Relationship between parasitism and morphology of Trichogramma (Hymenoptera: Trichogrammatidae) on Spodoptera frugiperda (Lepidoptera: Noctuidae)

In this study, 5 species of Trichogramma Westwood were evaluated for the biological control of Spodoptera frugiperda (JE Smith), concerning the physical characteristics of female Trichogramma. The results showed that Trichogramma chilonis Ishii, Trichogramma dendrolimi Matsumura, and Trichogramma ostriniae Pang et Chen exhibited high parasitism rates, emergence rates, and offspring numbers, with the highest values observed for T. ostriniae. The ovipositor length of Trichogramma japonicum Ashmead and T. dendrolimi were longer than those of other species, and the hind tibia length was the shortest in Trichogramma cacoeciae Marchal. We further evaluated relationships between the parasitism ability of Trichogramma and various morphological indexes based on Spearman's rank correlation coefficients. A positive correlation was found between the parasitism rate and hind tibia length of T. cacoeciae. In T. dendrolimi, the parasitism rate was negatively correlated with ovipositor width and positively correlated with the length-width ratio of the ovipositor. A significant positive correlation was observed between the proportion of female offspring and the mother's ovipositor length in T. japonicum. However, there were no significant correlations between morphological indexes and indexes of parasitism in T. ostriniae. Overall, the parasitic abilities of T. chilonis on S. frugiperda eggs were significantly correlated with the morphology of the female ovipositors.

[Effects of NLRP3-mediated pyroptosis on olfaction dysfunction in allergic rhinitis]

Objective: To explore the relationship between NLRP3-mediated pyroptosis and olfactory dysfunction (OD) in allergic rhinitis (AR), and to evaluate the therapeutic potential of CY-09, a selective NLRP3 inhibitor for OD. Methods: An AR mouse model was established with ovalbumin, and the olfactory function of AR mice was detected by the buried food pellet test. Mice with OD were intraperitoneally injected with CY-09 or saline. The activation of microglia and astrocytes in olfactory bulb was detected by immunohistochemistry. The expression level of pyroptosis associated protein was detected by Western blot. The level of pyroptosis associated proinflammatory factor mRNA was determined by real-time PCR. SPSS 24.0 software was used for statistical analysis. Results: After the test, ovalbumin successfully established AR mice model, in which 52.5% (21/40) of them showed OD. The number of activated microglia and astroglia in olfactory bulb tissue in OD group were more than those in non-OD group (all P<0.05). Compared with the control group, the expression of NLRP3, caspase-1 and gasdermin D (GSDMD) was significantly increased in the olfactory bulb of the OD group (all P<0.05). CY-09 could significantly reduce the level of NLRP3, caspase-1, GSDMD, IL-1β and IL-18 expression, and inhibite the activation of microglia and astrocytes in the olfactory bulb tissues (all P<0.05). Conclusion: NLRP3-mediated pyroptosis is closely related to the OD associated with AR. CY-09 could improve the olfactory function in AR mice, which may be related to blocking the NLRP3-mediated pyroptosis.

[Predictive diagnostic value of serum 25-hydroxyvitamin D3 in eosinophilic chronic rhinosinusitis with nasal polyps]

Objective: To compare the value of 25-hydroxyvitamin D3 (25-(OH)D3) with other clinical parameters in the prediction and diagnosis of eosinophilic chronic rhinosinusitis with nasal polyps (ECRSwNP). Methods: Eligible chronic rhinosinusitis with nasal polyps (CRSwNP) patients and healthy subjects in the Affiliated Hospital of Guizhou Medical University from January to April of 2021 were included for this study. The age, gender, past history and other basic characteristics of all subjects were recorded. The CRSwNP patients were classified into ECRSwNP and non-eosinophilic chronic rhinosinusitis with nasal polyps (nECRSwNP) endotypes by the percentage of tissue eosinophils. Serum 25-(OH)D3 levels measurements were performed in all subjects. Paranasal sinus CT scans, blood eosinophil counts, and determination of total immunoglobulin E (total IgE), Th1/Th2 plasma cytokines and nasal nitric oxide (nNO) levels were performed before surgery. Logistic regression analysis was used to evaluate the related factors of ECRSwNP. Receiver operating characteristic (ROC) curves was used to evaluate the predictive potential of the clinical parameters. Results: One hundred and twenty-seven CRSwNP patients and 40 healthy subjects were recruited, including 74 males and 93 females of the patients, with the age of (38.73±13.05) years. In patients with ECRSwNP, serum 25-(OH)D3 levels were significantly lower than those in nECRSwNP patients ((26.14±4.58) ng/ml vs (35.71±7.86) ng/ml, t=-8.564, P<0.01). The prevalence of asthma, prevalence of allergic rhinitis, peripheral blood eosinophil counts, total IgE levels, nNO levels and CT scores ratio for ethmoid sinus and maxillary sinus (E/M ratio) of ECRSwNP patients were significantly higher than those in nECRSwNP patients (all P<0.05). However, there was no significant difference in Th1/Th2 cytokines levels between the histological types of CRSwNP (all P>0.05). Among the predictive indicators, 25-(OH)D3 had the highest predictive value, with ROC area under curve (AUC) value of 0.882. The best cut-off point of 28.5 ng/ml for 25-(OH)D3 demonstrated a sensitivity of 0.871 and a specificity of 0.762 for ECRSwNP. Conclusion: Measurement of serum 25-(OH)D3 level may be used as an effective method to distinguish between ECRSwNP and nECRSwNP.

Protective effects of calcitonin gene-related peptide on guinea-pig cardiac anaphylaxis

Anaphylactic events occurring in cardiac tissues can result in cardiac dysfunction via vasoconstriction and arrhythmias. Calcitonin gene-related peptide (CGRP) is the most potent vasodilator and possesses anti-arrhythmic action. We examined the influence of CGRP on cardiac anaphylaxis in guinea-pigs. In the Langendorff-perfused heart of passively sensitized guinea-pigs, antigen challenge evoked a decrease in coronary flow, left ventricular pressure and its maximum first derivatives (+/-dP/dtmax) and an increased heart rate. Antigen challenge also induced atrioventricular conduction block. Treatment with CGRP (1 or 3 nM) significantly improved the recovery of cardiac function and reduced the incidence and duration of atrioventricular block without influencing the increased heart rate. Pretreatment with capsaicin caused effects similar to those of CGRP and markedly elevated the content of CGRP in coronary effluent. Ischaemic preconditioning, induced by two cycles each of 5 min global ischaemia and 5 min reperfusion, also improved cardiac function and raised the level of CGRP in coronary effluent. The protective effects of ischaemic preconditioning were abolished in the presence of the CGRP receptor antagonist CGRP8-37. Histamine release did not differ significantly during any of the interventions. The findings of the present study indicate that, in guinea-pig hearts, CGRP protects against cardiac anaphylaxis and that the cardioprotection by CGRP is independent of histamine release.

Early and delayed protection by capsaicin against reperfusion injury in rat hearts

AIM

To study early or delayed cardioprotection afforded by pretreatment with capsaicin.

METHODS

The isolated rat heart was perfused in a Langendorff model. Heart rate, coronary flow, left ventricular pressure, and its first derivative (+/- dp/dtmax) were recorded, and the calcitonin gene-related peptide-like immunoreactivity (CGRP-LI) and the release of creatine kinase (CK) were measured.

RESULTS

Capsaicin (50 mg.kg-1, s.c.) improved the recovery of cardiac function and decreased the release of CK. CK was (2.12 +/- 0.40) and (0.26 +/- 0.04) u.min-1.g-1(wet wt) for ischemia-reperfusion (I/R) and capsaicin + I/R, respectively (P < 0.05). Capsaicin treatment caused an increase in the concentration of CGRP-LI in plasma. CGRP-LI was (135 +/- 12) and (304 +/- 45) ng.L-1 for vehicle + I/R and capsaicin + I/R, respectively (P < 0.05). After pretreatment with capsaicin to deplete the sensory nerve transmitter content, the cardioprotection and the increased level of CGRP by capsaicin were abolished. A delayed protection was shown in the hearts obtained from the rats pretreated with capsaicin 24 h or 48 h before the experiments.

CONCLUSION

Pretreatment with capsaicin induces the early and delayed cardioprotection, which may be related to stimulation of CGRP release in the rat.

Protection of calcitonin gene-related peptide-mediated preconditioning against coronary endothelial dysfunction induced by reperfusion in the isolated rat heart

This study was designed to explore the protective effect of ischemic preconditioning on reperfusion-induced coronary endothelial dysfunction, with a focus on the role of calcitonin gene-related peptide (CGRP) in this effect, in the isolated perfused rat heart. Thirty minutes of global ischemia and 30 min of reperfusion significantly decreased heart rate, left ventricular pressure, and its first derivative and impaired vasodilator responses to acetylcholine. Ischemia-reperfusion did not affect vasodilator responses to sodium nitroprusside. Preconditioning induced by three cycles of 5 min of ischemia and 5 min of reperfusion produced a significant improvement in cardiac function concomitantly with an amelioration of vasodilator responses to acetylcholine. The protective effects of ischemic preconditioning were abolished by CGRP(8-37) (10(-7) M) , the selective CGRP receptor antagonist. After pretreatment with capsaicin (50 mg x kg(-1), s.c.) to deplete endogenous CGRP, the preconditioning effect was absent. Pretreatment with exogenous CGRP (5 x 10(-9) M) for 5 min induced a preconditioning-like protection. The present study suggests that the cardioprotection of ischemic preconditioning is related to the preservation of the coronary endothelial cell, and that the protective effect of preconditioning is mediated by endogenous CGRP in the isolated perfused rat heart.

Mediation of calcitonin gene-related peptide in protection of ischemic preconditioning in rat hindlimbs

AIM

To study modulation of calcitonin gene-related peptide (CGRP) in the protective effect of ischemic preconditioning on endothelial cells.

METHODS

Rat hindlmbs were subjected to ischemia for 2 h, and endothelium-dependent vasorelaxation to acetylcholine (ACh) was examined in rat hindlimbs.

RESULTS

Two hours of ischemia elicited no effect on vasoconstrictor responses to norepinephrine, but markedly impaired vasodilator responses to ACh. Ischemic preconditioning induced by 5-min aortic occlusion and 10-min blood reperfusion prevented the impairment of vasorelaxation to ACh due to long-term ischemia. The protection of ischemic preconditioning was abolished by repeated pretreatments with capsaicin to deplete CGRP. Acute application of capsaicin to evoke CGRP release or CGRP caused an ischemic preconditioning-like protection.

CONCLUSION

Capsaicin-sensitive sensory nerves are involved in the protective effect of ischemic preconditioning on endothelial cells in the rat hindlimbs, and CGRP can mimic the protective effect of ischemic preconditioning in blood vessels.

von Hippel-Lindau disease: identification of deletion mutations by pulsed-field gel electrophoresis

Von Hippel-Lindau disease (VHL) is an inherited multisystem neoplastic disorder. We prepared a 2.5-megabase (Mb) restriction map of the region surrounding the VHL gene and identified and characterized overlapping deletions in three unrelated patients affected with VHL. The smallest nested deletion (100 kb) was located within a 510-kb NruI fragment detected by 19-63'. The rearrangements detected will be useful in isolating and evaluating candidate cDNAs for the VHL gene. The detailed physical map will be useful in studying the organization and structure of genes in the VHL region.