (> or = 2.0 microg/g and > or = 10 microg/g), cockroach (> or = 1.0 U/g and > or = 4.0 U/g), cat (> or = 1.0 microg/g and > or = 8.0 ug/g), and dog (> or = 2.0 microg/g and > or = 10.0 microg/g) allergens. Subject residences were geocoded to assess population density from the U.S. Census, and multiple logistic regression was used to control for confounding. The portion of homes at the lower cut point for dust mite, cockroach, cat, and dog allergens were 46.9%, 24.9%, 42.2%, and 35.6%, respectively; the upper cut point for each of the allergens was reached in 22.4%, 13.4%, 21.0%, and 22.9% of the homes, respectively. In all, 86.0% of the homes had at least one allergen at the lower cut point, and 58.0% had at least one allergen at the upper cut point. Forty-nine percent of the homes had two or more allergens at the lower cut point, and 19.7% had two or more allergens at the upper cut point. Higher education of the mother, higher household income, living in a single-family home in a less densely populated area with fewer people per room, and being a white household were associated with elevated dust mite, cat, and dog allergens and low cockroach allergen. In contrast, low income, living in a multifamily home in a high population density area with a higher occupancy rate per room, and being a Hispanic or black household were associated with elevated cockroach allergens and low concentrations of dust mite, cat, and dog allergens. Although the presence of an individual allergen is more likely associated with one or more socioeconomic or ethnic factors, most homes typically have multiple allergen burdens in excess of concentrations thought to be associated with sensitization and exacerbation of asthma. Mite and cockroach allergens have distinct and opposite associations with socioeconomic factors and population density.

Adolescent↗

There are more asthmatics in homes with high cockroach infestation.

Although asthma has been commonly associated with sensitivity to cockroaches, a clear causal relationship between asthma, allergy to cockroaches and exposure levels has not been extensively investigated. The objective of the present study was to determine whether asthma occurs more frequently in children living in homes with high cockroach infestation. The intensity of household infestation was assessed by the number of dead insects after professional pesticide application. Children living in these houses in the metropolitan area of Recife, PE, were diagnosed as having asthma by means of a questionnaire based on the ISAAC study. All children had physician-diagnosed asthma and at least one acute exacerbation in the past year. Children of both sexes aged 4 to 12 years who had been living in the households for more than 2 years participated in this transverse study and had a good socioeconomic status. In the 172 houses studied, 79 children were considered to have been exposed to cockroaches and 93 not to have been exposed. Children living in residences with more than 5 dead cockroaches after pesticide application were considered to be at high infestation exposure. Asthma was diagnosed by the questionnaire in 31.6% (25/79) of the exposed group and in 11.8% (11/93) of the non-exposed group (P = 0.001), with a prevalence ratio of 3.45 (95%CI, 1.48-8.20). The present results indicate that exposure to cockroaches was significantly associated with asthma among the children studied and can be considered a risk factor for the disease. Blattella germanica and Periplaneta americana were the species found in 96% of the infested houses.

Allergens↗

Relationship between the para-homologous sodium channel point mutation (g --> c at nucleotide 2979) and knockdown resistance in the German cockroach using multiplex polymerase chain reaction to discern genotype.

Extensive use of pyrethroid insecticides for urban pest control has led to widespread pyrethroid resistance in the German cockroach. A mutation at nucleotide position 2979 (G to C, causing a leucine to phenylalanine change) in the S6 transmembrane segment of domain II of the para-homologous voltage-gated sodium channel has been previously identified in knockdown-resistant cockroaches and demonstrated by site-directed mutagenesis to reduce channel sensitivity to pyrethroids. In a recent survey, 83% of pyrethroid-resistant German cockroach populations were found to possess this mutation. A German cockroach strain with a low incidence of the L993F mutation was subjected to selection pressure with cypermethrin and subsequently evaluated over several generations for the knockdown resistance phenotype. Correspondingly, we determined the genotype of individual cockroaches of each population at the 2979 position of the para-homologous gene. Genotype was discerned by development of a polymerase chain reaction method that employed a mismatched primer-template set. A direct relationship was observed between mean knockdown time and the presence of the kdr mutation. Furthermore, individuals homozygous for the kdr mutation exhibited a significantly higher mean knockdown time than heterozygotes or wildtype cockroaches. This is the first report demonstrating the progressive expression of the kdr allele in response to insecticide selection pressure.

Animals↗

Classical olfactory conditioning in the cockroach Periplaneta americana.

We established a classical conditioning procedure for the cockroach, Periplaneta americana, by which odors were associated with reward or punishment. Cockroaches underwent differential conditioning trials in which peppermint odor was associated with sucrose solution and vanilla odor was associated with saline solution. Odor preference of cockroaches was tested by allowing them to choose between peppermint and vanilla sources. Cockroaches that had undergone one set of differential conditioning trials exhibited a significantly greater preference for peppermint odor than did untrained cockroaches. Memory formed by three sets of differential conditioning trials, with an inter-trial interval of 5 min, was retained at least 4 days after conditioning. This conditioning procedure was effective even for cockroaches that had been harnessed in plastic tubes. This study shows, for the first time in hemimetaborous insects, that both freely moving and harnessed insects are capable of forming olfactory memory by classical conditioning procedure. This procedure may be useful for future electrophysiological and pharmacological studies aimed at elucidation of neural mechanisms underlying olfactory learning and memory.

Animals↗

[Prevalence of allergy to cockroaches in the African intertropical zone. Review of the literature].

The epidemiology of environmental allergens and their role in respiratory pathology remains poorly understood in sub-Sahara Africa. The aim of this work was to measure the frequency of sensitivity to cockroach allergens of subjects with chronic respiratory affections in the Ivory Coast. We recruited consecutively 140 patients, adults and infants, who had asthma, rhinitis or sinusitis over a period of 20 months, in a hospital environment. The patients were prepared by a clinical questionnaire on atopy (personal and familial antecedents), systemic prick tests for common environmental allergens (cockroaches, mites, moulds). Our results indicated that the mean age of the children was 8 years and that of the adults 26 years (with extremes of 3 and 53 years). The proportion of patients with positive prick tests to cockroaches was 30.7% (43 cases). In asthmatics it was 16.5%. When asthma was associated with an ORL focus, 41.9% was found and in isolated ORL pathology 19.5%. Existence of familial atopy was found in 72% of cases. Discomfort from domestic dust was shown on questioning by 88.4% of cases. In 81.4% of cases positivity of the prick test to cockroaches was accompanied by a positive reaction to mites. Those who were only sensitive to cockroaches were less than 10%. Types II and III asthma were 2/3 in the asthmatic patients. In conclusion, the cockroaches were in the second rank of pneumoallergens that are implicated in sensitization and in the perpetuation of allergic respiratory symptoms, after the mites. These two factors were often associated in our patients and are consequently seen with a strong allergenic potential that is exercised by the interior environment.

Adult↗

Cockroach surveys in 14 provinces of Thailand.

Cockroach surveys using sticky traps were conducted in urban areas of 14 Thailand provinces. At least 30 houses in each province were randomly sampled for cockroaches. Each house was trapped in three areas: kitchen, bedroom and outside. A total of 2,648 cockroaches was caught by 550 out of 1,542 traps (35.7%), from 337 of the 514 houses (65.6%). Overall, relative density ranged from 2.6 to 9.1 with an average of 5.2 cockroaches/house. On the average, 47.7% of the cockroaches were caught in the kitchen, 24.4% and 27.9% were caught in the bedroom and outside of dwellings, respectively. There were 10 species of cockroaches caught from the 14 provinces: Periplaneta americana (60.9%), Periplaneta brunnea (15.4%), Neostylopyga rhombiofolia (9.6%), Periplaneta australasiae (9.2%), Pycnoscelis surinamensis (3.3%), Blatella germanica (0.6%), Periplaneta fuliginosa (0.5%), Supella longipalpa (0.3%), Blatella lituricollis (0.15%) and Nauphoeta cinerea (0.05%), belonging to six genera. According to the surveys in this study, Periplaneta americana and Periplaneta brunnea were the most abundant cockroach species in urban Thailand, whereas the kitchen was the major habitat.

Animals↗

[Mother and two siblings with cockroach asthma].

We report 2 siblings, an 11 year-old girl and a 10 year-old boy, with cockroach asthma who developed the symptoms in May and October, 1999, respectively. Both children were considered as psychogenic asthma because of poor familial environment and late onset. Their mother also had asthmatic attacks since September, 2001. It became clear in the detailed clinical history that their rooms had not been cleaned up at all for a long period, and a lot of cockroaches had lived in the house. A significantly high titer of cockroach specific IgE-antibody (CAP-RAST) was detected in all three patients, and cockroach was considered as the main allergen of asthma in these patients. Although many cases with cockroach allergy including asthma have been reported in United States, it has not been recognized well in Japan yet. We would like to emphasize that cockroach should be kept in one' s mind as an important allergen of asthma.

Allergens↗

A comparative study of prevalence of skin hypersensitivity to cockroach and house dust antigens.

Allergy skin tests with cockroach antigen along with various common inhalant allergens were performed on 222 atopic and on 63 non-atopic subjects. The most prevalent allergen producing a positive skin test was house dust antigen with a positive response of 72%, 78% and 57% in atopic adults, atopic children and non-atopic children, respectively. The next prevalent positive skin test was to cockroach antigen with 50%, 60% and 27%, respectively, of the three groups tested. The differences between positive cockroach hypersensitivity and house dust hypersensitivity in all three groups tested were statistically significant. Next in order of prevalence of positive skin test to common inhalants were western weeds, ragweeds and cats. Incidence of cockroach hypersensitivity was 58% among asthmatic adults and 69% among asthmatic children. The results indicate that cockroach hypersensitivity is highly prevalent and that cockroach antigen is an independent agent from house dust as a cause of immediate hypersensitivity reaction.

Adolescent↗

[Cockroach allergy: a study of its prevalence using skin tests with commercial extracts].

Cockroaches have been increasingly recognized as an important source of indoor allergens. In this study we assessed the prevalence of cockroach sensitization among an outpatient population observed at our Department (155 patients with a mean age of 29 +/- 12 years), based on skin "prick" tests with four commercial cockroach extracts along with a common battery of standardized inhalant allergens. We found a positive wheal to at least one of these four extracts in 27 patients: 26 (96.2%) to Blatta orientalis, 10 (37%) both to Blatella germanica and 1 (3.7%) exclusively to Blatella germanica, with no significant concordance between them. We also observed in patients with cockroach positive skin "prick" test an association with atopy (p < 0.001) and with cutaneous reactivity to other indoor allergens, namely house dust mites (p = 0.02), danders (p = 0.01) and fungi (p = 0.01). These data confirm the higher risk of cockroach sensitization among the atopic population sensitized to indoor allergens. However, the heterogeneity of the positive cutaneous responses obtained in this study, possibly reflecting the incomplete standardization of cockroach extracts, questions the real prevalence and clinical significance of this particular sensitization.

Adolescent↗

Octopamine enhances phagocytosis in cockroach hemocytes: involvement of inositol trisphosphate.

Octopamine and 5-hydroxytryptamine (5-HT) were previously shown to affect phagocytosis in cockroach hemocytes through unidentified receptor-mediated events. In the present study, we examined the ability of 5-HT and octopamine to enhance inositol trisphosphate (IP3) production using hemocyte membranes of the American cockroach, Periplaneta americana. Octopamine enhanced IP3 production with a maximal peak at 100 nM. Similarly, 5-HT enhanced IP3 production with a maximal effect at 10 nM. The effects of 5-HT and octopamine are not additive, suggesting that both are working through the same receptor. Phentolamine, a general octopamine antagonist, blocked the effects of octopamine and 5-HT, while a mammalian 5-HT2 antagonist that blocks 5-HT-sensitive receptors in insect peripheral tissue, ketanserin, did not. A pharmacological profile indicates that the receptor is similar to an octopamine1-type. Octopamine at 1 microM increased phagocytosis in cockroach hemocytes exposed to Staphylococcus aureus in vitro, and this effect was mimicked by IP3 (10 microM). The octopamine-treated hemocytes were shown to increase IP3 production in the latter stage of phagocytosis. Adult cockroaches exposed to an LD50 dose of S. aureus in conjunction with either 0.1 mM octopamine or the octopamine1 agonist, clonidine, had higher survival rates compared to saline-treated cockroaches. Correspondingly, the octopamine1 antagonist, chlorpromazine, partially blocked the octopamine-mediated increase in cockroach survival.

Analysis of Variance↗

Olfactory discrimination of structurally similar alcohols by cockroaches.

The capability of the cockroach Periplaneta americana to discriminate odors of structurally similar aliphatic alcohols was studied by using an operant conditioning paradigm. Cockroaches were trained to discriminate three odors: one odor associated with sucrose solution (reward) and two odors associated with NaCl solution (non-reward). After training, their odor preferences were tested by counting the number of visits to each odor source. We tested the capability of cockroaches to discriminate (1) three normal aliphatic alcohols with different numbers of carbon (1-pentanol, 1-hexanol and 1-octanol), (2) three C6 aliphatic alcohols (1-hexanol, 2-hexanol and trans-2-hexen-1-ol), (3) binary mixtures of two of these three alcohols and their components, and (4) 1-hexanol solution of three different concentrations (1, 10 and 100 micro g micro l(-1)). Cockroaches exhibited higher preferences for the odors associated with reward in these tests, and we therefore conclude that cockroaches can discriminate these odors. However, discrimination of 1-hexanol and trans-2-hexen-1-ol and their binary mixture was imperfect, in that some statistical tests suggested significant level of discrimination but other tests did not. In addition, the cockroaches learned to associate a 1-hexanol solution of the highest or lowest concentration with sucrose reward but failed to learn to associate 1-hexanol of an intermediate concentration with reward.

1-Octanol↗

The antennal system and cockroach evasive behavior. II. Stimulus identification and localization are separable antennal functions.

Cockroaches ( Periplaneta americana) orient their antennae toward moving objects based on visual cues. Presumably, this allows exploration of novel objects by the antennal flagellum. We used videographic and electrophysiological methods to determine if receptors on the flagellum are essential for triggering escape, or if they enable cockroaches to discriminate threatening from non-threatening objects that are encountered. When a flagellum was removed, and replaced with a plastic fiber, deflection of a "prosthetic flagellum" still activated the descending mechanosensory interneurons associated with escape and produced typical escape responses. However, escape was essentially eliminated by constraining the movement of the scape and pedicel at the antennal base. When cockroaches approached and briefly explored the surface of a spider or another cockroach with the flagellum, they produced escape significantly more often in response to subsequent controlled contact from a spider than from a cockroach. This discrimination did not depend on visual or wind-sensory input, but required flagellar palpation of the surface. The crucial sensory cues appear to involve texture rather than surface chemicals. These results indicate that cockroaches acquire basic information on stimulus identity during exploration of surfaces with flagellar receptors, but that basal receptors are triggers for escape behavior.

Animals↗

German cockroach proteases regulate matrix metalloproteinase-9 in human bronchial epithelial cells.

BACKGROUND: Matrix metalloproteinases (MMPs) digest extracellular matrix proteins and may play a role in the pathogenesis of bronchial asthma. MMP-9 levels are increased in the bronchoalveolar lavage fluid and sputum of asthmatics compared with that of controls. As exposure to cockroaches is an environmental risk factor for asthma, we sought to investigate the role of German cockroach fecal remnants (frass) on MMP-9 expression. METHODS: Human bronchial epithelial cells (16HBE14o-) and primary normal human bronchial epithelial cells were treated with cockroach frass in the absence or presence of tumor necrosis factor (TNF)alpha. MMP-9 mRNA, protein levels and pro-MMP-9 activity were determined using real-time polymerase chain reaction (PCR), enzyme-linked immunosorbent assay (ELISA) and zymogram assays. Pretreatment of frass with aprotinin abolished protease activity. PD98059, a chemical inhibitor of extracellular signal regulated kinase (ERK), and SLIGKV, an activator of protease-activated receptor (PAR)-2 were also used. AP-1DNA binding was determined by electrophoretic mobility shift assay (EMSA) and ERK phosphorylation by Western blot analysis. RESULTS: Cockroach frass augmented TNFalpha-mediated MMP-9 mRNA and protein expression by a mechanism dependent on active serine proteases within frass and not on endogenous endotoxin. Frass increased ERK phosphorylation, and chemical inhibition of ERK attenuated cockroaches' effects on MMP-9. Serine proteases are known to activate the PAR-2 receptor. We found that selective activation of PAR-2 using the peptide SLIGKV augmented TNFalpha-induced MMP-9 protein levels and increased ERK phosphorylation. Frass and SLIGKV each increased AP-1 translocation and DNA binding. CONCLUSIONS: These data suggest that German cockroach frass contains active serine proteases which augment TNFalpha-induced MMP-9 expression by a mechanism involving PAR-2, ERK and AP-1.

Animals↗