[Clinical features and follow-up study on 55 patients with adolescence-onset methylmalonic acidemia]

Objective: To investigate the clinical features and outcomes of adolescence-onset methylmalonic acidemia (MMA) and explore preventive strategies. Methods: This was a retrospective case analysis of the phenotypes, genotypes and prognoses of adolescence-onset MMA patients. There were 55 patients diagnosed in Peking University First Hospital from January 2002 to June 2023, the data of symptoms, signs, laboratory results, gene variations, and outcomes was collected. The follow-ups were done through WeChat, telephone, or clinic visits every 3 to 6 months. Results: Among the 55 patients, 31 were males and 24 were females. The median age of onset was 12 years old (range 10-18 yearsold). They visited clinics at Tanner stages 2 to 5 with typical secondary sexual characteristics. Nine cases (16%) were trigged by infection and 5 cases (9%) were triggered by insidious exercises. The period from onset to diagnosis was between 2 months and 6 years. Forty-five cases (82%) had neuropsychiatric symptoms as the main symptoms, followed by cardiovascular symptoms in 12 cases (22%), kidney damage in 7 cases (13%), and eye disease in 12 cases (22%). Fifty-four cases (98%) had the biochemical characteristics of methylmalonic acidemia combined with homocysteinemia, and 1 case (2%) had the isolated methylmalonic acidemia. Genetic diagnosis was obtained in 54 cases, with 20 variants identified in MMACHC gene and 2 in MMUT gene. In 53 children with MMACHC gene mutation,1 case had dual gene variants of PRDX1 and MMACHC, with 105 alleles. The top 5 frequent variants in MMACHC were c.482G>A in 39 alleles (37%), c.609G>A in 17 alleles (16%), c.658_660delAAG in 11 alleles (10%), c.80A>G in 10 alleles (10%), c.567dupT and c.394C>T both are 4 alleles (4%). All patients recovered using cobalamin, L-carnitine, betaine, and symptomatic therapy, and 54 patients (98%) returned to school or work. Conclusions: Patients with adolescence-onset MMA may triggered by fatigue or infection. The diagnosis is often delayed due to non-specific symptoms. Metabolic and genetic tests are crucial for a definite diagnosis. Treatment with cobalamin, L-carnitine, and betaine can effectively reverse the prognosis of MMA in adolescence-onset patients.

Improvement of coronary stent visualization using ultra-high-resolution photon-counting detector CT

OBJECTIVES

This study aimed to compare the image quality and diagnostic performance of standard-resolution (SR) and ultra-high-resolution (UHR) coronary CT angiography (CCTA) based on photon-counting detector CT (PCD-CT) of coronary stents and explore the best reconstruction kernel for stent imaging.

METHODS

From July 2023 to September 2023, patients were enrolled to undergo CCTA using a dual-source PCD-CT system after coronary angioplasty with stent placement. SR images with a slice thickness/increment of 0.6/0.4 mm were reconstructed using a vascular kernel (Bv48), while UHR images with a slice thickness/increment of 0.2/0.2 mm were reconstructed using vascular kernels of six sharpness levels (Bv48, Bv56, Bv60, Bv64, Bv72, and Bv76). The in-stent lumen diameters were evaluated. Subjective image quality was also evaluated by a 5-point Likert scale. Invasive coronary angiography was conducted in 12 patients (25 stents).

RESULTS

Sixty-nine patients (68.0 [61.0, 73.0] years, 46 males) with 131 stents were included. All UHR images had significantly larger in-stent lumen diameter than SR images (p < 0.001). Specifically, UHR-Bv72 and UHR-Bv76 for in-stent lumen diameter (2.17 [1.93, 2.63] mm versus 2.20 [1.93, 2.59] mm) ranked the two best kernels. The subjective analysis demonstrated that UHR-Bv72 images had the most pronounced effect on reducing blooming artifacts, showcasing in-stent lumen and stent demonstration, and diagnostic confidence (p < 0.001). Furthermore, SR and UHR-Bv72 images showed a diagnostic accuracy of 78.3% (95% confidence interval [CI]: 56.3%-92.5%) and 88.0% (95%CI: 68.8%-97.5%), respectively.

CONCLUSION

UHR CCTA by PCD-CT leads to significantly improved visualization and diagnostic performance of coronary stents, and Bv72 is the optimal reconstruction kernel showing the stent struts and in-stent lumen.

CLINICAL RELEVANCE STATEMENT

The significantly improved visualization of coronary stents using ultra-high resolution CCTA could increase the diagnostic accuracy for in-stent restenosis and avoid unnecessary invasive quantitative coronary angiography, thus changing the clinical management for patients after percutaneous coronary intervention.

KEY POINTS

Coronary stent imaging is challenging with energy-integrating detector CT due to "blooming artifacts." UHR images using a PCD-CT enhanced coronary stent visualization. UHR coronary stent imaging demonstrated improved diagnostic accuracy in clinical settings.

[Semiparametric analysis of nonparametric proportional hazards models with mixed dependent censored data]

OBJECTIVE

To construct a nonparametric proportional hazards (PH) model for mixed informative interval-censored failure time data for predicting the risks in heart transplantation surgeries.

METHODS

Based on the complexity of mixed informative interval-censored failure time data, we considered the interdependent relationship between failure time process and observation time process, constructed a nonparametric proportional hazards (PH) model to describe the nonlinear relationship between the risk factors and heart transplant surgery risks and proposed a two-step sieve estimation maximum likelihood algorithm. An estimation equation was established to estimate frailty variables using the observation process model. Ⅰ-spline and B-spline were used to approximate the unknown baseline hazard function and nonparametric function, respectively, to obtain the working likelihood function in the sieve space. The partial derivative of the model parameters was used to obtain the scoring equation. The maximum likelihood estimation of the parameters was obtained by solving the scoring equation, and a function curve of the impact of risk factors on the risk of heart transplantation surgery was drawn.

RESULTS

Simulation experiment suggested that the estimated values obtained by the proposed method were consistent and asymptotically effective under various settings with good fitting effects. Analysis of heart transplant surgery data showed that the donor's age had a positive linear relationship with the surgical risk. The impact of the recipient's age at disease onset increased at first and then stabilized, but increased against at an older age. The donor-recipient age difference had a positive linear relationship with the surgical risk of heart transplantation.

CONCLUSION

The nonparametric PH model established in this study can be used for predicting the risks in heart transplantation surgery and exploring the functional relationship between the surgery risks and the risk factors.

Impacts of Adaptive Statistical Iterative Reconstruction-V and Deep Learning Image Reconstruction Algorithms on Robustness of CT Radiomics Features: Opportunity for Minimizing Radiomics Variability Among Scans of Different Dose Levels

This study aims to investigate the influence of adaptive statistical iterative reconstruction-V (ASIR-V) and deep learning image reconstruction (DLIR) on CT radiomics feature robustness. A standardized phantom was scanned under single-energy CT (SECT) and dual-energy CT (DECT) modes at standard and low (20 and 10 mGy) dose levels. Images of SECT 120 kVp and corresponding DECT 120 kVp-like virtual monochromatic images were generated with filtered back-projection (FBP), ASIR-V at 40% (AV-40) and 100% (AV-100) blending levels, and DLIR algorithm at low (DLIR-L), medium (DLIR-M), and high (DLIR-H) strength levels. Ninety-four features were extracted via Pyradiomics. Reproducibility of features was calculated between standard and low dose levels, between reconstruction algorithms in reference to FBP images, and within scan mode, using intraclass correlation coefficient (ICC) and concordance correlation coefficient (CCC). The average percentage of features with ICC > 0.90 and CCC > 0.90 between the two dose levels was 21.28% and 20.75% in AV-40 images, and 39.90% and 35.11% in AV-100 images, respectively, and increased from 15.43 to 45.22% and from 15.43 to 44.15% with an increasing strength level of DLIR. The average percentage of features with ICC > 0.90 and CCC > 0.90 in reference to FBP images was 26.07% and 25.80% in AV-40 images, and 18.88% and 18.62% in AV-100 images, respectively, and decreased from 27.93 to 17.82% and from 27.66 to 17.29% with an increasing strength level of DLIR. DLIR and ASIR-V algorithms showed low reproducibility in reference to FBP images, while the high-strength DLIR algorithm provides an opportunity for minimizing radiomics variability due to dose reduction.

China Alzheimer's Disease and Neurodegenerative Disorder Research (CANDOR) -A Prospective Cohort Study for Alzheimer's Disease and Vascular Cognitive Impairment

BACKGROUND

Alzheimer's disease (AD) and vascular cognitive impairment (VCI) are the two main causes of dementia. AD and VCI share similar symptoms of cognitive decline and may be attributable to similar risk factors. Establishing a prospective cohort to compare VCI and AD would help to understand vascular risk factors related to dementia.

OBJECTIVES

China Alzheimer's disease and Neurodegenerative Disorder Research (CANDOR) study is a prospective multicenter cohort study. It aims to study the similarities and differences between AD and post stroke cognitive impairment (PSCI) in neuroimaging changes, disease progression, and multiple omics studies.

DESIGN

This is an ongoing study. From July 31, 2019, to August 1, 2022, we recruited 1449 participants with ages between 40 and 100 years. The cohort included three groups: AD group, PSCI group, and normal cognitive (NC) group. Data were collected in face-to-face interviews at baseline, and will be followed up every year for 4 years. The PSCI group had additional follow-ups at 3-month and 6-month after enrollment. Brain Magnetic Resonance Imaging (MRI) included high-resolution sequences for intracranial arteries. Cognitive assessments and follow-up information will be prospectively collected. Biological specimens including blood and urine at baseline were collected and tested.

PARTICIPANTS

The targeted sample size of PSCI group was 500, AD group with 600 and NC group with 2000. There were 1449 participants enrolled. Include 508 participants were in NC group, 387 in AD group and 554 in PSCI group.

MEASUREMENTS

Demographics, clinical parameters, and medical examinations were collected and performed. Cognitive assessment was performed to assess all cognitive domains including memory, language, executive function, and orientation function.

CONCLUSIONS

The CANDOR study is a prospective cohort study. Data from this cohort provide us an opportunity to investigate the contribution of vascular factors to dementia pathogenesis.

[Clonal hematopoiesis and its evolution of myeloproliferative neoplasms]

The mutations of myeloproliferative neoplasma (MPN) mainly include driver mutations and non-driver mutations. The driver mutations mainly include JAK2 mutations, CALR mutations and MPL mutations and non-driver mutations mainly include ASXL1, DNMT3A, TET2, SF3B1, EZH2, TP53, SRSF2, USAF1, etc. Driver and non-driver mutations and their clonal evolution affect the thrombosis and disease transformation of MPN. Clonal hematopoiesis of MPN can occur decades before diagnosis, even in the fetal stage. After the emergence of clonal hematopoiesis, until the emergence and progression of MPN, gene mutation order, inflammation, interferon therapy affect the disease phenotype and clonal hematopoiesis of MPN. Although great progress has been made in the understanding of MPN clonal hematopoiesis and its evolution with the development of next-generation sequencing, there are still many limitations. In this study, we mainly discuss gene mutations of MPN and their influences on the thrombosis, leukemia and fibrosis transformation, and the influencing factors of clonal evolution, aiming to summarize the influence of clonal hematopoiesis and its evolution on the complications, prognosis and survival of MPN.

The Feasibility of Level Ib Sparing Intensity Modulated Radiation Therapy in Nasopharyngeal Carcinoma Patients with High-Risk Factors: Based on International Guideline

PURPOSE/OBJECTIVE(S)

In spite of the rarity of level Ib recurrence after intensity-modulated radiation therapy, the International Guideline (IG) provides the risk factors for prophylactic coverage. In practice, however, there are significant differences between institutions. The purpose of this study is to examine the feasibility of sparing level Ib IMRT in NPC patients with high-risk factors based on IG.

MATERIALS/METHODS

From January 2014 to October 2017, newly-diagnostic, non-metastatic NPC patients in our center were retrospectively reviewed. According to the risk factors of prophylactic level Ib coverage in patients with negative level Ib recommended by IG, the characteristics of pre-treatment MRI were analyzed. Four high-risk factors were identified: a. involvement of the structures that drain to level Ib as first echelon (FES), including anterior half of nasal cavity, oral cavity, b. involvement of submandibular gland (SMG), c. with radiologic extranodal extension (rENE) in level II LNs, or d. maximal axial diameter (MAD)≧2 cm in level II LNs. Patients with risk factors were divided into Cohort A (with risk factors a), Cohort B (with risk factor b, but without a), and Cohort C (only with risk factors c and/or d). Recurrence rates of level Ib and regional relapse-free survival (RRFS) rates were evaluated in different cohorts.

RESULTS

A total of 961 patients were finally included. Thirty-six cases (3.7%) presented with radiologically positive level Ib metastasis. For the other patients with negative Ib LNs, there were 18, 65, 421, and 444 cases classified as FES involvement, SMG involvement, level II LNs with rENE, and level II nodal with MAD ≧2 cm. Excluding overlap, a total of 571 patients with risk factors were divided into three groups: Cohort A (n = 18), Cohort B (n = 49) and Cohort C (n = 504). Nine patients (9/961, 0.94%) developed level Ib recurrence. Except for 1 patient with positive Ib LNs at diagnosis, 2 did not meet any of the risk factors, while the other six (6/9, 66.7%) met at least one risk factor. The rate of recurrence at neck level Ib was highest in Cohort A (11.1%, 2/18; Ib-sparing group: 0/10, 0.0% vs Ib-covering group: 2/8, 25.0%; P = 0.183). In Cohort B, no cases were found with level Ib recurrence (0.0%, 0/49). In Cohort C, the rates were rare (0.8%, 4/504) in both groups (0.7%, 2/276 vs 0.9%, 2/228; P > 0.999). Among the three Cohorts, there were no significant differences in 5-year RRFS between two groups, which were 90.0% vs 62.5% (p = 0.248), 90.9% vs 92.0% (p = 0.905), and 92.6% vs 90.1% (p = 0.445), respectively. Among patients with high-risk factors, the incidence of grade 3-4 late dry mouth symptom was higher in the level Ib-covering group (3.1% vs 7.5%, P = 0.033).

CONCLUSION

Level Ib sparing appears safe and feasible for NPC patients with negative level Ib LNs, even if combined with risk factors: SMG involvement, and/or level II with rENE, and/or level II MAD ≧2 cm. Level Ib-sparing irradiation reduces dry mouth symptoms compared with level Ib-irradiation.

Unique T-cell Sub-Population Shifts after SBPT and Nivolumab in Platinum Refractory HNC: Biomarker Correlates from ROR1771

PURPOSE/OBJECTIVE(S)

ROR1771 was a clinical trial investigating the use of stereotactic body proton radiotherapy (SBPT) and nivolumab in recurrent platinum refractory head and neck squamous cell carcinoma (HNSCC). The planned analysis of T-cell subpopulation and biomarker response is herein presented.

MATERIALS/METHODS

Patients with metastatic histologically confirmed HNSCC from any primary site received 2 cycles of nivolumab followed by SBPT to 1-2 selected target lesion(s) (hilar/lung: 8 of 12 patients), followed by maintenance nivolumab. Peripheral blood mononuclear cells were isolated pre-/post-treatment. Flow cytometry identified T-cell subpopulations. Single Cell 5' Gene Expression (GEX) and V(D)J T Cell Receptor libraries were prepared using Single Cell Immune Profiling. Seurat (v4.1.1) was used to identify cell type clusters, and differential expression post-filtration was evaluated using the Wilcoxon Rank Sum test.

RESULTS

A total of 12 patients were eligible for analysis, with one alive at time of analysis, 52 months from start of treatment. Median overall survival here was 12.5 months vs. 7.5-months on CheckMate 141. SBPT ranged from 35-50 Gy. Sequential changes in T-cell populations from baseline were noted with initiation of nivolumab, driving decrease in tumor-reactive (TTR; CD11ahighPD1+CD8+), central memory (TCM; CCR7+CD45RA-), and effector T-cells (TEF; CCR7-CD45RA-). TTR and TCM increased following SBPT, with greatest increase (3.5x TTR and 5.2x TCM) in the surviving patient. An average of 68 genes with significant differential expression between timepoints (p<0.0001) demonstrated RNA gene expression changes across all cell subtypes, including ribosomal (RPL and RPS) genes, ACTB, FTL, MALAT1, and others. This averaged 113 genes across all timepoints in the surviving patient, with peak following nivolumab induction. On T-cell receptor (TCR) analysis of this patient, the predominant clonotype diversity changed substantially following nivolumab. Following SBPT, clonotype diversity again changed to include a milieu seen neither at baseline nor with nivolumab alone. These TCRs persisted for approximately 2 weeks following SBPT before returning to resemble the nivolumab-induced TCR diversity alone, coinciding with disease recurrence.

CONCLUSION

ROR1771 demonstrated overall survival favorably comparable to CheckMate 141. Biomarker analysis of peripheral blood samples demonstrated significant shifts in T-cell subpopulations and underlying gene expression to nivolumab and then to SBPT administration. SBPT to a target lesion changed TCR clonotypes within the peripheral blood beyond those seen with nivolumab administration, with fading of these TCR clonotypes coinciding with recurrence. SBPT in combination with nivolumab may drive systemic immunologic change above that induced by nivolumab alone and warrants further investigation.

[Association between volatile organic compounds and mortality risk of stroke]

Objective: To investigate the effect of volatile organic compounds (VOCs) exposure in the atmosphere on the risk of daily death from stroke in Guangzhou. Methods: Daily average concentrations of twelve atmospheric VOCs, meteorological factors, and daily deaths for stroke and its subtypes (including ischemic and hemorrhagic stroke) in Guangzhou from 2020 to 2021 were collected. The time-series Poisson generalized additive model was established to analyze the relationship between daily average concentrations of atmospheric VOCs and daily mortality from a stroke on different lag days. The season, gender, and age group further performed stratification analysis. Results: Toluene and n-pentane were associated with a higher mortality risk from stroke and its subtypes. For each interquartile range (IQR) increment in toluene concentration at lag0- 1 days, the RRs for mortality from stroke and hemorrhagic stroke were 1.060 (95%CI: 1.036-1.085) and 1.071 (95%CI: 1.030-1.113), respectively. For each IQR increment in n-pentane concentration, the RR for mortality from ischemic stroke was 1.064 (95%CI: 1.030-1.099). The effect estimates of VOCs may be higher during the cold season and among women and people aged ≥75 years. For each IQR increment in toluene concentration, the RRs for mortality risk of stroke in the cold season and women were 1.099 (95%CI: 1.056-1.143) and 1.085 (95%CI: 1.050-1.120), respectively. For n-pentane, the RR for death risk of stroke in people aged ≥75 years old was 1.072 (95%CI: 1.036-1.109). Results of sensitivity analysis showed that the effect estimates fluctuated less when PM2.5 and O3 were separately introduced for the two-pollutant model, as well as changing the degrees of freedom for covariates. Conclusions: This study suggests that VOCs may be an independent risk factor for daily mortality from stroke. Moreover, Toluene presented the most significant health impact.

Development and validation of a multiphase CT radiomics nomogram for the preoperative prediction of lymphovascular invasion in patients with gastric cancer

AIM

To develop a nomogram to predict lymphovascular invasion (LVI) in gastric cancer by integrating multiphase computed tomography (CT) radiomics and clinical risk factors.

MATERIALS AND METHODS

One hundred and seventy-two gastric cancer patients (121 training and 51 validation) with preoperative contrast-enhanced CT images and clinicopathological data were collected retrospectively. The clinical risk factors were selected by univariate and multivariate regression analysis. Radiomic features were extracted and selected from the arterial phase (AP), venous phase (VP), and delayed phase (DP) CT images of each patient. Clinical risk factors, radiomic features, and integration of both were used to develop the clinical model, radiomic models, and nomogram, respectively.

RESULTS

Radiomic features from AP (n=6), VP (n=6), DP (n=7) CT images and three selected clinical risk factors were used for model development. The nomogram showed better performance than the AP, VP, DP, and clinical models in the training and validation datasets, providing areas under the curves (AUCs) of 0.890 (95% CI: 0.820-0.940) and 0.885 (95% CI:0.765-0.957), respectively. All models indicated good calibration, and decision curve analysis proved that the net benefit of the nomogram was superior to that of the clinical and radiomic models throughout the vast majority of the threshold probabilities.

CONCLUSIONS

The nomogram integrating multiphase CT radiomics and clinical risk factors showed favourable performance in predicting LVI of gastric cancer, which may benefit clinical practice.

[Analysis of curative effect and short-term survival rate of plasma exchange and double plasma molecular adsorption combined with half-volume plasma exchange in the treatment of liver failure]

Objective: To investigate how plasma exchange (PE) and double plasma molecular adsorption combined with half-volume plasma exchange (DPMAS + half-volume PE) affect the curative effect and short-term survival rate in liver failure. Methods: Data from 181 cases of liver failure caused by different etiologies from January 1, 2017 to September 31, 2020, were selected. Patients were divided into a PE treatment alone group and a DPMAS + half-dose PE treatment group. The laboratory indicators with different models of artificial liver before and after treatment and the survival rates of 7, 14, 28, and 90 days after discharge were observed in the two groups. Measurement data were analyzed by t-tests and rank sum tests. Categorical data were analyzed by χ (2) test. Results: Non-biological artificial liver therapy with different models improved the liver and coagulation function in the two groups of patients with liver failure (P < 0.05 in PTA% intra-group). The coagulation function was significantly improved in the PE treatment alone group compared with that in the DPMAS + half-dose PE group [PT after treatment: (20.15 ± 0.88) s in the PE treatment alone group, (23.43 ± 1.02) s, t = -2.44, P = 0.016 in the DPMAS+half-dose PE group; PTA: 44.72% ± 1.75% in the PE treatment alone group, 35.62% ± 2.25%, t = 3.215 P = 0.002 in the DPMAS + half-dose PE group]. Bilirubin levels were significantly decreased in the DPMAS+half-dose PE group compared to the PE treatment alone group [total bilirubin after treatment: (255.30 ± 15.64) μmol/L in the PE treatment alone group, (205.46 ± 9.03) μmol/L, t = 2.74, P = 0.07 in the DPMAS + half-dose PE group; direct bilirubin after treatment: (114.74 ± 7.11) μmol/L in the PE treatment alone group, (55.33 ± 3.18) μmol/L, t = 7.54, P < 0.001) in the DPMAS + half-dose PE group]. However, there was no significant effect on leukocytes and neutrophils after treatment with different models of artificial liver (P > 0.05) in the two groups, and platelets decreased after treatment, with no statistically significant difference between the groups (t = -0.15, P = 0.882). The inflammatory indexes of the two groups improved after treatment with different models of artificial liver (P < 0.05], and the 28 and 90 d survival rates were higher in the DPMAS+half-dose PE group than those of the PE treatment alone group (28 d: 60.3% vs. 75.0%, χ (2) = 4.315, P = 0.038; 90 d: 56.2% vs. 72.5%. χ (2) = 10.355 P < 0.001). DPMAS + half-dose PE group plasma saving was 1385 ml compared with PE treatment alone group (Z = -7.608, P < 0.05). Conclusion: Both DPMAS+half-dose PE and PE treatment alone have a certain curative effect on patients with liver failure. In DPMAS+half-dose PE, the 28-day survival rate is superior to PE treatment alone, and it saves plasma consumption and minimizes blood use in clinic.

[Analysis of clinicopathological features of 18 cases of hepatic angiosarcoma]

Objective: To investigate the clinicopathological features, treatment, and prognosis of hepatic angiosarcoma. Methods: Clinicopathological data and prognostic conditions of 18 cases with hepatic angiosarcoma were collected retrospectively. The recurrence-free survival rate and overall survival rate were calculated by the Kaplan-Meier method. A Cox regression analysis was used to explore the survival-related risk factors. Results: There were 12 male and 6 female patients, with an average age of 57 (37 ~ 70) years. The tumor's average diameter was 8.40 (2.00 ~ 18.00) cm. Seven cases had multiple tumors, while two cases had large vessel tumor thrombuses. Microscopically, the tumor tissues were irregularly anastomosed, with vascular lacunar or solid bundle-like weaving, and the tissue morphology mimicked capillary hemangioma, cavernous hemangioma, or angioepithelioma, while tumor cells were spindle-shaped or epithelioid, lined with hobnails in the lumen, or formed papillary structures in the lumen. The proportion of highly, moderately, and poorly differentiated tumors was 4:8:6, with six cases having clear tumor boundaries, eight having microvascular tumor thrombi, and sixteen having blood lake formation. Different levels of expression of CD31, CD34, erythroblast transformation-specific related genes, and Fli-1 markers were demonstrated in all of the cases. Four cases had a P53 mutation, and six cases had Ki-67 > 10%. During the follow-up period of 0.23-114.20 months, the five-year recurrence-free survival rate and overall survival rate were 16.7% and 37.2%, respectively. Cox regression multivariate analysis showed that preoperative symptoms and multiple tumors were significant risk factors for recurrence-free survival, while preoperative symptoms and Ki-67 > 10% were significant risk factors for overall survival. Conclusion: Hepatic angiosarcoma is a rare hepatic mesenchymal tumor with high malignancy and a poor prognosis. Pathological morphology and immunohistochemical marker combinations are needed for a definite diagnosis. However, the complexity of angiosarcomas' histological and cytological conformations and the overlap of pathological features with benign vascular tumors, sarcomas, and carcinomas pose difficulties in the differential diagnosis. Thus, the only effective ways to prolong survival are early detection and radical surgical resection.

[Value of Improved Mayo Endoscopic Score for evaluating treatment efficacy for active ulcerative colitis]

OBJECTIVE

To assess the value of Improved Mayo Endoscopic Score (IMES) for evaluation of treatment efficacy for active ulcerative colitis (UC).

METHODS

We retrospectively analyzed the clinical and endoscopic data of 103 patients diagnosed with active UC in Beijing Tsinghua Changgung Hospital from January, 2015 to December, 2020. The severity of endoscopic lesions was determined by Mayo Endoscopic Score and the Ulcerative Colitis Endoscopic Index of Severity (UCEIS), and the area of the endoscopic lesions was evaluated based on the Montreal classification system. The IMES was established by combining the MES with the Montreal classification.

RESULTS

Univariate analysis suggested that young patients (<40 years old), patients with extensive disease type (E3), patients with high endoscopic scores (MES=3, UCEIS>4, and IMES>4), and patients receiving advanced drug therapy (with systemic hormones, immunosuppressants, immunomodulators, and biological agents, etc.) had lower clinical and endoscopic remission rates. COX survival analysis showed that IMES≤4 was an independent risk factor for clinical and endoscopic remission. ROC curve indicated that the predictive value of IMSE≤4 for clinical and endoscopic remission (AUC=0.7793 and 0.7095, respectively; P<0.01) was better than that of Montreal (AUC=0.7357 and 0.6847, respectively; P<0.01), MES=2 (AUC=0.6671 and 0.5929, respectively; P<0.01), and UCEIS≤4 (AUC=0.6823 and 0.6459, respectively; P<0.01); IMES=5 had a better predictive value for patients with active UC undergoing colectomy tham E3 and MES=3.

CONCLUSION

IMES has good value in evaluating treatment efficacy for active UC.

Enhancement of blue and ultraviolet components in PCF-based supercontinuum generation through inter-modal dispersive-wave radiation

Broadband supercontinuum (SC) light sources generated through nonlinear effects in solid-core photonic crystal fibers (PCFs) have been widely used in spectroscopy, metrology, and microscopy, leading to great application successes. The short-wavelength extension of such SC sources, a longstanding challenge, has been the subject of intensive study over the past two decades. However, the exact mechanism of blue and ultraviolet light generation, especially for some resonance spectral peaks in the short-wavelength regime, is not yet fully understood. Here, we demonstrate that the effect of inter-modal dispersive-wave radiation, which results from phase matching between pump pulses at the fundamental optical mode and packets of linear waves at some higher-order modes (HOMs) propagating in the PCF core, might be one of the critical mechanisms that can result in some resonance spectral components with wavelengths much shorter than that of the pump light. We observed in an experiment that several spectral peaks resided in the blue and ultraviolet regimes of the SC spectrum, whose central wavelengths can be tuned by varying the PCF-core diameter. These experimental results can be interpreted well using the inter-modal phase-matching theory, providing some useful insights into the SC generation process.

[Exploration of making removable partial denture by digital technology]

To explore the digital manufacturing process of distal extension removable partial denture. From November 2021 to December 2022, 12 patients (7 males and 5 females) with free-ending situation were selected from the Department of Prosthodontics, School of Stomatology, The Fourth Military Medical University. Three-dimensional model of the relationship between alveolar ridge and jaw position was obtained by intraoral scanning technique. After routine design, manufacturing and try-in of metal framework for removable partial denture, the metal framework was located in the mouth and scanned again to obtain the composite model of dentition, alveolar ridge and metal framework. The free-end modified model is obtained by merging the digital model of free-end alveolar ridge with the virtual model with the metal framework. The three-dimensional model of artificial dentition, and base plate was designed on the free-end modified model, and the resin model were made by digital milling technology. The removable partial denture was made by accurately positioning the artificial dentition and base plate, bonding metal framework with injection resin, grinding and polishing the artificial dentition and resin base. Compared with the design data after clinical trial, the results showed that there was an error of 0.4-1.0 mm and an error of 0.03-0.10 mm in the connection between the resin base of artificial dentition and the connecting rod of the in-place bolt and the connection between artificial dentition and resin base. After denturen delivery, only 2 patients needed grinding adjustment in follow-up visit due to tenderness, and the rest patients did not find any discomfort. The digital fabrication process of removable partial denture used in this study can basically solve the problems of digital fabrication of free-end modified model and assembly of artificial dentition with resin base and metal framework.

Dexmedetomidine-mediated neuroprotection against sevoflurane-induced brain development abnormality in fetal mice brain

OBJECTIVE

Brain development is susceptible to external influences during the gestation period so the neurotoxicity of anesthetics has gained a lot of attention. We aimed to investigate the neurotoxicity of sevoflurane to fetal mice brain as well as the neuroprotective effects of dexmedetomidine.

MATERIALS AND METHODS

Pregnant mice were treated with 2.5% sevoflurane for 6 hours. The changes in fetal brain development were assayed with immunofluorescence and western blot. The pregnant mice were intraperitoneally injected with dexmedetomidine or vehicle from gestation day (G) 12.5 to G15.5.

RESULTS

Our results showed maternal sevoflurane exposure could not only inhibit neurogenesis but also lead to precocious generation of astrocytes in fetal mice brains. The fetal mice brain of sevoflurane group exhibited a significant inhibition in the activity of Wnt signaling and the expression of CyclinD1, Ngn2. Chronic dexmedetomidine administration could minimize the negative effects caused by sevoflurane by activating the Wnt signaling pathway.

CONCLUSIONS

This study has uncovered a Wnt signaling-related mechanism of the neurotoxicity of sevoflurane and confirmed the neuroprotective effect of dexmedetomidine, which could provide pre-clinical evidence for clinical decision-making.

High Electron Mobility Hot-Exciton Induced Delayed Fluorescent Organic Semiconductors

The development of high mobility emissive organic semiconductors is of great significance for the fabrication of miniaturized optoelectronic devices, such as organic light emitting transistors. However, great challenge exists in designing key materials, especially those who integrates triplet exciton utilization ability. Herein, dinaphthylanthracene diimides (DNADIs), with 2,6-extended anthracene donor, and 3'- or 4'-substituted naphthalene monoimide acceptors were designed and synthesized. By introducing acceptor-donor-acceptor structure, both materials show high electron mobility. Moreover, by fine-tuning of substitution sites, good integration with high solid state photoluminescence quantum yield of 26 %, high electron mobility of 0.02 cm²  V^-1  s^-1 , and the feature of hot-exciton induced delayed fluorescence were obtained in 4'-DNADI. This work opens a new avenue for developing high electron mobility emissive organic semiconductors with efficient utilization of triplet excitons.

Propagation strategies of Deyeuxia angustifolia in heterogeneous habitats

Plants utilize different strategies in different environments to maximize population expansion. Understanding plant reproductive strategies in heterogeneous habitats is therefore important for explaining plant ecological adaptability, and for effectively managing and conserving ecosystems. We wanted to explore the reproductive strategy transformation of D. angustifolia in heterogeneous habitats, as well as the environmental factors driving and affecting its reproductive characteristics. To do this we measured the reproductive characteristics of D. angustifolia, as well as the soil physical and chemical properties of these heterogeneous habitats. The density, biomass per unit area, and proportion of aboveground biomass in swampy meadows were significantly higher compared to other habitats. The proportion of rhizome node buds gradually increased from swampy to typical to miscellaneous grass meadows, while the proportion of tillering node buds decreased. The allocation of sexual reproduction within D. angustifolia populations was significantly and positively correlated with plant rhizome biomass and negatively correlated with the number of tillering node buds. The propagation strategies of D. angustifolia in heterogeneous habitats were consistent with CSR theory (Competitor, Stress-tolerator, and Ruderal). The proportions of inflorescence (2.07 ± 0.52%; 1.01 ± 0.15%) and root (23.8 ± 1.5%; 19.6 ± 1.4%) biomass in miscellaneous and typical meadows were high, which tended toward the “Ruderal” adaptation strategy. In swampy meadow, D. angustifolia invested mostly in vegetative growth to produce tiller node buds (14426.67 buds/m2; 46%) and ramets (1327.11 ± 102.10 plants/m2), which is characteristic of the “Competitor” strategy. Swamp D. angustifolia resisted flooding by maintaining a resource balance in its body, and was therefore biased toward the “Stress-tolerator” strategy. Environmental factors accounted for 74.63% of reproductive characteristic variation, in which the interpretative proportions of soil water content, dissolved organic carbon, ammonia nitrogen, and nitrate nitrogen were significant (p &lt; 0.01). When soil water content, dissolved organic carbon, and nitrate nitrogen increased, D. angustifolia tended toward the C strategy; in contrast, when soil water content decreased, amine nitrogen and available phosphorus increased, and D. angustifolia tended toward the R strategy. In a stressful environment, the escape mechanism constitutes an increased rhizome and sexual reproduction investment. In contrast, for suitable habitats, tillering node buds increased in order to expand the population via new plant production, which was the propagation strategy of D. angustifolia in heterogeneous habitats.

[Impact of interventional therapy on top of standard drug therapy on left ventricular structure and function in HFrEF patients complicating with middle aortic syndrome caused by Takayasu arteritis]

Objective: To evaluate the impact of interventional therapy on top of drug therapy on cardiac function and structure in heart failure with reduced ejection fraction (HFrEF) patients complicating with middle aortic syndrome caused by Takayasu arteritis (TA-MAS). Methods: It was a retrospective longitudinal study. The data of patients with TA-MAS and HFrEF, who received interventional therapy on top of drug therapy in Fuwai Hospital from January 2010 to September 2020, were collected and analyzed. Baseline clinical data (including demographic data, basic treatment, etc.) were collected through the electronic medical record system. Changes of indexes such as New York Heart Association (NYHA) classification, N-terminal pro-brain natriuretic peptide (NT-proBNP), left ventricular end diastolic diameter (LVEDD), left ventricular ejection fraction (LVEF), left ventricular mass index (LVMI) before and after therapy were analyzed. Results: A total of 10 patients were collected. There were 8 females in this patient cohort, age was (18.4±5.0) years and onset age was (15.3±5.0) years. All 10 patients received standard heart failure medication therapy in addition to hormone and/or immunosuppressive anti-inflammatory therapy, but cardiac function was not improved, so aortic balloon dilatation and/or aortic stenting were performed in these patients. The median follow-up was 3.3(1.3, 5.6) years. On the third day after interventional therapy, the clinical symptoms of the 10 patients were significantly improved, NYHA classfication was restored from preoperative Ⅲ/Ⅳ to Ⅱ at 6 months post intervention(P<0.05). Compared with preoperation, NT-proBNP (P=0.028), LVEDD (P=0.011) and LVMI (P=0.019) were significantly decreased, LVEF was significantly increased (P<0.001) at 6 months after operation. Compared with preoperation, NT-proBNP (P=0.016), LVEDD (P=0.023) and LVMI (P=0.043) remained decreased, LVEF remained increased (P<0.001) at 1 year after operation. Conclusion: Results from short and medium term follow-up show that interventional therapy on top of heart failure drug therpay can effectively improve left cardiac function and attenuate cardiac remodeling in patients with TA-MAS comorbid with HFrEF.

[Risk factors analysis on high-risk behaviors of drowning among students in Shufu county, Kashgar area, Xinjiang Uygur Autonomous Region]

Objective: To understand the incidence and risk factors of high-risk drowning behaviors among primary and middle school students in Shufu county, Kashgar area, Xinjiang Uygur Autonomous Region, and provide a theoretical basis for the development of drowning prevention policies and intervention measures. Methods: Cluster random sampling method was adopted in Bulakesu and Uppal of Shufu county. A total of 28 primaries and 2 middle schools were selected, and questionnaires surveyed all the students in grades 1-8. Results: A total of 14 543 questionnaires were sent out. 23.9% of primary and secondary school students had experienced high-risk drowning behavior in the past 12 months. Higher swimming level, introversion, intense curiosity, poor relationship with classmates, poor relationship with family, and open water near the school and open water near home were the risk factors of high-risk drowning behaviors. Conclusions: More attention should be paid to the psychology and high-risk behaviors of primary and middle school students, and the education of drowning knowledge and skills should be strengthened. Meanwhile, schools and communities should pay attention to the management and intervention of open water.

[Health-adjusted life expectancy in residents in Guangzhou, 2010-2019]

Objective: To analyze the spatiotemporal distribution of life expectancy (LE) and health-adjusted life expectancy (HALE) in Guangzhou from 2010 to 2019, and quantize the comprehensive impact of different causes and sequelae on health. Methods: The LE, HALE, and cause-excluded health adjusted life expectancy (CEHALE) were estimated using cause-of-death surveillance datasets from Guangzhou Municipal Center for Disease Control and Prevention from 2010 to 2019 and open data from the Global Burden of Disease Study. Joinpoint log-linear regression model was used to analyze the temporal trend and described spatial distribution. Results: In 2019, the LE in residents in Guangzhou was 82.9 years (80.1 years in men and 85.9 years in women), and the HALE was 75.6 years (74.0 years in men and 77.3 years in women). Compared with the urban fringe, the central urban area had higher LE and HALE, and the differences between LE and HALE were small. The LE and HALE in Guangzhou showed an increasing trend from 2010 to 2019. The LE increased by 2.8 years (AAPC=0.4, 95%CI: 0.3-0.4), with the increase of 2.8 years in men and 2.9 years in women. The HALE increased by 2.4 years (AAPC=0.3, 95%CI: 0.3-0.4), with the increase of 2.5 years in men and 2.2 years in women. The median healthy life lost due to communicable, maternal, neonatal, and nutritional diseases was 6.2 years (AAPC=-4.2, 95%CI: -5.3--3.1), while the median healthy life lost due to non-communicable diseases was 14.7 years (AAPC=1.6, 95%CI: 0.9-2.3), the median healthy life expectancy reduced by injury was 6.3 years (AAPC=-3.5, 95%CI: -4.5--2.6). Musculoskeletal disorders, skin and subcutaneous diseases, cardiovascular diseases, nutritional deficiencies, diabetes and kidney diseases were the top five diseases causing healthy life expectancy loss. Conclusion: The LE and HALE in residents in Guangzhou increased steadily from 2010 to 2019, but the quality of life in the urban fringe was lower than that of the central urban area. Non-communicable diseases were the leading causes of healthy life expectancy loss. Health policies and prevention measures should be developed according to area specific characteristics, and social medical resources should be rationally allocated to key diseases to reduce their disease burden.

[Phenotypes and genotypes of 78 patients with propionic acidemia]

Objective: Propionic acidemia is a rare inherited metabolic disorder caused by propionyl CoA carboxylase (PCC) deficiency. This study aims to analyze the clinical characteristics and gene variations of Chinese patients with propionic acidemia, and to explore the correlation between clinical phenotypes and genotypes. Methods: Single-center, retrospective and observational study. Seventy-eight patients of propionic acidemia (46 males and 32 females) from 20 provinces and autonomous regions were admitted from January 2007 to April 2022. Their age of initial diagnosis ranged from 7 days to 15 years. The clinical manifestations, biochemical and metabolic abnormalities, genetic variations, diagnosis, treatment and outcome were studied. Chi-Square test or Mann-Whitney U test were used for statistical analysis. Results: Among 78 cases, 6 (7.7%) were identified by newborn screening; 72 (92.3%) were clinically diagnosed after onset, and the age of onset was 2 hours after birth to 15 years old; 32 cases had early-onset disease and 40 cases had late-onset disease. The initial manifestations included lethargy, hypotonia, vomiting, feeding difficulties, developmental delay, epilepsy, and coma. Among the 74 cases who accepted gene analysis, 35 (47.3%) had PCCA variants and 39 (52.7%) had PCCB variants. A total of 39 PCCA variants and 32 PCCB variants were detected, among which c.2002G>A and c.229C>T in PCCA and c.838dupC and c.1087T>C in PCCB were the most common variants in this cohort. The variants c.1228C>T and c.1283C>T in PCCB may be related to early-onset type. The variants c.838dupC, c.1127G>T and c.1316A>G in PCCB, and c.2002G>A in PCCA may be related to late-onset disease. Six patients detected by newborn screening and treated at asymptomatic stage developed normal. The clinically diagnosed 72 cases had varied complications. 10 (12.8%) cases of them died. 62 patients improved after metabolic therapy by L-carnitine and diet. Six patients received liver transplantation because of recurrent metabolic crisis. Their clinical symptoms were markedly improved. Conclusion: The clinical manifestations of propionic acidemia are complex and lack of specificity. Newborn screening and high-risk screening are keys for early treatment and better outcome. The correlation between the genotype and phenotype of propionic acidemia is unclear, but certain variants may be associated with early-onset or late-onset propionic acidemia.

[Two cases of herpes simplex keratitis after trans-epithelial photorefractive keratectomy]

We herein report 2 cases of herpes simplex keratitis after trans-epithelial photorefractive keratectomy. Patients' medical histories, symptoms, signs, clinical examination results, diagnosis and treatment were showed in detail. Following precision diagnosis and medical intervention, including topical and systemic antiviral treatmented for 1 to 2 weeks. The two patients were cured with full reepithelialization without corneal scar.

Menopausal hormone therapy: what are the problems in the perception of Chinese physicians?

OBJECTIVE

This study aimed to investigate Chinese physicians' perception and attitudes toward menopausal hormone therapy (MHT).

METHODS

This nationwide online survey was conducted in China. Physicians registered in the WeChat groups of the Gynecological Endocrinology Committee of China's Maternal and Child Health Care Association received a message invitation to complete this anonymous online survey from April 2020 to July 2020. Physicians' knowledge of and attitudes toward MHT were surveyed.

RESULTS

In total, 4672 questionnaires were submitted; only completed questionnaires could be submitted. The message was sent to 6021 doctors, so the response rate was 77.6%. Overall, 77.9-92.9% of physicians knew the common indications and contraindications to MHT. Additionally, 90.6%, 85.4%, 80.7% and 37.5% of physicians thought that MHT would increase the risk of venous thrombosis, breast cancer, endometrial cancer and weight gain, respectively. In total, 58.1% of the physicians mistakenly believed that a sex hormone test was one of the necessary examinations to reassess MHT prescription during follow-up visits. We found that 68.5% of physicians would consider using MHT themselves or recommend MHT to their partners in the future, and 11.4% were currently using MHT.

CONCLUSIONS

Most Chinese physicians have basic knowledge of MHT. Their misunderstandings about MHT mainly centered on the risks of endometrial cancer, weight gain and the necessary examinations during follow-up visits. These misunderstandings need to be clarified in future professional training programs.

[Research advances on signaling pathways affecting sweat gland development and their involvement in the reconstitution of sweat adenoid cells in vitro]

The damage of sweat glands in patients with extensive deep burns results in the loss of thermoregulation, which seriously affects the quality of life of patients. At present, there are many researches on the repair of sweat gland function, but the mechanism of human sweat gland development has not been fully clarified. More and more studies have shown that the cascaded pathways of Wnt/β-catenin, ecto- dysplasin A/ectodysplasin A receptor/nuclear factor-κB, sonic hedgehog, and forkhead box transcription factor jointly affect the development of sweat glands, and it has been reported that the cascaded signaling pathways can be used to achieve the reconstruction of sweat adenoid cells in vitro. This article reviews the signaling pathways that affect the development of sweat glands and their involvement in the reconstruction of sweat adenoid cells in vitro.

[Epidemiological characteristics of three local epidemics of COVID-19 in Guangzhou]

Objective: To understand the epidemiological characteristics of three local COVID-19 epidemics in Guangzhou and provide reference for optimizing strategies and measures of COVID-19 prevention and control. Methods: The data of local COVID-19 cases in Guangzhou reported as of June 18, 2021 were collected from National Notifiable Disease Report System of China. The software Excel 2019 and SPSS 22.0 were applied for data cleaning and statistical analysis. Results: A total of 726 COVID-19 cases were reported in the three local epidemics in Guangzhou. In the epidemic associated with the outbreak of COVID-19 in Hubei province, 366 cases were reported. Most cases were female (51.6%, 189/366), aged 18-65 years (81.4%, 298/366), jobless/unemployed (32.2%, 118/366) and retired persons (20.2%,74/366). The initial symptoms of most cases were fever (71.6%, 250/349) and cough (60.7%, 212/349). In the epidemic associated with the imported COVID-19 cases from Africa, 207 cases were reported. Most cases were aged 18-40 years (72.9%, 151/207), male (69.6%, 144/207), and engaged in commercial services (62.3%,129/207). The initial symptoms of most cases were no obvious discomfort (55.6%, 15/27) and cough (37.0%, 10/27). In the epidemic associated with Delta variant of SARS-CoV-2, 153 cases were reported, in which women accounted for 58.8% (90/153), most cases were over 41 years old (64.7%,99/153), and retired persons accounted for the highest proportion (32.0%,49/153). The initial symptoms of most cases were cough (32.9%, 48/146) and no obvious discomfort (28.1%, 41/146). The household secondary attack rates of the three local epidemics were 11.2%, 5.7% and 11.5%, respectively. The median (P₂₅, P₇₅) of incubation periods were 6.5 (4.0,10.8) d, 4.0 (2.5, 6.0) d and 4.0 (3.0,5.0) d. The serial intervals median (P₂₅, P₇₅) were 4.0 (3.0, 8.0) d, 4.0 (2.5, 6.0) d and 3.0 (2.0,5.0) d. There were significant differences in gender, age, occupation, initial symptoms, household secondary attack rate and incubation period among the three local COVID-19 epidemics (all P<0.05). In the proportion of the case finding way, passive detection in patient treatment were mainly 44.3%(162/366) in the epidemic associated with the outbreak of COVID-19 in Hubei province,but active community case screening [58.5% (121/207) and 27.5% (24/153)] and close contact management in imported case were mostly [33.3% (69/207) and 67.3% (103/153)] in the epidemic associated with the imported COVID-19 cases from Africa and with Delta variant of SARS-CoV-2, respectively. Conclusions: Due to the different sources of infection, strain types and prevention and control strategies, the epidemiological characteristics of the three local COVID-19 epidemics in Guangzhou differed in demographics, clinical symptoms, transmission routes and case finding, which suggested that it is necessary to improve the key population and common symptom monitoring in the routine prevention and control of COVID-19 to prevent the reemerge of the epidemic.

Immune signatures underlying post-acute COVID-19 lung sequelae

[Figure: see text].

Biofunctional magnesium-coated Ti6Al4V scaffolds promote autophagy-dependent apoptosis in osteosarcoma by activating the AMPK/mTOR/ULK1 signaling pathway

The recurrence of osteosarcoma (OS) after reconstruction using Ti6Al4V prostheses remains a major problem in the surgical treatment of OS. Modification of the surfaces of Ti6Al4V prostheses with antitumor functions is an important strategy for improving therapeutic outcomes. Magnesium (Mg) coating has been shown to be multifunctional: it exhibits osteogenic and angiogenic properties and the potential to inhibit OS. In this study, we determined the proper concentration of released Mg²⁺ with respect to OS inhibition and biosafety and evaluated the anti-OS effects of Mg-coated Ti6Al4V scaffolds. We found that the release of Mg²⁺ during short-term and long-term degradation could significantly inhibit the proliferation and migration of HOS and 143B cells. Increased cell apoptosis and excessive autophagy were also observed, and further evidence of AMPK/mTOR/ULK1 signaling pathway activation was obtained both in vitro and in vivo, which suggested that the biofunctional scaffolds induce OS inhibition. Our study demonstrates the ability of an Mg coating to inhibit OS and may contribute to the further application of Mg-coated Ti6Al4V prostheses.

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Multifunctional Mg coating is considerable surface modification for Ti6Al4V prostheses.

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Mg²⁺ releasing by the scaffolds could significantly inhibit the proliferation and migration of OS cells.

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The biofunctional scaffolds could inhibit OS by activating autophagy-dependent apoptosis.

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The AMPK/mTOR/ULK-1 pathway was involved in autophagy-depended apoptosis induced by the scaffolds.

[Clinical and genetic studies on 76 patients with hydrocephalus caused by methylmalonic acidemia combined with homocysteinuria]

Objective: To analyze the clinical features, genetic characteristics, treatment and follow-up results of patients with hydrocephalus caused by methylmalonic acidemia combined with homocysteinuria, and to discuss the optimal strategies for assessing and treating such patients. Methods: From January 1998 to December 2020, 76 patients with hydrocephalus due to methylmalonic acidemia combined with homocysteinuria in the Department of Pediatrics in 11 hospitals including Peking University First Hospital were diagnosed by biochemical, genetic analysis and brain imaging examination. The patients were divided into operation-group and non-operation-group according to whether they underwent ventriculoperitoneal shunt. The clinical features, laboratory examinations, genotype, and follow-up data were retrospectively analyzed. Data were compared between the two groups using rank sum test, and categorical data were compared using χ² test. Results: Among the 76 patients (51 male, 25 female), 5 were detected by newborn screening, while 71 were diagnosed after clinical onset, 68 cases (96%) had early-onset, 3 cases (4%) had late-onset. The most common clinical manifestations of 74 cases with complete data were psychomotor retardation in 74 cases (100%), visual impairment in 74 cases (100%), epilepsy in 44 cases (59%), anemia in 31 cases (42%), hypotonia or hypertonia in 21 cases (28%), feeding difficulties in 19 cases (26%) and disturbance of consciousness in 17 cases (23%). Genetic analysis was performed in 76 cases, all of whom had MMACHC gene variations, including 30 homozygous variations of MMACHC c.609G>A. The most common variations were c.609G>A (94, 62.7%), followed by c.658_660del (18, 12.0%), c.567dupT (9, 6.0%) and c.217C>T (8, 5.3%). Therapy including cobalamin intramuscular injection, L-carnitine and betaine were initiated immediately after diagnosis. A ventriculoperitoneal shunt operation was performed in 41 cases (operation group), and 31 patients improved after metabolic intervention (non-operation group). There was no significant difference in the age of onset, the age of diagnosis, the blood total homocysteine, methionine, and urinary methylmalonic acid concentration between the two groups (all P>0.05). The symptoms of psychomotor development, epilepsy, and visual impairments improved gradually after a long-term follow-up in the operation group. Conclusions: Hydrocephalus is a severe complication of methylmalonic acidemia combined with homocysteinuria. The most common clinical manifestations are psychomotor retardation, visual impairment, and epilepsy. It usually occurs in early-onset patients. Early diagnosis and etiological treatment are very important. Hydrocephalus may improve after metabolic intervention in some patients. For patients with severe ventricular dilatation, prompt surgical intervention can improve the prognosis.

[Establishment of animal models of epidermal growth factor receptor inhibitor-related rashes]

OBJECTIVE

To establish animal models epidermal growth factor receptor inhibitor-related skin rashes using cetuximab, gefitinib or erlotinib.

OBJECTIVE

Female SCID mice were randomly divided into blank control group and high-, moderate-, and low-dose cetuximab groups. The mice in control group received intraperitoneal injection of saline, and those in the 3 cetuximab groups were injected with 80, 40, and 20 mg/kg cetuximab (3 times a week for 4 weeks), respectively. The general skin appearance and skin pathologies of the mice were observed. Female BN rats were randomly divided into blank group, ovalbumin group, gefitinib group and erlotinib group, and in the latter 3 groups, the rats were given ovalbumin (1 mg), gefitinib (37.5 mg/kg), and erlotinib (23.5 mg/kg) by lavage once daily for 45 days, respectively. Skin pathologies of the rats were observed, and serum levels of TNF-α, IL-6 and other inflammatory factors were detected using ELISA.

OBJECTIVE

Intraperitoneal injection of cetuximab did not induce typical skin rashes, scabs or obvious skin inflammation in the mice. In female BN rats, lavage of gefitinib caused obvious skin rashes, scabs and exudation, and obvious inflammatory cell infiltration, keratinosis, spinous layer release and epidermal thickening were observed in the skin. No obvious skin inflammation were observed in the rats in the control, ovalbumin or erlotinib groups. While IgE (P=0.061) and TNF-α concentrations (P=0.057) did not differ significantly among the groups, serum levels of IL-6 was significantly higher in gefitinib group than in the blank control group (P=0.016) but similar between erlotinib group and the blank group (P=0.910).

OBJECTIVE

Intraperitoneal injection of cetuximab can not induce epidermal growth factor receptor inhibitor-related skin rashes in SCID mice. Lavage of gefitinib, but not erlotinib, can be used to establish models of epidermal growth factor receptor inhibitor-related rashes in BN rats.

The significance of phase reversion-induced nanograined/ultrafine-grained (NG/UFG) structure on the strain hardening behavior and deformation mechanism in copper-bearing antimicrobial austenitic stainless steel

The unique concept of phase reversion involving severe deformation of parent austenite into martensite, followed by annealing for a short duration, whereby the strain-induced martensite reverts to austenite, was adopted to obtain nano-grained/ultrafine-grained (NG/UFG) structure in a Cu-bearing biomedical austenitic stainless steel resulting in high strength-high ductility combination. Work hardening and accompanying deformation mechanism are two important aspects that govern the mechanical behavior of biomedical devices. Thus, post-mortem electron microscopy of the strained region was carried out to explore the differences in the deformation mechanisms induced by grain refinement, while the strain hardening behavior was analyzed by Crussard-Jaoul (C-J) analysis of the tensile stress-strain data. The strain hardening behavior consisted of four stages and was strongly affected by grain structure. Twinning-induced plasticity (TWIP) was the governing deformation mechanism in the NG/UFG structure and contributed to good ductility. In striking contrast, transformation-induced plasticity (TRIP) contributed to high ductility in the coarse-grained (CG) counterpart and was the governing strain hardening mechanism. When the grain size is less than ~1 μm, the increase in the strain energy and the austenite stability significantly reduce the possibility of strain-induced martensite transformation such that there is a distinct transition in deformation mechanism from nanoscale twinning in the NG/UFG structure to strain-induced martensite in CG structure. The differences in the deformation mechanisms are explained in terms of austenite stability - strain energy relationship.

Analysis of factors leading to lid wiper epitheliopathy

OBJECTIVE

Lid wiper epitheliopathy (LWE) has received more attention during the diagnosis and treatment of the dry eye. However, its causes and pathogenesis remain unclear. We aimed to explore the etiology of LWE by analyzing the association between the severity of LWE and different anatomical and tissue morphological examination characteristics using confocal microscopy on eyes with dry eye syndrome.

PATIENTS AND METHODS

We recruited 350 patients with LWE and dry eye syndrome (350 eyes). We examined the eyes with lid-wiper staining, conjunctival staining, a comprehensive ocular surface exam using the OCULUS keratography 5M, conjunctival impression cytology, and confocal microscopy observations. We analyzed the associations between each indicator and the LWE staining score.

RESULTS

According to the Spearman's analysis, the LWE staining score was weakly associated with thickness of the lipid layer (r=0.1737, p=0.0005) and severity of Meibomian gland dysfunction (r=0.2026, p<0.0001); and strongly associated with staging of conjunctival impression cytology (r= -0.7694, p<0.0001). Pearson's correlation analysis indicated that, LWE staining score was moderately associated with age (r=0.4165, p<0.0001), tear meniscus height (r=0 -0.4019, p<0.0001), and NIKBUT-first (noninvasive keratography tear film breakup time) (r= -0.5108, p<0.0001); and strongly associated with NIKBUT-average (r= -0.7820, p<0.0001) and ocular staining score (r=0.6113, p<0.00001). Some patients presented abnormal blinking. We observed deeper lesion depths and more holes and fissures in the lid wipers of patients with more severe LWE than in patients with milder LWE.

CONCLUSIONS

Abnormal friction factors caused by insufficient lubrication between the lid wiper area and the ocular surface seem to influence the development and/or the severity of LWE. Aggravation of LWE further increases the frictional damage between the lid wiper and the ocular surface.

Comparative genome-wide methylation analysis of longissimus dorsi muscles in Yorkshire and Wannanhua pigs

DNA methylation was one of the earliest discovered epigenetic modifications in vertebrates, and is an important epigenetic mechanism involved in the expression of genes in many biological processes, including muscle growth and development. Its effects on economically important traits are evidenced in reported differences in meat quality traits between Chinese indigenous pig breeds (Wannanhua pig) and Western commercial pig breeds (Yorkshire pig), and this presents a unique model for analyzing the effects of DNA methylation on these traits. In the present study, a whole genome DNA methylation analysis was performed on the two breeds using methylated DNA immunoprecipitation. GO functional enrichment and pathway enrichment analyses identified differentially methylated genes primarily associated with fatty acid metabolism, biological processes of muscle development and signaling pathways related to muscle development and pork quality. Differentially methylated genes were verified by sodium pyrosequencing, and the results were consistent with the sequencing results. The results of the integrative analysis between DNA methylation and gene expression revealed that the DNA methylation levels showed a significantly negative correlation with gene expression levels around the transcription start site of genes. In total, 41 genes were both differentially expressed and methylated; these genes were related to fat metabolism, lipid metabolism and skeletal muscle development. This study could help further explore the molecular mechanisms and phenotypic differences in pig growth and development among different breeds.

DLSR: a solution to the parallax artefact in X-ray diffraction computed tomography data

A new tomographic reconstruction algorithm is presented, termed direct least-squares reconstruction (DLSR), which solves the well known parallax problem in X-ray-scattering-based experiments. The parallax artefact arises from relatively large samples where X-rays, scattered from a scattering angle 2θ, arrive at multiple detector elements. This phenomenon leads to loss of physico-chemical information associated with diffraction peak shape and position (i.e. altering the calculated crystallite size and lattice parameter values, respectively) and is currently the major barrier to investigating samples and devices at the centimetre level (scale-up problem). The accuracy of the DLSR algorithm has been tested against simulated and experimental X-ray diffraction computed tomography data using the TOPAS software.

Cohort protocol: Guangzhou High-Risk Infant Cohort study

INTRODUCTION

Despite the increase in the survival rate of high-risk infants (HRIs) worldwide, the prevalence of motor and neurodevelopmental sequelae in such newborns has not shown concomitant improvement. Meanwhile, there are few cohorts that explore factors related to the development of HRIs in China. Therefore, the Guangzhou High-Risk Infant Cohort (GHRIC) has been designed to examine the complex relationships among a myriad of factors influencing growth and development in such children.

METHODS AND ANALYSIS

The GHRIC study is a prospective cohort study that by the year 2023 will enrol an estimated total of 3000 HRIs from Guangzhou Women and Children's Medical Center (GWCMC) in Guangzhou, China. This study is designed to assess the growth and cognitive characteristics of HRIs and the risk factors affecting their development and prognoses. Data on risk factors, neurodevelopmental and cognitive-function evaluations, laboratory results, and specimens will be collected and analysed. Information on perinatal and clinical interventions for these infants will also be recorded during regular follow-up visits until age 6.

ETHICS AND DISSEMINATION

The protocol for this study has been approved by the Research Ethics Committee of GWCMC, which accepted responsibility for supervising all of the aspects of the study (No. 2017102712). Study outcomes will be disseminated through conference presentations, peer-reviewed publications, the Internet and social media.

TRIAL REGISTRATION NUMBER

ChiCTR-EOC-17013236.

[Research progress of non-alcoholic fatty liver disease in postmenopausal women]

Non-alcoholic fatty liver disease (NAFLD) is a common chronic liver disease with a risk of developing non-alcoholic hepatitis, cirrhosis and liver cancer. Postmenopausal women have an increased risk of developing metabolic diseases including NAFLD under the influence of various factors such as aging, endocrine and metabolic changes. This article summarizes the latest research of NAFLD in postmenopausal women to elaborate and analyze the epidemiological characteristics, correlation between NAFLD and postmenopause, possible pathogenesis as well as feasible prevention and treatment methods.

Hollow Plasma Acceleration Driven by a Relativistic Reflected Hollow Laser

In order to address the present difficulty in experimentally generating the relativistic Laguerre-Gaussian laser, primarily due to damage caused to optical modulators, a high-reflectivity phase mirror is applied in the femtosecond petawatt laser system to generate a relativistic hollow laser at the highest intensity of 6.3×10^{19}  W/cm^{2} for the first time. A simple optical model is used to verify that the vortex laser may be generated in this new scheme; using such a relativistic vortex laser, the hollow plasma drill and acceleration are achieved experimentally and proven by particle-in-cell simulations. With the development of the petawatt laser, this scheme opens up possibilities for the convenient production of the relativistic hollow laser at high repetition and possible hollow plasma acceleration, which is important for a wide range of applications such as the generation of radiation sources with orbital angular momentum, fast ignition for inertial confinement fusion, and jet research in the astrophysical environment.

[The phenotypes and genotypes in 314 patients with isolated methylmalonic acidemia]

Objectives: To summarize the clinical and genetic characteristics of the patients with isolated methylmalonic acidemia and investigate the strategies for the diagnosis, treatment and prevention. Methods: Three hundred and fourteen patients (180 males, 134 females) with isolated methylmalonic acidemia were ascertained from 26 provinces or cities across the mainland of China during January 1998 to March 2020. Genetic analysis was performed by Sanger sequencing, gene panel sequencing, whole exome sequencing, multiplex ligation-dependent probe amplification or quantitative PCR. According to the age of onset, the patients were divided to early-onset group (≤12 months of age) and the late-onset group (>12 months of age). They were treated by cobalamin, L-carnitine and (or) special diet and symptomatic treatment. Statistical analysis was done using Chi-square test. Results: Fifty-eight of 314 (18.5%) patients were detected by Newborn screening using liquid chromatography tandem mass spectrometry. Five cases (1.6%) had a postmortem diagnosis. Two hundred and fifty-one patients (79.9%) were clinically diagnosed with an age of onset ranged from 3 hours after birth to 18 years. One hundred and fifty-nine patients (71.0%) belonged to early-onset groups, 65 patients (29.0%) belonged to the late-onset group. The most common symptoms were metabolic crises, psychomotor retardation, epilepsy, anemia and multiple organ damage. Metabolic acidosis and anemia were more common in early-onset patients than that in late-onset patients (20.8%(33/159) vs. 9.2% (6/65), 34.6% (55/159) vs. 16.9% (11/165), χ(2)=4.261, 6.930, P=0.039, 0.008). Genetic tests were performed for 236 patients (75.2%), 96.2%(227/236) had molecular confirmation. One hundred and twenty-seven variants were identified in seven genes (MMUT, MMAA, MMAB, MMADHC, SUCLG1, SUCLA2, and MCEE), of which 49 were novel. The mut type, caused by the deficiency of methylmalonyl-CoA mutase, was the most common (n=211, 93%) cause of this condition. c.729_730insTT, c.1106G>A and c.914T>C were the three most frequent mutations in MMUT gene. The frequency of c.914T>C in early-onset patients was significantly higher than that in late-onset patients (8.3% (18/216) vs. 1.6% (1/64), χ(2)=3.859, P=0.037). Metabolic crisis was more frequent in mut type than the other types (72.6% (114/157) vs. 3/13, χ(2)=13.729, P=0.001),developmental delay and hypotonia were less frequent in mut type (38.2% (60/157) vs. 9/13, 25.5% (40/157) vs. 8/13, χ(2)=4.789, 7.705, P=0.030, 0.006). Of the 58 patients identified by newborn screening, 44 patients (75.9%) who were treated from asymptomatic phase developed normally whereas 14 patients (24.1%) who received treatment after developing symptoms exhibited varying degrees of psychomotor retardation. Conclusions: The characteristics of phenotypes and genotypes among Chinese patients with isolated methylmalonic acidemia were analyzed. Expanded the mutation spectrum of the associated genes. Because of the complex clinical manifestations and severe early onset of isolated methylmalonic acidemia, Newborn screening is crucial for early diagnosis and improvement of prognosis. MMUT gene is recommended for carrier screening as an effort to move the test earlier as a part of the primary prevention of birth defects.

Behavioural, social and structural-level risk factors for developing AIDS among HIV-positive people who use injection drugs in a Canadian setting, 1996-2017

People who use injection drugs (PWID) experience high rates of HIV acquisition and, as a result of lower rates of optimal access and adherence to combination antiretroviral therapy (ART), experience worse HIV treatment outcomes than other key affected populations. However, the incidence and risk factors for the development of AIDS among HIV-positive PWID have not been completely described. We used data from a community-recruited prospective cohort of HIV-positive PWID in Vancouver, Canada, a setting with universal no-cost ART and a comprehensive clinical monitoring registry. We used multivariable extended Cox models to identify factors associated with time to AIDS. Between 1996 and 2017, 396 participants, including 140 (35.4%) women, were followed for a median of 39.0 months (interquartile range: 16.6-76.2), among whom 165 (41.7%) developed AIDS. In a multivariable model, homelessness (Adjusted Hazard Ratio [AHR] = 1.76 (1.18-2.61)) and injection drug use within the preceding six months (AHR = 1.74 (1.17-2.58)) were independently associated with a higher risk of developing AIDS. Despite widespread scale-up of programmes to improve ART utilization, significant risk factors for the development of AIDS remain among HIV-positive PWID in this setting.