A bimodal burst energy distribution of a repeating fast radio burst source.

The event rate, energy distribution and time-domain behaviour of repeating fast radio bursts (FRBs) contain essential information regarding their physical nature and central engine, which are as yet unknown1,2. As the first precisely localized source, FRB 121102 (refs. 3-5) has been extensively observed and shows non-Poisson clustering of bursts over time and a power-law energy distribution6-8. However, the extent of the energy distribution towards the fainter end was not known. Here we report the detection of 1,652 independent bursts with a peak burst rate of 122 h-1, in 59.5 hours spanning 47 days. A peak in the isotropic equivalent energy distribution is found to be approximately 4.8 × 1037 erg at 1.25 GHz, below which the detection of bursts is suppressed. The burst energy distribution is bimodal, and well characterized by a combination of a log-normal function and a generalized Cauchy function. The large number of bursts in hour-long spans allows sensitive periodicity searches between 1 ms and 1,000 s. The non-detection of any periodicity or quasi-periodicity poses challenges for models involving a single rotating compact object. The high burst rate also implies that FRBs must be generated with a high radiative efficiency, disfavouring emission mechanisms with large energy requirements or contrived triggering conditions.

Real-space observation of ultraconfined in-plane anisotropic acoustic terahertz plasmon polaritons.

Thin layers of in-plane anisotropic materials can support ultraconfined polaritons, whose wavelengths depend on the propagation direction. Such polaritons hold potential for the exploration of fundamental material properties and the development of novel nanophotonic devices. However, the real-space observation of ultraconfined in-plane anisotropic plasmon polaritons (PPs)-which exist in much broader spectral ranges than phonon polaritons-has been elusive. Here we apply terahertz nanoscopy to image in-plane anisotropic low-energy PPs in monoclinic Ag2Te platelets. The hybridization of the PPs with their mirror image-by placing the platelets above a Au layer-increases the direction-dependent relative polariton propagation length and the directional polariton confinement. This allows for verifying a linear dispersion and elliptical isofrequency contour in momentum space, revealing in-plane anisotropic acoustic terahertz PPs. Our work shows high-symmetry (elliptical) polaritons on low-symmetry (monoclinic) crystals and demonstrates the use of terahertz PPs for local measurements of anisotropic charge carrier masses and damping.

[Recent progress in the treatment of intractable sialolithiasis].

Sialolithiasis occurs in approximately 0.45% to 1.20% of the general population. The typical clinical symptom manifests as a painful swelling of the affected glands after a meal or upon salivary stimulation, which extremely affects the life quality of the patients. With the development of sialendoscopy and lithotripsy, most sialoliths can be successfully removed with preservation of the gland. However, sialoliths in the deep hilar-parenchymal submandibular ducts and impacted parotid stones located in the proximal ducts continue to pose great challenges. Our research center for salivary gland diseases (in Peking University School and Hospital of Stomatology) has used sialendoscopy for 17 years and treated >2 000 patients with salivary gland calculi. The success rate was approximately 92% for submandibular gland calculi and 95% for parotid calculi. A variety of minimally invasive surgical techniques have been applied and developed, which add substantial improvements in the treatment of refractory sialolithiasis. Further, the radiographic positioning criteria and treatment strategy are proposed for these intractable stones. Most of the hilar-parenchymal submandibular stones are successfully removed by a transoral approach, including transoral duct slitting and intraductal basket grasping, while a small portion of superficial stones can be removed by a mini-incision in submandibular area. Impacted stones located in the distal third of parotid gland ducts are removed via "peri-ostium incision", which is applied to avoid a cicatricial stenosis from a direct ostium incision. Impacted parotid stones located in the middle and proximal third of the Stensen's duct are removed via a direct mini-incision or a peri-auricular flap. A direct transcutaneous mini-incision is commonly performed under local anesthesia with an imperceptible scar, and is indicated for most of impacted stones located in the middle third, hilum and intraglandular ducts. By contrast, a peri-auricular flap is performed under general anesthesia with relatively larger operational injury of the gland parenchyma, and should be best reserved for deeper intraglandular stones. Laser lithotripsy has been applied in the treatment of sialolithiasis in the past decade, and holmium ∶YAG laser is reported to have the best therapeutic effects. During the past 3 years, our research group has performed laser lithotripsy for a few cases with intractable salivary stones. From our experiences, withdrawal of the endoscopic tip 0.5-1.0 cm away from the extremity of the laser fiber, consistent saline irrigation, and careful monitoring of gland swelling are of vital importance for avoidance of injuries of the ductal wall and the vulnerable endoscope lens during lithotripsy. Larger calculi require multiple treatment procedures. The risk of ductal stenosis can be alleviated by endoscopic dilation. In summary, appropriate use of various endoscopy-assisted lithotomy helps preserve the gland function in most of the patients with refractory sialolithiasis. Further studies are needed in the following aspects: Transcervical removal of intraglandular submandibular stones, intraductal laser lithotripsy of impacted parotid stones and deep submandibular stones, evaluation of long-term postoperative function of the affected gland, et al.

[Clinicopathological analysis of 105 patients with fibrous dysplasia of cranio-maxillofacial region].

OBJECTIVE: To compare the clinicopathologic features and prognosis of the different types of fibrous dysplasia (FD) of cranio-maxillofacial region, so as to provide a new reference for clinicians to treat these patients and make prognostic judgement. METHODS: Clinical records, radiographic data and pathological information of 105 patients diagnosed with FD or McCune-Albright syndrome (MAS) at the Department of Oral Pathology, Peking University Hospital of Stomatology from January 2013 to December 2020 were collected. The patients were divided into 4 groups: monostotic FDs, polyostotic FDs, MAS and a specific type called craniofacial fibrous dysplasia (CFD) limited in the craniofacial region. The clinicopathological characteristics, treatment and follow-up data of each type were analyzed. RESULTS: Of all the 105 patients, 46 were males and 59 were females, with a male-to-female ratio of 1 ∶1.3. The onset age ranged from 0 to 56 years and the median age was 12 years. On the basis of different involvement conditions, 4 types were divided. The most common type was monostotic FDs (43 cases, 40.95%), including maxilla (29 cases), mandibular (12 cases) and zygoma (2 cases). 32 cases (30.48%) were diagnosed with polyostotic FDs, 7 cases (6.67%) were MAS, and 23 cases (21.90%) were CFDs confirmed by computed tomography (CT) analysis. CFD was clearly distinct from other types of FD, such as the patient gender and the serum alkaline phosphatase level in peripheral blood before operative surgery. The pathologic findings of various types FD were quite similar, whilst the predominant fibrous tissue hyperplasia could be observed in polyostotic FDs and MAS types. CONCLUSION: The clinicopathologic features of FD in the cranio-maxillofacial region are different from the FD lesions in other parts of the body. The clinicopathological features of CFD are significantly different from those of monostotic and polyostotic FDs in the cranio-maxillofacial region. Therefore, the clinicians should pay attention to distinguish CFD in clinic, imaging and pathology aspects, so as to further clarify its features in clinic management and prognosis.

Computer-aided three-dimensional assessment of periodontal healing distal to the mandibular second molar after coronectomy of the mandibular third molar: a prospective study.

BACKGROUND: The periodontal healing distal to the mandibular second molar (M2M) after coronectomy of the M3M has shown controversial results. We aimed to combine a digital method with cone-beam computed tomography (CBCT) and estimate periodontal healing of M2M after M3M coronectomy. An accurate and stable indicator in three dimensions was also explored tentatively. METHODS: Patients with a M3M in contact with the inferior alveolar canal were included. CBCT was applied immediately after coronectomy (baseline) and 6-months later. Data were investigated with digital software for registration. Previously reported and coronectomy-related factors were included for univariate and multivariate analyses. RESULTS: A total of 181 patients (213 M3Ms) completed 6-month follow-up. Significant reduction in the distal intra-bony defect (DBD) depth of the M2M was shown (1.28 ± 1.24 mm, P < 0.001). DBD depth of the M2M at baseline was the most influential factor (r = 0.59), followed by preoperative M3M condition, age, rotation and migration of the root complex. Remaining enamel (OR = 6.93) and small retromolar space (0.67) contributed to re-contact of the root complex and M2M. Bone volume regenerated in the distal 2 mm was associated significantly with DBD-depth reduction (r = 0.74, P < 0.001). CONCLUSIONS: Bone volume regenerated in the distal 2 mm of the M2M denoted stability of distal periodontal healing of the M2M. DBD depth at baseline was the most influential factor for healing of a DBD of the M2M after M3M coronectomy. The remaining enamel and a small retromolar space could contribute to re-contact of the root complex and the M2M. TRIAL REGISTRATION: China Clinical Trial Center, ChiCTR1800014862 . Registered 10 February 2018.

[Application of computer-assisted design for anterolateral thigh flap in oral and maxillofacial reconstruction].

OBJECTIVE: To investigate the feasibility and accuracy of using digital technology to design anterolateral thigh flap (ALTF) in oral and maxillofacial defect reconstruction. METHODS: Ten cases underwent oral and maxillofacial defects reconstruction with ALTFs in Department of Oral and Maxillofacial Surgery, Peking University School and Hospital of Stomatology from June 2019 to Oct. 2019 were enrolled. There were 7 males and 3 females with the mean age of 47.1 years. Preoperative high frequency color Doppler ultrasound examination was performed to detect the perforators of ALTF. CT data of the thigh was imported in DICOM (digital imaging and communications in medicine) format to the Proplan CMF 3.0 software (Materalise, Belgium), then virtual harvest of ALTF was performed according to the points of perforators detected by high frequency color Doppler ultrasound and the virtual flap volume was calculated by Proplan CMF 3.0 software. ALTF was harvested followed by preoperative virtual design, and the actual flap volume of ALTF was measured by the draining method during the surgery. Finally, the accuracy rate of using high frequency color Doppler ultrasound to detect perforators of ALTFs was calculated, and the differences between the virtual flap volume measured by Propaln CMF 3.0 software and the actual volume of ALTF by the draining method were compared using paired samples T test. RESULTS: Fifteen perforators in the flaps area of 10 patients who underwent oral and maxillofacial defects reconstruction with ALTFs were detected by high frequency color Doppler ultrasound, and 16 perforators were identified during the surgery, with the accuracy rate of 87.5%. The flaps size ranged from 5 cm×7 cm to 8 cm×15 cm, all the 10 flaps survived. The donor sites were primarily closed without skin graft, and no surgery complication was found on the donor site. The mean flap volume measured by Propaln CMF 3.0 software was 71.4 cm³ (range: 36.1-188.4 cm³), and the mean volume measured by the draining method was 70.7 cm³ (range: 38.3-172.5 cm³). There was no significant difference between the virtual flap volume measured by Propaln CMF 3.0 software and the actual volume measured by draining method (t=0.318; P=0.758). CONCLUSION: Preoperative virtual design of ALTF has good feasibility and accuracy and can be used to guide the harvest of ALTF during operation.

[Clinicopathological analysis of 844 cases of odontogenic keratocysts].

OBJECTIVE: To investigate the clinicopathologic features and prognostic factors in odontogenic keratocyst (OKC), and to provide new reference for clinic treatment and management of these patients. METHODS: Clinicopathological data of 844 cases initially diagnosed as or associated with OKC at Department of Oral Pathology, Peking University Hospital of Stomatology from 2000 to 2018 were collected. The cases were divided into 4 groups: sporadic OKCs (intraosseous, cystic lesion irrelevant to nevoid basal cell carcinoma syndrome), syndromic OKCs, solid OKCs and peripheral OKCs. The patients were follow-up for 6 to 216 months and the factors that might relate to recurrence were analyzed. RESULTS: There were 805 cases (95.4%) of sporadic OKCs, 32 cases (3.8%) of syndromic OKCs, 3 cases of solid OKCs and 4 cases of peripheral OKCs. The main age of sporadic OKCs was 36.03 years with the peak at the second and third decades. Ratio of male and female was 1.27:1. The predilection site was the molar and ramus area of mandibular (56.2%). In the study, 428 cases (71.2%) were unilocular in radiography while 28.8% were multilocular. The recurrent rate of enucleation with the follow-up was 20.1% (118/588) while most of them occurred in 1-3 years after surgery. The recurrent rate of multilocular patients (39.0%) was significantly higher than that of the unilocular. Enucleation after marsupialization (43 cases) or enucleation only (545 cases) showed no difference in recurrence (P>0.05). The syndromic OKCs was younger (main 20.97) and preferred to be multiple compared with sporadic OKCs (30/32, 93.7%). The predilection site was also molar and ramus area of mandibular (41.7%). Age and gender distribution of multiple cases had no significant difference with those in sporadic OKCs. More daughter cysts and epithelial islands were seen (56.3% and 17.9%). Furthermore, the recurrent rate was significantly higher than that of the sporadic OKCs (13/29, 44.9%). But there was no evidence of recurrent-related factors. The age of solid and peripheral OKCs, averaged at 45.00 and 65.75 years, were older than others. Four of peripheral OKCs showed no recurrence after enucleation. CONCLUSION: The recurrence rate of sporadic OKCs after enucleation is 20.1%. The multilocular lesions prefer to be recurrent. There is no significant difference of recurrence with enucleation only or enucleation after marsupialization. Compared with sporadic OKCs, the syndromic patients are younger and easier to be multiple. It tends to be recurrent frequently and rapidly. There are no related factors about recurrence of syndromic patients. The clinicians should considerate comprehensively and make an individual management of therapy and follow-up. Solid and peripheral OKCs are rare and older.

[Parotid CT imaging reporting and data system: A preliminary study].

OBJECTIVE: To establish a Parotid Imaging Reporting and Data System (PI-RADS) for CT diagnosis of the parotid gland neoplasms and to investigate the clinical applicable value and feasibility of PI-RADS. METHODS: Patients who had been diagnosed with primary parotid gland neoplasms and had received surgical treatments in Peking University School and Hospital of Stomatology during the period of January 2013 to December 2016 were included in this study. The diagnoses were confirmed by the postoperative pathological examinations in all the patients. The CT imaging data of all patients were retrospectively reviewed and analyzed by two readers in consensus. Imaging characteristics related to the parotid neoplasms were extracted and quantified. Based on comprehensive analysis of the imaging characteristics, the probabilities of the benign and malignant neoplasms were evaluated and classified into six grades, PI-RADS 1-6 (PI-RADS 1: normal parotid gland; PI-RADS 2: confidently benign lesions; PI-RADS 3: probably benign lesions without confirmed evidence of malignancy; PI-RADS 4: suspected malignancy without sufficient evidence of malignancy; PI-RADS 5: confidently malignant lesions; PI-RADS 6: lesions with confirmed pathological evidence of malignancy). RESULTS: A total of 897 patients with 1 003 parotid lesions were included. The lesions included 905 benign and 98 malignant lesions. The proportions of the malignancies in PI-RADS 2, PI-RADS 3, PI-RADS 4 and PI-RADS 5 according to the two readers in consensus were 0.4%, 5.7%, 35.5% and 96.7% respectively. The overall Cohen's Kappa test showed medium consistency between the two independent researchers (κ=0.614, P<0.001, 95%CI: 0.569-0.695). Pearson Chi-square test showed that the proportions of malignancies increased with the diagnostic PI-RADS grades (Cochran-Armitage trend test, Z=-15.579, P<0.001). The results of Pearson Chi-square tests showed significant differences between the grades [PI-RADS 2 and 3 (χ²=12.048, P=0.001); PI-RADS 3 and 4 (χ²=75.231, P<0.001); PI-RADS 4 and 5 (χ²=32.266, P<0.001)]. CONCLUSION: PI-RADS can be used to evaluate the risk of malignancy and will be helpful to improve the imaging diagnosis and clinical treatment of parotid gland neoplasms.

[Magnetic resonance imaging morphological study of the effects of juvenile febrile convulsions on the brain structure of medial temporal lobe epilepsy].

Objective: To investigate the effect of febrile convulsions on gray matter volume (GMV) in medial temporal lobe epilepsy (mTLE) and its correlation with disease duration. Methods: A retrospective study was conducted to collect 41 mTLE patients with a history of febrile convulsions (mTLE-FC), 42 mTLE patients with no initial precipitating injury (mTLE-noIPI), and 42 normal and age and sex matched normal controls. High-resolution T1-weighted (T(1)WI) whole brain MR scans were performed on all subjects. Voxel-based morphometry were used to obtain GMV brain maps, and the GMV differences between the three groups of subjects were compared (P<0.01, GRF corrected). Finally, Spearmen rank correlation analysis was used to explore the correlation between GMV changes and the course of disease. Results: Compared with the normal control subjects, each mTLE group showed extensive GMV reduction, mainly in the affected hippocampus, thalamus, temporal lobe, and bilateral cerebellum. Further analysis found that mTLE-FC group had more significant reductions in GMV than the mTLE-noIPI group in the affected hippocampus, amygdala, inferior temporal gyrus, contralateral hippocampus, para hippocampus, and inner cingulate gyrus. At the same time, the affected amygdala and hippocampal GMV in the mTLE-FC group was significantly negatively related to the course of disease (r=-0.381, P=0.014), while the mTLE-noIPI group had no downward trend (r=0.081, P=0.611). The atrophic trend of the affected amygdala and hippocampus in patients with mTLE-FC was significantly greater than that in patients with mTLE-noIPI (P=0.029, permutation test). Conclusions: There is extensive damage to the gray matter structure of bilateral cerebral hemispheres, mainly in the hippocampus, in mTLE patients. The brain damage of mTLE patients with a history of juvenile fever convulsions is more extensive and serious, and the trend of progressive exacerbation with the course of the disease is more obvious, suggesting mTLE associated with juvenile fever convulsions may have different pathophysiological mechanisms.

Quercetin and Isoquercitrin Inhibiting Hepatic Gluconeogenesis Through LKB1-AMPKα Pathway.

OBJECTIVE: To observe the impact of quercetin and isoquercitrin on gluconeogenesis in hepatocytes. METHODS: Mouse primary hepatocytes were cultured with lactic acid and pyruvic acid. After treatment with quercetin and isoquercitrin for 24 hours, the glucose concentration in the culture supernatant was determined. RT-PCR was used to detect the mRNAs of PEPCK, G6Pase, LKB1, and AMPKα. Protein levels of LKB1, AMPKα, and Thr172 phosphorylation were evaluated by Western blot. RESULTS: The glucose concentration in the gluconeogenesis group (GN) was significantly higher than in the control group (C), but the glucose concentrations in the high level quercetin(group 80Q) and high level isoquercitrin (group 80I) were significantly lower than in the group GN, P<0.01. In the group 80Q, and group 80I, the mRNA levels of PEPCK and LKB1were significantly lower than in the group GN (P<0.01), and the G6Pase mRNA were significantly lower than in the group GN (P<0.05). The protein levels of LKB1 and the phosphorylation of AMPKα Thr172 in the group 80Q, group 40I, and group 80I were higher than in the group GN. The effects of quercetin and isoquercitrin on LKB1 and AMPKα were similar to those of metformin. CONCLUSIONS: Quercetin and isoquercitrin inhibit gluconeogenesis in hepatocytes, which may be related to the LKB1 upregulation and phosphorylation of AMPKα.

[Diagnostic accuracy of cone beam computed tomography with different resolution settings for external root resorption].

OBJECTIVE: To evaluate the diagnostic accuracy of cone beam computed tomography (CBCT) with different resolution settings in detecting the simulated external root resorption defects. METHODS: External root resorption defects were simulated in 51 human single rooted premolar teeth. Cavities simulating root resorption defects of 1 mm in diameter and 0.1 mm, 0.2 mm, and 0.3 mm in depth were drilled in the cervical, middle and apical thirds of lingual surfaces of the teeth. In addition to the 51 locations as controls, a total of 102 cavities were obtained in the present study. Specimens were placed in a human dry mandible and scanned by ProMax 3D and DCT PRO CBCT with different resolution settings, respectively. The three-dimensional CBCT images were evaluated by two experienced observers. The data were analyzed with receiver operating characteristics (ROC) analysis. ROC curves were generated and the area under ROC curve (Az) was employed to express the diagnostic accuracy. RESULTS: The diagnostic accuracy (Az value) of ProMax 3D CBCT with high, normal and low resolution settings were 0.867, 0.703 and 0.665 (P < 0.05), respectively. Defects with depths of 0.2 mm and 0.3 mm were easier to be detected than those with depths of 0.1 mm (P < 0.05). The images obtained by high resolution mode scanning had obvious advantages in detecting smaller defects (depth 0.1 mm and 0.2 mm). The DCT PRO CBCT provided 4 resolution settings including normal quality + normal resolution, normal quality + high resolution, high quality + normal resolution and high quality + high resolution. The Az values for those 4 resolution settings were 0.527, 0.725, 0.743, and 0.794 (P < 0.05), respectively. Similar to ProMax 3D CBCT, the scanning mode with high resolution played a better role in detecting the defects with depth of 0.1 mm. Except for the scanning setting mode with normal quality + normal resolution, the other three modes could well be evaluated for the defects with depth of 0.2 mm and 0.3 mm. CONCLUSION: It is concluded that the diagnostic ability for external root resorption of CBCT could be affected by resolution settings. Computer-aid imaging method can improve the CBCT diagnostic accuracy for external root resorption without increasing the radiation dose level during CBCT scanning.

[Clinicopathological characteristics and diagnosis of IgG4related sialadenitis].

Immunoglobulin G4-related sialadenitis (IgG4-RS) is a newly recognized immune-mediated disease and one of immunoglobulin G4-related diseases (IgG4-RD). Our multidisciplinary research group investigated the clinicopathological characteristics and diagnosis of IgG4-RS during the past 10 years. Clinically, it showed multiple bilateral enlargement of major salivary glands (including sublingual and accessory parotid glands) and lacrimal glands. The comorbid diseases of head and neck region including rhinosinusitis, allergic rhinitis, and lymphadenopathy were commonly seen, which could occur more early than enlargement of major salivary glands. Internal organ involvements, such as autoimmune pancreatitis, sclerosing cholangitis, and interstitial pneumonia could also be seen. Thirty-five (38.5%) patients had the symptom of xerostomia. Saliva flow at rest was lower than normal. Secretory function was reduced more severely in the submandibular glands than in the parotid glands. Serum levels of IgG4 were elevated in almost all the cases and the majority of the patients had increased IgE levels. CT, ultrasonography, and sialography showed their imaging characteristics. Histologically it showed marked lymphoplasmacytic inflammation, large irregular lymphoid follicles with expanded germinal centers, prominent cellular interlobular fibrosis, eosinophil infiltration, and obliterative phlebitis. Their immunohistological examination showed marked IgG-positive and IgG4-positive plasma cell infiltration and high IgG4/IgG ratio. The disease could be divided into three stages according to severity of glandular fibrosis. The serum IgG4 level was higher and the saliva secretion lower as glandular fibrosis increased. IgG4-RS should be differentiated from other diseases with enlargement of major salivary gland and lacrimal gland, such as primary Sjögren syndrome, chronic obstructive submandibular sialadenitis, and eosinophilic hyperplastic lymphogranuloma.

[Endoscopy-assisted sialodochoplasty for the treatment of severe sialoduct stenosis].

OBJECTIVE: To evaluate the effects of endoscopy-assisted sialodochoplasty for the treatment of severe sialoduct stenosis with concurrent megaducts. METHODS: From Jul.2010 to Dec. 2016, 8 patients presenting with severe parotid duct stenosis and 3 patients with occlusion of the Wharton's duct underwent endoscopy-assisted sialodochoplasty.All these patients had concurrent severe ductal ectasiaand manifested a painful swelling of the involved salivary glands.The diameter of ectasia and length of stenosis of the sialoducts were measured preoperatively by sialography, computed tomography, or ultrasonography. The megaducts were opened transorally and sutured to the buccal or oral floor mucosa, therefore creating a neo-ostium. All the patients were followed up periodically after operation. The treatment effects were evaluated by clinical signs, sialogram and sialometry. RESULTS: The length of the Stensen's duct stenosis was 5-12 mm, and the diameter of the concurrent ectasia was 8-16 mm. The length of the Wharton's duct stenosis was 10-20 mm, and the diameter of the concurrent ectasia was 6-8 mm.The neo-ostiums healed uneventfully 2 weeks after operation. The duration of the follow-up varied from 6 to 78 months (median: 24 months). Among the 8 patients with Stensen's duct stenosis, two experienced re-obliteration of the neo-ostium, but the buccal bulge and clinical symptoms disappeared; one reported recurrent clinical symptoms after initial alleviation, which could be controlled with self-massaging; the remaining 5 patients had satisfactory clinical results, i.e., disappearance of the obstruction symptoms and buccal bulge, patent ostium,clean saliva and improvement of the ductal ectasia on sialogram. Three patients with Wharton's duct occlusion were asymptomatic with clear saliva and patent ostium;two exhibited approximately normal appearance and one showed improvement of the sialogram.Sialometry was performed in 9 patients with patent neo-ostium of the involved glands,the resting saliva flow rate of the affected glands showed no differences compared with the normal side, and stimulated flow rate showed a significant increase, though less than the control side.The clinical results included good in 5 patients, fair in 4 patients, and poor in 2 patients, with a total effective rate of 82% (9/11). CONCLUSION: Endoscopy-assisted sialodochoplasty appears to be effective and can be a viable option for patients presenting with severe sialoducts tenosis and concurrent ectasia.

[Dosimetry of cone-beam computed tomography and multi-slice computed tomography scanning for temporal bone].

Objective: To compare the effective radiation dose levels of cone-beam computed tomography (CBCT) with those of multi-slice computed tomography (MSCT) when scanning for the temporal bone. Methods: The absorbed doses of CBCT and MSCT scanners were detected using thermoluminescent dosimeters (TLDs) that were placed in a head and neck phantom and a RGD-3D dose reader.Then the effective doses were calculated and expressed according to the International Commission on Radiation Protection (ICRP) 2007 guidelines. Results: Three-dimensional images about temporal bone can obtained by both CBCT and MSCT scanners in this study.The effective dose value of CBCT scanning for bilateral and unilateral temporal bone was 164.1 µSv (bone marrow: 32.1 µSv; thyroid gland: 10.6 µSv; salivary glands: 31.0 µSv), and 98.1 µSv (bone marrow: 17.4 µSv; thyroid gland: 6.2 µSv; salivary glands: 16.1 µSv), respectively.The dose of MSCT scanning for bilateral temporal bone was 714.6 µSv (bone marrow: 95.1 µSv; thyroid gland: 127.8 µSv; salivary glands: 135.7 µSv). Conclusions: When scanning for the temporal regions, the dose levels for CBCT are lower than those for MSCT.Dose levels reduction for CBCT could be obtained when smaller regions were scanned.

Factors associated with Staphylococcus aureus nasal carriage and molecular characteristics among the general population at a Medical College Campus in Guangzhou, South China.

BACKGROUND: The nasal cavity is the main colonization site of Staphylococcus aureus (S. aureus) in human body. Nasal carriage may be a strong risk factor for some serious infection. There was still limited information about the nasal carriage for S. aureus in south China. METHODS: Sought to determine the prevalence and molecular characteristics of S. aureus nasal carriage, 295 volunteers residing on a medicine campus were investigated and sampled the nasal cavity swab. Selected S. aureus isolates were carried through molecular analysis, including pulsed-field gel electrophoresis (PFGE), multilocus sequence analysis, staphylococcal cassette chromosome mec (SCCmec) and virulence gene detection. RESULTS: A total of 73 S. aureus isolates were recovered from separate subjects (24.7%, 73/295), with one methicillin-resistant S. aureus (MRSA) isolate (0.3%, 1/295). Among the 73 isolates, 71 isolates were successfully grouped into 13 pulsotypes by PFGE analysis, with profiles A and L the most prevalent; 12 sequence types (STs) were found among the 23 isolates which had similar drug resistant spectrum. ST59, ST188 and ST1 were the most prevalent, accounting for 17.4, 13.0 and 13.0% of all isolates, respectively. The MRSA isolate presented ST8-SCCmec III. 56.5% of isolates carried both the staphylococcal enterotoxin A (sea) and enterotoxin B (seb) genes. 83.6% of the S. aureus isolates were resistant to penicillin, all isolates were susceptible to quinupristin/dalfopristin, levofloxacin, teicoplanin and vancomycin. The most common risk factors for S. aureus carriage were being male, age ≤30 years, and nasal cavity cleaning habits. CONCLUSIONS: Colonization by S. aureus was greater among male and young age (20-30 years) students and those with irregularity nasal cleaning. The S. aureus isolates selected were revealed into various sequence types and pulsotypes, indicating molecular heterogeneity among S. aureus isolates from the populations in the medical college in Guangzhou.

[Influence of phosphoglycerate kinase 1 on metastasis and invasion of hepatoma cells and prognosis of liver cancer].

Objective: To investigate the association between expression of phosphoglycerate kinase 1 (PGK1) in liver cancer tissue and prognosis, as well as its influence on metastasis and invasion of hepatocellular carcinoma (HCC) cells. Methods: Overexpression and downregulated expression of PGK1 in HCC cells were mediated by lentivirus to establish hepatoma cell lines with different expression levels of PGK1. The Transwell chamber invasion assay, wound healing assay, and colony-forming assay were used to investigate the influence of PGK1 on metastasis, invasion, and proliferation of HCC cells. Immunohistochemistry was used to measure the expression of PGK1 in liver cancer tissue samples from 116 patients with hepatocellular carcinoma who underwent radical surgery, and the Kaplan-Meier method and the log-rank test were used to determine the association between PGK1 expression and prognosis of patients with liver cancer. Results: HCCLM3 and MHCC97H HCC cells with high metastatic potential had significantly higher expression of PGK1 than Hep3B and Huh7 HCC cells with low metastatic potential. Downregulation of PGK1 expression significantly inhibited the migration (31.2% ± 2.4% vs 12.0% ± 1.3%, t = 21.57, P < 0.01), invasion (58 ± 11 vs 21 ± 8, t = 4.687, P < 0.05), and colony-forming ability (168.6 ± 15.1 vs 118.4 ± 8.1, t = 6.650, P < 0.05) of MHCC97H cells, while overexpression of PGK1 enhanced the migration (62.8% ± 4.4% vs 83.6% ± 6.1%, t = 20.56, P < 0.01), invasion (80 ± 12 vs 121 ± 15, t = 4.603, P < 0.05), and colony-forming ability (52.3 ± 8.6 vs 84.7 ± 9.0, t = 27.18, P < 0.01) of Hep3B cells. The high PGK1 expression group had significantly shorter median disease-free survival time and mean survival time than the low PGK1 expression group (22.00 ± 8.51 vs not reached, P < 0.05; 46.00 ± 16.87 vs not reached, P < 0.01). Conclusions: PGK1 is involved in the regulation of metastasis and invasion of HCC cells and can promote the migration and invasion of HCC cells. Therefore, PGK1 may be an important predictor of prognosis and postoperative recurrence in patients with liver cancer.

Analysis of the drug-resistant characteristics of Klebsiella pneumoniae isolated from the respiratory tract and CTX-M ESBL genes.

The main aim of this study was to understand the relationship between the drug-resistant characteristics of Klebsiella pneumoniae and CTX-M-type extended spectrum ß-lactamases (ESBLs), and to detect the distributions of CTX-M-type ESBLs in clinically isolated strains. CTX-M ESBL genes isolated from the clinical samples were amplified by polymerase chain reaction and identified by sequence analysis; the antibiotic susceptibility of the samples was determined using the Kirby-Bauer disc-diffusion method. One hundred and five strains among the 246 isolated strains of K. pneumoniae tested positive for ESBL production (42.68%); 92 of these produced CTX-M ESBLs. Of the 92 CTX-M ESBL strains, 81 produced CTX-M-1 ESBLs and 11 produced CTX-M-25 ESBLs. Fifty-seven of the CTX-M-1 ESBL- and six of the CTX-M-25 ESBL-producing bacteria had CTX-M ESBL genes that coexisted in the plasmid and chromosome. The Kirby-Bauer antibiotic susceptibility method revealed that CTX-M ESBL-positive strains showed a higher rate of resistance to cefazolin, cefoxitin, cefuroxime, ceftazidime, cefotaxime, aztreonam, levofloxacin, and cotrimoxazole, compared to the CTX-M ESBL-negative strains (P < 0.05). The CTX-M ESBL genes were commonly observed in the K. pneumoniae isolated from respiratory tract samples; these were significantly associated with the drug-resistant characteristics of K. pneumoniae to ß-lactam antibiotics.

Removal of intraglandular calculi in Wharton's duct: clinical outcome and treatment algorithm.

The aim of this study was to propose a treatment strategy for intraglandular submandibular calculi based on calculus site. Seventy-three consecutive patients with impalpable intraglandular submandibular calculi were enrolled retrospectively. The calculi were classified as either post-hilar type, central type, or superficial type. Treatment approaches included transoral duct slitting (TDS), interventional basket retrieval (IBR), intraductal laser lithotripsy (ILL), and transcervical lithotomy (TCL). Complete calculus removal with gland preservation was achieved in 64 patients (87.7%). The success rate for post-hilar, central, and superficial calculi was 86.4% (51/59), 90.9% (10/11), and 100% (3/3), respectively. The treatment approach applied in patients with treatment success was TDS in 32 cases, IBR in 20, ILL in nine, and TCL in three. During follow-up (median 17.3 months), one patient experienced gland atrophy and three had ductal stenosis; the remaining 60 patients (93.8%, 60/64) had good clinical outcomes. In the eight failure cases operated by TDS, the deeply situated calculi could not be detached despite the parenchymal incision in five cases, while the procedure was ceased due to the patient's inability to cooperate in the other three cases. In the remaining failure case, the submandibular gland was sacrificed after calculus extraction via TCL. Application of the proposed treatment algorithm might help preserve gland function in patients with intraglandular submandibular calculi.

[Identification of oxidative stress-related biomarkers in chronic rhinosinusitis with nasal polyps using WGCNA combined with machine learning algorithms].

Objective: To identify diagnostic markers related to oxidative stress in chronic rhinosinusitis with nasal polyps (CRSwNP) by analyzing transcriptome sequencing data, and to investigate their roles in CRSwNP. Methods: Utilizing four CRSwNP sequencing datasets, differentially expressed genes (DEGs) analysis, weighted gene co-expression network analysis (WGCNA), and three machine learning methods for Hub gene selection were performed in this study. Subsequent validation was carried out using external datasets, as well as real-time quantitative polymerase chain reaction (Real-time qPCR), and immunofluorescence staining of clinical samples. Moreover, the diagnostic efficacy of the genes was assessed by receiver operating characteristic (ROC) curve, followed by functional and pathway enrichment analysis, immune-related analysis, and cell population localization. Additionally, a competing endogenous RNA (CeRNA) network was constructed to predict potential drug targets. Statistical analysis and plotting were conducted using SPSS 26.0 and Graphpad Prism9 software. Results: Through data analysis and clinical validation, CP, SERPINF1 and GSTO2 were identified among 4 138 DEGs as oxidative stress markers related to CRSwNP. Specifically, the expression of CP and SERPINF1 increased in CRSwNP, whereas that of GSTO2 decreased, with statistically significant differences (P<0.05). Additionally, an area under the curve (AUC)>0.7 indicated their effectiveness as diagnostic indicators. Importantly, functional analysis indicated that these genes were mainly related to lipid metabolism, cell adhesion migration, and immunity. Single-cell data analysis revealed that SERPINF1 was mainly distributed in epithelial cells, stromal cells, and fibroblasts, while CP was primarily located in epithelial cells, and GSTO2 was minimally present in the epithelial cells and fibroblasts of nasal polyps. Consequently, a CeRNA regulatory network was constructed for the genes CP and GSTO2. This construction allowed for the prediction of potential drugs that could target CP. Conclusion: This study successfully identifies CP, SERPINF1 and GSTO2 as diagnostic and therapeutic markers related to oxidative stress in CRSwNP.