Waning immunity after receipt of Pertussis, Diphtheria, Tetanus and Polio-related vaccines: a systematic review and meta-analysis

DTP-containing (pertussis, diphtheria and tetanus) combined with polio vaccines are recommended by WHO as part of routine immunization programs. The decline of immunity after vaccination has been considered as a possible reason for the re-emergence of vaccine-preventable diseases worldwide. In this study, we evaluated the potential duration of protective immunity of pertussis, diphtheria, tetanus and polio through a systematic review and meta-analysis. We examined data on immunological and clinical outcomes. We observed evidence of waning post-vaccination immunity for pertussis and diphtheria, while tetanus and polio vaccines provided sustained protection. Further research on the risk factors of waning immunity after vaccination and the optimal timing of booster doses for pertussis and diphtheria are needed.

[Effects of melatonin on PBDE-47-induced abnormal autophagy and apoptosis in PC12 cells]

OBJECTIVE

To explore the effect of melatonin (MT) on 2, 2', 4, 4'-tetrabromodiphenylether (PBDE-47)-induced abnormal autophagy and apoptosis in rat adrenal medullary pheochromocytoma PC12 cells.

METHODS

PC12 cells were pretreated with a concentration gradient (12.5, 25, 50, 100, and 200 μmol/L) of melatonin for 2 h before exposure to 20 μmol/L PBDE-47 for 24 h to determine the optimal concentration of melatonin for cell treatment. In subsequent experiments, PC12 cells were treated with 0.5‰ DMSO (control group), 20 μmol/L PBDE-47, 25 μmol/L melatonin, or both PBDE-47 and melatonin. Immunofluorescence assay was used to detect the positive staining of microtubule associated protein 1 light chain 3 (LC3; a marker protein of autophagy); Western blotting was performed to determine the expression levels of the key autophagic proteins including autophagy-related protein 7 (ATG7), LC3-Ⅱ and autophagy substrate p62, and the key apoptotic proteins including active cysteine-containing aspartate specific protease-3 (active caspase-3) and cleaved poly(ADP ribose) polymerase (cleaved PARP).

RESULTS

PBDE-47 treatment significantly reduced the viability of PC12 cells (P=0.001), but pretreatment with 25 μmol/L melatonin maintained a cell viability over 80% following exposure to PBDE-47 (P=0.023). PBDE-47-treated PC12 cells showed obviously enhanced immunofluorescent staining of LC3 protein, a significantly decreased expression of ATG7 and increased expression levels of p62, LC3-Ⅱ, active caspase-3 and cleaved PARP (P < 0.001). The cells treated with both PBDE-47 and melatonin showed obviously reduced staining of LC3 protein with a signficantly increased expression level of ATG7 (P=0.034) and decreased expressions of p62 (P=0.048), LC3-Ⅱ (P=0.018), active caspase-3 (P < 0.001) and cleaved PARP (P=0.032).

CONCLUSION

PBDE-47 exposure impairs autophagy to cause autophagosome accumulation and promote apoptosis of PC12 cells. Melatonin can improve PBDE-47-induced abnormal autophagy and apoptosis and thus promote the survival of PC12 cells.

Manganese promoted wheat straw decomposition by regulating microbial communities and enzyme activities

AIMS

This study investigated the dose-effect of manganese (Mn) addition on wheat straw (WS) decomposition, and explored the potential mechanisms of Mn involved in the acceleration of WS decomposition in regards to the soil microbial communities and enzyme activities.

METHODS AND RESULTS

A 180-day incubation experiment was performed to examine the decomposition of WS under four Mn levels, that is, 0, 0.25, 1 and 2 mg g^-1 . The effects of microbial communities and enzyme activities were evaluated using control (0 mg g^-1 ) and Mn (0.25 mg g^-1 ) treatments. Our results revealed that Mn (0.25 mg g^-1 ) addition significantly increased WS decomposition, and enhanced the release of carbon and nitrogen. Optimal Mn addition (0.25 mg g^-1 ) also caused significant increases in the activity of neutral xylanase (NEX), laccase (Lac), manganese peroxidase (MnP) and lignin peroxidase (LiP) within the incubation period. Mn (0.25 mg g^-1 ) addition also enriched some operational taxonomic units (OTUs) that, in turn, had the potential ability to decompose crop straw, such as secreting lignocellulolytic enzymes.

CONCLUSIONS

Mn (0.25 mg g^-1 ) could promote WS decomposition through enrichment of the microbial species involved in biomass decomposition, which enhanced the lignocellulose-degrading enzyme activity.

SIGNIFICANCE AND IMPACT OF THE STUDY

This study provides evidence for Mn to promote WS biodegradation after Mn application, opening new windows to improve the utilization efficiency of crop residues.

[Clinical features and treatment prognoses of Pythium keratitis]

Objective: To analyze the clinical features and evaluate the prognoses of Pythium keratitis. Methods: It was a retrospective study. The clinical characteristics, confocal microscopic image characteristics, treatment and curative effect of 6 cases of Pythium keratitis identified by DNA sequencing from June 2017 to June 2019 were reviewed retrospectively. Results: Among the 6 patients, there were 4 males and 2 females. All cases were monocular. The age was (58.7±11.3) years (range, 52 to 72 years). Keratopathy under a slit lamp was characterized by a dry ulcer surface, burr signs, satellite foci and pseudopodia around the ulcer. An elevated lesion was observed in 2 patients, and no obvious immune ring structure was observed in all patients. Confocal microscopy did not reveal any specific characteristics of Pythium infection. All patients did not respond well to antifungal drugs and received keratoplasty. Three patients had postoperative recurrence. The recurrence time was 4-6 days after the first operation and 2-3 days after the second operation. Two patients underwent two and three corneal transplants, respectively, after recurrence, but evisceration was required finally. Conclusions: Pythium keratitis is rare and can hardly be distinguished from common fungal infections in clinical manifestations and auxiliary examinations. The disease progresses rapidly, the rates of recurrence and evisceration after keratoplasty are both high, and DNA sequencing is the key to identifying the etiology, which should be paid more attention. (Chin J Ophthalmol, 2021, 57: 589-594).

[The Ophthalmology-centered medical industry in Suzhou in the Ming and the Qing Dynasties - from the Painting Album of Cityscapes and Business]

The Painting Album of Cityscapes and Business was finished in the early Qing Dynasty with realism. This painting album described the prosperity in business and everyday life in Suzhou during the late Ming and the early Qing Dynasties. They were drawn and painted retrospectively, ie, the content of the pictures was based on existing paintings handed down. In the painting album, more than ten medical-related elements were specifically depicted, such as traditional Chinese medicine clinics and pharmacies and seven ophthalmology-related elements including one clinic specialized in ophthalmology, two spectacle shops, two people wearing eyeglasses and three blind people. Up to now, no specialized ophthalmology clinics and spectacle shops have been found in earlier literature and paintings. It can be speculated that the Painting Album of Cityscapes and Business is the earliest album of paintings depicting clinics specialized in ophthalmology and spectacle shops in China. This painting album provides important information for the study of the medical industry in Suzhou in the late Ming and the early Qing Dynasties, particularly, in terms of ophthalmology-related diagnosis and treatment.

Chicken C/EBPζ gene: Expression profiles, association analysis, and identification of functional variants for abdominal fat

CCAAT enhancer binding protein ζ (C/EBPζ) plays an important role in adipose proliferation and differentiation in humans. However, very little is known about the effect of C/EBPζ on the growth and development of adipose tissues in domesticated animals. The present study attempted to investigate the mRNA expression profiles of chicken C/EBPζ in a variety of tissues; analyze the association of its variants with abdominal fat; and identify the functional variants for abdominal fat. The tissue expression profiles revealed that C/EBPζ was highly expressed in 19 tissues obtained from broilers. The expression level of C/EBPζ in fat broilers was significantly lower than that in lean broilers in the duodenum, ileum, cecum, kidney, pectoral muscle, and liver (P < 0.05). Among 170 polymorphic loci of C/EBPζ, 9 single nucleotide polymorphisms (SNPs) demonstrated a significant association with chicken abdominal fat traits (P < 0.05) as well as significant discrepancies in their allelic frequencies between fat and lean birds. Particularly, only C/EBPζ g.7085A>C exhibited significant correlation with abdominal fat traits (P < 0.00015) using the Bonferroni method. The results revealed that, in preadipocyte immortalized cells (ICPI), the luciferase activity of the A allele of g.7085A>C locus was remarkably stronger than that of the C allele (P < 0.05). In silico analysis showed that g.7085A>C locus was located in the binding region of the transcription factor SOX5, which possesses the ability to transform C/EBPζ transcription efficiency through binding with SOX5. In summary, the data obtained from this study suggested that C/EBPζ is a potential candidate gene responsible for abdominal fat deposition in chicken and that g.7085A>C is a functional SNP that can be promisingly leveraged for marker assisted selection (MAS) in future chicken breeding programs.

Fizeau drag in graphene plasmonics

Dragging of light by moving media was predicted by Fresnel¹ and verified by Fizeau's celebrated experiments² with flowing water. This momentous discovery is among the experimental cornerstones of Einstein's special relativity theory and is well understood^3,4 in the context of relativistic kinematics. By contrast, experiments on dragging photons by an electron flow in solids are riddled with inconsistencies and have so far eluded agreement with the theory^5-7. Here we report on the electron flow dragging surface plasmon polaritons^8,9 (SPPs): hybrid quasiparticles of infrared photons and electrons in graphene. The drag is visualized directly through infrared nano-imaging of propagating plasmonic waves in the presence of a high-density current. The polaritons in graphene shorten their wavelength when propagating against the drifting carriers. Unlike the Fizeau effect for light, the SPP drag by electrical currents defies explanation by simple kinematics and is linked to the nonlinear electrodynamics of Dirac electrons in graphene. The observed plasmonic Fizeau drag enables breaking of time-reversal symmetry and reciprocity¹⁰ at infrared frequencies without resorting to magnetic fields^11,12 or chiral optical pumping^13,14. The Fizeau drag also provides a tool with which to study interactions and nonequilibrium effects in electron liquids.

[Preliminary study of the changes in blood system in pyrrolizidine alkaloid-related liver damage]

Objective: To preliminary explore the changes in blood system in pyrrolizidine alkaloids (PAs)-related liver damage. Methods: General situation, liver function, biochemical blood test, routine blood test, coagulation function markers, etc., of 77 cases with drug-induced liver damage admitted to the Zhongshan Hospital Affiliated to Fudan University from 2012 to 2019 were retrospectively analyzed. Patients' were divided into PA group, other traditional Chinese medicine group and Western medicine group according to their medication history. Simultaneously, the changes in liver function were observed in the established mice model of monocrotaline-induced liver damage. Liver tissues HE staining and blood routine indexes were observed. Results: 24 cases received PA, 24 cases received other traditional Chinese medicine, and 29 cases received western medicine. Alanine aminotransferase was lower in PA group than the other two groups (P < 0.05), and the total bilirubin and direct bilirubin were significantly lower than the other traditional Chinese medicine group (P < 0.05). The peripheral platelet count of the PA group was (84.11 ± 26.91) ×10(9)/L, which was significantly lower than the lower limit of normal, and had statistically significant difference with other traditional Chinese medicine and western medicine group (P < 0.01). Thrombocytocrit, mean platelet volume and platelet indices of PA group were statistically different from the other two groups (P < 0.05). The D-dimer level in patients with PA group was (2.62 ± 1.93) mg/L, which was higher than the upper limit of normal, and significantly higher than the D-dimer level of the other two groups of patients (P < 0.01). Meanwhile, prothrombin time was longer in PA group than that of the other two groups (P < 0.01), and platelets count were decreased significantly in the mouse model of monocrotaline-induced liver damage after alanine aminotransferase and aspartate aminotransferase elevation (P < 0.01). Conclusion: PA-related liver damage has lower peripheral platelet counts, and the peripheral platelet counts of these patients are lower than other types of drug-induced liver damage. In addition, increased D-dimer in patients with PA-related liver damage indicate a potential risk of thrombosis.

Serial intervals and case isolation delays for COVID-19: a systematic review and meta-analysis

Background

Estimates of the serial interval distribution contribute to our understanding of the transmission dynamics of coronavirus disease 2019 (COVID-19). Here, we aimed to summarize the existing evidence on serial interval distributions and delays in case isolation for COVID-19.

Methods

We conducted a systematic review of the published literature and preprints in PubMed on two epidemiological parameters namely serial intervals and delay intervals relating to isolation of cases for COVID-19 until 22 October, 2020 following predefined eligibility criteria. We assessed the variation in these parameter estimates by correlation and regression analysis.

Results

Of 103 unique studies identified on serial intervals of COVID-19, 56 were included providing 129 estimates and of 451 unique studies on isolation delays, 18 studies were included providing 74 estimates. Serial interval estimates varied from 1.0 to 9.9 days, while case isolation delays varied from 1.0 to 12.5 days which were associated with spatial, methodological and temporal factors. In mainland China, the pooled mean serial interval was 6.2 (range, 5.1-7.8) days before the epidemic peak and reduced to 4.9 (range, 1.9-6.5) days after the epidemic peak. Similarly, the pooled mean isolation delay related intervals were 6.0 (range, 2.9-12.5) days and 2.4 (range, 2.0-2.7) days before and after the epidemic peak, respectively. There was a positive association between serial interval and case isolation delay.

Conclusions

Temporal factors, such as different control measures and case isolation in particular led to shorter serial interval estimates over time. Correcting transmissibility estimates for these time-varying distributions could aid mitigation efforts.

The distinctive characteristics of the micro-vasculature and immune cell infiltration in cystic pancreatic neuroendocrine tumors

PURPOSE

Hypervascularity is a main characteristic of pancreatic neuroendocrine tumors (PanNETs), and cystic PanNETs (CPanNETs) are unique type of PanNETs in which the microenvironment remains unknown. We aim to compare the micro-vasculature features and immune cell infiltration between CPanNETs and solid PanNETs (SPanNETs).

METHODS

Data of 301 SPanNET and 36 CPanNET patients from a high-volume institution were evaluated. CD4, CD8, CD11c, CD15, CD20, CD68, CD34 and α-SMA expression levels were assessed by immunohistochemistry and immunofluorescent double staining. The microvessel density (MVD) and microvessel integrity (MVI) were examined.

RESULTS

MVD and MVI expression levels in CPanNETs were significantly higher than those in SPanNETs (p = 0.025 and 0.0092, respectively). CPanNETs had higher proportions of T1 (p = 0.023) and G1 (p = 0.052) than SPanNETs. In SPanNETs, higher MVD occurred in stages T1, N0 and G1 than in the T2/T3, N1 and G2 subgroups. In CPanNETs, CD34-MVD was uncorrelated with the T stage or grade. Higher CD34-MVD, but not MVI, was associated with better DFS (HR 0.3209, 95% CI 0.1259-0.8176, p = 0.004). There were significantly more peritumoral infiltrating immune cells than their intratumoral counterparts (p < 0.001 for each) in CPanNETs and SPanNETs. The mean number of peritumoral CD68 + TAM in CPanNETs was significantly lower than that in SPanNETs (p = 0.008). The counts of other peritumoral immune cells did not significantly differ between CPanNETs and SPanNETs.

CONCLUSIONS

CPanNETs had a microenvironment distinct from that of SPanNETs, including higher CD34-MVD, higher MVI and lower TAM. This specific microenvironment structure may partially help predicting the prognosis of patients with PanNET.

KIF2A regulates ovarian development via modulating cell cycle progression and vitollogenin levels

The kinesin superfamily of proteins (KIFs) are microtubule motor proteins that use the hydrolysis of ATP to power directional movement along microtubules. KIFs induce microtubule depolymerization to regulate the length and dynamics of microtubules in a variety of cell processes and structures, including the mitotic and meiotic spindles and centriole and interphase microtubules. KIF plays a significant role in the transport of organelles, protein complexes and mRNAs. The brown planthopper (Nilaparvata lugens) is a major insect pest in rice paddy fields. Ovarian development is regulated by multiple factors, including endocrine factors. The role of KIFs in brown planthopper ovarian development remains unknown. We found that downregulation of KIF2A significantly compromised the development and eclosion of the brown planthopper, delayed ovarian cell cycle progression, disrupted ovarian development, reduced the expression of MCM genes required for DNA replication and significantly reduced the number of nuclei in the follicles. We also found a significant reduction in Vg mRNA and protein levels. We conclude that downregulation of KIF2A disrupts the cell cycle progression of cells. Alternatively, the ovarian phenotype could be an indirect effect of a compromised trophic cord. In summary, KIF2A regulates ovarian development via modulating cell cycle progression and/or vitollogenin transportation.

Highly efficient self-trapped exciton emission in a one-dimensional face-shared hybrid lead bromide

A new one-dimensional (1D) face-shared hybrid lead bromide of (2cepiH)PbBr3, which exhibits intrinsic broadband yellow-light emission with a quantum yield of 16.8% outperforming all previously reported 1D face-shared hybrid metal halides, is obtained. The origin of broadband emission and the coexistence of free excitons and self-trapped excitons are deeply investigated by variable-temperature photoluminescence spectra. Our work paves the way to discovering more wonderful light-emitting materials.

Long noncoding RNA UCA1 promotes proliferation and metastasis of thyroid cancer cells by sponging miR-497-3p

OBJECTIVE

Recently, long noncoding RNAs (lncRNAs) have attracted much attention for their roles in tumor progression. The aim of this study was to investigate the exact role of lncRNA UCA1 in the development of thyroid cancer (TC) and to explore the possible underlying mechanism.

PATIENTS AND METHODS

UCA1 expression in both TC cells and tissues was detected by quantitative Real Time-Polymerase Chain Reaction (qRT-PCR). Colony formation assay, cell proliferation, and transwell assay were conducted in vitro. Subsequent luciferase reporter gene assay was applied to investigate the underlying mechanism. Furthermore, the function of UCA1 in vivo was monitored as well.

RESULTS

UCA1 expression level in TC samples was significantly higher than that of corresponding normal tissues. After UCA1 was knocked down in vitro and in vivo, the proliferation, migration, and invasion of TC cells were significantly inhibited. Moreover, the expression of miR-497-3p was repressed after the knockdown of UCA1. Furthermore, miR-497-3p was directly targeted by UCA1.

CONCLUSIONS

Knockdown of UCA1 could inhibit TC cell proliferation and metastasis via sponging miR-497-3p. Our findings might offer a new therapeutic intervention for TC patients.

Tipping the immunostimulatory and inhibitory DAMP balance to harness immunogenic cell death

Induction of tumor cell death is the therapeutic goal for most anticancer drugs. Yet, a mode of drug-induced cell death, known as immunogenic cell death (ICD), can propagate antitumoral immunity to augment therapeutic efficacy. Currently, the molecular hallmark of ICD features the release of damage-associated molecular patterns (DAMPs) by dying cancer cells. Here, we show that gemcitabine, a standard chemotherapy for various solid tumors, triggers hallmark immunostimualtory DAMP release (e.g., calreticulin, HSP70, and HMGB1); however, is unable to induce ICD. Mechanistic studies reveal gemcitabine concurrently triggers prostaglandin E2 release as an inhibitory DAMP to counterpoise the adjuvanticity of immunostimulatory DAMPs. Pharmacological blockade of prostaglandin E2 biosythesis favors CD103+ dendritic cell activation that primes a Tc1-polarized CD8+ T cell response to bolster tumor rejection. Herein, we postulate that an intricate balance between immunostimulatory and inhibitory DAMPs could determine the outcome of drug-induced ICD and pose COX-2/prostaglandin E2 blockade as a strategy to harness ICD.

Influenza versus COVID-19 cases among influenza-like illness patients in travelers from Wuhan to Hong Kong in January 2020

OBJECTIVE

The COVID-19 outbreak in Wuhan, Hubei, China, followed the seasonal influenza epidemic. Since some COVID-19 cases may have been misdiagnosed as seasonal influenza in January 2020, before testing capacity was adequate, it is relevant to study the proportions of influenza and COVID-19 cases among influenza-like-illness (ILI) patients and their temporal pattern.

RESULTS

This study analyzed the record of the ILI patients with a recent travel history to Wuhan who arrived in Hong Kong between 31 December 2019 and 21 January 2020. We found that the proportion of COVID-19 cases among the total ILI patients is much smaller than a study among ILI in Wuhan. This difference in proportion could be due to the difference in sampling. We argue that it is essential to consider both samples when inferring the number of COVID-19 cases from ILI patients.

No pulsed radio emission during a bursting phase of a Galactic magnetar

Fast radio bursts (FRBs) are millisecond-duration radio transients of unknown physical origin observed at extragalactic distances^1-3. It has long been speculated that magnetars are the engine powering repeating bursts from FRB sources^4-13, but no convincing evidence has been collected so far¹⁴. Recently, the Galactic magnetar SRG 1935+2154 entered an active phase by emitting intense soft γ-ray bursts¹⁵. One FRB-like event with two peaks (FRB 200428) and a luminosity slightly lower than the faintest extragalactic FRBs was detected from the source, in association with a soft γ-ray/hard-X-ray flare^18-21. Here we report an eight-hour targeted radio observational campaign comprising four sessions and assisted by multi-wavelength (optical and hard-X-ray) data. During the third session, 29 soft-γ-ray repeater (SGR) bursts were detected in γ-ray energies. Throughout the observing period, we detected no single dispersed pulsed emission coincident with the arrivals of SGR bursts, but unfortunately we were not observing when the FRB was detected. The non-detection places a fluence upper limit that is eight orders of magnitude lower than the fluence of FRB 200428. Our results suggest that FRB-SGR burst associations are rare. FRBs may be highly relativistic and geometrically beamed, or FRB-like events associated with SGR bursts may have narrow spectra and characteristic frequencies outside the observed band. It is also possible that the physical conditions required to achieve coherent radiation in SGR bursts are difficult to satisfy, and that only under extreme conditions could an FRB be associated with an SGR burst.

Long noncoding RNA SNHG14 accelerates cell proliferation, migration, invasion and suppresses apoptosis in colorectal cancer cells by targeting miR-944/KRAS axis through PI3K/AKT pathway

OBJECTIVE

Colorectal cancer (CRC) is a gastrointestinal tract cancer, which threatens the well-being of million of patients due to high metastasis. Recently, numerous studies have recognized nuclear RNA host gene 14 (SNHG14) as a remarkable oncogene in different cancers. However, the regulatory mechanism of SNHG14 in CRC development is mostly unclear.

PATIENTS AND METHODS

The expression of SNHG14, miR-944 and Kirsten rat sarcoma (KRAS) in tissues and cells was measured by quantitative Real-time polymerase chain reaction (qRT-PCR). Cell viability and apoptosis were evaluated by cell counting kit-8 (CCK-8) and flow cytometry assay, respectively. Cell migration and invasion were assessed using transwell assay. Protein expression of KRAS, AKT, phosphorylated AKT (p-AKT), phosphatidylinositol-3-kinase (PI3K) and phosphorylated PI3K (p-PI3K) was detected by Western blot. Animal models were constructed by subcutaneously injecting SW620 cells stably transfected with sh-SNHG14 and sh-NC. The interaction among SNHG14, miR-944 and KRAS was determined by luciferase reporter assay and RIP assay.

RESULTS

The expression of SNHG14 and KRAS was up-regulated whereas miR-944 was down-regulated in CRC tumors and cells compared with normal tissues and cells. In addition, SNHG14 silencing attenuated cell proliferation, migration and invasion, while accelerated apoptosis in CRC cells by suppressing PI3K/AKT pathway. Consistently, SNHG14 knockdown hindered tumor growth in vivo. MiR-944 was a target of SNHG14 and directly targeted KRAS. Moreover, miR-944 inhibitor abrogated silenced SNHG14-mediated inhibition on proliferation, migration and invasion, as well as promotion on apoptosis in CRC cells. Similarly, miR-944 regulated CRC cell progression by targeting KRAS through PI3K/AKT pathway.

CONCLUSIONS

SNHG14 contributed to cell proliferation, migration and invasion, while suppressed apoptosis in CRC cells by targeting miR-944/KRAS axis through PI3K/AKT pathway, representing novel biomarkers for CRC therapy.

Gastric cancer nodal tumour-stroma ratios influence prognosis

This study showed that nodal tumour-stroma ratio (NTSR) is an independent prognostic factor for overall and disease-free survival of patients with gastric cancer. Both relative stroma-rich primary tumour-stroma ratio (PTSR) and NTSR were independent negative prognostic factors for overall survival in gastric cancer. This study supports assessment of tumour-stroma ratio in the routine pathological diagnosis of gastric cancer. validated in node-positive disease.

STAT3-induced upregulation of lncRNA SNHG17 predicts a poor prognosis of melanoma and promotes cell proliferation and metastasis through regulating PI3K-AKT pathway

OBJECTIVE

Long noncoding RNAs (lncRNAs) have drawn increasing attention due to their critical roles in various diseases, including melanoma. In this study, we aimed to explore the potential roles and underlying mechanisms of Small nucleolar RNA host gene 17 (SNHG17) in the modulation of melanoma progression.

PATIENTS AND METHODS

The levels of SNHG17 in melanoma tissues and cells were determined using RT-PCR. The clinical significance of SNHG17 in melanoma patients was analyzed using Chi-square tests, Kaplan-Meier methods, and multivariate assays. MTT assays, transwell assay, and flow cytometry were carried out to explore the biological functions of SNHG17. The biological mechanism underlying up-regulation of SNHG17 was explored using ChIP analysis and luciferase reporter assays. The related proteins of the PI3K-AKT pathway were determined by Western blot.

RESULTS

High expressions of SNHG17 were observed in both melanoma tissues and cells. Up-regulation of SNHG17 in melanoma patients was associated with lymph node metastasis and tumor stage. Survival assays revealed that those patients with high SNHG17 expression had significantly shorter survival time. SNHG17 was also confirmed to be independently associated with overall survival of melanoma patients. Functional studies confirmed that the proliferation, migration, and invasion of melanoma cells were noticeably reduced by the down-regulation of SNHG17. Mechanistically, the up-regulation of SNHG17 was induced by STAT3. We also found that knockdown of SNHG17 resulted in the remarkable diminution in the phosphorylation levels of PI3K and AKT, suggesting that the activity of the PI3K-AKT pathway was suppressed.

CONCLUSIONS

STAT3-induced upregulation of SNHG17 contributed to the progression of melanoma by promoting the PI3K-AKT signaling.

LncRNA LINC00342 regulated cell growth and metastasis in non-small cell lung cancer via targeting miR-203a-3p

OBJECTIVE

Non-small cell lung cancer (NSCLC) is the main form of lung cancer, leading to major causes of cancer mortality. It is well known that lncRNAs may be involved in the pathogenesis of cancer, including NSCLC. The aim of this study was to provide a novel therapeutic target of LINC00342 for the therapy of NSCLC.

PATIENTS AND METHODS

The expression of LINC00342 and miR-203a-3p was detected by quantitative Real Time-Polymerase Chain Reaction (qRT-PCR). Cell proliferation was measured using the MTT assay. Colony formation analysis was performed to count the number of colonies. Cell migration and invasion were measured by transwell. Online software DIANA tools were used to predict binding sites of LINC00342 and miR-203a-3p. Luciferase reporter assay was conducted to confirm the interaction between LINC00342 and miR-203a-3p.

RESULTS

The expression of LINC00342 was increased in NSCLC tissues and cells compared with normal tissues and cells. Knockdown of LINC00342 suppressed cell proliferation, colony formation, migration, and invasion. LINC00342 regulated the expression of miR-203a-3p by targeting it directly. MiR-203a-3p was down-regulated in NSCLC tissues and cells compared with normal tissues and cells. Furthermore, LINC00342 promoted NSCLC cells proliferation, colony formation, migration, and invasion by depleting the expression of miR-203a-3p.

CONCLUSIONS

This work implied that LINC00342 functions in NSCLC acting as an oncogene. Briefly, LINC00342 contributes to NSCLC cells growth and metastasis via targeting miR-203a-3p competitively.

Dynamical Order and Superconductivity in a Frustrated Many-Body System

In triangular lattice structures, spatial anisotropy and frustration can lead to rich equilibrium phase diagrams with regions containing complex, highly entangled states of matter. In this work, we study the driven two-rung triangular Hubbard model and evolve these states out of equilibrium, observing how the interplay between the driving and the initial state unexpectedly shuts down the particle-hole excitation pathway. This restriction, which symmetry arguments fail to predict, dictates the transient dynamics of the system, causing the available particle-hole degrees of freedom to manifest uniform long-range order. We discuss implications of our results for a recent experiment on photoinduced superconductivity in κ-(BEDT-TTF)_{2}Cu[N(CN)_{2}]Br molecules.

Early Insights from Statistical and Mathematical Modeling of Key Epidemiologic Parameters of COVID-19

We report key epidemiologic parameter estimates for coronavirus disease identified in peer-reviewed publications, preprint articles, and online reports. Range estimates for incubation period were 1.8–6.9 days, serial interval 4.0–7.5 days, and doubling time 2.3–7.4 days. The effective reproductive number varied widely, with reductions attributable to interventions. Case burden and infection fatality ratios increased with patient age. Implementation of combined interventions could reduce cases and delay epidemic peak up to 1 month. These parameters for transmission, disease severity, and intervention effectiveness are critical for guiding policy decisions. Estimates will likely change as new information becomes available.

The Ca2+ -regulated protein kinase CIPK1 integrates plant responses to phosphate deficiency in Arabidopsis thaliana

Phosphate (Pi) deficiency severely restricts plant growth and development, as Pi is an essential macronutrient. Calcium (Ca²⁺ ) is a ubiquitous second messenger in plants; calcineurin B-like proteins (CBL) and CBL-interacting protein kinases (CIPK) are signalling pathways that act as an important Ca²⁺ signalling network which integrates plants to fine tune the response to stress; however, whether CIPK are involved in Pi deficiency stress remains largely unknown. In this study, we carried out a reverse genetic strategy to screen T-DNA insertion mutants of CIPK isoforms under Pi deficiency in Arabidopsis thaliana. Then Pi content, transcription of phosphate starvation-induced (PSI) genes, acid phosphatase activity and hydrogen peroxide were determined in the wild-type (WT) and cipk1 mutant, respectively. The phenotype of CIPK1 complementation lines was analysed. The cipk1 mutant had a more sensitive phenotype, with lower root elongation and root length, and decreased Pi content compared with the WT under Pi deficiency. Moreover, CIPK1 mutation caused phosphate starvation-induced (PSI) genes to be significantly induced under Pi deficiency. Histological staining demonstrated that the cipk1 mutant had increased acid phosphatase activity and hydrogen peroxide concentration under Pi deficiency. By using the yeast two-hybrid system, we further demonstrated the interaction between CIPK1 and the WRKY transcription factors, WRKY6 and WRKY42. Overall, we demonstrate that CIPK1 is involved in the Pi deficiency signalling pathway in A. thaliana, revealing the important role of Ca²⁺ in the Pi nutrition signalling pathway, and potentially providing a theoretical foundation for molecular breeding of crops with better Pi utilization efficiency.

[Clinical feature changes of a COVID-19 patient from mild to critical condition and cardiopulmonary pathological results]

Objective: To analyse the clinical history, laboratory tests and pathological data of a patient who suffered from novel coronavirus pneumonia(COVID-19) and provide reference for the clinical treatment of similar cases. Methods: Data of clinical manifestation, laboratory examination, bronchoscopy, echocardiography and cardiopulmonary pathological results were retrospectively reviewed in a case of COVID-19 with rapid exacerbation from mild to critical condition. Results: This patient hospitalized at day 9 post 2019 novel coronavirus(2019-nCoV) infection, experienced progressive deterioration from mild to severe at day 12, severe to critical at day 18 and underwent extracorporeal membrane oxygenation(ECMO) and continuous renal replacement therapy(CRRT) as well as heart lung transplantation during day 28-45 post infection, and died at the second day post heart and lung transplantation. The patient had suffered from hypertension for 8 years. At the early stage of the disease, his symptoms were mild and the inflammatory indices increased and the lymphocyte count decreased continuously. The patient's condition exacerbated rapidly with multi-organ infections, and eventually developed pulmonary hemorrhage and consolidation, pulmonary hypertension, right heart failure, malignant ventricular arrhythmias, liver dysfunction, etc. His clinical manifestations could not be improved despite viral RNAs test results became negative. The patient underwent lung and heart transplantation and finally died of multi organ failure at the second day post lung and heart transplantation. Pathological examination indicated massive mucus, dark red secretions and blood clots in bronchus. The pathological changes were mainly diffused pulmonary hemorrhagic injuries and necrosis, fibrosis, small vessel disease with cardiac edema and lymphocyte infiltration. Conclusions: The clinical course of severe COVID-19 can exacerbate rapidly from mild to critical with lung, liver and heart injuries.

Age, source, and future risk of COVID-19 infections in two settings of Hong Kong and Singapore

Objective

To explore and compare the age, source and future risk of COVID-19 infection in Hong Kong SAR China and Singapore as of March 5, 2020.

Results

We find significant difference in age patterns of confirmed cases in these 2 localities early in the pandemic.

Conclusion

We highlight the potential importance of population age structure in confirmed cases, which should be considered in evaluation of the effectiveness of control effort in different localities.

[Bronchiolar adenoma: a clinicopathological analysis of 15 cases]

Objective: To study the clinicopathological characteristics, diagnosis and differential diagnosis of bronchiolar adenoma (BA). Methods: Fifteen cases of BA were collected from the First Affiliated Hospital of Nanjing Medical University, from January 2016 to October 2019. The clinical data, imaging examination, morphology, immunostaining and molecular changes were retrospectively analyzed. Results: There were 3 males, 12 females, most of the patients were female, mainly in middle-aged to elderly (51-77 years). Three had smoking history. The patients usually had no clinical symptoms. Imaging findings were ground-glass and/or lobulated nodules. Grossly, the tumors were gray-whitish, taupe solid or focally microcystic nodules with distinct boundary but no capsule. The maximum diameter was 0.4-2.5 cm (mean 1.0 cm). Histologically, there were glandular, papillary, or flat patterns that were composed of basal cells, mucous cells, ciliated cells and type Ⅱ pneumocytes, some of which showed basal cell proliferation and squamous cell metaplasia. However, there were some cases with few or even without mucous and/or ciliated cells. Immunostaining highlighted the continuous basal cell layer (positive for p63, p40 and cytokeratin 5/6), which was the most important diagnostic evidence. Genetic tests did not show mutation in BRAF or EGFR genes. All patients were followed up for 1-41 months, and they were without recurrence or metastasis. Conclusions: BA is a benign neoplasm that develops in the peripheral lung with good prognosis. Definite diagnosis is very crucial for surgical treatment, especially in frozen consultation. Immunohistochemistry will be helpful if necessary.

FRI0261 DIFFERENTIAL EXPRESSION OF PERIPHERAL CD4+ T CELLS IN PATIENTS WITH SYSTEMIC SCLEROSIS AND MIXED CONNECTIVE TISSUE DISEASE

Background:

The CD4+T cell subsets plays an important role in its pathogenesis, and its new research are constantly being published, but its specific changes between SSc and MCTD are still unclear.

Objectives:

The aim of the present study was to explore the absolute numbers of CD4+T subsets in peripheral blood(PB) of patients with SSc and MCTD using our modified flow cryometric method and investigate the role in the pathogenesis of both.

Methods:

The PB samples from 54 patients with SSc, 51 patients with MCTD as well as 30 healthy control subjects were analyzed for lymphocyte subsets using flow cytometry. Of these patients, 19 had pulmonary involvement, including 9 patients with SSc and 10 patients with MCTD. Using directly the percentages from flow cytometry combined with internal standard beads calculated absolute number of peripheral lymphocyte subsets from the subjects in each group.

Results:

Although there were some changes among CD4+T cell subsets in PB from these SSc patients and MCTD patients, the major alteration was the reductions of Treg cells. Compared with the normal controls, the absolute number of CD4+CD25+FOXP3+Treg cells were significantly decreased in SSc patients and MCTD patients, and the absolute number of Th1 cells in MCTD patients is also significantly reduced. Notably, the absolute numbers of Th17 and Th2 cells were not different from those of normal controls, but the ratios of Th17/Treg in SSc patients and MCTD patients were significantly higher, causing by insufficient number of Treg cells (Fig 1). In addition, in patients with pulmonary involvement, we found that the absolute number of Treg cells was significantly reduced in patients with MCTD, while the absolute number of Th2 cells and Th17 cells was significantly reduced in patients with SSc(Fig 2).

Fig 1.

Comparison of the levels of CD4+T lymphocyte subsets in SSc patients, MCTD patients and healthy controls: (A) The absolute number of peripheral Th1 cells in patients with MCTD was significantly reduced; (B and C) There was no significant difference in the absolute number of Th2 cells in peripheral blood of different subjects; (D and E) The ratio of Th17/Treg cells in PB of patients with SSc and MCTD were significantly higher.*P< 0.05; **P< 0.01; ***P< 0.001.

Conclusion:

The number of peripheral Treg cells in patients with SSc and MCTD was significantly reduced, suggesting that that SSc and MCTD progression is associated with the imbalances between pro-inflammation cells to anti-inflammation Treg cells. In addition, we also found that the decrease in peripheral numbers of Treg cells may contribute to the development of MCTD-associated lung disease, whereas in SSc patients who had lung involvement, the reduce in peripheral number of Th17 cells may result in a severe imbalance of Th17/Treg cells, thereby promoting disease progression.

Fig 2.

Comparison of the levels of CD4+T lymphocyte subsets in patients who had pulmonary involvement and healthy controls: (A) There was no significant difference in the absolute number of Th1 cells in peripheral blood of different subjects; (B and C) The absolute number of peripheral Th2 cells and Th17 cells in patients with SSc were significantly reduced; (D and E) The ratio of Th17/Treg cells in PB of patients with MCTD were higher.*P< 0.05; **P< 0.01; ***P< 0.001.

References:

[1]Liu M, Wu W, Sun X, et al. New insights into CD4(+) T cell abnormalities in systemic sclerosis. Cytokine Growth Factor Rev. 2016 Apr; 28:31-6. doi: 10.1016/j.cytogfr.2015.12.002.

Acknowledgments:

None

Disclosure of Interests:

None declared

Krüppel homologue 1 interacts directly with Hairy and regulates ecdysis in the brown planthopper

Juvenile hormone (JH) plays important roles in the growth and development of insects. JH and its receptor methoprene-tolerant (Met) regulate the expression of transcription factors to control the transcription of downstream genes. The expression of Hairy (Hry) and Krüppel homologue 1 (Kr-h1) is regulated by JH and JH receptors. Hry and Kr-h1 are both crucial in mediating JH signalling. However, whether they interact at the gene level in regulating metamorphosis and whether they interact physically at the protein level remain unknown. We used co-immunoprecipitation, glutathione S-transferase pull-down and RNA interference (RNAi) approaches to study the genetic and biochemical interactions of the two proteins Hry and Kr-h1. The results showed that brown planthopper (Nilaparvata lugens) Hry and Kr-h1 interact directly: Hry binds to the N-terminal of Kr-h1, which includes five zinc-finger domains. The RNAi experiment showed that downregulation of Hry reduced the ratio of ecdysis failure caused by knockdown of Kr-h1, indicating that the downregulation of Hry might mitigate ecdysis failure via the downregulation of Kr-h1. The expression of Hry increased significantly when Kr-h1 was downregulated, whereas it did not change significantly when both were downregulated. Our results suggest that the binding of Hry protein with Kr-h1 prevents the N-terminal five zinc-finger domains from binding with DNA, which in turn inactivates the transcription activator or inhibitor function of Kr-h1. Hry could possibly be used as a target for pesticide applications in the future.

AB0936 CLINICAL STUDY ON PERIPHERAL BLOOD IMMUNE FUNCTION IN PATIENTS WITH GOUTY ARTHRITIS

Background:

Gout is an inflammatory disease characterized by hyperuricemia and recurrent arthritis. In severe cases, joint disability and renal insufficiency may occur[1]. In recent years, many studies have found that immune dysfunction plays an important role in the occurrence and development of gout[2]. Therefore, in-depth study of its internal mechanism is of great significance for the prevention and treatment of gout.

Objectives:

This paper mainly discussed the expression of peripheral blood immune function in patients with gouty arthritis and the changes and significance of peripheral blood immune function in gout with different uric acid levels.

Methods:

A retrospective analysis was performed on 258 outpatients and inpatients with gout in shanxi medical university from 2016 to 2019, all of which met the diagnostic criteria of the American college of rheumatology (ACR) in 1997, and 41 healthy controls. Complete clinical data and general laboratory data were collected, and peripheral blood lymphocyte and CD4+T cell counts were completed for all subjects.

Results:

(1) Total peripheral blood B cells of gout patients [238.00 (171.50,323.07) and 191.04 (149.66,253.14), Z=-2.759, P=0.006], Th cells [814.11 (617.50,1052.89) and 625.84 (562.52,750.15), Z=-3.905, P<0.001], Th/Ts [1.4 (1.04,2.00) and 1.11 (0.89,1.52), Z=-2.862,Th17/Treg [0.36 (0.20,0.60) and 0.24 (0.14,0.34), Z=-3.949, P=0.000] and the absolute counts of Th17 cells [9.06 (5.07,15.57) and 7.48 (4.31,10.18), Z=-2.520, P=0.012] were higher than those of the healthy control group, and the differences were statistically significant.The absolute count of Treg cells [28.82 (17.48,38.04) and 30.22 (22.74,39.46), Z=-2.249, P=0.025] was lower than that of the healthy control group, and the difference was statistically significant. (2) The Th17% [1.05 (0.71,1.42) and 1.27 (0.73,2.00), Z=-1.995, P=0.046] and the Th17/Treg [0.25 (0.14,0.44) and 0.39 (0.23,0.63), Z=-3.147, P=0.002] in peripheral blood of patients with high uric acid in the gout group were higher than those in the normal uric acid group, the difference was statistically significant. The Treg % [3.84 (2.65,5.02) and 3.12 (2.36,4.37), Z=-2.239, P=0.025], and the Treg cells [30.75 (21.97,43.27) and 24.07 (16.84,36.29), Z=-2.522, P=0.012] were lower than those in the uric acid control group, with statistically significant differences.

Conclusion:

The level of Th17 cells in peripheral blood of patients with gout increased significantly while the level of regulatory T cells decreased significantly. Th17 cell level in peripheral blood of the high uric acid group was significantly increased compared with the normal uric acid group, while the regulatory T cell level was also significantly decreased, and the Th17/Treg ratio was also increased. This suggests that regulatory T cells may play an important role in the pathogenesis of gout and are closely related to uric acid metabolism, so the study of internal mechanism can provide a new target for the treatment of gout.

References:

[1]Ragab G, Elshahaly M, et al. Gout: An old disease in new perspective - A review[J]. Adv Res. 2017;8(5):495–511. DOI: 10.1016/j.jare.2017.04.008.

[2]Dai XJ, Tao JH, et al. Changes of Treg/Th17 Ratio in Spleen of Acute Gouty Arthritis Rat Induced by MSU Crystals. [J]. Inflammation. 2018;41(5):1955-1964. Doi: 10.1007/s10753-018-0839-y.

Disclosure of Interests:

None declared

0638 Evaluation of an Oral Drug Pyridostigmine Bromide in Patients with Mild to Moderate Obstructive Sleep Apnea

Introduction

A randomized, double-blind, cross-over, placebo-controlled clinical study with pyridostigmine bromide (PYD) in obstructive sleep apnea (OSA) patients ranging from mild to moderate disease was conducted to evaluate its clinical efficacy and safety.

Methods

Six diagnosed male patients with averages of age 48 yr (38 - 57 yr), BMI 28 (26 - 33), AHI 19.2 (15 - 26.2), minimum oxygen saturation (Min SaO2) 81% (75 - 87%) were enrolled to the study. The study consisted one-night acclimatization period followed immediately by a 2-night double-blind treatment period when subjects received either a single dose of PYD (a cholinesterase inhibitor, 90 mg) or placebo before sleep. Subjects were required to maintain in a supine position, and monitored by a standard polysomnography all the time. Sleep questionnaires (The SMH Sleep Questionnaire and ESS) were taken daily immediately after sleep and at the evening to evaluate the sleep satisfaction and the day-time quality, respectively. Safety of the drug was monitored and evaluated.

Results

Reductions of AHI (28.1%, p &lt; 0.01), apnea index (37.2%, p &lt; 0.05), % of total apnea/hypopnea time (36.4%, p &lt; 0.05) were observed in the treatment group compared with the placebo between 2-7 hours of sleep. Min SaO2 was increased, no change, or decreased by PYD in 3, 2, or 1 subject(s), respectively. PYD was generally well tolerated with minimum minor incidents. Subjects reported to have more satisfied sleep and more clear-headed in the treatment night, and more energy, more concentrated and less sleepy during the daytime following the treatment night.

Conclusion

This study demonstrated the initial effectiveness of the PYD treatment for OSA, indicating that it may provide a new treatment option if the efficacy can be maintained in a large-scale clinical trial.

Support

N/A

Precision measurement of the neutral pion lifetime

The explicit breaking of the axial symmetry by quantum fluctuations gives rise to the so-called axial anomaly. This phenomenon is solely responsible for the decay of the neutral pion π⁰ into two photons (γγ), leading to its unusually short lifetime. We precisely measured the decay width Γ of the [Formula: see text] process. The differential cross sections for π⁰ photoproduction at forward angles were measured on two targets, carbon-12 and silicon-28, yielding [Formula: see text], where stat. denotes the statistical uncertainty and syst. the systematic uncertainty. We combined the results of this and an earlier experiment to generate a weighted average of [Formula: see text] Our final result has a total uncertainty of 1.50% and confirms the prediction based on the chiral anomaly in quantum chromodynamics.

NF-κB inhibitor QNZ protects human chondrocyte degeneration by promoting glucose uptake through Glut4 activation

OBJECTIVE

Glucose is not only an energy source but also raw material for proteoglycan biosynthesis of chondrocyte. The aim of the present study is to explore the role of QNZ in the progress of chondrocytes glucose uptake and investigate whether it will improve the chondrocytes degeneration through Glut4 activation.

PATIENTS AND METHODS

We isolated human chondrocytes from the cartilage by the patients who underwent total knee arthroplasty operations. Chondrocytes were pretreated with insulin or QNZ for 24 h. The uptake of glucose with stimulation, as well as the expression of Glut4, collagen II, aggrecan, MMP13, TNF-α, PCNA, and the p16 levels were determined by Western blot, quantitative reverse-transcription polymerase chain reaction (qPCR), or immunofluorescence.

RESULTS

Both insulin and QNZ stimuli to chondrocytes contributed to the expression of Glut4 and glucose uptake compared to the normal cells. Additionally, collagen II and aggrecan expression was detected to a significant increase, along with the reduced levels of MMP13 and TNF-α after exposed to QNZ. Moreover, QNZ protected chondrocytes degeneration via promoting proliferation and delaying aging. After blocking Glut4, the glucose uptake significantly reduced in QNZ treatment, as well as the expression of collagen II and aggrecan. However, no significant changes were noticed in the MMP13 and TNF-α levels.

CONCLUSIONS

The present study demonstrates that inhibition of NF-κB activation by QNZ would improve the glucose uptake through Glut4 activation, which plays an important role in the protection of chondrocytes degeneration.

Nonpharmaceutical Measures for Pandemic Influenza in Nonhealthcare Settings-Personal Protective and Environmental Measures

There were 3 influenza pandemics in the 20th century, and there has been 1 so far in the 21st century. Local, national, and international health authorities regularly update their plans for mitigating the next influenza pandemic in light of the latest available evidence on the effectiveness of various control measures in reducing transmission. Here, we review the evidence base on the effectiveness of nonpharmaceutical personal protective measures and environmental hygiene measures in nonhealthcare settings and discuss their potential inclusion in pandemic plans. Although mechanistic studies support the potential effect of hand hygiene or face masks, evidence from 14 randomized controlled trials of these measures did not support a substantial effect on transmission of laboratory-confirmed influenza. We similarly found limited evidence on the effectiveness of improved hygiene and environmental cleaning. We identified several major knowledge gaps requiring further research, most fundamentally an improved characterization of the modes of person-to-person transmission.

Nonpharmaceutical Measures for Pandemic Influenza in Nonhealthcare Settings-International Travel-Related Measures

International travel–related nonpharmaceutical interventions (NPIs), which can include traveler screening, travel restrictions, and border closures, often are included in national influenza pandemic preparedness plans. We performed systematic reviews to identify evidence for their effectiveness. We found 15 studies in total. Some studies reported that NPIs could delay the introduction of influenza virus. However, no available evidence indicated that screening of inbound travelers would have a substantial effect on preventing spread of pandemic influenza, and no studies examining exit screening were found. Some studies reported that travel restrictions could delay the start of local transmission and slow international spread, and 1 study indicated that small Pacific islands were able to prevent importation of pandemic influenza during 1918–19 through complete border closure. This limited evidence base indicates that international travel-related NPIs would have limited effectiveness in controlling pandemic influenza and that these measures require considerable resources to implement.

Nonpharmaceutical Measures for Pandemic Influenza in Nonhealthcare Settings-Social Distancing Measures

Influenza virus infections are believed to spread mostly by close contact in the community. Social distancing measures are essential components of the public health response to influenza pandemics. The objective of these mitigation measures is to reduce transmission, thereby delaying the epidemic peak, reducing the size of the epidemic peak, and spreading cases over a longer time to relieve pressure on the healthcare system. We conducted systematic reviews of the evidence base for effectiveness of multiple mitigation measures: isolating ill persons, contact tracing, quarantining exposed persons, school closures, workplace measures/closures, and avoiding crowding. Evidence supporting the effectiveness of these measures was obtained largely from observational studies and simulation studies. Voluntary isolation at home might be a more feasible social distancing measure, and pandemic plans should consider how to facilitate this measure. More drastic social distancing measures might be reserved for severe pandemics.

[Strengthening basic and clinical research on ocular infection caused by coronavirus]

This article was published ahead of print on the official website of Chinese Jounal of Ophthalmology on February 19, 2020. The prevention and treatment of coronavirus disease 2019 (COVID-2019) has reached the critical stage in China. Ocular surface represents a possible route for infection. Based on the previous studies and our own research, we summarize the potential transmission route and clinical symptoms of COVID-2019 in the eye, as well as the further prevention and research, with the expectation of contributing to the development in the field of infectious eye disease in China. (Chin J Ophthalmol, 2020, 56:250-252).

[Feasibility, safety and long-term efficacy of laparoscopic total gastrectomy combined with distal pancreaticosplenectomy for T4b gastric cancer]

Objective: To explore the feasibility, safety and long-term efficacy of laparoscopic total gastrectomy combined with distal pancreaticosplenectomy for the treatment of T4b gastric cancer. Methods: A retrospective cohort study was performed. Clinical data of consecutive patients with T4b gastric cancer invading pancreatic tail undergoing laparoscopic or open total gastrectomy combined with distal pancreaticosplenectomy from January 2010 to December 2014 were analyzed retrospectively. Enrollment criteria: (1) primary gastric cancer confirmed by pathology as T4b adenocarcinoma; (2) chest+abdominal+pelvic enhanced CT indicated cancer invading pancreatic tail without distant metastasis, and R0 resection was evaluated as feasible before operation; (3) physical status was ECOG score 0 to 2, and was tolerant to operation. Patients with peritoneal implant metastasis and tumor invasion of other organs during operation, or changes in surgical methods for other reasons were excluded. All the operations were performed by the same surgical team, which had the experiences of more than 100 cases of laparoscopic and 100 cases of open radical gastrectomy with D2 lymph node dissection. The choice of surgical procedure was discussed by the surgeon and the patient, and decided according to the patient's intension. Patients were divided into the laparoscopic group and open group according to the surgical method. Intraoperative and perioperative findings were compared between the two groups. The 3-year disease-free survival rate were analyzed with Kaplan-Meier survival curve and compared by using log-rank test. Results: A total of 37 consecutive patients were enrolled, including 21 in the laparoscopic group and 16 in the open group, and no one receiving laparoscopic procedure was converted to open surgery. The baseline data of two groups were comparable (all P>0.05). Compared with the open group, the laparoscopic group had significantly longer operation time [(264.0±35.1) minutes vs. (226.6±49.9) minutes, t=2.685, P=0.011], significantly less intraoperative blood loss [(65.7±37.4) ml vs. (182.2±94.6) ml, t=-4.658, P<0.001], significantly shorter time to postoperative flatus [(2.8±0.7) days vs. (4.1±0.7) days, t=-5.776, P<0.001] and significantly shorter postoperative hospital stay [(13.3±2.8) days vs. (16.6±4.3) days, t=-2.822, P=0.008]. Morbidity of postoperative complications, including anastomotic leakage, pancreatic fistula, abdominal abscess, intraperitoneal hemorrhage and duodenal stump leakage, in two groups was similar [19.0% (4/21) vs. 4/16, P=0.705]. There were no cases of anastomotic bleeding or stenosis. The 30-day postoperative mortality was 0 in the laparoscopic group and 1/16 in the open group, respectively (P=0.432). The 3-year disease-free survival rates were 38.1% and 37.5% in the laparoscopic and open group, respectively (P=0.751). Conclusion: Laparoscopic total gastrectomy combined with distal pancreaticosplenectomy performed by experienced surgeons for T4b gastric cancer is safe and effective.

[Monomorphic epitheliotropic intestinal T-cell lymphoma: a clinicopathological analysis of twelve cases]

Objective: To investigate the clinicopathological features, diagnosis and differential diagnosis of monomorphic epitheliotropic intestinal T-cell lymphoma (MEITL). Methods: A total of 12 specimens were collected, which were surgically resected and verified as MEITL by postoperative pathology, immumohistochemical staining and gene rearrangement at the First Affiliated Hospital of Nanjing Medical University from 2012 to 2018, and all of these had complete clinical and pathological data. The MEITL cases were reviewed to compare the clinicopathological characteristics, including morphologic and immunophenotypic features and followed up by telephone and clinic visit. Results: All the cases were diagnosed with MEITL. There were 8 males and 4 females. Male to female ratio was 2∶1, at a median age of 54 years. The sites of involvement included jejunum (4 cases), ileum (5 cases), duodenum (1 case), ileocecal junction (1 case) and rectum (1 case). The neoplastic cells were monotonous of small to intermediate cells in size with round to slightly irregular nuclei in 11 cases. The immunophenotyping showed that CD3 (12/12), CD8 (11/12), CD43 (11/12), CD56 (11/12), TIA-1 (12/12) were positive; CD5 (12/12), Gran B (9/12), and perforin (7/12) were negative. Two cases aberrantly expressed the B-cell marker CD20. A high proliferation index was demonstrated by Ki-67 immunostaining. In situ hybridization for EBER was all negative(12/12). The whole exome sequencing(WES) mutational landscape of MEITL was remarkably homogeneous, showing significantly enriched clusters among histone modifier genes, JAK-STAT and MAPK-signal pathways. Histonelysine N-methytransferase SETD2 gene was mutated in 2/4 tumors. All the patients analyzed harbored at least one mutation in the JAK-STAT signal pathway, including STAT5B (2/4), JAK3 (3/4) and STAT5A (2/4). Furthermore, frequent alterations (TP53) were observed in the MAPK pathway in 3/4 of MEITL cases. The CNV analysis derived from WES data identified multiple regions of frequent gains and losses. In particular, gains in 1q, 7q and 9q, and recurrent losses involving 7p and 8p were observed. Conclusions: MEITL is a rare and aggressive type of extranodal T-cell lymphoma. The differential diagnosis of MEITL includes EATL, extranodal NT/T-cell lymphoma and other types of PTCL. Diagnosis should be correlated to clinical symptoms while the final diagnosis is mainly based on the pathological features, immunophenotypes and genetic testing.

[A sequential conditional mean model for assessing total effects of exposure in longitudinal data]

In prospective cohort study, multi follow up is often necessary for study subjects, and the observed values are correlated with each other, usually resulting in time-dependent confounding. In this case, the data generally do not meet the application conditions of traditional multivariate regression analysis. Sequential conditional mean model (SCMM) is a new approach that can deal with time-dependent confounding. This paper mainly summarizes the basic theory, steps and characteristics of SCMM.