[Effect of consolidation before allogeneic hematopoietic stem cell transplantation for non-favorable acute myeloid leukemia patients with first complete remisson and negative minimal residual disease]

目的

探讨异基因造血干细胞移植（allo-HSCT）前巩固化疗对第1次形态学完全缓解且微小残留病阴性（CR₁/MRD⁻）中/高危急性髓系白血病（AML）患者预后的影响。

方法

对2010年1月至2019年3月在CR₁/MRD⁻状态下接受allo-HSCT的155例中/高危AML（不含急性早幼粒细胞白血病）患者进行回顾性分析。

结果

全部155例患者中，102例获得CR₁/MRD⁻后接受移植前巩固化疗（巩固组），53例获得CR₁/MRD⁻后直接行allo-HSCT（非巩固组），两组中位年龄分别为39（18~56）岁、38（19~67）岁。巩固组、非巩固组移植后5年总生存率分别为（59.3±7.5）%、（62.2±6.9）%（P=0.919），无复发生存率分别为（53.0±8.9）%、（61.6±7.0）%（P=0.936），累积复发率分别为（21.9±5.4）%、（18.3±6.0）%（P=0.942），非复发死亡率分别为（22.4±4.3）%、（28.4±6.5）%（P=0.464）。多因素分析显示，移植前是否接受巩固化疗及其疗程（<2个/≥2个）对预后无显著影响。

结论

中/高危AML患者可在获得CR₁/MRD⁻后直接进行allo-HSCT。

[Prognostic value of donor chimerism at +90 days after allogeneic hematopoietic stem cell transplantation in young patients with intermediate-risk acute myeloid leukemia]

Objective: To investigate the relationship between donor chimerism and relapse after allogeneic hematopoietic stem cell transplantation (allo-HSCT) . Methods: The clinical data of 105 patients with acute myeloid leukemia (AML) who underwent allo-HSCT and recurrence-free survival>90 days from January 2010 to January 2019 were retrospectively analyzed. The bone marrow samples were collected at 15, 30, 60, 90, 180, 270, 360 days after transplantation. Donor chimerism was detected by single nucleotide polymorphism (SNP) -PCR. Results: Of the 105 patients, 43 cases were male and 62 cases were female, with a median age of 38 (16-60) years. Till April 2019, the median follow-up was 843 (94-3 261) days. Ninety days after transplantation, 18 cases relapsed, 33 cases died, and 72 cases survived. The 3-year overall survival (OS) rate was (66.8±5.1) %, and the recurrence-free survival (RFS) rate was (65.1±5.0) %. Pre-transplant disease status, pre-transplant minimal residual disease (MRD) , and 90 day post-transplantation chimerism were independent risk factors related to RFS. The risk of recurrence was significantly increased in patients with a donor chimerism rate ≤97.24% at 90 days after transplantation[HR=6.921 (95%CI 2.669-17.950) , P<0.001], which was considered as a sign of early relapse. Conclusion: SNP-PCR is an applicable method for detecting donor chimerism in patients after allo-HSCT. Chimerism rate equal or less than 97.24% at 90 days after transplantation predicts a higher risk of relapse.

[Clinical and prognostic values of TP53 mutation in patients with acute myeloid leukemia]

Objective: To explore the clinical and prognostic values of TP53 gene mutation in patients with acute myeloid leukemia (AML) . Methods: A retrospective analysis of 265 newly diagnosed AML patients with next-generation sequencing (NGS) data in the Hematology Department of Changhai Hospital from January 2010 to January 2019 was performed. Mutation analysis was carried out by targeted sequencing technology including 200 hematological malignancy related genes. The association of TP53 mutation with clinical features was analyzed. Results: Alterations in TP53 were found in 20 (7.5%) patients, including 17 case (6.4%) of missense mutations, 2 cases (0.7%) of frame-shift deletion mutations and 1 case (0.4%) of splicing sites mutation. A total of 23 kinds of TP53 mutations were detected, most of them (16, 69.6%) were located in the DNA binding domain of exon 5-8, 4 in the DNA binding domain of exon 3-4, 2 in exon 10 and 1 in splice site, respectively. The median age of patients with TP53 alterations was higher than those without [52 (26-72) years old vs 45 (14-75) years old, P= 0.008]. The frequency of complex karyotypes was higher in patients with TP53 alterations than those without [45.0% (9/20) vs 6.1% (15/245) , P<0.001]. Median overall survival (OS) of patients with TP53 alterations was shorter than those without[14.1 (95%CI 6.78-21.42) months vs 31.4 (95%CI 13.20-49.59) months, P=0.029]. The OS of patients treated with "Decitabine + CAG" was superior than that of patients treated with "3 + 7" regimen [30.0 (95%CI 27.35-38.84) months vs 12.5 (95%CI 5.80-19.19) months, P=0.018]. Multivariate analysis indicated that TP53, DNMT3A and USH2A alterations, WBC ≥ 12.45×10(9)/L had negative impacts on OS. Conclusion: The frequency of TP53 mutation was 7.5% in our cohort. Most mutations were located in the DNA binding domain. TP53 alterations were strongly associated with older age, complex karyotype and shorter OS. Decitabine-based induction chemotherapy and hematopoietic stem cell transplantation may improve OS, more cases and/or multicenter randomized studies are needed for further confirmation.

miR‑218 functions as a tumor suppressor gene in cervical cancer

Previous microRNA (miR) microarray analysis revealed that miR‑218 is downregulated in cervical cancer tissues. The present study aimed to further evaluate the expression of miR‑218 in cervical cancer specimens, determine the association between its expression with disease progression, and investigate the roles of miR‑218 in cervical cancer cells. Tissue specimens were obtained from 80 patients with cervical squamous cell carcinoma, 30 patients with high‑grade cervical intraepithelial neoplasia [(CIN) II/III] and 15 patients with low‑grade CIN (CINI); in addition, 60 plasma samples were obtained from patients with cervical cancer, and 15 normal cervical tissue specimens and 30 plasma samples were obtained from healthy women. These samples were used for analysis of miR‑218 expression via reverse transcription‑-quantitative PCR. In addition, tumor cells were transfected with miR‑218 mimics, human papillomavirus (HPV)16 E6/E7 small interfering RNA, or their respective negative controls to determine the viability, colony formation, migration and invasion of cells using MTT, colony formation, wound healing and Transwell assays, respectively. Target genes of miR‑218 were bioinformatically predicted and analyzed using Gene Ontology (GO) terms. The results revealed that miR‑218 was downregulated in the tumor tissues and plasma of patients with cervical cancer, with expression associated with the advanced clinicopathological characteristics of patients, including HPV positivity, tumor size, blood vessel invasion and lymph node metastasis. Furthermore, miR‑218 overexpression reduced tumor cell viability and xenograft growth, and suppressed tumor cell migration and invasion. HPV was detected in 75% of the 80 patients with cervical cancer, and HPV positivity was inversely associated with miR‑218 expression. In addition, bioinformatics analysis predicted that roundabout guidance receptor 1 (ROBO1) was a target gene of miR‑218; miR‑218 overexpression significantly reduced ROBO1 levels. Furthermore, GO analysis revealed that ROBO1 was involved in regulating cell proliferation, adhesion and migration, and the cell cycle. In conclusion, the findings of the present study suggested that miR‑218 may possess antitumor activities in cervical cancer.

Pulmonary Infection Within 100 Days After Transplantation Impaired Platelet Recovery in Patients with Hematologic Malignancies: A Propensity-Score-Matched Analysis

Background

Pulmonary infection is one of the life-threatening complications occurring during allogeneic hematopoietic stem cell transplantation (alloHSCT), even when prophylactic measures have been employed. Few studies have investigated whether pulmonary infection affects platelet recovery during alloHSCT.

Material/Methods

We retrospectively reviewed 253 consecutive patients with hematologic diseases who received alloHSCT in our institute. Among them, 62 patients (25%) had pulmonary infection within 100 days after alloHSCT. Using the one-to-two propensity-score matching logistic model, 50 patients with pulmonary infection and 100 patients without were included based on age, disease and stage, time from diagnosis to transplantation, infused CD34⁺ cells, and mononuclear cells.

Results

The incidences of prolonged thrombocytopenia in patients with pulmonary infection were 44% (22/50) and 9% (9/100) in the corresponding matched group (P<0.001). The mean time for platelet engraftment in patients with and without pulmonary infection were 19.29±13.96 days and 13.94±4.12 days (P=0.012), respectively. Multivariable logistic regression showed that pulmonary infection was an independent risk factor for impaired platelet recovery (OR: 5.335, 95% CI: 2.735–10.407, P<0.001). Impaired platelet recovery was associated with shorter survival and higher treatment-related mortality.

Conclusions

Our results indicate that patients with pulmonary infection within 100 days after alloHSCT are more likely to suffer from impaired platelet recovery and have inferior long-term survival.

[Rosai-Dorfman disease: a clinicopathologic analysis and whole exome sequencing in 23 cases]

目的

分析Rosai-Dorfman disease（RDD）的临床病理特征，利用全基因组外显子测序探讨RDD的发病机制。

方法

回顾性分析第二军医大学附属长海医院、长征医院2010年1月至2018年7月收治的23例RDD患者临床病理资料，并对9例患者石蜡包埋组织标本进行了全基因组外显子测序。

结果

23例RDD患者中位年龄47（10~79）岁，19例为结外型，3例为淋巴结型，1例为混合型。所有患者均接受了手术切除病灶，19例患者中位随访24（1~67）个月，均无复发。病理形态主要表现为淋巴结窦内或结外组织中组织细胞增生伴有噬淋巴细胞现象，免疫组化示组织细胞表达S100、CD68、CD163，不表达CD1a。全基因组外显子测序发现mTOR、KMT2D和NOTCH1基因突变。

结论

mTOR、KMT2D和NOTCH1基因突变可能参与了RDD的发病机制，其临床意义仍需要进一步研究。

[Efficacy of Hyper-CVAD/MA and CHALL-01 regimens in the treatment of Philadelphia chromosome-positive adult acute lymphoblastic leukemia patients under 60 years old]

Objective: To compare the difference of efficacy between traditional Hyper-CVAD/MA regimen and the adolescents inspired chemotherapy regimen, CH ALL-01, in treatment of adult Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph(+) ALL) . Methods: In this study we retrospectively analyzed 158 Ph(+) ALL patients receiving Hyper-CVAD/MA regimen (n=63) or CHALL-01 regimen (n=95) in our center and Changzheng hospital from January 2007 to December 2017, excluding patients with chronic myeloid leukemia in blast crisis. Tyrosine kinase inhibitor (TKI) was administered during induction and consolidation chemotherapy. Patients who underwent hematopoietic stem cell transplantation received TKI as maintenance therapy. Results: Of them, 91.1% (144/158) patients achieved complete remission (CR) after 1-2 courses of induction. CR rate was 90.5% (57/63) for patients in Hyper-CVAD/MA group and 91.6% (87/95) for patients in CHALL-01 group. There was no difference in CR rates between the two groups (χ(2)=0.057, P=0.811) . The last follow-up was June 2018. A cohort of 134 CR patients could be used for further analysis, among them, 53 patients received Hyper-CVAD/MA regimen and other 81 patients received CHALL-01 regimen. The molecular remission rates were significantly higher in CHALL-01 group (complete molecular response: 44.4%vs 22.6%; major molecular response: 9.9% vs 18.9%) (χ(2)=7.216, P=0.027) . For the patients in Hyper-CVAD/MA group, the 4-year overall survival (OS) was 44.81% (95%CI: 30.80%-57.86%) and the 4-year disease free survival (DFS) was 37.95% (95%CI: 24.87%-50.93%) . For patients received CHALL-01 regimen, the 4-year OS was 55.63% (95%CI: 39.07%-69.36%) (P=0.037) and 4 year DFS was 49.06% (95%CI: 34.24%-62.29%) (P=0.015) , while there was no significant difference in 4 year cumulative incidence of relapse (CIR) (P=0.328) or cumulative incidence of nonrelapse mortality (CI-NRM) (P=0.138) . The rate of pulmonary infection was lower in patients received CHALL-01 regimen compared with patients received Hyper-CVAD regimen (43.4% vs 67.9%, χ(2)=7.908, P=0.005) . Conclusions: Outcome with CHALL-01 regimen appeared better than that with the Hyper-CVAD/MA regimen in Ph(+) ALL, which has lower incidence of pulmonary infection, higher molecular remission rate and better OS and DFS.

Aplastic Anemia Preconditioned with Fludarabine, Cyclophosphamide, and Anti-Thymocyte Globulin

Background

Graft rejection and graft versus host disease (GvHD) have impeded the success of hematopoietic cell transplantation for severe aplastic anemia (SAA) patients. There is no sufficient data to identify the outcomes of peripheral blood stem cell transplantation (PBSCT) in SAA patients, especially for adult SAA patients. The aim of this study was to evaluate the outcomes of adult SAA patients undergoing PBSCT with the FCA regimen. The FCA regimen includes fludarabine, cyclophosphamide, and anti-thymocyte globulin (ATG).

Material/Methods

We report our experience with 46 adult SAA patients who underwent PBSCT with the FCA regimen. Thirty SAA patients who received only cyclophosphamide and ATG (CA) regimen were used as controls. Complications and survival outcomes were evaluated and compared.

Results

There was a significantly higher percentage of patients who achieved >95% donor chimerism by day 30 in the FCA group. The 5-year event-free survival (EFS) rate in the FCA group was higher than that in the CA group (95.4% versus 73.3%). In addition, the 5-year rejection rate (RR) in the FCA group was lower than that in the CA group (4.6% versus 23.6%). A multivariable model identified the FCA regimen as an independent factor affecting EFS and RR. However, GvHD and serious infection did not differ between the 2 groups. For patients with an unrelated donor, the FCA regimen had a higher EFS and a lower RR than the CA regimen.

Conclusions

The FCA regimen for PBSCT in adult SAA patients compared favorably to the CA regimen. It can improve EFS and reduce graft rejection, especially for unrelated donor PBSCT.

[Retrospective analysis of 4 rare cases of temporomandibular joint disc ossification]

Objective: To summarize the clinical manifestation and treatment of temporomandibular joint (TMJ) disc ossification, providing reference for clinical diagnosis and treatment of TMJ disc ossification. Methods: From January 2006 to January 2018, 4 patients with TMJ disc ossification (2 males and 2 females, aged 20-55 years with an average age of 35.5 years) which were admitted to the Department of Oral and Maxillofacial Surgery, Shenzhen Second People's Hospital were analyzed retrospectively. Ossification of TMJ disc was found in 4 cases during TMJ surgery. Two cases underwent partial ossification resection plus disc reduction and anchorage, and two cases underwent discectomy plus temporalis myofascial flap replacement. The causes, clinical manifestations and surgical effects of TMJ disc ossification were analyzed by comparing the maximal interincisal opening, visual analogue scale (VAS) score and MRI imaging indexes before and after operation. Results: The history of anterior disc displacement of TMJ in 4 patients was long (average 11.5 years). In clinic, TMJ disc ossification was characterized by TMJ pain and limitation of mouth opening. The maximal interincisal opening was (32.1±6.1) mm and the VAS score was (7.3±0.4) before operation. MRI showed that the displaced discs of the affected sides were displaced and the condyle bones were worn. During the operation, ossification of TMJ discs was found yellow and hard, and the original elasticity was lost. Pathologic findings showed that the TMJ disc cartilage were ossified to osteoid tissue. Under the microscope, bone cells scattered around the bone cells and red trabecular bone were seen, and there were bone trabecula formed. In a follow-up of one year, TMJ pain was significantly decreased [VAS: (1.7±0.2)], and the maximal interincisal opening was (38.5±2.2) mm. MRI showed that the TMJ disc returned to normal position, and the sign of repairing and reconstruction of condyle bone could be found. Conclusions: Long term displacement of TMJ disc may cause ossification with pain and limitation of interincisal opening. According to the degree and extent of ossification, partial ossification plus disc reduction and anchorage or discectomy plus temporalis myofascial flap replacement is feasible, and the clinical effects are satisfactory.

A distinct glycerophospholipid metabolism signature of acute graft versus host disease with predictive value

BACKGROUND

Acute graft-versus-host disease (aGvHD) is a major factor that limits the successful outcomes of allogeneic hematopoietic cell transplantation (alloHSCT). Currently there are few validated biomarkers that can help predict the risk of aGvHD in clinical settings.

METHODS

We performed an integrated metabolomics and transcriptomics study and identified biomarkers that distinguish alloHSCT recipients with aGvHD from alloHSCT recipients without aGvHD in two separate cohorts.

RESULTS

Pathway analysis of 38 significantly altered metabolites and 1148 differentially expressed genes uncovered a distinctly altered glycerophospholipid (GPL) metabolism network. Subsequently, we developed an aGvHD risk score (GRS) based on 5 metabolites markers from GPL metabolism to predict the risk of aGvHD. GRS showed a positive predictive value of 92.2% and 89.6% in the training and validation cohorts, respectively. In addition, high GRS was correlated with poor overall survival. Gene expressions of GPL-related lipases were significantly altered in aGvHD samples, leading to dysregulated GPLs.

CONCLUSIONS

Using integrative "Omic" analysis, we unraveled a comprehensive view of the molecular perturbations underlying the pathogenesis of aGvHD. Our work represents an initial investigation of a unique metabolic and transcriptomic network that may help identify aGvHD at an early stage and facilitate preemptive therapy.

FUNDING

National Natural Science Foundation of China (NSFC; 81530047, 81870143, 81470321, 81770160, 81270567, 81270638, 81573396, 81703674). Shanghai Sailing Program from Science and Technology Commission Shanghai Municipality (17YF1424700). Scholarship from Shanghai Municipal Health and Family Planning Commission (2017BR012). Special Clinical Research in Health Industry in Shanghai (20184Y0054).

Bioinspired extracellular vesicles embedded with black phosphorus for molecular recognition-guided biomineralization

Extracellular vesicles (EVs) are involved in the regulation of cell physiological activity and the reconstruction of extracellular environment. Matrix vesicles (MVs) are a type of EVs released by bone-related functional cells, and they participate in the regulation of cell mineralization. Here, we report bioinspired MVs embedded with black phosphorus (BP) and functionalized with cell-specific aptamer (denoted as Apt-bioinspired MVs) for stimulating biomineralization. The aptamer can direct bioinspired MVs to targeted cells, and the increasing concentration of inorganic phosphate originating from BP can facilitate cell biomineralization. The photothermal effect of the Apt-bioinspired MVs can also promote the biomineralization process by stimulating the upregulated expression of heat shock proteins and alkaline phosphatase. In addition, the Apt-bioinspired MVs display outstanding bone regeneration performance. Our strategy provides a method for designing bionic tools to study the mechanisms of biological processes and advance the development of medical engineering.

Low Platelet Counts at Diagnosis Predict Better Survival for Patients with Intermediate-Risk Acute Myeloid Leukemia

BACKGROUND

Aggressive growth of primitive and immature cells in the bone marrow results in reductions in megakaryocyte and platelet (PLT) counts, leading to thrombocytopenia in acute myeloid leukemia (AML). However, not all AML patients show thrombocytopenia at the time of diagnosis, and the association of PLT count with patient survival is largely unknown.

METHODS

A retrospective study was performed to determine PLT counts at diagnosis in the peripheral blood in 291 newly diagnosed AML patients and assess the association of PLT counts with the overall survival (OS) and disease-free survival (DFS) of these patients.

RESULTS

Low PLT counts (≤40 × 109/L) were associated with better outcomes for the whole cohort (5-year OS, 55.1 ± 3.8 vs. 35.3 ± 3.5%, p < 0.001; 5-year DFS, 49.1 ± 3.8 vs. 25.7 ± 4.0%, p < 0.001) and intermediate-risk patients (5-year OS, 64.5 ± 5.4 vs. 41.0 ± 4.8%, p < 0.001; 5-year DFS, 60.8 ± 5.6 vs. 28.6 ± 5.6%, p < 0.001). Moreover, low PLT counts were related to deeper molecular remission. Low PLT counts correlated with better survival of intermediate-risk AML patients treated with chemotherapy only. Allogeneic hematopoietic stem cell transplantation attenuated the negative impact of high PLT counts on the survival of intermediate-risk patients. Furthermore, univariate and multivariate analyses demonstrated that PLT count at diagnosis was an independent prognostic factor for intermediate-risk AML.

CONCLUSION

PLT count at diagnosis predicts survival for patients with intermediate-risk AML.

Simplified LC-MS/MS method for quantification of IG-105, a novel tubulin ligand, and its application to the pharmacokinetic study in rats at the anticancer effective dose

IG-105, N-(2, 6-dimethoxypyridine-3-yl)-9-methylcarbazole-3-sulfonamide, a novel carbazole sulfonamide, shows a potent anticancer activity in a variety of human tumor cells in vitro and in vivo. In the present study, a rapid and convenient liquid chromatography/tandem mass spectrometry (LC-MS/MS) method was developed and applied to the pharmacokinetic study of IG-105 in rats. Chromatographic separation was accomplished on a C₁₈ column using an isocratic mobile phase of acetonitrile-water-acetic acid (56:44:0.2, v/v/v). The ion transitions of IG-105 and combretastatin A4 (internal standard) in selected reaction monitoring mode were m/z 398→154 and m/z 317→286, respectively. The assay exhibited good linearity over the range of 2-512 ng/mL. Intra- and inter-day precisions were within 8.2 %, and the accuracies ranged from -6.0 to 3.7 %. The extraction recoveries were higher than 90 %, and the matrix effects were negligible. All quality control samples were stable at different storage conditions. The validated LC-MS/MS method was successfully applied to a preclinical pharmacokinetic study of IG-105 in rats after a single oral dose of 100, 250, or 1000 mg/kg which showed tumor growth inhibition activity. The absorption of IG-105 was proved to be rapid but saturated to a certain extent into the blood circulation, from where it was distributed and eliminated gradually.

Knockdown of MAML1 inhibits proliferation and induces apoptosis of T-cell acute lymphoblastic leukemia cells through SP1-dependent inactivation of TRIM59

Notch exerts important functions in cell proliferation, survival, and differentiation, which plays a critical role in tumor development when aberrantly activated. Mastermind-like protein 1 (MAML1) has been functioning as crucial coactivators of Notch receptors and is required for stable formation of Notch transcriptional complexes. However, the mechanism whereby MAML1 induces T-cell acute lymphoblastic leukemia (T-ALL) tumorigenesis is largely unknown. The CCK-8 and flow cytometry assay were performed to examine the effect of MAML1 knockdown on T-ALL cell proliferation, apoptosis, and cell cycle. The expression of MAML1, cell cycle, and apoptosis-related gene, as well as TRIM family members and specific protein 1 (SP1) was measured by western blot analysis and qPCR. Our results showed that MAML1 knockdown significantly inhibited cell proliferation and induced G0/G1 cell cycle arrest and apoptosis in Jurkat and MOLT-4 cells. Cell cycle and apoptosis-related gene expression, including CDK2, Bcl-2, Bax, and Bad, was modified by the MAML1 knockdown. MAML1 knockdown obviously inhibited the CDK2 and Bcl-2 expression and increased the Bax, p53, and Bad expression. Moreover, the TRIM family members, including TRIM13, TRIM32, TRIM44, and TRIM59, were significantly decreased by the MAML1 knockdown, with the highest decrease detected in TRIM59 expression. Interesting, overexpression of SP1 not only increased the expression of MAML1 and TRIM59, but also promoted the promoter activation of TRIM59. Taken together, knockdown of MAML1 inhibits proliferation and induces apoptosis of T-ALL cells through SP1-dependent inactivation of TRIM59, and therefore suggest that MAML1-SP1-TRIM59 axis may serve as potentially interesting therapeutic targets for treatment of T-ALL.

Characterizing nitric oxide emissions from two typical alpine ecosystems

A portion of alpine meadows has been and will continue to be cultivated due to the concurrent increasing demands for animal- and crop-oriented foods and global warming. However, it remains unclear how these long-term changes in land use will affect nitric oxide (NO) emission. At a field site with a calcareous soil on the Qinghai-Tibetan Plateau, the authors measured the year-round NO fluxes and related variables in a typically winter-grazed natural alpine meadow (NAM) and its adjacent forage oat field (FOF). The results showed that long-term plow tillage, fertilization and growing forage oats significantly yielded ca. 2.7 times more (p < 0.01) NO emissions from the FOF than the NAM (conservatively 208 vs. 56 g N/(ha·year) on average). The spring freeze-thaw period and non-growing season accounted for 17%-35% of the annual emissions, respectively. The Q₁₀ of surface soil temperature (T_s) was 8.9 in the NAM (vs. 3.8 in the FOF), indicating increases of 24%-93% in NO emissions per 1-3 °C increase. However, the warming-induced increases could be smaller than those due to land use change and management practices. The T_s and concentrations of ammonium, nitrate and water-extractable organic carbon jointly explained 69% of the variance in daily NO fluxes from both fields during the annual period (p < 0.001). This result indicates that temporally and/or spatially distributed NO fluxes from landscapes with calcareous soils across native alpine meadows and/or fields cultivated with forage oats can be predicted by simultaneous observations of these four soil variables.

Dual-Aptamer-Conjugated Molecular Modulator for Detecting Bioactive Metal Ions and Inhibiting Metal-Mediated Protein Aggregation

Bioactive metal ions play important roles in both physiological and pathological processes. Developing biosensing probes for bioactive metal ion detection can contribute to fields including disease diagnosis and therapy and studying the mechanisms of biological activities. In this work, we designed a dual-aptamer-conjugated molecular modulator that can detect Zn²⁺ and further inhibit Zn²⁺-induced amyloid β (Aβ) aggregation. The molecular modulator is able to selectively target Aβ species and block Zn²⁺ due to the specific recognition capability of aptamers. With the binding of Zn²⁺, the fluorescence signal of this molecular modulator is restored, thus allowing for Zn²⁺ detection. More importantly, this molecular modulator can inhibit the generation of Zn²⁺-triggered Aβ aggregates due to the trapping of Zn²⁺ around Aβ species. Circular dichroism measurements reveal that the dual-aptamer-conjugated molecular modulator prevents the conformational transition of the Aβ monomer from a random coil to a β-sheet. Furthermore, after treating with the molecular modulator, no Aβ aggregate is observed in the Aβ solution with added Zn²⁺, demonstrating that Aβ aggregation is successfully inhibited by this molecular modulator. Our approach provides a promising tool for detecting bioactive metal ions and studying the molecular mechanisms behind life activities.

Effects of dibutyl phthalate and di(2-ethylhexyl) phthalate with their metabolites on CYP2C9*1 and CYP2C19*1 activities in vitro

The aim of this article is to assess the effect of phthalates on the activities of CYP2C9 and CYP2C19 in vitro. In this study, recombinant CYP2C9*1 and CYP2C19*1 microsomes were used to investigate the effects of phthalates and their metabolites on corresponding enzyme activities in vitro. 2-100 μM substrate of enzyme was incubated with series concentration of phthalates for 30 min at 37 °C. The metabolic products were detected using ultra-high performance liquid chromatography (UHPLC) and ultra-high performance liquid chromatography-mass spectrometry (UHPLC-MS/MS) methods. The results showed dibutyl phthalate (DBP) significantly inhibited CYP2C9*1 with an activity inhibition rate of 67.3% and half-maximal inhibitory concentration (IC50) of 29.63 μmol L^-1, but its metabolite monobutyl phthalate (MBP) had no significant effect. On the other hand, di(2-ethylhexyl)phthalate (DEHP) had no effect on CYP2C9*1, but its metabolite monoethylhexyl phthalate (MEHP) significantly inhibited the enzyme activity with an activity inhibition rate of 90.6% and IC50 of 6.37 μmol L^-1. With regards to CYP2C19*1, DBP completely inhibited the enzyme activity with an activity inhibition rate of 100% and IC50 of 2.63 μmol L^-1, but its metabolite MBP had no effect on it. DEHP and MEHP also inhibited the activity of CYP2C19*1. Further investigation showed MEHP was a competitive inhibitor of CYP2C9*1 (Ki = 7.063 μmol L^-1), and DBP was a competitive inhibitor of CYP2C19*1 (Ki = 7.013 μmol L^-1) against their substrates, both phthalates were non-competitive inhibitors of the cofactor NADPH. Our results suggested that DBP, DEHP, and their metabolites exhibited significant inhibitory effects toward either CYP2C9*1 or CYP2C19*1. These findings provided valuable information for a potentially toxic mechanism of DEHP and DBP on endocrine disruption and a useful guidance for safe and effective usage of drugs in patients with long-term DEHP and DBP exposure.

[Minocycline inhibits formalin-induced inflammatory pain and the underlying mechanism]

OBJECTIVE

To unravel the underlying mechanism of minocycline in formalin-induced inflammatory pain, and to investigate the effects of minocycline on synaptic transmission in substantia gela-tinosa (SG) neurons of rat spinal dorsal horn.

METHODS

Behavioral and immunohistochemistry experiments: 30 male Sprague-Dawley (SD) rats (3-5 weeks old) were randomly assigned to control (n=8 rats), model (n=8 rats), saline treatment model (n=6 rats) and minocycline treatment model (n=8 rats) groups. The control group was subcutaneously injected with normal saline on the right hindpaws. Acute inflammatory pain model was established by injecting 5% (volume fraction) formalin into the right hindpaws. The rats in the latter two groups received intraperitoneal injection of saline and minocycline 1 h before the formalin injection, respectively. The time of licking and lifting was recorded every 5 min within 1 h after the subcutaneous injection of normal saline or formalin for all the groups, which was continuously recorded for 1 h. One hour after the pain behavioral recording, the spinal cord tissue was removed following transcardial perfusion of 4% paraformaldehyde. The expression of c-Fos protein in spinal dorsal horn was observed by immunohistochemistry. Electrophysiological experiment: In vitro whole-cell patch-clamp recordings were performed in spinal cord parasagittal slices obtained from 26 male SD rats (3-5 weeks old). Two to five neurons were randomly selected from each rat for patch-clamp recording. the effects of minocycline, fluorocitrate and doxycycline on spontaneous excitatory postsynaptic currents (sEPSCs) or spontaneous inhibitory postsynaptic currents (sIPSCs) of SG neurons were investigated.

RESULTS

Compared with the control group, both the licking and lifting time and the expression of c-Fos protein in ipsilateral spinal dorsal horn of the model group were significantly increased. Intraperitoneal injection of minocycline largely attenuated the second phase of formalin-induced pain responses (t=2.957, P<0.05). Moreover, c-Fos protein expression was also dramatically reduced in both the superficial lamina (I-II) and deep lamina (III-IV) of spinal dorsal horn (t_I-II=3.912, t_III-IV=2.630, P<0.05). On the other side, bath application of minocycline significantly increased the sIPSCs frequency to 220%±10% (P<0.05) of the control but did not affect the frequency (100%±1%, t=0.112, P=0.951) and amplitude (98%±1%, t=0.273, P=0.167) of sEPSCs and the amplitude (105%±3%, t=0.568, P=0.058) of sIPSCs. However, fluorocitrate and doxycycline had no effect on the frequency [(99%±1%, t=0.366, P=0.099); (102%±1%, t=0.184, P=0.146), respectively] and amplitude [(98%±1%, t=0.208, P=0.253); (99%±1%, t=0.129, P=0.552), respectively] of sIPSCs.

CONCLUSION

Minocycline can inhibit formalin-induced inflammatory pain and the expression of c-Fos protein in spinal dorsal horn. These effects are probably due to its enhancement in inhibitory synaptic transmission of SG neurons but not its effect on microglial activation or antibiotic action.