Community diversity and abundance of ammonia-oxidizing archaea and bacteria in shrimp pond sediment at different culture stages

AIMS

Ammonia oxidation is a significant process of nitrogen cycles in a lot of ecosystems sediments while there are few studies in shrimp culture pond (SCP) sediments. This paper attempted to explore the community diversity and abundance of ammonia-oxidizing archaea (AOA) and ammonia-oxidizing bacteria (AOB) in SCP sediments at different culture stages.

METHODS AND RESULTS

We collected SCP sediments and analysed the community diversity and abundance of AOA and bacteria in shrimp pond sediment at different culture stages using the ammonia monooxygenase (amoA) gene with quantitative PCR (qPCR) and 16S rRNA gene sequencing. The AOB-amoA gene abundance was showed higher than AOA-amoA gene abundance in SCP sediments on Day 50 and Day 60 after shrimp larvae introducing into the pond, and the diversity of AOA in SCP sediments was higher than that of AOB. The phylogenetic tree revealed that the most of AOA were the member of Nitrosopumilus and Nitrososphaera, and the majority of AOB sequences were clustered into Nitrosospira, Nitrosomonas clusters 6a and 7. The AOA community has close relationship with total organic carbon (TOC), pH, total phosphorus (TP), nitrate reductase, urease, acid phosphatase and β-glucosidase. The AOB community was related to TOC, C/N and nitrate reductase.

CONCLUSIONS

AOA and AOB play the different ecological roles in SCP sediments at different culture stages.

SIGNIFICANCE AND IMPACT OF THE STUDY

Our results suggested that the different community diversity and abundance of AOA and AOB in SCP sediments, which may improve our ecological cognition of shrimp culture stages in SCP ecosystems.

[Efficacy and safety of generic azacitidine in Chinese patients with higher-risk myelodysplastic syndromes: a multicenter, prospective, single-arm study]

Objective: To evaluate the efficacy, safety, and pharmacokinetics of the generic azacitidine in Chinese patients with higher-risk myelodysplastic syndromes(MDS). Methods: Between October 2013 and 2016, 72 patients were eligible for enrollment at 9 sites from China received generic subcutaneous azacitidine 75 mg·m(-2)·d(-1) for 7 days per 28-day cycle, for ≥6 cycles. Pharmacokinetic blood samples were collected on day 1 of a single-dose. Results: For each patient at cycle 6 or at the time of study discontinuation, whichever came first, the overall response rate, which included complete remission (CR)and partial remission(PR), was 6.9%(5/72), the rate of patients who had the best effect with CR or PR during the treatment was 12.5%(9/72). Patients who were dependent on red-blood-cell transfusions and platelet transfusions at baseline became transfusion independent were 46.3%(19/41)and 41.2% (7/17), respectively. The median time of treatment was 6 cycles, and the median OS was 16.1 months (95%CI 10.9-20.6 months). For 36 patients(50%)received treatment at ≥6 cycles, and the median OS was 22.3 months(95%CI 16.1- not evaluative). Most common grade Ⅲ-Ⅳ hematologic treatment-emergent adverse events were neutropenia(55%), leukopenia(47%), and thrombocytopenia(61%). Pharmacokinetic profiles were similar for generic and original azacitidine in Chinese patients. Conclusion: Generic azacitidine treatment was favorable and safe and can be used as a standard treatment for patients with higher-risk MDS.

Let-7 participates in the regulation of inflammatory response in spinal cord injury through PI3K/Akt signaling pathway

OBJECTIVE

To study the potential mechanism of let-7 in participating in the regulation of inflammatory response in spinal cord injury (SCI).

MATERIALS AND METHODS

A total of 40 male Sprague-Dawley rats were randomly divided into four groups: group A (Sham, n=10), group B (SCI+NC, n=10), group C (SCI+antagomir, n=10), and group D (SCI+mimics, n=10). The SCI model was established via operation in all groups. After successful modeling, let-7-antagomir negative control (80 mg/kg) was intraperitoneally injected in SCI+NC group at 5 d, an equal amount of let-7-antagomir was intraperitoneally injected in SCI+antagomir group at 5 d, and an equal amount of let-7-mimics was intraperitoneally injected in SCI+mimics group at 5 d. The inflammatory cells in experimental groups and control group were observed via hematoxylin-eosin (HE) staining. At the same time, the expression of let-7 in the four groups was detected via Reverse Transcription-Polymerase Chain Reaction (RT-PCR), the expressions of phosphatidylinositol 3-hydroxy kinase (PI3K) and protein kinase B (Akt) in all groups were detected via Western blotting, and the inflammatory index levels in each group were detected via enzyme-linked immunosorbent assay (ELISA).

RESULTS

In Sham group, it was observed via HE staining that there were only a few bleeding or inflammatory cells. In SCI+NC group, bleeding and inflammatory cells basically tended to be stable. There were a large number of inflammatory cells in SCI+mimics group, while there were some inflammatory cells in SCI+antagomir group, but showing a decreasing trend compared with SCI+NC group. It was found in the RT-PCR detection of let-7 expression level in all groups that the expression of let-7 significantly declined in SCI+antangomir group compared with that in Sham group and SCI+NC group, and there were significant differences (p<0.01). The expression of let-7 was significantly increased in SCI+mimics group compared with that in Sham group and SCI+NC group, and there were significant differences (p<0.01). The results of Western blotting revealed that the PI3K and Akt protein expressions were significantly decreased in SCI+mimics group compared with those in SCI+antagomir group, SCI+NC group, and Sham group (p<0.05). The ELISA results showed that the levels of inflammatory factors in SCI+mimics group, SCI+antagomir group, and SCI+NC group were significantly higher than those in Sham group. In SCI+mimics group, the levels of inflammatory factors were abnormally high and reached extremely significant levels (p<0.05), indicating that let-7 promotes the inflammatory response after SCI.

CONCLUSIONS

Let-7 participates in the regulation of inflammatory response in SCI through the PI3K/Akt signaling pathway.

LINC00968 accelerates the progression of epithelial ovarian cancer via mediating the cell cycle progression

OBJECTIVE

The aim of this study was to clarify the potential role of LINC00968 in the progression of epithelial ovarian cancer (EOC) and the underlying mechanism.

PATIENTS AND METHODS

The relative expression level of LINC00968 in EOC tissues (n=40) and normal ovarian tissues (n=40) was determined by quantitative Real Time-Polymerase Chain Reaction (qRT-PCR). LINC00968 expression in human-derived ovarian cancer cell lines was examined by qRT-PCR as well. After transfection of LINC00968 small-interfering RNA (siRNA) in ovarian cancer cells, cell cycle progression and cell proliferation were evaluated through flow cytometry, Cell Counting Kit-8 (CCK-8) and colony formation assay, respectively. Tumor xenograft was conducted in nude mice to elucidate the function of LINC00968 in EOC tumorigenesis in vivo. Furthermore, the relative expression levels of cell cycle factors and protein kinase B/extracellular-signal-regulated kinase (AKT/ERK) in ovarian cancer cells influenced by LINC00968 were detected by Western blot.

RESULTS

LINC00968 was significantly up-regulated in EOC tissues when compared with normal control tissues. Meanwhile, LINC00968 expression was positively correlated with the prognosis of EOC. Transfection of LINC00968 siRNA in HEY and HO8910 cells markedly attenuated proliferative ability and arrested cell cycle in the G1 phase. Knockdown of LINC00968 remarkably suppressed tumor growth of EOC in nude mice. The silence of LINC00968 significantly downregulated Cyclin D, Cyclin E and CDK4, whereas upregulated p16 and p21. In addition, AKT and ERK pathways were inhibited by knockdown of LINC00968 in ovarian cancer cells.

CONCLUSIONS

LINC00968 expression is markedly upregulated in EOC. Meanwhile, it arrests the cell cycle in the G1 phase by inhibiting the ERK and AKT pathways, thus accelerating EOC progression.

[Blood pressure control and influencing factors in hypertension patients with metabolic syndrome]

Objective: To investigate the blood pressure control and its influencing factors in hypertension patients with MS. Methods: Between January 2017 and December 2018, more than 78 000 residents aged 35-75 years selected through convenient sampling were invited to participant in China Patient-Centered Evaluative Assessment of Cardiac Event Million Persons Project in Fujian province, physical and laboratory tests were conducted for them, and their basic information were recorded. A total of 5 281 hypertension patients with MS were included in the study. Results: The treatment rate of hypertension patients with MS was 55.5%, and the control rate was 7.2%. The control rate was higher in patients who were older, women, had advanced education level, had history or family history of cardiovascular disease. The results of multivariate analysis indicated that living area (urban or rural), cardiovascular history, diabetes, urine protein, BMI had impacts on both treatment and control of hypertension. Family history of cardiovascular disease, age, self-management of hypertension, dyslipidemia, waist circumference and drinking had impacts on the treatments, and gender had effects on the control. Conclusions: The treatment rate of hypertension patients with MS was unsatisfactory and the control rate was low. Intervention should be strengthened in rural area, males and young age groups, and activity of self-management group of hypertension should be conducted regularly.

[Interpretation for the group standards in guidelines for personal protection against coronavirus disease 2019 for diseases control person]

As an emerging infectious disease, the COVID-19 threatened the safety of personnel in the prevention and control during the COVID-19 pandemic. Beijing Association of Preventive Medicine organizes the Beijing CDC and other organizations drafted the group standard entitled "Guidelines for personal protection against coronavirus disease 2019 for diseases control person (T/BPMA 0002-2020)" , according to years of scientific research on personal protection. Based on the principles of emphasizing the scientific, normative and safe nature, the standard was drafted to put forward the reasonable selection and correct use of personal protective equipment for disease control personnel, as well as the procedures for personal protective equipment. The standard provided a standardized basis for ensuring the safety of disease control personnel in contacting and handling of the new coronary pneumonia outbreaks with high risks.

Stillbirths in China: a nationwide survey

Objective

To estimate a stillbirth rate at 24 or more gestational weeks in 2015–2016 and to explore potentially preventable causes in China.

Design

A multi‐centre cross‐sectional study.

Setting

Ninety‐six hospitals distributed in 24 (of 34) provinces in China.

Population

A total of 75 132 births at 24 completed weeks of gestation or more.

Methods

COX Proportional Hazard Models were performed to examine risk factors for antepartum and intrapartum stillbirths. Population attributable risk percentage was calculated for major risk factors. Correspondence analysis was used to explore region‐specific risk factors for stillbirths.

Main outcome measures

Stillbirth rate and risk factors for stillbirth.

Results

A total of 75 132 births including 949 stillbirths were used for the final analysis, giving a weighted stillbirth rate of 13.2 per 1000 births (95% CI 7.9–18.5). Small for gestational age (SGA) and pre‐eclampsia/eclampsia increased antepartum stillbirths by 26.2% and 11.7%, respectively. Fetal anomalies increased antepartum and intrapartum stillbirths by 17.9% and 7.4%, respectively. Overall, 31.4% of all stillbirths were potentially preventable. Advanced maternal age, pre‐pregnant obesity, chronic hypertension and diabetes mellitus were important risk factors in East China; low education and SGA were major risk factors in Northwest, Southwest, Northeast and South China; and pre‐eclampsia/eclampsia and intrapartum complications were significant risk factors in Central China.

Conclusions

The prevalence of stillbirth was 13.2 per 1000 births in China in 2015–2016. Nearly one‐third of all stillbirths may be preventable. Strategies based on regional characteristics should be considered to reduce further the burden of stillbirths in China.

Tweetable abstract

The stillbirth rate was 13.2 per 1000 births in China in 2015–2016 and nearly one‐third of all stillbirths may be preventable.

The stillbirth rate was 13.2 per 1000 births in China in 2015–2016 and nearly one‐third of all stillbirths may be preventable.

Older age of childhood type 1 diabetes onset is associated with islet autoantibody positivity >30 years later: the Pittsburgh Epidemiology of Diabetes Complications Study

AIMS

To examine the association between islet autoantibody positivity and clinical characteristics, residual β-cell function (C-peptide) and prevalence of complications in a childhood-onset (age <17 years), long-duration (≥32 years) type 1 diabetes cohort.

METHODS

Islet autoantibodies (glutamic acid decarboxylase, insulinoma-associated protein 2 and zinc transporter-8 antibodies) were measured in the serum of participants who attended the 2011-2013 Pittsburgh Epidemiology of Diabetes Complications study follow-up examination (n=177, mean age 51 years, diabetes duration 43 years).

RESULTS

Prevalences of islet autoantibodies were: glutamic acid decarboxylase, 32%; insulinoma-associated protein 2, 22%; and zinc transporter-8, 4%. Positivity for each islet autoantibody was associated with older age at diabetes onset (glutamic acid decarboxylase antibodies, P=0.03; insulinoma-associated protein 2 antibodies, P=0.001; zinc transporter-8 antibodies, P<0.0001). Older age at onset was also associated with an increasing number of autoantibodies (P = 0.001). Glutamic acid decarboxylase antibody positivity was also associated with lower HbA_1c (P = 0.02), insulinoma-associated protein 2 antibody positivity was associated with lower prevalence of severe hypoglycaemic episodes (P=0.02) and both distal and autonomic neuropathy (P=0.04 for both), and zinc transporter-8 antibody positivity was associated with higher total and LDL cholesterol (P=0.01). No association between autoantibody positivity and C-peptide was observed.

CONCLUSIONS

The strong association between islet autoantibody positivity and older age at type 1 diabetes onset supports the hypothesis of a less aggressive, and thus more persistent, immune process in those with older age at onset. This observation suggests that there may be long-term persistence of heterogeneity in the underlying autoimmune process.

[Ovarian Sertoli-Leydig cell tumors: DICER1 hotspot mutations and associated clinicopathological features]

Objective: To investigate DICER1 hotspot mutations in ovarian Sertoli-Leydig cell tumor (SLCT) and its associated clinicopathological features. Methods: Forty-three SLCTs and 40 other sex cord-stromal tumors (SCSTs) diagnosed between 2010 and 2017 at Fudan University Shanghai Cancer Center were examined for somatic DICER1 hotspot mutations by Sanger sequencing. The associations between mutation status and clinicopathological features, including patient age, tumor differentiation and recurrence, were analyzed. Results: Somatic DICER1 mutations were found in 51% (22/43) of SLCTs, while none in the other 40 SCSTs. The most common mutation of DICER1 was p.D1709N in exon 24 (41%, 9/22) and the second most common mutation of DICER1 was p.E1813K in exon 25 (14%, 3/22). A novel frameshift mutation (c.5464delG, p.M1837fs*16) was identified in one SLCT with microcystic pattern. Mutations were more likely to occur in patients under forty years of age (P=0.046), whereas no significant associations were found between DICER1 mutations and clinical symptoms, morphology or tumor recurrence. Conclusions: Somatic DCIER1 hotspot mutations are specifically found in SLCT and may serve as an ancillary marker in differential diagnosis of SLCT from other SCST. The mutations occur more often in young patients (<40 years old). Additional studies are warranted to examine the associations between DICER1 mutations and clinicopathological features and prognosis of SLCT.

AB0474 CAROTID CONTRAST ENHANCED ULTRASOUND IN CASES OF TAKAYASU ARTERITIS COMPLICATED WITH BEHCET’S DISEASE

Background:

Carotid contrast enhanced ultrasound (CEUS) is used for diagnosis and activity determination of patients with Takayasu’s arteritis (TA). However, very little is known about the carotid CEUS features of TA complicated with Behcet’s disease (BD).

Objectives:

This study reports the carotid CEUS features in cases of TA complicated with BD (TBD).

Methods:

A total of 10 carotid CEUS examinations were performed on 4 patients of TBD. 10 TA patients complicated with no rheumatoid disease were included as control group. For each carotid artery lesion, the carotid CEUS features was graded as follows: Grade 0, artery wall shows no microbubbles, Grade 1, artery wall shows limited or moderate microbubbles, Grade 2, artery wall shows severe microbubbles.

Results:

2/10 patients in TBD group has oral ulcer during the CEUS examination, while all the other patients included in our study showed no clinical symptoms related to active TA or BD. The carotid wall thickness was greater of CEUS grade 2 than grade 1 in both group(TBD: 2.62±0.74mm vs 1.66±0.22mm,p=0.001; TA:1.84±0.31mm vs 1.53±0.5mm,p=0.136). The carotid wall thickness was significantly greater in TBD group than TA group, but there was no significant differences between the two groups in clinical data and CEUS grade (table 1).

Table 1.

Clinical data and carotid CEUS features of both groups

TBDTApAge (year)32.5±3.4430.5±9.20.487Male320.605ESR (mm/h)4(2, 10)7(3.5, 11)0.406CRP (mg/L)6.42(0.55, 15.38)0.58(0.44, 5.05)0.168Wall thickness (mm)2.10±0.701.67±0.440.030CEUS grade 29120.527

Conclusion:

This study first shows carotid CEUS features in cases of TA complicated with BD, which may help with the comprehensive treatments of the disease.

Disclosure of Interests: :

None declared

1135 Longer And More Frequent Naps Predict Incident Alzheimer’s Dementia In Community-based Older Adults

Introduction

Excessive napping duration has been associated with cognitive decline. The effect of napping frequency is less understood, and little is known about the development of Alzheimer’s dementia associated with napping. We tested whether longer or more frequent naps in the elderly are linked to the development of incident Alzheimer’s dementia.

Methods

We studied 1,180 older adults (age: 81.0±7.3 [SD]) in the Rush Memory and Aging Project who have been followed for up to 14 years. Motor activities of up to 10 days were recorded at baseline to assess napping characteristics objectively. We defined daytime napping episodes as motor activity segments between 10AM and 7PM with continuous zero-activity for ≥10min but &lt;1h (to avoid off-wrist periods). Segments that were &lt;5min apart were merged. Alzheimer’s dementia diagnosis was determined using the criteria of the National Institute of Neurological and Communicative Disorders and Strone and the Alzheimer’s Disease and Related Disorders Association. Cox proportional hazards models were performed to examine the associations of daily napping duration and frequency with incident AD.

Results

Of 1,180 non-demented participants at baseline (including 264 with mild cognitive impairment), 277 developed Alzheimer’s dementia within 5.74±3.36 years. On average, participants napped for 38.3±1.0 (SE) min and1.56±0.04 (SE) times per day at baseline. After adjustment for age, sex, and education, every 30-min increase in daily napping duration was associated with a 20% increase in the risk of incident AD (95% confidence interval [CI]: 9%-31%; p=0.0002). One more nap per day was associated with a 19% increase in the risk of AD (95% CI: 8%-30%; p=0.0003). These associations remained after further adjustment for total sleep time.

Conclusion

Longer and more frequent daytime naps predict a higher risk of incident Alzheimer’s dementia. Future studies are needed to examine specific underlying mechanisms.

Support

This work was supported by NIH grants RF1AG064312, RF1AG059867, R01AG017917, and R01AG56352.

Clinical characteristics of lip infantile haemangiomas and main risk factors for ulceration: an 8-year retrospective study of 69 Chinese infants

BACKGROUND

Infantile haemangiomas (IHs) involving the lip are of special concern because of the susceptibility of complications, including ulceration, obstruction and disfigurement. The available data for the relationship between their clinical characteristics and ulcerations are limited.

OBJECTIVES

To describe the clinical characteristics of lip IHs and to evaluate the main risk factors for ulceration.

METHODS

A retrospective study was designed that included infants with lip IHs during an 8-year period, the clinical data of participants were collected, and univariable and multivariable logistic models were used to determine the relationships between the clinical characteristics of lip IHs and ulcerations. Location, size and type were investigated as potential independent factors influencing the development of ulceration.

RESULTS

A total of 69 lip IHs were identified including 40 girls and 29 boys. Ulcerations were found in 37 (53.6%) lip IHs. Lip haemangiomas experiencing ulceration had a mean size (SD) of 3.49 (2.82) cm² compared with 1.08 (0.96) cm² for those without ulceration. Twenty-eight (52.8%) of the 53 localized haemangiomas and 9 (56.3%) of the 16 segmental haemangiomas experienced ulcerations. Univariable analyses of all investigated factors revealed significant associations of location and size with increased risk of ulceration, and these significant associations remained after adjusting for sex and age [OR 8.61 (95% CI, 2.24-33.13) and 2.62 (95% CI, 1.46-4.72), respectively]. The duration before ulceration was between 4 and 70 days after the occurrence of lip IHs, with a median of 28 (19.41) days. Most ulcers occurred within 45 days of IH occurrence.

CONCLUSIONS

Ulceration is a common complication of lip IHs at an earlier stage. A swollen with pale or bright crimson appearance of the lip IH surface could be an important signal of subsequent ulceration. Location of the IH on the lower lip and lip IH size are risk factors for the occurrence of ulceration.

[Application of endoscopic tattooing with carbon nanoparticlet in the treatment for advanced colorectal cancer]

Objective: To explore the application of endoscopic tattooing with carbon nanoparticles in the treatment of advanced colorectal cancer (ACRC). Methods: A randomized controlled study was used. Inclusion criteria: (1) age more than 18 years old, and colorectal cancer was found for the first time and confirmed by colonoscopy and biopsy; (2) advanced colorectal cancer (preoperative TNM stage of T3/N1 or above, local unresectable lesion, M1 stage and simultaneously resectable metastatic lesion), and patients agreed to receive neoadjuvant therapy; (3) advanced colorectal cancer (TNM stage of T3/N1 or above) with simultaneous unresectable metastatic lesion, and patients refused operation and consented to chemoradiotherapy. Patients with previous abdominal surgery history, radiotherapy and chemotherapy history, urgent need for surgery or endoscopic stent placement and those with severe allergic constitution were excluded. Based on the above criteria, 120 patients diagnosed with ACRC in No.900 Hospital of the Joint Logistics Team from January 2016 to December 2017 were prospectively enrolled and randomly divided into tattoo group and non-tattoo group by random number table method. Tattoo group were tattooed within 1-7 days before chemoradiotherapy. The labeling location of the lesions: (1) if the colonoscopy could pass smoothly, 4 points were injected into the intestinal wall of the both opposite sides 1 cm cephalad and caudad of the tumor; (2) if the colorectal cavity was severely narrow and the colonoscopy could not pass, only 4 points were injected in 4 quadrants at 1 cm caudad of the tumor. Each injection point was injected with 0.1 ml carbon nanoparticles, and the size of the tumor was measured according to the range of carbon nanoparticles staining. The efficacy was evaluated after 8 weeks of chemoradiotherapy. Patients who were defined to be suitable for operation underwent operation 6 weeks after chemoradiotherapy. The following parameters were compared between two groups: lesion identification time, operation time, blood loss, distance from lesion to distal margin, the rate of first positive margin and the rate of anal sphincter preservation (rectal cancer). Among patients who had been evaluated as having no indication for surgery, those who were effective in chemoradiotherapy continued to receive chemotherapy in the original regimen; if the treatment failed, the chemotherapy regimen was replaced, and the efficacy was finally evaluated after six months [referring to the revised RECIST guidelines (version 1.1)]. Results: Three patients withdrew from this study, and 117 patients were enrolled in this study finally, including 59 cases in tattoo group and 58 cases in the non-tattoo group. There were no significant differences in baseline data between two groups (all P>0.05). All the patients had slight adverse reactions of radiotherapy and chemotherapy before operation, and could tolerate after symptomatic management without interruption of treatment. All the patients in the tattoo group had no discomfort such as fever, abdominal pain, abdominal distention, hematochezia, etc. and the intestinal mucosa could be seen clearly with black staining after being tattooed. A total of 77 patients were evaluated with surgical indications, including 39 cases in the tattoo group (tattoo-operable) and 38 cases in the non-tattoo group (non-tattoo-operatable). There were no significant differences in baseline data between the two groups (all P>0.05). Forty patients without operation indications continued chemoradiotherapy, including 20 cases in tattoo group (tattoo-inoperable) and 20 cases in non-tattoo group (non-tattoo-inoperable), whose differences in baseline data between the two groups were not significant as well (all P>0.05). No obvious edema, necrosis or abscess were found in the tattooed segments and the black spots could be seen quickly and clearly on the serosa of rectum in tattoo-operable patients. As compared to non-tattoo group, tattoo group had significantly shorter lesion identification time [(3.4±1.4) minutes vs. (11.8±3.4) minutes, t=-14.07,P<0.001], shorter operation time [(155.7±44.5) minutes vs. (177.2±30.2) minutes, t=-2.48,P=0.015], less blood loss [(101.3±36.7) ml vs.(120.2±38.2) ml, t=-2.22,P=0.029], shorter distance from lesion to distal margin [(3.7±1.0) cm vs. (4.6±1.7) cm, t=-2.20, P=0.034], while tattoo group had slightly higher rate of anal sphincter preservation [66.7%(16/24) vs. 45.5%(10/22), χ(2)=2.10,P=0.234] and lower rate of first positive resection margin [0 vs. 4.5%(1/22), χ(2)=0.62,P=0.480], but their differences were not significant. There were no significant differences in the degree of tumor differentiation and TNM stage between two groups. Patients without operative indication were evaluated for efficacy of chemoradiotherapy again after half a year. One case of complete response (CR), 8 of partial response (PR), 10 of stable disease (SD) and 1 of progressive disease (PD) were found and the improvement rate was 45.0% (9/20) in tattoo-inoperable patients. No case of CR, 6 of PR, 11 of SD and 3 of PD were found and the improvement rate was 30.0% (6/20) in non-tattoo-inoperable patients. There was no significant difference in the improvement rate between the two groups (P=0.514). Conclusions: Endoscopic tattooing with carbon nanoparticles injection is safe and reliable for colorectal tumor positioning. It can assist rapid detection of lesions during surgery after neoadjuvant treatment, perform accurate resection, significantly shorten the operation time and reduce surgical trauma; can assist colonoscopy accurately to measure the size of the lesions before and after chemoradiotherapy, and increase the means of assessing the efficacy to guide the follow-up treatment plan. This technique is worth clinical promotion and application.