Integrated analysis of single-cell chromatin state and transcriptome identified common vulnerability despite glioblastoma heterogeneity.

In 2021, the World Health Organization reclassified glioblastoma, the most common form of adult brain cancer, into isocitrate dehydrogenase (IDH)-wild-type glioblastomas and grade IV IDH mutant (G4 IDHm) astrocytomas. For both tumor types, intratumoral heterogeneity is a key contributor to therapeutic failure. To better define this heterogeneity, genome-wide chromatin accessibility and transcription profiles of clinical samples of glioblastomas and G4 IDHm astrocytomas were analyzed at single-cell resolution. These profiles afforded resolution of intratumoral genetic heterogeneity, including delineation of cell-to-cell variations in distinct cell states, focal gene amplifications, as well as extrachromosomal circular DNAs. Despite differences in IDH mutation status and significant intratumoral heterogeneity, the profiled tumor cells shared a common chromatin structure defined by open regions enriched for nuclear factor 1 transcription factors (NFIA and NFIB). Silencing of NFIA or NFIB suppressed in vitro and in vivo growths of patient-derived glioblastomas and G4 IDHm astrocytoma models. These findings suggest that despite distinct genotypes and cell states, glioblastoma/G4 astrocytoma cells share dependency on core transcriptional programs, yielding an attractive platform for addressing therapeutic challenges associated with intratumoral heterogeneity.

Old trees bloom new flowers, lysosome targeted near-infrared fluorescent probe for ratiometric sensing of hypobromous acid in vitro and in vivo based on Nile red skeleton.

Hypobromous acid (HOBr), one of the significant reactive oxygen species (ROS) that acts as an important role in human immune system, however the increasing level of HOBr in human body can cause the disorder of eosinophils (EPO), leading to oxidative stress in organelles, and further causing a series of diseases. In this study, a ratiometric fluorescent probe DMBP based on Nile red skeleton was developed to detect HOBr specifically by the electrophilic substitution with HOBr. DMBP emits near-infrared (NIR) fluorescence at 653 nm, after reacting with HOBr, the emission wavelength of DMBP shifted blue and a new peak appeared at 520 nm, realizing a ratiometric examination of HOBr with a limit of detection of 89.00 nM. Based on its sensitive and specific response to HOBr, DMBP was applied in the visual imaging of HOBr in HepG2 cells and zebrafish. Foremost, probe DMBP has excellent lysosome targeting ability and NIR emission reduced the background interference of biological tissues, providing a potential analytical tool to further investigate the role of HOBr in lysosome.

Changes in liver and kidney function, red blood cell count and hemoglobin levels 1 day after ultrasound-guided percutaneous microwave ablation for uterine fibroids.

OBJECTIVE: To investigate the changes in liver and kidney function, red blood cell (RBC) count and hemoglobin (HGB) levels in patients undergoing ultrasound-guided percutaneous microwave ablation (UPMWA) for uterine fibroids on postoperative day 1. METHODS: The changes in liver and kidney function, RBC count and HGB levels in 181 patients who underwent selective UPMWA in the Second Affiliated Hospital of Shantou University Medical College, China, between August 2017 and January 2023 were retrospectively analyzed. RESULTS: All patients underwent UPMWA for uterine fibroids; 179 patients had multiple uterine fibroids and 2 patients had single uterine fibroids. The maximum fibroid diameter ranged from 18 to 140 mm, with an average of 68.3 mm. Ultrasound imaging was used to confirm that the blood flow signal within the mass had disappeared in all patients, indicating that the ablation was effective. Within 24 h, compared with before UPMWA, levels of total bilirubin, direct bilirubin, indirect bilirubin and aspartate aminotransferase had significantly increased (p < 0.01), whereas levels of total protein, albumin, globulin, alanine aminotransferase, creatinine and urea had significantly decreased (p < 0.01). Acute kidney injury (AKI) occurred in 1 of the 181 patients. The RBC count and HGB levels decreased significantly after UPMWA (p < 0.01). CONCLUSION: Ultrasound-guided percutaneous microwave ablation for uterine fibroids can impose a higher detoxification load on the liver and cause thermal damage to and the destruction of RBCs within local circulation, potentially leading to AKI. Protein levels significantly decreased after UPMWA. Therefore, perioperative organ function protection measures and treatment should be actively integrated into clinical practice to improve prognosis and enhance recovery.

Carnosol alleviates sepsis-induced pulmonary endothelial barrier dysfunction by targeting nuclear factor erythroid2-related factor 2/sirtuin-3 signaling pathway to attenuate oxidative damage.

Excessive reactive oxygen species production during acute lung injury (ALI) will aggravate the inflammatory process and endothelial barrier dysfunction. Carnosol is a natural phenolic diterpene with antioxidant and anti-inflammatory properties, but its role in treating sepsis-induced ALI remains unclear. This study aims to explore the protective effects and underlying mechanisms of carnosol in sepsis-induced ALI. C57BL/6 mouse were preconditioned with carnosol for 1 h, then the model of lipopolysaccharide (LPS)-induced sepsis was established. The degree of pulmonary edema, oxidative stress, and inflammation were detected. Endothelial barrier function was evaluated by apoptosis and cell junctions. In vitro, Mito Tracker Green probe, JC-1 staining, and MitoSOX staining were conducted to investigate the effect of carnosol on mitochondria. Finally, we investigated the role of nuclear factor-erythroid 2-related factor (Nrf2)/sirtuin-3 (SIRT3) in carnosol against ALI. Carnosol alleviated LPS-induced pulmonary oxidative stress and inflammation by inhibiting excess mitochondrial reactive oxygen species production and maintaining mitochondrial homeostasis. Furthermore, carnosol also attenuated LPS-induced endothelial cell barrier damage by reducing vascular endothelial cell apoptosis and restoring occludin, ZO-1, and vascular endothelial-Cadherin expression in vitro and in vivo. In addition, carnosol increased Nrf2 nuclear translocation to promote SIRT3 expression. The protective effects of carnosol on ALI were largely abolished by inhibition of Nrf2/SIRT3. Our study has provided the first evidence that the Nrf2/SIRT3 pathway is a protective target of the endothelial barrier in ALI, and carnosol can serve as a potential therapeutic candidate for ALI by utilizing its ability to target this pathway.

MRI-based machine learning models predict the malignant biological behavior of meningioma.

BACKGROUND: The WHO grade and Ki-67 index are independent indices used to evaluate the malignant biological behavior of meningioma. This study aims to develop MRI-based machine learning models to predict the malignant biological behavior of meningioma from the perspective of the WHO grade, Ki-67 index, and their combination. METHODS: This multicenter, retrospective study included 313 meningioma patients, of which 70 were classified as high-grade (WHO II/III) and 243 as low-grade (WHO I). The Ki-67 expression was classified into low-expression (n = 216) and high-expression (n = 97) groups with a threshold of 5%. Among them, there were 128 patients with malignant biological behavior whose WHO grade or Ki-67 index increased either or both. Data from Center A and B are were utilized for model development, while data from Center C and D were used for external validation. Radiomic features were extracted from the maximum cross-sectional area (2D) region of Interest (ROI) and the whole tumor volume (3D) ROI using different paraments from the T1, T2-weighted, and T1 contrast-enhanced sequences (T1CE), followed by five independent feature selections and eight classifiers. 240 prediction models were constructed to predict the WHO grade, Ki-67 index and their combination respectively. Models were evaluated by cross-validation in training set (n = 224). Suitable models were chosen by comparing the cross-validation (CV) area under the curves (AUC) and their relative standard deviations (RSD). Clinical and radiological features were collected and analyzed; meaningful features were combined with radiomic features to establish the clinical-radiological-radiomic (CRR) models. The receiver operating characteristic (ROC) analysis was used to evaluate those models in validation set. Radiomic models and CRR models were compared by Delong test. RESULTS: 1218 and 1781 radiomic features were extracted from 2D ROI and 3D ROI of each sequence. The selected grade, Ki-67 index and their combination radiomic models were T1CE-2D-LASSO-LR, T1CE-3D-LASSO-NB, and T1CE-2D-LASSO-LR, with cross-validated AUCs on the training set were 0.857, 0.798, and 0.888, the RSDs were 0.06, 0.09, and 0.05, the validation set AUCs were 0.829, 0.752, and 0.904, respectively. Heterogeneous enhancement was found to be associated with high grade and Ki-67 status, while surrounding invasion was associated with the high grade status, peritumoral edema and cerebrospinal fluid space surrounding tumor were correlated with the high Ki-67 status. The Delong test showed that these significant radiological features did not significantly improve the predictive performance. The AUCs for CRR models predicting grade, Ki-67 index, and their combination in the validation set were 0.821, 0.753, and 0.906, respectively. CONCLUSIONS: This study demonstrated that MRI-based machine learning models could effectively predict the grade, Ki-67 index of meningioma. Models considering these two indices might be valuable for improving the predictive sensitivity and comprehensiveness of prediction of malignant biological behavior of meningioma.

Functional virus-specific memory T cells survey glioblastoma.

Glioblastoma multiforme (GBM) is among the most aggressive, treatment-resistant cancers, and despite standard of care surgery, radiation and chemotherapy, is invariably fatal. GBM is marked by local and systemic immunosuppression, contributing to resistance to existing immunotherapies that have had success in other tumor types. Memory T cells specific for previous infections reside in tissues throughout the host and are capable of rapid and potent immune activation. Here, we show that virus-specific memory CD8 + T cells expressing tissue-resident markers populate the mouse and human glioblastoma microenvironment. Reactivating virus-specific memory T cells through intratumoral delivery of adjuvant-free virus-derived peptide triggered local immune activation. This delivery translated to antineoplastic effects, which improved survival in a murine glioblastoma model. Our results indicate that virus-specific memory T cells are a significant part of the glioblastoma immune microenvironment and may be leveraged to promote anti-tumoral immunity.

Effectiveness of a multicomponent exercise program to reverse pre-frailty in community-dwelling Chinese older adults: a randomised controlled trial.

BACKGROUND: the Xiangya Hospital circuit training (X-CircuiT), was developed to reverse pre-frailty in Chinese older adults and determine potential mechanisms through which pre-frailty is reversed. METHODS: this randomised controlled trial was performed at Xiangya Hospital, Changsha, China from September 2020 to May 2021. Forty-eight pre-frail older adults were enrolled. Participants were randomly assigned (1:1) to X-CircuiT (46 min/session, three supervised sessions/week for 3 months at a community health centre) or control (1-time advice on physical activity without supervised exercise). The primary outcome was the proportion of participants with pre-frailty after 3-month intervention. The secondary outcomes included absolute risk reduction (ARR), number needed to treat (NNT), and the changes in senior fitness, body composition and clinical measures. RESULTS: among 48 participants (mean age, 72 years; women [65%]), 22 participants in the X-CircuiT (92%) and 21 participants in the control (88%) completed the study. After 3 months, the proportion of pre-frailty was significantly lower in the X-CircuiT group than the control (14% versus 95%, P < 0.001). The ARR and NNT were 82% [95% CI, 65-99] and 1 [1-2], respectively. X-CircuiT was associated with significant improvements in senior fitness indicators and body composition. No significant difference in blood chemistry, carotid ultrasound and echocardiography parameters was found between groups. No significant interaction was detected between sex, BMI, baseline peak oxygen consumption and study groups. CONCLUSION: this study demonstrates that X-CircuiT could significantly reverse pre-frailty in Chinese older adults. The underlying mechanisms may involve X-CircuiT-induced improvements in body composition and senior fitness.The trial is registered at Chictr.org.cn. Number: ChiCTR2100048125.

Parecoxib inhibits esophageal squamous cell carcinoma progression via the PDK1-AKT pathway.

BACKGROUND: Parecoxib plays an important role in inhibition of human cancer. However, the effect of parecoxib on esophageal squamous cell carcinoma (ESCC) is still not well known. The purpose of this study was to investigate the effect of parecoxib on ESCC and its underlying mechanism. METHODS: RNA-sequence analysis was performed to identify functional alterations and mechanisms. Cell cycle, proliferation, invasion, and migration were assessed using flow cytometry, CCK-8 assay, colony formation, transwell, and wound healing assays. Extracellular matrix (ECM) degradation was detected by substrate gel zymography and 3D cell culture assay. Western blotting was used to detect parecoxib-dependent mechanisms involving cell cycle, proliferation, invasion, and migration. Tumor formation in vivo was detected by mouse assay. RESULTS: Functional experiments indicated that parecoxib induced ESCC cell cycle arrest in G2 phase, and inhibited cell proliferation, invasion, and migration in vitro. Western blotting revealed that parecoxib downregulated the phosphorylation levels of AKT and PDK1, as well as the expression of the mutant p53, cyclin B1, and CDK1, while upregulating p21waf1. Parecoxib inhibited matrix metalloproteinase-2 (MMP2) secretion and invadopodia formation, which were related to ECM degradation. Furthermore, we found that parecoxib suppressed ESCC growth in heterotopic tumor models. CONCLUSION: Parecoxib inhibits ESCC progression, including cell cycle, proliferation, invasion, and migration, via the PDK1-AKT signaling pathway.

Ultranarrow spectral line of the radiation in double qubit-cavity ultrastrong coupling system.

The ultrastrongly coupling (USC) system has very important research significance in quantum simulation and quantum computing. In this paper, the ultranarrow spectrum of a circuit QED system with two qubits ultrastrongly coupled to a single-mode cavity is studied. In the regime of USC, the JC model breaks down and the counter-rotating terms in the quantum Rabi Hamiltonian leads to the level anti-crossing in the energy spectrum. Choosing a single-photon driving field at the point of avoided-level crossing, we can get an equivalent four-level dressed state model, in which the dissipation of the two intermediate states is only related to the qubits decay. Due to the electron shelving of these two metastable states, a narrow peak appears in the cavity emission spectrum. Furthermore, we find that the physical origin for the spectral narrowing is the vacuum-induced quantum interference between two transition pathways. And this interference effect couples the slowly decaying incoherent components of the density matrix into the equations of the sidebands. This result provides a possibility for the study of quantum interference effect in the USC system.

Vitamin D supplementation for the treatment of migraine: A meta-analysis of randomized controlled studies.

INTRODUCTION: It is not well established to use vitamin D supplementation for migraine, and this meta-analysis aims to explore the efficacy of vitamin D for migraine patients. METHODS: PubMed, EMbase, Web of science, EBSCO and Cochrane library databases were systematically searched up to May 2021, and we included randomized controlled trials (RCTs) exploring the effect of vitamin D for migraine patients. RESULTS: Six RCTs and 301 patients were included in the meta-analysis. Compared with control group in migraine patients, vitamin D supplementation could remarkably decrease headache attacks per month (MD = -2.74; 95% CI = -3.82 to -1.67; P < 0.00001), headache days per month (MD = -1.56; 95% CI = -2.44 to -0.68; P = 0.0005) and MIDAS score (MD = -5.72; 95% CI = -10.90 to -0.54; P = 0.03), but demonstrated no obvious influence on attack duration (MD = -2.20; 95% CI = -7.38 to 2.97; P = 0.40) or headache severity (MD = -0.56; 95% CI = -1.18 to 0.06; P = 0.08). CONCLUSIONS: Vitamin D supplementation provided additional benefits to treat migraine.

Establishment of a PEG-mediated protoplast transformation system based on DNA and CRISPR/Cas9 ribonucleoprotein complexes for banana.

BACKGROUND: To date, CRISPR/Cas9 RNP editing tools have not been applied to the genetic modification of banana. Here, the establishment of a PEG-mediated banana protoplast transformation system makes it possible to build an efficient DNA-free method for a site-directed mutagenesis system. RESULTS: Protoplasts constitute a versatile platform for transient expression in plant science. In this study, we established a PEG-mediated banana protoplast transformation system. This system was further optimized for successfully delivering CRISPR/Cas9 and CRISPR/Cas12a plasmids and CRISPR/Cas9 ribonucleoproteins (RNPs) for targeted delivery of the PDS gene into banana protoplasts. Specific bands were observed in PCR-Restriction Enzyme Digestion (PCR-RE) assays, and Sanger sequencing of single clones further confirmed the occurrence of indels at target sites. Deep amplicon sequencing results showed that the editing efficiency of the CRISPR/Cas9 system was higher than that of the other two systems. CONCLUSIONS: The PEG-mediated banana protoplast transformation system can serve as a rapid and effective tool for transient expression assays and sgRNA validation in banana. The application of the CRISPR/Cas9 RNP system enables the generation of banana plants engineered by DNA-free gene editing.

Rational design of a novel turn-on fluorescent probe for the detection and bioimaging of hydrazine with barbituric acid as a recognition group.

A novel turn-on fluorescent probe with barbituric acid as a unique recognition group has been rationally designed and synthesized using a facile method for detecting hydrazine. The 5-((7-(dimethylamino)-4,5-dihydronaphtho [1,2-b] thiophen-2-yl)methylene)pyrimidine-2,4,6 (1H,3H,5H)-trione (DPT) probe displays a large emission signal ratio variation (more than a 40-fold enhancement) in the presence of hydrazine under neutral conditions. Interestingly, a novel recognition mechanism based on a hydrazine-triggered addition-cyclisation-retro aldol was proposed and confirmed. Additionally, the DPT probe exhibits a low detection limit (5 × 10-8 M), applicable to the physiological pH range (3-12), a broad linear response range for hydrazine concentrations between 0 and 34 µM and a large Stokes shift (147 nm) for hydrazine detection in aqueous solution. Moreover, the DPT probe was successfully implemented for hydrazine imaging in vivo.

Comparison of Multiple Quantitative Evaluation Indices of Theoretical Knowledge and Clinical Practice Skills and Training of Medical Interns in Cardiovascular Imaging Using Blended Teaching and the Case Resource Network Platform (CRNP).

BACKGROUND This study aimed to compare multiple quantitative evaluation indices of levels of theoretical knowledge and clinical practice skills in training medical interns in cardiovascular imaging based on the use of the blended teaching (BT) online artificial intelligence (AI) case resource network platform (CRNP), including time and frequency indices and effectiveness of the CRNP. MATERIAL AND METHODS The study included 110 medical interns who were divided into the routine teaching (RT) group (n=55) and the blended teaching (BT) group (n=55). The two were assessed using the mini-clinical evaluation exercise (mini-CEX) that assessed clinical skills, attitudes, and behaviors and using an objective written questionnaire. The following four indices were compared between the RT and BT groups: the X-ray score (XS), the computed tomography angiography (CTA) score (CS), the cardiac magnetic resonance imaging (CMRI) score (MS), and the average score (AS). Seven assessment indicators included: the imaging description (ID), the qualitative diagnosis (QD), the differential diagnosis (DD), examination preparation (EP), interview skill (IS), position display (PD), and human care (HC). Indicators of CRNP use included: number of times (TN), average duration (AD), single maximum duration (SMD), and total duration (TD). RESULTS AS significantly correlated with AD (rAD=0.761) and TD (rTD=0.754), and showed moderate correlation with TN (rTN=0.595), but weak correlation with SMD (rSMD=0.404). CONCLUSIONS Levels of theoretical knowledge and clinical practice skills during medical intern training in cardiovascular imaging based on BT using the CRNP teaching technology improved theoretical knowledge and practical skills.

Deletion of sorting nexin 27 suppresses proliferation in highly aggressive breast cancer MDA-MB-231 cells in vitro and in vivo.

BACKGROUND: Sorting Nexin 27 (SNX27) belongs to a family of sortin nexins and possesses a unique binding domain at the C-terminus which mediates protein-protein interaction in intracellular trafficking, membrane remodeling, organelle motility, and tight junctions. However, its role in cancer development, especially in vivo, remains largely unknown. METHODS: We have generated a stable SNX27 knockdown clone in a highly aggressive breast cancer cell line MDA-MB-231 using an inducible lentiviral shRNA system. Cell migration and proliferation of SNX27 knockdown (KD) cells were compared with wild-type (WT) cells by MTT and wound healing assay, respectively. The differences in colony formation between SNX27-KD and WT cells were detected by soft agar culture and matrigel 3D culture. Furthermore, tumor growth was examined in a xenograft nude mouse model using SNX27-KD and WT MDA-MB-231 cells. The critical EMT (epithelial-mesenchymal transition) regulators were examined in vitro and in vivo. RESULTS: The wound healing assay showed that SNX27 knockdown significantly decreased cell motility and proliferation. Colony formation in soft agar showed that the SNX27 knockdown cells formed significantly fewer and smaller colonies than the parental MDA-MB-231 cells. Western blots and immunostaining showed that knockdown of SNX27 led to increased expression of E-cadherin and ß-catenin proteins, which facilitate adhesion formation and reverse EMT. EMT is a cellular program that allows polarized, immotile epithelial cells to convert to motile mesenchymal cells, promoting carcinoma invasion. The expression levels of Vimentin, the transcription factor of EMT, and tight junction protein Claudin-5, were significantly diminished in the SNX27 knockdown cells. The expression of PCNA, the cell proliferation marker, was increased in SNX27-KD cells transfected with E-cadherin siRNA. In a xenograft nude mouse model, we found that knockdown of SNX27 significantly inhibited tumor growth. The tumors from mice with SNX27-KD cells showed less proliferation compared to tumors from mice injected with wildtype cells. The increase in E-cadherin and ß-catenin and decrease in Vimentin and Claudin-5 were observed in tumors of mice injected with SNX27-KD cells. CONCLUSIONS: Our data have demonstrated that SNX27 plays a crucial role in tumor growth in vitro and in vivo.

Excavating precursors from the traditional Chinese herb Polygala tenuifolia and Gastrodia elata: Synthesis, anticonvulsant activity evaluation of 3,4,5-trimethoxycinnamic acid (TMCA) ester derivatives.

Epilepsy is a group of neurological disorders characterized by recurrent seizures that disturbs about 60 million people worldwide. In this article, a novel series of 3,4,5-trimethoxycinnamic acid (TMCA) ester derivatives 1-35 were designed inspired from the traditional Chinese herb pair drugs Polygala tenuifolia and Gastrodia elata and synthesized followed by in vivo and in silico evaluation of their anticonvulsant potential. All the synthesized derivatives were biologically evaluated for their anticonvulsant potential using two acute model of seizures induced in mice, the maximal electroshock (MES) and sc-pentylenetetrazole (PTZ) models. Simultaneously, the motor impairment as a surrogate of acute neurotoxicity and in vitro screening of cytotoxicity against HepG-2 cells line were assessed through the rotarod performance test and CCK-8 assay, respectively. In addition, the physicochemical and pharmacokinetic parameters of the active compounds were determined. Our results showed that compounds 5, 7, 8, 13, 20, 25, 28, 30 and 32 exhibited preferable anticonvulsant activity in primary evaluation, with compounds 28 and 32 being the most promising anticonvulsant agents in according to results of subsequent pharmacology and toxicity evaluation. Additionally, the molecular modeling experiments predicted good binding interactions of part of the obtained active molecules with the gamma-aminobutyric acid (GABA) transferas. Therefore, it could be concluded that the synthesized derivatives 28 and 32 would represent useful lead compounds for further investigation in the development of anticonvulsant agents.

Synthesis and anti-tyrosinase mechanism of the substituted vanillyl cinnamate analogues.

This study aimed to synthesize and screen tyrosinase inhibitors for delay fruit browning. A series of vanillyl cinnamate analogues were designed and synthesized by simple processes, and the inhibitory effects of all the synthesized derivatives on mushroom tyrosinase were evaluated. In the enzymatic activity test, compounds 21, 22, and 26 had significant (P < 0.05) effect on mushroom tyrosinase at a preliminary screening dose (1 mg/mL in vitro). IC50 analysis showed that the IC50 values of compounds 21, 22 and 26 were 268.5 µM, 213.2 µM and 413.5 µM, respectively. In the cytotoxicity evaluation, Cell Counting Kit-8 (CCK-8) assay showed that compounds 21, 22 and 26 had no significant effect on the proliferation of hepatocyte L02 and B16 melanoma cells at the dosage of 25-200 µM. Inhibition of tyrosinase activity and melanin content in B16 melanoma cells investigations indicated that compounds 21, 22 and 26 inhibited both cellular tyrosinase activity and melanin content dose-dependently and more strongly than the reference standard arbutin. The UV-visible spectra showed compound 22 inhibits the formation of dopamine quinone, further the molecular docking analysis of compound 22 with tyrosinase (PDB: 2Y9X) indicated that compound 22 interacted with the amino acid residues of tyrosinase. The results of anti-browning test showed that compounds 21, 22 and 26 had significant tyrosinase inhibition and anti-browning effects on fresh-cut apple slices at 4 °C in 48 h. Compound 22 could be used as novel tyrosinase inhibitor to delay fruit browning.

Exogenous succinic acid mediates responses of Larix olgensis A. Henry to cadmium stress.

Trace metal contamination of soil is an increasing problem. Organic acid application can restore trace metal elements such as cadmium (Cd) in contaminated soil. Changbai larch (Larix olgensis A. Henry) is an economically important forestry species in northeast China; however, growth is inhibited by severe Cd contamination. We investigated the effects of different concentrations of exogenous succinic acid (SA) on Cd tolerance and physiological and morphological toxicity in L. olgensis seedlings. Seedlings were planted in pots containing Cd-contaminated or uncontaminated Haplic Cambisol. Seedlings in Cd-contaminated soil were treated daily with SA solution at 0, 0.04, 0.2, 1.0, and 2.0 mmol kg-1 of soil for 10, 20 or 30 days. Cd treatment induced seedling damage and significantly increased the relative conductivity and malondialdehyde content of the leaves, inhibiting soluble protein and proline contents, superoxide dismutase and peroxidase activity, chlorophyl fluorescence and pigment content. Decreases in the length, surface area, volume of roots and leaves, and specific root length were also observed. Effects increased in control plants with time. SA treatment also reduced the Cd content of the fine roots and leaves and Mg, K, and Ca contents. Moreover, plant growth was significantly promoted and damage was reversed, especially at 5.0 and 10.0 mmol L-1 SA for 30 days. SA therefore alleviated Cd-induced injury, improving tolerance to Cd stress. SA application combined with afforestation could therefore help restore Cd-contaminated soil in northeast China. Further studies aimed at determining the detoxification mechanism of L. olgensis seedlings are now required.

Morphology of the Male Reproductive System and Spermiogenesis of Dendroctonus armandi Tsai and Li (Coleoptera: Curculionidae: Scolytinae).

Studying the reproductive attributes of pests is central to understanding their life cycle history and in crafting management strategies to regulate, if not bring down, their population below threshold levels. In this article, the morphology of the male reproductive tract, topology of the spermatozoa, and salient features of spermiogenesis in the Chinese white pine beetle, Dendroctonus armandi Tsai and Li was studied to provide baseline information for further pest management studies. Results showed that male reproductive tract of this species differs from those documented in other Coleopterans by having 20 testicular tubules in each testis and the presence of two types of accessory glands. The spermatozoon is seen having peculiar characteristics such as an "h"-shaped acrosomal vesicle with a "puff"-like expansion, one centriole, one large spongy body, and two accessory bodies. Despite with some morphological differences of the male reproductive organ, spermatogenesis in this organism is similar to other Coleopterans. Overall, detailed studies regarding the components of the primary male reproductive organ of this beetle species would expand the knowledge on the less-understood biology of Coleopteran pests and would help in designing regulatory measures to conserve endemic and indigenous pine trees in China.