[The clinical characteristics of 497 children with congenital pseudarthrosis of the tibia].

Objective: To investigate the clinical and radiologic characteristics of children with congenital pseudarthrosis of the tibia (CPT) in a single center. Methods: This is a retrospective case series study. According to inclusion and exclusion criteria, clinical data of 497 children with CPT who were treated at Department of Orthopedics, the Children's Hospital Affiliated to Xiangya School of Medicine, Central South University from January 2011 to December 2020 were collected. Baseline data included gender, age at initial visit, age at onset of symptoms, accompanying symptoms, domicile, whether first treated at our hospital, and treatment-related information such as surgical or conservative treatment, surgical complications, etc., were extracted and analyzed using the health information system. Imaging data of the children, including Crawford classification, bilateral leg lengths, presence of fibular pseudarthrosis, and location of pseudarthrosis along the tibia segment, were analyzed using the Picture Archiving and Communication System. Data were compared using independent sample t-test or χ2 tests. Results: Among 497 children with CPT, there were 305 males (61.4 %) and 192 females (38.6%). The age at initial visit was (3.6±3.2) years (range: 0.1 to 16.2 years). Neurofibromatosis type 1 (NF1) symptoms were positive in 340 children (68.4%), and negative in 157 children (31.6 %). Among NF1-positive children, those with symptoms onset before 1 year of age were significantly more than NF1-negative children (74.1%(252/340) vs. 66.2%(104/157);χ2=9.24, P=0.001), and the proportion of fractures (92.9%,316/340) was significantly higher than that in the NF1-negative group (84.7%,133/157) (χ2=8.33, P=0.004). According to imaging data, Crawford type Ⅳ was the most common type, with 321 cases (63.3%), followed by type Ⅱ in 100 cases (19.7%), type Ⅲ in 54 cases (10.7 %) and type Ⅰ in 32 cases (6.3%). Pseudarthrosis occurred in the proximal third of the tibia in 14 cases (2.8 %), in the middle third in 185 cases (36.5 %), and in the distal third in 308 cases (60.8 %). Seventy-four children (14.9 %) had associated fibular pseudarthrosis. The lateral proximal tibial angle was 86.91°±5.21°(range: 72.17° to 102.08°), and the lateral distal tibial angle was 87.27°±10.73°(range: 51.07° to 128.17°). A total of 421 children (84.7%) underwent surgical treatment with (3.1±2.4) surgeries performed per child (range: 0 to 12 surgeries); 76 children (15.3 %) received conservative treatment. Postoperative complications mainly included ankle valgus (77 cases), leg length discrepancy (71 cases), refracture (48 cases), osteomyelitis (11 cases), and hardware failure (10 cases). NF1-positive children underwent more surgeries than NF1-negative children ((5.1±2.2)times vs.(2.1±1.8)times;t=14.93,P<0.01). Conclusions: Crawford type Ⅳ is the most common type of CPT in children. CPT predominantly occurs in the middle or distal third of the tibia. The majority of children with CPT experienced symptoms and were seen at outpatient clinics before the age of 3 years. The main surgical complications currently associated with CPT treatment are ankle valgus and leg length discrepancy. Compared with CPT without NF1, children with NF1-positive CPT tend to have earlier symptom onset and may require more frequent treatments.

[Long term follow-up evaluation of combined surgery for congenital tibial pseudarthrosis in children].

Objective: To explore the long-term effect of combined surgery for the treatment of congenital tibial pseudarthrosis in children. Methods: The clinical data of 44 children with congenital tibial pseudarthrosis who underwent combined surgery (tibial pseudarthrosis tissue resection, intramedullary rod fixation, Ilizarov external fixator fixation, wrapped autologous iliac bone graft) from August 2007 to October 2011 at the Department of Pediatric Orthopedics, Hunan Children's Hospital were collected retrospectively. There were 33 males and 11 females. The age at the time of surgery was (3.7±2.2)years (range:0.6 to 12.4 years), including 25 cases under 3 years old and 19 cases above 3 years old.Among them, 37 cases were complicated with neurofibromatosis type 1.The operation status, postoperative complications and follow-up results were recorded. Results: The follow-up time after surgery was (10.9±0.7)years (range:10 to 11 years).Thirty-nine out of 44 patients (88.6%) achieved initial healing of tibial pseudarthrosis, with an average healing time of (4.3±1.1)months (range:3 to 10months).In the last follow-up, 36 cases (81.8%) had unequal tibial length, 20 cases (45.4%) had refractures, 18 cases (40.9%) had ankle valgus, 9 cases (20.4%) had proximal tibial valgus, and 11 cases (25.0%) had high arched feet.Nine cases (20.4%) developed distal tibial epiphyseal plate bridging.17 cases (38.6%) had abnormal tibial mechanical axis.Seven cases (15.9%) developed needle infection, and one case (2.3%) developed tibial osteomyelitis. 21 patients (47.7%) had excessive growth of the affected femur.Five patients (11.3%) had ankle stiffness, and 34 patients (77.2%) had intramedullary rod displacement that was not in the center of the tibial medullary cavity.Among them, 8 cases (18.1%) protruded the tibial bone cortex and underwent intramedullary rod removal.18 children have reached skeletal maturity, while 26 children have not been followed up until skeletal maturity. Conclusion: Combined surgery for the treatment of congenital pseudarthrosis of the tibia in children has a high initial healing rate, but complications such as unequal tibia length, refracture, and ankle valgus occur during long-term follow-up, requiring multiple surgical treatments.

[Risk factors of intracranial hemorrhage with 125I seeds for the treatment of brain tumors].

Objective: To analyze the risk factors of intracranial hemorrhage after implanting 125-iodine seeds for brain tumors. Methods: A total of 234 patients with intracranial tumors receiving treatment of 125-iodine seeds from March, 2013 to November, 2020 were retrospectively analyzed. Patients were divided into bleeding group and non-bleeding group according to whether postoperative intracranial hemorrhage was reported. Univariate and multivariate analysis was performed by logistic regression to determine the independent risk factors of intracranial hemorrhage. Result: A total of 22 cases (9.4%) reported postoperative intracranial hemorrhage in 234 patients treated with 125-iodine seeds. Univariate analysis showed that the type of tumor and the history of anti-angiogenic drug within one month were possible risk factors (P<0.1). Multivariate logistic regression analysis showed that anti-angiogenic drug within one month was the independent risk factor for intracranial hemorrhage (P<0.05). Conclusions: The application of anti-angiogenic drugs within one month is the independent risk factor of intracranial hemorrhage with 125-iodine seeds for the treatment of brain tumors.

[Identification, molecular structure and expression characteristics of Torso like gene in Anopheles dirus].

OBJECTIVE: To characterize Torso-like (tsl) gene and investigate its expression characteristics in Anopheles dirus, so as to provide a theoretical basis for subsequent functional studies of the tsl gene. METHODS: According to the coding sequences of Drosophila melanogaster and An. gambiae tsl genes, the complete genome of An. dirus was retrieved and the An. dirus tsl gene was characterized. Specific primers were designed and the target gene was amplified using PCR and reverse-transcription PCR assays. The physicochemical properties, signal peptide, transmembrane structure, secondary structure and tertiary structure of the encoded protein TSL were analyzed using bioinformatics tools, and a phylogenetic analysis was performed. In addition, the specific expression of the tls gene was detected in various tissues of An. dirus using a quantitative real-time PCR assay. RESULTS: The An. dirus tsl gene was 16 751 bp in length with a CDS region of 1 134 bp, encoding 377 amino acids, and the encoded TSL protein was a stably hydrophilic protein. The TSL protein was predicted to be a secretory protein that was located in extra-membrane regions containing signal peptides. The secondary structure of the TSL protein contained α-helix (51.72%), extended strand (12.20%), ß-bridge (4.78%) and random coil (31.30%) in the secondary structure, and a 3D homology model was generated using 5cj9.1.A as a template. Phylogenetic analysis revealed a close genetic relationship in the TSL protein between An. dirus and An. farauti. In addition, quantitative real-time PCR assay detected the tsl gene expression in the head, chest, abdomen and foot of An. dirus, with the highest expression in the head and low expression in the foot. CONCLUSIONS: The tsl gene is characterized in An. dirus at a genomic level, and the prediction of the TSL protein structure and the elucidation of the tissue-specific tsl gene expression in An. dirus provide a basis for the further studies on the gene functions.

[Comparison between photodynamic therapy and interventional esophageal stent implantation in dysphagia caused by advanced esophageal cancer].

Objective: To compare the safety and efficacy of photodynamic therapy (PDT) and esophageal stent implantation in improving dysphagia caused by malignant obstruction of middle and advanced esophageal cancer. Methods: A total of 45 patients treated in the Affiliated Hospital of Qingdao University and Qingdao Huangdao District Central Hospital from January 2017 to January 2018 were retrospectively analyzed, of which 34 cases were males and 11 cases were females, 29 cases with the age beyond 60 years old, 41 cases were squamous carcinoma, 4 were adenocarcinoma. PDT was applied to 20 patients and 25 patients received esophageal carotid stenting implantation. There was no significant difference in gender, age, pathological type, location and stage between the two groups. Before treatment, 3 days, 1 month and 3 months after treatment, dysphagia was compared according to Stooler grading criteria, and also the time that patients experienced dysphagia again post treatment. Results: There were no statistical differences between the two groups in dysphagia grade change in 3 days, 1 month and 3 months after treatment (all P>0.05), The stent groups showed advantages towards the PDT group 3 days after treatment in patients with Stooler grading 0 (40%(10/25) vs 0(0/20), P<0.05). No significant differences were found between two groups with Stooler grading 0 (P>0.05) in 1 month and 3 months after treatment. Obstruction symptoms occurred earlier in the stent group compared with the PDT group (P<0.05). Conclusion: Esophageal stent can relieve the symptoms of dysphagia immediately after the implantation, while photodynamic therapy can also prolong the time of esophageal re-obstruction in addition to the immediate effect, with proved safety and efficacy in the treatment of middle and advanced esophageal cancer.

[Effects of remifentanil gradual withdrawal on remifentanil induced postoperative hyperalgesia].

Objective: To explore the effects of remifentanil gradual withdrawal on remifentanil induced postoperative hyperalgesia. Methods: Ninety patients from January to June 2018 undergoing elective laparoscopic hysterectomy under general anaesthesia at Ningbo NO.2 hospital, ASA Ⅰ or Ⅱ grade, aged 20-60, were enrolled in this study and randomly assigned to 3 groups (n=30): Group L (low dose remifentanil), Group H (high dose remifentanil) and Group G (high dose remifentanil with gradual withdrawal). Mechanical pain thresholds (MPT), visual analogue scale (VAS) and additional analgesics were recorded at 6 and 24 hours after the operation. Results: There was no significant difference among the VAS and additional analgesics in three groups at 6 and 24 hours after operation (P>0.05). There was no significant difference among the MPT in three groups before operation (P>0.05). The MPT of group L, group H and group G were (49.8±12.2), (35.5±13.0) and (48.6±11.4) g at 6 hours after surgery, and (51.4±14.3), (36.9±11.1) and (48.8±11.5) g at 24 hours after surgery, respectively, with statistically significant differences (F=12.6, 11.668, both P<0.01). The MPT of group H at 6 h and 24 h after surgery was lower than that of group L (all P<0.01), while the MPT of group G at 6 h and 24 h after surgery was significantly higher than that of group H (all P<0.01). No correlation was observed between MPT and VAS scores or additional analgesics at 6 and 24 hours postoperatively (P>0.05). Conclusion: Remifentanil gradual withdrawal significantly alleviated intraoperative administration of remifentanil induced postoperative hyperalgesia in laparoscopic hysterectomy patients.

[Evaluation of CT-guided iodine-125 seeds brachytherapy for intracranial malignant tumors under control of target and dose].

Objective: To assess the efficacy and safety of CT-guided iodine-125 seeds in the treatment of intracranial malignancies under control of target and dose. Methods: From November 2003 to May 2016, with the clinical data of 412 operations on 310 patients in 12 hospitals in the past 14 years, this study analyzed the method of CT guided iodine-125 particles brachytherapy in the treatment of intracranial malignant tumors and evaluated the efficacy and complications. Stratification analysis of intracranial malignant tumors was performed. Results: Overall survival (OS) of patients with single brain metastases, low-grade glioma, high-grade gliomas, recurrence after surgery, recurrence after radiotherapy and others were 19, 67, 41, 26, 23, 46 months respectively.And the progression free time (PFS) of patients with single brain metastases, low-grade glioma, high-grade gliomas, recurrence after surgery, recurrence after radiotherapy and others were 19, 42, 6, 9, 11, 12 months respectively.Various complications were observed with a relatively low incidence of 10.4%.Three cases deceased at an interval of 7-45 days after treatment. Conclusions: For patients with intracranial malignancies, iodine-125 seeds brachytherapy could achieve a satisfactory treatment efficacy with tolerated complications.Iodine-125 seeds brachytherapy may act as a first-line regimen.

On-chip enrichment and analysis of peptide subsets using a maleimide-functionalized fluorous affinity biochip and nanostructure initiator mass spectrometry.

A new nanostructure initiator mass spectrometry (NIMS) methodology is presented that uses the strategy of fluorous-phase immobilization and capture by a maleimide-functionalized affinity tag to selectively enrich peptide subsets containing cysteine residues. This surface-based approach allows complex protein digests to be analyzed. The proposed platform makes use of a chemically unmodified porous silicon (pSi)-based NIMS chip. Unlike matrix-assisted laser desorption ionization (MALDI) mass spectrometry (MS), the approach described in this paper does not require analytes to be incorporated or cocrystallized with an initiator. The mass spectra generated by the approach in this work are characterized by low background noise and, therefore, high analyte detection sensitivity. Experiments were also conducted that show the potential the approach described in this work has for generating simplified mass spectra for MS/MS analyses.

A fragmentation study of the Rhodamine 610 cation using visible-laser desorption ionization.

The fragmentation of a potential visible matrix-assisted laser desorption ionization: Rhodamine 610 was studied under 532 nm visible irradiation, as a function of anion counter ion. It was found that at a fixed fluence, the chloride salt produced fewer fragments than those formed with ClO(4)(-) or BF(4)(-). Evidence presented suggests that the degree of fragmentation is inversely proportional to the strength of the contact ion pair in the solid state; that is, more energy is deposited into the radical cation which can lead to fragmentation when less energy is required to separate the ion pair. Similar results were found for salts of Rhodamine 6G.

Controlling large-scale film morphology by phase manipulation in interference lithography.

An experimental arrangement is described where a Babinet-Soleil compensator is inserted into the path of one of the three beams used for noncoplanar beam interference lithography. This birefringent element can change the phase of the beam so that either a positive two-dimensional pattern or an inverselike structure is generated in a photoresist without disturbing the mechanical geometry of the setup. Simulations are presented that confirm the validity of this approach. Large defect-free sample areas (>1 cm(2)) with submicrometer periodic patterns were obtained by expanding the laser beams used in the lithography experiment.

Analysis of Xanthate Derivatives by Vacuum Ultraviolet Laser-Time-of-Flight Mass Spectrometry.

A series of liquid O,S-dialkyl dithiocarbonates (xanthate esters) have been synthesized, and time-of-flight (TOF) mass spectra were recorded for their vapors using both ultraviolet (UV) and vacuum ultraviolet (VUV) laser excitation. These compounds are chemical derivatives of low vapor pressure xanthate salts which have found important commercial application as collectors in mineral sulfide flotation circuits. Our experiments demonstrate that esters ionized by short-wavelength VUV light can be detected by parent mass with high efficiency and minimal fragmentation. In contrast, the mass spectra of the same compounds obtained by UV light excitation exhibit a large number of low molecular mass peaks. A preliminary quantitative analysis of the composition of a gas-phase mixture of xanthate esters has also been achieved, which indicates possible subfemtomole detection limits.