First Dark Matter Search Results from the LUX-ZEPLIN (LZ) Experiment

The LUX-ZEPLIN experiment is a dark matter detector centered on a dual-phase xenon time projection chamber operating at the Sanford Underground Research Facility in Lead, South Dakota, USA. This Letter reports results from LUX-ZEPLIN's first search for weakly interacting massive particles (WIMPs) with an exposure of 60 live days using a fiducial mass of 5.5 t. A profile-likelihood ratio analysis shows the data to be consistent with a background-only hypothesis, setting new limits on spin-independent WIMP-nucleon, spin-dependent WIMP-neutron, and spin-dependent WIMP-proton cross sections for WIMP masses above 9  GeV/c^{2}. The most stringent limit is set for spin-independent scattering at 36  GeV/c^{2}, rejecting cross sections above 9.2×10^{-48}  cm at the 90% confidence level.

Neural Stem Cell-Derived Exosomes Improve Neurological Function in Rats with Cerebral Ischemia-Reperfusion Injury by Regulating Microglia-Mediated Inflammatory Response

Purpose

To investigate the effect of neural stem cell-derived exosomes (NSC-Exos) on neural function after rat cerebral ischemia-reperfusion injury by regulating microglia-mediated inflammatory response.

Methods

SD rats were randomly divided into Sham group, IRI group, PBS group and NSC-Exos group. Each group was divided into 1d, 3d, 7d and 14d subgroups. In the Sham group, only cervical vessels were isolated without blockage. MCAO model was constructed in the other three groups by blocking middle cerebral artery with thread embolism. PBS group and NSC-Exos group were, respectively, injected into the lateral ventricle of PBS and Exos. Neurobehavioral deficit scores were performed for each subgroup at relative time points, then brains were taken for TTC staining, parietal cortex histopathology and microglia-mediated inflammatory response-related factors were detected.

Results

Compared with Sham group, neurological defect score and infarction volume in both the IRI and PBS groups were significantly increased. The exploration target quadrant time and escape latency time of maze test were increased. The number of CD86⁺/Iba1⁺ double-positive cells increased, while CD206⁺/Iba1⁺ double-positive cells decreased. The expressions of IL-6 and CD86 in parietal cortex were increased, while the expressions of Arg1 and CD206 were decreased. Compared with the IRI group and PBS group, neurological defect score and infarction volume in NSC-Exos group were decreased. The exploration target quadrant time and escape latency time of water maze test were decreased. The number of CD206⁺/Iba1⁺ double-positive cells increased, while CD86⁺/Iba1⁺ double-positive cells decreased. The expressions of Arg1 and CD206 in parietal cortex were increased, while the expressions of IL-6 and CD86 were decreased.

Conclusion

NSC-Exos can promote the polarization of microglia, that is, inhibit the polarization of M1 and promote polarization of M2, reduce microglia-mediated neuroinflammation, suggesting that NSC-Exos may be a strategy for the treatment of microglia-mediated neuroinflammation after ischemic brain injury.

Association between chronic disease and depression among older adults in China: the moderating role of social participation

OBJECTIVES

Depression is an increasingly serious mental health problem worldwide. Therefore, this study aimed to explore the association between chronic disease and depression and to further test the moderating role of social participation in this association.

STUDY DESIGN

This is a cross-sectional study.

METHODS

We screened 6421 subjects from the 2018 wave of the China Health and Retirement Longitudinal Study database. Social participation and depressive symptoms were assessed using the 12-item self-made scale and 10-item Center for Epidemiological Studies Depression Scale, respectively. Hierarchical regression was used to determine the main effect of chronic disease and depression and the moderating effect of social participation on the relationship between chronic disease and depression.

RESULTS

In this study, 3172 (49.40%) eligible participants were male, 4680 (72.90%) older adults were concentrated in the 65-74 years group, and 68.20% reported good health status. In addition, gender, area, education level, marital status, health status, health insurance, health service utilization, and physical activity intensity were significant factors associated with participants' depression status (P < 0.05). The results also showed that a higher number of chronic diseases were associated with a higher depression score after adjusting for confounders (single disease: β = 0.074, P < 0.001; multimorbidity: β = 0.171, P < 0.001) and that social participation played a moderating role in this association (β = -0.030, P < 0.05).

CONCLUSIONS

This study tentatively suggests that a higher number of chronic diseases are associated with rising depression scores in the older Chinese population. In addition, the moderating effect of social participation suggests that more active social engagement should be promoted in this population to alleviate the depressive mood.

The recovery of aerosol-sized microplastics in highly refractory vegetal matrices for identification by automated Raman microspectroscopy

Ombrotrophic peatlands are fed uniquely by atmospheric inputs and therefore have much potential as temporal archives of atmospheric microplastic (MP) deposition, yet the recovery and detection of MP within an almost purely organic matrix is challenging. This study presents a novel peat digestion protocol using sodium hypochlorite (NaClO) as a reagent for biogenic matrix removal. NaClO is more efficient than hydrogen peroxide (H₂O₂). By using purged air-assisted digestion, NaClO (50 vol%) reached 99% matrix digestion compared with 28% and 75% by H₂O₂ (30 vol%) and Fenton's reagent, respectively. At a concentration of 50 vol% NaClO did however chemically disintegrate small amounts (<10 mass %) of polyethylene terephthalate (PET) and polyamide (PA) fragments in the millimeter size range. Observation of PA6 in natural peat samples, while not found in the procedural blanks, questions whether PA is fully disintegrated by NaClO. The protocol was applied to three commercial sphagnum moss test samples, in which MP particles in the range of 0.8-65.4 μm were detected by Raman microspectroscopy. The MP mass% was determined at 0.012% corresponding to 129 thousand MP particles/g, of which 62% were smaller than 5 μm and 80% were smaller than 10 μm, yet were accountable for only 0.4% (500 ng) and 3.2% (4 μg) of the total mass of MP, respectively. These findings underline the importance of the identification of particles Ø < 5 μm when investigating atmospheric MP deposition. The MP counts were corrected for MP recovery loss and procedural blank contamination. MP spike recovery following the full protocol was estimated at 60%. The protocol offers an efficient way of isolating and pre-concentrating most aerosol sized MPs in large quantities of refractory vegetal matrices and enables the automated μRaman scanning of thousands of particles at a spatial resolution on the order of 1 μm.

Severe Thrombocytopenia with Acute Cerebral Infarction: A Case Report and Literature Review

Common causes of thrombocytopenia include pseudo-thrombocytopenia, splenomegaly, decreased bone marrow production, and increased platelet destruction or depletion. The main clinical manifestation is bleeding, and thrombosis-related complications are rare. This article reports an 87-year-old woman with severe thrombocytopenia for more than 7 years. On day 6 in the hospital, the patient suddenly fell into a coma, and emergency head computed tomography (CT) displayed acute cerebral infarction of the left cerebellar hemisphere, brainstem, and left thalamus. Although thrombocytopenia is often associated with bleeding, there is still a need for vigilance against ischemic diseases. We analyzed the possible causes of acute cerebral infarction with thrombocytopenia and reviewed the literature. Our case is different from the causes of cerebral infarction reported in previous articles, so the relationship between thrombocytopenia and acute cerebral infarction needs further study. The patient, in this case, was not given anticoagulant or antiplatelet therapy but recovered well. It shows that individualized treatment is effective.

[Effects of the kynurenine pathway on the osteogenic differentiation of periodontal ligament stem cells]

Objective: To explore the effect of kynurenine pathway on the osteogenic differentiation of periodontal ligament stem cells (PDLSC). Methods: Unstimulated saliva samples were collected from 19 patients with periodontitis (periodontitis group) and 19 periodontally healthy individuals (health group) in Nanjing Stomatological Hospital, Affiliated Hospital of Medical School, Nanjing University from June to October of 2022. Contents of kynurenine and the metabolites in saliva samples were analyzed by ultra-performance liquid chromatography-tandem mass spectrometry. The expressions of indoleamine 2, 3-dioxygenase (IDO) and aryl hydrocarbon receptor (AhR) were further detected by immunohistochemistry in gingival tissues. The PDLSC used in this study were isolated from extracted teeth for orthodontic treatment in Nanjing Stomatological Hospital, Affiliated Hospital of Medical School, Nanjing University from July to November of 2022. Experiments were then conducted using the cells by incubating with (kynurenine group) or without kynurenine (control group) in vitro. Seven days later, alkaline phosphatase (ALP) staining and assays of ALP activity were performed. Real-time fluorescence quantitative PCR (RT-qPCR) was utilized to detect the expressions of osteogenic related genes ALP, osteocalcin (OCN), runt-related transcription factor 2 (RUNX2), collagen type-Ⅰ (COL-Ⅰ) as well as the kynurenine pathway-associated genes AhR, cytochrome P450 family (CYP) 1A1, CYP1B1. Western blotting was used to detect the expression levels of RUNX2, osteopontin (OPN) and AhR proteins on day 10 and alizarin red staining was performed to observe the formation of mineral nodules on day 21 in control group and kynurenine group. Results: Salivary concentrations of kynurenine [8.26 (0, 19.60) nmol/L] and kynurenic acid [11.4 (3.34, 13.52) nmol/L] were significantly higher in the periodontitis group than in the health group [0.75(0, 4.25) nmol/L, 1.92(1.34, 3.88) nmol/L] (Z=-2.84, P=0.004; Z=-3.61, P<0.001). The expression levels of IDO (18.33±2.22) and AhR (44.14±13.63) in gingival tissues of periodontitis patients were significantly higher than that of the health group (12.21±2.87, 15.39±5.14) (t=3.38, P=0.015; t=3.42, P=0.027). In vitro, the ALP activity of PDLSC in the kynurenine group (291.90±2.35) decreased significantly compared with the control group (329.30±19.29) (t=3.34, P=0.029). The mRNA expression levels of ALP, OCN and RUNX2 in the kynurenine group (0.43±0.12, 0.78±0.09, 0.66±0.10) were decreased compared with the control group (1.02±0.22, 1.00±0.11, 1.00±0.01) (t=4.71, P=0.003; t=3.23, P=0.018; t=6.73, P<0.001), while the levels of AhR and CYP1A1 were increased in the kynurenine group (1.43±0.07, 1.65±0.10) compared with those in the control group (1.01±0.12, 1.01±0.14) (t=5.23, P=0.006; t=6.59, P<0.001). No significant difference was observed in COL-Ⅰ and CYP1B1 mRNA levels between groups. The protein levels of OPN, RUNX2 (0.82±0.05, 0.87±0.03) were reduced and that of AhR (1.24±0.14) was increased in the kynurenine group compared with those in the control group (1.00±0.00, 1.00±0.00, 1.00±0.00) (t=6.79, P=0.003; t=7.95, P=0.001; t=3.04, P=0.039). Conclusions: Over-activated kynurenine pathway in periodontitis patients can promote upregulation of AhR and suppress the osteogenic differentiation of PDLSC.

[Primary cardiac angiosarcoma: a clinicopathological and molecular genetic analysis of thirteen cases]

Objective: To investigate the clinicopathological and molecular features of primary cardiac angiosarcoma (PCAS), and to analyze the correlation between KDR mutation and the clinicopathological features of PCAS. Methods: Thirteen cases of PCAS were collected at Beijing Anzhen Hospital, Capital Medical University from January 2007 to December 2021. The clinicopathological features, diagnosis, differential diagnosis and outcome were retrospectively analyzed. KDR mutation was detected by next-generation sequencing (NGS) and then the expression of KDR (VEGFR2) was determined by immunohistochemistry (IHC), with review of relevant literatures. Results: There were eight males and five females with a mean age of 45 years. The primary tumor was in the right atrium in 10 cases, left atrium in two cases and right ventricle in one case. The histomorphology was mainly poorly differentiated angiosarcoma (11 cases), with highly pleomorphic spindle or round cells in solid sheets, brisk mitotic activity and extensive necrosis. Vascular lumen formation was observed in two cases of high to moderate differentiation, and biphenotypic differentiation was seen in five cases. IHC staining showed CD34, CD31, Fli1, ERG and vimentin were diffusely positive, pan-cytokeratin was positive, Ki-67 index ranged from 3% to 90%, which was positively correlated with the differentiation degree and grade of the PCASs (P<0.05). At the end of follow-up period, one patient was alive, two patients were lost to follow-up, and the remaining 10 patients had an average survival time of 4.6 months. Finally, NGS sequencing was performed on seven samples after screening, and the results showed that KDR and NF1 mutations were both present in three cases. VEGFR2 expression had no significant correlation with the differentiation degree and grade of PCAS (P>0.05), and it was not related to KDR mutation. Conclusions: PCASs mainly occur in the right atrium, and are mainly poorly differentiated. Ki-67 index is helpful to assess the degree and grade of tumor differentiation. The occurrence and development of PCAS may be related to the pathway involved in KDR mutation, but KDR mutation has no clear correlation with clinicopathological characteristics of PCAS, and immunohistochemical staining can not replace gene detection to determine whether the tumor had KDR mutation.

[Clinical characteristics and placental pathology analysis of 14 cases of pregnancy with aortic dissection/aortic aneurysm]

Objective: To investigate the pathological changes of placenta in pregnant women with aortic dissection/aneurysm and their relationship with clinical features. Methods: The placental samples of 14 pregnant women with aortic dissection/aneurysm diagnosed from January 2012 to October 2021 and 10 normal placental samples of pregnant women from January 2021 to December 2021 at Beijing Anzhen Hospital Affiliated to Capital Medical University, Beijing, China were selected. Routine H&E staining and immunohistochemistry were used to analyze the histological features under light microscope. The clinical data were also analyzed. Results: The age of 14 pregnant patients with aortic dissection/aneurysm for placental examination ranged from 22 to 38 years (median, 28 years). The gestational ages ranged from 22 to 39 weeks (median, 34 weeks). The pregnancy of second trimester was noted in 2 cases, and the third trimester in 12 cases. All cases were singleton pregnancy. Seven cases were Stanford type A aortic dissection, 6 cases were Stanford type B aortic dissection, and one case was aortic root aneurysm. Four of the pregnant women underwent aortic dissection surgery after caesarean section, three underwent caesarean section after aortic dissection surgery, and seven underwent both caesarean section and aortic dissection procedures. Among the newborns, 2 cases were full-term birth, and 12 cases were premature birth. Twelve cases had alive newborns, and 2 cases stillbirths. Fetal/placental weight ratio (FPR)<10th percentile was in 5 cases and FPR>90th percentile in one case. Compared with the normal group, accelerated villus maturation and distal villus dysplasia were more frequently found in pregnancy with aortic dissection group (P<0.05). There was no significant difference in villi infarction and decidua vascular lesions between the two groups (P>0.05), nor was there correlation between the type of aortic dissection and distal villus dysplasia and accelerated villus maturation of placentas (P>0.05). The number of villous interstitial blood vessels in the placentas of pregnancy with aortic dissection group was significantly fewer than that in the normal control group (P<0.01). Conclusions: There are considerable pathological changes in the placentas of pregnant women with aortic dissection/aneurysm. The main histological features are accelerated villus maturation and distal villus dysplasia, which are manifestations of villous ischemia and hypoxia, and also a part of the placental pathological manifestations of maternal vascular dysperfusion.

Bioconjugation of COL1 protein on liquid-like solid surfaces to study tumor invasion dynamics

Tumor invasion is likely driven by the product of intrinsic and extrinsic stresses, reduced intercellular adhesion, and reciprocal interactions between the cancer cells and the extracellular matrix (ECM). The ECM is a dynamic material system that is continuously evolving with the tumor microenvironment. Although it is widely reported that cancer cells degrade the ECM to create paths for migration using membrane-bound and soluble enzymes, other nonenzymatic mechanisms of invasion are less studied and not clearly understood. To explore tumor invasion that is independent of enzymatic degradation, we have created an open three-dimensional (3D) microchannel network using a novel bioconjugated liquid-like solid (LLS) medium to mimic both the tortuosity and the permeability of a loose capillary-like network. The LLS is made from an ensemble of soft granular microgels, which provides an accessible platform to investigate the 3D invasion of glioblastoma (GBM) tumor spheroids using in situ scanning confocal microscopy. The surface conjugation of the LLS microgels with type 1 collagen (COL1-LLS) enables cell adhesion and migration. In this model, invasive fronts of the GBM microtumor protruded into the proximal interstitial space and may have locally reorganized the surrounding COL1-LLS. Characterization of the invasive paths revealed a super-diffusive behavior of these fronts. Numerical simulations suggest that the interstitial space guided tumor invasion by restricting available paths, and this physical restriction is responsible for the super-diffusive behavior. This study also presents evidence that cancer cells utilize anchorage-dependent migration to explore their surroundings, and geometrical cues guide 3D tumor invasion along the accessible paths independent of proteolytic ability.

A124 PERORAL ENDOSCOPIC MYOTOMY IS THE PREFERRED TREATMENT FOR PATIENTS WITH SYMPTOMATIC ZENKER’S DIVERTICULUM

Background

Zenker’s diverticulum (ZD) is a mucosal herniation at the pharyngoesophageal junction presenting with dysphagia, regurgitation and aspiration. While open surgical myotomy (OSM) is the conventional treatment option, select patients can undergo myotomy using endoscopic techniques.

Purpose

Evidence on third-space flexible endoscopy with myotomy is lacking, especially in North America. We aimed to assess the safety and efficacy of peroral endoscopic myotomy (POEM) for symptomatic ZD.

Method

Retrospective cohort study was performed of consecutive patients undergoing OSM and POEM completed in a tertiary hospital from 2010-2020. Only patients with accessible electronic medical records and at least 3 months of follow-up were included in this study. Data collected included: demographics, comorbidities, ZD characteristics, clinical and patient-reported outcomes.

Result(s)

14 patients underwent OSM and 18 patients underwent POEM. 10 of the patients undergoing POEM were considered for but were not able to get stapled endoscopic myotomy, the most common reasons were related to the technical limitations (ZD size too small, unable to hyper-extend neck, unable to position suspension laryngoscope). There were no significant differences between groups in age (p=0.35), BMI (p=0.38), Charlson comorbidity index (p=0.26) and size of ZD (p=0.92). Length of stay was significantly lower for POEM (0.4 vs. 3.1, p<0.01). Complications were more common and severe with OSM (36%, n=5) versus POEM (11%, n=2). The only complications post-POEM were contained esophageal perforations. Complications post-OSM included esophageal perforations requiring open cervical drainage, surgical site infections, recurrent laryngeal nerve injury/paresis, esophageal strictures requiring multiple dilatations. All patients undergoing POEM had 100% technical success with post-treatment barium esophagogram showing 100% resolution of obstruction/hang-up. The median follow-up time post-POEM was 11 months. Over the follow-up period there was a significant improvement of patient-reported outcomes, with a mean decrease of Eckardt score (4.7 to 1.1, p<0.001) and mean increase of Dakkak-Watson score (20.7 to 41, p<0.001). Only one patient had persistent ongoing symptoms of dysphagia post-POEM and was subsequently diagnosed with ineffective esophageal motility on high resolution manometry.

Conclusion(s)

POEM is a minimally invasive treatment option for ZD with high treatment success as well as reduced length of stay and complications. It is less invasive than OSM, more versatile than stapled endoscopic myotomy and is less prone to technical limitations.

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Disclosure of Interest

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Alpha-ketoglutarate up-regulates autophagic activity in peri-implant environment and enhances dental implant osseointegration in osteoporotic mice

AIM

The osseointegration of dental implants is impaired in patients with osteoporosis, leading to significantly higher failure rates. This study set out to investigate the potential effects of alpha-ketoglutarate (α-KG) on implant osseointegration in an osteoporotic mouse model.

MATERIALS AND METHODS

Female C57BL/6 mice received ovariectomy and bilateral first maxillary molar extraction at the age of 7 weeks. Dental implants were inserted 8 weeks after tooth extraction. In one of the groups, α-KG was administered via drinking water throughout the experimental period. Specimens were collected on post-implant days (PIDs) 3, 7, 14, and 21 for micro-CT, histological, and immunohistochemical analyses. At the same time, bone-marrow-derived mesenchymal stem cells (BMMSCs) treated with α-KG were interrogated for osteogenic differentiation, autophagic activity, and apoptosis.

RESULTS

α-KG supplementation in drinking water resulted in enhanced dental implant osseointegration in ovariectomized mice, with up-regulated osteogenic and autophagic activity and down-regulated osteoclast differentiation and cell apoptosis. α-KG-treated BMMSCs showed enhanced activity in proliferation, survival, colony formation, and osteogenic differentiation, as well as autophagic activity.

CONCLUSIONS

Systemic α-KG supplementation effectively prevents the failure of dental implant osseointegration in mice under an osteoporotic state.

Andrographolide Liquisolid using Porous-Starch as the Adsorbent with Enhanced Oral Bioavailability in Rats

Andrographolide (AGL) is the major component of Andrographispaniculata. The poor water solubility and low dissolution strongly affect its oral absorption. Liquisolid technology has been used to improve its dissolution and oral bioavailability. Liquisolid powders of AGL (AGL-LS-PSG) were obtained by firstly dissolving AGL in the mixture of NMP, PEG 6000 and Soluplus®, and solidified by absorption of the blend in porous starch. Angle of repose, Carr index and Hauser ratio presented good powder fluidity and compressibility characteristics of AGL-LS-PSG. The results of optical microscopic observation, PXRD and DSC analysis indicated that AGL has been completely adsorbed in porous starch granules and existed in an amorphous or molecularly dispersing state. AGL-LS-PSG can obviously increase the drug dissolution rate compared to commercial guttate pills and raw drug. In vivo pharmacokinetic behavior of AGL-LS-PSG was investigated following a single oral administration to rats. The C_max (0.37 ± 0.06 μg mL^-1) and AUC_0-2h (13.55 ± 2.67 μg h mL^-1) of AGL-LS-PSG were evidently increased compared to commercial guttate pills (C_max = 0.30 ± 0.21 μg mL^-1, AUC_0-2h = 9.88 ± 3.57 μg h mL^-1). This study indicated great potential of liquisolid technology in effectively improving the dissolution and bioavailability of AGL.

Enhanced Intrinsic Anomalous Valley Hall Effect Induced by Spin-Orbit Coupling in MXene Monolayer M3N2O2 (M = Y, La)

The limitation of suitable anomalous valley Hall effect (AVHE) materials has seriously hindered the booming development and the widespread application of valleytronics. Here, through the first-principles calculations, we propose a MXene monolayer Y₃N₂O₂ with spontaneous valley polarization (VP) of 21.3 meV, which induces intrinsic AVHE. The VP can be modulated linearly, which provides a route of effective control of the valley signals. Importantly, VP can be enhanced by adjusting up the spin-orbit coupling (SOC) based on a SOC Hamiltonian model and the first-principles calculations. From this physics underlying, we substitute the Y atom with the La atom and further propose the monolayer La₃N₂O₂, in which the heavy atom La will provide stronger SOC than Y atom. The spontaneous VP in La₃N₂O₂ is enhanced to 100.4 meV, so AVHE can be easily achieved. Our work not only provides compelling candidates for AVHE materials but also offers a novel mindset for finding suitable valleytronic devices.

20-MHz phased array ultrasound transducer for in vivo ultrasound imaging of small animals

In vivo ultrasound imaging with phased array transducers is of great importance for both clinical application and biomedical research. In this work, relaxor ferroelectric PMN-0.28PT single crystal with very high piezoelectric constant d₃₃ ≥ 2000 pC/N and electromechanical coupling coefficient k₃₃ ∼ 0.92 is used to fabricate high-frequency phased array transducers. A 128-element 20-MHz phased array transducer is successfully fabricated, and the optimized performance of -6 dB average bandwidth of ∼ 84 % and insertion loss of -43 dB are achieved. The axial and lateral imaging resolutions of the transducer are determined to be 81 µm and 243 µm, respectively. With Verasonics image platform, in vivo fisheye images are acquired, demonstrating the potential application of our developed high-frequency phased array transducer for biomedical research on small animals.

New Direct Limit on Neutrinoless Double Beta Decay Half-Life of ^{128}Te with CUORE

The Cryogenic Underground Observatory for Rare Events (CUORE) at Laboratori Nazionali del Gran Sasso of INFN in Italy is an experiment searching for neutrinoless double beta (0νββ) decay. Its main goal is to investigate this decay in ^{130}Te, but its ton-scale mass and low background make CUORE sensitive to other rare processes as well. In this Letter, we present our first results on the search for 0νββ decay of ^{128}Te, the Te isotope with the second highest natural isotopic abundance. We find no evidence for this decay, and using a Bayesian analysis we set a lower limit on the ^{128}Te 0νββ decay half-life of T_{1/2}>3.6×10^{24}  yr (90% CI). This represents the most stringent limit on the half-life of this isotope, improving by over a factor of 30 the previous direct search results, and exceeding those from geochemical experiments for the first time.

[Mid-term efficacy of China Net Childhood Lymphoma-mature B-cell lymphoma 2017 regimen in the treatment of pediatric Burkitt lymphoma]

Objective: To analyze the clinical characteristics of children with Burkitt lymphoma (BL) and to summarize the mid-term efficacy of China Net Childhood Lymphoma-mature B-cell lymphoma 2017 (CNCL-B-NHL-2017) regimen. Methods: Clinical features of 436 BL patients who were ≤18 years old and treated with the CNCL-B-NHL-2017 regimen from May 2017 to April 2021 were analyzed retrospectively. Clinical characteristics of patients at disease onset were analyzed and the therapeutic effects of patients with different clinical stages and risk groups were compared. Survival analysis was performed by Kaplan-Meier method, and Cox regression was used to identify the prognostic factors. Results: Among 436 patients, there were 368 (84.4%) males and 68 (15.6%) females, the age of disease onset was 6.0 (4.0, 9.0) years old. According to the St. Jude staging system, there were 4 patients (0.9%) with stage Ⅰ, 30 patients (6.9%) with stage Ⅱ, 217 patients (49.8%) with stage Ⅲ, and 185 patients (42.4%) with stage Ⅳ. All patients were stratified into following risk groups: group A (n=1, 0.2%), group B1 (n=46, 10.6%), group B2 (n=19, 4.4%), group C1 (n=285, 65.4%), group C2 (n=85, 19.5%). Sixty-three patients (14.4%) were treated with chemotherapy only and 373 patients (85.6%) were treated with chemotherapy combined with rituximab. Twenty-one patients (4.8%) suffered from progressive disease, 3 patients (0.7%) relapsed, and 13 patients (3.0%) died of treatment-related complications. The follow-up time of all patients was 24.0 (13.0, 35.0) months, the 2-year event free survival (EFS) rate of all patients was (90.9±1.4) %. The 2-year EFS rates of group A, B1, B2, C1 and C2 were 100.0%, 100.0%, (94.7±5.1) %, (90.7±1.7) % and (85.9±4.0) %, respectively. The 2-year EFS rates was higher in group A, B1, and B2 than those in group C1 (χ²=4.16, P=0.041) and group C2 (χ²=7.21, P=0.007). The 2-year EFS rates of the patients treated with chemotherapy alone and those treated with chemotherapy combined with rituximab were (79.3±5.1)% and (92.9±1.4)% (χ²=14.23, P<0.001) respectively. Multivariate analysis showed that stage Ⅳ (including leukemia stage), serum lactate dehydrogenase (LDH)>4-fold normal value, and with residual tumor in the mid-term evaluation were risk factors for poor prognosis (HR=1.38,1.23,8.52,95%CI 1.05-1.82,1.05-1.43,3.96-18.30). Conclusions: The CNCL-B-NHL-2017 regimen show significant effect in the treatment of pediatric BL. The combination of rituximab improve the efficacy further.