Cockroach Research Articles

Study on cockroach antigen as a probable causative agent in bronchial asthma

Bronchial provocative test (BPT) with cockroach (CR) antigen was performed in 22 asthmatic subjects. Sixteen had positive reaction (CR-positive) and 6 had negative reaction (CR-negative) to CR antigen by skin test. Immediate bronchoconstrictive response was noted following the antigen inhalation in 14 of 16 CR-positive asthmatics, while none of 6 CR-negative asthmatics showed bronchospasm. Late asthmatic responses also were noted in 13 of 16 CR-positive asthmatic individuals following BPT with CR antigen. The dual asthmatic reactions in CR-positive individuals were mostly inhibited by the prior administration of cromolyn sodium. Three-fold increases in peripheral eosinophil counts were noted 24 hr following BPT with CR antigen. Results indicate that CR-induced asthmatic responses are allergen-specific and CR plays a causative role in allergic asthma in the population studied.

A new efferent pathway in the cockroach CNS.

Viene descritta una nuova via efferente della catena ganglionare diPeriplaneta americana, che origina nel 1° ganglio addominale, raggiunge i nervi cercali (NXI) ed e interrotta da sinapsi in ciascuno dei sei gangli addominali. Vengono riferiti la velocita di conduzione nei connettivi ed i tempi di trasmissione a livello dei gangli.

Advances in Twin Studies

Despite a growing consensus on the involvement of γδ T cells in allergy and other human immunological disorders, the detailed mechanisms remain hypothetical due to lack of investigative tools. Herein, we sought to develop functional assays to study the role of γδ T cells in allergy. Using an Activation-Induced Marker (AIM) assay, based on the upregulation of 4-1BB (CD137) and CD69, we were able to detect ex vivo allergen-specific responses from γδ T cells to multiple allergen extracts in human PBMCs, including mouse, cockroach (CR), house dust mite (HDM) and timothy grass (TG) allergens, which were reproducible and observed in multiple allergic cohorts. The magnitude of allergen-reactive γδ T cells differed between allergic and non-allergic cohorts with HDM and TG allergy, but not mouse or CR allergy. Further characterization showed that the γδ T cells reactive to mouse allergen were mostly the Vδ2 subset and from effector memory (Tem and Temra) compartments. Interestingly, in mouse-specific allergic donors we found differential polarized responses for γδ and ab T cells, with a Th1 and Th2 pattern, respectively. Using a complementary AIM assay for CD40L (CD154) combined with intracellular staining (ICS), we observed that Th1 polarization (INFg and TNFa) in responses to mouse extract was also common in non-allergic donors. Conversely, In the case of CR responses, Th1 polarization of Vδ2 T cells was only observed in the allergic cohort. Overall, these results suggest that allergen-specific Vδ2 T cells are potential to skew dysregulated cytokine responses in immunotherapy. In conclusion, we developed new functional assays that serve as tools for in-depth characterization and deciphering the roles of γδ T cells in allergy.

Detection of early changes in cockroach hemocytes during coagulation with 8-anilino-1-naphthalene sulfonic acid.

Gewisse Hamozyten vonBlatta orientalis L. zeigten in Gegenwart fluoreszierender 8-Anilin-1-Naphthalensulfonsaure im Lebendpraparat zytoplasmische Fluoreszenz, wahrend die Entwicklung dieser Fluoreszenz in anderen Hamozyten betrachtlich variiert und bis zu 7 min benotigt. Es besteht die Moglichkeit, mit dieser Fluoreszenzprobe Membranveranderungen in Hamatozyten zu erfassen.

A New Film on the Biology of the Cockroach

A New Film on the Biology of the Cockroach

Electron microscopy of symbiotic bacteria in developing oocytes of the American cockroach, Periplaneta americana.

Electron microscopy of symbiotic bacteria in developing oocytes of the American cockroach, Periplaneta americana.

Mechanism of the after-potential production in the giant axons of the cockroach.

Mechanism of the after-potential production in the giant axons of the cockroach.

Digestion in the Cockroach

Digestion in the Cockroach

La Terre des Merveilles . Par Jules LeClercq. Paris, Hachette. 8°.

<i>La Terre des Merveilles</i> . Par Jules LeClercq. Paris, Hachette. 8°.