Neural crest-derived mesenchymal stem cells (MSCs) are known to play an essential function during tooth and skeletal development. PRX1⁺ cells constitute an important MSC subtype that is implicated in osteogenesis. However, their potential function in tooth development and regeneration remains elusive. In the present study, we first assessed the cell fate of PRX1⁺ cells during molar development and periodontal ligament (PDL) formation in mice. Furthermore, single-cell RNA sequencing analysis was performed to study the distribution of PRX1⁺ cells in PDL cells. The behavior of PRX1⁺ cells during PDL reconstruction was investigated using an allogeneic transplanted tooth model. Although PRX1⁺ cells are spatial specific and can differentiate into almost all types of mesenchymal cells in first molars, their distribution in third molars is highly limited. The PDL formation is associated with a high number of PRX1⁺ cells; during transplanted teeth PDL reconstruction, PRX1⁺ cells from the recipient alveolar bone participate in angiogenesis as pericytes. Overall, PRX1⁺ cells are a key subtype of dental MSCs involved in the formation of mouse molar and PDL and participate in angiogenesis as pericytes during PDL reconstruction after tooth transplantation.
Animals ; Cell Differentiation ; Mesenchymal Stem Cells ; Mice ; Molar ; Osteogenesis/physiology* ; Periodontal Ligament

Background: /Aim: It is known that an imbalance in the intestinal f lora plays a crucial role in colorectal cancer (CRC), but the effect of food consumption patterns on the types of intestinal flora remains to be clarified. We aimed to analyze the associations between food intake and intestinal flora in healthy and CRC individuals. Methods: Food intake data were recorded using the Food Frequency Questionnaire (FFQ). The composition and diversity of the intestinal flora detected by 16S rRNA gene sequencing, and the data were analyzed by R version 3.1.1 software. Results: Higher intake of red meat or pickled foods, and lower intake of white meat, fruits, vegetables, beans, nuts were found in the CRC group compared with the healthy group. Higher levels of Fusobacteria and Proteobacteria, and lower levels of Firmicutes were observed in the CRC group. Partial correlation analysis revealed that the intake of fruits, beans, and nuts was negatively correlated with Proteobacteria and Fusobacteria, but pickled food was positively correlated with Fusobacteria (p < 0.05). Fish, beans, and nuts intake was negatively correlated with Escherichia (p = 0.01). Multiple regression analysis revealed that vegetable oil (odds ratio [OR], 0.26; 95% confidence interval [CI], 0.13 to 0.82), vegetables (OR, 0.26; 95% CI, 0.10 to 0.64), eggs (OR, 0.26; 95% CI, 0.10 to 0.69), pickled foods (OR, 21.02; 95% CI, 6.02 to 73.45), and red meat (OR, 4.23; 95% CI, 1.68 to 10.60) had an impact on CRC risk. Conclusions The species and abundance of intestinal flora varies between CRC and healthy individuals and may be affected by their food preference.

Objective: To understand knowledge, attitude and behavior toward Coronavirus disease 2019 (COVID 19) among middle school students in Wuhan, in the phase of normalized control and prevention of COVID 19, so as to provide evidence for further health education. Methods: In January 2021, cluster random sampling method was used to select one middle school from Hongshan and Dongxihu District, as well as Donghu high tech zone, respectively. By using the "questionnaire star" platform, questionnaire QR code were sent to students through QQ or wechat by schools. A total of 4 531 middle school students were investigated. Results: Preventive knowledge and behavior rate was 71.5% (3 238) and 56.0% (2 537), respectively. Preventive behaviors towards COVD 19 was reported in 56.0% (2 537) of participants. Students with parents as health care workers reported higher preventive behaviors(P<0.05).Girls had a higher rate of possession of health knowledge for prevention and control than boys. Compared with "essentially no concern about the epidemic","students with less concern about the epidemic" and "those with similar concern as 2020" were more likely to have higher awareness of health knowledge for prevention and control. Compared with the first-year junior middle school students, high school students were less likely to have the rates of knowledge for prevention and control health [OR(95%CI）=1.24（1.09-1.43）,2.56(1.54-4.25),3.30(1.99-5.48),0.49(0.39-0.62),0.45(0.36-0.57),0.63(0.46-0.88)].In terms of health behavior rate, middle school students whose mothers are undergraduates, whose incomes were more than 8 001-15 000 and 15 000 yuan, "whose attention to epidemic situation has declined" , "whose attention is the same as that in 2020" , "who did not plan to study medicine before" , "who are determined to study medicine, and who plan to study medicine more firmly after epidemic situation " were more likely to have health behavior,[OR(95%CI)=1.29(1.04-1.60),1.39（1.07-1.82）,1.74(1.32-2.29),1.77(1.06-2.96),3.47(2.08-5.81)] ,The grade-2 high middle school students had lower probability of preventing and controlling health behaviors [OR(95%CI)=0.74(0.60-0.90)](P<0.05). Preventive knowledge and behaviors towards COVID 19 are mainly from school education, communication with parents and mobile learning. Conclusion Preventive knowledge and behaviors towards COVID 19 among Wuhan middle school students are needed to be improved and targeted health education should be implemented accordingly.

Background: /Aim: It is known that an imbalance in the intestinal f lora plays a crucial role in colorectal cancer (CRC), but the effect of food consumption patterns on the types of intestinal flora remains to be clarified. We aimed to analyze the associations between food intake and intestinal flora in healthy and CRC individuals. Methods: Food intake data were recorded using the Food Frequency Questionnaire (FFQ). The composition and diversity of the intestinal flora detected by 16S rRNA gene sequencing, and the data were analyzed by R version 3.1.1 software. Results: Higher intake of red meat or pickled foods, and lower intake of white meat, fruits, vegetables, beans, nuts were found in the CRC group compared with the healthy group. Higher levels of Fusobacteria and Proteobacteria, and lower levels of Firmicutes were observed in the CRC group. Partial correlation analysis revealed that the intake of fruits, beans, and nuts was negatively correlated with Proteobacteria and Fusobacteria, but pickled food was positively correlated with Fusobacteria (p < 0.05). Fish, beans, and nuts intake was negatively correlated with Escherichia (p = 0.01). Multiple regression analysis revealed that vegetable oil (odds ratio [OR], 0.26; 95% confidence interval [CI], 0.13 to 0.82), vegetables (OR, 0.26; 95% CI, 0.10 to 0.64), eggs (OR, 0.26; 95% CI, 0.10 to 0.69), pickled foods (OR, 21.02; 95% CI, 6.02 to 73.45), and red meat (OR, 4.23; 95% CI, 1.68 to 10.60) had an impact on CRC risk. Conclusions The species and abundance of intestinal flora varies between CRC and healthy individuals and may be affected by their food preference.

Acute respiratory failure due to acute hypoxemia is the major manifestation in severe coronavirus disease 2019 (COVID-19). Rational and effective respiratory support is crucial in the management of COVID-19 patients. High-flow nasal cannula (HFNC) has been utilized widely due to its superiority over other non-invasive respiratory support techniques. To avoid HFNC failure and intubation delay, the key issues are proper patients, timely application and improving compliance. It should be noted that elder patients are vulnerable for failed HFNC. We applied HFNC for oxygen therapy in severe and critical ill COVID-19 patients and summarized the following experiences. Firstly, to select the proper size of nasal catheter, to locate it at suitable place, and to confirm the nose and the upper respiratory airway unobstructed. Secondly, an initial ow of 60 L/min and 37℃ should be given immediately for patients with obvious respiratory distress or weak cough ability; otherwise, low-level support should be given first and the level gradually increased. Thirdly, to avoid hypoxia or hypoxemia, the treatment goal of HFNC should be maintained the oxygen saturation (SpO) above 95% for patients without chronic pulmonary disease. Finally, patients should wear a surgical mask during HFNC treatment to reduce the risk of virus transmission through droplets or aerosols.
Aged ; Betacoronavirus ; isolation & purification ; Cannula ; Coronavirus Infections ; therapy ; Humans ; Oxygen ; administration & dosage ; Pandemics ; Pneumonia, Viral ; therapy

Acute respiratory failure due to acute hypoxemia is the major manifestation in severe coronavirus disease 2019 (COVID-19) induced by severe acute respiratory syndrome coronavirus 2 infection. Rational and effective respiratory support is crucial in the management of COVID-19 patients. High-flow nasal cannula (HFNC) has been utilized widely due to its superiority over other non-invasive respiratory support techniques. To avoid HFNC failure and intubation delay, the key issues are proper patients, timely application and improving compliance. It should be noted that elder patients are vulnerable for failed HFNC. We applied HFNC for oxygen therapy in severe and critical COVID-19 patients and summarized the following experiences. Firstly, to select the proper size of nasal catheter, to locate it at suitable place, and to confirm the nose and the upper respiratory airway unobstructed. Secondly, an initial flow of 60 L/min and 37℃ should be given immediately for patients with obvious respiratory distress or weak cough ability; otherwise, low-level support should be given first and the level gradually increased. Thirdly, to avoid hypoxia or hypoxemia, the treatment goal of HFNC should be maintained the oxygen saturation (SpO) above 95% for patients without chronic pulmonary disease. Finally, patients should wear a surgical mask during HFNC treatment to reduce the risk of virus transmission through droplets or aerosols.
Aged ; Betacoronavirus ; Cannula ; Coronavirus Infections ; complications ; therapy ; Humans ; Hypoxia ; etiology ; prevention & control ; therapy ; Masks ; Oxygen ; administration & dosage ; Oxygen Inhalation Therapy ; instrumentation ; standards ; Pandemics ; Pneumonia, Viral ; complications ; therapy

Objective: To investigate the expression of CD24 in prostate cancer (PC) tissues, and explore its relationship with clinicopathological features of PC patients. Methods:Atotal of 40 cases of PC tissues and 36 cases of corresponding para-cacerous tissues resected during surgery at the Department of Urology Surgery, Quanzhou First HospitalAffiliated to Fujian Medical University from February 2016 to March 2019 were collected for this study; in addition, 46 cases of benign prostatic hyperplasia tissues were collected from patients underwent TURP surgery. Flow cytometry was used to detect the expression of CD24 in above mentioned tissues; One-way analysis of variance was used to analyze the relationship between the expression of CD24 and the age, tumor distribution, preoperative serum PSA, postoperative Gleason score, clinical stage and distant metastasis of PC patients. Results: The positive expression rate and MFI (mean fluorensece intensity) value of CD24 in prostate cancer tissues were significantly higher than those in para-cancerous prostate tissues and benign prostatic hyperplasia tissues (all P<0.05); CD24 positive expression rate and MFI value in PC tissues of patients with preoperative serum PSA≥10 ng/ml, postoperative Gleason score≥8 (low differentiation), clinical stage of T4 and distant metastasis were significantly higher than corresponding control group (all P<0.05); The expression of CD24 gradually increased with the progression of postoperative Gleason score and clinical stage ( P <0.05). Conclusions: The expression of CD24 is increased in prostate cancer tissues. The detection of CD24 expression level can help to determine the occurrence, development, invasion and metastasis of prostate cancer, and has potential clinical application value.

OBJECTIVETo investigate the value of MRI with CUBE sequence in early evaluation of the efficacy of neoadjuvant therapy (NAT) for locally advanced rectal cancer.

METHODSInclusion criteria: (1) rectal cancer proven by biopsy; (2) locally advanced rectal cancer (T3-4 or positive lymph nodes) with distance from lower edge of tumor to anal verge within 12 cm diagnosed by MRI before NAT; (3) acceptance of NAT treatment regulations and completion of NAT; (4) completion of routine MRI scan and CUBE scan before and after 2-course NAT chemotherapy (including new neoadjuvant chemotherapy and chemoradiotherapy); (5) completion of surgery 6-8 weeks after NAT; (6) exclusion of any previous NAT due to rectal malignant tumor or other tumors; (7) exclusion of poor image quality of preoperative routine MRI insufficient for rectal cancer staging or of CUBE image insufficient for tumor volume measurement. Fifty patients with advanced local rectal cancer were recruited in our hospital from February 2014 to January 2016. All the patients underwent MRI before and after 2-course neoadjuvent therapy. Tumor volume on CUBE were measured and the volume changes were calculated: volume difference= pre-treatment volume-post-treatment volume, volume change rate= (pre-treatment volume-post-treatment volume)/ pre-treatment volume. All the patients were categorized into sensitive and non-sensitive group according to postsurgical pathology. Comparisons were made between both groups before and after therapy. ROC curve was used to evaluate the value of CUBE-associated parameters in predicting the efficacy of rectal cancer.

RESULTSAmong enrolled 50 patients with rectal cancer, 31 were male and 19 were female, with mean age of 49.1 years (range 21 to 70 years). T-staging by MRI before NAT was T2N1-2 in 1 case, T3 in 43 cases, T4 in 6 cases. The number of patients after NAT from tumor regression grading (TRG) 0 to TRG3 was 14, 13, 18, 5, respectively. The sensitive group and insensitive group were 45 cases and 5 cases. Mean tumor volume before and after preoperative 2-course NAT was 18.70 (4.14 to 91.77) cmand 9.26 (1.02 to 52.58) cm, respectively, whose difference was significant (U=-5.826, P<0.001). Both measure values of overall tumor volume before and after preoperative NAT between sensitive group and insensitive group did not show significant differences(all P>0.05). While sensitivity group had significantly higher volume difference and change rate compared to insensitive group [ (11.90±10.01) cmvs. (0.65±3.93) cm, P=0.005; 0.45±0.28 vs. 0.09±0.36, P=0.010]. ROC curve revealed that the optimal cutoff value of accurate identification of patients with NAT sensitive was 1.96 cmfor volume difference with sensitivity 86.7% and specificity 80%, and 0.06 for volume change rate with sensitivity 93.3% and specificity 60%.

CONCLUSIONMRI CUBE can predict the efficacy of NAT for early rectal cancer patients accurately and sensitively through the detection of tumor volume change before and after NAT.

OBJECTIVE: To explore the diagnostic value of magnetic resonance imaging(MRI) in anal fistula. METHODS: A total of 2160 patients were clinically diagnosed with anal fistula at the Sixth Affiliated Hospital of Sun Yat-sen University from March 2010 to September 2015. Among them, 232 cases with operative history at other hospital, 218 with Crohn's disease, 6 with rectum cancer and 8 with other disease were excluded, and 1696 patients were finally enrolled and retrospectively analyzed. The saggital FSE T2WI imaging was confirmed based on the midline of body, and then the coronal and axial scanning line were confirmed. The key point was that the coronal scanning line must parallel and the axial scanning line must be perpendicular to the major axis of anal canal. The characteristics of anal fistula were recorded, and anal fistula were classified as five types, including intersphincteric, transphincteric, suprasphincteric, extrasphincteric and superficial fistula according to the Parks classification and our experience. The distribution of internal opening was described by using lithotomy position clock method. RESULTS: Of 1696 patients, 1456 were males and 240 females with median age of 26.5 (0.2 to 87.0) years. Age of 8.4% (143/1696) cases was under 20 years old, of 57.4%(973/1696) cases was between 20 to 40, of 28.4%(482/1696) cases was between 40 to 60, of 5.8%(98/1696) cases was over 60. The 1696 MR examinations included 1128 on 1.5T MR and 568 on 0.5T MR. Of all the anal fistulas was 29.0%(492) high position and 71.0%(1204) was low position. Among the 1696 patients, 1057 were intersphincteric fistulas(62.3%), 407 were transphincteric fistulas(24.0%), 68 were suprasphincteric fistulas(4.0%), 54 were extrasphincteric fistulas (3.2%), 67 were superficial fistulas(4.0%), and 43(2.5%) were difficult to classify. A total of 1996 internal openings were found and most of them were located around the dentate line of 5-7 o'clock in lithotomy position(47.7%, 952/1996). CONCLUSIONS Anal fistula mainly occur in young men, and the most common type is intersphincteric fistula. MRI can accurately classify anal fistulas and clearly demonstrate internal openings, and provide reliable evidence for clinical treatment and surgery.
Adult ; Aged ; Aged, 80 and over ; Anal Canal ; diagnostic imaging ; Female ; Humans ; Magnetic Resonance Imaging ; Male ; Middle Aged ; Rectal Fistula ; classification ; diagnostic imaging ; Retrospective Studies ; Young Adult

OBJECTIVETo demonstrate the clinical applicability of three-dimensional CT angiography by evaluating the anatomic features and variation of inferior mesenteric artery(IMA) and left colic artery(LCA) in order to provide reference to vessel ligation strategy in laparoscopic rectal cancer surgery.

METHODSClinical and image data of 123 patients receiving abdominal multislice CT at The Sixth Affiliated Hospital from 2014 to 2015 were retrospectively analyzed. The images were 3D-reconstructed with computer 3D CT angiography and arterial enhancement phase images were chosen for analysis. Linear distances from IMA root to abdominal aortic bifurcation and from LCA at IMA root level to IMA root were measured. Branch types of IMA, coursing pattern of LCA, and association between LCA and inferior mesenteric vein (IMV) site were summarized.

RESULTSOf 123 cases, 80 were males and 43 were females, mean age was (46.8±16.6) years, body weight was (57.7±10.4) kg, and BMI was (21.3±3.6) kg/m. The average distance from IMA root to abdominal aortic bifurcation was (42.5±7.9) mm, and this distance was closely associated with body weight (OR=4.771, 95%CI: 1.398 to 16.283, P=0.013). Longer distance tended to appear in the heavier patients. LCA and sigmoid artery (SA) originating from same single IMA was found in 61(49.6%) cases; LCA and SA forking at same point in 35(28.5%) cases; LCA and SA coursing together and forking afterwards in 24(19.5%) cases, and LCA disappearing in 3(2.4%) cases. In 71(57.7%) patients, LCA ascended medial to the lateral border of left kidney, while in 16(13.0%) patients, LCA arranged below the inferior border of left kidney. When the LCA site was higher and the distance from LCA to IMA root was closer [distance from LCA to IMA root level was (24.2±9.9) mm, (30.0±15.2) mm and (66.6±12.3) mm, F=83.2, P<0.001]. At the level of IMA root, LCA located medial to IMV in 21(17.1%) cases, located just lateral to IMV in 54(43.9%) cases, and located lateral and ascended far away from IMV in 48(39.0%) cases.

CONCLUSION3D-CT angiography is non-invasive, efficient and accurate in evaluating coursing features and variation of IMA and its branches, which can provide important reference to the surgeons, promising laparoscopic surgery smooth and safe.