Potential of radiomics analysis and machine learning for predicting brain metastasis in newly diagnosed lung cancer patients

AIM

To explore the potential of utilising radiomics analysis and machine-learning models that incorporate intratumoural and peritumoural regions of interest (ROIs) for predicting brain metastasis (BM) in newly diagnosed lung cancer patients.

MATERIALS AND METHODS

The study comprised 183 lung cancer patients (training cohort: n=146; validation cohort: n=37) whose radiomics features were extracted from plain computed tomography (CT) images of the primary lesion. Four machine-learning algorithms (logistic regression [LR], support vector machine [SVM], k-nearest neighbour algorithm [KNN], and random forest [RF]) were employed to develop predictive models. Model diagnostic performance was assessed through receiver operating characteristic (ROC) analysis, and clinical utility was evaluated using decision curve analysis (DCA). Finally, the radiomics model's generalisation ability was further validated in the prediction of metachronous brain metastasis (MBM).

RESULTS

After feature screening, 22 radiomics features were identified as highly predictive, of which nine were derived from the peritumour region. All four machine-learning models demonstrated predictive capability, with SVM showing superior efficiency and robustness. The area under the ROC curve (AUC) of SVM was 0.918 in the training cohort and 0.901 in the validation cohort. DCA indicated the highest net benefit. Furthermore, the time-dependent ROC curve exhibited predictive efficacy for MBM occurrence across 1-, 2-, and 3-year follow-up periods, with all AUC values exceeding 0.7.

CONCLUSION

The optimal SVM model integrating intratumoural and peritumoural radiomics features was confirmed and defined as an imaging biomarker for predicting BM in newly diagnosed lung cancer patients, underscoring its potential to significantly impact clinical diagnosis and treatment.

A novel mitochondria-related core gene signature to predict the prognosis and evaluate tumour microenvironment in CESC single-cell validation

Mitochondria and their related genes (MTRGs) are pivotal in the tumour microenvironment (TME) of cervical cancer, influencing prognosis and treatment response. This study developed a prognostic model using MTRGs to predict overall survival (OS) in cervical squamous cell carcinoma and endocervical adenocarcinoma (CESC), aiming for personalized therapy. Analysing 14 MTRGs like ISCU and NDUFA11 through techniques such as univariate Cox regression, we found that a low mitochondrial (MT) score is associated with better survival, while a high MT score predicts poorer outcomes. The TME score, particularly influenced by CD8 T cells, also correlates with prognosis, with a high score indicating favourable outcomes. The interplay between MT and TME subtypes revealed that the best prognosis is seen in patients with a low MT and high TME score. Our findings highlight the role of MTRGs as potential biomarkers and therapeutic targets in cervical cancer, offering a novel approach to improving patient outcomes through a more nuanced understanding of mitochondrial function and immune interactions within the TME. This model presents a promising avenue for enhancing the precision of prognostic assessments in CESC.

Uppermost global tree elevations are primarily limited by low temperature or insufficient moisture

The impact of anthropogenic global warming has induced significant upward dispersal of trees to higher elevations at alpine treelines. Assessing vertical deviation from current uppermost tree distributions to potential treeline positions is crucial for understanding ecosystem responses to evolving global climate. However, due to data resolution constraints and research scale limitation, comprehending the global pattern of alpine treeline elevations and driving factors remains challenging. This study constructed a comprehensive quasi-observational dataset of uppermost tree distribution across global mountains using Google Earth imagery. Validating the isotherm of mean growing-season air temperature at 6.6 ± 0.3°C as the global indicator of thermal treeline, we found that around two-thirds of uppermost tree distribution records significantly deviated from it. Drought conditions constitute the primary driver in 51% of cases, followed by mountain elevation effect which indicates surface heat (27%). Our analyses underscore the multifaceted determinants of global patterns of alpine treeline, explaining divergent treeline responses to climate warming. Moisture, along with temperature and disturbance, plays the most fundamental roles in understanding global variation of alpine treeline elevation and forecasting alpine treeline response to ongoing global warming.

NOD1 mediates interleukin-18 processing in epithelial cells responding to Helicobacter pylori infection in mice

The interleukin-1 family members, IL-1β and IL-18, are processed into their biologically active forms by multi-protein complexes, known as inflammasomes. Although the inflammasome pathways that mediate IL-1β processing in myeloid cells have been defined, those involved in IL-18 processing, particularly in non-myeloid cells, are still not well understood. Here we report that the host defence molecule NOD1 regulates IL-18 processing in mouse epithelial cells in response to the mucosal pathogen, Helicobacter pylori. Specifically, NOD1 in epithelial cells mediates IL-18 processing and maturation via interactions with caspase-1, instead of the canonical inflammasome pathway involving RIPK2, NF-κB, NLRP3 and ASC. NOD1 activation and IL-18 then help maintain epithelial homoeostasis to mediate protection against pre-neoplastic changes induced by gastric H. pylori infection in vivo. Our findings thus demonstrate a function for NOD1 in epithelial cell production of bioactive IL-18 and protection against H. pylori-induced pathology.

Recombinant Interferon α-2B Gel Combined with Lactobacillus as a Vaginal Capsule in Patients with Cervical High-Risk Human Papillomavirus

This study was performed to investigate the effects of Lactobacillus vaginal capsules combined with recombinant human interferon α-2b gel on clinical efficacy, vaginal microbial function indicators, vaginal microecological balance, inflammation levels, and drug safety in patients with persistent cervical high-risk human papillomavirus infection. Patients with human papillomavirus infection (n = 128) were randomly divided into control and observation groups of equal size. Patients in the control group were treated with recombinant human interferon α-2b gel alone. Patients in the observation group were treated with Lactobacillus vaginal capsules and human interferon α-2b gel. After treatment, the clinical efficiency, microbial function index, and human papillomavirus-DNA conversion rate of patients in the observation group were significantly higher than those in the control group. Further, pH, Nugent scores, human papillomavirus-DNA viral load, vaginal microecological dysregulation rate, and inflammation level were significantly lower than those in the control group. Lactobacillus vaginal capsules in combination with recombinant human interferon α-2b gel improved clinical outcomes and disease regression rates in patients with human papillomavirus infection, while also improving vaginal microecological balance and suppressing inflammatory responses.

[Pathological diagnosis of lung cancer based on deep transfer learning]

Objective: To establish an artificial intelligence (AI)-assisted diagnostic system for lung cancer via deep transfer learning. Methods: The researchers collected 519 lung pathologic slides from 2016 to 2019, covering various lung tissues, including normal tissues, adenocarcinoma, squamous cell carcinoma and small cell carcinoma, from the Beijing Chest Hospital, the Capital Medical University. The slides were digitized by scanner, and 316 slides were used as training set and 203 as the internal test set. The researchers labeled all the training slides by pathologists and establish a semantic segmentation model based on DeepLab v3 with ResNet-50 to detect lung cancers at the pixel level. To perform transfer learning, the researchers utilized the gastric cancer detection model to initialize the deep neural network parameters. The lung cancer detection convolutional neural network was further trained by fine-tuning of the labeled data. The deep learning model was tested by 203 slides in the internal test set and 1 081 slides obtained from TCIA database, named as the external test set. Results: The model trained with transfer learning showed substantial accuracy advantage against the one trained from scratch for the internal test set [area under curve (AUC) 0.988 vs. 0.971, Kappa 0.852 vs. 0.832]. For the external test set, the transferred model achieved an AUC of 0.968 and Kappa of 0.828, indicating superior generalization ability. By studying the predictions made by the model, the researchers obtained deeper understandings of the deep learning model. Conclusions: The lung cancer histopathological diagnostic system achieves higher accuracy and superior generalization ability. With the development of histopathological AI, the transfer learning can effectively train diagnosis models and shorten the learning period, and improve the model performance.

Genetic polymorphisms and cardiovascular outcomes in Chinese patients undergoing PCI and treated with clopidogrel and aspirin

Background

Genetic polymorphisms of key proteins involved in clopidogrel absorption, metabolism, and action may contribute to variability in platelet inhibition in patients undergoing percutaneous coronary intervention (PCI), but their impacts on cardiovascular outcomes remain unclear.

Purpose

To examine the associations between genetic polymorphisms and cardiovascular outcomes in Chinese patients undergoing PCI and treated with clopidogrel and aspirin.

Methods

This prospective cohort study consecutively enrolled 2,453 post-PCI patients treated with clopidogrel and aspirin. Adenosine diphosphate-induced platelet aggregation was measured by light transmission aggregometry. A total of 40 single nucleotide polymorphisms (SNPs) of 18 genes selected according to published studies were investigated using an improved multiplex ligation detection reaction technique. The primary outcome was major adverse cardiovascular event (MACE), the composite of cardiovascular death, non-fatal myocardial infarction (MI), and ischemic stroke within one year after PCI.

Results

We restricted the analyses to the first 1,452 patients who had finished one-year follow-up and complete data on genotyping and platelet aggregation. 44 (3.03%) patients suffered MACE. Among the 40 SNPs, only the A-allele carriers of CYP2C19*2 had a significant higher risk of MACE (adjusted HR 2.05; 95% CI, 1.01–4.19; p=0.048) and platelet aggregation than non-A-carriers after adjusting age, sex, MI presentation, and left ventricular ejection fraction. CYP2C19*3, CYP2B6 rs3745274, and PEAR1 rs12041331 variants were also significantly associated with platelet aggregation (all p<0.05) but not with MACE at 1 year.

Conclusion

About 54.2% of Chinese patients with PCI were A-allele carriers of CYP2C19*2, who face a two-fold higher risk of MACE than non-A-allele carriers in Chinese patients after PCI. It would help identify low clopidogrel responders and optimize antiplatelet therapy before drug administration.

Figure 1

Funding Acknowledgement

Type of funding source: Public grant(s) – National budget only. Main funding source(s): National Natural Science Funding of China

Recombinant Viral Capsid Protein L2 (rVL2) of HPV 16 Suppresses Cell Proliferation and Glucose Metabolism via ITGB7/C/EBPβ Signaling Pathway in Cervical Cancer Cell Lines

Purpose

Capsid protein L2 is the minor capsid protein of human papillomavirus 16 (HPV16). Although L2-based vaccines were developed, the therapeutic effect of recombinant viral capsid protein L2 (rVL2) was still to be illustrated.

Methods

We used glucose uptake and lactate production assay to verify the inhibitory effect of rVL2 on the glucose metabolism in cervical cancer cells. Secondly, we performed gene-chip assay, RT-PCR, and Western blot to determine the role of ITGB7/C/EBPβ signaling pathway in rVL2-mediated glucose metabolism in vitro. Finally, we used an animal model to verify the function of rVL2 in cervical cancer.

Results

We found that rVL2 reduced glucose uptake and lactate production levels in cervical cancer cells, which caused the inhibition of cell proliferation. rVL2 decreased the expression levels of key metabolic enzymes, including GLUT1, LDHA, and ALDOA, to affect cell metabolism in cervical cancer cells by inhibiting ITGB7/C/EBPβ signaling pathway in vitro and in vivo.

Conclusion

These results demonstrated the vital role of rVL2 in the glycolysis-induced cell growth and proliferation via suppressing ITGB7/C/EBPβ signaling axis.

A decrease in serum 1,5-anhydroglucitol levels is associated with the presence of a first-degree family history of diabetes in a Chinese population with normal glucose tolerance

AIM

This study aimed to investigate alterations in HbA_1c , glycated albumin (GA) and 1,5-anhydroglucitol (1,5-AG) in Chinese first-degree relatives of individuals with diabetes (FDR) in pursuit of an index for early screening of glucose metabolism disturbance.

METHODS

A total of 467 participants (age range: 20-78 years) with normal weight and normal glucose tolerance, as determined by a 75-g oral glucose tolerance test, were enrolled. HbA_1c was measured using high-performance liquid chromatography. Serum GA and 1,5-AG levels were determined by enzymatic methods. Serum insulin levels were measured using an electrochemiluminescence immunoassay.

RESULTS

The study population included 208 FDR and 259 non-FDR. Serum 1,5-AG levels were lower in FDR than that in non-FDR (20.4 ± 7.5 vs 23.8 ± 8.3 μg/ml, P < 0.001), but HbA_1c and GA levels did not differ between them (P = 0.835 and 0.469, respectively). Logistic regression analysis revealed an independent relationship between a first-degree family history of diabetes and reduced serum 1,5-AG levels (odds ratio = 0.944, P < 0.001). Multiple regression analysis showed that a first-degree family history of diabetes (β = -3.041, P < 0.001) and insulinogenic index (β = 0.081, P = 0.001) were independently associated with serum 1,5-AG levels.

CONCLUSION

In a Chinese population with normal glucose tolerance, serum 1,5-AG levels were lower among FDR, and serum 1,5-AG levels were independently associated with FDR status. For FDR, serum 1,5-AG levels were more sensitive than HbA_1c or GA levels to early-phase abnormality in glucose metabolism.

Vitamin A maintains the airway epithelium in a murine model of asthma by suppressing glucocorticoid-induced leucine zipper

BACKGROUND

The effects of glucocorticoids (GCs) on the repair of the airway epithelium in asthma are controversial, and we previously reported that the GC dexamethasone (Dex) inhibits the repair of human airway epithelial cells and that this process is mediated by glucocorticoid-induced leucine zipper (GILZ) through MAPK-ERK signaling in vitro. Vitamin A (VA) is involved in the regulation of the MAPK-ERK pathway but has not been widely supplied during asthma treatment. It is unclear whether VA attenuates the negative regulation of GILZ on the MAPK-ERK pathway and maintains airway epithelium integrity during asthma treatment.

METHODS

Female BALB/c mice were sensitized and challenged with ovalbumin (OVA) and subsequently treated with Dex, VA or intranasal inhalation of adenovirus sh-GILZ vectors. Indexes of airway epithelium integrity, including pathological alterations, pulmonary EGFR expression and airway hyperresponsiveness (AHR), were then measured. The expression of GILZ and key components of activated MAPK-ERK signals (p-Raf-1, p-MEK, and p-Erk1/2) were also detected.

RESULTS

Dex failed to relieve OVA-induced asthma airway epithelium injury, as assessed through H&E staining, EGFR expression and AHR. Moreover, in the OVA-challenged mice treated with Dex, GLIZ expression was increased, whereas the ratios of p-Raf-1/Raf-1, p-MEK/MEK and p-Erk1/2/Erk1/2 were significantly decreased. Further study indicated that GILZ expression was decreased and that the ratios of p-Raf-1/Raf-1, p-MEK/MEK and p-Erk1/2/Erk1/2 were up-regulated in the GILZ-silenced OVA-challenged mice and VA-fed OVA-challenged mice, independent of Dex treatment. The airway epithelium integrity of the OVA-challenged mice was maintained by treatment with both VA and Dex.

CONCLUSIONS

Vitamin A maintained the Dex-treated asthma airway epithelium via the down-regulation of GILZ expression and the activation MAPK-ERK signaling, and these effects might contribute to improving the effects of GC therapeutics on asthma.

Hotspot analyses indicate significant conservation gaps for evergreen broadleaved woody plants in China

Evergreen broadleaved woody plants (EBWPs) are dominant components in forests and savanna of the global tropic and subtropic regions. Southern China possesses the largest continuous area of subtropical EBWPs distribution, harboring a high proportion of endemic species. Hotspot and gap analyses are effective methods for analyzing the spatial pattern of biodiversity and conservation and were used here for EBWPs in China. Based on a distribution data set of 6,265 EBWPs with a spatial resolution of 50 × 50 km, we measured diversity of EBWPs in China using four indices: species richness, corrected weighted endemism, relative phylogenetic diversity, and phylogenetic endemism. According to the results based on 10% threshold, 15.73% of China’s land area was identified as hotspots using at least one diversity index. Only 2.14% of China’s land area was identified as hotspots for EBWPs by all four metrics simultaneously. Most of the hotspots locate in southern mountains. Moreover, we found substantial conservation gaps for Chinese EBWPs. Only 25.43% of the hotspots are covered by existing nature reserves by more than 10% of their area. We suggest to promote the establishment and management of nature reserve system within the hotspot gaps.

[Recombinant human tumor necrosis factor receptor type Ⅱ-IgG Fc fusion protein for treatment of occupational medicamentosa-like dermatitis induced by trichloroethylene]

Objective: To investigate the efficacy and safety of the recombinant human tumor necrosis factor receptor Ⅱ-IgG Fc fusion protein (rhTNFR: Fc, etanercept) for the treatment of occupational medicamentosa-like dermatitis induced by trichloroethylene (OMLDT) . Methods: In September 2011 to February 2016, 12 patients with OMLDT were treated with etanercept 25 mg, subcutaneous injection, twice per week, doubling of first dose. The course of treatment was 6 weeks. The drug eruption area and severity index (DASI) score, the proportion of patients achieving a 50%, 75% and 90% reduction in DASI (DASI50, DASI75, DASI90) and the serum level of TNF-α were used to assess the efficacy at different times. Adverse reactions were also recorded and evaluated. The results were statistically analyzed by nonparametric Friedman test and repetitive measurement ANOVA using the software SPSS19.0. Results: After 4 weeks treatment, the DASI score decreased form 56.33±7.02 to 0.50±0.91 (P<0.01) . The DASI50, DASI75 and DASI90 were all increased to 12 (100%) . The serum level of TNF-α decreased form (43.74±41.62) pg/ml to (3.03±0.47) pg/ml (P<0.01) . Statistically significant difference was observed from the above indexes. There were no adverse reactions in clinical application. Conclusion: Recombinant human tumor necrosis factor receptor Ⅱ-IgG Fc fusion protein may be a safe and effective drug in the treatment of OMLDT.

Expression of LRIG1 in pituitary tumor and its clinical significance

OBJECTIVE

To analyze the expression of leucine-rich and immunoglobulin-like domain gene1 (LRIG1) in pituitary tumor and its clinical significance.

PATIENTS AND METHODS

Patients were divided into two groups: hypophysoma group (n = 80) and normal group (normal brain tissue, n = 30). The immune tissue chemical streptavidin avidin-peroxidase was applied to detect the expression of LRIG1 of both groups and to analyze its relationship with the patients' prognosis.

RESULTS

The positive expression rate of LRIG1 in normal brain tissues was significantly higher than that in pituitary adenomas (100% vs. 53.8%) (p < 0.05). The positive expression rate of LRIG1 in pituitary tumors was not significantly related to age and gender, the difference was not statistically significant (p > 0.05). The positive expression rate of LRIGl in non-invasive pituitary adenomas was higher than that in invasive pituitary tumors (68.4% vs. 21.7%), the difference was statistically significant (p < 0.05). Cox multivariate survival analysis showed that LRIG1 can be used as an independent factor for prognosis evaluation. Meier survival analysis showed that the LRIG1 and pituitary tumor types were significantly associated with the prognosis of patients (p < 0.05).

CONCLUSIONS

LRIG1 was involved in the occurrence and development of pituitary tumor, the expression of LRIG1 can be used as an indicator for prognosis evaluation, and low expression indicated a poor prognosis.

Development of a cellular biosensor system for genotoxicity detection based on Trp53 promoter

OBJECTIVE

To develop a mouse cell biosensor system for the high-throughput genotoxicity detection of chemicals, such as environmental pollutants.

METHOD

We developed a novel reporter vector pGL4-GFP, wherein the firefly luciferase reporter gene in the pGL4.82 vector was replaced by the green fluorescent protein (GFP) gene from the pAcGFP1-N1 vector. To construct the reporter pGL4-p53-GFP (p53 promoter linked to GFP), a fragment containing the p53 gene promoter was generated by amplifying a region from -481 to +180 of mouse genomic DNA isolated from mouse tail tissue. We developed a mouse cell biosensor system for the high-throughput genotoxicity detection of new drugs by stably integrating the reporter plasmid of pGL4-p53-GFP into the mouse embryonic fibroblast cells. Various genotoxic agents were used to treat this biosensor system. The resulting fluorescence was directly observed under a fluorescence microscope, and the GFP protein level was measured through Western blot analysis.

RESULT

The biosensor system was treated with genotoxic agents, such as doxorubicin, cyclophosphamide, and benzo(a)pyrene. The GFP protein expression was significantly increased in cells exposed to genotoxic agents but negatively responded to the non-genotoxic agent dimethyl sulfoxide, thereby proving the specificity and sensitivity of the biosensor system.

CONCLUSION

This novel in vitro biosensor system can be especially useful in genotoxicity detection.

Randomised clinical trial evaluating best-corrected visual acuity and central macular thickness after 532-nm subthreshold laser grid photocoagulation treatment in diabetic macular oedema

Purpose

To compare best-corrected visual acuity (BCVA) and central macular thickness (CMT) after 532-nm subthreshold laser grid photocoagulation and threshold laser grid photocoagulation for the treatment of diabetic macular oedema (DME).

Patients and methods

Twenty-three patients (46 eyes) with binocular DME were enroled in this study. The two eyes of each patient were divided into a subthreshold photocoagulation group and a threshold photocoagulation group. The eyes of the subthreshold group underwent 532-nm patter scan laser system (PASCAL) 50% end point subthreshold laser grid photocoagulation therapy, whereas the threshold photocoagulation group underwent short-pulse grid photocoagulation with a 532-nm PASCAL system. BCVA and CMT were assessed in all patients before treatment, 7 days after treatment, and 1, 3, and 6 months after treatment.

Results

After grid photocoagulation, the mean BCVA improved in both the subthreshold group, and the threshold group, and the two groups did not differ statistically significantly from each other. Similarly, the macular oedema diminished in both groups after treatment, and the two groups did not differ statistically significantly from each other with regard to CMT.

Conclusion

Both 532-nm subthreshold laser grid photocoagulation and threshold laser grid photocoagulation can improve the visual acuity and reduce CMT in DME patients.

Preoperative serum CA125 is an independent predictor for prognosis in operable patients with non-small cell lung cancer

The role of serum CA125 and CEA in the prognosis of non-small cell lung cancer (NSCLC) remains controversial, especially in early stage patients, which need further clarification. Thus, in this study we carried out a large scale retrospective analysis of the prognostic value of CA125 and CEA in 645 patients with NSCLC, to explore their predictive value in the NSCLC. Patients who underwent curative surgical resection for NSCLC were from Zhejiang Cancer Hospital of China from 2006 to 2011. Microparticle enzyme immunoassay was used to measure preoperative serum CA125 and CEA. Univariate analyses and a multivariable proportional hazard Cox regression model were applied to assess the prognostic significance of the different covariates. Kaplan-Meier method was used to analyze survival curve. Both CA125 and CEA were correlated with stage, but also CA125 was different by grade, and CEA was related to histology. The Kaplan-Meier survival analysis showed that patients with elevated CA125 or CEA had unfavorable disease progression-free and overall survival time compared to those with normal CA125 or CEA. Furthermore, multivariate Cox analysis revealed that elevated CA125 had significantly higher risk for relapse (HR, 1.76; p=0.001) and death (HR, 1.80; p<0.001), but not for elevated CEA as relapse (HR, 1.06; p=0.736) and death (HR, 1.25; p= 0.119) both were statistically non significant. This study showed that both CA125 and CEA play important roles in disease progression while only CA125 as an independent predictive marker for prognosis in patients with NSCLC.

Study of Solid-plug Conveying in a Centrifugal Extruder

A new type of polymer processing machine, a centrifugal extruder, is introduced and its performance studied experimentally and analyzed theoretically. Calculations show that by means of appropriate choice of the geometrical parameters of the rotor drum and the rotor speed, the pressure of the solid polymer in the rotor drum can reach a value of several MPa. Theoretical analysis also shows that the most important factors influencing the solid conveying pressure in the rotor drum are the radius and slope angle of the rotor drum, the rotation speed of the rotor drum, the friction factor between the solid polymer and the drum surface, and the density of the polymer. An experimental rotor drum was designed in order to validate the mathematical model used for calculation of the solid conveying pressure in the rotor drum. The results of the experiments show good agreement with the theoretical predictions.

Cytotoxic T lymphocyte antigen 4 immunoglobulin modified dendritic cells attenuate allergic airway inflammation and hyperresponsiveness by regulating the development of T helper type 1 (Th1)/Th2 and Th2/regulatory T cell subsets in a murine model of asthma

T helper type 2 (Th2) and regulatory T cells (T(reg) ) have been postulated to have critical roles in the pathogenesis of allergic asthma. Cytotoxic T lymphocyte antigen 4 immunoglobulin (CTLA4Ig) gene-modified dendritic cells (DC-CTLA4Ig) have the potential to reduce Th2 cells and induce T(reg) cells. In the present study, we evaluated the therapeutic effects and potential mechanisms of the adoptive transfer of DC-CTLA4Ig into mice in an experimental model of asthma. BALB/c mice were sensitized with ovalbumin (OVA) and challenged with aerosolized OVA for 7 days. Just prior to the first challenge, DC-CTLA4Ig, DCs or DCs infected with DC-green fluorescent protein (GFP) were injected intravenously into mice. The administration of DC-CTLA4Ig reduced airway hyperresponsiveness, relieved asthmatic airway inflammation and decreased the numbers of esosinophils in the BALF in OVA-sensitized/challenged mice. In addition, DC-CTLA4Ig altered the balance of Th1/Th2 cytokine production in the lungs with increased interferon (IFN)-γ levels and decreased interleukin (IL)-4 levels, decreased the percentage of Th2 and increased both the percentage of Th1 and T(reg) cells in the lungs of OVA-sensitized/challenged mice. This research demonstrates that DC-CTL4Ig reduces airway hyperresponsiveness effectively and prevents airway inflammation in OVA-sensitized/challenged mice, which is due most probably to attenuated secretion of Th2 cytokines and increased secretion of Th1 cytokines in the local airway, and the correction of the pulmonary imbalance between Th1/Th2 cells and Th2/T(reg) cells.

Radical scavenging and xanthine oxidase inhibitory activity of phenolic compounds from Bridelia ferruginea stem bark

Bridelia ferruginea Benth. (Euphorbiaceae) is a subtropical medicinal plant widely used in traditional African medicine against various diseases, including rheumatic pains. Seven of its constituents (3-O-methylquercetin (1), 3,7,3′,4′-tetra-O-methylquercetin (rutisin, 2), myricetin (3), 3′,4′,5′-tri-O-methylmyricetin (ferrugin, 4), 3,3′,4′,5′-tetra-O-methylmyricetin (5), quercetin 3-O-glucoside (6), and a biflavanol gallocatechin-[4′-O-7]-epigallocatechin (7)) have been evaluated in-vitro in the xanthine-xanthine oxidase enzymatic system for inhibition of xanthine oxidase and radical scavenging activity. Results indicated that compounds 1, 3, 4 and 6 exhibited, at different levels, xanthine oxidase inhibiting and superoxide scavenging activity at micromolar concentrations, whereas compound 7 showed scavenging activity only. Compounds 2 and 5 were inactive in both cases. Study of the structure-activity relationship demonstrated that for flavonoids the xanthine oxidase inhibitory activity was reduced by methylation of the hydroxyl functionality at C-3 and in rings A and B. These results may partly explain and support the use of B. ferruginea stem bark for the treatment of rheumatic pains in traditional medicine.

Purified and sterilized magnetosomes from Magnetospirillum gryphiswaldense MSR-1 were not toxic to mouse fibroblasts in vitro

AIMS

To establish a criterion for measuring the purity of purified and sterilized magnetosomes from Magnetospirillum gryphiswaldense and to evaluate their toxicity for mouse fibroblasts in vitro.

METHODS AND RESULTS

The purification of magnetosomes involves disrupting bacterial cells with a French Press, washing directly with PBS buffer accompanied by treatment with low power ultrasonication, and using a magnet to collect the magnetosomes. Five characteristic peaks were displayed by Fourier-transform infrared spectroscopy (FT-IR), which was used to detect the quality of the purified magnetosomes, at 3273, 2921, 1735, 1645 and 1531 cm(-1). The purified magnetosomes showed no evidence of impurities when observed by transmission electron microscopy and energy disperse spectroscopy. The particles could be stored at -20 degrees C after lyophilization and treatment by gamma-rays. Purified and sterilized magnetosomes had no obvious negative effects on the viability of mouse fibroblasts by 3-(4,5-dimethylthiazolyl)-2,5-diphenyl-tetrazolium bromide assay.

CONCLUSIONS

Purified and sterilized magnetosomes were not toxic to mouse fibroblasts in vitro.

SIGNIFICANCE AND IMPACT OF THE STUDY

This study provides methods for evaluating the purity and safety of magnetosomes from M. gryphiswaldense. The magnetosomes have the potential to be used as novel drug or gene carriers for tumour therapy.

Analysis of the CDR3 region of alpha/beta T-cell receptors (TCRs) and TCR BD gene double-stranded recombination signal sequence breaks end in peripheral blood mononuclear cells of T-lineage acute lymphoblastic leukemia

Recently, numerous reports have highlighted the restriction of the CDR3 length of T-cell receptor (TCR) beta chain in T-cells infiltrating solid tumors and hematological malignancies. However, these studies ignored the restriction of CDR3 length of TCR alpha chain and few of them attempted to reveal the mechanisms of the oligo-clonal expansion of T cells in the tumors. The primary aims of this study were twofold to: (i) analyze the CDR3 length of TCR alpha and beta chain in peripheral blood mononuclear cells of T-lineage acute lymphoblastic leukemia (T-ALL); and (ii) discover the relationship between the clonality of T cells and the process of TCR rearrangement in peripheral T cells. To this end, we investigated the TCR BV and TCR AV family spectratypes of two T-ALL patients and healthy controls using the immunoscope spectratyping technique. We found that the spectratypes exhibited a Gaussian distribution in healthy controls. However, the TCR repertoires of the two patients were highly restricted in the number of different TCR BV and TCR AV family members present. Furthermore, we found that the peripheral blood mononuclear cells (PBMC) of two T-ALL patients had the recombination signal sequence (RSS) 5'- and 3'-breaks end in the TCR BD2 gene using a specialized ligation-mediated polymerase chain reaction, implying the ongoing recombination of the TCR beta gene. Analysis of the particular CDR3 length of TCR alpha/beta T cells might be helpful for further study of the individualized therapy of T-ALL. This information will also be helpful in exploring new immunological pathogenesis and facilitating the design of a T-ALL vaccine, as well as in improving our understanding of healthy human T-cell development.