We developed a novel method for the rapid determination of lysozyme using a new fluorogenic substrate that consists of a cationic aluminum phthalocyanine ( tetra ( trimethylammonio ) aluminum phthalocyanine, TTMAAlPc ) , and an anionic mucopolysaccharide ( heparin, HP ) . We found that fluorescence from the cationic aluminum phthalocyanine, a red-region fluorescence probe, was quenched significantly in acidic media in the presence of low concentrations of anionic mucopolysaccharide heparin ( HP) bearing anionic sulfonic acid groups, because of induced aggregation. The practically non-fluorescent substrate degraded into small molecular fragments upon the hydrolysis of lysozyme, and thus the phthalocyanine molecules aggregated in HP were released, resulting in significant fluorescence recovery in the reaction system. This phenomenon forms the foundation of the proposed method. The reaction mechanism was determined using fluorescence spectroscopy and fluorescence anisotropy techniques. Factors that affected the determination were investigated. Under optimal conditions, the linear range was 0. 2-2 mg/L, and the detection limit was 0. 015 mg/L. The developed method is easy to operate and has good selectivity and sensitivity. This method was used in the analysis of practical samples of lysozyme, and the results were in agreement with those determined by a conventional turbidimetric method.

Objective To investigate the effect of gastric bypass on plasma glucose and glucagonlike peptide-1 (GLP-1) during oral glucose tolerance test (OGTT) in non-obese type 2 diabetes mellitus (T2DM) patients suffering from gastric ulcer necessitating a gastrectomy.Methods Thirty-two T2DM patients undergoing gastric bypass (GBP) for gastric ulcer were enrolled in this study.All patients underwent a 3-h OGTT with 75 g glucose (in a total volume of 300 ml) preoperatively and 1 week,1 month,3 months and 6 months after operation.Plasma glucose (PG) and GLP-1 concentrations were measured before (baseline) and then 30,60,120,and 180 minutes after OGTT.Areas under curves (AUC) were calculated by trapezoidal integration.The turnover of the diabetes conditions six months after the surgery were also measured.Results FPG level was (9.5±1.0) mmol/L before surgery,and significantly decreased to (7.4±1.0) mmol/L,one week,(6.5±1.2) mmol/L,one month,(8.0±1.6) mmol/L three months and (5.8±1.0) mmol/L,six months respectively after GBP(P ＜0.01).Peak level and AUC of PG during OGTT significantly decreased at aforementioned four time points after sugery (P ＜ 0.01).Oral glucosestimulated peak levels of GLP-1 was (20±3) pmol/L before GBP,and markedly increased to (83±15)pmol/L,(86±20) pmol/L,(87±22) pmol/L and (92±20) pmol/L respectively after GBP(P＜0.01).Stimulated AUC levels of GLP-1 significantly increased from (2457±395) pmol· min/L to (6499±1227)pmol·min/L,to (7275±1475) pmol·min/L,to (7307±1575) pmol·min/L and to (7974±1594)pmol· min/L during the study respectively(P ＜0.01).BMI levels were similar before and after GBP(P＞0.05).Two patients experienced complications(infection of incision and intractable hiccup).T2DM control rate was 78% when assessed at a time point of six months later.Conclusion Gastric bypass is effective in terms of glucose control and improving gucose tolerance in non-obese T2DM,and the hypoglycemic effect may be contributed to more GLP-1 secretion after GBP,but not to weight loss.

BACKGROUND:We have found that oriented fibers can guide the alignment of smooth muscle cells in our previous experiments. Thus, we designed the experiment to prepare wel aligned polymeric fibers using electrospinning technology, aiming at guiding the growth of esophageal smooth muscle cells to maintain cellmorphology and biological function. OBJECTIVE:Using electrospinning technology, to fabricate isotropic and directed nano-fibrous scaffolds made of polycaprolacton, gelatin and silk fibroin. METHODS:Polycaprolacton/silk fibroin fibers at a ratio of 4:1 were prepared with proper parameters, including solution concentration, voltage and injection speed, under the self-made spinning system. The polycaprolacton/gelatin sheets with mass ratio of 2:1, 1:1 and 1:2, respectively, were also fabricated under suitable process parameters. Using the rol er col ector instead of the metal plate, polycaprolacton/gelatin nano-fibrous scaffold with good alignment of fibers was manufactured. RESULTS AND CONCLUSION:The isotropic polycaprolacton/silk fibroin scaffold with fiber diameter of (535.9±126.7) nm was prepared under conditions of solution concentration (0.08 g/mL), injection speed (1.6 mL/h) and voltage (22.5 kV), and these fibers were uniform with no beads. The isotropic polycaprolacton/gelatin scaffold with fiber diameter of (257.9±117.8) nm was prepared under conditions of solution concentration (0.10 g/mL), injection speed (0.8 mL/h) and voltage (22.5 kV). Using the rol er col ector instead of the previous metal plate, polycaprolacton/gelatin (w:w, 1:2) nano-fibrous scaffold with good alignment of fibers was manufactured. The process parameters were 3 000 r/min of rol ing speed, 0.8 mL/h of injection speed and 15 kV of voltage.

Objective To investigate the clinical characteristics,diagnosis and treatment of congenital tracheobiliary fistula (CTBF) in children.Methods A case of CTBF admitted into the Department of Pediatric Respiration,Hubei Maternal and Child Health Care Hospital in 2016 was reported,and the related literatures were reviewed.The clinical features,diagnostic methods,treatment status and clinical outcomes of the disease were analyzed.Results The patient was 3 years and 7 months old.The main clinical manifestations were recurrent cough,pneumonia and atelectasis.CTBF was diagnosed by means of iodine oil radiography and treated with biological glue plugging under bronchoscopic guidance.So far,only 30 cases of CTBF have been reported in the English literatures,but only 2 cases in the Chinese literatures.The main clinical manifestations were cough,dyspnea,sputum or bile vomiting,aspiration pneumonia,atelectasis or emphysema.Diagnostic methods for CTBF included bronchoscopy,bronchial angiography and cholangiography,hepatobiliary scan,CT scan and magnetic resonance imaging.Except for this case treated with biological glue plugging under bronchoscopic guidance,all other patients were treated with surgery.The operation methods included fistula ligation,gastrostomy,liver resection,fistula jejunum Roux-en-Y anastomosis,hepatic hilum jejunum anastomosis,gallbladder jejunum anastomosis,etc.Only 4 cases died,and the rest of the patients recovered.Conclusions CTBF should be suspected in children with persistent chronic cough.Iodine oil radiography through bronchoscopy is a simple and feasible method for diagnosis of CTBF.Besides surgery,the lavage and the biological glue plugging method through bronchoscopy is also an effective way to treat CTBF in children without severe biliary malformation.

Objective:To explore the potential mechanism of sorafenib resistance associated long non-coding RNA (lncRNA-SRLR) promoted invasion and metastasis in U2OS osteosarcoma cells.Methods:We transfected U2OS cells with negative control lentivirus (LV-NC) or lncRNA-SRLR overexpressed lentivirus (LV-over/SRLR) particles. LV-NC and LV-over/SRLR stable transfected cells (U20S/NC and U20S/SRLR) were selected by primary cell culture medium containing puromycin. The mRNA expressions of lncRNA-SRLR and procollagen-lysine, procollagen-lysine 2-oxoglutarate 5-dioxygenase 2 (PLOD2) were detected by quantitative real-time polymerase chain reaction (qRT-PCR). The effect of lncRNA-SRLR on the invasion of U2OS cells were determined by wound-healing assay and Transwell migration assay. The effect of SRLR on the interleukin-6 (IL-6) secretion of U2OS cells was evaluated by enzyme-linked immunosorbent assay (ELISA) analysis. The subcellular distribution of SRLR in U2OS cells was detected by fluorescence in situ hybridization (FISH) analysis.The expression of PLOD2 in cells was detected by immunofluorescence (IF). The expressions of PLOD2 and focal adhesion kinase (FAK)/signal transducer and activator of transcription 3 (STAT3) signal pathway related proteins in U2OS/NC and U2OS/SRLR cells were detected by western blotting.Results:qRT-PCR assay showed that mRNA expressions of lncRNA-SRLR and PLOD2 in U2OS/SRLR cells were (3 964.97±0.05) and (2.77±0.11), respectively, significantly higher than those in U2OS/NC cells ( P<0.001 or P<0.01). The results of wound-healing and Transwell migration assay showed that over-expression of SRLR markedly promoted the invasion ability of U2OS cells ( P<0.05). The result of ELISA analysis showed that the IL-6 secretions in U2OS/NC or U2OS/SRLR cells were (125.38±11.22) pg/ml or (119.97±13.43) pg/ml, without statistical significance ( P>0.05). The subcellular distribution assay revealed that lncRNA-SRLR is predominately located in the nucleus. The result of IF showed that compared with U2OS/NC cells, the expression of PLOD2 was up-regulated in U2OS/SRLR cells. The result of western blotting showed that over-expression of SRLR significantly increased the expression levels of PLOD2, phosphorylation (p)-FAK and p-STAT3 in U2OS cells ( P<0.01). Conclusion:lncRNA-SRLR promotes invasion and metastasis of osteosarcoma by activating PLOD2-FAK/STAT3 signal axis.

Objective:To explore the potential mechanism of sorafenib resistance associated long non-coding RNA (lncRNA-SRLR) promoted invasion and metastasis in U2OS osteosarcoma cells.Methods:We transfected U2OS cells with negative control lentivirus (LV-NC) or lncRNA-SRLR overexpressed lentivirus (LV-over/SRLR) particles. LV-NC and LV-over/SRLR stable transfected cells (U20S/NC and U20S/SRLR) were selected by primary cell culture medium containing puromycin. The mRNA expressions of lncRNA-SRLR and procollagen-lysine, procollagen-lysine 2-oxoglutarate 5-dioxygenase 2 (PLOD2) were detected by quantitative real-time polymerase chain reaction (qRT-PCR). The effect of lncRNA-SRLR on the invasion of U2OS cells were determined by wound-healing assay and Transwell migration assay. The effect of SRLR on the interleukin-6 (IL-6) secretion of U2OS cells was evaluated by enzyme-linked immunosorbent assay (ELISA) analysis. The subcellular distribution of SRLR in U2OS cells was detected by fluorescence in situ hybridization (FISH) analysis.The expression of PLOD2 in cells was detected by immunofluorescence (IF). The expressions of PLOD2 and focal adhesion kinase (FAK)/signal transducer and activator of transcription 3 (STAT3) signal pathway related proteins in U2OS/NC and U2OS/SRLR cells were detected by western blotting.Results:qRT-PCR assay showed that mRNA expressions of lncRNA-SRLR and PLOD2 in U2OS/SRLR cells were (3 964.97±0.05) and (2.77±0.11), respectively, significantly higher than those in U2OS/NC cells ( P<0.001 or P<0.01). The results of wound-healing and Transwell migration assay showed that over-expression of SRLR markedly promoted the invasion ability of U2OS cells ( P<0.05). The result of ELISA analysis showed that the IL-6 secretions in U2OS/NC or U2OS/SRLR cells were (125.38±11.22) pg/ml or (119.97±13.43) pg/ml, without statistical significance ( P>0.05). The subcellular distribution assay revealed that lncRNA-SRLR is predominately located in the nucleus. The result of IF showed that compared with U2OS/NC cells, the expression of PLOD2 was up-regulated in U2OS/SRLR cells. The result of western blotting showed that over-expression of SRLR significantly increased the expression levels of PLOD2, phosphorylation (p)-FAK and p-STAT3 in U2OS cells ( P<0.01). Conclusion:lncRNA-SRLR promotes invasion and metastasis of osteosarcoma by activating PLOD2-FAK/STAT3 signal axis.

Objective To analyze and summarize the clinical presentation of spontaneous and secondary intracranial hypotension syndrome(IHS).Methods Patients diagnosed with spontaneous or secondary IHS from September 2022 to May 2023 were retrospectively analyzed.The clinical data,imaging features,treatment methods and prognosis were collected.The correlation between intracranial pressure values and clinical characteristics of the patients was statistically analyzed.Results A total of 30 patients were enrolled,and the proportion of spontaneous and secondary IHS was 63%(19 cases)and 37%(11 cases),respectively.In terms of clinical features,orthostatic headache was the most common type(29 cases,96.7%)and most commonly involved occipital region(12 cases,40.0%),followed by frontoparietal region(9 cases,30.0%).Among the brain imaging features,dural enhancement was the most common(17 cases,56.7%).According to CT angiography of spinal cord findings,cerebrospinal fluid leakage is one of the most common location of cervical spine segments(10 cases),and on the thoracic segments(9 cases),followed by the thoracic segments(4 cases)and lumbar segments(4 cases).After conservative treatment and surgical treatment,the total effective rate was 90%.Conclusion Orthostatic headache and cranial MRI"dural enhancement"have strong indication on the definitive diagnosis of IHS.CT myelography is helpful to precisely localize the site of cerebrospinal fluid leakage.Targeted epidural blood patch therapy is an effective method to cure IHS when conservative treatment is ineffective.

Objective To establish a novel clinical application process of the optical surface monitoring system(OSMS)guided volumetric modulated arc therapy(VMAT)for total body irradiation(TBI),and to assess the accuracy and effectiveness of OSMS in inter-fractional auxiliary positioning before radiotherapy and real-time monitoring of intra-fractional motion during radiotherapy.Methods A retrospective analysis was conducted on 15 leukemia patients who underwent OSMS-guided VMAT-TBI before hematopoietic stem cell transplantation.CT simulation positioning was performed,and the whole-body image data which were collected in head-first supine position(HFS)and feet-first supine position(FFS)were transmitted to the treatment planning system for image registration,multicenter VMAT planning and dose verification.The prescription dose was 800 cGy in 4 fractions twice daily.OSMS was used to assist positioning before delivery,and CBCT was used for position verification.During treatment,OSMS was used for monitoring.The intra-fractional error monitored by OSMS in real time was obtained by analyzing the offline log files.Results The mean dose and coverage of the target area in HFS plan were(905.4±19.0)cGy and 93.0%±2.8%.The mean doses to lung and kidney were(603.7±55.7)cGy and(600.4±49.6)cGy,respectively,and the maximum dose to the lens was(393.9±58.9)cGy.The mean dose and coverage of the target area in FFS plan were(888.5±58.9)cGy and 94.0%±3.2%;and the maximum dose at the junction was(1148.9±72.9)cGy.Fractional treatment delivery time was(75.1±15.1)min.OSMS-assisted positioning was carried out before delivery,and the total deviations of CBCT three-dimensional vector in translational and rotation directions were(2.71±1.96)mm and 0.91°±0.90°,respectively.The three-dimensional vector deviation of the intra-fractional motion amplitude in translational direction monitored by OSMS during the treatment was(1.95±1.88)mm,of which the deviation within 1 mm accounted for 57.5%,79.7%and 62.1%in longitudinal,lateral and vertical directions,respectively.The three-dimensional vector deviation in rotation direction was 0.76°±0.72°,of which the deviation within 1°accounted for 93.1%,85.7%and 94.3%in rotation,pitch and roll directions,respectively.Conclusion VMAT simplifies TBI process,while improving target coverage and organs-at-risk sparing.The use of OSMS can reduce positioning errors,especially rotation errors.In order to ensure the accurate implementation of TBI and the safety of patients,it is necessary to use OSMS for auxiliary positioning and intra-fractional position monitoring.

A 6-year-old girl presented with recurrent skin rash at the initial stage, recent joint pain, and neutrophilia was found during a routine blood test. After a multidisciplinary case discussion, she was diagnosed with chronic neutrophil leukemia, and the symptoms were relieved after hydroxyurea and luxolitinib treatment. She received the allogeneic hematopoietic stem cell transplantation subsequently. At present, she is in stable condition and under follow-up. Chronic neutrophil leukemia is a rare disease, which rarely occurs in children. It is more difficult to diagnose in patients with skin rash as the first manifestation. The diagnosis and treatment of this case reflects the important role of multidisciplinary cooperation in the diagnosis and treatment of difficult and rare diseases.