Establishment and validation of a computer-assisted colonic polyp localization system based on deep learning

BACKGROUND

Artificial intelligence in colonoscopy is an emerging field, and its application may help colonoscopists improve inspection quality and reduce the rate of missed polyps and adenomas. Several deep learning-based computer-assisted detection (CADe) techniques were established from small single-center datasets, and unrepresentative learning materials might confine their application and generalization in wide practice. Although CADes have been reported to identify polyps in colonoscopic images and videos in real time, their diagnostic performance deserves to be further validated in clinical practice.

AIM

To train and test a CADe based on multicenter high-quality images of polyps and preliminarily validate it in clinical colonoscopies.

METHODS

With high-quality screening and labeling from 55 qualified colonoscopists, a dataset consisting of over 71000 images from 20 centers was used to train and test a deep learning-based CADe. In addition, the real-time diagnostic performance of CADe was tested frame by frame in 47 unaltered full-ranged videos that contained 86 histologically confirmed polyps. Finally, we conducted a self-controlled observational study to validate the diagnostic performance of CADe in real-world colonoscopy with the main outcome measure of polyps per colonoscopy in Changhai Hospital.

RESULTS

The CADe was able to identify polyps in the test dataset with 95.0% sensitivity and 99.1% specificity. For colonoscopy videos, all 86 polyps were detected with 92.2% sensitivity and 93.6% specificity in frame-by-frame analysis. In the prospective validation, the sensitivity of CAD in identifying polyps was 98.4% (185/188). Folds, reflections of light and fecal fluid were the main causes of false positives in both the test dataset and clinical colonoscopies. Colonoscopists can detect more polyps (0.90 vs 0.82, P < 0.001) and adenomas (0.32 vs 0.30, P = 0.045) with the aid of CADe, particularly polyps < 5 mm and flat polyps (0.65 vs 0.57, P < 0.001; 0.74 vs 0.67, P = 0.001, respectively). However, high efficacy is not realized in colonoscopies with inadequate bowel preparation and withdrawal time (P = 0.32; P = 0.16, respectively).

CONCLUSION

CADe is feasible in the clinical setting and might help endoscopists detect more polyps and adenomas, and further confirmation is warranted.

Perioperative analgesia with parecoxib sodium improves postoperative pain and immune function in patients undergoing hepatectomy for hepatocellular carcinoma

RATIONALE, AIMS, AND OBJECTIVES

Acute postoperative pain can result in immune dysfunction, which can be partly mitigated by efficient pain management. Opioids that have been widely applied to analgesia have been shown to suppress immune function, which has a negative impact on the treatment of patients with cancer. This study investigated the effects of perioperative fentanyl analgesia alone or in combination with parecoxib sodium on postoperative pain, immune function, and prognosis in patients undergoing hepatectomy of hepatocellular carcinoma (HCC).

METHODS

A total of 80 patients scheduled for hepatectomy between October 2013 and August 2014 were included. Patients were randomly divided into two groups (n = 40) and allocated to receive parecoxibsodium 40 mg (group P) or placebo (group C) 30 minutes before induction of anaesthesia, followed by 40 mg every 12 hours for 48 hours after the operation. All patients had access to patient-controlled analgesia with intravenous fentanylpostoperatively. Venous blood samples were collected at the following time points: 30 minutes before induction of anaesthesia (T0), the end of the surgery (T1), 24 hours after surgery (T2), and 72 hours after surgery (T3). The percentages of CD3+, CD4+, CD8+, CD4+/CD8+ T cells, and CD3+CD16+CD56+ (NK) cells at these time points were quantified by flow cytometry (FCM).Visual analogue scale (VAS) scores, total fentanyl consumption, and adverse effects were recorded. The prognostic differences in overall survival (OS) and disease-free survival (DFS) between the two groups was also investigated.

RESULTS

For both groups, the percentages of CD3+, CD4+ T cells, and the ratio of CD4+/CD8+ significantly decreased at T1 and T2 (P < .05). The percentages of CD3+ T cells were significantly lower in group C than that in group P at T2 (P < .05). In group C, the amount of CD3+ T cells was lower at T3 compared with T0 (P < .05). The percentages of NK cells significantly decreased at T1 in both groups (P < .05). The percentages of NK in group P were recovered nearly to baseline (T0) at T2, which was higher than that of group C (P < .05). In group C, the percentages of NK cells have not recovered nearly to baseline at T3 compared with T0 (P < .05). VAS scores at rest and on cough in group P were significantly lower than those in group C at 2, 6, 12, and 24 hours after operation (P < .05), and there were no significant differences in VAS scores between the two groups at 48 hours after surgery (P > .05). There were no significant differences regarding the incidence of adverse effects between the two groups (P > .05). Kaplan-Meier analysis indicated that the DFS time in group P was significantly longer than in group C (19.0 months, 95% confidence interval [CI], 9.8-28.2 vs 14.0 months, 95% CI, 8.1-19.9; P < .05). There was no significant difference in OS time (36.0 months, 95% CI, 13.4-58.9 vs 14.0 months, 95% CI, 10.6-25.4; P > .05) between two groups.

CONCLUSIONS

The present study indicated that perioperative analgesia of parecoxib sodium combined with patient-controlled analgesic fentanyl resulted in better preserved immune function with enhancement of the analgesic efficacy to fentanyl alone of HCC patients undergoing hepatectomy and helped postpone postoperative tumour recurrence.

Flurbiprofen axetil for postoperative analgesia in upper abdominal surgery: a randomized, parallel controlled, double-blind, multicenter clinical study

PURPOSE

To investigate the efficacy and safety of flurbiprofen axetil in postoperative analgesia in upper abdominal surgery.

METHODS

This was a multicenter, randomized, positive drug parallel controlled double-blind clinical study. Patients undergoing upper abdominal surgery were randomly divided to receive flurbiprofen axetil or tramadol. The VAS pain scores at rest and on coughing (pulmonary function training) were assessed immediately before drug usage (T1) to evaluate the efficacy of postoperative analgesia. Repeat assessment of the VAS was performed after T1. The timing of the recovery of the gastrointestinal function and the preoperative and postoperative IL-6, cortisol, and blood glucose levels were recorded as secondary endpoints. Vital signs and the occurrence of adverse reactions were evaluated for the assessment of safety.

RESULTS

A total of 240 patients were enrolled in the current study; 119 used flurbiprofen axetil for postoperative analgesia. The VAS scores at rest and on coughing did not differ between the two groups to a statistically significant extent (P > 0.05). However, the reduction of the VAS score at rest in the flurbiprofen axetil group was greater than that in the tramadol group at 4-24 h after T1. The reduction of the VAS score on coughing at 8 h after T1 was greater in the flurbiprofen axetil group. The incidence of adverse reactions was significantly lower in the flurbiprofen axetil group, with only one adverse reaction recorded. In contrast, 18 adverse reactions were reported in the tramadol group.

CONCLUSION

Flurbiprofen axetil showed superior efficacy to tramadol in early postoperative analgesia after upper abdominal surgery. Flurbiprofen axetil was associated with a significantly lower incidence of adverse reactions in comparison to tramadol.

[Influential factors for failure of enhanced recovery after surgery from hepatectomy for hepatocellular carcinoma and the establishment of risk prediction model]

Objective: To investigate the influential factors for failure of enhanced recovery after surgery(ERAS) from hepatectomy for hepatocellular carcinoma(HCC) patients and then to establish a risk prediction model. Methods: The relevant clinical data of 180 patients with HCC undergoing hepatectomy at Department of Hepatic Surgery, Affiliated Provincial Hospital, Anhui Medical University from January 2016 to June 2017 were analyzed retrospectively.There were 149 male patients and 31 female patients aging of (56.5±11.0)years(from 33 to 84 years old). The factors affecting postoperative failure of ERAS of HCC patients were identified by univariate and multivariate analyses, and then, all the obtained factors and their statistical values were used to establish the risk prediction model. Results: A total of 23 patients failed in the ERAS protocol(12.8%). The preoperative total bilirubin (TBIL), alanine aminotransferase(ALT) and amount of intraoperative bleeding were independent risk factors for failure of ERAS from hepatectomy(all P<0.05). The obtained risk prediction model was presented as follows: risk coefficient(R)=0.114×(TBIL)+ 0.082×(ALT)+ 0.008×(amount of intraoperative bleeding). At the cut of value of R=7.90, the area under the ROC curve of this model for predicting failure of ERAS was 0.866(95%CI: 0.788-0.945, P<0.01), with the sensitivity and specificity of 69.6% and 91.1%, respectively.External validation results indicated that the scoring system had good differential ability(area under the ROC curve=0.889, 95%CI: 0.811-0.967, P<0.01). Conclusions: Higher level of preoperative TBIL(>21 μmol/L) and ALT(>50 U/L) and the larger amount of intraoperative bleeding (more than 400 ml) are independent risk factors for failure of ERAS inpatients undergoing hepatectomy for HCC and the established prediction model may have certain value for risk assessment.

Low levels of tumor suppressor candidate 3 predict poor prognosis of patients with hepatocellular carcinoma

Purpose

The tumor suppressor candidate 3 (TUSC3) has been considered to be closely associated with the occurrence, development and invasion of various malignant tumors. However, the expression of TUSC3 in hepatocellular carcinoma (HCC) tissues remains ambiguous. The purpose of this research was to investigate the expression of TUSC3 in HCC tissues and analyze the relationship between TUSC3 levels and clinicopathological characteristics and prognosis of HCC patients.

Materials and methods

Immunohistochemistry was used to detect the expression of TUSC3 in HCC and the corresponding para-cancerous tissues from 92 samples of HCC patients. mRNA and protein expression levels of TUSC3 were evaluated by quantitative real-time polymerase chain reaction (qRT-PCR) and Western blot assays in 25 paired HCC and corresponding adjacent nontumor tissues. Furthermore, statistical analysis was applied to evaluate the correlation between TUSC3 level and the clinicopathological features and prognosis of HCC patients.

Results

Immunohistochemical assay indicated that the expression of TUSC3 was significantly lower in HCC tissues when compared with the corresponding para-cancerous tissues (χ²=11.512, P=0.001). The analysis of clinicopathological characteristics showed that low expression of TUSC3 in HCC tissues was significantly associated with Edmondson grade, Barcelona Clinic Liver Cancer stage and tumor size (P=0.008, 0.009 and 0.020, respectively). Univariate analysis showed that the expression of TUSC3 was strongly correlated with overall survival (OS) and disease-free survival (DFS) after radical surgery in HCC patients (P<0.001, P<0.001, respectively). Multivariate analysis revealed that the TUSC3 level was an independent risk factor for OS and DFS in HCC patients (P=0.001, P<0.001, respectively). Results of qRT-PCR and Western blot assays indicated that the level of TUSC3 in HCC tissues was significantly lower than that in the corresponding adjacent noncancerous tissues (P<0.01, P<0.001).

Conclusion

The expression of TUSC3 in HCC was significantly downregulated and was correlated with tumor progression and prognosis, which could be used as an independent predictor of prognosis in HCC patients.

Metal induced self-assembly of designed V-shape protein into 2D wavy supramolecular nanostructure

In order to understand and imitate the more complex bio-processes and fascinating functions in nature, protein self-assembly has been studied and has attracted more and more interest in recent years. Artificial self-assemblies of proteins have been constructed through many strategies. However, the design of complicated protein self-assemblies utilizing the special profile of building blocks remains a challenge. We herein report linear and 2D nanostructures constructed from a V shape SMAC protein and induced by metal coordination. Zigzag nanowires and wavy 2D nanostructures have been demonstrated by AFM and TEM. The zigzag nanowires can translate to a 2D nanostructure with an excess of metal ions, which reveals the step by step assembly process. Fluorescence and UV/Vis spectra have also been obtained to further study the mechanism and process of self-assembly. Upon the protein nanostructure, fluorescence resonance energy transfer (FRET) could also be detected using fluorescein modified proteins as building blocks. This article provides an approach for designing and controlling self-assembled protein nanostructures with a distinctive topological morphology.

Three-dimensional ultrasound-assisted popliteal catheter placement revealing aberrant anatomy: implications for block failure

BACKGROUND

The current means of introducing continuous sciatic catheters include nerve stimulation, with or without catheter stimulation techniques. More recently, ultrasound has been utilized to facilitate catheter placement.

METHODS

This case represents a stimulating catheter-guided continuous block facilitated by three-dimensional ultrasound, which revealed aberrant anatomy with proximal and wide bifurcation of the sciatic nerve with implications for block failure.

RESULTS

Before ultrasound imaging secondary failures were attributed to catheter misplacement or dislodgement.

CONCLUSION

Because of this case observation, our current practice is to use ultrasound confirmation of the bifurcation of the nerve of all popliteal catheter placements, particularly catheters placed in patients having ambulatory procedures to prevent secondary failure of catheters at home.

Update on ropivacaine

Long-acting local anaesthetics are primarily used in the practice of anaesthesia, particularly in regional anaesthesia and analgesia. Ropivacaine is a new long-acting local anaesthetic that has been the focus of interest because of its increased cardiovascular safety compared with bupivacaine. Other advantages of ropivacaine over bupivacaine include a greater sensorimotor differential block and shorter elimination half-life (t(1/2)), with a lower potential for accumulation. The most important attribute of ropivacaine, however, is its increased margin of safety compared with bupivacaine when given in equal doses. Many post-marketing studies have focused on the comparisons of efficacy in blocks and toxicity profiles of bupivacaine versus ropivacaine. Recent animal toxicity studies confirm the results of original studies showing that ropivacaine has less cardiovascular toxicity than bupivacaine with respect to direct myocardial depression, success of resuscitation and arrhythmogenic potential when given in equal doses. Reduced cardiotoxicity may be a distinct characteristic of ropivacaine. A review of current literature suggests that, at clinically relevant doses, ropivacaine provides the lowest potential risk of cardiotoxicity for inadvertent intravascular injection. Studies are currently under way comparing ropivacaine with levobupivacaine, the latest addition to the group of long-acting local anaesthetics.

[Protective effect of ONO-1078, a leukotriene antagonist, on focal cerebral ischemia in mice]

AIM

To determine whether ONO-1078 [pranlukast, 4-oxo-8-[p-(4-phenylbutyloxy) benzoyl-amino]-2-(tetrazol-5-yl)-4H-1-benzopyran hemihydrate], a potent leukotriene antagonist, has protective effect on focal cerebral ischemia in mice.

METHODS

Focal cerebral ischemia was induced by permanent middle cerebral artery (MCA) occlusion in mice. ONO-1078 (0.01, 0.05, 0.10 mg.kg-1), dexamethasone (0.5 mg.kg-1), nimodipine (0.2 mg.kg-1) or saline (control) were injected i.p. once daily for 3 days, and 30 min before MCA occlusion. Twenty-four hours after cerebral ischemia, the neurological scores were evaluated, infarct volumes and areas of the right and left cerebral hemispheres were measured by computer imaging analysis.

RESULTS

ONO-1078, dexamethasone and nimodipine reduced the neurological scores. ONO-1078 and dexamethasone reduced the ratio of right/left hemisphere area, indicating inhibition of brain edema, while nimodipine showed no effect. ONO-1078 dose-dependently reduced infarct size, and dexamethasone and nimodipine showed the same effect.

CONCLUSION

ONO-1078 showed protective effect on focal cerebral ischemia. This may represent a novel approach to the treatment of acute cerebral ischemia.

[Data analysis of 492 times centrifuge examination]

Objective. To sum up the experiences and to find the regularity of centrifuge examinations. Method. The data of nine years of centrifuge examination (from 1988 to 1996) of pilots who suffered from black out or LOC frequently were analyzed. Result. There were totally 492 times centrifuge examinations. First centrifuge examination included 229 pilots, 49 qualified, 180 unqualified. Second centrifuge examination included 263 pilots, 50 qualified, 213 unqualified. The pilots were all male. The average age of first centrifuge examination was 29.27 +/- 4.87 years. Average flying time was 1015.24 +/- 131.89 h. 68.7% of their plane was JJ-6 or above. Conclusion. Most pilots undergoing centrifuge examination these nine years were 26-35 year old, and had flown for 601-1200 h. The planes they flew are mostly high-performance fighter aircraft. Close attention must be paid to pilots under similar condition by the flight surgeon. It is recommended that the special equipment of G-tolerance training should be added to the fighter aircraft units.

Investigation on the effect of selenium on T lymphocyte proliferation and its mechanisms

The effects of selenium on T lymphocyte proliferation and its mechanisms have been investigated. The results showed that selenium is able to enhance lectin-stimulated T lymphocyte proliferation, to increase the production of interleukin 2 (IL-2) by lymphocytes and interleukin 1 (IL-1) by macrophages in the presence of lectin and to augment the response of T lymphoblasts to IL-2 and that of thymocytes to IL-1. The data presented suggest that selenium may be an important modulator for immune response. Selenium might enhance IL-2 production and response through the augmentation of IL-1 production and response, thereby promoting the enhancement of the proliferation and action of T lymphocytes and other immunocompetent cells. Based on these results, we may consider using selenium as an immunological enhancement agent to enhance or recover immune functions of the organism.

Effect of tumor-derived immunosuppressive factor(s) on interleukin 2 and on expression of interleukin 2 receptor

In this paper, we have described the effects of tumor-derived immunosuppressive factor(s) (TDSF) on interleukin 2 (IL-2) production, on IL-2 responsiveness and on the expression of IL-2 receptors. The results showed that TDSF was able to markedly inhibit the production of IL-2 from PHA-stimulated lymphocytes and IL-2-dependent proliferation of activated lymphocytes, and to partially inhibit the expression of IL-2 receptor. These results suggest that inhibiting IL-2 production and responsiveness may be a major mechanism by which TDSF inhibit T lymphocyte proliferation and other immune responses. That TDSF exerted a very potent inhibiting action on IL-2 responsiveness is especially noticeable if we consider using IL-2 as an immunotherapeutic agent. This may be an important reason why treatment of tumor with IL-2 did not yield satisfactory results so far.

Investigation on the inhibitory effect of tumor-derived immunosuppressive factor(s) on T lymphocyte proliferation

Using five tumor cell lines, the effect of tumor-derived immunosuppressive factor(s) (TDSF) on T lymphocyte proliferation and its mechanism have been investigated. It was found that TDSF markedly inhibited PHA-stimulated T lymphocyte proliferation via a noncytotoxic mechanism. The inhibition increased in dose-dependent manner and the maximum inhibition was achieved when the factor was added at the initiation of the culture. When PBMC were preincubated with supernatants of tumor cells for 24 h, washed extensively and then cocultured with freshly prepared PBMC, similar suppressive effects were observed. The above results indicated that the activation of any suppressor cell subgroup may be one of the mechanisms of immunosuppressive action of TDSF.

Biologic characteristics of an immunosuppressive factor derived from a human lung cancer cell line

A 549, a human lung cancer cell line, spontaneously produces a tumor-derived immunosuppressive factor (TDSF) which inhibited PHA-stimulated T lymphocyte proliferation via a noncytotoxic mechanism. The inhibition increased in a dose-dependent pattern. The factor also markedly suppressed production of interleukin (IL-2) by PHA-stimulated lymphocytes and IL 2-dependent proliferation of activated lymphocytes. The fact that TDSF possessed very potent inhibitive action on IL-2 is especially noteworthy if we consider the use of IL-2 as immunotherapeutic agent. The synthesis of the factor was inhibited by mitomycin C, actinomycin D and cycloheximide, indicating that the factor is a genic product of A 549 cells. The factor is chemically a protein with a molecular weight greater than 150 KD and sensitive to extremes of pH, heating to 60 degrees C and trypsin treatment.

Biologic effects of freezing on tissues of the maxillofacial region

An experimental study was done on the effects of freezing on various tissues of the maxillofacial region. After freezing, skin became necrotic, but the wound healed with a flat surface. Blood vessels showed injury of the endothelial cells and thrombosis in the veins. The internal wall of some arteries became thickened, and the lumen was narrowed. Paralysis of the facial nerve occurred immediately after freezing. Function usually recovered several weeks later. Cartilage and bone showed no change in shape after freezing, but the cells were destroyed. New cartilage and bone formation were seen in the later stages.