Risk factors and survival analysis of human leukocyte antigen loss in relapsed acute myeloid leukaemia/myelodysplastic syndrome patients after allogeneic haematopoietic stem cell transplantation

To investigate the clinical characteristics and risk factors of specific human leukocyte antigen loss (HLA loss) in relapsed acute myeloid leukaemia (AML)/myelodysplastic syndrome (MDS) patients after allogeneic haematopoietic stem cell transplantation (allo-HSCT), and compare the responses of patients with HLA loss relapse with those without HLA loss (non-HLA loss) to different treatment regimens. Clinical data of traceable patients with AML/MDS after myeloablative allo-HSCT in our centre between January 2010 and June 2021, who experienced disease relapse after the transplantation, were collected. The patients were divided into the HLA loss relapse group and the non-HLA loss relapsed group based on HLA loss gene test findings by next-generation sequencing. The patients' median overall survival (OS) after the relapse were compared, and univariate and multivariate analyses were performed using the Kaplan-Meier survival curve and Cox proportional hazard model to explore the responses to different treatments after relapse. A total of 2359 patients were selected. Retrospective HLA gene loss gene detection was performed for the deoxyribonucleic acid in 179 relapsed patients, including 47 patients in the HLA loss group (27.2%), 126 patients in the non-HLA loss group (72.8%) and 6 patients were excluded due to a lack of confirmed results. There was no significant statistical difference in the baseline characteristics of patients between the two groups, but as to transplantation-related characteristics, the donor-recipient relationship and HLA mismatched loci were statistically different between the two groups (both p < 0.001). Multivariate Cox analysis showed that more HLA mismatched loci ≥3 (HR = 3.66; 95% CI: 1.61-8.31; p = 0.002), time (≤6 months) from HSCT to relapse (HR = 7.92; 95% CI: 3.35-18.74; p < 0.001) and donor chimerism (CD3) in bone marrow at relapse (HR = 1.02; 95% CI: 1.00-1.03; p = 0.036) were independent factors affecting HLA loss relapse. The ratio of negative conversion of FLT3-ITD or CEBPA mutation was significantly lower in patients with post-transplantation HLA loss relapse than in the non-HLA loss group (0.0% vs. 45.5%, p = 0.003; 0.0% vs. 80.0%, p = 0.035), with none of the patients with FLT3-ITD or CEBPA mutation turned negative in the HLA loss group. The number of gene mutations turned negative when relapse in the non-HLA loss group was remarkably higher than that in the HLA loss group (p = 0.001). Using donor lymphocyte infusion (DLI) could not prolong OS for the HLA loss group (p = 0.42). Nevertheless, second transplantation had a significant positive impact on OS in the HLA loss group (p = 0.017), although only five patients in the HLA loss group underwent second transplantation. However, patients in the non-HLA loss group using DLI had a relatively longer OS time than those without DLI (p = 0.017). Second transplantation could also prolong OS in the non-HLA loss group, but the effect was not as significant as in the HLA loss group (p = 0.053). In summary, HLA loss detection is essential for patients with recurrence after transplantation, especially for those with more HLA mismatched loci and non-sibling donor. Furthermore, the detection of HLA loss has a guiding role in choosing subsequent therapy when relapsed, as secondary transplantation is more suitable than DLI for those with HLA loss.

Generation of chimeric antigen receptor macrophages from human pluripotent stem cells to target glioblastoma

Background

Glioblastoma (GBM) is an aggressive brain tumor giving a poor prognosis with the current treatment options. The advent of chimeric antigen receptor (CAR) T-cell therapy revolutionized the field of immunotherapy and has provided a new set of therapeutic options for refractory blood cancers. In an effort to apply this therapeutic approach to solid tumors, various immune cell types and CAR constructs are being studied. Notably, macrophages have recently emerged as potential candidates for targeting solid tumors, attributed to their inherent tumor-infiltrating capacity and abundant presence in the tumor microenvironment.

Materials and methods

In this study, we developed a chemically defined differentiation protocol to generate macrophages from human pluripotent stem cells (hPSCs). A GBM-specific CAR was genetically incorporated into hPSCs to generate CAR hPSC-derived macrophages.

Results

The CAR hPSC-derived macrophages exhibited potent anticancer activity against GBM cells in vitro.

Conclusion

Our findings demonstrate the feasibility of generating functional CAR-macrophages from hPSCs for adoptive immunotherapy, thereby opening new avenues for the treatment of solid tumors, particularly GBM.

Identification of a venetoclax-resistance prognostic signature base on 6-senescence genes and its clinical significance for acute myeloid leukemia

Background

Satisfactory responses can be obtained for acute myeloid leukemia (AML) treated by Venetoclax (VEN)-based therapy. However, there are still quite a few AML patients (AMLs) resistant to VEN, and it is critical to understand whether VEN-resistance is regulated by senescence.

Methods

Here, we established and validated a signature for predicting AML prognosis based on VEN resistance-related senescence genes (VRSGs). In this study, 51 senescence genes were identified with VEN-resistance in AML. Using LASSO algorithms and multiple AML cohorts, a VEN-resistance senescence prognostic model (VRSP-M) was developed and validated based on 6-senescence genes.

Results

According to the median score of the signature, AMLs were classified into two subtypes. A worse prognosis and more adverse features occurred in the high-risk subtype, including older patients, non-de novo AML, poor cytogenetics, adverse risk of European LeukemiaNet (ELN) 2017 recommendation, and TP53 mutation. Patients in the high-risk subtype were mainly involved in monocyte differentiation, senescence, NADPH oxidases, and PD1 signaling pathway. The model's risk score was significantly associated with VEN-resistance, immune features, and immunotherapy response in AML. In vitro, the IC50 values of ABT-199 (VEN) rose progressively with increasing expression of G6PD and BAG3 in AML cell lines.

Conclusions

The 6-senescence genes prognostic model has significant meaning for the prediction of VEN-resistance, guiding personalized molecularly targeted therapies, and improving AML prognosis.

TFP5, a Peptide Derived from Cdk5 Activator p35, Protects Pancreatic β Cells from Glucose Toxicity

We studied the effect of TFP5 on MIN6 cells (cultured mouse islet β cells) treated with different concentrations of glucose (5 or 25 mM). The results were verified in C57BL/6J mice (control; n=12) and db/db mice with type 2 diabetes mellitus (n=12). To synthesize TFP5, peptide p5 (a derivative of p35 protein, activator of cyclin-dependent kinase 5, Cdk5) was conjugated with a FITC tag at the N-terminus and an 11-amino acid TAT protein transduction domain at the C-terminus. TFP5 was employed to inhibit Cdk5 activity and then to evaluate its efficiency in treating experimental type 2 diabetes mellitus. TFP5 effectively inhibited the pathological hyperactivity of Cdk5, enhanced insulin secretion, and protected pancreatic β cells from apoptosis in vitro and in vivo. In addition, TFP5 inhibited inflammation in pancreatic islets by reducing the expression of inflammatory cytokines TGF-β1, TNFα, and IL-1β. These novel data indicates that TFP5 is a promising candidate for treatment of type 2 diabetes mellitus.

Development of a scoring system for predicting primary resistance to venetoclax plus hypomethylating agents (HMAs) in acute myeloid leukemia patients

In recent years, one of the most promising advances in the treatment of acute myeloid leukemia (AML) is the combination of a hypomethylating agent (HMA) with the BCL2 inhibitor venetoclax (VEN). To better understand the key factors associated with the response of VEN plus HMA, 212 consecutive AML patients were retrospectively recruited to establish and validate a scoring system for predicting the primary resistance to VEN-based induced therapy. All AML patients were divided randomly into a training set (n = 155) and a validation set (n = 57). Factors were selected using a multivariate logistic regression model, including FAB-M5, myelodysplastic syndrome-secondary acute myeloid leukemia (MDS-sAML), RUNX1-RUNX1T1 and FLT3-ITD mutation (FLT3-ITDm). A nomogram was then constructed including all these four predictors. The nomogram both presented a good performance of discrimination and calibration, with a C-index of 0.770 and 0.733 in the training and validation set. Decision curve analysis also indicated that the nomogram was feasible to make beneficial decisions. Eventually a total scoring system of 8 points was developed, which was divided into three risk groups: low-risk (score 0-2), medium-risk (score 3-4), and high-risk (score 5-8). There was a significant difference in the nonremission (NR) rate of these three risk groups (22.8% vs. 60.0% vs. 77.8%, p < 0.001). After adjustment of the other variables, patients in medium- or high-risk groups also presented a worse event-free survival (EFS) than that in the low-risk group (hazard ratio [HR] = 1.62, p = 0.03). In conclusion, we highlighted the response determinants of AML patients receiving a combination therapy of VEN plus HMAs. The scoring system can be used to predict the resistance of VEN, providing better guidance for clinical treatment.

A Nomogram for Predicting Progression-free Survival in Patients with Endometrial Cancer

AIMS

Endometrial cancer is one of the most widely known gynaecological malignancies that lacks a prognostic prediction model. This study aimed to develop a nomogram to predict progression-free survival (PFS) in patients with endometrial cancer.

MATERIALS AND METHODS

Information for endometrial cancer patients diagnosed and treated from 1 January 2005 to 30 June 2018 was collected. The Kaplan-Meier survival analysis and multivariate Cox regression analysis were carried out to determine the independent risk factors and a nomogram was constructed by R based on analytical factors. Internal and external validation were then carried out to predict the probability of 3- and 5-year PFS.

RESULTS

In total, 1020 patients with endometrial cancer were included in the study and the relationship between 25 factors and prognosis was analysed. Postmenopause (hazard ratio = 2.476, 95% confidence interval 1.023-5.994), lymph node metastasis (hazard ratio = 6.242, 95% confidence interval 2.815-13.843), lymphovascular space invasion (hazard ratio = 4.263, 95% confidence interval 1.802-10.087), histological type (hazard ratio = 2.713, 95% confidence interval 1.374-5.356), histological differentiation (hazard ratio = 2.601, 95% confidence interval 1.141-5.927) and parametrial involvement (hazard ratio = 3.596, 95% confidence interval 1.622-7.973) were found to be independent prognostic risk factors; these factors were selected to establish a nomogram. The consistency index for 3-year PFS were 0.88 (95% confidence interval 0.81-0.95) in the training cohort and 0.93 (95% confidence interval 0.87-0.99) in the verification set. The areas under the receiver operating characteristic curve for the 3- and 5-year PFS predictions are 0.891 and 0.842 in the training set; the same conclusion also appeared in the verification set [0.835 (3-year), 0.803(5-year)].

CONCLUSIONS

This study established a prognostic nomogram for endometrial cancer that provides a more individualised and accurate estimation of PFS for patients, which will help physicians make follow-up strategies and risk stratification.

Identification and validation of a 7-genes prognostic signature for adult acute myeloid leukemia based on aging-related genes

To explore effects of aging-related genes (ARGs) on the prognosis of Acute Myeloid Leukemia (AML), a seven-ARGs signature was developed and validated in AML patients. The numbers of seven-ARG sequences were selected to construct the survival prognostic signature in TCGA-LAML cohort, and two GEO datasets were used independently to verify the prognostic values of signature. According to seven-ARGs signature, patients were categorized into two subgroups. Patients with high-risk prognostic score were defined as HRPS-group/high-risk group, while others were set as LRPS-group/low-risk group. HRPS-group presented adverse overall survival (OS) than LRPS-group in TCGA-AML cohort (HR=3.39, P<0.001). In validation, the results emphasized a satisfactory discrimination in different time points, and confirmed the poor OS of HRPS-group both in GSE37642 (HR=1.96, P=0.001) and GSE106291 (HR=1.88, P<0.001). Many signal pathways, including immune- and tumor-related processes, especially NF-κB signaling, were highly enriched in HRPS-group. Coupled with high immune-inflamed infiltration, the HRPS-group was highly associated with the driver gene and oncogenic signaling pathway of TP53. Prediction of blockade therapy targeting immune checkpoint indicated varied benefits base on the different ARGs signature score, and the results of predicted drug response suggested that Pevonedistat, an inhibitor of NEDD8-activating enzyme, targeting NF-κB signaling, may have potential therapeutic value for HRPS-group. Compared with clinical factors alone, the signature had an independent value and more predictive power of AML prognosis. The 7-ARGs signature may help to guide clinical-decision making to predict drug response, and survival in AML patients.

High FAAP24 expression reveals poor prognosis and an immunosuppressive microenvironment shaping in AML

BACKGROUND

As a core member of the FA complex, in the Fanconi anemia pathway, FAAP24 plays an important role in DNA damage repair. However, the association between FAAP24 and patient prognosis in AML and immune infiltration remains unclear. The purpose of this study was to explore its expression characteristics, immune infiltration pattern, prognostic value and biological function using TCGA-AML and to verify it in the Beat AML cohort.

METHODS

In this study, we examined the expression and prognostic value of FAAP24 across cancers using data from TCGA, TARGET, GTEx, and GEPIA2. To further investigate the prognosis in AML, development and validation of a nomogram containing FAAP24 were performed. GO/KEGG, ssGSEA, GSVA and xCell were utilized to explore the functional enrichment and immunological features of FAAP24 in AML. Drug sensitivity analysis used data from the CellMiner website, and the results were confirmed in vitro.

RESULTS

Integrated analysis of the TCGA, TARGET and GTEx databases showed that FAAP24 is upregulated in AML; meanwhile, high FAAP24 expression was associated with poor prognosis according to GEPIA2. Gene set enrichment analysis revealed that FAAP24 is implicated in pathways involved in DNA damage repair, the cell cycle and cancer. Components of the immune microenvironment using xCell indicate that FAAP24 shapes an immunosuppressive tumor microenvironment (TME) in AML, which helps to promote AML progression. Drug sensitivity analysis showed a significant correlation between high FAAP24 expression and chelerythrine resistance. In conclusion, FAAP24 could serve as a novel prognostic biomarker and play an immunomodulatory role in AML.

CONCLUSIONS

In summary, FAAP24 is a promising prognostic biomarker in AML that requires further exploration and confirmation.

Radiomics model and clinical scale for the preoperative diagnosis of silent corticotroph adenomas

OBJECTIVE

Silent corticotroph adenomas (SCAs) are a subtype of nonfunctioning pituitary adenomas that exhibit more aggressive behavior. However, rapid and accurate preoperative diagnostic methods are currently lacking.

DESIGN

The purpose of this study was to examine the differences between SCA and non-SCA features and to establish radiomics models and a clinical scale for rapid and accurate prediction.

METHODS

A total of 260 patients (72 SCAs vs. 188 NSCAs) with nonfunctioning adenomas from Peking Union Medical College Hospital were enrolled in the study as the internal dataset. Thirty-five patients (6 SCAs vs. 29 NSCAs) from Fuzhou General Hospital were enrolled as the external dataset. Radiomics models and an SCA scale to preoperatively diagnose SCAs were established based on MR images and clinical features.

RESULTS

There were more female patients (internal dataset: p < 0.001; external dataset: p = 0.028) and more multiple microcystic changes (internal dataset: p < 0.001; external dataset: p = 0.012) in the SCA group. MRI showed more invasiveness (higher Knosp grades, p ≤ 0.001). The radiomics model achieved AUCs of 0.931 and 0.937 in the internal and external datasets, respectively. The clinical scale achieved an AUC of 0.877 and a sensitivity of 0.952 in the internal dataset and an AUC of 0.899 and a sensitivity of 1.0 in the external dataset.

CONCLUSIONS

Based on clinical information and imaging characteristics, the constructed radiomics model achieved high preoperative diagnostic ability. The SCA scale achieved the purpose of rapidity and practicality while ensuring sensitivity, which is conducive to simplifying clinical work.

Comprehensive analysis of ERCC3 prognosis value and ceRNA network in AML

BACKGROUND

Acute myeloid leukemia (AML) is a hematological malignancy with high molecular and clinical heterogeneity, and is the most common type of acute leukemia in adults. Due to limited treatment options, AML is prone to relapse and has a poor prognosis. Excision repair cross-complementing 3 (ERCC3) is an important member of nucleotide excision repair (NER) that is overexpressed in types of solid cancers and potentially regarded as a prognostic factor. However, its role in AML remains unclear. The purpose of this study was to explore ERCC3 expression and functions in AML.

METHODS

The Cancer Genome Atlas (TCGA) and GEO (Gene Expression Omnibus) were used to test the accuracy of ERCC3 expression levels for AML diagnosis. Using online databases and R packages, we also explored the signaling pathway, epigenetic regulation, infiltration of immune cells, clinical prognostic value, and ceRNA network in AML.

RESULTS

Our results revealed that ERCC3 expression was increased in AML and that high ERCC3 expression had good value for disease-free survival and overall survival in AML patients who underwent allogeneic hematopoietic stem cell transplantation (allo-HSCT). We found that ERCC3 and co-expressed genes were mainly involved in chemical carcinogenesis/reactive oxygen species, ubiquitin-mediated protein degradation and oxidative phosphorylation. In addition, almost all the m⁶A-related coding genes (except GF2BP1) were positively associated with ERCC3 expression. We also constructed a ceRNA regulatory network containing ERCC3 in AML and identified 6 pairs of ceRNA networks, indicating that ERCC3 expression is regulated by a noncoding RNA system.

CONCLUSION

This study demonstrated that ERCC3 was overexpressed in AML and that high ERCC3 expression can be considered a biomarker conducive to allo-HSCT in AML patients.

Resveratrol promotes bone mass in ovariectomized rats and the SIRT1 rs7896005 SNP is associated with bone mass in women during perimenopause and early postmenopause

OBJECTIVE

This study aimed to examine the effects of SIRT1 agonist resveratrol on bone mass in ovariectomized (OVX) rats and the SIRT1 single-nucleotide polymorphism (SNP) rs7896005 on bone mass in women during menopause and early postmenopause.

METHODS

An animal experiment was conducted on rats that were sham-operated (SHAM), OVX or OVX and different administered doses of resveratrol. Serum markers and femur microstructure and staining were assessed. A cross-sectional study was conducted in women undergoing menopause. SIRT1 protein and SIRT1 SNP rs7896005 were evaluated.

RESULTS

OVX rats administered resveratrol, especially high doses, showed lower bone loss than OVX rats. Serum osteoprotegerin (OPG) and femur SIRT1, β-catenin and bone mineral density (BMD) were significantly increased, whereas receptor activator of NF-κB ligand (RANKL) was significantly decreased. Serum SIRT1 levels were significantly lower in women with low bone mass (p < 0.01). Women with the CA genotype of rs7896005 had lower bone mass than those with the CC genotype. The A allele showed a significant negative effect on bone loss risk (odds ratio = 3.48; p = 0.025).

CONCLUSIONS

Resveratrol stimulated SIRT1 expression and Wnt/β-catenin signaling to promote bone mass in rat femurs. Among women in perimenopause and early postmenopause, SIRT1 protected bone mass, and the A allele of SIRT1 rs7896005 was a risk factor for reduced bone mass.

LPCAT3 is a potential prognostic biomarker and may be correlated with immune infiltration and ferroptosis in acute myeloid leukemia: a pan-cancer analysis

BACKGROUND

Recent studies have highlighted the critical role of lysophosphatidylcholine acyltransferase 3 (LPCAT3) during cancer development. However, the abnormal expression and prognostic significance of pan-cancer have not been determined.

METHODS

We explored the expression level and prognostic value of LPCAT3 in 33 cancers by bioinformatics techniques, and comprehensively studied the biological function and immune infiltration based on the Cancer Genome Atlas (TCGA) and Genotype-Tissue Expression (GTEx) databases as well as many online websites.

RESULTS

LPCAT3 is significantly upregulated in many cancers, and it is associated with prognosis. Pan-cancer Cox regression analysis indicated that the high expression of LPCAT3 was associated with poor prognosis in acute myeloid leukemia (AML), lower-grade glioma (LGG), ovarian cancer (OV), and uveal melanoma (UVM), while better prognosis in kidney renal clear cell carcinoma (KIRC) (all P<0.05). Further analysis indicated that higher LPCAT3 expression in most cancers markedly decreased the infiltration of immune cells, except diffuse large B-cell lymphoma (DLBC), AML, LGG, stomach adenocarcinoma (STAD), and UVM. In contrast, the expression level of LPCAT3 was positively correlated with most immune checkpoints in colon adenocarcinoma (COAD), DLBC, LGG, liver hepatocellular carcinoma (LIHC), and UVM. Additionally, LPCAT3 expression was associated with tumor mutational burden (TMB) in 4 cancer types, while microsatellite instability (MSI) was in 3 cancer types. Functional enrichment analysis showed LPCAT3 upregulation was highly associated with lipid metabolism and ferroptosis processes. In addition, the result of prediction drug response suggested that B-cell lymphoma 2 (BCL2) inhibitors and Midostaurin may be a potential treatment option for AML with low-LPCAT3 expression.

CONCLUSIONS

LPCAT3 expression is increased in multiple cancers. Overexpression of LPCAT3 is associated with poor prognosis and tumor immune microenvironment in many cancers, especially in AML. Our results showed that the oncogene of LPCAT3 may serve as a potential prognostic biomarker and/or therapeutic target in AML patients.

Site-specific therapy in cancers of unknown primary site: a systematic review and meta-analysis

Background

Cancer of unknown primary site (CUP) is a term applied to characterize pathologically confirmed metastatic cancer with unknown primary tumor origin. It remains uncertain whether patients with CUP benefit from site-specific therapy guided by molecular profiling.

Patients and methods

A systematic search in PubMed, Web of Science, Embase, Cochrane Library, and ClinicalTrials.gov, and of conference abstracts from January 1976 to January 2021 was performed to identify studies investigating the efficacy of site-specific therapy on patients with CUP. The quality of included studies was evaluated using the Cochrane risk of bias tool and Newcastle–Ottawa scale. Eligible studies were weighted and pooled for meta-analysis. Hazard ratios (HRs) for overall survival (OS) and progression-free survival (PFS) were assessed to compare the efficacy of site-specific therapy with empiric therapy in patients with CUP. In addition, subgroup analyses were conducted.

Results

Five studies comprising 1114 patients were identified, of which 454 patients received site-specific therapy, and 660 patients received empiric therapy. Our meta-analysis revealed that site-specific therapy was not significantly associated with improved PFS [HR 0.93, 95% confidence interval (CI) 0.74-1.17, P = 0.534] and OS (HR 0.75, 95% CI 0.55-1.03, P = 0.069), compared with empiric therapy. However, during subgroup analysis significantly improved OS was associated with site-specific therapy in the high-accuracy predictive assay subgroup (HR 0.46, 95% CI 0.26-0.81, P = 0.008) compared with the low accuracy predictive assay subgroup (HR 0.93, 95% CI 0.75-1.15, P = 0.509). Furthermore, compared with patients with less responsive tumor types, more survival benefit from site-specific therapy was found in patients with more responsive tumors (HR 0.67, 95% CI 0.46-0.97, P = 0.037).

Conclusions

Our results suggest that site-specific therapy is not significantly associated with improved survival outcomes; however, it might benefit patients with CUP with responsive tumor types.

•

Studies evaluating the role of site-specific therapy guided by molecular profiling in CUP provided contradictory results.

•

Site-specific therapy is not significantly associated with improved survival outcomes in the overall CUP population.

•

Molecularly defined site-specific therapy may improve OS only when high-accuracy assays assign CUP to responsive tumor types.

Development of a Nomogram for Predicting the Cumulative Incidence of Disease Recurrence of AML After Allo-HSCT

Using targeted exome sequencing, we studied correlations between mutations at diagnosis and transplant outcomes in 332 subjects with acute myeloid leukemia (AML) receiving allotransplantation. A total of 299 patients (299/332, 90.1%) had at least one oncogenic point mutation. In multivariable analyses, pretransplant disease status, minimal residual disease (MRD) before transplantation (pre-MRD), cytogenetic risk classification, and TP53 and FLT3-ITD^{high ratio} mutations were independent risk factors for AML recurrence after allotransplantation (p < 0.05). A nomogram for the cumulative incidence of relapse (CIR) that integrated all the predictors in the multivariable model was then constructed, and the concordance index (C-index) values at 6, 12, 18, and 24 months for CIR prediction were 0.754, 0.730, 0.715, and 0.690, respectively. Moreover, calibration plots showed good agreements between the actual observation and the nomogram prediction for the 6, 12, 18, and 24 months posttransplantation CIR in the internal validation. The integrated calibration index (ICI) values were 0.008, 0.055, 0.094, and 0.136 at 6, 12, 18, and 24 months posttransplantation, respectively. With a median cutoff score of 9.73 from the nomogram, all patients could be divided into two groups, and the differences in 2-year CIR, disease-free survival (DFS), and overall survival (OS) between these two groups were significant (p < 0.05). Taken together, the results of our study indicate that gene mutations could help to predict the outcomes of patients with AML receiving allotransplantation.

The time-dependent effects of early-onset Epstein-Barr viremia on adult acute leukemia patients following allo-HSCT with ATG-containing MAC regimen

Epstein-Barr virus (EBV) viremia is a common complication after allogeneic hematopoietic stem cell transplantation (allo-HSCT). The purpose of this study was to evaluate the impacts of early-onset EBV viremia in acute leukemia (AL) patients who underwent allo-HSCT with anti-thymocyte globulin (ATG)-containing myeloablative conditioning (MAC) regimen. Two hundred and ninety-six patients were included between January 2013 and December 2015. In 126 patients (42.6%) who developed early-onset EBV viremia, with a median time of 48 (range 18~99) days after allo-HSCT. The cumulative incidence of EBV viremia at 30 and 90 days after allo-HSCT were 4.1 and 39.9%, respectively. Prognostic analysis showed that the adjusted overall survival in early-EBV^pos group was significantly lower than early-EBV^neg group within the first 26.7 months after allo-HSCT [hazard ratio (HR), 1.63, P = 0.012], but significantly higher than those afterward (after 26.7 months: HR 0.11, P = 0.035); for the adjusted event-free survival, early-EBV^pos group was significantly inferior in early-EBV^pos group within the first 10.8 months after transplantation (HR: 1.55, P = 0.042), and this adverse effect was not detected any more after 10.8 months (HR: 0.58, P = 0.107). Compared with early-EBV^neg group after adjusting by aGVHD and CMV viremia, HR for death from transplant-related mortality was 2.78-fold higher in patients with early-EBV viremia in piecewise constant Cox analysis (P = 0.006), and this adverse effect was not detected any more after the cut-point time (HR: 0.67, P = 0.361). No differences in terms of relapse and relapse mortality were observed between early-EBV^pos and early-EBV^neg group (P > 0.05). In conclusion, the impacts on transplant outcomes of early-EBV viremia were time-dependent, which may help to optimize management strategies for early-EBV viremia after allo-HSCT, especially in AL patients with ATG-containing MAC regimen.

Entamoeba gingivalis Exerts Severe Pathogenic Effects on the Oral Mucosa

The protozoan Entamoeba gingivalis colonizes the healthy oral mucosa with a prevalence of 15%. Colonization can be asymptomatic, and it is considered not pathogenic. However, it is able to invade lacerated oral mucosa, where it ingests fragments of live cells, suggesting pathogenous potential. Here, we characterized the transcriptomes of gingival cells after infection with E. gingivalis using RNA sequencing and observed pathogen interaction with the epithelial monolayer barrier by scanning electron microscopy. In epithelial and fibroblast cells, strongest differential expression showed gene set “chemokines and inflammatory molecules in myeloid cells” (area under the curve [AUC] = 0.9, effect size 5.15, adjusted P = 3.1 × 10⁻¹⁹) and “cell cycle and growth arrest” (AUC = 0.91, effect size = 4.56, adjusted P = 4.8 × 10⁻⁹), respectively. The most upregulated genes were TNF (fold change 430) and IL8 (fold change 359) in epithelial cells and ZN331 (fold change 18) in fibroblasts. We showed that E. gingivalis killed live epithelial cells by trogocytosis, demonstrating strong pathogenic potential.

A Constant-Force End-Effector With Online Force Adjustment for Robotic Ultrasonography

In this letter, we propose a novel constant-force end-effector (CFEE) to address current limitations in robotic ultrasonography. The CFEE uses a parallel, motor-spring-based solution to precisely generate constant operating forces over a wide range and enable the ultrasound (US) probe to adapt to the abdominal contours autonomously. A displacement measurement unit was developed to realize the acquisition of probe position and precise control of the operating force. Moreover, the operating force can be adjusted online to maintain safety and continuity of operation. Simulations and experiments were carried out to evaluate the performance. Results show that the proposed CFEE can provide constant forces of 4-12 N with displacements of 0-8 mm. The maximum relative error of force generation is 8.28%, and the accuracy and precision for displacement measurement are 0.29 mm and ±0.16 mm, respectively. Various operating forces can be adjusted online during the same operation. Ultrasound images acquired by the proposed CFEE are of equally good quality compared to a manual sonographer scan. The proposed CFEE would have potential further medical applications.

Donor-derived anti-CD19 CAR T cells compared with donor lymphocyte infusion for recurrent B-ALL after allogeneic hematopoietic stem cell transplantation

The efficacy and safety of donor-derived anti-CD19 CAR T cells vs DLI for the management of relapsed B-cell acute lymphoblastic leukemia (B-ALL) after allo-hematopoietic stem cell transplantation (HSCT) remain unclear. Thirteen B-ALL patients with relapsed after allo-HSCT and thus were treated with donor-derived anti-CD19 CAR T-cell (study group). Fifteen B-ALL patients relapsed after allo-HSCT and thus were treated with DLI (DLI group). The rates of MRD-negative complete remission (61.5%) in the study group were significantly higher than those in the DLI group (13.3%) (p = 0.02). The complete remission duration in study group and DLI group were median 8.0 months (range, 3-25 months) and 4.4 months (range, 1-25 months; p = 0.026), respectively. The overall survival of patients in the study group was superior to that of the DLI group: 9.5 months (range,3-25 months) versus 5.5 months (range, 1-25 months; p = 0.030). One patient with grade 1 acute graft-versus-host disease (aGVHD) was identified in the study group. While five (33.3%) patients in the DLI group developed grades III-IV aGVHD. Three patients (23.07%) developed grade 3 or 4 cytokine release syndrome in the study group. This study suggested that donor-derived anti-CD19 CAR T-cell therapy is promising, safe, and potentially effective for relapsed B-ALL after allo-HSCT and may be superior to DLI.

Donor CMV-specific cytotoxic T lymphocytes successfully treated drug-resistant cytomegalovirus encephalitis after allogeneic hematopoietic stem cell transplantation

Background: Cytomegalovirus (CMV) infection of the central nervous system (CNS) is a rare but life-threatening complication after allogeneic hematopoietic stem cell transplantation (allo-HSCT).Cases presentation: Two patients with drug-resistant CMV encephalitis after allo-HSCT were successfully treated with donor CMV-specific cytotoxic T lymphocytes (CTLs). In the first case, a 27-year-old male who received haploidentical transplantation to treat T-cell acute lymphoblastic leukemia (T-ALL), developed CMV encephalitis during the time of the ganciclovir maintenance treatment. After intravenous foscarnet and donor CMV-specific CTLs, CMV-DNA of CSF became undetectable and the abnormal signs of brain magnetic resonance imaging (MRI) were limited. Another case, a 57-year-old female with acute myeloid leukemia (AML) who underwent haploidentical transplantation, also developed CMV encephalitis during the maintenance treatment of the ganciclovir. After administering donor CMV-specific CTLs intrathecally, the CMV load of the CSF decreased.Conclusions: The intravenous/intratheca administration of donor CMV-specific CTLs may be a safe and effective treatment for CMV encephalitis, especially for patients who suffered from drug-resistant CMV infection.

Effect of Timely Lactate Measurement on In-hospital Mortality among Adults with Hypotension and Hyperlactatemia: An Observational Study on Two Cohorts.. [DOI: 10.21203/rs.3.rs-60524/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0]

Background: Whether patients presented with hypotension and hyperlactatemia can benefit from timely lactate measurement and further lactate-guide resuscitation were not fully understood.Methods: This was a retrospective observational study based on the data from the Medical Information Mart for Intensive Care (MIMIC)-III Database and the eICU Collaborative Research Database (eICU). Patients with hypotension (defined as a minimal systolic blood pressure ≤90 mm Hg or minimal mean arterial pressure ≤65 mm Hg or requiring any vasopressors support during the first 24 h after ICU admission) and hyperlactatemia (defined as an initial lactate level > 2.0 mmol/L after ICU admission) were eligible.The primary exposure was the timely lactate measurement, which was defined as an initial lactate level measured within 1 h after ICU admission. The primary outcome was in-hospital mortality. The statistical approaches included multivariate regression, propensity score matching (PSM) and an inverse probability of treatment weighing (IPTW) and causal mediation analysis (CMA) were utilized to elucidate the relationship between timely lactate measurement and in-hospital mortality. Results: A total of 9978 patients were identified, of which 4257 in MIMIC-III and 5721 in eICU. Timely lactate measurement was associated with lower risk-adjusted in-hospital mortality both in MIMIC (OR 0.70 (95%CI 0.58-0.85; p<0.001)) and eICU (OR 0.75 (95%CI 0.64-0.88; p<0.001)). Time to initial intravenous fluid (IVF) in MIMIC mediated 6.7% (95%CI 1.4%-38%; p<0.001) of the beneficial effect of timely lactate measurement (p<0.001 for average causal mediation effect (ACME)) in terms of in-hospital mortality. Finally, delayed initial lactate measurements are also associated an increased in-hospital mortality in MIMIC and eICU.Conclusions: Timely lactate measurement is associated with a lower risk-adjusted in-hospital mortality among patients with hypotension and hyperlactatemia, which was proportional mediated through shortening the time to IVF. Delay in initial lactate measurement showed a positive association with in-hospital mortality.

[Method of dietary nutritional status assessment and its application in cohort study of nutritional epidemiology]

Minimizing the burden on study subjects and assessing the general dietary nutritional status as accurately as possible are the basis of a nutritional epidemiological cohort study in the general population. While introducing the main dietary nutrition assessment methods, this paper manly describes the basic contents and principles for the development of food frequency questionnaire, and briefly illustrates the problems and solutions for the development of area specific food frequency questionnaires by taking the example of Tianjin Chronic Low-grade Systemic Inflammation and Health (TCLSIH) cohort study. Finally, discusses preliminarily the necessity and possibility of developing a national food frequency questionnaire.

Allogeneic Donor-Derived Anti-CD19 CAR T Cell Is a Promising Therapy for Relapsed/Refractory B-ALL After Allogeneic Hematopoietic Stem-Cell Transplantation

INTRODUCTION

Currently, effective and safe salvage therapies are limited among patients with relapsed acute lymphoblastic leukemia after allogeneic hematopoietic stem-cell transplantation (allo-HSCT). Anti-CD19 chimeric antigen receptor T (CAR T) cell is a promising treatment.

PATIENTS AND METHODS

We studied 11 patients with B-cell acute lymphoblastic leukemia that relapsed after allo-HSCT between September 2017 and October 2019. Patients were treated with a dose of single-infusion donor-derived anti-CD19 CAR T cells.

RESULTS

Eight patients (72.7%) experienced morphologic remissions. Seven (63.6%) experienced minimal residual disease-negative remission. The ongoing complete remission (CR) duration of 2 patients reached 22 months. The median overall survival was 9 months (range, 2-22 months). Only one patient with grade 1 acute graft-versus-host disease was observed. Two patients (18.2%) developed grade 3/4 cytokine release syndrome.

CONCLUSION

This prospective study showed allogeneic donor-derived anti-CD19 CAR T-cell therapy is an effective and safe salvage regimen for patients with relapsed/refractory B-cell acute lymphoblastic leukemia after allo-HSCT. Further randomized and multicenter investigations are needed to evaluate their potential role in relapsed acute lymphoblastic leukemia therapies after allo-HSCT.

Entamoeba gingivalis Causes Oral Inflammation and Tissue Destruction

A metagenomics analysis showed a strongly increased frequency of the protozoan Entamoeba gingivalis in inflamed periodontal pockets, where it contributed the second-most abundant rRNA after human rRNA. This observation and the close biological relationship to Entamoeba histolytica, which causes inflammation and tissue destruction in the colon of predisposed individuals, raised our concern about its putative role in the pathogenesis of periodontitis. Histochemical staining of gingival epithelium inflamed from generalized severe chronic periodontitis visualized the presence of E. gingivalis in conjunction with abundant neutrophils. We showed that on disruption of the epithelial barrier, E. gingivalis invaded gingival tissue, where it moved and fed on host cells. We validated the frequency of E. gingivalis in 158 patients with periodontitis and healthy controls by polymerase chain reaction and microscopy. In the cases, we detected the parasite in 77% of inflamed periodontal sites and 22% of healthy sites; 15% of healthy oral cavities were colonized by E. gingivalis. In primary gingival epithelial cells, we demonstrated by quantitative real-time polymerase chain reaction that infection with E. gingivalis but not with the oral bacterial pathogen Porphyromonas gingivalis strongly upregulated the inflammatory cytokine IL8 (1,900 fold, P = 2 × 10–4) and the epithelial barrier gene MUC21 (8-fold, P = 7 × 10–4). In gingival fibroblasts, we showed upregulation of the collagenase MMP13 (11-fold, P = 3 × 10–4). Direct contact of E. gingivalis to gingival epithelial cells inhibited cell proliferation. We indicated the strong virulence potential of E. gingivalis and showed that the mechanisms of tissue invasion and destruction are similar to the colonic protozoan parasite E. histolytica. In conjunction with abundant colonization of inflamed periodontal sites and the known resistance of Entamoeba species to neutrophils, antimicrobial peptides, and various antibiotics, our results raise the awareness of this protozoan as a potential and, to date, underrated microbial driver of destructive forms of periodontitis.

Combining gene variants with clinical characteristics improves outcome prediction in Chinese patients with myelodysplastic syndromes

Genetic variants have been identified in the majority of myelodysplastic syndromes (MDS) patients and have considerably influenced the diagnosis, classification, risk stratification and treatment of MDS. To explore the prognostic significance of genomic variants and build a new prognostic scoring model, we performed next-generation sequencing of 51 known genes in 499 Chinese patients with MDS. Ultimately, the TP53, GATA2, DNMT3A, age and the revised International Prognostic Scoring System (IPSS-R) risk stratification were included in a new Cox model and divided into three prognostic categories, and had a better prediction of overall survival. The C-index of the new prognostic scoring model (0.772) was clearly better than IPSS-R risk stratification (0.717), which was validated in 163 cases. Moreover, the new model was also suitable for the prediction of OS for patients undergoing allogeneic hematopoietic stem cell transplantation. The inclusion of genomic variants and age into the IPSS-R could improve prognostic algorithms for MDS patients.

Excessive daytime sleepiness with snoring or witnessed apnea is associated with handgrip strength: a population-based study

BACKGROUND

Sarcopenia is emerging as an important public health problem, and evidences have determined that poor sleep is associated with muscle strength, but the potential effects of excessive daytime sleepiness (EDS), snoring and witnessed apnea on handgrip strength have not been evaluated.

AIM

We aimed to examine the association between EDS, snoring, witnessed apnea and muscle strength in an adult population.

DESIGN

Cross-sectional study.

METHODS

This cross-sectional study comprised 19 434 adults. Handgrip strength was measured using a handheld digital dynamometer. EDS was assessed by Epworth Sleepiness Scale, snoring and witnessed apnea during sleep were reported through simple yes/no questions. Analysis of covariance was carried out to determine the association between EDS with snoring or witnessed apnea and muscle strength.

RESULTS

The means (95% confidence interval) for average handgrip strength/body weight (kg/kg) across symptoms categories were 0.396 (0.333-0.472), 0.393 (0.330-0.467), 0.396 (0.333-0.471) and 0.386 (0.325-0.460) (P < 0.0001), respectively. Similar results were observed with maximal handgrip strength/body weight (kg/kg).

CONCLUSIONS

Self-reported EDS accompanied with snoring or apnea is associated with lowest handgrip strength, independently of confounding factors. Whether improvement of EDS, snoring and apnea, can ameliorate age-associated decline in muscle strength warrants further studies.

Central Nervous System Complications after Allogeneic Hematopoietic Stem Cell Transplantation in Children

Central nervous system complications (CNSCs) after allogeneic hematopoietic stem cell transplantation (allo-HSCT) are common and may be a significant source of morbidity and mortality. We performed a retrospective study of 153 pediatric patients who underwent allo-HSCT to determine CNSC type, incidence, and impact on survival. A total of 34 patients (22.2%) developed CNSCs. The cumulative incidence of CNSCs at 100 days and 3 years was 18.30 and 22.73%, respectively. The most common CNSC was calcineurin inhibitor (CNI)-associated neurotoxicity (50.0%). Risk factors for CNSCs were the time from diagnosis to HSCT ≥4.8 months (p = 0.032) and the development of acute graft-versus-host disease (aGVHD) grade III-IV (p = 0.002). CNSCs after allo-HSCT negatively impacted overall survival (hazard ratio [HR] 1.97, p = 0.043) and nonrelapse mortality (HR 4.84, p < 0.001). In conclusion, CNSCs after allo-HSCT are associated with poor outcomes; patients with severe aGVHD and/or late transplantation should be given more attention.

OS8.1 A phase 0/2 clinical trial of a CDK4/6 inhibitor in aggressive meningioma patients

BACKGROUND

New approaches are urgently needed for aggressive meningiomas, which remain largely incurable. Forkhead Box M1 (FOXM1) has been identified as a master transcription factor in aggressive meningiomas and Cyclin D-dependent Kinases (CDK) are positive regulators of cell-cycle entry, promoting tumorigenesis through FOXM1 activation. We evaluated the tumor pharmacokinetics (PK), tumor pharmacodynamics (PD), and preliminary clinical response of ribociclib, a selective CDK4/6-inhibitor, in aggressive meningioma patients.

MATERIAL AND METHODS

Eight aggressive WHO Grade II/III meningioma patients with intact RB expression were enrolled and administered oral ribociclib daily (900mg) for 5 days prior to tumor resection. Plasma, tumor, and cerebrospinal fluid (CSF) samples were collected at 2, 8, or 24 h after the last dose. Total and unbound drug concentrations were determined using a validated LC-MS/MS method. PD effects, including RB and FoxM1 phosphorylation, were compared to matched archival tissue. Patients with PK and PD responses in tumor tissue, defined as unbound ribociclib concentration > 5-fold in vitro IC50 (0.04µM) and >20% decrease in pRB levels, respectively, were enrolled into an exploratory Phase 2 cohort.

RESULTS

The median CSF concentration of ribociclib was 0.25 µM. In tumor tissue, the median unbound ribociclib concentration was 1.36 µM and the median unbound tumor-to-plasma ratio was 5.34. Suppression of G1-to-S phase was inferred in tumors with declining FoxM1 phosphorylation (50%), RB phosphorylation (38%), and cellular proliferation (75%). Four patients demonstrated concurrent PK and PD responses and were graduated to continuous ribociclib therapy. At one year, two of these patients (one Grade II and one Grade III) demonstrate partial responses per RANO criteria.

CONCLUSION

Ribociclib achieves pharmacologically-active concentrations in aggressive meningioma tissue. Target modulation was demonstrated by a decrease in FOXM1-mediated tumor proliferation. Further investigation of ribociclib as a therapeutic strategy for aggressive meningiomas is warranted.

OS4.2 Phase 0 trial of Ceritinib in brain metastasis and recurrent glioblastoma

BACKGROUND

Ceritinib is an orally bioavailable, small molecule inhibitor for ALK/IGFR1/FAK, which are highly expressed in glioblastoma and brain metastases. Preclinical and clinical data suggest that ceritinib has activity in central nervous system (CNS) malignancies, but to date there is no direct evidence in patients. This study assessed the pharmacokinetics (PK) and pharmacodynamics (PD) of ceritinib in recurrent glioblastoma and brain metastasis patients.

MATERIALS AND METHODS

Three brain metastasis and seven glioblastoma patients with high expression of pSTAT5b/pFAK/pIGFR1 were enrolled and treated with oral ceritinib daily (750 mg) for 10 days prior to tumor resection. Plasma, tumor, and cerebrospinal fluid (CSF) samples were collected at ~ 4 and 24 h following the last dose. Total and unbound drug concentrations were determined using LC-MS/MS. PD response was assessed by immunohistochemical analysis of pALK, pFAK, pIGFR1, and pIRS1 staining in treated tumor and matched archival tissues.

RESULTS

Ceritinib was highly bound to human plasma protein (median fraction unbound (Fu), 1.4%) and to brain tumor tissue (median Fu, 0.073% and 0.14% in enhancing and non-enhancing regions respectively). There was a large interindividual variability in drug CNS penetration, with the median unbound concentrations in enhancing, non-enhancing, and CSF of 0.040, 0.006, and 0.012 µM, respectively. The median unbound tumor-to-plasma ratio was 2.44 and 0.33 in enhancing and non-enhancing areas, respectively. In one patient with brain metastasis, drug binding to enhancing tumor was significantly lower (Fu, 1.62%), resulting in a higher unbound drug tumor concentration and CSF concentration as compared to those in glioblastoma patients. In all patients, no changes in PD markers were detected.

CONCLUSION

Ceritinib is highly bound to plasma proteins and tumor tissues. Unbound drug concentrations achieved in brain metastasis and glioblastoma are unlikely sufficient for target modulation.

HMGA2 Modulates the TGFβ/Smad, TGFβ/ERK and Notch Signaling Pathways in Human Lens Epithelial-Mesenchymal Transition

BACKGROUND AND OBJECTIVE

Multiple signaling pathways coordinately promote epithelial-mesenchymal transition (EMT) in lens epithelial cells (LECs), where transforming growth factor beta (TGFβ)-mediated signaling plays a central role. But the mechanism of crosstalk among these pathways remains obscure. The objective of this study is to investigate the regulatory effect of the high mobility group protein A2 (HMGA2) on the signaling pathways in lens fibrosis.

METHODS

The human anterior capsulorhexis specimens were collected. The human SRA01/04 LEC line was cultured and treated with recombinant human TGFβ2 (5ng/ml). For inhibition of signaling pathways, a selective inhibitor SB431542, U0126 or DAPT was added to LECs respectively. The specific small interfering RNA (siRNA) were transfected to LECs for gene silence. The mRNAs expressions were measured by realtime PCR and the proteins expressions were determined by western blot and immunofluorescent staining.

RESULTS

HMGA2 and EMT markers α-smooth muscle actin (SMA), fibronectin (FN) and collagen type I (Col I) were overexpressed in human ASC specimens and TGFβ2 stimulated EMT in LECs. While blockage of EMT by a selective inhibitor of TGFβ/Smad, TGFβ/extracellular signal-regulated kinase (ERK) or Notch signaling pathway could significantly inhibited HMGA2 protein expression. And silence of HMGA2 by siRNA could significantly inhibit TGFβ2 induced expression of EMT markers including FN, Col I, collagen type IV (Col IV), key transcription factors Snail and Slug, and remarkably upregulate the epithelial markers E-cadherin and tight junction protein (ZO-1). In addition, silence of HMGA2 gene could abrogate TGFβ2 induced phosphorylation of Smad2, Smad3 as well as ERK1/2. Blockage of HMGA2 could also inhibit the upregulation of Jagged1, Notch2, and Notch3 induced by TGFβ2.

CONCLUSION

This study indicated that HMGA2 functions as a shared effector in TGFβ2- induced lens fibrosis, modulating the signaling network necessary for EMT in a positive feedback loop.

Prediction of acute GVHD and relapse by metabolic biomarkers after allogeneic hematopoietic stem cell transplantation

BACKGROUND

There are very few studies investigating metabolic biomarkers to predict acute graft-versus-host disease (aGVHD) after allogeneic hematopoietic stem cell transplantation (HSCT). Metabolic models can provide a framework for analyzing the information-rich omics data sets in this setting.

METHODS

Four hundred and fifty-six samples from one hundred and fourteen consecutive patients who underwent HSCT from January 2012 to May 2014 were collected for this study. The changes in serum metabolite levels were investigated using a gas chromatography-mass spectrometry-based metabolomics approach and underwent statistical analysis.

RESULTS

Significant metabolic changes were observed on day 7. The stearic acid/palmitic acid (SA/PA) ratio was effective in the diagnosis of grade II-IV aGVHD. Multivariate analysis showed that patients with high SA/PA ratios on day 7 after HSCT were less likely to develop II-IV aGVHD than patients with low SA/PA ratios (odds ratio [OR] = 0.06, 95% CI 0.02-0.18, P < 0.001). After the adjustment for clinical characteristics, the SA/PA ratio had no significant effect on overall survival (hazard ratio [HR] = 1.95, 95% CI 0.92-4.14, P = 0.08), and patients in the high SA/PA ratio group were significantly more likely to relapse than those in the low ratio group (HR = 2.26, 95% CI 1.04-4.91, P = 0.04).

CONCLUSION

Our findings suggest that the SA/PA ratio on day 7 after HSCT is an excellent biomarker to predict both aGVHD and relapse. The serum SA/PA ratio measured on day 7 after transplantation may improve risk stratification for aGVHD and relapse after allogeneic stem cell transplantation.

FUNDING

National Natural Science Foundation of China (81470346, 81773361), Priority Academic Program Development of Jiangsu Higher Education Institutions, Jiangsu Natural Science Foundation (BK20161204), Innovation Capability Development Project of Jiangsu Province (BM2015004), Jiangsu Medical Junior Talent Person award (QNRC2016707), and NIH (AI129582 and NS106170).

The effects of transboundary air pollution following major events in China on air quality in the U.S.: Evidence from Chinese New Year and sandstorms

Transboundary air pollution is a global environmental and public health problem including in the U.S., where pollution emissions from China, the largest emitter of anthropogenic air pollution in the world, can travel across the Pacific Ocean and reach places like California and Oregon. We examine the effects of transboundary air pollution following major events in China, specifically sandstorms, a natural-occurring source of air pollution, and Chinese New Year, a major 7-day holiday, on background air quality in the U.S. We focus on high elevation sites on the west coast between 2000 and 2013. We use regression analysis and a natural experiment to exploit the variation in the timing of these events in China, which are plausibly uncorrelated to other factors that affect air quality in China and the U.S. We find that sandstorms are associated with statistically significant increases in background coarse and fine particulate matter (PM) in the U.S., representing between 16 and 39% of average weekly PM levels. We also find Chinese New Year is associated with modest reductions in background air quality in the U.S., representing between 0.4 and 2.5% of PM levels. Findings are robust to different models and falsification tests. These results suggest that regression analysis could be a powerful tool to complement other, more widely used techniques in the environmental sciences that study this problem. This also has important implications for policymakers, who could track major sandstorms in China and prepare for possible increased foreign pollution emissions in the U.S.

The gut microbiota, bile acids and their correlation in primary sclerosing cholangitis associated with inflammatory bowel disease

Background

Patients with primary sclerosing cholangitis associated with inflammatory bowel disease (PSC-IBD) have a very high risk of developing colorectal neoplasia. Alterations in the gut microbiota and/or gut bile acids could account for the increase in this risk. However, no studies have yet investigated the net result of cholestasis and a potentially altered bile acid pool interacting with a dysbiotic gut flora in the inflamed colon of PSC-IBD.

Aim

The aim of this study was to compare the gut microbiota and stool bile acid profiles, as well as and their correlation in patients with PSC-IBD and inflammatory bowel disease alone.

Methods

Thirty patients with extensive colitis (15 with concomitant primary sclerosing cholangitis) were prospectively recruited and fresh stool samples were collected. The microbiota composition in stool was profiled using bacterial 16S rRNA sequencing. Stool bile acids were assessed by high-performance liquid chromatography tandem mass spectrometry.

Results

The total stool bile acid pool was significantly reduced in PSC-IBD. Although no major differences were observed in the individual bile acid species in stool, their overall combination allowed a good separation between PSC-IBD and inflammatory bowel disease. Compared with inflammatory bowel disease alone, PSC-IBD patients demonstrated a different gut microbiota composition with enrichment in Ruminococcus and Fusobacterium genus compared with inflammatory bowel disease. At the operational taxonomic unit level major shifts were observed within the Firmicutes (73%) and Bacteroidetes phyla (17%). Specific microbiota-bile acid correlations were observed in PSC-IBD, where 12% of the operational taxonomic units strongly correlated with stool bile acids, compared with only 0.4% in non-PSC-IBD.

Conclusions

Patients with PSC-IBD had distinct microbiota and microbiota-stool bile acid correlations as compared with inflammatory bowel disease. Whether these changes are associated with, or may predispose to, an increased risk of colorectal neoplasia needs to be further clarified.