Development and validation of an online calculator to predict the pathological nature of colorectal tumors

BACKGROUND

No single endoscopic feature can reliably predict the pathological nature of colorectal tumors (CRTs).

AIM

To establish and validate a simple online calculator to predict the pathological nature of CRTs based on white-light endoscopy.

METHODS

This was a single-center study. During the identification stage, 530 consecutive patients with CRTs were enrolled from January 2015 to December 2021 as the derivation group. Logistic regression analysis was performed. A novel online calculator to predict the pathological nature of CRTs based on white-light images was established and verified internally. During the validation stage, two series of 110 images obtained using white-light endoscopy were distributed to 10 endoscopists [five highly experienced endoscopists and five less experienced endoscopists (LEEs)] for external validation before and after systematic training.

RESULTS

A total of 750 patients were included, with an average age of 63.6 ± 10.4 years. Early colorectal cancer (ECRC) was detected in 351 (46.8%) patients. Tumor size, left semicolon site, rectal site, acanthosis, depression and an uneven surface were independent risk factors for ECRC. The C-index of the ECRC calculator prediction model was 0.906 (P = 0.225, Hosmer–Lemeshow test). For the LEEs, significant improvement was made in the sensitivity, specificity and accuracy (57.6% vs 75.5%; 72.3% vs 82.4%; 64.2% vs 80.2%; P < 0.05), respectively, after training with the ECRC online calculator prediction model.

CONCLUSION

A novel online calculator including tumor size, location, acanthosis, depression, and uneven surface can accurately predict the pathological nature of ECRC.

PTPMT1 regulates mitochondrial death through the SLC25A6-NDUFS2 axis in pancreatic cancer cells

Pancreatic ductal adenocarcinoma is a highly malignant cancer with poor prognosis, for which effective therapeutic strategies are urgently needed. The dual-specificity phosphatase PTPMT1 is localized in mitochondria and highly expressed in various cancers. Here, we investigated the function of PTPMT1 in pancreatic ductal adenocarcinoma. We inhibited its expression in pancreatic cancer cell lines using siRNAs or the specific PTPMT1 inhibitor alexidine dihydrochloride and observed that PTPMT1 silencing in pancreatic cancer cell lines drastically reduced cell viability, caused mitochondrial damage, and impaired mitochondrial function. Co-immunoprecipitation analysis demonstrated that PTPMT1 could interact with SLC25A6 and NDUFS2, indicating that it may modulate mitochondrial function via the SLC25A6-NDUFS2 axis. Collecively, our data highlight PTPMT1 as an important factor in pancreatic ductal adenocarcinoma and a potential therapeutic target.

CO2 or air cholangiography reduces the risk of post-ERCP cholangitis in patients with Bismuth type IV hilar biliary obstruction

Background

Endoscopic biliary stenting by endoscopic retrograde cholangiopancreatography (ERCP) is the most common form of palliation for malignant hilar obstruction. However, ERCP in such cases is associated with a risk of cholangitis. The incidence of post-ERCP cholangitis is particularly high in Bismuth type IV hilar obstruction, and this risk is further increased when the contrast injected for cholangiography is not drained. The present study aims to compare the incidence of cholangitis associated with the use of a contrast agent, air and CO₂ for cholangiography in type IV hilar biliary lesions.

Methods

The clinical data of consecutive 70 patients with type IV hilar obstruction, who underwent ERCP from October 2013 to November 2017, were retrospectively analyzed. These patients were divided into three groups based on the agent used for cholangiography: group A, contrast (n = 22); group B, air (n = 18); group C, CO₂ (n = 30). These three methods of cholangiography were chronologically separated. Prior to the ERCP, MRCP was obtained from all patients to guide the endoscopic intervention.

Results

At baseline, there was no significant difference in terms of the patient’s age, gender, symptoms and liver function tests among the three groups (P > 0.05). The complication rates were significantly higher in group A than in groups B and C (63.6% vs. 26.7 and 27.8%, P < 0.05). The incidence of post-ERCP cholangitis was significantly higher in group A (P < 0.05), while the incidence of post-ERCP pancreatitis and bleeding were similar in the three groups. After the ERCP, the mean hospital stay was shorter in groups B and C, when compared to group A (P < 0.05). However, there was no significant difference in the 30-day mortality rate among the three groups (P > 0.05). Furthermore, there was no significant difference between groups B and C in terms of primary end points.

Conclusion

CO₂ or air cholangiography during ERCP for type IV hilar obstruction is associated with reduced risk of post-ERCP cholangitis, when compared to conventional contrast agents.

Malignant glomus tumor of the intestinal ileum with multiorgan metastases: A case report and review of literature

BACKGROUND

Glomus tumors (GTs) are rare mesenchymal neoplastic lesions derived from cells of the glomus body. GTs rarely occurs in the visceral organs, where there may be few or no glomus bodies, and the majority of GTs are benign, rarely demonstrating aggressive or malignant behavior and histological features.

CASE SUMMARY

We report a patient with malignant GTs of the intestinal ileum with multiorgan metastases who was admitted due to moderate anemia. Capsule endoscopy revealed a bleeding mass in the intestinal ileum, and the patient underwent segmental ileal resection through laparoscopic surgery. The histopathological and immunohistochemical diagnoses were consistent with malignant GT. Long-term follow-up showed that the GT had metastasized to multiple organs such as the colon, brain, and possibly the lung.

CONCLUSION

This case was characterized by the highest degree of malignancy and by multiorgan metastases, and it was the first case of intestinal GT uncovered by capsule endoscopy.

Molecular defect-containing bilayer graphene exhibiting brightened luminescence

The electronic structure of bilayer graphene can be altered by creating defects in its carbon skeleton. However, the natural defects are generally heterogeneous. On the other hand, rational bottom-up synthesis offers the possibility of building well-defined molecular cutout of defect-containing bilayer graphene, which allows defect-induced modulation with atomic precision. Here, we report the construction of a molecular defect-containing bilayer graphene (MDBG) with an inner cavity by organic synthesis. Single-crystal x-ray diffraction, mass spectrometry, and nuclear magnetic resonance spectroscopy unambiguously characterize the structure of MDBG. Compared with its same-sized, defect-free counterpart, the MDBG exhibits a notable blue shift of optical absorption and emission, as well as a 9.6-fold brightening of its photoluminescence, which demonstrates that a single defect can markedly alter the optical properties of bilayer graphene.

[Niches and interspecific association of dominant shrimp species in the offshore waters of southern Zhejiang Province, China]

Based on data from November of 2015 (autumn), February (winter), May (spring), and August (summer) of 2016 in the offshore waters of southern Zhejiang Province, the relationships between major shrimps species were examined by niche breadth, niche overlap, variance ratio, chi-square test, association coefficient and species pair co-occurrence percentage. The results showed that temporal niche breadth of Atypopenaeus stenodactylu was the largest, spatial niche breadth of Solenocera crassicornis was the largest, and A. stenodactylu had the largest spatio-temporal niche breadth. The temporal niche overlap between Parapenaeus fissuroides and Parapenaeopsis tenella was the highest. The spatial niche overlap between Solenocera koelbeli and Penaeus chinensis, P. fissuroides and Heterocarpoides laevicarina were the highest. The spatio-temporal niche overlap between S. koelbeli and P. chinensis was the highest. The analysis of variance ratio showed that the main shrimp species were significantly positively correlated. Positive correlation existed in 13 pairs (χ²≥3.841). Results from the association coefficient (AC) and co-occurrence percentage (PC) indicated that the interspecific association tended to be positive. Our results provide supports for exploring niche breadth and niche overlap of major shrimp species and improving niche differentiation.

MicroRNA-26a inhibits proliferation by targeting high mobility group AT-hook 1 in breast cancer

OBJECTIVES

To investigate the crucial role of miR-26a in breast cancer and to validate whether miR-26a could regulate proliferation of breast cancer cells by targeting high mobility group AT-hook 1 (HMGA1).

METHODS

Reverse transcription-polymerase chain reaction (RT-PCR) was used to quantify the expression levels of miR-26a in breast cancer and adjacent non-cancerous breast tissues. MTT, cell migration and invasion assay were carried out to characterize the miR-26a function. Finally, to validate the target gene of miR-26a, luciferase reporter assay was employed, followed by RT-PCR and Western blot confirmation.

RESULTS

Compared with normal tissues, a significant down-regulation of miR-26a expression was observed in breast cancer tissues (P=0.002). miR-26a suppresses MDA-MB-231 and Mcf-7 breast cancer cell lines proliferation and motility. The luciferase activity was significantly decreased after co-transfection with psiCHECK-2/HMGA1 3'-UTR and miR-26a mimics in comparison with control cells, and qRT-PCR and Western blotting analysis found that HMGA1 expression at the mRNA and protein levels decreased in the miR-26a mimic-treatment group relative to NC. MTT assay showed that down regulation of HMGA1 by siRNA could significantly enhance the tumor-suppressive effect of miR-26a (P < 0.05).

CONCLUSIONS

The results of the present study indicate that miR-26a may be associated with human breast carcinogenesis, which inhibits tumor cell proliferation by targeting HMGA1.

Film cooling performance on curved walls with compound angle hole configuration

In order to explore the effect of compound angle holes on film cooling over a convex wall and a concave wall, the present study adopts the transient liquid crystal thermography for conducting the film cooling measurement on simple hole and expanded-hole configurations. Two compound angles of 0 and 45 deg are tested at an elevated mainstream turbulence condition (Tu) of 3.8%. The test pieces have the different radius of curvature (2r/D) of 92.5 on convex and 86.5 on concave, and the same pitch to diameter ratio (P/D) of 3 on both convex and concave walls. All measurements were conducted under the mainstream Reynolds number (Re(d)) of 1700 on convex and 2300 on concave with the density ratio between coolant and mainstream (rho c/rho m) of 0.98. In current study, the effect of blowing ratio (M) on film cooling performance is investigated by varying the range of blowing ratio from 0.5 and 2.0. The present measured results show that the forward-expanded hole injection provides better surface protection than the simple hole injection. As far as the injection angle is concerned, compound angle injection provides higher film effectiveness than simple angle injection. However, the forward-expanded hole in injection (beta = 0 degree) has the best performance on both convex and concave surfaces.