Reproducibility of T1ρ and T2 quantification in a multi-vendor multi-site study

OBJECTIVE

To evaluate the multi-vendor multi-site reproducibility of two-dimensional (2D) multi-echo spin-echo (MESE) T2 mapping (product sequences); and to evaluate the longitudinal reproducibility of three-dimensional (3D) magnetization-prepared angle-modulated partitioned k-space spoiled gradient echo snapshots (MAPSS) T1ρ and T2 mapping (research sequences), and 2D MESE T2 mapping, separated by 6 months, in a multi-vendor multi-site setting.

METHODS

Phantoms and volunteers (n = 5 from each site, n = 20 in total) were scanned on four 3 T magnetic resonance (MR) systems from four sites and three vendors (Siemens, General Electric, and Phillips). Two traveling volunteers (3 knees) scanned at all 4 sites at baseline and 6-month follow-up. Data was transferred to one site for centralized processing. Coefficients of variation (CVs) were calculated to evaluate reproducibility.

RESULTS

For baseline 2D MESE T2 measures, average CV were 0.37-2.45% (intra-site) and 5.96% (inter-site) for phantoms, and 3.15-8.49% (intra-site) and 14.16% (inter-site) for volunteers. For longitudinal phantom data, intra-site CVs were 1.42-3.48% for 3D MAPSS T1ρ, 1.77-3.56% for 3D MAPSS T2, and 1.02-2.54% for 2D MESE T2. For the longitudinal volunteer data, the intra-site CVs were 2.60-4.86% for 3D MAPSS T1ρ, 3.33-7.25% for 3D MAPSS T2, and 3.11-8.77% for 2D MESE T2.

CONCLUSION

This study demonstrated excellent intra-site reproducibility of 2D MESE T2 imaging, while its inter-site variation was slightly higher than 3D MAPSS T2 imaging (10.06% as previously reported). This study also showed excellent reproducibility of longitudinal T1ρ and T2 cartilage quantification, in a multi-vendor multi-site setting for both product 2D MESE T2 and 3D MAPSS T1p/T2 research sequences.

Autoinduction Expression Modules for Regulating Gene Expression in Bacillus subtilis

Although quorum sensing (QS) promoters that can autonomously activate gene expression have been identified and engineered in Bacillus subtilis, researchers focus on quantifying individual promoters while ignoring the interaction between other genetic regulatory elements. Here, we constructed the autoinduction expression modules consisting of promoters responsive to QS ComQXPA, ribosome binding sites (RBSs), and terminators. Using superfolder green fluorescent protein (sfGFP) as a reporter gene, three individual element libraries were generated from 945 promoters, 12,000 RBSs, and 425 terminators by random mutation, de novo design, and database mining strategies, respectively. Then, the efficiency of three libraries in regulating gene expression was further enhanced by engineering the core region of each optimal element. After hybridizing the element libraries, the generated expression modules exhibited a 627-fold range in regulating gene expression without significantly affecting the autoinduction initiation. Here, the hybrid modules with broad expression strength may benefit the application of QS-based autoinduction systems in B. subtilis.

[Application of isotemporal substitution model in epidemiological research]

Isotemporal substitution model is a powerful tool to explore the real association between physical behavior and health outcomes, which has the potential of the application in large-scale cohort study. This paper systematically introduces the principle of isotemporal substitution model and its implementation method in specific analysis to provide analytical ideas for the epidemiological research related to physical behavior in China. The baseline data of Regional Ethic Cohort Study in Northwest China conducted in Shaanxi province were used to analyze the relationship between physical behavior and cardiovascular disease with single-factor model, partition model and isotemporal substitution model. The advantages and disadvantages of different models were compared, and the advantages of isotemporal substitution model in quantifying physical activity health risk were introduced. Isotemporal substitution model could qualify physical behavior and health outcomes, which has wide application value in epidemiological research.

[Hepatic cystic echinococcosis complicated with tuberculous empyema misdiagnosed as hepatic and pulmonary cystic echinococcosis: one case report]

Hepatic cystic echinococcosis is a chronic parasitic disease caused by the infection with the larvae of Echinococcus granulosus in human or animal liver tissues. As a chronic active infectious disease, tuberculous empyema mainly invades the pleural space and then causes visceral and parietal pleura thickening. It is rare to present comorbidity for hepatic cystic echinococcosis and tuberculous empyema. This case report presents a case of hepatic cystic echinococcosis complicated with tuberculous empyema misdiagnosed as hepatic and pulmonary cystic echinococcosis, aiming to improve clinicians' ability to distinguish this disorder.

[Suitability of estimated urine protein using different estimated 24 h urine creatinine equations in children with glomerular diseases]

Objective: To assess the reliability of estimated urine protein to predict 24 h urine protein excretion in children with glomerular diseases. Methods: Four hundred and forty-three children with glomerular diseases, who were admitted to pediatric department of Peking University First Hospital from January 2001 to December 2021, were enrolled in the cross-sectional study. The 24 h estimated urine creatinine which calculated by 6 previously described equations, 24 h measured urine creatinine, measured urine protein-to-creatinine ratio(UPCR), 24 h urine protein (24 hUP) and urinary sediment analysis with microscopy were collected, estimated urine protein was computed as the product of measured UPCR and estimated or measured 24 h urine creatinine. Spearman correlation analysis, Bland-Altman analysis and linear regression analysis were used to compare the correlation, agreement and accuracy between estimated urine protein and 24 hUP, and the effect of urinary protein level and erythrocyte numbers on their relationship was analyzed. Results: Of 443 children with glomerular diseases (aged (11±4) years, 221 male, 222 female), there were 216 participants with nephrotic syndrome, 78 participants with IgA nephropathy, 47 participants with Alport syndrome, 42 participants with lupus nephritis, 58 participants with purpura nephropathy, and 2 participants with isolated proteinuria. Spearman correlation analysis showed a strong correlation between estimated urine protein and 24 hUP (r=0.90, P<0.05), and the correlation improved after multiplying the measured UPCR by 24 h measured urine creatinine (r=0.94, P<0.05). Improved correlation was also observed using the estimated urine creatinine which calculated by Hellerstein formula, Ghazali-Barratt formula, Ellam formula, Walser formula, Cockcroft-Gault formula, Ix formula (r=0.93, 0.94, 0.90, 0.90, 0.94, 0.93, all P<0.05).Bland-altman analysis showed that the difference between measured UPCR and 24 hUP was (-0.30±2.22) g, consistency limit was -4.65-4.04, and the consistency improved after 24 h measured urine creatinine correction (difference was (0.27±1.31) g, consistency limit -2.30-2.84). The consistency of estimated urine protein was further improved after correction by different formulas, and the Cockcroft-Gault formula showed the best consistency between estimated urine protein and 24 hUP (difference was (0.11±1.18)g, consistency limit was -2.20-2.42). Linear regression analysis showed that measured UPCR had poor accuracy in predicting 24 hUP (R²=0.55, α=0.48, β=0.60, P<0.05), and the accuracy improved after 24 h measured urine creatinine correction, the accuracy of estimated urine protein for predicting 24 hUP was further improved by using different formulas, and Cockcroft-Gault formula was the best (R²=0.81, α=0.18, β=0.96, P<0.05). With the increase of urinary protein level and the decrease of urinary erythrocyte numbers, the correlation, agreement and accuracy between estimated urine protein and measured UPCR and 24 hUP were improved(all P<0.05). Except Ellam and Ix formulas, estimated urine protein using the rest four formulas outperformed measured UPCR(all P<0.05). Conclusion: The 24 h urine creatinine excretion rate (obtained by the Cockcroft-Gault equation)-weighted urine protein-to-creatinine ratio more reliably predicts 24 hUP than measured UPCR alone in children with glomerular diseases.

[A case of mild Zellweger spectrum disorder first diagnosed as Usher syndrome]

A 5-year-old female patient, presented with"night blindness and poor hearing for 1 year"whose first diagnosis was Usher syndrome due to retinitis pigmentosa accompanied by sensorineural deafness. Compound heterozygous variants (c.5G>A, p.W2*/c.3022C>T, p.P1008S) of PEX1, the causative gene for Zellweger spectrum disorder was confirmed by targeted exome sequencing analysis. Permanent tooth enamel dysplasia, nail leukoplakia, and biochemical abnormalities of peroxisome which is consistent with mild Zellweger spectrum disorder were found when she followed up.

[hsa_circ_0000231 affects the progression of tongue squamous cell carcinoma by activating Wnt/β-catenin signaling pathway]

Objective: To explore the action mechanism of hsa_circ_0000231 in the occurrence and development of tongue squamous cell carcinoma (TSCC). Methods: Tissue samples of 60 TSCC patients were examined. The patients, including 32 males and 28 females, aged from 36 to 84 years old, underwent surgery in the Affiliated Hospital of Nantong University and Affiliated Tumor Hospital of Nantong University from December 2014 to December 2017. Saliva samples were obtained from healthy volunteers (5 males and 5 females, aged from 40 to 75 years old) and 10 TSCC patients. The TSCC cell lines (CAL-27, Tca-8113 and HN-4) were used. The expression levels of hsa_circ_0000231 in 60 pairs of freshly matched TSCC and para-carcinoma tissue samples, 10 pairs of saliva samples and 3 TSCC cell lines were detected by quantitative real-time polymerase chain reaction (qRT-PCR). hsa_circ_0000231 gene interference and lentiviral transfection were constructed, hsa_circ_0000231 in TSCC cell lines CAL-27 and Tca-8113 was knocked down, and the expressions of hsa_circ_0000231 in hsa_circ_0000231 interference group (sh-circ) and no-load lentivirus group (negative control) were tested with qRT-PCR. Cells with the highest knock-down efficiency were selected for CCK-8 test, colony formation assay, transwell invasion assay and scratch assay. The expressions of EMT-related proteins including E-cadherin, snail protein, N-cadherin and vimentin and proteins related to Wnt/β-catenin signaling pathway including β-catenin, C-myc, Bcl-2, MMP-9 and Cyclin D1 were measured by western blot. After TSCC cells in the interference group were co-cultured with Wnt/β-catenin pathway activator LiCl, the expressions of above proteins were re-measured by western blot. TSCC cells in interference group and control group were subcutaneously injected into nude mice to compare the effect of hsa_circ_0000231 knockdown on the growths of the tumors grafted subcutaneously in the nude mice. Statistical analysis software 25.0 was used for data analysis, and t-test or chi-square test was used for comparison between groups. Results: hsa_circ_0000231 was highly expressed in the tissue and saliva samples of TSCC patients and cell lines CAL-27, Tca-8113 and HN-4, but lowly expressed in paired para-carcinoma tissues, saliva samples of healthy people and normal human oral keratinocytes (all P<0.05). Log-rank univariate analysis showed that hsa_circ_0000231 expression level, tumor differentiation degree and T stage were related to the survival of TSCC patients (all P<0.05). Multivariate Cox risk regression model analysis suggested that hsa_circ_0000231 expression level (χ²=5.77,P=0.016) and T stage (χ²=5.27,P=0.029) were independent factors for the poor prognosis of TSCC patients. Western blot showed the expressions of snail protein, N-cadherin and vimentin were down-regulated, but E-cadherin was up-regulated in interference group compared with control group. In interference group, the expressions of β-catenin, C-myc, Bcl-2, MMP-9 and CyclinD1 were down-regulated, which were reversed after TSCC cells were co-cultured with LiCl. The knockdown of hsa_circ_0000231 reduced the proliferation, invasion and metastasis abilities of CAL-27 and Tca-8113 cells, which were reversed after TSCC cells were co-cultured with LiCl. The growth rate and volume of the tumors grafted subcutaneously in interference group using LiCl were greater than those in negative control group. Conclusion: hsa_circ_0000231 is an independent prognostic factor of TSCC. Highly expressed hsa_circ_0000231 can promote the proliferation, invasion and metastasis of TSCC cells.

[Analysis of effective connectivity in default mode network in male long-term smokers based on dynamic causal modeling]

Objective: To investigate the alterations in effective connection of default mode network (DMN) in long-term male smokers and its correlation with clinical characteristics of smoking. Methods: A total of 131 subjects through WeChat platform and underwent resting-state functional magnetic resonance (rs-fMRI) examinations were recruited, including 76 long-term smokers [long-term smoking group, male, aged 20 to 55 (32.1±6.3) years] and 55 non-smokers [healthy controls, male, aged 20 to 55(32.3±7.4) years] from January 2014 to December 2018. Long-term smokers were defined as those who smoked at least 10 cigarettes per day for more than 2 years, and met the Diagnostic and Statistical Manual of Mental Disorders-Four Edition (DSM-Ⅳ) criteria for substance dependence. Four major nodes of DMN, including left inferior parietal lobule (LIPL), right inferior parietal lobule (RIPL), posterior cingulate cortex (PCC), medial prefrontal cortex (mPFC) were chosen as for the region of interest. The effective connectivity (EC) alterations of DMN between smoking group and healthy controls were compared using dynamic causal modeling (DCM). The correlation between EC with significant difference among the two groups and Nicotine Dependence Scale (FTND) score, pack-year score and smoking duration were evaluated. Results: Compared to the healthy controls, the EC of LIPL to PCC and PCC to mPFC were decreased in the smoking group (EC = -0.091, -0.174, respectively, Bayesian-PP>0.95), and the EC of RIPL to PCC was increased (EC = 0.136, Bayesian-PP>0.95). Besides, EC of LIPL to PCC showed negative correlation with pack-year scores(r=-0.282,P=0.017). No significant linear correlations were observed between EC with significant group difference and FTND score or smoking duration (r=-0.103、-0.089,all P>0.05). Conclusion: Long-term smokers showed multiple abnormalities in IPL-PCC-mPFC circuits, and associated with the pack-year scores.

[Comparative analysis on prevalence of tobacco and e-cigarettes uses in junior middle school students in Shanghai, 2013 and 2019]

Objective: To examine the prevalence and trend of tobacco and e-cigarettes uses and identify the influencing factors for smoking behavior in junior middle school students in Shanghai, and provide data support and scientific basis for the development of tobacco control intervention strategy in adolescents. Methods: Multi-stage stratified random sampling method was used to select junior middle school students in 8 districts and 10 districts in Shanghai in 2013 and in 2019 respectively. Information about tobacco and e-cigarettes uses in the students were collected by using self-administrated questionnaire. The prevalence of tobacco and e-cigarettes uses were calculated, the difference between two years was compared with χ² test. The influencing factors were identified by multivariate logistic regression analysis. Results: In 2019, the current smoking rate was 0.6% in junior middle school students in Shanghai, and the smoking attempt rate was 2.9%, both were lower than the levels in 2013 (0.7% and 6.9%). The current use rate of e-cigarettes was 0.6% in 2019,with no significant change compared with 2013 (0.6%). The proportion of the students who had heard of e-cigarettes in 2019 (78.4%) was higher than that in 2013 (47.2%). In 2019, the second-hand smoke (SHS) exposure rate at home, in both indoor and outdoor public places and on public transportations was 72.5%, which was slightly lower than the level in 2013 (73.0%), the differences were all significant (P<0.05). In 2019, the students seeing close friend smoking (OR=27.381, 95%CI: 12.037-62.287), seeing someone smoking in school (OR=2.477, 95%CI: 1.155-5.312), believing that SHS may not be harmful (OR=8.471, 95%CI: 1.464-49.005) had higher possibility of smoking. Being aged ≥15 years (compared with being aged ≤12 years, OR=8.688, 95%CI: 1.922-39.266), exposure to SHS in outdoor public place (OR=8.608, 95%CI: 1.048-70.692), close friend smoking (OR=8.115, 95%CI: 1.754-37.545) were positively associated with e-cigarettes use, and believing that smoking results in uncomfortable social contact [compared with believing that smoking results in comfortable social contact (OR=0.105,95%CI: 0.018-0.615)] were negatively associated with e-cigarettes use, the difference was significant (P<0.05). Conclusion: The prevalence of tobacco and e-cigarette uses in junior middle school students in Shanghai remained at a low level in recent years. The SHS exposure rate in junior middle school students is high. Smoking behavior of junior middle school students is closely related to personal attitude and awareness of tobacco, exposure to SHS, peer smoking and the situation of tobacco control in schools. Prevention and intervention should be carried out from multi-dimensions to effectively protect teenagers from tobacco hazards.

[C1q or IgA deposition in glomeruli of children with primary membranous nephropathy]

Objective: To assess the correlation of glomerular C1q or IgA deposition with clinical and pathological features of primary membranous nephropathy (PMN) in children. Methods: The clinical and pathological manifestations including (phospholipase A2 receptor, PLA2R) and IgG subclasses staining in renal biopsies, serum anti-PLA2R antibody and therapeutic response of 33 children diagnosed with PMN in Peking University First Hospital from December 2012 to December 2020 were retrospectively summarized and analyzed. According to results of PLA2R test and findings renal pathological, the patients were divided into PLA2R-related group and non-PLA2R-related group, typical MN group and atypical MN group, C1q deposit group and non-C1q deposit group, as well as IgA deposit group and non-IgA deposit group respectively. T-test, Mann-Whitney U test and Fisher's exact probability test were used for comparison between the groups. Results: Among the 33 children with PMN, there were 20 males and 13 females, of that the age of onset was 11 (8, 13) years, and 32 patients had nephrotic level proteinuria. Renal biopsies were performed at 4.6 (2.1, 11.6) months after onset, and 28 patients (85%) received glucocorticoid or immunosuppressive therapy prior to renal biopsy. There were 20 cases (61%) with PLA2R-related MN and 13 cases (39%) with non-PLA2R-related MN. Compared with the non-PLA2R-related group, the PLA2R-related group had an older age of onset (12 (10, 13) vs. 7 (3, 12) years, Z=-2.52, P=0.011), a lower preceding infection rate (45% (9/20) vs. 11/13, P=0.032) and lower spontaneous remission rate (0 vs. 4/13, P=0.017). Renal PLA2R positivity was significantly associated with predominant or co-deposition of IgG4 (13/17 vs. 5/15, P=0.031) and low albumin levels at renal biopsy ((25±6) vs. (29±7) g/L, t=2.14, P=0.041). There were 12 patients with typical PMN and 21 patients with atypical PMN, and no significant difference in clinical and pathological manifestations was found between these 2 groups (all P>0.05). There were 10 cases (32.3%) with glomerular C1q deposition, and their disease course before renal biopsy was significantly shorter than those without C1q deposition (1.8 (0.8, 5.9) vs. 6.0 (2.5, 22.3) months, Z=-2.27, P=0.023). Twelve cases (36.4%) had glomerular IgA deposition, and their course of disease,clinical and pathological manifestations were not significantly different from those without IgA deposition (all P>0.05). Conclusion: Glomerular C1q or IgA deposition may not affect the clinical manifestations, glomerular PLA2R and IgG subclasses staining pattern, or the response to treatment of PMN in children.

Evaluating short-term outcomes of the value of sound touch elastography (STE) following the treatment for Budd-Chiari syndrome (BCS): a case series study

AIM

To investigate the value of sound touch elastography (STE) in the evaluation of short-term therapeutic effect of Budd-Chiari syndrome (BCS) by measuring liver stiffness (LS), and in addition, to analyse the relationships between liver function, pressure gradient of the hepatic veins, and LS.

MATERIALS AND METHODS

A case series study was conducted at Affiliated Hospital of Xuzhou Medical University from August 2020 to December 2020. Patients diagnosed with BCS were recruited prospectively and grouped according to Child-Pugh grade before endovascular therapy. LS was measured using STE before and after therapy. Comparisons between the LS and hepatic venous pressure gradient (HVPG) changes of patients were tested with paired sample t-tests.

RESULTS

A total of 46 patients (23 males and 23 females) were included in this study. According to the Child-Pugh scoring criteria, 24 patients were classified as grade A, 16 as grade B, and 6 as grade C. LS was significantly different between the three groups (F = 127.01, p<0.001). Post-treatment LS was significantly lower than pre-treatment (p<0.001). The mean HVPG before treatment was 13.02 ± 3.82 mmHg and decreased after intervention (p<0.001).

CONCLUSION

The STE is a potential tool for evaluating short-term therapeutic effect of BCS patients.

Morphology, molecular phylogeny and systematics of the diatom genus Fallacia (Sellaphoraceae), with descriptions of three new species1

Fallacia is distinguished morpho-anatomically from Navicula sensu lato based on the possession of an H-shaped chloroplast, lateral sterna and a finely porous conopeum, but whether this genus is monophyletic is still in question. Three new Fallacia species are described based on morphology and SSU rRNA and rbcL gene sequences: Fallacia tateyamensis sp. nov., Fallacia bosoensis sp. nov. and Fallacia laevis sp. nov. We performed the first comprehensive molecular and morphological phylogenetic analyses of 31 Fallacia species based on 11 new sequences from six species and 23 morphological characters. We also documented the detailed morphogenesis of Fallacia for the first time. Fallacia is not monophyletic. Both morphological and DNA sequence data supported the separation of Rossia from Fallacia, while the phylogenetic position of Pseudofallacia is uncertain. We recognized four morphogroups in Fallacia by morphological and molecular phylogenetic analyses. Ancestral character reconstruction indicated that diatoms in Sellaphoraceae evolved from the possession of two lateral narrow parallel depressions covered by narrow nonporous conopea, to lyre-shaped canals covered by wide porous conopea. Lanceolate canals and the presence of areolae in canals evolved multiple times independently.

A retrospective study of factors contributing to anchorage loss in upper premolar extraction cases

Background

Anchorage control is one of the components in the treatment of extraction cases. However, what determines more or less anchorage loss is still an unanswered question. Aim: The purpose of this study was to investigate the most important factors contributing to the anchorage loss of maxillary first molars in premolar extraction cases.

Materials and Methods

The study included 726 upper premolar extraction cases, including 214 male patients and 512 female patients, and the mean age was 14.4 ± 4.5 years old (range: 9-45). Factors including physiological characteristics, treatment mechanics, and cephalometric variables were collected and their influences on the angulation changes of maxillary first molars were analyzed.

Results

The mean angulation change of maxillary first molar after treatment was 2.81°(mesial tipping). The change of UM/PP showed a statistically significant difference in different sex (male 3.84° ± 5.26° vs female 2.38° ± 5.10°), age (adult -0.05° ± 4.73° vs teenager 3.46° ± 5.07°), and molar relationship (Class II 3.28° ± 5.15° vs Class I 2.36° ± 5.19°). There are six variables accounted in the regression analysis (R = 0.608, R² = 37.0%). Among them, the pre-treatment molar tipping (Standardized Coefficients: -0.65) and the pre-treatment incisor/molar height ratio (Standardized Coefficients: -0.27) were the most important factors influencing anchorage loss during treatment.

Conclusion

Compared with treatment-related factors, the patient's physiological characteristics play a more important role in anchorage loss. The pre-treatment angulation of the maxillary first molar is the most influential factor in changes to maxillary molar angulation, which are often predisposing anchorage loss.

[Consensus of experts on the medical risk prevention for the patients with cardiovascular diseases during dental treatment (2022 edition)]

With the aging process of population in the society, the prevalence of cardiovascular diseases (CVD) in China is increasing continuously and the number of dental patients with CVD is increasing gradually too. Due to the lack of guidelines for dental patients with CVD in our country, how to implement standardized preoperative evaluation and perioperative risk prevention remains a problem to be solved for dentists at present. The present expert consensus was reached by combining the clinical experiences of the expert group of the Fifth General Dentistry Special Committee, Chinese Stomatological Association and respiratory and cardiology experts in diagnosis and treatment for CVD patients, and by systematically summarizing the relevant international guidelines and literature regarding the relationship between CVD and oral diseases and the diagnosis and treatment of dental patients with heart failure, hypertension and antithrombotic therapy. The consensus aims to provide, for the dental clinicians, the criteria on diagnosis and treatment of CVD in dental patients in China so as to reduce the risk and complications, and finally to improve the treatment levels of dental patients with CVD in China.

[Transoral robotic surgery for treatment of lingual thyroglossal duct cyst]

Objective: To investigate the feasibility, safety and efficacy of transoral robotic surgery (TORS) in the treatment of lingual thyroglossal duct cyst (LTGDC). Methods: The clinical data of 10 patients with LTGDC treated with TORS in Tongji Hospital affiliated to Tongji Medical College of Huazhong University of Science and Technology from May 2017 to November 2020 were analyzed retrospectively,including 6 males and 4 females, aged 5-44 years. The cysts were fully exposed, and resection usually started from the cephalic side of lesions. The range of resection was 3 to 5 mm away from the lesions, and partial hyoid bone was removed if necessary. Intra-operative robotic set-up time,operation time and estimated blood loss,and post-operative local bleeding, dyspnea and recovery time for oral intake were analyzed. SPSS 12.0 software was used for statistical analysis. Results: The cysts in all 10 patients were successfully resected by TORS with da Vinci Si surgical system. The mean robotic set-up and exposure time, operation time, estimated intraoperative blood loss and recovery time for oral intake were (15.5±7.1) min, (17.6±7.4) min, (8.9±6.4)ml and (2.3±2.2)days, respectively. No patient required tracheostomy intra-or post-operatively, and no symptoms of airway obstruction, postoperative bleeding, pharyngeal fistula, hoarseness and neurological impairment occurred after operation. The patients were followed up for 5 to 47 months, with median follow-up time of 17 months, and no recurrence was observed. Conclusion: TORS is safe and feasible for resection of LTGDC, with rapid recovery and low recurrence rate.

Bacteria, Protists, and Fungi May Hold Clues of Seamount Impact on Diversity and Connectivity of Deep-Sea Pelagic Communities

The topography and hydrography around seamounts have a strong influence on plankton biogeography. The intrinsic properties of various biological taxa inherently also shape their distribution. Therefore, it is hypothesized that different pelagic groups respond differently to effects of seamounts regarding their distribution and connectivity patterns. Herein, bacterial, protist, and fungal diversity was investigated across the water column around the Kocebu Guyot in the western Pacific Ocean. A higher connectivity was detected for bacteria than for protists and an extremely low connectivity for fungi, which might be attributed to parasitic and commensal interactions of many fungal taxa. The seamount enhanced the vertical connectivity of bacterial and protist communities, but significantly reduced protist connectivity along horizontal dimension. Such effects provide ecological opportunities for eukaryotic adaption and diversification. All the bacterial, protist, and fungal communities were more strongly affected by deterministic than stochastic processes. Drift appeared to have a more significant role in influencing the fungal community than other groups. Our study indicates the impact of seamounts on the pelagic community distribution and connectivity and highlights the mechanism of horizontally restricted dispersal combined with vertical mixing, which promotes the diversification of eukaryotic life.

A dark-tolerant diatom (Chaetoceros) cultured from the deep sea

Although the extreme conditions of the deep sea are typically not suitable for the growth of photosynthetic algae, accumulating evidence indicates that there are diverse healthy phytoplankton living in this environment. However, living phytoplankton from the deep sea have rarely been isolated and cultivated, and so our understanding of where they come from and how they adapt to (or tolerate) the extreme deep-sea environment is limited. Here, under long-term dark stress and subsequent light treatment, we successfully isolated a diatom from a depth of 1,000 m in the Western Pacific Ocean. Morphological observations and molecular phylogenetic analysis revealed that it is affiliated to the genus Chaetoceros, and thus, we tentatively named it Chaetoceros sp. DS1. We observed that the chloroplast genome of this species, is most closely related to that of Chaetoceros simplex. It was shown to have a strong tolerance to darkness in that it maintained its morphological integrity and vitality for up to 3 months in complete darkness at room temperature. We also demonstrated that Chaetoceros sp. DS1 presented a facultative heterotrophic function. Its growth was promoted by many organic carbon sources (e.g., glycerine, ethanol, and sodium acetate) under low light conditions. However, under dark and high light conditions, the growth promotion effect of organic carbon was not obvious. Indeed, Chaetoceros sp. DS1 grew best under low light conditions, indicating that it likely came from the deeper layer of the euphotic zone. The facultative heterotrophic function of this diatom and tolerance to darkness may help it survive in these conditions or enter a dormant period in the deep sea.