CircVCAN regulates the proliferation and apoptosis of osteoarthritis chondrocyte through NF-κB signaling pathway

OBJECTIVE

Osteoarthritis is one of the chronic diseases with a high incidence. CircRNA is a circular non-coding RNA. Studies show that CircRNA is closely relevant to the pathogenesis of OA chondrocytes. However, the specific principle is still unclear.

PATIENTS AND METHODS

38 patients with OA tissues and 38 patients with normal knee cartilage in our hospital were selected, respectively. The mRNA expression levels of CircVCAN were measured by quantificational real-time polymerase chain reaction (qRT-PCR). Cell proliferation was detected by the Cell Counting Kit (CCK8). Cell cycle and apoptosis of OA chondrocytes were measured by flow cytometry. qRT-PCR and western blot were used to detect PCNA, p50, p52, p65 mRNA and protein expression levels.

RESULTS

CircVCAN was highly expressed in OA tissues and OA chondrocytes. Cell proliferation and PCNA expression levels decreased significantly after transfection with si-CircVCAN in OA-chondrocytes. However, there was a significant increase on OA chondrocytes after transfection with LV-CircVCAN. Compared with the si-NC group, the apoptosis rate of OA chondrocytes was significantly increased after transfection with si-CircVCAN. The proportion of G0/G1 phase in the cell cycle was significantly reduced and the proportion of S phase was significantly increased. On the contrary, the apoptosis rate was significantly reduced after transfection with LV-CircVCAN. The proportion of G0/G1 phase in the cell cycle was significantly increased and the proportion of S phase was significantly reduced. The mRNA and protein levels of p50, p52 and p65 were significantly increased after transfection of LV-CircVCAN in OA-chondrocytes. Furthermore, PDTC (NF-κB inhibitor) transfection can significantly reverse the effect of overexpression of CircVCAN on the proliferation and apoptosis of OA chondrocytes.

CONCLUSIONS

CircVCAN is overexpressed in OA tissues and cells. CircVCAN can affect the proliferation and apoptosis of OA chondrocytes by blocking the activation of the NF-κB signaling pathway. Thus, CircVCAN may be an important target molecule for OA treatment.

CORRELATION BETWEEN SUBCLINICAL HYPOTHYROIDISM AND DYSLIPIDEMIA IN WOMEN IN NORTHEAST CHINA

CONTEXT

It is well known that thyroid hormones are important, being involved in affects the metabolism of carbohydrate, protein, lipids. The relationship between thyroid hormones and lipid metabolism is the focus of recent research.

OBJECTIVE

To investigate the relationship between subclinical hypothyroidism and lipid metabolism in women.

DESIGN

We conducted an epidemiological survey of thyroid diseases among women in Northeast China from September 2014 to December 2014.

SUBJECTS AND METHODS

A total of 1397 women underwent physical examinations and laboratory tests for thyroid function and lipid metabolism.

RESULTS

We found that the detection rate of subclinical hypothyroidism was 13.03%. Patients with subclinical hypothyroidism showed significantly higher levels of triglyceride (1.69±1.9 vs. 1.45±1.4) and the risk of hyper triglyceridemia in women with thyroid stimulating hormone (TSH) levels ≥10mIU/L was 4.96-fold higher compared with that in the normal population (P<0.01).

CONCLUSION

Disorders of lipid metabolism in women with subclinical hypothyroidism show a direct correlation with the level of TSH, and the risk of hyper triglyceridemia is significantly increased when the level of TSH ≥10mIU/L.

FAM96A knock-out promotes alternative macrophage polarization and protects mice against sepsis

Sepsis is an intractable clinical syndrome characterized by organ dysfunction when the body over-responds to an infection. Sepsis has a high fatality rate and lacks effective treatment. Family with sequence similarity 96 member A (FAM96A) is an evolutionarily conserved protein with high expression in the immune system and is related to cytosolic iron assembly and tumour suppression; however, research has been rarely conducted on its immune functions. Our study found that Fam96a-/- mice significantly resisted lesions during sepsis simulated by caecal ligation and puncture (CLP) or endotoxicosis models. After a challenge with lipopolysaccharide (LPS) or infection, Fam96a-/- mice exhibited less organ damage, longer survival and better bacterial clearance with decreased levels of proinflammatory cytokines. While screening several subsets of immune cells, FAM96A-expressing macrophages as the key cell type inhibited sepsis development. In-vivo macrophage depletion or adoptive transfer experiments abrogated significant differences in the survival of sepsis between Fam96a-/- and wild-type mice. Results of the bone marrow-derived macrophage (BMDM) polarization experiment indicated that FAM96A deficiency promotes the transformation of uncommitted monocytes/macrophages (M0) into M2 macrophages, secreting fewer proinflammatory cytokines. FAM96A may mediate an immunometabolism shift - from oxidative phosphorylation (OXPHOS) to glycolysis - in macrophages during sepsis, mirrored by reactive oxygen species (ROS) and glucose uptake. These data demonstrate that FAM96A regulates inflammatory response and provide a novel genomic insight for sepsis treatment.

Effect of front-of-package nutrition labeling on food purchases: a systematic review

OBJECTIVES

This study systematically reviewed evidence from interventions on the effect of front-of-package (FOP) nutrition labeling on food purchases.

STUDY DESIGN

The study design used in this study is a systematic review.

METHODS

Keyword search was performed in PubMed, Web of Science, Scopus, and Cochrane Library.

RESULTS

Fifteen studies (10 randomized controlled trials, four pre-post studies, and one case-control study) met the eligibility criteria and were included in the review. Five studies were conducted in a controlled setting through the establishment of an online virtual supermarket or physical laboratory food store solely for the intervention. In contrast, the remaining ten studies were conducted in a naturalistic setting where people commonly purchase foods (e.g., supermarket, grocery store, school/hospital cafeteria, or vending machine). FOP labels assessed included traffic lights, health star rating, daily intake guides, health warnings, and high sugar symbol labels. Compared with the control, FOP labels were effective for helping participants make healthier food purchase decisions in five of the 12 studies that assessed traffic lights labels, in one of the two studies that assessed health warning labels, and in one study that assessed high sugar symbol labels. Three assessed health star ratings and one assessed daily intake guide labels, but none revealed an effect on food purchases compared with the control.

CONCLUSIONS

Findings on the effectiveness of FOP nutrition labels in 'nudging' consumers toward healthier food purchases remain mixed and inconclusive. Future studies should examine other types of FOP labels beside the traffic lights labels and explore the different effects by consumer affordability, population subgroup, and shopping environment.

[Characteristics and predictors of postoperative outcome of Crohn disease patients requiring abdominal surgery: a series of 1 048 cases from a single inflammatory bowel disease centre]

Objective: To examine the clinical characteristics, the potential relative factors for postoperative abdominal septic complications, and prognosis factors of surgical recurrence of Crohn disease (CD) patients after the first surgery. Methods: All the CD patients from Department of General Surgery, Jinling Hospital, Medical School of Nanjing University who had undergone at least one abdominal surgery from January 2007 to December 2017 were included for retrospective analysis. Hospital records were reviewed for information on clinical characteristics. Relative factors of postoperative abdominal septic complications were accessed by Logistic regression models, and prognosis factors of surgical recurrence were accessed by Cox proportional hazards regression models. Results: There were 1 048 patients included (733 males and 315 females), accounting for 1 513 operations. The age was 31(17) years and the length of resected small bowel was 30.0(40.0) cm at the first resection, 20.0(35.0) cm at the second resection, and 20.0(23.5) cm at the third resection. The length of resected small bowel was 25.0(40.0) cm at any resection. At the first abdominal surgery, 70.99%(744/1 048) patients were aged between 17 and 40 years, 66.98%(702/1 048) patients had ileocolonic disease, and 60.40%(633/1 048) patients had penetrating behavior. Penetrating behavior (OR=8.594, 95%CI: 3.397 to 21.740, P<0.01) and current smoking status (OR=2.671, 95%CI: 1.044 to 6.832, P=0.040) were significantly associated with an increased risk of postoperative septic complications, whereas staged operation (OR=0.360, 95%CI: 0.184 to 0.707, P=0.003) was associated with a decreased risk. Male gender (HR=1.500, 95%CI: 1.128 to 1.995, P=0.005), upper gastrointestinal disease (HR=1.526, 95%CI: 1.033 to 2.255, P=0.034), penetrating behavior (HR=1.506, 95%CI: 1.132 to 2.003, P=0.005) and emergency surgery (HR=1.812, 95%CI: 1.375 to 2.387, P<0.01) were significantly associated with an increased risk of postoperative surgical recurrence, whereas staged operation (HR=0.361, 95%CI: 0.227 to 0.574, P<0.01) was significantly associated with a decreased risk. Conclusions: In this cohort of CD patients receiving abdominal surgery from an inflammatory bowel disease center, the median age was 31 years and the median length of resected small bowel was 30 cm, at first resection. Patients who have risk factors of adverse postoperative outcome may be benefited from staged surgical approach.

Comorbid Depressive Symptoms, Visual Impairment, and Sarcopenia among Middle-Aged and Older Women: Findings from the West China Health and Aging Trend study

Previous reports have described close relationships between sarcopenia and either visual impairment or depression, but there have been few analyses investigating the association between sarcopenia and the coexistence of both visual impairment and depression. Herein, we sought to explore the associations between sarcopenia and comorbid depressive symptoms and visual impairment among older females. A cross-sectional analysis of females between the ages of 50 and 95 (n = 2454) from the West China Health and Aging Trend (WCHAT) study was conducted. Patient muscle mass was assessed via a bioimpedance-based approach using an InBody 770 device, while muscle strength was estimated based on handgrip strength as quantified with a digital grip strength dynamometer. Depressive systems were evaluated with the 15-item Geriatric Depression Scale (GDS-15), and a questionnaire was employed to evaluate patient visual functionality. Associations between sarcopenia and comorbid depressive status and visual impairment were explored through logistic regression analyses. Comorbid depressive symptoms and visual impairment were observed in 6.2% of the women included in this study, while 18.9% suffered from sarcopenia. Following adjustment for covariates, relative to normal controls, study subjects with only depression (OR=1.45, 95%CI=1.04-2.02), only visual impairment (OR=1.69, 95%CI=1.27-2.26), or comorbid depression and visual impairment (OR=1.76, 95% CI=1.16-2.67) exhibited a higher risk of sarcopenia. These results suggest that comorbid depression and visual impairment are linked to the prevalence of sarcopenia in older Chinese women. As such, further efforts to screen older women for these two comorbid conditions may thus be necessary.

Structure and thermal properties of beeswax-based oleogels with different types of vegetable oil

Beeswax-based oleogels with different types of vegetable oil, including camellia oil (CO), soybean oil (SO), sunflower oil (SFO), or flaxseed oil (FO), were prepared and their structure and thermal properties were evaluated. The critical concentration of oleogel obtained from each of CO, SO, and SFO at 25 °C was 3% (w/w), and that from FO was 4%. Thermal measurements revealed similar thermodynamic curves for oleogels in different lipid phases. X-Ray diffraction showed orthorhombic perpendicular subcell packing and characteristic peaks of the β’ form. Furthermore, a morphology analysis of the crystals showed that they were needle shaped. Fourier transform-infrared spectra revealed that beeswax-based oleogels were formed via non-covalent bonds and may be stabilized with physical entanglements. The oleogels showed oil type-dependent oxidative abilities, but they were all stable and showed no obvious changes in peroxide value during 90 days of storage at 5 °C.

Long non-coding RNA MIR503HG serves as a tumor suppressor in non-small cell lung cancer mediated by wnt1

OBJECTIVE

The incidence and death rate of lung cancer has been rising year by year. Non-small cell lung cancer (NSCLC) seriously affects people's health and quality of life. This study was designed to explore the functional role of long-chain non-coding RNA (LncRNA) MIR503HG in the development of NSCLC.

PATIENTS AND METHODS

The quantitative Real Time-Polymerase Chain Reaction (qRT-PCR) assay was conducted to access the expression level of MIR503HG in NSCLC cell lines and tissues. The Cell Counting Kit-8 (CCK-8) assay, colony formation assay, and flow cytometric analysis were performed to assess the ability of MIR503HG in regulating cell proliferation and apoptosis in NSCLC. Subsequently, Western blotting was used to detect the expression level of Wnt1 in NSCLC. Besides, in vivo tumorigenesis assay was performed in nude mice to examine the ability of MIR503HG in tumor formation.

RESULTS

MIR503HG was downregulated in NSCLC. CCK-8 assay and colony formation assay revealed that MIR503HG negatively regulated cell proliferation in NSLCL progression. In addition, MIR503HG promoted cell apoptosis and suppressed cell cycle progression in NSCLC in vitro. MIR503HG inhibited tumor formation in nude mice bearing NSCLC in vivo. MIR503HG downregulated Wnt1 expression in NSCLC.

CONCLUSIONS

Lon non-coding RNA MIR503HG was downregulated in NSCLC. The over-expression of MIR503HG suppressed cell proliferation and promoted cell apoptosis in vitro and repressed tumorigenesis in vivo. MIR503HG suppressed NSCLC progression via negatively regulating Wnt1 expression.

[The role of time-series propagation map and activity path of confirmed cases in the analysis and determination of COVID-19 epidemic]

Objective: The time sequence transmission map and the cases travel track were used to explain the chain of transmission, describe the characteristics of transmission and analyze the mode of epidemic of novel coronavirus pneumonia, so as to provide evidence for the relevant government departments to carry out epidemic prevention and control. Methods: The time sequence transmission map and the cases travel track table were drawn, according to the time of incidence, age, sex, number of close contacts and their interrelations. Results: At the end of February 10, 2020, 63 COVID-19 cases were reported in the research area. Among them, 57 cases were confirmed (1 deaths) and 6 cases were asymptomatic, 57 cases were imported cases (90.48%), 36 cases were reported by cluster epidemic (57.14%) among friends and relatives. Cases have been spread to the fourth generation. Conclusion: The time sequence transmission map and the cases travel track showed that, in the research area, the epidemic situation of COVID-19 was mainly caused by imported case, and the clustering transmission was the major spread model. The time sequence transmission map and the cases travel track are worth popularizing in the prevention and control of major infectious diseases.

Comparing nanoparticle polymeric micellar paclitaxel and solvent-based paclitaxel as first-line treatment of advanced non-small-cell lung cancer: an open-label, randomized, multicenter, phase III trial

BACKGROUND

Polymeric micellar paclitaxel (pm-Pac) is a novel Cremophor EL-free, nanoparticle micellar formulation of paclitaxel. We aimed to compare the efficacy and safety between pm-Pac plus cisplatin and solvent-based paclitaxel (sb-Pac) plus cisplatin in advanced non-small-cell lung cancer (NSCLC).

PATIENTS AND METHODS

A total of 448 stage IIIB to IV NSCLC patients were randomly assigned (2:1) to receive six 3-week cycles of either pm-Pac (230 mg/m²) plus cisplatin (70 mg/m²; n = 300), followed by dose escalation of pm-Pac to 300 mg/m² from the second 3-week cycle if prespecified toxic effects were not observed after the first cycle, or sb-Pac (175 mg/m²) plus cisplatin (70 mg/m²; n = 148). The primary end point was objective response rate (ORR) assessed by independent review committees (IRCs). The secondary end points included IRC-assessed progression-free survival (PFS), overall survival (OS), and safety.

RESULTS

Patients in the pm-Pac-plus-cisplatin group showed significant improvements in IRC-assessed ORR compared with those in the sb-Pac-plus-cisplatin group (50% versus 26%; rate ratio 1.91; P < 0.0001). Additionally, subgroup analysis showed that a higher ORR was consistently observed in both squamous and nonsquamous histological types. IRC-assessed median PFS was significantly higher in the pm-Pac-plus-cisplatin group than in the sb-Pac-plus-cisplatin group (6.4-month versus 5.3-month; hazard ratio 0.63; P = 0.0001). Median OS was not significantly different between the two groups. The incidence of treatment-related serious adverse events (9% versus 18%; P = 0.0090) was significantly lower in the pm-Pac-plus-cisplatin group than in the sb-Pac-plus-cisplatin group.

CONCLUSION

Pm-Pac plus cisplatin yielded superior ORR and PFS along with a favorable safety profile and should become an option for patients with advanced NSCLC.

CLINICAL TRIAL IDENTIFIER

ClinicalTrials.gov NCT02667743; https://clinicaltrials.gov/ct2/show/NCT02667743.

Upregulated miRNA-1236-3p in osteosarcoma inhibits cell proliferation and induces apoptosis via targeting KLF8

OBJECTIVE

To elucidate the regulatory effect of miRNA-1236-3p on the cellular behaviors of osteosarcoma (OS) cells, and to provide novel hallmarks and therapeutic targets for the diagnosis, treatment, and prognosis of OS.

PATIENTS AND METHODS

Relative level of miRNA-1236-3p in OS tissues and cell lines was determined by quantitative Real Time-Polymerase Chain Reaction (qRT-PCR). Regulatory effects of miRNA-1236-3p on the proliferative ability of HOS and U-2OS cells were evaluated by cell counting kit-8 (CCK-8) assay. Through flow cytometry, the potential influences of miRNA-1236-3p on cell cycle progression and apoptosis of OS cells were examined. Subsequently, the dual-luciferase reporter gene assay was conducted to explore the binding of KLF8 (Krüppel-like factor 8) to miRNA-1236-3p. Regulatory effects of KLF8 on cellular behaviors of OC cells were also evaluated.

RESULTS

MiRNA-1236-3p was downregulated in OS tissues relative to controls. Meanwhile, miRNA-1236-3p was lowly expressed in OS with worse TNM stage or distant metastasis. The overexpression of miRNA-1236-3p in HOS and U-2OS cells suppressed the proliferative ability, arrested the cell cycle in the G0/G1 phase and induced apoptosis. Conversely, miRNA-1236-3p knockdown obtained the opposite trends. KLF8 was verified to bind to miRNA-1236-3p, and its expression was negatively regulated by miRNA-1236-3p in OS cells. A series of functional experiments displayed the oncogenic role of KLF8 in OS.

CONCLUSIONS

MiRNA-1236-3p is downregulated in OS tissues and cell lines. The overexpression of miRNA-1236-3p suppresses the proliferative ability and induces apoptosis of OS cells via downregulating KLF8.

Long noncoding RNA DDX11-AS1 induced by YY1 accelerates colorectal cancer progression through targeting miR-873/CLDN7 axis

OBJECTIVE

Increasing studies have confirmed long non-coding RNAs (lncRNAs) as novel regulators in tumorigenesis. LncRNA DDX11 antisense RNA 1 (DDX11-AS1) has been found to be abnormally expressed in several tumors. In this work, we aimed to evaluate its expressions and functions in colorectal cancer (CRC).

PATIENTS AND METHODS

The Cancer Genome Atlas (TCGA) datasets were used for the identification of dysregulated lncRNA in CRC. The levels of DDX11-AS1 were determined in tumor tissues and cell lines by Real Time-Polymerase Chain Reaction (RT-PCR). The clinical significance of DDX11-AS1 in CRC patients was analyzed using Chi-square test and Kaplan-Meier analysis. Functional assays for the exploration of DDX11-AS1 and miR-873 were performed using a series of cells experiment. ChIP assay and luciferase reporter assays were used to explore the mechanism of actions of DDX11-AS1 in CRC cells.

RESULTS

We identified DDX11-AS1 as a new CRC-related lncRNA whose levels were distinctly up-regulated in CRC specimens and cell lines, partly induced by YY1. Clinical explorations suggested that increased expressions of DDX11-AS1 in CRC were positively associated with lymph nodes metastasis and TNM stage and had a distinct influence on the overall survival. Further multivariate assays indicated that DDX11-AS1 was an independent prognostic parameter implying a poorer clinical outcome for patients with CRC. Functional assays revealed that the knockdown of DDX11-AS1 suppressed the proliferation, migration, and invasion of CRC cells, and stimulate apoptosis. Mechanistic studies showed that the up-regulation of DDX11-AS1 competitively bound to miR-873 prevented CLDN7 from miRNAs-mediated degradations, thus facilitated the CRC progress. Further rescue assays were carried out to achieve confirmation.

CONCLUSIONS

Our present findings may enhance our understanding of the pathogenesis of CRC and revealed DDX11-AS11 as a potential therapeutic target for CRC.

[Abnormal expression of WWP1 in chronic lymphocytic leukemia and its clinical significance]

Objective: This study aims to investigate the expression of E3 ubiquitin-ligase (WWP1) in chronic lymphocytic leukemia (CLL) patients and analyze its correlation with clinical prognostic indicators (TP53, CD38, IGHV mutation) and its prognostic value. Methods: A total of 48 CLL patients and 9 age-matched normal subjects were enrolled in the study. The WWP1 expression was detected by SYBR Green-based real-time PCR, and the clinical relationship was analyzed by GraphPad Prism software. Results: The WWP1 median expression was 0.007 (95% CI 0.005-0.010) in the normal control group and 0.031 (95% CI 0.019-0.044) in the CLL group (P<0.001) . A sub-groups analysis implicated a statistically significant result (P=0.022) , showing that the median time from a relatively high and low transcription level of WWP1 to the first treatment was 24 months and 35 months, respectively. Positive CD38 and ZAP-70 expressions were associated with a higher WWP1 expression (P=0.012 and 0.029, respectively) . Conclusion: An abnormal WWP1 mRNA expression was found in CLL patients with significant correlation with ZAP-70 and CD38 expressions, and WWP1 may become a new supplement of CLL prognostic markers.

["Point line anterograde dissection" for the safe preparation of supraclavicular flap]

Objective: To investigate the application in the preparation of supraclavicular island flap by "point line anterograde dissection (PLAD) ". Methods: A retrospective analysis was performed on 45 flaps of 43 patients treated with supraclavicular artery island flap from the Department of Otorhinolaryngology Head and Neck Surgery, Beijing Tongren Hospital Affiliated to Capital Medical University from January 2013 to June 2019. The patients were all male, aged 35-72 years old. There were 26 cases of hypopharyngeal cancer, 4 cases of recurrent laryngeal cancer, 2 cases of cervical esophageal cancer, 1 case of tonsillar cancer, 1 case of parotid gland cancer, 3 cases of postoperative pharyngeal fistula after hypopharyngeal cancer, 2 cases of esophageal fistula after trauma, 2 cases of esophageal stricture after hypopharyngeal carcinoma operation, 1 case of autoimmune laryngeal stenosis, and 1 case of cheek defect after maxillary sinus cancer operation."Point" was the origin of the supraclavicular artery in the transverse carotid artery. "Line" was an extension line made along the starting point of the supraclavicular vessel for anterograde anatomy of 1-2 cm and the direction of the blood vessel. The extension line was used as the central axis of the designed island flap. Characteristics of flap blood supply, the time of flap preparation, flap survival, donor area recovery and clinical follow-up were recorded. Results: The arterial blood supply of the flap was constant, and the venous reflux was variable. The area of the prepared flap was (4-8) cm×(10-18) cm, and the preparation time was 30-60 min, with a median of 42 min. Skin flap survival rate was 100%. Partial necrosis of skin flap occurred in 1 patient and postoperative pharyngeal fistula occurred in 5 patients, all of whom were cured by dressing change. The donor site defects were closed and sutured directly. 3 patients had partial incision dehiscence and healed after dressing change. During the follow-up, 1 patient was lost, and the remaining 42 patients were followed up for 8 to 55 months.40 patients involved swallowing function, all of them returned to regular diet or soft fluid after operation.40 patients involved malignant tumors and local tumor recurrence in 3 patients among whom, there were 2 cases of lymph node recurrence, and 2 cases of distant metastasis, including 1 case of lung metastasis and 1 case of bone metastasis. Conclusion: PLAD is a simple, safe and efficient method for the preparation of supraclavicular island flap.

[A preliminary study on the evaluation of diaphragm function by ultrasound in patients with invasive mechanical ventilation]

Objectives: To study the feasibility of using ultrasound to evaluate diaphragm function in patients with invasive mechanical ventilation. Methods: From March to December 2017, 40 adult patients with acute respiratory distress syndrome who were admitted to the Department of Critical Care Medicine, Xiangya Hospital, Central South University for more than 48 hours were included. Diaphragmatic excursion and thickness of bilateral anterior, middle and posterior parts were measured by ultrasound for 5 consecutive days. Results: (1) Compared with the diaphragmatic excursion of the right [anterior: (11.05±3.04) mm; middle: (12.08±2.71) mm; posterior: (11.51±3.33) mm] and left [anterior: (13.63±7.52) mm; middle: (15.44±7.52) mm; posterior: (14.76±6.93) mm] sides on day 1, the diaphragmatic excursion of the right [anterior: (8.90±3.65) mm; middle: (10.02±4.24) mm; posterior: (10.25±4.38) mm] and left [anterior: (9.82±1.96) mm; middle: (11.60±1.13) mm; posterior: (11.52±1.98) mm] sides decreased significantly on day 3 (P<0.05). Bilateral anterior, middle and posterior diaphragmatic excursion recovered on day 5, and was higher than the baseline levels on day 1, with the left middle and posterior diaphragmatic excursion changing most significantly. (2) Compared with day 1, 2, 3, the thickening fraction of bilateral anterior, middle and posterior diaphragm were significantly decreased on day 4, with the left middle part [day 1: (33.87±14.34)%; day 2: (37.26±13.91)%; day 3: (30.56±14.27)%; day 4: (15.53±5.68)%] and the left posterior part [day 1: (35.50±15.69)%; day 2: (39.84±15.32)%; day 3: (29.06±14.96)%; day 4: (13.30±5.79)%] changing most significantly (P<0.05). The thickening fractions of left anterior, middle and posterior diaphragm recovered on day 5 compared with that on day 4, but still lower than those on day 1 (P<0.05). Conclusions: It is feasible to evaluate the diaphragm function in patients with invasive mechanical ventilation by ultrasound, which can provide guidance for preventing diaphragmatic atrophy and withdrawing from mechanical ventilation.

[Typical case analysis of COVID-19 cluster epidemic in Shaanxi, 2020]

Objective: By analyzed the transmission patterns of 4 out of the 51 COVID-19 cluster cases in Shaanxi province to provide evidences for the COVID-19 control and prevention. Methods: The epidemiological data of RT-PCR test-confirmed COVID-19 cases were collected. Transmission chain was drawn and the transmission process was analyzed. Results: Cluster case 1 contained 13 cases and was caused by a family of 5 who traveled by car to Wuhan and returned to Shaanxi. Cluster case 2 had 5cases and caused by initial patient who participated family get-together right after back from Wuhan while under incubation period. Cluster case 3 contained 10 cases and could be defined as nosocomial infection. Cluster case 4 contained 4 cases and occurred in work place. Conclusion: Higher contact frequency and smaller places were more likely to cause a small-scale COVID-19 cluster outbreak, with potential longer incubation period. COVID-19 control strategies should turn the attention to infection prevention and control in crowded places, management of enterprise resumption and prevention of nosocomial infection.