Objective:To investigate the cytopathological features of thyroid tumor with DICER1 mutation.Methods:A retrospective study on the preoperative cell smear was conducted on thyroid tumors with DICER1 gene mutations detected by Sanger sequencing in the Department of Pathology Shanghai Sixth People′s Hospital affiliated to Shanghai Jiaotong University School of Medicine from May 2022 to November 2024.Results:Totally 163 cases with histological features indicating DICER1 mutation related thyroid tumor underwent Sanger sequencing. Fifteen cases were confirmed to harbor DICER1 mutation (15/163,9.2%). Fourteen of 15 patients were female, and only 1 was male; average age 42(31,47) years. Eight cases presented with D1709 hotspot mutation (8/15) and 7 cases with the E1813 hotspot mutation (7/15) and there was no statistical significant difference between mutation rate of different hotspot ( F=0.620， P=0.438). All specimens were stained with hematoxylin-eosin staining. A moderate number of cells were observed for all cases, predominantly with macrofollicular pattern and rare small papillae. The cell nuclei were mainly uniform, small, round and dark, slightly enlarged or medium-sized. Several cases could also present RAS-like nuclear features: 3 cases showed visible nuclear grooves. According to the expert consensus on the cytopathological diagnosis of thyroid fine needle aspiration (version 2023),the cytopathological diagnostic categories were: Ⅱ, 6 cases; Ⅲ, 2 cases; Ⅳ, 6 cases; and Ⅴ, 1 case. Postoperative histological diagnoses included follicular thyroid carcinoma in 2 cases, high-grade differentiated thyroid carcinoma in 1 case, follicular thyroid adenoma in 3 cases, follicular thyroid tumor of undetermined malignant potential in 4 case, and thyroid follicular nodular disease in 5 cases. Conclusions:The morphological features of DICER1-mutated thyroid tumors are predominant macrofollicles, with uniformly small round and dark nuclei. It is difficult to identify typically diagnostic atrophic follicles on cell smear, leading to a preoperative diagnosis of benign non-neoplastic or indeterminate category. Therefore, it is necessary to carefully observe the macro-follicles and small round dark nuclear features, which is necessary to suggest a genetic test of DICER1 gene and to confirm the diagnosis before surgery.

This article reports a novel clinical approach for root canal treatment in a case of periapical periodontitis. The patient presented with a buccal wedge-shaped defect exposing the pulp and persistent sinus tract drainage in the mandibular premolar. Radiographic and cone-beam computed tomography (CBCT) evaluation revealed complex root canal anatomy, rendering conventional root canal therapy ineffective for managing the lingual canal. The Department of Stomatology, Peking Union Medical College Hospital (PUMCH) developed an innovative minimally invasive technique—Photoacoustic-steaming United Minimal-invasive Chemomechanical-prepara-tion Hydramatic-obturation(PUMCH) Therapy, which successfully addressed this clinical challenge. This technique employs enhanced chemical disinfection to partially replace mechanical debridement and utilizes negative pressure-guided hydraulic obturation with bioceramic materials. At the 1-month follow-up, complete sinus tract healing and significant symptomatic improvement were observed. This represents the first reported application of PUMCH Therapy in complex root canal anatomy, demonstrating its minimally invasive nature, high efficiency, and precision advantages in endodontic treatment, thereby providing new insights for endodontic therapy.

Objective:To investigate the cytopathological features of thyroid tumor with DICER1 mutation.Methods:A retrospective study on the preoperative cell smear was conducted on thyroid tumors with DICER1 gene mutations detected by Sanger sequencing in the Department of Pathology Shanghai Sixth People′s Hospital affiliated to Shanghai Jiaotong University School of Medicine from May 2022 to November 2024.Results:Totally 163 cases with histological features indicating DICER1 mutation related thyroid tumor underwent Sanger sequencing. Fifteen cases were confirmed to harbor DICER1 mutation (15/163,9.2%). Fourteen of 15 patients were female, and only 1 was male; average age 42(31,47) years. Eight cases presented with D1709 hotspot mutation (8/15) and 7 cases with the E1813 hotspot mutation (7/15) and there was no statistical significant difference between mutation rate of different hotspot ( F=0.620， P=0.438). All specimens were stained with hematoxylin-eosin staining. A moderate number of cells were observed for all cases, predominantly with macrofollicular pattern and rare small papillae. The cell nuclei were mainly uniform, small, round and dark, slightly enlarged or medium-sized. Several cases could also present RAS-like nuclear features: 3 cases showed visible nuclear grooves. According to the expert consensus on the cytopathological diagnosis of thyroid fine needle aspiration (version 2023),the cytopathological diagnostic categories were: Ⅱ, 6 cases; Ⅲ, 2 cases; Ⅳ, 6 cases; and Ⅴ, 1 case. Postoperative histological diagnoses included follicular thyroid carcinoma in 2 cases, high-grade differentiated thyroid carcinoma in 1 case, follicular thyroid adenoma in 3 cases, follicular thyroid tumor of undetermined malignant potential in 4 case, and thyroid follicular nodular disease in 5 cases. Conclusions:The morphological features of DICER1-mutated thyroid tumors are predominant macrofollicles, with uniformly small round and dark nuclei. It is difficult to identify typically diagnostic atrophic follicles on cell smear, leading to a preoperative diagnosis of benign non-neoplastic or indeterminate category. Therefore, it is necessary to carefully observe the macro-follicles and small round dark nuclear features, which is necessary to suggest a genetic test of DICER1 gene and to confirm the diagnosis before surgery.

Objectives:To investigate the effect of concentrated growth factor(CGF)on the repairation of damaged intervertebral disc annulus in rats.Methods:First,4 adult Sprague-Dawley(SD)female rats were se-lected,6-7 weeks old,weight 200-250g,blood was collected from the rats'abdominal veins after anesthesia and processed through centrifugation to isolate CGF.Then 36 adult SD female rats were selected from the same batch rats,and were randomly assigned into three groups of control group,surgery group,and CGF group,with 12 rats per group.In the blank group,only the L4/5 discs were exposed and no other treatment was done.In the control group,only the L4/5 discs were exposed and no other treatment was done.The surgery group had a disc puncture performed at the L4/5 level to induce disc rupture;In the CGF group,after modeling,membrane was made with CGF to cover over the annulus fibrosus defect.Postoperative care included standard antiseptic and analgesic treatments.At 4 and 6 weeks postoperatively,tissues from the L4/5 level were harvested for morphological assessment via hematoxylin and eosin(HE)and type n collagen im-munohistochemistry staining.Results:Postoperatively at both 4 and 6 weeks,with the preservation of the nu-cleus pulposus's integrity,the surgery group demonstrated pronounced annulus fibrosus damage at the L4/5 disc compared to the control group.In contrast,the CGF group showed a significant decrease in annulus fibrosus damage relative to the surgery group.HE staining of disc sections revealed that the CGF group had markedly improved annulus fibrosus healing compared to the surgery group.The immunohistochemistry of typeⅡ collagenase protein of intervertebral disc in each group at 6 weeks after operation indicated that the dam-age of fibrous ring in the surgery group was more serious than that in the other two groups,and the expres-sion of type Ⅱ collagenase protein was concentrated in the damaged site.Compared with the surgery group,the annulus fibrosus damage was lighter in the CGF group,and the expression of type Ⅱ collagenase protein was also concentrated in the damaged site.Conclusions:CGF can effectively promote the repair of damaged intervertebral disc annulus fibrosus.

Objective To summarize the current situation of the implementation of the death case discussion system in county-level medical institutions and analyze the existing problems,to attempt to make suggestions for improvement.Methods Judgmental sampling method was used in this study.A self-made questionnaire was used to conduct field investigation on the im-plementation of the death case discussion system in 16 county-level medical institutions in Chongqing,and semi-structured inter-views were conducted with medical staff.Results All county-level medical institutions have established death case discussion system,but there are many differences in connotative quality.There are many problems in system implementation,such as unclear scope of death case discussion,formality,irregular discussion,poor quality of connotation and lack of systematic supervision.Conclusion As a core medical system,the death case discussion system is an important tool for medical quality management.The medical quality management and medical staff must place a high value on the significance of death case discussion.In order to enhance medical quality and ensure patient safety,we must adhere to the principles of openness and honesty,systematic criti-cism,non-recrimination and non-punishment to conduct death case discussion in time and standardize,keep a record of death case discussions and enhance supervision.

The overall health condition of patients significantly affects the diagnosis,treatment,and prognosis of endodontic diseases.A systemic consideration of the patient's overall health along with oral conditions holds the utmost importance in determining the necessity and feasibility of endodontic therapy,as well as selecting appropriate therapeutic approaches.This expert consensus is a collaborative effort by specialists from endodontics and clinical physicians across the nation based on the current clinical evidence,aiming to provide general guidance on clinical procedures,improve patient safety and enhance clinical outcomes of endodontic therapy in patients with compromised overall health.

Objectives:To investigate the effect of concentrated growth factor(CGF)on the repairation of damaged intervertebral disc annulus in rats.Methods:First,4 adult Sprague-Dawley(SD)female rats were se-lected,6-7 weeks old,weight 200-250g,blood was collected from the rats'abdominal veins after anesthesia and processed through centrifugation to isolate CGF.Then 36 adult SD female rats were selected from the same batch rats,and were randomly assigned into three groups of control group,surgery group,and CGF group,with 12 rats per group.In the blank group,only the L4/5 discs were exposed and no other treatment was done.In the control group,only the L4/5 discs were exposed and no other treatment was done.The surgery group had a disc puncture performed at the L4/5 level to induce disc rupture;In the CGF group,after modeling,membrane was made with CGF to cover over the annulus fibrosus defect.Postoperative care included standard antiseptic and analgesic treatments.At 4 and 6 weeks postoperatively,tissues from the L4/5 level were harvested for morphological assessment via hematoxylin and eosin(HE)and type n collagen im-munohistochemistry staining.Results:Postoperatively at both 4 and 6 weeks,with the preservation of the nu-cleus pulposus's integrity,the surgery group demonstrated pronounced annulus fibrosus damage at the L4/5 disc compared to the control group.In contrast,the CGF group showed a significant decrease in annulus fibrosus damage relative to the surgery group.HE staining of disc sections revealed that the CGF group had markedly improved annulus fibrosus healing compared to the surgery group.The immunohistochemistry of typeⅡ collagenase protein of intervertebral disc in each group at 6 weeks after operation indicated that the dam-age of fibrous ring in the surgery group was more serious than that in the other two groups,and the expres-sion of type Ⅱ collagenase protein was concentrated in the damaged site.Compared with the surgery group,the annulus fibrosus damage was lighter in the CGF group,and the expression of type Ⅱ collagenase protein was also concentrated in the damaged site.Conclusions:CGF can effectively promote the repair of damaged intervertebral disc annulus fibrosus.

Objective:To evaluate the safety and efficacy of a dedicated neonatal-infant brain 0.35 T MRI system.Methods:A dual-center controlled clinical trial was conducted with single-arm objective performance criteria. From June to July 2020, sixty-six infants aged 0-12 (6.3±3.4) months were recruited from Children′s Hospital of Soochow University and the First People′s Hospital of Lianyungang prospectively. All infants underwent brain MRI with a dedicated neonatal-infant 0.35 T brain MRI system, using the dedicated two-channel transceiver head coil. MRI protocol included spin echo T 1WI, fast spin echo T 2WI, fluid attenuated inversion recovery, diffusion weighted imaging and 3D gradient echo sequence. MRI sequences were set with three orientations (axial, sagittal and coronal). Each case received at least two scanning planes and two scanning sequences. Five-point Likert scoring system was used to evaluate the image quality of acquired images, and the target value was set as at least 3 points per image. The temperature, heart rate and breathe of the infants were recorded before and after MRI; the acoustic noise of the MRI system was measured during the scanning process; and the adverse reactions were recorded if presented. Results:Five infants successfully completed their examination during non-sedated sleep in a single attempt, and 61 infants after sedation with chloral hydrate. Based on MRI-based five-point Likert scoring system, 41 cases achieved a score of 5, 21 cases with a score of 4 and 4 cases with a score of 3. Cases with score of 3 was due to movement of the infants during the scan, which resulted in motion related artifacts. The vital signs of all infants showed stable before and after imaging, with heart rate of (126.8±12.9) beats per minute, breathe of (38.2±6.8) times per minute. It was found that 47 cases showed no sign of temperature raise after brain MRI, 15 cases had less than 0.3 ℃ raise and 4 cases had 0.3 ℃ to 0.5 ℃ raise. The noise recorded during the scanning process was (57.5±1.8) dB(A). One case had mild diarrhea on the day of MR scan, and the symptoms disappeared on the second day without treatment; no adverse reactions were found for the rest subjects.Conclusion:Dedicated neonatal-infant 0.35 T brain MRI system allows data acquisition with high safety and excellent image quality, which has potentials in the clinical applications.

Based on practice of video-cases teaching,this paper put forwards four sorts of contradictions,which are the contradiction between time limitation of classroom and expressing limi-tation of video cases,the contradiction between relative independence of video cases (part)and con-sistency of teaching objective (entirety),the contradiction between apparentness of video cases (phe-nomenon)and depth of teaching content (essence)and the contradiction between variability of video case class and control of class by teachers. This paper suggested teaching principle of part conforming to entirety. Meanwhile,it indicated that classroom video case teaching should have strict design, closely coordinated class discussion and teachers should be good at guiding and summarizing. Through these efforts,the above four contradictions can be resolved and designed video case teaching obtained good effect.

Objective To evaluate the dynamic contrast-enhanced MRI (DCE-MRI)in detecting experimentally induced testicular ischemia. Methods Thirty healthy male New Zealand rabbits were randomly assigned into 6 groups. There were 5 rabbits in each of the following experimental groups: ( 1 ) Normal control, (2) Sham-operated, (3) ischemia of 3 h group, (4) ischemia of 6 h group, (5) ischemia of 12 h group, (6) ischemia of 24 h group. In all experiment groups, the right testis served as the internal control while the left testis served as the experimental side. DCE-MRI for each animal lasts about 10 minutes. Signal enhanced ratios (SERs) of ROI for both sides of each group were calculated by a computer, and parameters of SERs of 30 s, 75 s, 120 s and maximal SER were used for statistical analysis.Time intensity curves (TICs) were made for two sides of each group via Excel 2003 software and classified into 4 types. Statistical analysis was performed to compare the differences of SERs between left and right testis by two independent Kolmogorov-Smirnov test. Results In group I and 2, significant enhancement was observed on both testes of 10 rabbits. The enhancement decreased gradually with the elongation of ischemia in torsion groups. Three cases of type Ⅰ and 2 cases of type Ⅱ were observed in group 1,5 cases of type Ⅰ in group two, 2 cases of type Ⅰ and 3 cases of type Ⅱ b in group three, 2 cases of type Ⅰ and 2 cases of type Ⅱ b in group four, 5 cases of type Ⅱ b in group five and 5 cases of type Ⅲ in group six were noticed in the left testes. And in TICs of right testes, all cases showed TICs of type Ⅰ except 2 cases of type Ⅱ a in group six. In four torsion groups, the values for SER75 of the left side were 0. 084%, 0. 076%, 0.164% and 0.065%, while the right side were 0.255%, 0.410%, 0.586% and 0.302% (P ＜0.05). The values for SER120 in group three, five and six were 0.221% , 0.158% and 0.059% for the left side, and 0.405%,0.522% and 0.207% for the right side(P ＜0.05). The values for MSER in group three, five and six were 0.217% ,0.164% and 0.072% for the left side, and 0.405%, 0.586% and 0.302% for the right side(P ＜0.05). Conclusion DCE-MRI technique may be useful in the diagnosis of testicular torsion, which shows potential in the clinical application.