[Preparation of chitin/hyaluronic acid/collagen hydrogel loaded with mouse adipose-derived stem cells and its effects on wound healing of full-thickness skin defects in rats].

Objective: To prepare the chitin/hyaluronic acid/collagen hydrogel loaded with mouse adipose-derived stem cells and to explore its effects on wound healing of full-thickness skin defects in rats. Methods: The research was an experimental research. Chitin nanofibers were prepared by acid hydrolysis and alkaline extraction method, and then mixed with hyaluronic acid and collagen to prepare chitin/hyaluronic acid/collagen hydrogels (hereinafter referred to as hydrogels). Besides, the hydrogels loaded with mouse adipose-derived stem cells were prepared. Thirty male 12-week-old guinea pigs were divided into negative control group, positive control group, and hydrogel group according to the random number table, with 10 guinea pigs in each group. Ethanol, 4-aminobenzoic acid ethyl ester, or the aforementioned prepared hydrogels without cells were topically applied on both sides of back of guinea pigs respectively for induced contact and stimulated contact, and skin edema and erythema formation were observed at 24 and 48 h after stimulated contact. Adipose-derived stem cells from mice were divided into normal control group cultured routinely and hydrogel group cultured with the aforementioned prepared hydrogels without cells. After 3 d of culture, protein expressions of platelet-derived growth factor-D (PDGF-D), insulin-like growth factor-Ⅰ (IGF-Ⅰ), and transforming growth factor ß1 (TGF-ß1) were detected by Western blotting (n=3). Eight male 8-week-old Sprague-Dawley rats were taken and a circular full-thickness skin defect wound was created on each side of the back. The wounds were divided into blank control group without any treatment and hydrogel group with the aforementioned prepared hydrogels loaded with adipose-derived stem cells applied. Wound healing was observed at 0 (immediately), 2, 4, 8, and 10 d after injury, and the wound healing rate was calculated at 2, 4, 8, and 10 d after injury. Wound tissue samples at 10 d after injury were collected, the new tissue formation was observed by hematoxylin-eosin staining; the concentrations of interleukin-1α (IL-1α), IL-6, IL-4, and IL-10 were detected by enzyme-linked immunosorbent assay method; the expressions of CD16 and CD206 positive cells were observed by immunohistochemical staining and the percentages of positive cells were calculated. The sample numbers in animal experiment were all 8. Results: At 24 h after stimulated contact, no skin edema was observed in the three groups of guinea pigs, and only mild skin erythema was observed in 7 guinea pigs in positive control group. At 48 h after stimulated contact, skin erythema was observed in 8 guinea pigs and skin edema was observed in 4 guinea pigs in positive control group, while no obvious skin erythema or edema was observed in guinea pigs in the other two groups. After 3 d of culture, the protein expression levels of PDGF-D, IGF-I, and TGF-ß1 in adipose-derived stem cells in hydrogel group were significantly higher than those in normal control group (with t values of 12.91, 11.83, and 7.92, respectively, P<0.05). From 0 to 10 d after injury, the wound areas in both groups gradually decreased, and the wounds in hydrogel group were almost completely healed at 10 d after injury. At 4, 8, and 10 d after injury, the wound healing rates in hydrogel group were (38±4)%, (54±5)%, and (69±6)%, respectively, which were significantly higher than (21±6)%, (29±7)%, and (31±7)% in blank control group (with t values of 3.82, 3.97, and 4.05, respectively, Pvalues all <0.05). At 10 d after injury, compared with those in blank control group, the epidermis in wound in hydrogel group was more intact, and there were increases in hair follicles, blood vessels, and other skin appendages. At 10 d after injury, the concentrations of IL-1α and IL-6 in wound tissue in hydrogel group were significantly lower than those in blank control group (with tvalues of 8.21 and 7.99, respectively, P<0.05), while the concentrations of IL-4 and IL-10 were significantly higher than those in blank control group (with tvalues of 6.57 and 9.03, respectively, P<0.05). The percentage of CD16 positive cells in wound tissue in hydrogel group was significantly lower than that in blank control group (t=8.02, P<0.05), while the percentage of CD206 positive cells was significantly higher than that in blank control group (t=7.21, P<0.05). Conclusions: The hydrogel loaded with mouse adipose-derived stem cells is non-allergenic, can promote the secretion of growth factors in adipose-derived stem cells, promote the polarization of macrophages to M2 phenotype in wound tissue in rats with full-thickness skin defects, and alleviate inflammatory reaction, thereby promoting wound healing.

[Endoscopic ultrasonographic features of submucosal lesions of upper digestive tract suspected gastrointestinal stromal tumors and their correlation with progression and pathological risk grade of the lesions].

Objective: To investigate the endoscopic ultrasonographic (EUS) characteristics of submucosal lesions of upper digestive tract suspected gastrointestinal stromal tumors (GIST) and their correlation with biological behaviors and pathological risk grade of the tumors. Methods: Retrospective cohort study. The EUS findings, follow-up review, surgical treatment and pathological data of patients with suspected GIST at the Gastrointestinal Endoscopy Center of Peking University People's Hospital from January 2013 to April 2021 were collected. All samples were divided into follow-up group and treatment group based on the pathological condition and the patient's treatment intention. According to whether or not the tumor was enlarged in EUS, the follow-up group was divided into non-enlarged group and enlarged group. Paired T-test was used to compare the lesion size before and after follow-up, and logistic regression was used to analyze the risk factors of tumor enlargement. According to the treatment methods, the treatment group was further divided into endoscopic treatment group and surgical treatment group. According to the pathological results and risk grade, the treatment group was further divided into the low-risk group and the medium-risk group. The risk factors of pathological malignant risk were analyzed by logistic regression, and the tumor diameter of patients with moderate or above pathological risk was predicted by receiver operation characteristic (ROC) curve. The relationship between the findings of EUS and the progression and pathological risk of GIST were also explored. Results: Seventy-three cases including 23 males and 50 females, with an age of 58 (30-88) years, were included in the follow-up group, with a mean lesion diameter of (1.21±0.49) cm before follow-up, median follow-up interval of 33.8 months, and a lesion diameter of (1.18±0.49) cm after follow-up. There was no significant difference (all P>0.05) in lesion diameter between before and after follow-up. There was no significant difference (all P>0.05) between tumor enlargement group (18 cases, 24.7%) and non-enlargement group (55 cases, 75.3%). One hundred and thirty-eight cases, including 52 males and 86 females, with an age of 60 (19-84) years, were enrolled in the treatment group, with a mean EUS estimated diameter of (2.55±1.35) cm and pathological diameters of (3.43±2.42) cm. Ninety-five (68.8%) of these cases were pathologically confirmed as GIST while 43 cases were diagnosed as other tumor types, including 37 benign tumors and 6 malignant tumors. In multifactorial logistic regression analysis, only the increase of tumor diameter [OR (95%CI): 1.800 (1.172-2.766), P=0.007] was a risk factor for pathological intermediate or higher risk. The optimal tumor diameter for predicting pathological intermediate or higher risk using ROC curve analysis was 2.75 cm, with a sensitivity 71.4%, specificity 79.0%, Youden index 0.5 and area under ROC curve 0.807 (95%CI: 0.703-0.909). Conclusions: EUS is essential for assessing the risk of progression and malignancy of submucosal lesions of upper digestive tract suspected GIST. For lesions of small diameter, the interval of follow-up shall be relatively extended while the indication of treatment could be partially waived.

[Efficacy of two barrier membranes and deproteinized bovine bone mineral on bone regeneration in extraction sockets: A microcomputed tomographic study in dogs].

OBJECTIVE: To evaluate the effect of two barrier membranes [multilaminated small intestinal submucosa (mSIS) and bioresorable collagen membrane (Bio-Gide)] combined with deproteinized bovine bone mineral Bio-Oss on guided bone regeneration through a canine extraction sockets model. METHODS: The distal roots of 18 premolars of the Beagle' s bilateral maxillary and mandibular were removed, and 18 extraction sockets were obtained. They were randomly divided into 3 groups, and the following procedures were performed on the sockets: (1) filled with Bio-Oss and covered by mSIS (mSIS group), (2) filled with Bio-Oss and covered by Bio-Gide (BG group), (3) natural healing (blank control group). Micro-computed tomograph (Micro-CT) was performed 4 and 12 weeks after surgery to eva-luate the new bone regeneration in the sockets of each group. RESULTS: The postoperative healing was uneventful in all the animals, and no complications were observed through the whole study period. Micro-CT analysis showed that the new bone fraction in the mSIS group and the BG group was significantly higher than that in the blank control group at the end of 4 weeks and 12 weeks (P < 0.05), and more new bone fraction was observed in the mSIS group than in the BG group, but the difference was not statistically significant (P>0.05). The new bone fraction of coronal third part of the socket in the mSIS group and BG group at the end of 4 weeks were significantly higher than that of the middle and apical third part of each group (P < 0.05). The values of bone mineral density were similar at 4 weeks in all the groups (P>0.05), but were significantly higher than that in the control group at the end of 12 weeks (P < 0.05). The bone morphometric analysis showed that the trabecular number and trabecular spacing were significantly better in the mSIS group and the BG group than in the control group at the end of 4 weeks and 12 weeks (P < 0.05), while the value in the mSIS group was slightly higher than in the BG group, but the difference was not statistically significant (P>0.05). The difference in trabecular thickness between all the groups was not statistically significant (P>0.05). CONCLUSION: mSIS membrane as a barrier membrane combined with deproteinized bovine bone mineral can enhance new bone formation in canine extraction sockets, similar to Bio-Gide collagen membrane.

MiR-506-3p acts as a novel tumor suppressor in prostate cancer through targeting GALNT4.

OBJECTIVE: Researches have indicated that microRNA-506-3p (miR-506-3p) was downregulated and functioned as tumor suppressor in cancers. However, the biological role of miR-506-3p in prostate cancer (PCa) remains to be elucidated. MATERIALS AND METHODS: Expression of miR-506-3p in PCa cell lines was measured by qRT-PCR. Effects of miR-506-3p expression on PCa cell behaviors were investigated with MTT assay, colony formation assay, and transwell invasion assay. Connection of miR-506-3p and N-Acetylgalactosaminyltransferase-4 (GALNT4) was analyzed with luciferase activity reporter assay and Western blot assay. RESULTS: miR-506-3p expression was downregulated in PCa cell lines. Function studies demonstrated that overexpression of miR-506-3p inhibits PCa tumor progression in vitro. Mechanistic investigations found GALNT4 was a direct target of miR-506-3p. Overexpression of GALNT4 reversed the tumor-suppressive effects of miR-506-3p on PCa cell. CONCLUSIONS: Our results elucidated genetic silencing of miR-506-3p enhances GALNT4 oncogene expression to accelerate PCa progression.

Factors influencing the choice of practice location among Canadian otolaryngologists.

OBJECTIVES: Little is known about what shapes the choice of employment location in a competitive surgical specialty like otolaryngology - head and neck surgery. This study aimed to identify factors important in determining practice location among Canadian otolaryngologists METHODS: An online survey was distributed nationally to active members of the Canadian Society of Otolaryngology - Head and Neck Surgery. The survey collected data on general demographics, current practice description, training location, factors deemed important in practice location decisions, and job satisfaction. RESULTS: A total of 122 survey responses were collected, with a similar proportion of participants in academic versus community practice. The majority of respondents (73 per cent) practised in the same province as their residency training. Participants identified job vacancy, colleague interaction, spouse opinion and hospital services as important in the decision of practice location. CONCLUSION: Key determinants of practice location among Canadian otolaryngologists include job vacancies, spouse opinion, and colleague interactions. Overall, Canadian otolaryngologists report high satisfaction with current employment.

[Capsule endoscopy for Behcet's disease-treatment: five cases reports].

Behcet's disease (BD) is a chronic vascular inflammatory disease of unknown causes. It is called intestinal BD, when digestive tract is involved. To investigate small bowel feature of intestinal BD, we now report 5 intestinal BD cases undergone capsule endoscopy from December, 2010 to April, 2014 in Peking University People's Hospital. General information, clinical feature and endoscopic feature were presented, and literatures were reviewed. There were 3 male and 2 female patients. Age range was from 23 to 55 years old (median age 40 years old). Disease course was from 3 days to 28 years (median course 9 years). 4 patients were diagnosed as systemic BD, and the rest independent intestinal BD. 4 systemic BD patients all presented as recurrent oral aphthous as initial symptom and had history of vulvar ulcer and skin lesion. They all had gastrointestinal symptoms, including retrosternal pain (2 cases), hematochezia (3 cases), diarrhea (3 cases) and abdominal pain (2 cases). 1 patient had a history of fistula of ileocecal junction and underwent caecectomy. 5 patients all underwent whole digestive tract examination by endoscopy, including gastroscopy, colonoscopy and capsule endoscopy.Except of 1 normal result of colonoscopy, all endoscopy results revealed lesions. Capsule endoscopy results of all patients were abnormal. Types of small intestinal lesion were various, including ulceration, erosion, protrusion and vasculopathy. All digestive tract can be involved in BD patients. Capsule endoscopy can evaluate lesions throughout whole digestive tract, especially in small intestine. As a consequence, it is helpful to explain gastrointestinal symptom, increase early diagnostic rate. Intestinal BD (IBD) mainly involves small bowel, and ileum is the major involved segment, not only limited in ileocecum. The updated perspective of IBD lesion distribution will contribute to differential diagnosis between IBD and Crohn's disease.This is the first time to report capsule endoscopic feature of BD patients in China.

Hyperactivated FRS2α-mediated signaling in prostate cancer cells promotes tumor angiogenesis and predicts poor clinical outcome of patients.

Metastasis of tumors requires angiogenesis, which is comprised of multiple biological processes that are regulated by angiogenic factors. The fibroblast growth factor (FGF) is a potent angiogenic factor and aberrant FGF signaling is a common property of tumors. Yet, how the aberration in cancer cells contributes to angiogenesis in the tumor is not well understood. Most studies of its angiogenic signaling mechanisms have been in endothelial cells. FGF receptor substrate 2α (FRS2α) is an FGF receptor-associated protein required for activation of downstream signaling molecules that include those in the mitogen-activated protein and AKT kinase pathways. Herein, we demonstrated that overactivation and hyperactivity of FRS2α, as well as overexpression of cJUN and HIF1α, were positively correlated with vessel density and progression of human prostate cancer (PCa) toward malignancy. We also demonstrate that FGF upregulated the production of vascular endothelial growth factor A mainly by increasing expression of cJUN and HIF1α. This then promoted recruitment of endothelial cells and vessel formation for the tumor. Tumor angiogenesis in mouse PCa tissues was compromised by tissue-specific ablation of Frs2α in prostate epithelial cells. Depletion of Frs2α expression in human PCa cells and in a preclinical xenograft model, MDA PCa 118b, also significantly suppressed tumor angiogenesis accompanied with decreased tumor growth in the bone. The results underscore the angiogenic role of FRS2α-mediated signaling in tumor epithelial cells in angiogenesis. They provide a rationale for treating PCa with inhibitors of FGF signaling. They also demonstrate the potential of overexpressed FRS2α as a biomarker for PCa diagnosis, prognosis and response to therapies.

Jagged-1-HES-1 signaling inhibits the differentiation of TH17 cells via ROR gammat.

Notch signaling plays an important role in differentiation of T cells. However, little is known as to action of it in differentiation of Th17 cell subset. In this study, a soluble Jagged-1/Fc chimera protein (Jagged-1) was directly used to activate Jagged-1-Notch signaling, while Hes-1-targeting siRNA was used to knock down Hes-1 gene to investigate effect of Jagged-1-Hes-1 signaling on the differentiation of CD4+ T cells into Th17 cells. The results showed that Jagged-1 could promote the expression of Hes-1 and Deltex-1 mRNAs and the expression of NICD, Hes-1 and Deltex-1 proteins, which might be significantly blocked by DAPT, a specific inhibitor of Notch signaling. Jagged-1-Hes-1 signaling resulted in the markedly decreased in situ expression of RORgammat in the CD4+ T cells induced by IL-6 plus TGF-ß. Flow cytometric analysis showed the reduction of IL-17 production in CD4+ T cells by Jagged-1, but the enhancement of it by Hes-1-targeting siRNA. The level of IL-10 produced by the treated cells was also enhanced, whereas the expression of IL-17 was prominently attenuated, which could be offset by anti-Jagged-1 antibody or DAPT. The results indicate that Jagged-1-Hes-1 signaling can suppress the skewing of CD4+ T cells toward Th17 cells via RORgammat, for which Hes-1 may be crucial.

Clinical significance of overexpressed cyclin-dependent kinase subunits 1 and 2 in esophageal carcinoma.

The mammalian cyclin-dependent kinase subunit (Cks) family has two members, Cks1 and Cks2. Overexpression of Cks1 and Cks2 has been reported to be associated with high aggressiveness and poor prognosis in several malignancies, including prostate and hepatocellular carcinomas. However, whether Cks1 and Cks2 are overexpressed in esophageal carcinoma remains uncharacterized. To investigate whether overexpression of the Cks family is clinically relevant in esophageal carcinoma, and whether expression patterns of Cks1 and Cks2 can serve as biomarkers for esophageal carcinoma. Real-time quantitative reverse transcription polymerase chain reaction, immunohistochemistry, and Western blot analyses were applied to detect the expression of Cks1 and Cks2 at the mRNA and protein levels, respectively. The associations between Cks1 or Cks2 expressions and clinical features and p27(kip1) expressions in esophageal carcinoma were analyzed. Comparing with the adjacent noncancerous tissues, esophageal carcinoma exhibited elevated expression of Cks1 in 58% cases at the mRNA level and 54% cases at the protein level, and elevated expression of Cks2 in 65% cases at the mRNA level and 61% cases at the protein level, respectively. The expressions of both Cks1 and Cks2 were negatively associated with the p27(kip1) protein level in the tumor tissues. Furthermore, overexpression of Cks1 and Cks2 in esophageal carcinoma was closely associated with poor pathological features of esophageal carcinoma, including higher histologic grade of tumor, regional lymph nodes invasion, and neoplastic embolus. Overexpression of Cks1 and Cks2 is associated with the aggressive tumor behaviors of esophageal carcinoma. Further efforts are needed to determine whether overexpression of Cks1 and Cks2 can serve as novel biomarkers for esophageal carcinoma.

Eosinophilic enteritis presenting as acute abdomen: US features of two cases.

Eosinophilic enteritis is a rare disease which may mimic acute abdominal emergency. Two sonographically documented cases are presented, which were subsequently proven at operation. Although the sonographic features of severe echolucent bowel wall thickening were not specific, combination with clinical and laboratory data may suggest the correct diagnosis.

Ultrasonography in the diagnosis of acute appendicitis.

Ultrasonography with graded compression was performed in 525 patients with clinical signs of acute appendicitis. Of 207 patients with surgically proven appendicitis the inflamed appendix (diameter greater than or equal to 6 mm) had been visualized sonographically in 177 (86 per cent). The score for non-perforated appendicitis (91 per cent) was higher than for perforated appendicitis (55 per cent). Twenty-four patients in whom an inflamed appendix was seen on ultrasonography did not undergo surgery because of rapidly subsiding symptoms ('abortive appendicitis'). Four of these 24 developed recurrent appendicitis warranting surgery. Two underwent elective appendectomy and 18 have remained symptom-free. Of 155 patients with a subsequently confirmed alternative condition, ultrasonography made the correct diagnosis in 140: bacterial ileocaecitis (69), mesenteric lymphadenitis (eight), gynaecological conditions (34), urological conditions (eight), caecal diverticulitis (six), perforated peptic ulcer (six), Crohn's disease (two) and miscellaneous conditions (seven). Of 139 patients in whom no definite diagnosis was made ultrasonography showed no abnormalities in 138. In four patients a false positive sonographic diagnosis of appendicitis was made and in two patients with appendicitis an alternative condition was incorrectly diagnosed. During the last 3 years of the study the negative appendicectomy rate was 7 per cent and delay beyond 6 h after admission occurred in only 2 per cent of patients with surgically proven appendicitis. When used to complement the clinical diagnosis ultrasonography improves the diagnostic accuracy and patient management in those suspected of having acute appendicitis.