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1.
Sci China Life Sci ; 2024 Mar 22.
Article in English | MEDLINE | ID: mdl-38523236

ABSTRACT

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.

2.
Parasit Vectors ; 16(1): 382, 2023 Oct 25.
Article in English | MEDLINE | ID: mdl-37880803

ABSTRACT

BACKGROUND: Aedes albopictus is an invasive vector of serious Aedes-borne diseases of global concern. Habitat management remains a critical factor for establishing a cost-effective systematic strategy for sustainable vector control. However, the community-based characteristics of Ae. albopictus habitats in complex urbanization ecosystems are still not well understood. METHODS: A large-scale investigation of aquatic habitats, involving 12 sites selected as representative of four land use categories at three urbanization levels, was performed in Guangzhou, China during 2015-2017. The characteristics and dynamics of these Ae. albopictus habitats were assessed using habitat-type composition, habitat preference, diversity indexes and the Route index (RI), and the temporal patterns of these indexes were evaluated by locally weighted scatterplot smoothing models. The associations of RI with urbanization levels, land use categories and climatic variables were inferred using generalized additive mixed models. RESULTS: A total of 1994 potential habitats and 474 Ae. albopictus-positive habitats were inspected. The majority of these habitats were container-type habitats, with Ae. albopictus showing a particularly higher habitat preference for plastic containers, metal containers and ceramic vessels. Unexpectedly, some non-container-type habitats, especially ornamental ponds and surface water, were found to have fairly high Ae. albopictus positivity rates. Regarding habitats, the land use category residential and rural in Jiangpu (Conghua District, Guangzhou) had the highest number of Ae. albopictus habitats with the highest positive rates. The type diversity of total habitats (H-total) showed a quick increase from February to April and peaked in April, while the H-total of positive habitats (H-positive) and RIs peaked in May. RIs mainly increased with the monthly average daily mean temperature and monthly cumulative rainfall. We also observed the accumulation of diapause eggs in the winter and diapause termination in the following March. CONCLUSIONS: Ecological heterogeneity of habitat preferences of Ae. albopictus was demonstrated in four land use categories at three urbanization levels. The results reveal diversified habitat-type compositions and significant seasonal variations, indicating an ongoing adaptation of Ae. albopictus to the urbanization ecosystem. H-positivity and RIs were inferred as affected by climatic variables and diapause behavior of Ae. albopictus, suggesting that an effective control of overwintering diapause eggs is crucial. Our findings lay a foundation for establishing a stratified systematic management strategy of Ae. albopictus habitats in cities that is expected to complement and improve community-based interventions and sustainable vector management.


Subject(s)
Aedes , Ecosystem , Animals , Urbanization , Mosquito Vectors , Ovum , Larva
3.
Am J Case Rep ; 22: e933322, 2021 Sep 24.
Article in English | MEDLINE | ID: mdl-34556624

ABSTRACT

BACKGROUND Carbon monoxide poisoning is a common reason for Emergency Department admissions worldwide. The symptoms of carbon monoxide poisoning vary from headache and dizziness to severe neuropsychological and cardiac impairment. However, psoas major and iliopsoas hematomas are a rare complication of carbon monoxide poisoning. CASE REPORT A 46-year-old man with carbon monoxide poisoning, after he had been exposed to burning coal without proper ventilation, presented with right low back pain on day 7 after onset. After 2 days, ecchymosis of the right flank occurred, and his hemoglobin concentration gradually decreased. Psoas major and iliopsoas hematomas were shown on computed tomography (CT). The hematomas were successfully treated with transfusions and physical therapy. Owing to the absence of skeletal muscle compartment syndrome, surgical decompression was unnecessary. The patient did not receive anticoagulant therapy during his hospitalization. CONCLUSIONS The direct toxicity of carbon monoxide on the muscles and body weight-induced muscle compression caused skeletal muscle ischemia and necrosis in our patient. The risk of rhabdomyolysis and coagulation abnormality was elevated. Finally, intramuscular hemorrhages occurred in our patient. When a patient has back pain and decreased hemoglobin levels, clinicians should consider the possibility of psoas major and iliopsoas hematomas, and the administration of anticoagulation should be used with caution after admission.


Subject(s)
Carbon Monoxide Poisoning , Muscular Diseases , Anticoagulants/therapeutic use , Hematoma/chemically induced , Humans , Male , Middle Aged , Psoas Muscles/diagnostic imaging
4.
J Proteome Res ; 20(2): 1217-1228, 2021 02 05.
Article in English | MEDLINE | ID: mdl-33166158

ABSTRACT

As a model hemimetabolous insect species and an invasive urban pest that is globally distributed, the American cockroach, Periplaneta americana, is of great interest in both basic and applied research. Previous studies on P. americana neuropeptide identification have been based on biochemical isolation and molecular cloning. In the present study, an integrated approach of genomics- and peptidomics-based discovery was performed for neuropeptide identification in this insect species. First, 67 conserved neuropeptide or neurohormone precursor genes were predicted via an in silico analysis of the P. americana genome and transcriptome. Using a large-scale peptidomic analysis of peptide extracts from four different tissues (the central nervous system, corpora cardiac and corpora allata complex, midgut, and male accessory gland), 35 conserved (predicted) neuropeptides and a potential (novel) neuropeptide were then identified. Subsequent experiments revealed the tissue distribution, sex difference, and developmental patterns of two conserved neuropeptides (allatostatin B and short neuropeptide F) and a novel neuropeptide (PaOGS36577). Our study shows a comprehensive neuropeptidome and detailed spatiotemporal distribution patterns, providing a solid basis for future functional studies of neuropeptides in the American cockroach (data are available via ProteomeXchange with identifier PXD021660).


Subject(s)
Neuropeptides , Periplaneta , Amino Acid Sequence , Animals , Female , Genomics , Male , Neuropeptides/genetics , Peptides/genetics , Periplaneta/genetics
5.
Development ; 147(20)2020 10 23.
Article in English | MEDLINE | ID: mdl-33097549

ABSTRACT

Vitellogenesis, including vitellogenin (Vg) production in the fat body and Vg uptake by maturing oocytes, is of great importance for the successful reproduction of adult females. The endocrinal and nutritional regulation of vitellogenesis differs distinctly in insects. Here, the complex crosstalk between juvenile hormone (JH) and the two nutrient sensors insulin/IGF signaling (IIS) and target of rapamycin complex1 (TORC1), was investigated to elucidate the molecular mechanisms of vitellogenesis regulation in the American cockroach, Periplaneta americana Our data showed that a block of JH biosynthesis or JH action arrested vitellogenesis, in part by inhibiting the expression of doublesex (Dsx), a key transcription factor gene involved in the sex determination cascade. Depletion of IIS or TORC1 blocked both JH biosynthesis and vitellogenesis. Importantly, the JH analog methoprene, but not bovine insulin (to restore IIS) and amino acids (to restore TORC1 activity), restored vitellogenesis in the neck-ligated (IIS-, TORC1- and JH-deficient) and rapamycin-treated (TORC1- and JH-deficient) cockroaches. Combining classic physiology with modern molecular techniques, we have demonstrated that IIS and TORC1 promote vitellogenesis, mainly via inducing JH biosynthesis in the American cockroach.


Subject(s)
Insect Proteins/metabolism , Insulin-Like Growth Factor I/metabolism , Insulin/metabolism , Juvenile Hormones/biosynthesis , Mechanistic Target of Rapamycin Complex 1/metabolism , Periplaneta/metabolism , Signal Transduction , Vitellogenesis , Animals , Female , Methoprene/pharmacology , Ovarian Follicle/metabolism , Sirolimus/pharmacology , Vitellogenins/biosynthesis
6.
Nan Fang Yi Ke Da Xue Xue Bao ; 36(10): 1423-1428, 2016 Oct 20.
Article in Chinese | MEDLINE | ID: mdl-27777210

ABSTRACT

OBJECTIVE: To observe the effect of RITA, a small molecule that targets p53, combined with temozolomide (TMZ) on proliferation, colony formation and apoptosis of human glioblastoma U87 cells and explore the underlying mechanism. METHODS: Cultured U87 cells were treated with RITA (1, 5, 10, 20 µmol/L), TMZ, or RITA+TMZ (half dose) for 24, 48 or 72 h. MTS assay were used to detect the cell proliferation, and the cell proliferation rate and inhibitory rate were calculated. The effect of combined treatments was evaluated by the q value. The expressions of p53, p21 and other apoptosis-associated genes were detected by qRT-PCR and Western blotting; cell apoptosis was assayed using flow cytometry with Annexin V/PI double staining; colony formation of the cells was detected with crystal violet staining. RESULTS: MTS assay showed that RITA at the 4 doses more potently inhibited U87 cell viability than TMZ at 72 h (P=0.000) with inhibitory rates of 25.94%-41.38% and 3.84%-8.20%, respectively. RITA combined with TMZ caused a more significant inhibition of U87 cells (29.21%-52.11%) than RITA (P<0.01) and TMZ (P=0.000) alone. At the doses above 5 µmol/L, the combined treatments with RITA+TMZ for 48 h resulted in q values exceeding 1.2 and showed an obvious synergistic effect of the drugs. Both RITA and TMZ, especially the latter, significantly increased the expressions of p53, p21, puma, and other apoptosis-associated genes to accelerate apoptosis and inhibit the growth and colony formation of U87 cells, and the effect was more obvious with a combined treatment. CONCLUSION: RITA inhibits the growth of human glioblastoma cells and enhance their sensitivity to TMZ by up-regulating p53 expression, and when combined, RITA and TMZ show a synergistic effect to cause a stronger cell inhibition.


Subject(s)
Dacarbazine/analogs & derivatives , Furans/pharmacology , Glioblastoma/drug therapy , Apoptosis , Cell Line, Tumor , Cell Proliferation/drug effects , Cell Survival , Dacarbazine/pharmacology , Humans , Temozolomide
7.
Asian Pac J Cancer Prev ; 13(7): 3123-7, 2012.
Article in English | MEDLINE | ID: mdl-22994721

ABSTRACT

OBJECTIVE: Experimental studies have suggested green tea to be a chemopreventive agent for colorectal cancer, and many studies have examined possible associations. However, the conclusions were inconsistent or even contradictory, so we performed a meta-analysis based on published case-control studies to explore if green tea is indeed a protective factor. METHODS: PubMed was searched up to May 10th, 2012 for relevant studies, and references of included studies were manually searched. Finally 13 eligible studies, involving 12,636 cases and 38,419 controls were identified. After data extraction, a meta-analysis was performed using CMA v2 software. RESULTS: The results indicated there may be a weak but not statistically significant reduced risk of colorectal cancer with high dose of green tea intake (OR=0.95, 95% CI:0.81-1.11, p=0.490.69-0.98). This protective effect was also found in all subgroups, except in American and European populations. Sensitivity analysis indicated the result to be robust. Publication bias was not detected by either funnel plot or Egger tests. CONCLUSION: The results of this meta-analysis indicate a weak lower tendency for colorectal cancer development with green tea consumption, but available epidemiologic data are insufficient to conclude that green tea may protect against colorectal cancer in humans.


Subject(s)
Camellia sinensis/chemistry , Colorectal Neoplasms/epidemiology , Plant Extracts/administration & dosage , Tea , Beverages , Case-Control Studies , Colorectal Neoplasms/prevention & control , Humans , Risk
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