[Feasibility of near-infrared fluorescence imaging in assisting with the determination of the resection range of radiation intestinal injury]

Objective: To investigate the feasibility of near-infrared fluorescence imaging (NIRFI) to assist in determining the resection range of radiation intestinal injury (RII). Methods: A descriptive cohort study was conducted. Clinical data of 10 RII patients who presented intestinal obstruction and received operation with more than 100 cm of small intestine had been resected atGeneral Department of Jinling Hospital from October 2014 to January 2015 were retrospectively analyzed. The Novadaq SPY Intra-operative Imaging System was used in capturing and viewing fluorescent images. Firstly, the dense adhesion was mobilized and the obstructive intestine was fully freed under laparoscopy, then entering into abdomen from the corresponding incision. The surgeon determined the resection range according to the color of the intestinal serous layer of the diseased intestinal wall, the thickness of the intestinal wall, and the degree of swelling of the mesentery. Afterwards, intra-operative NIRFI was performed by intravenous injection of 2 ml indocyanine green (ICG) and the imaging results of the diseased intestinal arteriovenous phase were observed and recorded. The evaluation criteria for the final resection range were mainly based on the changes in mesenteric arterial phase imaging. In RII lesions, mesenteric vessels in mesenteric artery phase were disordered, and the comb-like distribution of normal mesenteric vessels completely disappeared. Only the clouded appearance in the intestinal wall was observed. Imaging results of the diseased intestinal tissue during the development phase and mesenteric vein phase were not significantly different from normal intestinal tissue. Intraoperative and postoperative conditions under NIRFI-assisted positioning, including the resection range, anastomosis site, operation-related complications, hospitalization time and cost were recorded. Data of abdominal contrast-enhanced CT and gastrointestinal angiography during 5 years of follow-up were collected to evaluate whether there was anastomotic stenosis or insufficient resection of diseased bowel. Results: Based on the imaging of mesenteric arterial phase of NIRFI, the median resection length of the small intestine was 185 (120-260) cm. After NIRFI imaging, only local lesion of ileum was excised in 6 patients, and jejunum-ileum anastomosis was performed to preserve ileocecal flap. No serious complications such as anastomotic leakage and anastomotic hemorrhage, or chronic intestinal failure such as short bowel syndrome occurred. The median hospitalization time was 32 (22-51) days, and the median hospitalization cost was 142 000 (90 000-175 000) RMB. The hospitalization time and cost were mainly used for the enteral and parenteral nutrition support treatment during the perioperative period. All the patients had normal oral diet and/or oral enteral nutrient. After 5 years of follow-up, no recurrence was found. Abdominal contrast-enhanced CT and gastrointestinal angiography showed no thickening of the intestinal wall or stenosis of the lumen. Conclusion: Mesenteric arterial phase imagingof NIRFI can help surgeons to determine the site and range of resection of RII lesions.

[Challenges and countermeasures of schistosomiasis control in Hunan Province in the new era]

This paper describes the current epidemic characteristics and endemic status of schistosomiasis, analyzes the main challenges of schistosomiasis control and proposes the emphasis and interventions for future schistosomiasis control activities in Hunan Province, so as to provide insights into the elimination of schistosomiasis in Hunan Province.

[Implications, spiritual characteristics and practical significance of Chinese schistosomiasis control culture]

The culture of schistosomiasis control is specific in the history of Chinese culture. Broadly speaking, the culture of schistosomiasis control is a summary of specific social mood, social consciousness and material culture created by Chinese populations during the progress of schistosomiasis control since the founding of the People's Republic of China. Narrowly speaking, the culture of schistosomiasis control is the spiritual culture that is jointly created and nurtured by schistosomiasis control workers since the founding of the People's Republic of China. The spiritual features of Chinese schistosomiasis control culture are characterized by the patriotism and care about the people, the matter-to-fact attitude, the pioneering and enterprising spirit, and the spirit of sacrifice and dedication. The ultimate goal of the research on the culture of schistosomiasis control is to facilitate the achievement of the strategic goal of Healthy China 2030 as scheduled, accelerate the progress towards elimination of schistosomiasis, and to promote the sustainable development of schistosomiasis control in China.

[Effects of dendritic epidermal T cells on proliferation and apoptosis of epidermal cells in wound margin of mice]

Objective: To explore the effects of dendritic epidermal T cells (DETC) on proliferation and apoptosis of epidermal cells in wound margin of mice and its effects on wound healing. Methods: Twenty-eight healthy specific pathogen free (SPF) C57BL/6 wild-type (WT) male mice aged 8-12 weeks and 60 SPF T lymphocyte receptor δ-knockout (TCR δ(-/-)) male mice aged 8-12 weeks were selected to conduct the following experiments. (1) Eight WT mice were selected to isolate epidermal cells and primarily culture DETC according to the random number table. Morphological observation and purity identification of DETC by flow cytometer were detected immediately after culture and on culture day (CD) 15 and 30, respectively. (2) According to the random number table, 5 WT mice and 5 TCR δ(-/-) mice were selected and enrolled into WT control group and TCR δ(-/-) group. Round full-thickness skin defect with diameter of 6 mm was made on the back of each mouse. The wound healing condition was observed immediately after injury and on post injury day (PID) 2, 4, 6, 8, 10, and the percentage of residual wound area was calculated. (3) Mice were selected to group and reproduce model of full-thickness skin defect as in experiment (2). On PID 3, the tissue of wound margin was collected for hematoxylin eosin staining, and the length of new epithelium was measured. (4) Mice were selected to group and reproduce model of full-thickness skin defect as in experiment (2). On PID 3, epidermal tissue of wound margin was collected to determine expression of proliferating cell nuclear antigen (PCNA) using Western blotting for evaluation of proliferation of epidermal cell. (5) Mice were selected to group and reproduce model of full-thickness skin defect as in experiment (2). On PID 3, epidermal tissue of wound margin was selected and digested into single-cell suspension, and apoptosis of cells was detected by flow cytometer. (6) Forty TCR δ(-/-) mice were selected to carry out the same treatment as in experiments (2)-(5). According to the random number table, these mice were enrolled into TCR δ(-/-) control group and TCR δ(-/-)+ DETC group, with 5 mice in each group for each experiment. Round full-thickness skin defect was made on the back of each mouse. DETC in the number of 1×10(5) (dissolution in 100 μL phosphate with buffer purity above 90%) were injected through multiple points of wound margin of mice in TCR δ(-/-)+ DETC group immediately after injury, and equal volume of phosphate buffer was injected into mice of TCR δ(-/-) control group with the same method as above. Data were processed with one-way analysis of variance for repeated measurement, t test, and Bonferroni correction. Results: (1) Along with the culture time elapse, the number of dendritic structures of DETC increased gradually. The percentage of T lymphocytes was 4.67% and 94.1% of these T lymphocytes were DETC. The purity of DETC on CD 15 was 18.50% and the purity of DETC on CD 30 was 98.70%. (2) Immediately after injury, the wound healing condition of mice in WT control group and TCR δ(-/-) group was similar. The wound healing speed of mice in TCR δ(-/-) group was slower than that in WT control group on PID 2-10. The percentages of residual wound area of mice in TCR δ(-/-) group on PID 2, 4, 6, 8, and 10 were increased significantly compared with those in WT control group (t=3.492, 4.425, 4.170, 4.780, 7.318, P<0.01). (3) The length of new epithelium of mice in TCR δ(-/-) group on PID 3 was (359 ± 15) μm, which was obviously shorter than that in WT control group [(462±26) μm, t=3.462, P<0.01]. (4) Immediately after injury, wound condition of mice in TCR δ(-/-)+ DETC group and TCR δ(-/-) control group was similar. Compared with TCR δ(-/-)+ DETC group, the wound healing speed of mice in TCR δ(-/-) control group were obviously slower on PID 2-10. The percentages of residual wound area of mice in TCR δ(-/-)+ DETC group on PID 2, 4, 6, 8, and 10 were decreased significantly compared with those in TCR δ(-/-) control group (t=2.308, 3.725, 2.698, 3.707, 6.093, P<0.05 or P<0.01). (5) On PID 3, the length of new epithelium of mice in TCR δ(-/-)+ DETC group was (465±31) μm, which was obviously longer than that in TCR δ(-/-) control group [(375±21) μm, t=2.390, P<0.05]. (6) On PID 3, PCNA expression of epidermal cell in wound margin of mice in TCR δ(-/-) group was 1.25±0.04, which was obviously lower than that in WT control group (2.01±0.09, t=7.415, P<0.01). (7) On PID 3, PCNA expression of epidermal cell in wound margin of mice in TCR δ(-/-)+ DETC group was 1.62±0.08, which was significantly higher than that in TCR δ(-/-) control group (1.05±0.14, t=3.561, P<0.05). (8) On PID 3, apoptosis rate of epidermal cell in wound margin of mice in TCR δ(-/-) group was (16.1±1.4)%, which was higher than that in WT control group [(8.1±0.6)%, t=5.363, P<0.01]. (9) On PID 3, apoptosis rate of epidermal cell in wound margin of mice in TCR δ(-/-)+ DETC group was (11.4±1.0)%, which was obviously lower than that in TCR δ(-/-) control group [(15.4±1.4)%, t=2.377, P<0.05]. Conclusions: DETC participates in the process of wound healing though promoting the proliferation of epidermal cells in wound margin and inhibit the apoptosis of these cells.

[Complete mitochondrial genomes of Paragonimus westermani in China and phylogenetic analysis of various geographical isolates]

OBJECTIVE

To compare the complete mitochondrial genome sequences of two phenotypes of Paragonimus westermani isolated from Fujian Province with different sizes of metacercariae, and perform a phylogenetic analysis of various geographical isolates of P. westermani from Asia, so as to identify the possible genetic characteristics associated with the P. westermani phenotypes.

METHODS

P. westermani metacercariae with different sizes (large metacercariae, 380-420 μm in diameter; small metacercariae, 320-340 μm) isolated from freshwater crabs were used to infect dogs, and the eggs and adult worms of P. westermani were collected from the dog stool samples and lung tissues. Then, the egg size and morphology were compared. In addition, genomic DNA was extracted from the adult worms of the two phenotypes of P. westermani and used for the PCR amplification to yield the complete mitochondrial genome sequence. Sequence structure and phylogenetic analyses were performed based on the complete mitochondrial genome of P. westermani.

RESULTS

Following infection with large and small P. westermani metacercariae, the adult worms recovered from the dog lung had a thick body, and had oral and ventral suckers. The ventral sucker was located slightly in front of the midline of the body, and testes, ovary and vitelline gland were seen in the adult worms. Following fixation, the adults appeared oval, with an approximately 1.7∶1 of the length-width ratio. The length and width of the eggs isolated from the fecal samples of dogs infected with large and small P. westermani metacercariae varied significantly, and the large metacercariae produced bigger eggs than the smaller metacercariae. Based on the morphological features of adults and eggs and the ITS2 sequences, both phenotypes were identified as P. westermani. The complete mitochondrial genome sequence analysis of adults showed almost consistent sequences in the protein-coding region of the mitochondrial genome of adult worms derived from large and small metacercariae, with a major variation seen in the former non-coding region. Sliding window analysis revealed the most polymorphic region within the ND4 gene across the mitochondrial genome from various geographical isolates of P. westermani, and phylogenetic analysis showed that both phenotypes were clustered into the Chinese branch of P. westermani, which was close to the Japanese branch and distinct from the South/Southeast Asian branch.

CONCLUSIONS

The genetic distance between the phenotypes of P. westermani isolated from Fujian Province is near at a mitochondrial genome level, with no remarkable genetic differentiation seen; however, the mutation and structural changes in the non-coding region may result in the phenotypic variations. In addition, there is a distinct variation of the evolutionary rate in the mitochondrial coding genes, suggesting the selection of appropriate molecular markers during the phylogenic researches.

Unique genetic profiles from cerebrospinal fluid cell-free DNA in leptomeningeal metastases of EGFR-mutant non-small-cell lung cancer: a new medium of liquid biopsy

Background

Leptomeningeal metastases (LM) are more frequent in non-small-cell lung cancer (NSCLC) with epidermal growth factor receptor (EGFR) mutations. Due to limited access to leptomeningeal lesions, the purpose of this study was to explore the potential role of cerebrospinal fluid (CSF) as a source of liquid biopsy in patients with LM.

Patients and methods

Primary tumor, CSF, and plasma in NSCLC with LM were tested by next-generation sequencing. In total, 45 patients with suspected LM underwent lumbar puncture, and those with EGFR mutations diagnosed with LM were enrolled.

Results

A total of 28 patients were enrolled in this cohort; CSF and plasma were available in 26 patients, respectively. Driver genes were detected in 100% (26/26), 84.6% (22/26), and 73.1% (19/26) of samples comprising CSF cell-free DNA (cfDNA), CSF precipitates, and plasma, respectively; 92.3% (24/26) of patients had much higher allele fractions in CSF cfDNA than the other two media. Unique genetic profiles were captured in CSF cfDNA compared with those in plasma and primary tissue. Multiple copy number variations (CNVs) were mainly identified in CSF cfDNA, and MET copy number gain identified in 47.8% (11/23) of patients was the most frequent one, while other CNVs included ERBB2, KRAS, ALK, and MYC. Moreover, loss of heterozygosity (LOH) of TP53 was identified in 73.1% (19/26) CSF cfDNA, which was much higher than that in plasma (2/26, 7.7%; P < 0.001). There was a trend towards a higher frequency of concomitant resistance mutations in patients with TP53 LOH than those without (70.6% versus 33.3%; P = 0.162). EGFR T790M was identified in CSF cfDNA of 30.4% (7/23) of patients who experienced TKI progression.

Conclusion

CSF cfDNA could reveal the unique genetic profiles of LM and should be considered as the most representative liquid biopsy medium for LM in EGFR-mutant NSCLC.

Effect of the imatinib treatment regimen on the postoperative prognosis of patients with high-risk gastrointestinal stromal tumors

Background: Surgical resection is the standard treatment for localized and potentially resectable gastrointestinal stromal tumors (GISTs), If the postoperative pathology diagnosis indicates that patients are at high risk of recurrence, they should be treated with imatinib. Even though the introduction of imatinib substantially improved the outcome of GIST patients, it is unclear whether different imatinib treatment regimens affect patients' survival. Methods: This retrospective study included 120 patients who underwent tumor resection for high-risk GISTs between January 2009 and October 2018. The patients were divided into three groups: one group of patients received postoperative imatinib adjuvant therapy regularly (regular treatment group); the second group was not treated with imatinib until they were found to have disease progression (observation group); the third group was treated with postoperative imatinib adjuvant therapy irregularly (irregularly treatment group). The progression-free survival (PFS) and overall survival (OS) were compared between the three groups, and the prognostic risk factors were analysed by the Cox regression model. Results: The median PFS was 45 months (range: 25-59). The 3- and 5-year PFS values were 71.3% and 49.9%, respectively. The PFS in the regular group was longer than in the observation group and irregular group (P<0.001). The median OS was 59 months (range:47-78). The 3- and 5-year OS values were 91.6% and 84.2%, respectively. There were no differences in OS among the three groups (P=0.150). The extent of radical resection (P<0.001) and intraoperative tumor rupture (P=0.005) were independent prognostic factors influencing OS. Conclusions: Irregular administration of imatinib was associated with a worse PFS, but it did not affect the OS of patients with high-risk GISTs. Avoiding intraoperative tumor rupture and R0 resection were associated with better survival.

[Characteristics of cervical lymph node metastasis of cN0 laryngeal carcinoma]

Objective: To investigate the incidence of occult cervical lymph node metastasis and the common neck level of metastases in cN0 laryngocarcinoma, and the relationship between the clinicopathologic features of laryngocarcinoma and cervical lymph node metastasis. Methods: A total of 506 cases with cN0 laryngocarcinoma treated at the First Affiliated Hospital of Chongqing Medical University between March 2011 and March 2018 were enrolled, and their medical records and follow-up data were retrospectively analyzed. Of them, 211 cases of were glottic carcinoma in stage T1 without neck dissection and they were observed by clinical follow-up; other 295 cases, including glottic carcinoma, supraglottic carcinoma and hypopharyngeal carcinoma in stage T2-T4 were treated with surgical resection of the primary lesions and selective neck dissection. SPSS 22.0 software was used to analyze the data. Results: The total incidence of cervical lymph node metastasis was 10.87%(55/506), with a lower incidence in T1 stage glottic carcinoma(6/211,2.84%) than that in other cases(49/295,16.61%). The incidence of cervical lymph node metastasis in glottic carcinoma (29/426, 6.81%) was lower than those in supraglottic carcinoma (22/71,30.99%) and subglottic carcinoma (4/9) (χ(2)=35.810,P<0.01).The pN+ rates of glottic carcinoma at T1, T2, T3 were 2.84%(6/211), 5.31%(6/113), 16.05%(13/81), and 19.05%(4/21), respectively (χ(2)=18.572, P<0.01). The pN+ rates of supraglottic carcinoma at T2, T3 and T4 were 3/13, 32.50%(13/40) and 6/13, respectively (χ(2)=3.649,P>0.05). The incidence of cervical lymph node metastasis in poorly differentiated carcinoma (17/42, 40.48%) was higher than those in moderately differentiated carcinoma (26/205, 12.68%) and high differentiated carcinoma(12/246, 4.88%)(χ(2)=36.356, P<0.01). Moreover, 85 pN+ lymph nodes were obtained by selective neck dissection, respectively 43(50.59%) in level Ⅱa, 30(35.29%) in level Ⅲ, 1(1.18%) in level Ⅳ and 11(12.94%) in level Ⅵ. Conclusions: The occult cervical lymph node metastasis was frequently found in cN0 laryngocarcinoma. Selective neck dissection should be performed with surgery for the primary lesions in T3-T4 glottic laryngeal cancer, T2-T4 supraglottic laryngeal cancer and subglottic carcinoma, and the neck dissection for level Ⅱa and Ⅲ is appropriate. It is required to detect pre-laryngeal and pre-tracheal lymph nodes in patients with subglottic laryngeal carcinoma.

[Effects of skin γδ T lymphocytes on wound healing of mice through regulating proliferation and differentiation of mice epidermal cells]

Objective: To explore effects of dendritic epidermal T cells (DETCs) and Vγ4 T lymphocytes on proliferation and differentiation of mice epidermal cells and the effects in wound healing of mice. Methods: (1) Six C57BL/6 male mice aged 8 weeks were collected and divided into control group and wound group according to random number table (the same grouping method below), with 3 mice in each group. A 4 cm long straight excision with full-thickness skin defect was cut on back of each mouse in wound group, while mice in control group received no treatment. On post injury day (PID) 3, mice in 2 groups were sacrificed, and skin within 5 mm from the wound margin on back of mice in wound group and normal skin on corresponding part of mice in control group were collected to make single cell suspensions. The percentage of Vγ4 T lymphocyte expressing interleukin-17A (IL-17A) and percentage of DETCs expressing insulin-like growth factor Ⅰ (IGF-Ⅰ) were detected by flow cytometer. (2) Ten C57BL/6 male mice aged 8 weeks were collected and divided into control group and Vγ4 T lymphocyte depletion group with 5 mice in each group. Mice in Vγ4 T lymphocyte depletion group were injected with 200 g Vγ4 T lymphocyte monoclonal neutralizing antibody of Armenian hamster anti-mouse intraperitoneally, and mice in control group were injected with the same amount of Armenian hamster Ig intraperitoneally. One hole with full-thickness skin defect was made on each side of spine of back of each mice. The wound healing was observed on PID 1-8, and percentage of remaining wound area was calculated. (3) Six C57BL/6 male mice aged 8 weeks were grouped and treated in the same way as in experiment (2), with 3 mice in each group. On PID 3, expressions of IL-17A and IGF-Ⅰ in epidermis on margin of wound were detected with Western blotting. (4) Thirty C57BL/6 male mice aged 3 days were sacrificed, and epidermal cells were extracted. The keratin 14 positive cell rate was examined by flow cytometer (the same detecting method below). (5) Another batch of mouse epidermal cells were collected and divided into control group, IGF-Ⅰ group, and IL-17A group, with 3 wells in each group (the same well number below). Cells in IGF-Ⅰ group and IL-17A group were added with 1 mL recombinant mouse IGF-Ⅰ and IL-17A with final mass concentration of 100 ng/mL respectively, while cells in control group were added with the same amount of sterile phosphate buffered saline (PBS). On post culture day (PCD) 5, keratin 14 negative cell rate was examined. Another batch of mouse epidermal cells were collected, grouped, and treated in the same way as aforementioned experiment, and keratin 10 positive cell rate was examined on PCD 10. (6) Another batch of mouse epidermal cells were collected and added with 4 mmol/L 5(6)-carboxyfluorescein diacetate N-succinimidyl ester (CFSE) solution, and divided into control 0 d group, control 7 d group, IGF-Ⅰ group, and IL-17A group. Cells in IGF-Ⅰ group and IL-17A group were treated in the same way as the corresponding groups in experiment (5), and cells in control 0 d group and control 7 d group were treated in the same way as the control group in experiment (5). The CFSE fluorescence peaks were examined on PCD 0 of control 0 d group and PCD 7 of the other 3 groups. (7) Another batch of mouse epidermal cells were collected and divided into control group and IGF-Ⅰ group. Cells in IGF-Ⅰ group were added with 1 mL recombinant mouse IGF-Ⅰ with final mass concentration of 100 ng/mL, and cells in control group were added with the same amount of sterile PBS. On PCD 5, cells were underwent keratin 14 staining and CFSE staining as aforementioned, and keratin 14 negative cell rate of CFSE positive cells was examined. Another batch of mouse epidermal cells were collected and divided into control group and IL-17A group. Cells in IL-17A group were added with 1 mL recombinant mouse IL-17A with final mass concentration of 100 ng/mL, and cells in control group were added with the same amount of sterile PBS. On PCD 5, keratin 14 negative cell rate of CFSE positive cells was examined. Data were processed with one-way analysis of variance and t test. Results: (1) On PID 3, percentage of DETC expressing IGF-Ⅰ in normal epidermis of control group was (9.9±0.8)%, significantly lower than (19.0±0.6)% of epidermis around margin of wound group (t=8.70, P<0.01); percentage of Vγ4 T lymphocyte expressing IL-17A in normal epidermis of control group was (0.123±0.024)%, significantly lower than (8.967±0.406)% of epidermis around margin of wound group (t=21.77, P<0.01). (2) On PID 1-4, there was obvious inflammatory reaction around wounds of mice in control group, and on PID 5-8, the wound area was still large. On PID 1-4, there was slight inflammatory reaction around wounds of mice in Vγ4 T lymphocyte depletion group, and on PID 5-8, the wound area was significantly reduced. On PID 3-7, percentages of residual wound area in Vγ4 T lymphocyte depletion group were significantly lower than those in control group (t=5.92, 5.74, 7.17, 5.38, 5.57, P<0.01), while percentages of residual wound area in two groups on PID 1, 2, 6 were similar (t=1.46, 3.17, 3.10, P>0.05). (3) On PID 3, compared with those in control group, expression of IL-17A and IGF-Ⅰ in epidermis around wound margin of mice in Vγ4 T lymphocyte depletion group was markedly decreased and increased respectively (t=8.47, 19.24, P<0.01). (4) The keratin 14 positive cell rate of mouse epidermal cells was 94.7%. (5) On PCD 5, the keratin 14 negative cell rate of mice in control group was markedly higher than that of IGF-Ⅰ group, while significantly lower than that of IL-17A group (t=7.25, 5.64, P<0.01). On PCD 10, the keratin 10 positive cell rate of mice in control group was significantly higher than that of IGF-Ⅰ group, while significantly lower than that of IL-17A group (t=3.99, 10.82, P<0.05 or P<0.01). (6) Compared with that of control 0 d group, CFSE fluorescence peaks of mouse epidermal cells in control 7 d group, IGF-Ⅰ group, and IL-17A group on PCD 7 shifted to the left. Compared with that of control 7 d group, CFSE fluorescence peaks of mouse epidermal cells in IGF-Ⅰ group and IL-17A group on PCD 7 shifted to the left. (7) On PCD 5, keratin 14 negative cell rate of CFSE positive cells of mice in control group was significantly higher than that in IGF-Ⅰ group (t=9.91, P<0.01), and keratin 14 negative cell rate of CFSE positive cells of mice in control group was markedly lower than that in IL-17A group (t=6.49, P<0.01). Conclusions: In the process of wound healing, IGF-Ⅰ secreted by DETC can promote the proliferation of mouse keratin 14 positive epidermal cells and inhibit their terminal differentiation, while IL-17A secreted by Vγ4 T lymphocyte can promote the proliferation and terminal differentiation of mouse keratin 14 positive epidermal cells, thus both IGF-Ⅰ and IL-17A can affect wound healing.

[Establishment and optimization of hepatocyte steatosis model]

Objective: To establish a new model of hepatic steatosis cells by optimizing the original ethanol or high fat, the present study proposed an in vitro hepatocyte steatosis model for the study of fatty liver. Methods: Oil red O staining was used to observe the effects of fetal bovine serum, oleic acid and ethanol on lipid accumulation in human liver cell line L02 in a concentration- and time-dependent manner. RT-PCR was used to detect the mRNA expression levels of PPAR-γ and AP-2, and the suitable conditions for the establishment of hepatocyte steatosis model were screened out. A t-test was used for comparison between the two groups, and one-way Analysis of Variance (ANOVA) was used in more than three groups. Results: Oil red O staining showed the number of reddish-orange lipid droplets in L02 cells gradually increased with the increase of fetal bovine serum, oleic acid and ethanol in a concentration - and time-dependent manner. Compared with 0.00% oleic acid and 2% ethanol, the count value of red particle was 100.00% ± 17.63% at the beginning and after 24 h, 0.003% oleic acid and 2% ethanol jointly acted in L02 cells. After incubation for 48 hours with 2% ethanol and serum-free DMEM medium, the accumulation of lipid droplets was the highest with a count value of 802.38%+71.06%(t = 42.36, P < 0.001). RT-PCR analysis showed the lipid accumulation induced by this method was positively correlated with the mRNA expression of PPAR-γ and AP-2. Conclusion: L02 cells were successfully exposed to high fat and ethanol, and the hepatocyte steatosis model was established and optimized, suggesting that the occurrence of hepatic cell steatosis was related to the up-regulation of PPAR-γ and AP-2.

Oxygen plasma-fragmented KMnF3 nanoparticle benefits contrast enhancement for MRI of a patient-derived tumor xenograft model

Magnetic nanoparticles (NPs) are emerging as promising candidates for the next generation of image contrast agents and their performance is largely dependent on physicochemical properties. In this paper, a new type of 'top-down' fabrication technique was developed to synthesize ultrasmall magnetic NPs as a contrast enhancer. In a detailed, home-made oxygen plasma generator, fragments of larger KMnF₃ NPs (22 nm) were broken down into smaller (<5 nm) particles with enhanced hydrophilicity. As massive activated oxygen species were produced during the process, the plasma was able to severely etch the NPs, and vacuum UV light irradiated them heavily as well, leaving them with weak crystallinity, splitting them into ultrafine particles. Also their surface transformed from hydrophobic to hydrophilic by oxidizing the passivated ligand, evidenced by the spectroscopy and microscopy results. The fragmented NPs are characteristic of unprecedented high longitudinal relaxivity (r₁ = 35.52 mM^-1.s^-1) and appropriate biocompatibility. In a healthy mouse, the ultrafine NPs did not exert observable toxicity, this was evaluated by histology of the main organs and hemogram analysis, including kidney and liver function analysis. More interestingly, the ultrasmall NPs had a very long circulation time, as its blood half-life was around 20 h. When applied as a contrast enhancer for MRI of the patient-derived tumor xenograft model, the accumulation of KMnF₃ NPs within the tumor had an average of 12.13% ID per gram, which greatly shortened the relaxation time of the tumor. Therefore the control-to-noise ratio was significantly enhanced, relative to the same dosage of Gadopentetetic acid (Magvenist) (P < 0.001). Our primary results demonstrate that fragmentation of the NPs via our home-made oxygen plasma technique might be an effective route for fabricating ultrasmall NPs, and benefit their contrast effect when applied as MRI enhancers for clinical diagnosis of tumors.

Bone morphogenetic proteins for articular cartilage regeneration

Degeneration of articular cartilage (AC) tissue is the most common cause of osteoarthritis (OA) and rheumatoid arthritis. Bone morphogenetic proteins (BMPs) play important roles in bone and cartilage formation. This article reviews the experimental and clinical applications of BMPs in cartilage regeneration. Experimental evidence indicates that BMPs play an important role in protection against cartilage damage caused by inflammation or trauma, by binding to different receptor combinations and, consequently, activating different intracellular signaling pathways. Loss of function of BMP-related receptors contributes to the decreased intrinsic repair capacity of damaged cartilage and, thus, the multifunctional effects of BMPs make them attractive tools for the treatment of cartilage damage in patients with degenerative diseases. However, the development of BMP therapy as a treatment modality for cartilage regeneration has been hampered by certain factors, such as the eligibility of participants in clinical trials, financial support, drug delivery carrier safety, availabilities of effective scaffolds, appropriate selection of optimal dose and timing of administration, and side effects. Further research is needed to overcome these issues for future routine clinical applications. Research and development leading to the successful application of BMPs can initiate a new era in the treatment of cartilage degenerative diseases like OA.

[Efficacy and safety of transbronchial cryobiopsy in the etiologic diagnosis of diffuse lung disease]

Objective: To assess the efficacy and safety of transbronchial cryobiopsy (TBCB) for the etiologic evaluation of diffuse lung disease (DLD). Methods: Between December 2015 to April 2017, a total of 38 patients with DLD met the inclusion criteria for TBCB in the First Affiliated Hospital of Chongqing Medical University, and 35 of them consented to undergo the procedure under rigid or flexible bronchoscopy. On the tissues obtained from the 35 patients, histopathologic and microbiological evaluations were performed, and together with clinical and radiological manifestations, diagnoses were made and the efficacy of TBCB in the diagnosis of DLD was confirmed, and then therapies were planned accordingly. Complications of the biopsy procedures were recorded. Results: Of the 35 patients who were enrolled, 24 underwent TBCB under rigid bronchoscopy and 11 under flexible bronchoscopy. Another 3 patients refused the procedure due to disinclination to invasive examinations. One single procedure of TBCB took (51.8±19.2) min on average, the median number of tissues obtained was 6 (5, 8), and the median area of tissues was 15 (9, 20) mm(2).Definite diagnoses were reached in 33 patients, including idiopathic nonspecific interstitial pneumonia (n=8), connective tissue disease-interstitial lung disease (n=8), occupational lung disease (n=4), idiopathic pulmonary fibrosis (n=3), interstitial pneumonia with autoimmune features (n=3), tuberculosis (n=2), cryptogenic organization pneumonia (n=1), acute interstitial pneumonia (n=1), pulmonary infection (n=1), hypersensitivity pneumonia (n=1) and sarcoidosis (n=1). Diagnostic yield was 94.3% (33 out of 35 cases diagnosed). Pneumothorax occurred in 3 patients (1 patients with mild pneumothorax , 1 moderate and 1 severe), and were resolved with thoracic puncture or pleural drainage. Bleeding occurred in all 24 patients who received TBCB under rigid bronchoscopy (11 patients with mild bleeding, 12 moderate and 1 severe) and was controlled after coagulation measures. After one month of treatment according to the diagnoses acquired with cryobiopsy, the condition was cured in 1 patient (3.0%), alleviated in 17 (51.5%), stable in 11 (33.3%), and deteriorated in 4 (12.1%). Conclusion: TBCB yields reliable diagnoses with a good safety profile.

[The effects of microRNA-7 on proliferation and invasion of hepatocellular carcinoma HepG2 cells]

Objective: To investigate the effects of overexpression of microRNA-7 (miR-7) on the proliferation and invasion of HepG2 cells and the underlying mechanism in vitro. Methods: The relative expression levels of miR-7 and Raf1 in hepatocellular carcinoma (HCC) tissues and adjacent normal tissues (ANT) were detected by quantitative real time-PCR (qRT-PCR). The relationship between the expression of miR-7 and the characteristics of HCC patients was analyzed. Cells were divided into blank control group, negative control (NC) group and miR-7 mimics transfected group, miR-7 mimics and NC were transfected into HepG2 cells by Lipofectamine™2000. The relative expression of miR-7 was detected by qRT-PCR. The proliferation ability of HepG2 cells was detected by 3-(4, 5-dimethyl-2-thiazolyl)-2, 5-diphenyl-2-H-tetrazolium bromide (MTT) assay. The invasion of HepG2 cells was detected by Transwell assay. The target genes of miR-7 were predicted by TargetScan and the binding effect of miR-7 on the 3'UTR of Raf1 was verified by dual luciferase reporter assay.The expressions of Raf1 protein in hepatocellular carcinoma tissues, normal tissues and miR-7 mimics transfected HepG2 cells was detected by Western blot. The correlation of the levels of miR-7 and Raf1 mRNA was determined by Pearson correlation analysis. Results: The relative expression level of miR-7 in HCC was 0.49±0.02, significantly lower than in ANT (1.21±0.05, P<0.01). The level of miR-7 was significantly correlated the tumor volume, metastasis and prognosis of HCC patients (P<0.05). The relative expression level of miR-7 in miR-7 mimics transfected HepG2 group was 12.67±0.40, significantly higher than that in blank group (P<0.01). Compared with the blank group, the A value and invasion ability of miR-7 mimics transfected group were significantly down-regulated at 48 hours and 72 hours after transfection (P<0.01). Compared with miR-7 NC group, the luciferase activity of wild-type Raf1 reporter gene in miR-7 mimics transfected group was significantly reduced (P<0.01). The relative expression of Raf1 protein in HCC was 3.15±0.10, significant higher than in ANT (0.53±0.03, P<0.01). The relative expression of Raf1 protein in miR-7 mimics transfected group was 0.24±0.01, significantly lower than in miR-7 NC group (0.98±0.02, P<0.01). Furthermore, an negative correlation was observed between the levels of miR-7 and Raf1 in HCC tissues (P<0.05). Conclusions: The expression of miR-7 in HCC is significantly decreased and inversely correlated with poor survival of HCC patients. Overexpression of miR-7 can inhibit the proliferation and invasion ability of hepatocellular carcinoma cells HepG2 by downregulating Raf1 in vitro.

Effects of dietary supplementation of formaldehyde and crystalline amino acids on gut microbial composition of nursery pigs

Formaldehyde-based feed additives are approved in the US for Salmonella control and reducing bacterial contamination in animal feed. However, we hypothesize formaldehyde inclusion in swine diets may influence gut microbial composition due to its antimicrobial properties which might negatively influence microbial populations and pig growth performance. Also, formaldehyde inclusion in diets is known to reduce the dietary availability of amino acids. Therefore, our study was conducted to characterize if the effects of feed formaldehyde-treatment are due to influences on microbial population or diet amino acid (AA) sources. Dietary treatments were arranged in a (2 × 2) + 1 factorial with formaldehyde treatment (none vs. 1000 ppm formaldehyde) and crystalline AA inclusion (low vs. high) with deficient AA content plus a positive control diet to contain adequate AA content without dietary formaldehyde. Treating diets with formaldehyde reduced growth rate (P = 0.001) while the AA inclusion had no evidence of impact. Formaldehyde reduced feed bacterial content and altered fecal microbial communities (P < 0.05). Therefore, we conclude that the negative influence on growth was due to the impact on the fecal microbial community. Implications are that strategies for feed pathogen control need to take into account potential negative impacts on the gut microbial community.

Fisetin suppresses malignant proliferation in human oral squamous cell carcinoma through inhibition of Met/Src signaling pathways

Fisetin (3,7,3',4'-tetrahydroxyflavone) is a dietary flavonoid and has been indicated as a novel anti-cancer agent in several types of cancer cells. However, the mechanisms underlying the effect of fisetin in human oral squamous cell carcinoma (OSCC) remain unclear. Here, we report that fisetin significantly inhibits tumor cell proliferation and induces apoptosis in OSCC (UM-SCC-23 and Tca-8113) cancer cell lines. Further analysis demonstrates that fisetin also inhibits Met/Src signaling pathways using the PathScan^® receptor tyrosine kinases (RTK) Signaling Antibody Array Kit. Fisetin resulted in decreased basal expression of Met and Src protein in UM-SCC-23 cancer cell lines, which validated by western blot. A student's t-test (two-tailed) was used to compare differences between groups. Furthermore, fisetin significantly inhibited the expression of a disintegrin and metalloproteinase 9 (ADAM9) protein in OSCC cells. Taken together, these results provide novel insights into the mechanism of fisetin and suggest potential therapeutic strategies for human OSCC by blocking the Met/Src signaling pathways.

[Progress in Application of Measuring Skeleton by CT in Forensic Anthropology Research]

Individual identification by measuring the human skeleton is an important research in the field of forensic anthropology. Computed tomography （CT） technology can provide high-resolution image of skeleton. Skeleton image can be reformed by software in the post-processing workstation. Different skeleton measurement indexes of anthropology, such as diameter, angle, area and volume, can be measured on section and reformative images. Measurement process is barely affected by human factors. This paper reviews the literatures at home and abroad about the application of measuring skeleton by CT in forensic anthropology research for individual identification in four aspects, including sex determination, height infer, facial soft tissue thickness measurement and age estimation. The major technology and the application of CT in forensic anthropology research are compared and discussed, respectively.

Initial empiric antibiotic therapy for community-acquired pneumonia in Chinese hospitals

OBJECTIVES

Studies on treatment of community-acquired pneumonia (CAP) in China are scarce. We performed a study to investigate empiric antibiotic practices for patients hospitalized with CAP in China and the risk factors for treatment failure.

METHODS

Data were collected from a national Chinese hospitalization database. Adult patients who were diagnosed with CAP between 1 October 2014 and 30 September 2015 were identified. We studied initial empiric antibiotic regimens, microbiologic sampling, treatment failure, in-hospital mortality and length of hospital stay.

RESULTS

We included 18 043 adult patients from 185 hospitals who met all the study inclusion criteria. The most common initial antibiotic regimen for CAP was monotherapy with a fluoroquinolone (14.8%, 2671/18 043). The most common initial antibiotic (used alone or in combination with other antibiotics) was levofloxacin (15.7%, 4597/29 278 (this denominator represents the total number of initial antibiotics)). The microbiologic sampling rate was 26.9% (4851/18 043). A total of 4050 (22.4%) of 18 043 patients experienced treatment failure. Multivariate logistic regression demonstrated that older age, male sex, coexisting lung cancer and use of regimens not covering atypical pathogens were risk factors for treatment failure. In-hospital mortality was 2.1% (380/18 043). The median hospital length of stay was 11 days (interquartile range, 8-15 days).

CONCLUSIONS

Patients receiving Chinese guideline-adherent regimens had better outcomes, and atypical pathogen active regimens were associated with a lower treatment failure rate and shorter length of hospital stay.

KLF2 inhibits cell growth via regulating HIF-1α/Notch-1 signal pathway in human colorectal cancer HCT116 cells

The transcription factor Krüppel-like factor 2 (KLF2) has been shown to function as a tumor suppressor and regulate biological processes of cancer cells, such as cell growth, cell apoptosis and angiogenesis. However, the function and mechanism of KLF2 in colorectal cancer (CRC) is still unknown. In the present study, we show that the expression of KLF2 is diminished in a cohort of CRC cell lines. Also, KLF2 overexpression remarkably inhibits HCT116 and SW480 cell survival and proliferation. Moreover, cell death detection ELISA plus assay showed that KLF2 overexpression increased HCT116 cell proliferation. Caspase-3/7 activity also increased in HCT116 cells transfected with PcDNA3.1-KLF2. Further studies showed that KLF2 significantly suppresses the expression of Notch-1 and is dependent on the decline of the HIF-1α level. Most importantly, silencing Notch-1 expression or HIF-1α level both impair the action of KLF2 overexpression in CRC cells. Collectively, we demonstrated that KLF2 mediates CRC cell biological processes including cell growth and apoptosis via regulating the HIF-1α/Notch-1 signal pathway. These results indicated that KLF2 plays an important role in CRC and provided novel insight on the function of KLF2 in tumor progression.

Hydrodynamic analysis of human swimming based on VOF method

A 3-D numerical model, based on the Navier-Strokes equations and the RNG k-ε turbulence closure, for studying hydrodynamic drag on a swimmer with wave-making resistance taken into account is established. The volume of fluid method is employed to capture the undulation of the free surface. The simulation strategy is evaluated by comparison of the computed results with experimental data. The computed results are in good agreement with data from mannequin towing experiments. The effects of the swimmer's head position and gliding depth on the drag force at different velocities are then investigated. It is found that keeping the head aligned with the body is the optimal posture in streamlined gliding. Also wave-making resistance is significant within 0.3 m depth from the free surface.

Absence of Magnetic Thermal Conductivity in the Quantum Spin-Liquid Candidate YbMgGaO_{4}

We present the ultralow-temperature specific heat and thermal conductivity measurements on single crystals of YbMgGaO_{4}, which was recently argued to be a promising candidate for a quantum spin liquid (QSL). In a zero magnetic field, a large magnetic contribution of specific heat is observed, and exhibits a power-law temperature dependence (C_{m}∼T^{0.74}). On the contrary, we do not observe any significant contribution of thermal conductivity from magnetic excitations. In magnetic fields H≥6  T, the exponential T dependence of C_{m} and the enhanced thermal conductivity indicate a magnon gap of the fully polarized state. The absence of magnetic thermal conductivity at the zero field in this QSL candidate puts a strong constraint on the theories of its ground state.

Interleukin-2 reverses CD8(+) T cell exhaustion in clinical malignant pleural effusion of lung cancer

Malignant pleural effusion (MPE) is a poor prognostic sign for cancer patients, whereas the functional condition of MPE CD8(+) T cells is unknown. Intracavitary immunotherapy with interleukin (IL)-2 has been proven effective in controlling MPE. To elucidate the underlying mechanism, 35 lung cancer (LC) patients with MPE and 12 healthy donors were included in this study. For the IL-2 therapy experiments, after draining partial MPE, we treated 14 patients by administrating IL-2 (3 or 5 × 10(6) U in 50 ml saline) into the thoracic cavity. Before and after IL-2 treatment (40-48 h), the MPE and peripheral blood (PB) were obtained from the subjects. PB from healthy volunteers was collected as control. The expression of programmed cell death 1 (PD-1), granzyme B (GzmB), interferon (IFN)-γ and the proliferation were analysed in CD8(+) T cells from MPE and PB. The CD8(+) T cells in the MPE of LC patients showed lowest GzmB, IFN-γ and proliferation but highest PD-1 expression, compared with that in PB of LC patients and healthy donors. IL-2 treatment reduced the expression of PD-1, increased the expression of GzmB and IFN-γ and enhanced the proliferation of CD8(+) T cells in MPE. In addition, IL-2 treatment reduced carcino-embryonic antigen (CEA) level in MPE. These results indicate that MPE CD8(+) T cells exhibit exhaustion phenotype which can be reversed by IL-2 therapy.