SEARCH · Search PubMed
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.
In this study the skin test with cockroach antigen was employed to 125 allergic patients and 100 normal individuals. 36% of the allergic patients and 13% of the other group gave positive skin reaction. In 45 patients with positive skin tests to cockroach antigen sensitivity to house-dust antigen was also determined. The results of tests with these two antigens were compared.
On isolated abdominal nervous chain of the cockroach studies have been made of the responses of motoneurones of the thoracic ganglion to electrical stimulation of afferent axons of the leg nerve under normal conditions and during application of an anticholinesterase drug, GD-7. Depending on the type of stimulated axons, monosynaptic response, as well as polysynaptic phasic and tonic responses of motoneurones were recorded. A scheme of activation of motoneurones is suggested which evokes slow contractions of muscles in cockroach extremities.
It was ascertained that lysol 2% and 5% showed the most toxic effect in control of cockroaches in the contact method (23.3% and 95.5% mortality after 24 hours of exposure), and that chloramine 1%, 3% and 5% was the most effective food poison (after 19 days exposure 100% of the insects died). When injecting disinfectant into the body cavity, the cockroaches showed a ten times higher sensibility to formalin and chloramine than to lysol. The use, however, of disinfectant in the contact method (particularly lysol 2%) together with an insecticide based on propoxur, allowed to reduce its dose to a half, what gave better results than the use of an insecticide alone in a normal dose.
The neurosecretory material is found depleted in the medial neurosecretory cells in adult cockroaches poisoned with insecticide. It is, however, scanty in the neurosecretory pathway but abundant in the corpora cardiaca of these insects. The administration of toxicated haemolymph in the normal cockroach results in scanty material in medial neurosecretory cells, but the accumulation of the neurosecretory material in corpora cardiaca. The toxicated tissue extracts have also caused depletion of neurosecretory material from the medial neurosecretory cells as well as from the axonal tract and its accumulation in the corpora cardiaca. Thus effect is comparatively more pronounced by the extract from the Malpighian tubules and nerve cord than than of brain extract. Thus the effect produced by insecticide on the stimulation--secretion coupling mechanism of neurosecretion is comparable to the produced by the toxicated haemolymph and tissue extract. The possibility of involvement of the adrenergic system in regulating the action of neuroactive material on neurosecretory cells is suggested in the insects.
Studies have been made of non-specific influences of supraesophageal ganglion on the excitability of the segmental centers in the cockroach P. americana. It was shown that electrical stimulation of the mushroom bodies decreases the frequency of the background discharges which are observed in the neuropile of the central body, decreasing simultaneously the activity of motor fibers of the Vth nerve. On the contrary, stimulation of the central body increases the frequency of the spontaneous activity in motor output. It is suggested that the inhibitory influences from the mushroom bodies upon the segmental motor apparatus may spread both directly and in a stepwise fashion, i. e. via the intermediate structure of the central body. The latter is involved into the control of muscle tonus in the cockroach.
By grafting operations, interspecific eye chimeras of the cockroaches Gromphadorhina portentosa and Leucophaea maderae were produced. Mechanisms involved the development of both the compound eye and the retina-lamina projection have been studied. Most cell types composing the eyes of these cockroaches are cytologically distinguishable in the chimera; also, retinula axons forming the retina-lamina projection in the two species are of vastly different lengths. At the border between host and graft eye tissue, individual ommatidia are formed containing cells of both types. It particular, it is shown that the four cone cells can be found in any of the possible combinations of the two cell types. This shows that the cone cells within one ommatidium are not necessarily related by lineage. These results are in agreement with the hypothesis that cells within an ommatidium are determined by position rather than by a lineage mechanism. Furthermore, formation of mosaic ommatidia suggests that mechanisms governing eye formation are similar in these two species. The formation of the projection from donor retina to host lamina shows that axon elongation is not rigidly programmed, but that the axons grow until they reach a suitable target at which point connexions are made.
It has been demonstrated that all functional types of the pedicel receptors (i.e. receptors maintaining the flight in the cockroach) exhibit evident directional sensitivity. The limits of maximum sensitivity to mechanical shift of the flagellum respectively pedicel in the main bulk of the sensillae lies within 90-135 degrees. The increase in the amplitude of the shift of the flagellum increases these limits. Since in all types of the sensillae receptor cells are distributed in the pedicel rather evenly and each receptor has its own band of maximum sensitivity (which differs from that of the adjacent receptors), the shift of the flagellum to any direction results in sending to the central nervous system of a relatively constant volley of nervous impulses, which presumably maintains the activity of the neurones in wing apparatus during the flight of the cockroach.
The occurrence of salmonellae in common house-pests viz. rats, house-mice, shrews, cockroaches and ants was investigated during the period of Jan. 1976 to July 1979. Of 767 samples examined, 43 yielded different Salmonella serotypes. The isolation of salmonellae was made from 16 of 254 rats, 11 of 109 house-mice, 11 of 104 shrews, 3 of 270 cockroaches and 2 of 30 ants. The different Salmonella serotypes isolated included S. saint-paul, S. bareilly, S. newport, S. weltevreden, S. enteritidis, S. typhimurium, S. hvittingfoss, S. anatum, S. metopeni, S. waycross and S. paratyphi B. One shrew yielded three different serotypes of salmonellae, while dual infection was detected in three shrews and one rat.
Interactions of phoscarban and its "oxon" with the esterase complex of the house-fly imago and four species of synanthropic cockroaches were studied. Phoscarban and its oxon have a wide spectrum of effects on the esterase complex in cockroaches and flies. These compounds are not specific inhibitors of any of the zones of esterase activity. Their insecticide effect depends on their ability to inhibit both choline esterases, which are responsible for nervous activity, and carboxyl esterases, which are involved in the detoxication of these compounds. We studied the species specificity of the esterase complex, including individual types and fractions, to phoscarban and its oxon in the order Dictyoptera. It was especially distinct for membrane-bound and water-soluble forms of choline esterases.
The usefulness was tested of the biological insecticides containing B. thuringiensis available in the market in the eradication of cockroaches. Thuridan was the most effective out of the tested insecticides in reducing the number of the insects. Its higher activity in relation to Thuricide was evident at all tested concentrations. Males were more sensitive than females. On the other hand, no significant response of cockroaches to M-one preparation was noted, since the per cent of dying insects was only slightly higher than in the control group.
Resistance to permethrin was tested in cockroaches caught in health service institutions in various parts of Poland. The tests were carried out by the contact method as recommended by the WHO. The density of the insecticide was 20 mg/m2. The experiment was done only on male insects, calculating the values of LT50 and LT90 in insect groups caught in various localities. These values were compared with LT50 and LT90 values in sensitive insects exposed to the insecticide, and the resistance indices R50 and R90 were calculated. This made possible determination of permethrin resistance of the populations from various areas. The results showed that the sensitivity of the insects varied. Cockroaches caught in Opole, Biała Podlaska, Szczecin, Warsaw were highly resistant to permethrin, while those from Płock, Piotrków Trybunalski, Chojnów, Nowy Sacz tolerated the insecticide, and those from Jedrzejów were as sensitive as control laboratory insects.
The DNA and amino acid sequences of the membrane-spanning region of the GABA receptors of the German cockroach have been identified along with information on the nature and the specific site of mutation in the cyclodiene-resistant strains. In this resistant strain, the mutation has occurred at the most conserved, lower M2 cylinder region involving a G to T conversion, resulting in an amino acid change of alanine (GCC) residue to serine (TCC). The site, furthermore, coincides with the most conserved region of all GABA receptor subunits and the expected Cl- transporting segment constituting the innermost surface of the channel opening. The deduced sequence of the German cockroach GABA receptor differs from that of Drosophila mainly in the connecting region between M3 and M4.
The cockroach has been reported as a major allergen in inner city asthmatic patients. The retrospective chart review of 799 patients tested over a 10-year period (1981-1991) derived from a private allergy practice and a university allergy clinic is reported. Patients from both groups were divided geographically by home zip codes into inner city, suburban, or rural small town populations. Criteria for positive skin tests were wheal greater than 5 mm for prick and greater than 10 mm for intradermal tests with flare. Overall, 36.9% (295/799) of all patients surveyed were positive by either prick or intradermal skin testing. Cockroach reactivity was observed in 38.6% (95/246) of the private patients tested with 36.2% (200/553) of the university patients showing positive results. The inner city populations in both groups of patients were similar with 43.7% and 40.3% of the private and university patients, respectively, testing positive, with an overall positivity of 41% for all inner city patients. Inner city and rural small town populations for both study groups demonstrated almost identical reactivity with 41% and 43% overall positivity, respectively. Of the suburban group, 37.5% of the private patients and 28.8% of the university patients had reactive skin tests results with an overall rate of positivity of 30.1%. This rate (30.1%) is significantly less than the rate for either inner city (41.0%, P < .05) or rural small town (43.6%, P < .01) populations.(ABSTRACT TRUNCATED AT 250 WORDS)
Allergenic extracts used for immunotherapy often contain mixes of different allergens. Studies have shown that certain allergenic extracts contain enzymes that can cause a decrease in grass pollen allergenicity when mixed with grass extracts. Glycerin and buffered saline with phenol (BSP) extracts containing Helminthosporium interseminatum, D. farinae, and cockroach were mixed with perennial ryegrass extracts and analyzed 7, 30, 60, and 90 days after mixing to determine the mixing effect of these extracts on the ryegrass pollen potency. Analysis was performed using RAST inhibition, SDS-PAGE and, to determine biologic potency, a quantitative intradermal skin test technique. All tests showed significant decreases in ryegrass potency when mixed with Helminthosporium and cockroach. This decrease was not seen with the D. farinae mix. Glycerin seemed to have some protective effect. Even in the situation showing the most decrease in ryegrass potency (Helminthosporium mixed with ryegrass in a BSP extract), the resulting extract still contained an estimated biologic potency of 10,000 AU/mL. This may explain why such mixes, which have been used clinically for many years, appear to give adequate therapeutic results. The study also suggest that clinicians may be well advised not to mix grass pollen extracts with extracts that may contain proteolytic enzymes.
The AA have isolated a new serovar of Genus Salmonella S.V 13.22:r:-, from a cockroach Periplaneta Americana, captured near the municipal slaughterhouse of Messina and near the Faculty of Veterinary Science. This fifth original report fift in the vast subject of the environmental pollution, where the cockroaches, as widely documented, unwind a primary importance part as spreader of Salmonella, too.
In the order to know both the sensitivity and positivity between the allergenic extracts of cockroach (C), house dust (HDJ, and Dermatophagoides pteronyssinus (Dpt) we made a transversal study in 783 allergic patients who underwent intradermal skin tests with the antigens of C, HD and Dpt. Allergic asthma and rhinitis were the more frequent diagnosis. There was no significative difference between the sensitivity to C and HD (p = 0.1),-women were more sensitive to C than to HD (p < 0.05). We found a greater sensitivity to Dpt than C and HD (p < 001). There were more positive patients to C than to HD (p = 0.01) and although we observed more positive patients to Dpt than to C (p = 0.01) this difference was not significative for women (p = 0.05). We can conclude than cockroach, as an allergic source, has similar importance that house dust mite, and it is inadequate its substitution with house dust extracts in skin tests screening.
A study was carried out to determine the distribution of cockroaches in two different housing areas with central sewerage or individual septic tanks in an urban area in Kuala Lumpur, Malaysia. Six species of cockroaches were present and of these Periplaneta americana and Periplaneta brunnea were found in greater abundance. Seventeen species of bacteria were isolated and of these Escherichia coli and Klebsiella p. pneumoniae were isolated in greatest numbers. Control measures carried out using lambda cyhalothrin showed that there was no significant difference between treated and control sites.
All kinds of arthropoda can find a suitable environment to grow and spread in this country because of its mild and subtropical climate. Arthropods are harmful to men, animals and plants in many ways. The most important role the arthropods play is in carrying germs and parasites. Cockroaches are widely spread in Turkey, they transmit bacteria, viruses, protozoa and helminths mechanically and biologically. Because of their close contact with human beings, these insects encouraged us to make parasitological investigations. In the hindgut of cockroaches we found three nemethod species; Suifunema caudelli, Galebia aegyptiaca, and Hammerschmidtiella diesingi.