[Prediction of pathological remission of head and neck squamous cell carcinoma patients after neoadjuvant immunochemotherapy and construction of clinical model based on clinical features and inflammatory markers].

Objective: To analyze the potential clinical biological factors influencing the major pathological response (MPR) to neoadjuvant immunochemotherapy in patients with resectable head and neck squamous cell carcinoma (HNSCC). Methods: This retrospective study enrolled patients with resectable HNSCC who underwent neoadjuvant immunochemotherapy at Sun Yat-sen University Cancer Center from June 1, 2019 to December 31, 2021. Binary logistic regression was used to analyze the correlation between clinical characteristics, inflammatory markers and MPR, and a nomogram model was constructed. The calibration curve and decision curve analysis were used to verify the predictive ability and accuracy of the nomogram model. Results: A total of 173 patients were included in the study, with 141 males and 32 females, aged from 22 to 83 years. After pathological assessment, the patients were divided into two groups: MPR group (108 cases) and non MPR group (65 cases). Logistics regression analysis indicated that the patients with HPV+oropharyngeal cancer, partial response or complete response by imaging assessment, low pre-treatment platelet/lymphocyte ratio, low pre-treatment C reactive protein/albumin ratio and lower pre-and post-treatment C reactive protein/albumin ratio difference were more likely to have MPR (all P<0.05). Nomogram model was constructed based on the above factors, with a C-index of 0.826 (95%CI: 0.760-0.892), and the calibration curve and decision curve analysis confirmed the prediction accuracy of the model. Conclusion: This study shows that many factors are related to MPR of patients with resectable HNSCC receiving neoadjuvant immunochemotherapy and the constructed nomogram model helps to develop personalized treatment strategies for the patients.

Clinicopathological characteristics of myelodysplastic syndromes with del(5q) in Taiwan.

BACKGROUND: Myelodysplastic syndromes (MDS) are a group of clonal haematopoietic stem cell disorders characterised by ineffective haematopoiesis and cytopenia. Studies have reported differences in MDS between Asian and Western countries, but data from Taiwan are scarce. MATERIALS AND METHODS: In this study we analysed the clinical and pathological features of 32 Taiwanese MDS patients with del(5q) (ie, del(5q) alone [Group A, n = 11], del(5q) with one additional cytogenetic abnormality other than monosomy 7 or del(7q) [Group B, del(5q)+1; n = 6], and del(5q) with ≥2 additional cytogenetic abnormalities [Group C, n = 15]). RESULTS: Progression-free survival (PFS) and overall survival (OS) were more favourable for Group A than for Groups B (p < 0.05) and C (p ≤ 0.001). Multivariate analysis showed that age >70 years, thrombocytopenia, and karyotype other than del(5q) alone were poor prognostic factors. Among the patients that had World Health Organization (WHO)-defined MDS with isolated del(5q), one patient (9%) had a typical marrow morphology of 5q minus syndrome with erythroid hypoplasia and four patients (36%) had hypolobated megakaryocytes. In addition, PFS and OS were significantly more favorable for the patients with del(5q) alone than for those with del(5q)+1 (p < 0.05). CONCLUSION: The bone marrow morphology, clinical features, and prognosis of Taiwanese MDS patients with del(5q) were different from those associated with MDS with isolated del(5q) as defined in the current WHO classification. Researchers should compare different geographic regions and racial populations to determine whether geographic and racial differences exist with respect to MDS with del(5q).

Relationship between body mass index and pulse pressure in a non-diabetic population: evidence from a multicenter, cross-sectional study.

OBJECTIVE: Growing evidence shows that pulse pressure (PP) is a strong risk factor for cardiovascular disease and is closely associated with cardiovascular events, strokes, and mortality. However, currently, data on the relationship between body mass index (BMI) and PP are still limited. SUBJECTS AND METHODS: Here, a cross-sectional study was conducted based on 211,809 non-diabetic adults in 11 cities in China from 2010 to 2016. Raw data were obtained from a public database (www.datadryad.org). According to the BMI level, they are classified into "underweight", "normal", "overweight", and "obesity" groups. Two groups of continuous variables were measured by the Mann-Whitney test, while the differences between multiple groups were tested by Kruskal-Wallis' One-Way ANOVA and Dunn's test. Besides, multiple linear regression analyses were performed to assess the linear relationship between BMI and PP. In addition, multivariate logistic regression was carried out to further confirm the relationship between different BMI levels and the prevalence of high PP. RESULTS: In the total population, BMI was linearly positively related to PP regardless of gender and age, but it was not observed in the elevated blood pressure group. Multiple linear regression analysis showed that after fully adjusting for the maximum covariates, compared to the normal group, PP in the overall population decreased by 2.19 mmHg in the underweight group and increased by 1.426 and 2.919 mmHg in the overweight and obese groups, respectively. Similar results were observed in men, women, age <60 years, and normotensive groups. However, there was no significantly linear relationship between BMI and PP at the age of ≥60 years and elevated blood pressure groups. Besides, from multiple logistic regression analysis, the similar results were obtained, with no obvious association between BMI and high PP prevalence in those aged ≥60 years or with elevated blood pressure. CONCLUSIONS: PP increased with rising BMI in the overall population. However, stratified analysis demonstrated no significant association between BMI and PP in individuals aged over 60 years or with elevated blood pressure.

Ambient air pollution exposure and telomere length: a systematic review and meta-analysis.

OBJECTIVE: This study aimed to provide evidence of the associations between pre- and post-birth and adulthood air pollution exposure with telomere length. STUDY DESIGN: The databases of PubMed, Embase, and Web of Science were searched up to June 1st, 2022 in order to include relevant observational studies and perform a systematic review and meta-analysis. METHODS: The random-effects meta-analysis was grouped by air pollutant and exposure window (pre- and post-birth and adulthood) to evaluate the summary effect estimate. Cochran's Q and I2 statistics were used to evaluate the heterogeneity among the included studies. The quality of individual studies was evaluated using the national toxicology program/office of health assessment and translation risk of bias rating tool. RESULTS: We identified 18 studies, covering 8506 children and 2263 adults from multiple countries. We found moderate evidence that particulate matter less than 2.5 µm (PM2.5) exposure during the entire pregnancy (-0.043, 95% CI: -0.067, -0.018), nitrogen dioxide (NO2) exposure during the first trimester (-0.016, 95% confidence interval [CI]: -0.027, -0.005), long-term adulthood PM2.5 exposure were associated with shortening telomere length. Mild to high between-study heterogeneity was observed for the most tested air pollutant-telomere length combinations in different exposure windows. CONCLUSIONS: This systematic review and meta-analysis provides the evidence which strongly supports that prenatal PM2.5 and NO2 exposures were related to reduced telomere length, while prenatal sulfur dioxide (SO2) and carbon monoxide (CO) exposures, childhood PM2.5, particulate matter less than 10 µm (PM10), NO2 exposures and short-term adulthood PM2.5 and PM10 exposures were not associated with telomere length. Further high-quality studies are needed to elaborate our suggestive associations.

[Risk factor assessment and adverse outcome prediction of placenta accreta in pregnant women after cesarean section complicated with placenta previa: a national multicenter retrospective study].

Objective: To study the risk factors of adverse pregnancy outcomes for the diagnosis and treatment of pregnancy after cesarean section complicated with placenta previa. Methods: A national multicenter retrospective study was conducted to select a total of 747 pregnant women with the third trimester singleton pregnancy after cesarean section complicated with placenta previa from 12 tertiary hospitals in January 1st to December 31st, 2018. The risk factors of severe adverse outcomes [hysterectomy, intraoperative blood loss ≥1 000 ml, intraoperative diagnosis of placenta accreta spectrum disorders (PAS)] in pregnant women with second pregnancy complicated with placenta previa after cesarean section were investigated by logistic regression analysis. The roles of prenatal ultrasonography and magnetic resonance imaging (MRI) in the prediction of PAS and severe adverse outcomes were observed. According to whether vascular intervention was performed (uterine artery embolization or abdominal aortic balloon occlusion), the pregnant women were divided into the blocked group and the unblocked group, and the maternal and infant perinatal outcomes between the two groups were compared. Results: (1) General information: the hysterectomy rate of 747 pregnant women with second pregnancy complicated with placenta previa after cesarean section was 10.4% (78/747), the intraoperative blood loss ≥1 000 ml in 55.8% (417/747), and PAS was confirmed in 47.5% (355/747). The incidence of uterine rupture was 0.8% (6/747). (2) Analysis of risk factors for severe adverse outcomes: based on binary unconditioned logistic regression univariate and multivariate analysis, the risk factors for hysterectomy were the mode of vascular embolization and intraoperative blood loss. The probability of hysterectomy with uterine artery embolization was 5.319 times higher than that with abdominal aortic balloon occlusion (95%CI: 1.346-21.018). The risk factors of intraoperative blood loss ≥1 000 ml were the number of cesarean section delivery, ultrasonography indicated PAS and suspected PAS, intraoperative PAS and complete placenta previa. The risk factors for intraoperative PAS were uterine scar thickness, ultrasonography indicated PAS and suspected PAS, MRI indicated PAS and suspected PAS, and complete placenta previa. (3) The roles of ultrasonography and MRI in predicting PAS: the sensitivity and specificity of ultrasonography in predicting PAS were 47.5% and 88.4%; the kappa value was 0.279 (P<0.001), with fair agreement. The sensitivity and specificity of MRI to predict PAS were 79.2% and 97.8%, respectively. The kappa value was 0.702 (P<0.001), indicating a good agreement. The intraoperative blood loss and hysterectomy rate of pregnant women with PAS indicated by ultrasonography and MRI were significantly higher than those with PAS only by ultrasonography or MRI. (4) Influence of vascular occlusion on pregnancy outcome: there were no significant differences in intraoperative blood loss and incidence of intraoperative bleeding ≥1 000 ml between the blocked group and the unblocked group (all P>0.05). There was no significant difference in intraoperative blood loss between the pregnant women with abdominal aortic balloon occlusion, uterine artery embolization and those without occlusion (P=0.409). The hysterectomy rate of pregnant women with uterine artery embolization was significantly higher than those with abdominal aortic balloon occlusion [39.3% (22/56) vs 10.0% (5/50), P=0.001]. Conclusions: In the third trimester of pregnancy with placenta previa after cesarean section, MRI examination has better consistency in predicting PAS than ultrasonography examination. Ultrasonography examination combined with MRI examination could effectively predict the hysterectomy rate and intraoperative blood loss. Vascular occlusion could not reduce the amount of intraoperative blood loss. The hysterectomy rate of pregnant women with uterine artery embolization is higher than those with abdominal aortic balloon occlusion.

The effect of cold exposure on the levels of glucocorticoids, 11-hydroxysteroid dehydrogenase 2, and placental vascularization in a rat model.

OBJECTIVE: Cold exposure (CE) before birth is one of the initial stressors that may impact mammalian pregnancy, changing placental and fetal development and affecting the health of the offspring. While glucocorticoids (GCs) participate in the body's response to the stress of CE, the specific mechanisms of their action are unclear. This study aims to determine the effect of CE stress on the placenta and to test whether stress, caused by cold exposure in pregnancy impairs fetal development by changing placental angiogenesis via excessive GC expression. MATERIALS AND METHODS: CE rat model was created by exposing 30 SD rats to cold preconception, or during the first, second, and third weeks of pregnancy. Serum cortisol and soluble fms-like tyrosine kinase-1 (sFlt-1) expression levels, physiological index changes (food intake, body weight change and blood pressure), and pregnancy outcomes (fetal rat weight, number of live fetal rats, and placental weight) were collected at baseline and at different time points after the conception. Protein expression levels of 11 ß-hydroxysteroid dehydrogenase 2 (11ß-HSD2), glucocorticoid receptor, vascular endothelial growth factor A (VEGF-A), placental growth factor (PIGF), and sFlt-1 in placental tissues were measured by western blotting. Cytokeratin (CK) and laminin (LN) in trophoblasts, and α-actin in vascular smooth muscle of the spiral arteries of pregnant rats after the systemic cold treatment were assessed by immunofluorescence and visualized by fluorescent microscopy. To test the effect of 11ß-HSD2 levels on the placental recasting, human first-trimester extravillous trophoblast cells (HTR8/SVneo) underwent knockdown using specific 11ß-HSD2 siRNA constructs.  Expression levels of 11ß-HSD2 were analyzed by quantitative real-time PCR (qPCR) and into HTR8 cells, and the expression levels of the 11ß-HSD2 gene in each group were measured using qPCR. Cell migration and invasion was assessed by Transwell migration assay, and sFlt-1 levels in HTR8 cells were measured by ELISA. RESULTS: CE pre-conception led to consistently increasing serum corticosterone and sFlt-1 levels throughout pregnancy, and persistently increased diastolic blood pressure (DBP) in rat CE model compared to control animals. CE during the second week of gestation (Gp.3) was associated with significantly lower placental weight (p=0.0003). Cold exposure in the third week (Gp.4) was associated with significantly (p=0.001) lower fetal weight. CE pre-conception was associated with significantly decreased placental levels of 11ß-HSD2, glucocorticoid receptor, VEGF-A, PIGF, and sFlt-1 proteins and α-actin compared to the control group. Silencing 11ß-HSD2 by siRNA led to reduced cell migrations and invasion, and markedly increased expression levels of sFlt-1 in HTR8/SVneo cells (p<0.05). CONCLUSIONS: Pre-conception cold exposure and during early pregnancy leads to increased GCs levels and impaired placental 11ß-HSD2 activity. We suggest that the subsequent 11ß-HSD2-induced increase in the sFlt-1expression during early pregnancy may affect placental vascular remodeling and change placental morphological structure and function.

Cannabidiol counters the effects of a dominant-negative pathogenic Kv7.2 variant.

Epilepsy and neurodevelopmental disorders can arise from pathogenic variants of KCNQ (Kv7) channels. A patient with developmental and epileptic encephalopathy exhibited an in-frame deletion of histidine 260 on Kv7.2. Coexpression of Kv7.2 mutant (mut) subunits with Kv7.3 invoked a decrease in current density, a depolarizing shift in voltage for activation, and a decrease in membrane conductance. Biotinylation revealed an increased level of surface Kv7.2mut compared to Kv7.3 with no change in total membrane protein expression. Super-resolution and FRET imaging confirmed heteromeric channel formation and a higher expression density of Kv7.2mut. Cannabidiol (1 µM) offset the effects of Kv7.2mut by inducing a hyperpolarizing shift in voltage for activation independent of CB1 or CB2 receptors. These data reveal that the ability for cannabidiol to reduce the effects of a pathogenic Kv7.2 variant supports its use as a potential therapeutic to reduce seizure activity.

Effect of induction of labor on maternal and perinatal outcomes in low-risk singleton pregnancies: a retrospective case-control study.

OBJECTIVE: The aim of the study was to investigate the effect of induction of labor on maternal and fetal outcomes. PATIENTS AND METHODS: This retrospective case-control study included 4386 pregnant women with low-risk singleton pregnancies who underwent regular prenatal examination and successful vaginal delivery at ≥41 weeks and 0 days of gestation in Fujian Maternal and Child Health Hospital between January 2014 and December 2018. Clinical data of women were retrospectively divided into the induction of labor group (2007 cases) and spontaneous onset of labor group (2361 cases) based on the mode of labor initiation. Two-sample independent t-test and χ2 tests were used to analyze the differences in clinical characteristics, such as maternal age and parity between the two groups. RESULTS: The induction of the labor group had a significantly longer total duration of labor (9.37±5.37 vs. 8.82±5.13 h; p<0.001), more postpartum blood loss (219.18±188.32 vs. 199.95±124.69 mL; p=0.01) and a significantly higher incidence of severe postpartum hemorrhage (PPH) comparing to the spontaneous onset of labor group [0.8% (16/2007) vs. 0.33% (8/2361); p=0.041]. However, no significant difference was found in the neonatal outcomes. After adjusting for age, induction of labor in nulliparous women was more likely to lead to PPH than the spontaneous onset of labor [2.74% (55/2007) vs. 1.65% (39/2361); odds ratio=1.557; 95% confidence interval: 1.039-2.332; p<0.05]. CONCLUSIONS: Induction of labor increases the duration of labor and postpartum blood loss, especially in primary parturient, leading to an increased risk of PPH. This increase may be related to the overall higher duration of labor, associated with IOL. Therefore, low-risk nulliparous women should try to avoid induction of labor without medical indications.

[The clinical value of oral robotic surgery in the treatment of oropharyngeal squamous cell carcinoma].

Objective: To explore the therapeutic effects of transoral robotic surgery (TORS) and traditional surgical modes in oropharyngeal squamous cell carcinoma (OPSCC). Methods: The clinicopathological data of patients with oropharyngeal squamous cell carcinoma treated at Sun Yat-sen University Cancer Center from 2010 to 2018 were retrospectively analyzed. 135 cases were treated with traditional surgery (non-TORS group), while 52 cases were treated with TORS (TORS group). The prognosis of the two groups of patients were analyzed by Kaplan-Meier method and Log rank test, the influencing factors were analyzed by Cox regression model. Results: The 2-year overall survival (OS, 94.2%) and 2-year progression-free survival (PFS, 93.8%) of patients in the TORS group were better than those in the non-TORS group (71.4% and 71.4%, respectively, P<0.05). The 2-year OS (93.3%) and 2-year PFS (92.8%) of TORS group patients in T1-2 stage were better than those of non-TORS group (73.1% and 72.8%, respectively, P<0.05). The 2-year OS (95.8%) and 2-year PFS (95.2%) of patients with stage Ⅰ to Ⅱ in the TORS group were not significantly different from those in the non-TORS group (84.1% and 83.9%, respectively, P>0.05). The 2-year OS (92.9%) and 2-year PFS rate (92.7%) of patients with stage Ⅲ to Ⅳ in the TORS group were better than those in the non-TORS group (64.7% and 63.9%, respectively, P<0.05). The 2-year OS (94.4%) of HPV-positive patients in the TORS group was not significantly different from that in the non-TORS group (83.3%, P=0.222). The 2-year OS of HPV-negative patients in the TORS group (94.1%) was significantly different from that in the non-TORS group (43.7%, P<0.001). HPV status was an independent prognostic factor (P=0.008). Conclusions: TORS has a better prognosis in the treatment of oropharyngeal squamous cell carcinoma compared with the traditional treatment methods. The patients with T1-T2 can achieve better survival benefits after TORS treatment. The HPV-positive OPSCC patients has a better prognosis than that of HPV-negative OPSCC patients, and regardless of HPV status, OPSCC patients in the TORS group could obtain a better survival prognosis.

[Application of transoral robotic surgery in treatment of oropharyngeal squamous cell carcinoma].

Objective: To evaluate the therapeutic and prognostic outcomes of transoral robotic surgery (TORS) for oropharyngeal squamous cell carcinoma (OSCC). Methods: A retrospective study of 99 OSCC patients treated with TORS in Department of Head and Neck Surgery, Sun Yat-sen University Cancer Center between April 2017 and May 2021 was conducted. There were 84 males and 15 females, with an age range of 35-85 years. Patients' clinical characteristics, including clinical staging, HPV infection status, perioperative management and postoperative adjuvant treatment, were recorded. The overall survival (OS) and progression-free survival (PFS) were analyzed. The survival outcomes were analyzed with Kaplan-Meier method and Log-rank test. Results: The hospital stay of OSCC patients with TORS was (5.3±2.9) days and the average time of postoperative nasal feeding tube indwelling was (15.2±10.8) days. Among the 99 patients, 21 (21.2%) received tracheotomy and the average time of tracheotomy tube indwelling was (11.9±11.4) days. The two-year OS and PFS in patients with follow-up over two years were 94.0% and 87.7%, respectively and the three-year OS and PFS of patients with follow-up over three years were 94.0% and 78.9%, respectively. The two-year OS and PFS were respectively 97.4% and 88.9%, for patients with stages I-II and 86.8% and 88.9% for patients with stages III-IV. HPV-negative and HPV-positive patients had respectively two-year OS (100.0% vs. 91.5%) and PFS (88.9% vs. 87.2%). There was no significantly statistical difference in survival between patients with and without adjuvant radiotherapy after TORS (82.6% vs. 90.5%, HR=0.52, 95%CI: 0.12-2.23, P=0.400). Conclusions: TORS is more suitable for the treatment of patients with early (Ⅰ-Ⅱ) or HPV-positive oropharyngeal squamous cell carcinoma, and the recovery after TORS treatment is good.

ToTEM: A software for fast TEM image simulation.

ToTEM, a multislice-based image simulation software is developed for transmission electron microscope (TEM). This software implements the following major features: (i) capability of assigning three-dimensional potentials of atom into multiple slices and precise introduction of phase shift caused by the sub-pixel atomic position, (ii) employing CUDA coding and graphical processing units (GPU) with multithreading parallel algorithm based on the powerful batch (inverse) fast Fourier transform (FFT), which is especially beneficial for image simulation of scanning transmission electron microscopy (STEM) or (integrated) differential phase contrast (I)DPC, (iii) design for efficiently generating large batch of data set of high-resolution transmission electron microscopy (HRTEM) images. Image simulation acceleration for STEM has been verified by simulating a large-scale SrTiO3 . Additionally, iDPC image of MFI-type zeolites with xylene molecules encapsulated in straight channels demonstrates the advantage of iDPC in detecting light molecules.

[Retropharyngeal lymph node dissection in head and neck cancers treated with transoral robotic surgery].

Objective: To evaluate the indications, safety, feasibility, and surgical technique for patients with head and neck cancers undergoing transoral robotic retropharyngeal lymph node (RPLN) dissection. Methods: The current study enrolled 12 consecutive head and neck cancer patients (seven males and four females) who underwent transoral robotic RPLN dissection with the da Vinci surgical robotic system at the Sun Yat-sen University Cancer Center from May 2019 to July 2020. Seven patients were diagnosed as nasopharyngeal carcinoma with RPLN metastasis after initial treatments, 4 patients were diagnosed as thyroid carcinoma with RPLN metastasis after initial treatments, and one patient was diagnosed as oropharyngeal carcinoma with RPLN metastasis before initial treatments. The operation procedure and duration time, intraoperative blood loss volume and complications, nasogastric feeding tube dependence, tracheostomy dependence, postoperative complications, and hospitalization time were recorded and analyzed. Results: All patients were successfully treated by transoral robotic dissection of the metastatic RPLNs, none of which was converted to open surgery. RPLNs were completely resected in 10 patients, and partly resected in 2 patients (both were nasopharyngeal carcinoma patients). The mean number of RPLN dissected was 1.7. The operation duration time and intraoperative blood loss volume were (191.3±101.1) min and (150.0±86.6) ml, respectively. There was no severe intraoperative complication such as massive haemorrhage or adjacent organ injury during surgery. Nasogastric tube use was required in all patients with (17.1±10.6) days of dependence, while tracheotomy was performed in 8 patients with (11.6±10.7) days of dependence. The postoperative hospitalization stay was (8.5±5.7) days. Postoperative complications occurred in 4 patients, including 2 of retropharyngeal incision and 2 of dysphagia. During a follow-up of (6.5±5.1) months, disease-free progression was observed in all patients, 10 patients were disease-free survival and other 2 patients were survival with tumor burden. Conclusions: The transoral robotic RPLN dissection is safety and feasible. Compared with the traditional open surgical approach, it is less traumatic and safer, has fewer complications and good clinical application potentiality. The indications for transoral robotic RPLN dissection include thyroid carcinoma, oropharyngeal carcinoma, and some selected nasopharyngeal carcinoma and other head and neck cancers. Metastatic RPLNs from some nasopharyngeal carcinoma with incomplete capsule, unclear border and adhesion to the surrounding vessels are not suitable for transoral robotic RPLN dissection.

[Course of disease and related epidemiological parameters of COVID-19: a prospective study based on contact tracing cohort].

Objective: To analyze the course of disease and epidemiological parameters of COVID-19 and provide evidence for making prevention and control strategies. Methods: To display the distribution of course of disease of the infectors who had close contacts with COVID-19 cases from January 1 to March 15, 2020 in Guangdong Provincial, the models of Lognormal, Weibull and gamma distribution were applied. A descriptive analysis was conducted on the basic characteristics and epidemiological parameters of course of disease. Results: In total, 515 of 11 580 close contacts were infected, with an attack rate about 4.4%, including 449 confirmed cases and 66 asymptomatic cases. Lognormal distribution was fitting best for latent period, incubation period, pre-symptomatic infection period of confirmed cases and infection period of asymptomatic cases; Gamma distribution was fitting best for infectious period and clinical symptom period of confirmed cases; Weibull distribution was fitting best for latent period of asymptomatic cases. The latent period, incubation period, pre-symptomatic infection period, infectious period and clinical symptoms period of confirmed cases were 4.50 (95%CI:3.86-5.13) days, 5.12 (95%CI:4.63-5.62) days, 0.87 (95%CI:0.67-1.07) days, 11.89 (95%CI:9.81-13.98) days and 22.00 (95%CI:21.24-22.77) days, respectively. The latent period and infectious period of asymptomatic cases were 8.88 (95%CI:6.89-10.86) days and 6.18 (95%CI:1.89-10.47) days, respectively. Conclusion: The estimated course of COVID-19 and related epidemiological parameters are similar to the existing data.

Merkel cell carcinoma in Taiwan: A rare tumour with a better prognosis in those harbouring Merkel cell polyomavirus.

Merkel cell carcinoma (MCC) is a rare malignant cutaneous neuroendocrine tumour affecting mainly elderly patients and is more common in the West than in Asia. It is associated with Merkel cell polyomavirus (MCPyV), immunosuppression, and ultraviolet light. In this study, we retrospectively investigated the first series of MCC from Taiwan and identified 19 cases from three tertiary centres. All patients were males with a median age of 67.5. Twelve (63%) cases occurred in the extremities, with one unique case presenting initially as nodal metastasis of unknown primary. Immunohistochemically, the great majority of tumours expressed CK20 (89%), synaptophysin (89%), and INSM1 (84%), with none positive for TTF1. Eleven (58%) cases were positive for MCPyV by immunohistochemistry (clone CM2B4). All patients were treated with excision, including four with additional radiotherapy and one with radiotherapy and chemotherapy. Nodal status and treatment modalities significantly affected survival. The median survival time of MCPyV-positive cases was much longer than the negative cases (median 40 vs. 10 months). In summary, we presented the first report on the clinicopathological features of MCC in Taiwan, with 58% cases associated with MCPyV. The prognosis of patients with MCPyV-positive tumours was better than those negative for MCPyV.

[Induction of peripheral blood mononuclear cells to hepatocyte-like cells and preliminary study of cell response to injury under the effect of acetaminophen].

Objective: To establish a method for the induction of peripheral blood mononuclear cells to hepatocyte-like cells, and preliminarily investigate cell response to injury under the effect of acetaminophen (APAP). Methods: The surface marker CD45 of peripheral blood mononuclear cells wase detected cells by using flow cytometry and immunofluorescence methods. The cellular morphology of induced hepatocyte-like cells was observed under an inverted microscope. Real-time fluorescent quantitative PCR (RT-PCR) was used to detect the expression level of hepatocyte-specific genes, such as cytochrome (CY) P1A2, CYP3A4, CYP2C9, albumin (ALB), alpha-fetoprotein (AFP), and hepatocyte nuclear factor (HNF)4α mRNA. Immunofluorescence method was used to detect intracellular hepatocyte markers AFP, HNF4α, and ALB expression at the protein level. Biochemical analyzer was used to detect hepatocyte-specific secretory functions of AFP, ALB, and urea. Luciferase chemiluminescence method was used to detect the activity of key drug metabolizing enzyme CYP3A4. Colorimetric assay was used to detect the effect of the drug acetaminophen on hepatocyte-like cells, and alanine aminotransferase (ALT) was used as an indicator of liver cell injury. The statistical differences between the data were compared with t-test and rank-sum test. Results: The positive expression rate of CD45 cell surface markers isolated from peripheral blood mononuclear cells was about 98%, and hepatocyte-like cell morphology changes appeared on 15th day of induction. Compared with isolated mononuclear cells, CYP1A2, CYP3A4, CYP2C9, ALB, AFP and HNF4α mRNA was markedly elevated. The expression level of AFP, ALB and HNF4α protein were equally increased, and the secretory function of AFP, ALB and urea were enhanced. Compared with primary hepatocytes, CYP1A2, CYP2C9, AFP, HNF4α mRNA, and CYP3A4 mRNA did not decrease. The expression levels of AFP, ALB, and HNF4α proteins in the cells did not decrease, and the secretory function of AFP, ALB, and urea did not decrease. In addition, the CYP3A4 enzyme activity produced by hepatocyte-like cells was similar to that of primary hepatocytes. Compared with hepatocyte-like cells incubated without APAP, hepatocyte-like cells incubated with APAP had higher ALT level. Under the effect of APAP, the ALT level of hepatocyte-like cells was higher than isolated mononuclear cells. Conclusion: Peripheral blood mononuclear cells can be induced into hepatocyte-like cells with partial characteristics of hepatocytes, including the activity of CYP3A4, a key enzyme of hepatocyte drug metabolism. Additionally, preliminarily ALT secretory features reflect the hepatocytes injury under the effect of acetaminophen.

[Evaluation of the diagnosis and treatment of cesarean scar pregnancy induced in the second trimester: a national multicenter retrospective study].

Objective: To study the risk factors of adverse pregnancy outcomes for induced abortion of cesarean scar pregnancy in midtrimester. Methods: A national multicenter retrospective study was conducted. A total of 154 singletons pregnant women with cesarean scar pregnancy during the second trimester induced abortion by various reasons in 12 tertiary A hospitals were selected, their pregnant outcomes were observed and the risk factors of serious adverse outcomes were analyzed with univariate and multivariate logstic regression; the role of ultrasound and MRI in predicting placenta accreta and severe adverse outcomes was evaluated, the effectiveness of uterine artery embolization (UAE) in preventing hemorrhage in pregnant women with and without placenta accreta was compared. Results: Among 154 subjects, the rate of placenta accreta was 42.2% (65/154), the rate of postpartum hemorrhage≥1 000 ml was 39.0% (60/154), the rate of hysterectomy was 14.9% (23/154), the rate of uterine rupture was 0.6% (1/154). The risk factor of postpartum hemorrhage≥1 000 ml and hysterectomy was placenta accreta (P<0.01). For each increase in the number of parity, the risk of placenta accreta increased 2.385 times (95%CI: 1.046-5.439; P=0.039); and the risk of placenta accreta decreased with increasing ultrasound measurement of scar myometrium thickness (OR=0.033, 95%CI: 0.001-0.762; P=0.033). The amount of postpartum hemorrhage and hysterectomy rate in the group with placenta accreta diagnosed by ultrasound combined with MRI were not significantly different from those in the group with placenta accreta diagnosed by ultrasound only or MRI only (all P>0.05). For pregnant women with placenta accreta, there were no significant difference in the amount of bleeding and hysterectomy rate between the UAE group [median: 1 300 ml; 34% (16/47)] and the non-embolization group (all P>0.05); in pregnant women without placenta accreta, the amount of bleeding in the UAE group was lower than that in the non-embolization group (median: 100 vs 600 ml; P<0.01), but there was no significant difference in hysterectomy rate [2% (1/56) vs 9% (3/33); P>0.05]. Conclusions: (1) Placenta accreta is the only risk factor of postpartum hemorrhage≥1 000 ml with hysterectomy for induced abortion of cesarean scar pregnancy in midtrimester; multi-parity and ultrasound measurement of scar myometrium thickness are risk factors for placenta accreta. (2) The technique of using ultrasound and MRI in predicting placenta accreta of cesarean scar pregnancy needs to be improved. (3) It is necessary to discuss of UAE in preventing postpartum hemorrhage for induced abortion of cesarean scar pregnancy in midtrimester.

[Transoral robotic surgery for parapharyngeal space neoplasm: a report of 7 cases].

Objective: To evaluate the safety, efficacy and feasibility of transoral robotic surgery (TORS) for parapharyngeal space (PPS) neoplasms. Methods: We collected data from 7 patients with PPS neoplasm who received TORS in Sun Yat-sen University Cancer Center between May 2017 and November 2020, and patients' clinical and pathological characteristics were analysed. There were 2 men and 5 women with age ranged from 35 to 76 years. Among them, 2 patients underwent secondary surgery, 2 patients required combined transcervical approach to complete surgery, and 1 patient was suspected of ipsilateral cervical lymph node metastasis and scheduled for diagnostic TORS. The preoperative tumor size, operation time, intraoperative blood loss, postoperative bleeding, dyspnea, neurological impairment, feeding time and postoperative hospital stay were analyzed. SPSS 24.0 was used to analyze the data. Results: TORS was performed successfully with complete removal of tumors in all 7 cases. Among 6 patients with curative TORS, 5 patients received TORS with postoperative diagnoses of neurogenic tumors and 1 patient underwent TORS combined transcervical approach with postoperative disgnosis of recurrent pleomorphic adenoma; no intraoperative tumor rupture occurred; the intraoperative blood loss was 20-200 ml with a median of 40 ml; the operation time was 65.0-238.0 min with a median of 77.5 min; the oral feeding time was 3-6 days with a median of 3 days; and the postoperative hospital stay was 4.2±1.6 days. One patient presented with neck swelling 3 days after surgery, but this symptom relieved 3 days later after treatments with antibiotic, hemostasis and detumescence. One patient received diagnostic TORS, as intraoperative pathology indicating a recurrent pleomorphic adenoma, then the neoplasm got completely resected through transcervical-transparotid approach. None of 7 patients manifested with airway obstruction, bleeding or nerve injury symptoms after operation. All patients were followed for 2 to 44 months, no local recurrence or distant metastasis was found. Conclusions: TORS is a safe, effective and feasible treatment for selected PPS neoplasms, with less cosmetic impact, less trauma and blood loss, few postoperative complications, enhanced postoperative recovery and short hospital stay.

[Research progress of conversion therapy in colorectal cancer liver metastases].

The probability of developing liver metastases in patients with colorectal cancer is 40%-50%. Liver metastases remain an important adverse factor affecting long-term prognosis of colorectal cancer patients. Surgical resection of liver metastases is the only potentially curative treatment option. After comprehensive treatment, initially unresectable liver metastases might be converted to resectable tumors. This concept is known as conversion therapy. In this review, research status of conversion therapy in colorectal cancer liver metastases was summarized, providing updated concept of resectability, discussions on the assessment of tumor response and timing of operation, debates on the influence on tumor sidedness, and latest advancement in the treatment strategy of conversion therapy. Through analyzing existing problems, we hope to offer insights into possible progress in the future and provide references for the development of clinical practice.

Frequent loss of CD10 expression in follicular lymphoma with leukaemic presentation.

INTRODUCTION: Follicular lymphoma (FL) is usually a nodal lymphoma expressing CD10, rarely with leukaemic presentation (FL-LP). MATERIALS AND METHODS: We searched for FL-LP in our institution from 2000 to 2018 and characterised the neoplastic cells by flow cytometry, immunohistochemistry and fluorescence in situ hybridization. Thirteen (6.1%) of 212 FL cases were FL-LP, all de novo neoplasms. The leukaemic cells were small in 12 cases and large in one. All had concurrent FL, mostly (92%; 12/13) low-grade. The single case with large leukaemic cells had a concurrent primary splenic low-grade FL and a double-hit large B-cell lymphoma in the marrow. RESULTS: CD10 was expressed in the leukaemic cells in 38% (5/13) cases by flow cytometry and in 77% (10/13) cases in tumours (p= 0.0471). IGH/BCL2 reciprocal translocation was identified in 85% (11/13) cases. Most patients were treated with chemotherapy. In a median follow-up time of 36 months, nine patients were in complete remission. The 2- and 5-year survival rates were at 100% and 83%, respectively. In this study, we characterised a series of de novo FL-LP in Taiwan. All patients had concurrent nodal and/or tissue tumours, which might suggest that these patients seek medical help too late. CONCLUSION: The lower CD10 expression rate by flow cytometry than by immunohistochemistry might be due to different epitopes for these assays. Alternatively, loss of CD10 expression might play a role in the pathogenesis of leukaemic change. The clinical course of FL-LP could be aggressive, but a significant proportion of the patients obtained complete remission with chemotherapy.

Research Progress of Metabolomics in Forensic Pathology.

ABSTRACT: Metabolomics is an interdisciplinary subject that rose in the post-genomic era, which focuses on quantitative study of the response of living organisms to outside stimulation and pathophysiological changes, as well as multiple dynamic response of the level of in vivo metabolites caused by genetic mutation. It is extensively used in basic research of system biology, materia medica, clinical medicine, etc. In the forensic field, metabolomics mainly focuses on forensic toxicology, but with the generalization of certain techniques, it's foreseeable that metabolomics has a broad research prospect in forensic pathology. This article summarizes the major analysis techniques and methods of metabolomics, describes the research status of metabolomic techniques in the field of forensic pathology application research, including postmortem interval and death cause. Moreover, this article summarizes and discusses the potential applicable areas, in order to provide reference for relative research and application.