Small extracellular vesicles facilitate epithelial-mesenchymal transition in chronic rhinosinusitis with nasal polyps via the miR-375-3p/QKI axis

BACKGROUND

Epithelial-mesenchymal transition (EMT) plays a crucial role in the pathogenesis of chronic rhinosinusitis with nasal polyps (CRSwNP). However, the involvement of small extracellular vesicles (sEVs) in EMT and their contributions to CRSwNP has not been extensively investigated.

METHODS

SEVs were isolated from nasal mucosa through ultracentrifugation. MicroRNA sequencing and reverse-transcription quantitative polymerase chain reaction were employed to analyze the differential expression of microRNAs carried by sEVs. Human nasal epithelial cells (hNECs) were used to assess the EMT-inducing effect of sEVs/microRNAs. EMT-associated markers were detected by western blotting and immunofluorescence. Dual-luciferase reporter assay was performed to determine the target gene of miR-375-3p. MicroRNA mimic, lentiviral, and plasmid transduction were used for functional experiments.

RESULTS

In line with the greater EMT status in eosinophilic CRSwNP (ENP), sEVs derived from ENP (ENP-sEVs) could induce EMT in hNECs. MiR-375-3p was elevated in ENP-sEVs compared to that in control and nonENP. MiR-375- 3p carried by ENP-sEVs facilitated EMT by directly targeting KH domain containing RNA binding (QKI) at seed sequences of 913-919, 1025-1033, and 2438-2444 in 3'-untranslated region. Inhibition of QKI by miR-375-3p overexpression promoted EMT, which could be reversed by restoration of QKI. Furthermore, the abundance of miR-375-3p in sEVs was closely correlated with the clinical symptom score and disease severity.

CONCLUSIONS

MiR-375-3p-enriched sEVs facilitated EMT by suppressing QKI in hNECs. The association of miR-375-3p with disease severity underscores its potential as both a diagnostic marker and a therapeutic target for the innovative management of CRSwNP.

Body mass index's effect on CRSwNP extends to pathological endotype and recurrence

BACKGROUND

Elevated body mass index (BMI) has been recognized as an important contributor to corticosteroid insensitivity in chronic rhinosinusitis with nasal polyps (CRSwNP). We aimed to delineate the effects of elevated BMI on immunological endotype and recurrence in CRSwNP individuals.

METHODOLOGY

A total of 325 patients with CRSwNP undergoing FESS were recruited and stratified by BMI. H&E staining was employed for histological evaluation. Characteristics of inflammatory patterns were identified by immunohistochemical staining. The predictive factors for recurrence were determined and evaluated by multivariable logistic regression analysis and the receiver operating characteristic (ROC) curves across all subjects and by weight group.

RESULTS

In all patients with CRSwNP, 26.15% subjects were classified as overweight/obese group across BMI categories and exhibited a higher symptom burden. The upregulated eosinophil/neutrophil-dominant cellular endotype and amplified type 2/ type 3 coexisting inflammation was present in overweight/obese compared to underweight/normal weight controls. Additionally, a higher recurrent proportion was shown in overweight/obese patients than that in underweight/normal weight cohorts. Multivariable logistic regression analysis identified BMI as an independent predictor for recurrence. The predictive capacity of each conventional parameter (tissue eosinophil and CLCs count, and blood eosinophil percentage) alone or in combination was poor in overweight/obese subjects.

CONCLUSIONS

Overweight/obese CRSwNP stands for a unique phenotype and endotype. Conventional parameters predicting recurrence are compromised in overweight/obese CRSwNP, and there is an urgent need for novel biomarkers that predict recurrence for these patients.

A Chemoproteomic Approach to Elucidate the Mechanism of Action of 6-Azasteroids with Unique Activity in Mycobacteria

By illuminating key 6-azasteroid-protein interactions in both Mycobacterium tuberculosis (Mtb) and the closely related model organism Mycobacterium marinum (Mm), we sought to improve the antimycobacterial potency of 6-azasteroids and further our understanding of the mechanisms responsible for their potentiation of the antituberculosis drug bedaquiline. We selected a newly developed 6-azasteroid analog and an analog reported previously (ACS Infect. Dis. 2019, 5 (7), 1239-1251) to study their phenotypic effects on Mtb and Mm, both alone and in combination with bedaquiline. The 6-azasteroid analog, 17β-[N-(4-trifluoromethoxy-diphenylmethyl)carbamoyl]-6-propyl-azaandrostan-3-one, robustly potentiated bedaquiline-mediated antimycobacterial activity, with a nearly 8-fold reduction in Mm bedaquiline minimal inhibitory concentration (85 nM alone versus 11 nM with 20 μM 6-azasteroid). This analog displayed minimal inhibitory activity against recombinant mycobacterial 3β-hydroxysteroid dehydrogenase, a previously identified target of several 6-azasteroids. Dose-dependent potentiation of bedaquiline by this analog reduced mycobacterial intracellular ATP levels and impeded the ability of Mtb to neutralize exogenous oxidative stress in culture. We developed two 6-azasteroid photoaffinity probes to investigate azasteroid-protein interactions in Mm whole cells. Using bottom-up mass spectrometric profiling of the cross-linked proteins, we identified eight potential Mm/Mtb protein targets for 6-azasteroids. The nature of these potential targets indicates that proteins related to oxidative stress resistance play a key role in the BDQ-potentiating activity of azasteroids and highlights the potential impact of inhibition of these targets on the generation of drug sensitivity.

Observation of high-energy neutrinos from the Galactic plane

The origin of high-energy cosmic rays, atomic nuclei that continuously impact Earth's atmosphere, is unknown. Because of deflection by interstellar magnetic fields, cosmic rays produced within the Milky Way arrive at Earth from random directions. However, cosmic rays interact with matter near their sources and during propagation, which produces high-energy neutrinos. We searched for neutrino emission using machine learning techniques applied to 10 years of data from the IceCube Neutrino Observatory. By comparing diffuse emission models to a background-only hypothesis, we identified neutrino emission from the Galactic plane at the 4.5σ level of significance. The signal is consistent with diffuse emission of neutrinos from the Milky Way but could also arise from a population of unresolved point sources.

[Correlation between contrast-enhanced ultrasound parameters and Crohn's disease activity]

Objective: By investigating the correlation between quantitative parameters of contrast enhanced ultrasound (CEUS) and commonly used activity assessment indicators of Crohn's disease (CD), and comparing the predictive power of laboratory inflammatory indicators with CEUS on Crohn's disease (CD), the significance of CEUS was evaluated. Methods: A case-control study. From October 2019 to December 2021, the clinical data of 67 patients with CD who were diagnosed by endoscopy and underwent contrast-enhanced ultrasonography were retrospectively analyzed in the First Affiliated Hospital with Nanjing Medical University, and their routine ultrasound and CEUS parameters, C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), fecal calprotectin (FC), Crohn's disease activity index (CDAI) and simplified endoscopic score for Crohn's disease (SES-CD) were collected. Using SES-CD as the standard, the patients were divided into a remission group and an active group, and the correlation of laboratory inflammatory indexes and contrast-enhanced ultrasound parameters with CDAI and SES-CD were evaluated. Besides, the ROC curve was used to analyze the predictive efficacy of each index on CD endoscopic activity. Results: A total of 67 patients were included in this study. According to the SES-CD score, there were 17 patients in the remission group and 50 patients in the active group. Except for the coefficient of the enhancement wash in slope and time to peak (TTP), the peak intensity (PI), area under the angiography curve, and laboratory inflammatory indexes were significantly different between the two groups (P<0.05), which also showed a moderate positive correlation with CDAI and SES-CD (P<0.05). ROC analysis showed that among the non-invasive indicators, PI and area under the angiography curve had the highest AUCs for predicting CD endoscopic activity, which were 0.912 and 0.891, respectively; with SES-CD taking >3 as the cut-off value, the corresponding sensitivities were 78.0% and 72.0%, with specificities of 100.0% and 94.1%, respectively. Conclusion: CEUS can objectively and repeatedly evaluate the disease activity of CD patients, and has great clinical application value, which can be used as a reliable imaging method for diagnosis and follow-up of patients with Crohn's disease.

Evidence for neutrino emission from the nearby active galaxy NGC 1068

A supermassive black hole, obscured by cosmic dust, powers the nearby active galaxy NGC 1068. Neutrinos, which rarely interact with matter, could provide information on the galaxy’s active core. We searched for neutrino emission from astrophysical objects using data recorded with the IceCube neutrino detector between 2011 and 2020. The positions of 110 known gamma-ray sources were individually searched for neutrino detections above atmospheric and cosmic backgrounds. We found that NGC 1068 has an excess of 79 − 20 + 22 neutrinos at tera–electron volt energies, with a global significance of 4.2σ, which we interpret as associated with the active galaxy. The flux of high-energy neutrinos that we measured from NGC 1068 is more than an order of magnitude higher than the upper limit on emissions of tera–electron volt gamma rays from this source.

Search for Unstable Sterile Neutrinos with the IceCube Neutrino Observatory

We present a search for an unstable sterile neutrino by looking for a resonant signal in eight years of atmospheric ν_{μ} data collected from 2011 to 2019 at the IceCube Neutrino Observatory. Both the (stable) three-neutrino and the 3+1 sterile neutrino models are disfavored relative to the unstable sterile neutrino model, though with p values of 2.8% and 0.81%, respectively, we do not observe evidence for 3+1 neutrinos with neutrino decay. The best-fit parameters for the sterile neutrino with decay model from this study are Δm_{41}^{2}=6.7_{-2.5}^{+3.9}  eV^{2}, sin^{2}2θ_{24}=0.33_{-0.17}^{+0.20}, and g^{2}=2.5π±1.5π, where g is the decay-mediating coupling. The preferred regions of the 3+1+decay model from short-baseline oscillation searches are excluded at 90% C.L.

[Application of locating supratrochlear artery and supraorbital artery in combined transfrontal and intranasal endoscopic approaches]

Objective: To investigate the localization methods of supratrochlear artery (STA) and supraorbital artery (SOA), and to explore the clinical benefit of locating nerve via accompanying vascular localization in combined transfrontal and intranasal endoscopic approaches. Methods: From June 2019 to May 2021, 14 patients, including 11 males and 3 females, aging from 18 to 69 years old, were underwent frontal sinus surgery through the combined transfrontal and intranasal endoscopic approaches in the Department of Otorhinolaryngology Head and Neck Surgery of the Third Affiliated Hospital of Sun Yat-sen University. Before the surgery, localization of STA and SOA was determined by color doppler flow imaging (CDFI), computerized topographic angiography (CTA) and contrast enhanced magnetic resonance angiography (CE-MRA) respectively, and the distances between STA and SOA from facial midline were measured on 28 eyebrows. The position of external incision was determined according to the preoperative localization of STA and SOA. The examination time, cost and postoperative complications of the three methods were recorded. The accuracy of localization at 14 sides was verified by the surgery. GraphPad Prism 8.3 software was used for statistical analysis. Results: STA and SOA could be located by CDFI, CTA and CE-MRA. There was no significant difference in the measurement of the distance between STA and SOA from the facial midline among 3 methods (all P>0.05). Determining the position of external incision according to the localization of STA and SOA could protect both the blood vessels and accompanying nerves. No postoperative complications such as numbness of the forehead skin occurred. The measurement time of CDFI, CTA and CE-MRA was 22.50 (15.75, 30.00), 30.00 (28.00, 34.25) and 48.00 (44.00, 52.75) min (M (Q₁, Q₃)), respectively (all P<0.05). CDFI incurred the lowest costs and took the shortest time. Conclusions: CDFI is an efficient and economic localization method. The localization of STA and SOA facilitates the precise selection of the position of external incision, protects the accompanying nerve and reduces postoperative complications.

Strong Constraints on Neutrino Nonstandard Interactions from TeV-Scale ν_{μ} Disappearance at IceCube

We report a search for nonstandard neutrino interactions (NSI) using eight years of TeV-scale atmospheric muon neutrino data from the IceCube Neutrino Observatory. By reconstructing incident energies and zenith angles for atmospheric neutrino events, this analysis presents unified confidence intervals for the NSI parameter ε_{μτ}. The best-fit value is consistent with no NSI at a p value of 25.2%. With a 90% confidence interval of -0.0041≤ε_{μτ}≤0.0031 along the real axis and similar strength in the complex plane, this result is the strongest constraint on any NSI parameter from any oscillation channel to date.

[Pathological characteristics and clinical prognosis of nodular sclerosis grade 2 of classic Hodgkin's lymphoma]

Objective: To investigate the pathological characteristics and clinical prognosis of nodular sclerosis grade 2 of classic Hodgkin's lymphoma (cHL-NS2) in our cancer center. Methods: A retrospective collection of 23 cases of cHL-NS2 admitted in Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College from July 2008 to April 2019 was performed. Fifty-five cases of nodular sclerosis grade 1 of classical Hodgkin's lymphoma (cHL-NS1) during the same period were selected as control group. Survival curves were plotted using the Kaplan-Meier method, and Cox regression model was used to analyze the influencing factors for survival. Results: The median age of 23 cases of cHL-NS2 was 30 years old. Five cases had extra nodal invasion, and 19 cases were Ⅰ-Ⅱ stage based on Ann Arbor system. The pathological morphology of cHL-NS2 showed that the lymph node structure was completely destroyed and was divided into nodules by thick collagen. The tumor cells in the nodules were abundant and proliferated in sheets. The boundaries between the tumor cells were not clear. The incidence of tumor necrosis in cHL-NS2 was 43.5% (10/23), which was significantly higher than 18.2% (10/55) in cHL-NS1 (P=0.040). The 3-year progression-free survival (PFS) rate of patients in the cHL-NS2 group was 58.1%, which was significantly lower than 89.7% in the cHL-NS1 group (P=0.002). In all of 78 cases, the 3-year PFS rate of patients who did not obtain complete response (CR) was 67.1%, which was significantly lower than 92.2% in patients who achieved CR (P=0.030). Multivariate Cox regression analysis demonstrated that both cHL-NS2 and failure to obtain CR by first-line treatment were independent indicators for short PFS time (P<0.05). Conclusions: In cHL-NS2, the morphology of tumor cells are diverse, and tumor necrosis can be easily found. Under the current first-line treatments of doxorubicin, bleomycin, vinblastine, and dacarbazine (ABVD) or bleomycin, etoposide, doxorubicin, cyclophosphamide, vincristine, procarbazine, and prednisone (BEACOPP), cHL-NS2 is an independent indicator for worse PFS.

Search for Relativistic Magnetic Monopoles with Eight Years of IceCube Data

We present an all-sky 90% confidence level upper limit on the cosmic flux of relativistic magnetic monopoles using 2886 days of IceCube data. The analysis was optimized for monopole speeds between 0.750c and 0.995c, without any explicit restriction on the monopole mass. We constrain the flux of relativistic cosmic magnetic monopoles to a level below 2.0×10^{-19}  cm^{-2} s^{-1} sr^{-1} over the majority of the targeted speed range. This result constitutes the most strict upper limit to date for magnetic monopoles with β≳0.8 and up to β∼0.995 and fills the gap between existing limits on the cosmic flux of nonrelativistic and ultrarelativistic magnetic monopoles.

Change of zinc mobilization and gene expression of key zinc transport proteins between the yolk sac membrane and liver of duck embryonic developing

Zinc (Zn) deposition in egg yolk is essential for the rapid growth and complete development of the avian embryo. Thus, it is crucial to obtain maximal Zn mobilization at an appropriate time during development in favor of the survival of avian embryos. The aim of this study was to study the developmental change of Zn mobilization and gene expression related to key Zn transport proteins between the yolk sac membrane and embryonic liver from the incubation d 17 (E17) to d 32 (E32) during duck embryonic developing. The weights of duck embryo, embryo without yolk sac, and embryonic liver increased as well as the yolk sac weight decreased linearly (P < 0.0001) when incubation day increased. The Zn concentration in the yolk sac did not change from E17 to E29 and only declined significantly from E29 to E32 of duck embryos, while hepatic Zn level decreased linearly as with the increased incubation time (P < 0.01). When the incubation day increased, the decreased Zn amount in the yolk sac and the increased Zn amount in the embryonic liver were observed (P < 0.0001). The calculated transfer-out rate of Zn in the yolk sac and transfer-in rate of Zn in livers were both increased from E23-26 to E29-32 (P < 0.01). Among E17, E23 and E29, the solute carrier family 39 member (ZIP) of ZIP10, ZIP13, and ZIP14 genes mRNA expressions were increased in yolk sac membrane but were decreased in the embryonic liver, while metallothionein 1 mRNA expression was increased both in the yolk sac membrane and liver (P < 0.05). In conclusion, yolk sac membrane and embryonic liver tissues displayed the similar developmental patterns of Zn mobilization and metallothionein 1 mRNA expression from E17 to E32 during duck embryonic developing. The appropriate time of the maximal rate of Zn mobilization were observed between E29 and E32 of duck embryo, associated with the significant changes of gene expression related to some key Zn transport proteins on E29 in yolk sac membrane and liver tissues.

Temperature Tides Across the Mid-Latitude Summer Turbopause Measured by a Sodium Lidar and MIGHTI/ICON

Local full diurnal coverage of temperature variations across the turbopause (~90-115 km altitude) is achieved by combining the nocturnal observations of a Sodium (Na) Doppler lidar on the Utah State University (USU) campus (41.7°N, 248.2°E) and NASA Michelson interferometer for global high-resolution thermospheric imaging (MIGHTI)/Ionospheric connection explorer (ICON) daytime observations made in the same vicinity. In this study, utilizing this hybrid data set during summer 2020 between June 12th and July 15th, we retrieve the temperature signatures of diurnal and semidiurnal tides in this region. The tidal amplitudes of both components have similar vertical variation with increasing altitude: less than 5 K below ~98 km but increase considerably above, up to 19 K near 104 km. Both experience significant dissipation near turbopause altitudes, down to ~12 K up to 113 km for the diurnal tide and ~13 K for the semidiurnal tide near 110 km. In addition, while the semidiurnal tidal behavior is consistent with the theoretical predictions, the diurnal amplitude is considerably larger than what is expected in the turbopause region. The tidal phase profile shows a dominance of tidal components with a long vertical wavelength (longer than 40 km) for the semidiurnal tide. On the other hand, the diurnal tide demonstrates close to an evanescent wave behavior in the turbopause region, which is absent in the model results and Thermosphere ionosphere mesosphere energetics and dynamics (TIMED)/Sounding of the atmosphere using broadband radiometry (SABER) observations.

[Activity comparison of humanized CD19 CAR-T cells with murine CD19 CAR-T on Nalm-6 cells and xenograft tumor model]

Objective: To compare the activity difference of the high affinity humanized CD19 chimeric antigen receptor (CAR)-T cells and murine CD19 CAR-T cells. Methods: Peripheral venous blood T cells from 8 healthy volunteers were collected and infected with humanized and murine CD19 CAR lentivirus. Human and murine CD19 CAR-T cells were prepared and cell proliferation was detected by cell counting kit-8 (CCK-8) method. The cytotoxicity of CD3(+) T cells, humanized and murine CD19 CAR-T cells to NALM-6 cells was detected by lactate dehydrogenase assay. Thirty BAL B/c nude mice transplanted with NALM-6 cells were randomly divided into 3 groups with 10 mice in each group and injected humanized CD19 CAR-T cells, mouse CD19 CAR-T cells and control CD3(+) T cell via tail vein, respectively. The proportion of NALM-6 cells in peripheral blood and the proportion of CD19 CAR-T cells in T cells from the vein of the inner canthus were detected by flow cytometry. The overall survival of BAL B/c nude mice was observed. Results: The proliferation of mouse and humanized CD19 CAR-T cells were (68.50±0.93)% and (80.63±1.41)%, respectively (t=20.353, P<0.001) after cultured in vitro for 24 hours, and were (91.38±1.41)% and (148.13±1.25)%, respectively (t=85.364, P<0.001) after cultured for 48 hours. When the effect to target ratio was 1∶1, there was no difference between the humanized and murine CD19 CAR-T cell group after co-culture for 24 hours (P=0.169), while the killing activity of humanized CD19 CAR-T cells against NALM-6 cells was higher than that of murine CD19 CAR-T cells (P<0.01) after 48 hours of co-culture. When the effect to target ratio was 4∶1, the cytotoxicity of humanized CD19 CAR-T cells against NALM-6 cells was higher than that of murine CD19 CAR-T cells in co-culture for 24 and 48 hours (P<0.01). On the seventh day of CD19 CAR-T cell therapy, the proportion of NALM-6 cells in the peripheral blood of BAL B/c nude mice decreased to the lowest level in the humanized CD19 CAR-T cell group and the murine CD19 CAR-T cell group. After 21 days, the proportion of NALM-6 cells in the murine CD19 CAR-T cell group was higher than that in the humanized CD19 CAR-T cell group (P(21 d)=0.001, P(28 d)<0.001, P(35 d)<0.001). The proportion of humanized and murine CD19 CAR-T cells in the peripheral blood reached the peaks after 7 days of therapy, and the proportion of humanized CD19 CAR-T cells was higher than that of murine CAR-T cells (P(7 d)=0.002). The CD19 CAR-T cells disappeared in the peripheral blood in the murine CD19 CAR-T cell group after 14 days of therapy, while in the humanized CD19 CAR-T cell group it disappeared after 21 days of therapy. The median survival of BAL B/c nude mice in the murine CD19 CAR-T cell group and the humanized CD19 CAR-T cell group was 42 days and 63 days, respectively (χ(2)=15.382, P<0.001). Conclusions: High affinity humanized CD19 CAR-T cells have stronger proliferation, higher cytotoxicity and longer survival time compared with those of murine CD19 CAR-T cells. The results indicate that the clinical efficacy of humanized CD19 CAR-T cells would be better than that of murine CD19 CAR-T cells.

Reductive Power Generated by Mycobacterium leprae Through Cholesterol Oxidation Contributes to Lipid and ATP Synthesis

Upon infection, Mycobacterium leprae, an obligate intracellular bacillus, induces accumulation of cholesterol-enriched lipid droplets (LDs) in Schwann cells (SCs). LDs are promptly recruited to M. leprae-containing phagosomes, and inhibition of this process decreases bacterial survival, suggesting that LD recruitment constitutes a mechanism by which host-derived lipids are delivered to intracellular M. leprae. We previously demonstrated that M. leprae has preserved only the capacity to oxidize cholesterol to cholestenone, the first step of the normal cholesterol catabolic pathway. In this study we investigated the biochemical relevance of cholesterol oxidation on bacterial pathogenesis in SCs. Firstly, we showed that M. leprae increases the uptake of LDL-cholesterol by infected SCs. Moreover, fluorescence microscopy analysis revealed a close association between M. leprae and the internalized LDL-cholesterol within the host cell. By using Mycobacterium smegmatis mutant strains complemented with M. leprae genes, we demonstrated that ml1942 coding for 3β-hydroxysteroid dehydrogenase (3β-HSD), but not ml0389 originally annotated as cholesterol oxidase (ChoD), was responsible for the cholesterol oxidation activity detected in M. leprae. The 3β-HSD activity generates the electron donors NADH and NADPH that, respectively, fuel the M. leprae respiratory chain and provide reductive power for the biosynthesis of the dominant bacterial cell wall lipids phthiocerol dimycocerosate (PDIM) and phenolic glycolipid (PGL)-I. Inhibition of M. leprae 3β-HSD activity with the 17β-[N-(2,5-di-t-butylphenyl)carbamoyl]-6-azaandrost-4-en-3one (compound 1), decreased bacterial intracellular survival in SCs. In conclusion, our findings confirm the accumulation of cholesterol in infected SCs and its potential delivery to the intracellular bacterium. Furthermore, we provide strong evidence that cholesterol oxidation is an essential catabolic pathway for M. leprae pathogenicity and point to 3β-HSD as a prime drug target that may be used in combination with current multidrug regimens to shorten leprosy treatment and ameliorate nerve damage.

Enzymatic β-Oxidation of the Cholesterol Side Chain in Mycobacterium tuberculosis Bifurcates Stereospecifically at Hydration of 3-Oxo-cholest-4,22-dien-24-oyl-CoA

The unique ability of Mycobacterium tuberculosis (Mtb) to utilize host lipids such as cholesterol for survival, persistence, and virulence has made the metabolic pathway of cholesterol an area of great interest for therapeutics development. Herein, we identify and characterize two genes from the Cho-region (genomic locus responsible for cholesterol catabolism) of the Mtb genome, chsH3 (Rv3538) and chsB1 (Rv3502c). Their protein products catalyze two sequential stereospecific hydration and dehydrogenation steps in the β-oxidation of the cholesterol side chain. ChsH3 favors the 22S hydration of 3-oxo-cholest-4,22-dien-24-oyl-CoA in contrast to the previously reported EchA19 (Rv3516), which catalyzes formation of the (22R)-hydroxy-3-oxo-cholest-4-en-24-oyl-CoA from the same enoyl-CoA substrate. ChsB1 is stereospecific and catalyzes dehydrogenation of the ChsH3 product but not the EchA19 product. The X-ray crystallographic structure of the ChsB1 apo-protein was determined at a resolution of 2.03 Å, and the holo-enzyme with bound NAD⁺ cofactor was determined at a resolution of 2.21 Å. The homodimeric structure is representative of a classical NAD⁺-utilizing short-chain type alcohol dehydrogenase/reductase, including a Rossmann-fold motif, but exhibits a unique substrate binding site architecture that is of greater length and width than its homologous counterparts, likely to accommodate the bulky steroid substrate. Intriguingly, Mtb utilizes hydratases from the MaoC-like family in sterol side-chain catabolism in contrast to fatty acid β-oxidation in other species that utilize the evolutionarily distinct crotonase family of hydratases.

[In vitro studies on the transfer of CAR into leukemia cells due to their residue in the autologous CAR-T cell preparation system for acute B-cell acute lymphoblastic leukemia]

Objective: To investigate the characteristics and cytotoxicity in vitro of the residual leukemia cells in the culture system that caused the accidental transfer of CD19 chimeric antigen receptor (CAR) into leukemia cells during the preparation of autologous CD19 CAR-T cells of relapsed/refractory B-cell acute lymphoblastic leukemia. Methods: ①Peripheral blood mononuclear cells (PBMC) of 30 patients with relapsed/refractory B-cell acute lymphoblastic anemia (R/R B-ALL) who accepted CD19 CAR-T cell therapy and six healthy volunteers were collected. ②The residual leukemia cells were analyzed by flow cytometry in the system after the PBMCs of R/R B-ALL patients were sorted by CD3 magnetic beads. ③ CD3(+) T cells from patients and healthy volunteers were transfected with CD19 CAR and CD22 CAR lentivirus to prepare CD19 CAR-T and CD22 CAR-T cells. ④The Nalm-6 cell line was resuscitated and the Nalm-6 cells with CD19 CAR lentivirus were transfected to prepare CD19 CAR-Nalm-6 cells. The patient's primary ALL cells were transfected with CD19 CAR lentivirus at the same time. ⑤The transfection rates were analyzed by flow cytometer, the cell proliferation was analyzed by the CCK-8 method, and the cell-killing activities were detected by the lactate dehydrogenase method. Results: ① Among the 30 R/R B-ALL patients who received CD19 CAR-T cell therapy, two patients had 2.04% and 3.32% residual leukemia cells in CD3(+) T cells. After 4 days in culture, the residual leukemia cells disappeared and could not be detected by a flow cytometer with prolonged cultivation in vitro. ② The proliferation of CD19 CAR-Nalm-6 cells was higher than that of the Nalm-6 cells. ③ The killing activity of the CD19 CAR-T cells on Nalm-6 cells was higher than that of the CD19 CAR-Nalm6 cells at a target ratio of 1∶1 on 24, 48, 72 h, respectively. The cytotoxicity of CD22 CAR-T cells on CD19 CAR-Nalm-6 cells was significantly higher than that of CD19 CAR-T cells. ④ The cytotoxicity of CD22 CAR-T alone on CD19 CAR-Nalm-6 cells was higher than that of CD19 CAR-T combined with CD22 CAR-T at the same target ratio. Conclusion: The residual leukemia cells in the culture system in the preparation of CD19 CAR-T cells may lead to the introduction of CD19 CAR into leukemia cells and results in the failure of the CD19 CAR-T cell therapy. Detecting the residual leukemia cells in the culture system via flow cytometry before transfection with CD19 CAR lentivirus is needed. Thus, CD22 CAR-T cell therapy could be used as one of the salvage treatments.

The pursuit of mechanism of action: uncovering drug complexity in TB drug discovery

Whole cell-based phenotypic screens have become the primary mode of hit generation in tuberculosis (TB) drug discovery during the last two decades. Different drug screening models have been developed to mirror the complexity of TB disease in the laboratory. As these culture conditions are becoming more and more sophisticated, unraveling the drug target and the identification of the mechanism of action (MOA) of compounds of interest have additionally become more challenging. A good understanding of MOA is essential for the successful delivery of drug candidates for TB treatment due to the high level of complexity in the interactions between Mycobacterium tuberculosis (Mtb) and the TB drug used to treat the disease. There is no single "standard" protocol to follow and no single approach that is sufficient to fully investigate how a drug restrains Mtb. However, with the recent advancements in -omics technologies, there are multiple strategies that have been developed generally in the field of drug discovery that have been adapted to comprehensively characterize the MOAs of TB drugs in the laboratory. These approaches have led to the successful development of preclinical TB drug candidates, and to a better understanding of the pathogenesis of Mtb infection. In this review, we describe a plethora of efforts based upon genetic, metabolomic, biochemical, and computational approaches to investigate TB drug MOAs. We assess these different platforms for their strengths and limitations in TB drug MOA elucidation in the context of Mtb pathogenesis. With an emphasis on the essentiality of MOA identification, we outline the unmet needs in delivering TB drug candidates and provide direction for further TB drug discovery.

[Clinical study of percutaneous vertebroplasty combined with (125)I seeds implantation in the treatment of patients with thoracic metastatic tumor complicated with posterior vertebral defect]

Objective: To analyze the safety and efficacy of percutaneous vertebroplasty combined with interstitial implantation (125)I of seeds (PVPI) in the treatment of thoracic vertebroplasty with posterior vertebra defect. Methods: A retrospective analysis of the clinical data of 64 patients with thoracic spine metastases admitted to Yunnan Cancer Hospital from November 2017 to May 2019 was conducted, including 32 patients with posterior vertebra defect (experimental group) and 32 cases without (control group). Forty-two vertebral bodies of 32 patients in the experimental group were treated with improved PVPI surgery, which performed with the secondary sealing method and inclined puncture needle injection bone cement rotary filling technology, to reduce leakage. The 54 vertebral bodies of 32 patients in control group underwent PVPI. The two groups of patients were followed up on the second day, one month, three months and six months after the operation, and the short-term efficacy, long-term efficacy and safety indicators of the two groups were compared. Results: All 64 patients successfully completed the surgical treatment. The visual analogue scores and Karnofsky scores of the experimental group and the control group were improved to varying degrees on the second day, 1 month, 3 months and 6 months after the operation. There was no statistically significant difference between the two groups (P>0.05). The amount of bone cement in the experimental group and control group was (2.36±0.20) ml and (2.39±0.17) ml, and the difference was not statistically significant (P=0.482). The amount of (125)I seed implantation was (30.63±0.91) and (32.56±0.68), respectively, the difference was not statistically significant (P=0.925). The partial response rates of the study group and the control group were 81.3% and 87.5%, the stable disease rates were 12.5% and 9.4%, the differences were not statistically significant (P>0.05). The median overall survival (mOS) of the study group was 13 months, and the median progression-free survival (mPFS) was 8 months. The mOS of the control group was 14 months, and the mPFS was 8 months. The differences were not statistically significant (P>0.05). In the experimental group, 6 (14.3%) vertebral bodies had cement leakage, of which 2 (4.8%) were cement leakage at posterior vertebra, 4 (9.5%) were paravertebral cement leakage. Seven (13.0%) paravertebral cement leakage occurred in the control group. There was no significant difference in bone cement leakage between the two groups (P=0.097). Bone cement leakage in both groups did not cause serious complications such as spinal cord injury and paraplegia. Conclusion: The application of PVPI in the treatment of thoracic metastatic tumor patients with posterior vertebra defect can acquire better clinical efficacy and safety through conduction of the improved intraoperative technology and paying more attention to the control of bone cement distribution and other issues.

Differentially expressed proteins identified by TMT proteomics analysis in children with verrucous epidermal naevi

BACKGROUND

Verrucous epidermal naevi (VEN) are benign skin tumours, considered keratinocytic epidermal naevi, that appear at birth or early childhood. VEN may display a range of appearances, depending on patient age. Although the number of studies regarding VEN is increasing, the exact mechanism of VEN is still unknown.

OBJECTIVES

The aim of this study was to analyse the changes in the expression of protein factors in lesions of VEN children by TMT labelling-based quantitative proteomics.

METHODS

A total of 8 children with VEN (5 for experiment and 3 for validation) and 8 healthy children (5 for experiment and 3 for validation) presented to the Department of Dermatology, the First Affiliated Hospital of Anhui Medical University, Boao Super Hospital, between January 2019 and November 2019. The lesions and lesion-adjacent tissues from children with VEN and naevus-adjacent normal skin tissues from children with pigmented naevi were defined as the VEN group, VENC group and C group, respectively. We performed a proteomics analysis to screen for differentially expressed proteins in the lesions of these individuals. We further performed Western blotting to validate the relative expression levels of nine targeted proteins in the validation group.

RESULTS

According to the proteomics results, a total of 4970 proteins were identified, and 4770 proteins were quantified. Among these proteins, 586 proteins were up- or downregulated at least 1.3-fold with a P-value < 0.05 (upregulated: 399, downregulated: 187) in lesions between the VEN group and the C group. These proteins played important roles in multiple biological functions, such as cornification, epidermal cell differentiation and neutrophil activation, and formed a complicated protein-protein interaction network. Of the 586 up- or downregulated proteins, nine were selected for further validation. According to Western blotting analysis results, the relative expression levels of Involucrin, NDUFA4, Loricrin, Keratin type II cytoskeletal 6A (Cytokeratin 6A), BRAF, Filaggrin, S100A7 and Desmocollin-3 were significantly upregulated in VEN children and may be associated with skin barrier dysfunction, epidermal cell overgrowth and differentiation, inflammation and immune and oxidative phosphorylation, which are involved in the pathogenesis of VEN.

CONCLUSIONS

According to TMT-based proteomics and Western blotting results, we identified eight noteworthy proteins, Involucrin, NDUFA4, Loricrin, Keratin type II cytoskeletal 6A, BRAF, Filaggrin, S100A7 and Desmocollin-3, that were upregulated in the lesions of VEN children and may be associated with the pathogenesis of VEN. Our findings provide new starting points for identifying precise pathogenic mechanisms or therapeutic targets for VEN.

eV-Scale Sterile Neutrino Search Using Eight Years of Atmospheric Muon Neutrino Data from the IceCube Neutrino Observatory

The results of a 3+1 sterile neutrino search using eight years of data from the IceCube Neutrino Observatory are presented. A total of 305 735 muon neutrino events are analyzed in reconstructed energy-zenith space to test for signatures of a matter-enhanced oscillation that would occur given a sterile neutrino state with a mass-squared differences between 0.01 and 100  eV^{2}. The best-fit point is found to be at sin^{2}(2θ_{24})=0.10 and Δm_{41}^{2}=4.5  eV^{2}, which is consistent with the no sterile neutrino hypothesis with a p value of 8.0%.

Characteristics of the Diffuse Astrophysical Electron and Tau Neutrino Flux with Six Years of IceCube High Energy Cascade Data

We report on the first measurement of the astrophysical neutrino flux using particle showers (cascades) in IceCube data from 2010-2015. Assuming standard oscillations, the astrophysical neutrinos in this dedicated cascade sample are dominated (∼90%) by electron and tau flavors. The flux, observed in the sensitive energy range from 16 TeV to 2.6 PeV, is consistent with a single power-law model as expected from Fermi-type acceleration of high energy particles at astrophysical sources. We find the flux spectral index to be γ=2.53±0.07 and a flux normalization for each neutrino flavor of ϕ_{astro}=1.66_{-0.27}^{+0.25} at E_{0}=100  TeV, in agreement with IceCube's complementary muon neutrino results and with all-neutrino flavor fit results. In the measured energy range we reject spectral indices γ≤2.28 at ≥3σ significance level. Because of high neutrino energy resolution and low atmospheric neutrino backgrounds, this analysis provides the most detailed characterization of the neutrino flux at energies below ∼100  TeV compared to previous IceCube results. Results from fits assuming more complex neutrino flux models suggest a flux softening at high energies and a flux hardening at low energies (p value ≥0.06). The sizable and smooth flux measured below ∼100  TeV remains a puzzle. In order to not violate the isotropic diffuse gamma-ray background as measured by the Fermi Large Area Telescope, it suggests the existence of astrophysical neutrino sources characterized by dense environments which are opaque to gamma rays.

[Maintenance therapy following CD19 CAR-T treatment for relapsed B-cell acute lymphoblastic leukemia after allogeneic hematopoietic stem cell transplantation]

Objective: This study aimed to evaluate the maintenance therapy following an anti-CD19-CAR T-cell therapy for a B-cell acute lymphoblastic leukemia (ALL) patient who relapsed after allogeneic hematopoietic cell transplantation (allo-HSCT) and investigate the effect of donor stem cells and donor T lymphocyte infusion on the amplification of CD19 CAR-T cells. Methods: One refractory B-ALL patient relapsed after murine CD19 CAR-T cell therapy followed by a sibling allo-HSCT. He underwent a humanized CD19 CAR-T cell therapy followed by donor stem cell and donor T lymphocytes infusions as maintenance therapy in our hospital. The level of cytokines, the proportion of CD19 CAR-T cell, the level of CAR19 DNA expression in the peripheral blood, and the proportion of leukemia cells and donor chimerism in the bone marrow were detected. Correspondingly, T lymphocytes from the C57 spleen were separated to modify the CD19 CAR lentivirus and refused into C57 mice, and after 14 days, the B lymphocytes from C57 mice were separated and refused into the same C57 mice. The CD19 CAR T cells, B cells, and CD19 CAR gene counts in the peripheral blood were evaluated at different time points. Results: ①The patient achieved a complete response (CR) 14 days after a humanized CD19 CAR-T therapy with grade 1 cytokine release syndrome (CRS) and restored a donor chimerism to 99.76%. ② Following the remission from humanized CD19 CAR-T therapy, the patient received a maintenance therapy of donor stem cell infusion. Mild graft-versus-host disease (GVHD) manifested 24 days after infusion with an increased proportion of CD19 CAR-T cells and an increased level of CAR19 DNA expression in the peripheral blood. It fell with the remission of GVHD. The patient maintained CR and 99.69% donor chimerism during this period. ③ Throughout the subsequent donor T lymphocytes maintenance therapy, mild GVHD surfaced12 days after infusion without an increased proportion of CD19 CAR-T cells and an increased level of CAR19 DNA expression in the peripheral blood. The patient maintained CR and 99.87% donor chimerism during this period. ④ In vivo experiments on C57 mice confirmed that the proportion of CD19 CAR-T cells and the level of CAR19 DNA expression were upregulated in mice following CAR-T cell infusion, accompanied by depletion of CD19(+) B lymphocyte. After infusion of CD19(+) B lymphocyte cells, an increased proportion of CD19 CAR-T cells and an increased level of CAR19 DNA expression in the peripheral blood were observed again. Conclusions: The infusion of donor stem cells and donor T lymphocytes could be used as a maintenance treatment after CD19 CAR-T cell therapy for B-ALL patients who relapsed after allo-HSCT. Infusion of donor stem cells induced an increased proportion of CD19 CAR-T cells and an increased level of CAR19 DNA expression with the occurrence of GVHD. It might lead to further elimination of minimal residual disease.

Post-translational Succinylation of Mycobacterium tuberculosis Enoyl-CoA Hydratase EchA19 Slows Catalytic Hydration of Cholesterol Catabolite 3-Oxo-chol-4,22-diene-24-oyl-CoA

Cholesterol is a major carbon source for Mycobacterium tuberculosis (Mtb) during infection, and cholesterol utilization plays a significant role in persistence and virulence within host macrophages. Elucidating the mechanism by which cholesterol is degraded may permit the identification of new therapeutic targets. Here, we characterized EchA19 (Rv3516), an enoyl-CoA hydratase involved in cholesterol side-chain catabolism. Steady-state kinetics assays demonstrated that EchA19 preferentially hydrates cholesterol enoyl-CoA metabolite 3-oxo-chol-4,22-diene-24-oyl-CoA, an intermediate of side-chain β-oxidation. In addition, succinyl-CoA, a downstream catabolite of propionyl-CoA that forms during cholesterol degradation, covalently modifies targeted mycobacterial proteins, including EchA19. Inspection of a 1.9 Å resolution X-ray crystallography structure of Mtb EchA19 suggests that succinylation of Lys132 and Lys139 may perturb enzymatic activity by modifying the entrance to the substrate binding site. Treatment of EchA19 with succinyl-CoA revealed that these two residues are hotspots for succinylation. Replacement of these specific lysine residues with negatively charged glutamate reduced the rate of catalytic hydration of 3-oxo-chol-4,22-diene-24-oyl-CoA by EchA19, as does succinylation of EchA19. Our findings suggest that succinylation is a negative feedback regulator of cholesterol metabolism, thereby adding another layer of complexity to Mtb physiology in the host. These regulatory pathways are potential noncatabolic targets for antimicrobial drugs.

Environmental enrichment prevents chronic stress-induced brain-gut axis dysfunction through a GR-mediated mechanism in the central nucleus of the amygdala

BACKGROUND

Cognitive behavioral therapy (CBT) improves quality of life of patients with irritable bowel syndrome (IBS), a disorder characterized by chronic visceral pain and abnormal bowel habits. Whether CBT can actually improve visceral pain in IBS patients is still unknown. The aim of this study is to evaluate whether environment enrichment (EE), the animal analog of CBT, can prevent stress-induced viscero-somatic hypersensitivity through changes in glucocorticoid receptor (GR) signaling within the central nucleus of the amygdala (CeA).

METHODS

Rats were housed in either standard housing (SH) or EE for 7 days before and during daily water avoidance stress (WAS) exposure (1-h/d for 7 days). In the first cohort, visceral and somatic sensitivity were assessed via visceromotor response to colorectal distention and von Frey Anesthesiometer 24 hous and 21 days after WAS. In another cohort, the CeA was isolated for GR mRNA quantification.

KEY RESULTS

Environment enrichment for 7 days before and during the 7 days of WAS persistently attenuated visceral and somatic hypersensitivity when compared to rats placed in SH. Environment enrichment exposure also prevented the WAS-induced decrease in GR expression in the CeA.

CONCLUSION & INFERENCES

Pre-exposure to short-term EE prevents the stress-induced downregulation of GR, and inhibits visceral and somatic hypersensitivity induced by chronic stress. These results suggest that a positive environment can ameliorate stress-induced pathology and provide a non-pharmacological therapeutic option for disorders such as IBS.

Self-made Salmonella Pullorum agglutination antigen development and its potential practical application

Pullorum disease caused by Salmonella Pullorum is one of the most important infectious diseases in the poultry industry worldwide, which leads to serious economic losses in many developing countries because of its high mortality rate in young chicks. The traditional slide agglutination test with low cost, fast reaction, and on-site detection has been widely used in the diagnosis of Pullorum disease. However, in practice, the test performance is with the disadvantages of false positive results and unstable detection results. In this paper, we developed self-made agglutination antigens prepared by local isolates in the poultry farm and compare the detection performance with commercial agglutination antigens (China Institute of Veterinary Drug Control) and Group D Salmonella ELISA kit (BioChek UK Ltd). The results of detecting 200 serum samples indicated that the consistency of commercial agglutination antigen detecting in 2 times was only 79.5%. Using the ELISA kit as the reference method, the commercial agglutination antigen detecting results of the Kappa test were only moderately consistent (0.58 ∼ 0.59). Meanwhile, positive and total coincidence rates of the self-made agglutination antigen test with more reliable repeat could reach 97.4 and 88%, respectively, and the result of Kappa test was highly consistent (0.75). The Receiver Operating Characteristic curve analysis clarified that the area under the receiver-operating-characteristic curve values of self-made and commercial agglutination antigen tests could reach 0.861 and 0.804, respectively. These results were coincident when detecting known positive serum from the infected chickens. It's worth mentioning that the visible positive reaction of self-made agglutination antigen test appeared faster and stronger than commercial antigen test. In conclusion, self-made Salmonella Pullorum agglutination antigen developed in this study was much better than commercial agglutination antigen and is expected to be a valuable tool in the diagnosis of the epidemiology of Salmonella Pullorum.

[Etiology and clinical features of primary adrenal insufficiency]

Objective: To summarize the etiology of primary adrenal insufficiency (PAI) and analyze its clinical features. Methods: A retrospective analysis was performed in the Department of Endocrinology, Peking Union Medical College Hospital from October 1981 to June 2019. Patients with PAI as the first symptom were enrolled. The etiology of PAI was analyzed and the clinical characteristics was also summarized. Results: A total of 131 patients with PAI were enrolled, including 87 males and 44 females (57 adolescents, and 74 adults). The age ranged from 0 to 73 years. The primary cause of PAI in adolescents was genetic defects (52.6%, 30/57), in which congenital adrenal dysplasia caused by DAX1 gene deficiency accounted for 50.0% (15/30), followed by autoimmunity (22.8%, 13/57). The primary cause of adult PAI was infection (58.1%, 43/74), of which tuberculosis accounted for the majority (93.0%, 40/43), and autoimmune adrenalitis accounted for 19.0% (14/74). Compared with the tuberculosis group, female patients were more common, and the onset age was younger, the plasma cortisol, serum sodium, fasting blood glucose, creatinine and aldosterone were lower (all P<0.05), and serum potassium and renin levels were higher in the autoimmune adrenalitis group (both P<0.05). Conclusions: In the current study, the proportion of PAI caused by infection in the adult group was higher than that in the adolescent group. The most common cause of adult PAI was tuberculosis infection. The most common cause of childhood PAI was genetic defects. Autoimmune damage to the adrenal glands may be more severe than tuberculosis infection.

[Analysis of the efficacy and influencing factors of nilotinib or dasatinib as second- or third-line treatment in patients with chronic myeloid leukemia in the chronic phase and accelerated phase]

目的

分析二代酪氨酸激酶抑制剂（TKI）尼洛替尼和达沙替尼作为二三线药物治疗慢性髓性白血病（CML）慢性期（CP）和加速期（AP）患者的治疗反应和预后，以及相关影响因素。

方法

回顾性分析2008年1月至2018年11月北京大学人民医院收治的一二线TKI治疗失败并接受尼洛替尼或达沙替尼作为二三线治疗的CML-CP和AP患者资料。

结果

共收集183例尼洛替尼和达沙替尼作为二线治疗和43例尼洛替尼和达沙替尼作为三线治疗的CML-CP或AP患者。二线TKI治疗患者中，中位随访21（1~135）个月，完全血液学反应（CHR）率为80.4%，完全细胞遗传学反应（CCyR）率为56.3%，主要分子学反应（MMR）率为38.3%，3年疾病无进展生存（PFS）和总生存(OS)率分别为78.7%和93.1%。二线TKI治疗中，Sokal积分为高危、女性、一线TKI治疗期间获得最佳反应<CHR、诊断CML距转换二线TKI治疗时间≥18个月、二线TKI治疗前为AP/血液学耐药、二线TKI治疗前未检测出BCR-ABL特殊突变、二线治疗中发生≥3级血液学不良反应是获得细胞遗传学或分子学反应或PFS的不利影响因素。三线TKI治疗患者中，中位随访6（3~129）个月，CHR率为95.7%，CCyR率为29.3%，MMR率为18.6%，2年PFS和OS率分别为66.8%和93.8%。三线TKI治疗中，诊断距一线TKI治疗时间≥6个月、二线TKI治疗期间未获得细胞遗传学反应、诊断距三线TKI治疗时间≥60个月或转换治疗前疾病分期为AP患者获得治疗反应的比例显著降低或预后不良。

结论

尼洛替尼和达沙替尼作为二三线药物可以有效治疗TKI耐药的CML-CP和AP患者，前次TKI治疗期间获得的最佳反应、换药前疾病分期和本次TKI治疗中是否发生≥3级血液学不良反应等因素影响治疗结果。

IpdE1-IpdE2 Is a Heterotetrameric Acyl Coenzyme A Dehydrogenase That Is Widely Distributed in Steroid-Degrading Bacteria

Steroid-degrading bacteria, including Mycobacterium tuberculosis (Mtb), utilize an architecturally distinct subfamily of acyl coenzyme A dehydrogenases (ACADs) for steroid catabolism. These ACADs are α₂β₂ heterotetramers that are usually encoded by adjacent fadE-like genes. In mycobacteria, ipdE1 and ipdE2 (formerly fadE30 and fadE33) occur in divergently transcribed operons associated with the catabolism of 3aα-H-4α(3'-propanoate)-7aβ-methylhexahydro-1,5-indanedione (HIP), a steroid metabolite. In Mycobacterium smegmatis, ΔipdE1 and ΔipdE2 mutants had similar phenotypes, showing impaired growth on cholesterol and accumulating 5-OH HIP in the culture supernatant. Bioinformatic analyses revealed that IpdE1 and IpdE2 share many of the features of the α- and β-subunits, respectively, of heterotetrameric ACADs that are encoded by adjacent genes in many steroid-degrading proteobacteria. When coproduced in a rhodococcal strain, IpdE1 and IpdE2 of Mtb formed a complex that catalyzed the dehydrogenation of 5OH-HIP coenzyme A (5OH-HIP-CoA) to 5OH-3aα-H-4α(3'-prop-1-enoate)-7aβ-methylhexa-hydro-1,5-indanedione coenzyme A ((E)-5OH-HIPE-CoA). This corresponds to the initial step in the pathway that leads to degradation of steroid C and D rings via β-oxidation. Small-angle X-ray scattering revealed that the IpdE1-IpdE2 complex was an α₂β₂ heterotetramer typical of other ACADs involved in steroid catabolism. These results provide insight into an important class of steroid catabolic enzymes and a potential virulence determinant in Mtb.

[Analysis on poor efficacy factors in the treatment of recurrent/refractory B-cell lymphoma with CD19 CAR-T cells]

Objective: To investigate the factors influencing the efficacy of CD19 chimeric antigen receptor T (CAR-T) cells in the treatment of patients with relapsed refractory B cell lymphoma and to provide evidence for further improvement of CAR-T efficacy. Methods: A total of 34 patients with relapsed and refractory B-cell lymphoma were recruited from the Department of Hematology of Tianjin First Central Hospital from February 2017 to January 2019. All patients received CD19 CAR-T cell therapy. These patients were evaluated for efficacy, factors with poor efficacyand adverse effects. Results: The overall response rate was 58.8% (20/34) and the complete remission rate was 41.2% (14/34) after infusion of CD19 CAR-T cells in 34 patients with relapsed refractory B cell lymphoma. According to the efficacy of CAR-T cells, patients were divided into two groups, 20 in the effective group and 14 in the poorly effective group. The median am ount of CD19 CAR-T cell infusions in these two groups were 8.6 (5.0-12.7)×10(6)/kg and 9.7 (5.8-15.0) × 10(6)/kg, respectively, and the difference was not statistically significant (P=0.654). The percentage of CD19 CAR-T cells in the effective group and the poorly treated group was 10.28% (3.92%-44.16%) and 4.05% (0.92%-28.63%), respectively.The effective group had a higher proportion of CAR-T cells than the poorly treated group, but the difference was not statistically significant (P=0.371).The presence of massive mass was an unfavorable factor affecting the efficacy of CD19 CAR-T cells and the difference was statistically significant (P=0.001). Logistic regression multivariate analysis showed that the characteristics of massive tumors were still independent prognostic factors for poor efficacy of CD19 CAR-T cells (P=0.005, OR=0.039). Of all 34 patients, there were 70.6% (24/34) who showed varying degrees of adverse reactions after the infusion of CD19 CAR-T cells, mainly cytokines release syndrome (CRS). The median time of occurrence of fever was on the third day after infusion (0-11th) day. 16 patients were with grade 1 CRS, 7 with grade 2, and 1 with grade 3. After glucocorticoids and support treatment, they all showed improvements. Conclusions: CD19 CAR-T cell therapy has achieved a certain effect in CD19(+)B cell lymphoma, but has poor efficacy on some patients. Large mass tumors may be an adverse factors to CAR-T cell treatment.

Time-Integrated Neutrino Source Searches with 10 Years of IceCube Data

This Letter presents the results from pointlike neutrino source searches using ten years of IceCube data collected between April 6, 2008 and July 10, 2018. We evaluate the significance of an astrophysical signal from a pointlike source looking for an excess of clustered neutrino events with energies typically above ∼1  TeV among the background of atmospheric muons and neutrinos. We perform a full-sky scan, a search within a selected source catalog, a catalog population study, and three stacked Galactic catalog searches. The most significant point in the northern hemisphere from scanning the sky is coincident with the Seyfert II galaxy NGC 1068, which was included in the source catalog search. The excess at the coordinates of NGC 1068 is inconsistent with background expectations at the level of 2.9σ after accounting for statistical trials from the entire catalog. The combination of this result along with excesses observed at the coordinates of three other sources, including TXS 0506+056, suggests that, collectively, correlations with sources in the northern catalog are inconsistent with background at 3.3σ significance. The southern catalog is consistent with background. These results, all based on searches for a cumulative neutrino signal integrated over the 10 years of available data, motivate further study of these and similar sources, including time-dependent analyses, multimessenger correlations, and the possibility of stronger evidence with coming upgrades to the detector.

Autologous oxygen release nano bionic scaffold composite miR-106a induced BMSCs enhances osteoblast conversion and promotes bone repair through regulating BMP-2

OBJECTIVE

Suitable seed cells and selection of bioactive scaffold materials are the main research contents of bone tissue engineering. It was showed that autologous oxygen release nano bionic scaffold could promote the osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs). The role of microRNA-106a (miR-106a) in regulating BMSCs differentiation has not been reported. We intend to investigate the role of autologous oxygen release nano bionic scaffold composite miR-106a in inducing BMSCs constructing tissue engineering bone.

MATERIALS AND METHODS

Rat BMSCs were isolated and transfected by using miR-106a scramble or miR-106a inhibitor. Healthy male Sprague-Dawly (SD) rats were randomly divided into three groups, including bone fracture group established as rat tibial fracture model, negative control group implanted by autologous oxygen release nano bionic scaffold composite miR-106a scramble BMSCs, and miR-106a inhibitor group implanted by autologous oxygen release nano bionic scaffold composite miR-106a inhibitor BMSCs. Callus growth was observed. Alkaline phosphatase (ALP) activity was detected. Bone morphogenetic protein 2 (BMP-2) expression was tested by Real-time PCR (RT-PCR) and Western blot assay. Collagen II production was determined by RT-PCR.

RESULTS

Autologous oxygen release nano bionic scaffold composite BMSCs significantly increased local bone mineral density, promoted callus healing, facilitated ALP secretion, elevated collagen II expression, and up-regulated BMP-2 mRNA and protein levels compared with fracture group (p<0.05). Autologous oxygen release nano bionic scaffold composite miR-106a induced BMSCs exhibited more significant effect on bone repair (p<0.05).

CONCLUSIONS

Autologous oxygen release nano bionic scaffold composite miR-106a induced BMSCs enhanced osteoblast conversion and promoted bone repair through regulating BMP-2.

Mycobacterium tuberculosis Exploits a Heterohexameric Enoyl-CoA Hydratase Retro-Aldolase Complex for Cholesterol Catabolism

Cholesterol catabolism plays an important role in Mycobacterium tuberculosis's (Mtb's) survival and persistence in the host. Mtb exploits three β-oxidation cycles to fully degrade the side chain of cholesterol. Five cistronic genes in a single operon encode three enzymes, 3-oxo-4-pregnene-20-carboxyl-CoA dehydrogenase (ChsE1-ChsE2), 3-oxo-4,17-pregnadiene-20-carboxyl-CoA hydratase (ChsH1-ChsH2), and 17-hydroxy-3-oxo-4-pregnene-20-carboxyl-CoA retro-aldolase (Ltp2), to perform the last β-oxidation cycle in this pathway. Among these three enzymes, ChsH1-ChsH2 and Ltp2 form a protein complex that is required for the catalysis of carbon-carbon bond cleavage. In this work, we report the structure of the full length ChsH1-ChsH2-Ltp2 complex based on small-angle X-ray scattering and single-particle electron microscopy data. Mutagenesis experiments confirm the requirement for Ltp2 to catalyze the retro-aldol reaction. The structure illustrates how acyl transfer between enzymes may occur. Each protomer of the ChsH1-ChsH2-Ltp2 complex contains three protein components: a chain of ChsH1, a chain of ChsH2, and a chain of Ltp2. Two protomers dimerize at the interface of Ltp2 to form a heterohexameric structure. This unique heterohexameric structure of the ChsH1-ChsH2-Ltp2 complex provides entry to further understand the mechanism of cholesterol catabolism in Mtb.

[Philadelphia chromosome-negative myeloid neoplasms in patients with Philadelphia chromosome-positive chronic myeloid leukemia during tyrosine kinase inhibtor-therapy]

Objective: To compare the clinical features between the 2 cohorts developing myelodysplastic syndrome or acute myeIogenous Ieukemia in Philadelphia chromosome-negative cells (Ph(-) MDS/AML) and maintaining disease stable in the patients with Philadelphia chromosome-positive chronic myeloid Ieukemia (Ph(+) CML) who had clonal chromosomal abnormalities in Philadelphia chromosome-negative metaphases (CCA/Ph(-)) during tyrosine kinase inhibtor (TKI) - therapy. Methods: We retrospectively analyzed Ph(+) CML patients who developed CCA/Ph(-) during TKI-therapy from May 2001 to December 2017. Results: Data of CCA/Ph(-) 63 patients, including 7 progressing to Ph(-) MDS/AML and 56 remaining disease stable were collected. Compared with those with stable disease, patients with Ph(-)MDS/AML had lower hemoglobin (P=0.007) and platelet (P=0.006) counts, and higher proportion of peripheral blasts (P<0.001) when the first time CCA/Ph(-) was detected, and more mosonomy 7 abnormality (5/7, 71.4%) when MDS or AML was diagnosed; meanwhile, trisomy 8 (32/56, 57.1%) was more common in those with stable disease. Outcome of the patients with Ph(-) MDS/AML were poor. However, most of those with CCA/Ph(-) and stable disease had optimal response on TKI-therapy. Conclusions: A few patients with Ph(+) CML developed CCA/Ph(-) during TKI-therapy, most of them had stable disease, but very few patients developed Ph(-) MDS/AML with more common occurrence of monosomy 7 or unknown cytopenia. Our data suggested the significance of monitoring of peripheral blood smear, bone marrow morphology and cytogenetic analysis once monosomy 7 or unknown cytopenia occurred.

Mce3R Stress-Resistance Pathway Is Vulnerable to Small-Molecule Targeting That Improves Tuberculosis Drug Activities

One-third of the world’s population carries Mycobacterium tuberculosis (Mtb), the infectious agent that causes tuberculosis (TB), and every 17 s someone dies of TB. After infection, Mtb can live dormant for decades in a granuloma structure arising from the host immune response, and cholesterol is important for this persistence of Mtb. Current treatments require long-duration drug regimens with many associated toxicities, which are compounded by the high doses required. We phenotypically screened 35 6-azasteroid analogues against Mtb and found that, at low micromolar concentrations, a subset of the analogues sensitized Mtb to multiple TB drugs. Two analogues were selected for further study to characterize the bactericidal activity of bedaquiline and isoniazid under normoxic and low-oxygen conditions. These two 6-azasteroids showed strong synergy with bedaquiline (fractional inhibitory concentration index = 0.21, bedaquiline minimal inhibitory concentration = 16 nM at 1 μM 6-azasteroid). The rate at which spontaneous resistance to one of the 6-azasteroids arose in the presence of bedaquiline was approximately 10^–9, and the 6-azasteroid-resistant mutants retained their isoniazid and bedaquiline sensitivity. Genes in the cholesterol-regulated Mce3R regulon were required for 6-azasteroid activity, whereas genes in the cholesterol catabolism pathway were not. Expression of a subset of Mce3R genes was down-regulated upon 6-azasteroid treatment. The Mce3R regulon is implicated in stress resistance and is absent in saprophytic mycobacteria. This regulon encodes a cholesterol-regulated stress-resistance pathway that we conclude is important for pathogenesis and contributes to drug tolerance, and this pathway is vulnerable to small-molecule targeting in live mycobacteria.

[A comparative study of induction chemotherapy with or without autologous hematopoietic stem cell transplantation in the treatment of newly diagnosed young medium/high risk diffuse large B cell lymphoma patients]

Objective: To compare the efficacy of induction chemotherapy with or without autologous hematopoietic stem cell transplantation (auto-HSCT) for newly diagnosed young diffuse large B cell lymphoma (DLBCL) patients. Methods: The retrospective study was performed in 90 cases of young patients (≤60 years) with newly diagnosed DLBCL and an age-adjusted International Prognostic Index (aa-IPI) score of 2 or 3. All of them were treated with R-CHOP (32 cases, rituximab combined with CHOP), dose-intensive regimens (DA-EPOCH, Hyper CVAD/MA or ESHAP) combined with or without rituximab (25 cases), and consolidated with up-front auto-HSCT (33 cases), respectively. The efficacy and the potential predictors were evaluated. Results: ①The median age of 90 patients was 43 (18-60) years old. The median follow-up time was 42 (3-110) months. ②The 5-year progression-free survival (PFS) for R-CHOP group, dose-intensive chemotherapy group and auto-HSCT group were (33.5±10.7) %, (55.3±10.1) % and (65.8±13.6) % (P=0.012), the 5-year overall survival (OS) were (49.7±9.0) %, (61.6±10.2) % and (78.6±7.8) % (P=0.035), respectively. There was no significant difference in 5-years PFS and OS between the R-CHOP group and dose-intensive chemotherapy group (P=0.519, P=0.437) compared with that of the dose-intensive chemotherapy group, auto-HSCT group has higher 5-year PFS (P=0.042). ③ When stratified with IPI score, the high-risk group treated with auto-HSCT (26 cases) showed similar 5-years PFS and 5-years OS to those in the low-risk group with chemotherapy alone (12 cases were in R-CHOP group and 8 cases were in dose-intensive chemotherapy group) [5-years PFS were (62.3 ±14.3)%, (58.3 ±18.6)% and (51.4±18.7)%, respectively, P=0.686; 5-years OS were (69.2±13.9)%, (62.5±15.5)% and (58.3±18.6)%, respectively, P=0.592]. ④However, the high-risk group treated with auto-HSCT (26 cases) showed superior 5-years PFS (P=0.002) and 5-years OS (P=0.019) compared to the high-risk group with chemotherapy alone (20 cases were in R-CHOP group and 17 cases were in dose-intensive chemotherapy group) [5-years PFS were (62.3±14.3)%, (41.1±13.5)% and (21.9±11.6)%, respectively; 5-years OS were (69.2±13.9)%, (51.5%±14.0)% and (35.4±13.6)%, respectively]. ⑤In the univariate analysis, as a whole, patients diagnosed with GCB subtype had higher 3-years PFS (P=0.022) and 3-years OS (P=0.037) compared to non-GCB subtype patients; in subgroup analysis, patients diagnosed with GCB subtype had higher 3-years PFS and 3-years OS compared to non-GCB subtype both in R-CHOP group (P=0.030, P=0.041) and dose-intensive chemotherapy group (P=0.044, P=0.047), but not in auto-HSCT group (P=0.199, P=0.093). ⑥In the multivariate analysis, different molecular classification (GCB/non-GCB) was an independent predictor for PFS and OS both in R-CHOP group [HR=0.274 (95% CI 0.094-0.800), P=0.018; HR=0.408 (95% CI 0.164-1.015), P=0.045] and dose-intensive chemotherapy group [HR=0.423 (95% CI 0.043-1.152), P=0.048; HR=5.758 (95% CI 0.882-6.592), P=0.035]. However, there was no significant difference in PFS and OS for auto-HSCT group between GCB/non-GCB patients. Conclusion: Induction chemotherapy followed by up-front auto-HSCT has significant effect on efficacy for young and untreated patients with high risk DLBCL. Combined with induction chemotherapy followed by up-front auto-HSCT could improve the prognosis of non-GCB patients.

[Ibrutinib inhibits mesenchymal stem cells-mediated drug resistance in diffuse large B-cell lymphoma]

目的

探讨依布替尼克服弥漫大B细胞淋巴瘤（DLBCL）细胞耐药的机制。

方法

①体外实验：以DLBCL细胞系SUDHL10细胞（GCB亚型）、HBL-1（ABC亚型）以及8例DLBCL患者原代细胞为研究对象，与正常人骨髓基质细胞（MSC）共培养后，显微镜下计数向MSC趋化迁移及与MSC黏附的DLBCL细胞数，ELISA法检测MSC的CXCL12表达水平，流式细胞术检测DLBCL细胞的CXCR4表达水平；以携带有CXCR4的慢病毒转染HBL-1细胞，米托蒽醌、依布替尼处理后与MSC共培养，流式细胞术检测细胞凋亡水平；倒置显微镜下观察HBL-1细胞集落形成情况。②体内实验：以HBL-1细胞构建的NOD/SCID肿瘤模型小鼠为研究对象，观察依布替尼治疗后肿瘤体积变化。

结果

①依布替尼处理后，DLBCL细胞向MSC的迁移数和与MSC的黏附比例明显降低（P值均<0.05），并呈剂量依赖性。②与依布替尼处理前比较，处理后MSC的CXCL12表达水平降低（SUDHL10细胞：660 pg/ml对1 400 pg/ml，P=0.004；HBL-1细胞：720 pg/ml对1 490 pg/ml，P=0.018；DLBCL原代细胞：850 pg/ml对1 450 pg/ml，P=0.004），DLBCL细胞的CXCR4表达水平降低（P值均<0.05）。③共培养时，对照组、米托蒽醌组、依布替尼组、米托蒽醌组+依布替尼组的HBL-1细胞凋亡比例分别为15.1%、17.5%、23.5%、58.7%，转染过表达CXCR4后，HBL-1细胞凋亡比例分别为14.2%、16.1%、22.5%、38.3%，共培养联合用药组HBL-1细胞凋亡比例高于单药培养组，差异均有统计学意义（P值均<0.05）。④对照组、MSC组、依布替尼组、MSC组+依布替尼组集落数分别为113±5、205±4、62±9、123±3（每孔2.5×10³），模型小鼠皮下肿瘤体积分别为6 500、17 000、4 000、10 000 mm³，依布替尼处理后较处理前集落数和肿瘤体积明显减少，差异均有统计学意义（P值均<0.05）。

结论

依布替尼靶向作用于CXCL12/CXCR4轴，抑制CXCR4表达从而克服MSC介导的耐药作用，并且能够在体内外抑制MSC促淋巴瘤细胞集落形成的作用。为依布替尼治疗复发耐药DLBCL提供了理论依据。

Constraints on Minute-Scale Transient Astrophysical Neutrino Sources

High-energy neutrino emission has been predicted for several short-lived astrophysical transients including gamma-ray bursts (GRBs), core-collapse supernovae with choked jets, and neutron star mergers. IceCube's optical and x-ray follow-up program searches for such transient sources by looking for two or more muon neutrino candidates in directional coincidence and arriving within 100 s. The measured rate of neutrino alerts is consistent with the expected rate of chance coincidences of atmospheric background events and no likely electromagnetic counterparts have been identified in Swift follow-up observations. Here, we calculate generic bounds on the neutrino flux of short-lived transient sources. Assuming an E^{-2.5} neutrino spectrum, we find that the neutrino flux of rare sources, like long gamma-ray bursts, is constrained to <5% of the detected astrophysical flux and the energy released in neutrinos (100 GeV to 10 PeV) by a median bright GRB-like source is <10^{52.5}  erg. For a harder E^{-2.13} neutrino spectrum up to 30% of the flux could be produced by GRBs and the allowed median source energy is <10^{52}  erg. A hypothetical population of transient sources has to be more common than 10^{-5}  Mpc^{-3}  yr^{-1} (5×10^{-8}  Mpc^{-3}  yr^{-1} for the E^{-2.13} spectrum) to account for the complete astrophysical neutrino flux.

[Vertigo and sensorineural hearing loss due to syphilis: differential diagnosis and treatment]

Objective:To analyze the etiology of repeatedly attacks of intractable vertigo and some types of sensorineural deafness whose clinical manifestation were not in conformity with the known spectrum diseases，and explore the screening method to prevent missed diagnosis or misdiagnosis, then provide references for clinical diagnosis and treatment for rare etiology. Method:The authors retrospectively analyzed the clinical manifestations, diagnosis, treatment and prognosis from 4 cases of vertigo sufferers and 2 cases of hearing impairment sufferers whose serological tests were positive for syphilis. All these 6 cases were treated with large doses of penicillin aqueous solutions (24 million U/d), multi-times intravenous infusion, the course of the treatment was 14 d. Result:The clinical manifestations of these 6 patients were lack of characteristic, as well as the results of hearing and vestibular function, imaging diagnosis. Positive syphilis detection of serology and cerebrospinal fluid tests were the main diagnostic basis. After anti-syphilis treatment, 5 cases got satisfied clinical symptoms improvement, 1 case suffered from low-tone sensorineural hearing loss, whose hearing fluctuated recurrently. Conclusion:Syphilis infection may damage the Ⅷ cranial nerve and then lead to vertigo and hearing loss, through chronic syphilitic osteitis of temporal bone, atrophy of organ of corti, osteolytic lesion surrounding the endolymphatic duct, and neurosyphilis. For patients presented with intractable vertigo, and those whose clinical manifestations are not in conformity with the known diseases of unilateral ear or bilateral ears rapidly progressive deafness, syphilis serology screening and validation tests are recommended in case of missed diagnosis or misdiagnosis.