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1.
Org Biomol Chem ; 22(11): 2226-2230, 2024 Mar 13.
Article in English | MEDLINE | ID: mdl-38363281

ABSTRACT

An efficient intermolecular annulation of indazole aldehydes with propargylic amines has been developed for the synthesis of pyrazinoindazoles under catalyst- and additive-free conditions. This straightforward methodology was found to feature a wide substrate scope, high atom economy and environmental advantages. The bioactivity results of these new pyrazino[1,2-b]indazoles showed that some of them exhibited significant antifungal activity.

2.
Small ; 19(44): e2302575, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37394717

ABSTRACT

Osteosarcoma (OS) is the most frequent osseous neoplasm among young people aged 10-20. Currently, the leading treatment for osteosarcoma is a combination of surgery and chemotherapy. However, the mortality remains high due to chemoresistance, metastasis, and recurrence, attributing to the existence of cancer stem cells (CSCs) as reported. To target CSCs, differentiation therapy attracts increasing attention, inducing CSCs to bulk tumor cells with elevated reactive oxygen species (ROS) levels and less chemoresistance. Moreover, increasing studies have implied that ferroptosis is a promising approach to eliminating cancer cells through eliciting oxidative damage and subsequent apoptosis, effectively bypassing chemoresistance. Here, a cancer-cell-membrane-decorated biocompatible formulation (GA-Fe@CMRALi liposome) is constructed to combat OS efficiently by combining distinct differentiation and ferroptosis therapies through magnified ROS-triggered ferroptosis and apoptosis with homologous target capability to tumor sites. The combinational approach exhibited favorable therapeutic efficacy against OS in vitro and in vivo. Impressively, the potential mechanisms are revealed by mRNA sequencing. This study provides a tactical design and typical paradigm of the synergized differentiation and ferroptosis therapies to combat heterogeneous OS.


Subject(s)
Bone Neoplasms , Ferroptosis , Osteosarcoma , Humans , Adolescent , Reactive Oxygen Species , Apoptosis , Osteosarcoma/drug therapy , Bone Neoplasms/drug therapy , Cell Differentiation , Cell Line, Tumor
3.
Nanotechnology ; 34(20)2023 Feb 28.
Article in English | MEDLINE | ID: mdl-36753755

ABSTRACT

Multilayer borophene was predicted to have a similar semiconductor property to its monolayer arise from the weak van der Waals interactions between the layers. Besides, multilayer borophene has a higher carrier mobility than monolayer ones, so it is placed great hopes in applications of photoelectric and photovoltaic devices. However, its preparation and application in experiments of multilayer borophene are still lacking. Here, multilayerα'-4H-borophene was synthesized on semiconductingn-type GaAs substrates using NaBH4source as precursor and hydrogen as the carrier gas under controlled temperature and pressure conditions. The experimental results of the borophene are in good agreement with those of its theoretical prediction. The borophene is a semiconductor with a bandgap of 2.48 eV. To demonstrate the device application potential of the borophene, a near-infrared photodetector composed ofp-type borophene andn-type GaAs was fabricated. The photodetector shows a high photoresponsivity of 0.31 mA·W-1, a high specific detectivity of108Jones, and a fast response or recovery speed of 117 or 109 ms under the irradiation with the wavelength of 940 nm at zero bias. The results prove that theα'-4H-borophene/GaAs photodetector can show high sensitivity and zero consumption, which is of great value in meeting the appeal of sustainable development of society.

4.
Nanotechnology ; 34(31)2023 May 16.
Article in English | MEDLINE | ID: mdl-37116479

ABSTRACT

The growth of artificial synthesis two-dimensional (2D) materials usually demands for suitable substrate due to their rare bulk allotropies. Borophene, as a typical artificial synthetic material, has been proved its substrate-growth on metal or nonmetals and its high theoretical specific capacity (1720 mAh g-1) for next-genatration electrode material, but structural instability and transfer difficulties have hindered the development of its applications. Here, a structurally stable and freestanding AA-stacked-α'-4H-borophene sheets have been synthesized byin situlithium eutectic salt-assisted synthetic method to realize the application of borophene in lithium-ion battery. The atomic structure of AA-α'-4H-borophene with interlayer VdWs was established by comparing the experimental observation with DFT optimal calculation. Different stacking configurations (AA- and AB-) of borophene was realized by a temperature-structure-photoluminescence intensity relationship, and the AA-stacked borophene exhibits higher specific capacity than AB structure. Based on electrochemical performance, the AA-borophene exhibits excellent rate capability and cycling performance due to its non-collapsible stacking configurations, which dominates great initial coulombic efficiency of 87.3% at 200 mA g-1superior to that of black phosphorus-based and borophene/graphene. Meanwhile, it still maintains the coulombic efficiency of 99.13% after 1000 cycles. It also shows a reversible capacity of 181 mAh g-1at 10 mA g-1between the voltage window of 0.01 and 2 V, which improves the reported capacity (43 mAh g-1) of bulk boron anode by over 430%. This work brings fantastic new view of fabricating stable, stacking and freestanding borophene and provides a significative idea on applications of borophene in energy storage domain.

5.
BMC Musculoskelet Disord ; 23(1): 353, 2022 Apr 12.
Article in English | MEDLINE | ID: mdl-35413830

ABSTRACT

BACKGROUND: The study aimed to (1) create a series of pedicle injectors with different number of holes on the sheath especially for the Chinese elderly patients and (2) further investigate the effects of the injectors on the augmentation of pedicle screw among osteoporotic lumbar pedicle channel. METHODS: This study used the biomechanical test module of polyurethane (Pacific Research Laboratory Corp, USA) to simulate the mechanical properties of human osteoporotic cancellous bone. The bone cement injectors were invented based on anatomical parameters of lumbar pedicle in Chinese elderly patients. Mechanical test experiments were performed on the bone cement injectors according to the three groups, namely, a local augmentation group, a full-length augmentation group, and a control group. The local augmentation group included three subgroups including 4-hole group, 6-hole group, and 8-hole group. All holes were laterally placed. The full-length augmentation group was a straight-hole injector. The control group was defined that pedicle screws were inserted without any cement augmentation. Six screws were inserted in each group and the maximum insertion torque was recorded. After 24 h of injecting acrylic bone cement, routine X-ray and CT examinations were performed to evaluate the distribution of bone cement. The axial pull-out force of screws was tested with the help of the material testing system 858 (MTS-858) mechanical tester. RESULTS: The bone cement injectors were consisted of the sheaths and the steel rods and the sheaths had different number of lateral holes. The control group had the lowest maximum insertion torque as compared with the 4-hole, 6-hole, 8-hole, and straight pore groups (P < 0.01), but the differences between the 4-hole, 6-hole, 8-hole, and straight pore groups were no statistical significance. The control group had the lowest maximum axial pull-out force as compared with the other four groups (P < 0.01). Subgroup analysis showed the 8-hole group (161.35 ± 27.17 N) had the lower maximum axial pull-out force as compared with the 4-hole group (217.29 ± 49.68 N), 6-hole group (228.39 ± 57.83 N), and straight pore group (237.55 ± 35.96 N) (P < 0.01). Bone cement was mainly distributed in 1/3 of the distal end of the screw among the 4-hole group, in the middle 1/3 and distal end of the screw among the 6-hole group, in the proximal 1/3 of the screw among the 8-hole group, and along the long axis of the whole screw body in the straight pore group. It might indicate that the 8-hole and straight-hole groups were more vulnerable to spinal canal cement leakage. After pullout, bone cement was also closely connected with the screw without any looseness or fragmentation. CONCLUSIONS: The bone cement injectors with different number of holes can be used to augment the pedicle screw channel. The pedicle screw augmented by the 4-hole or 6-hole sheath may have similar effects to the straight pore injector. However, the 8-hole injector may result in relatively lower pull-out strength and the straight pore injector has the risks of cement leakage as well as cement solidarization near the screw head.


Subject(s)
Pedicle Screws , Aged , Biomechanical Phenomena , Bone Cements/adverse effects , China , Humans , Lumbar Vertebrae/diagnostic imaging , Lumbar Vertebrae/surgery , Polymethyl Methacrylate
6.
Int Orthop ; 46(10): 2329-2337, 2022 10.
Article in English | MEDLINE | ID: mdl-35773531

ABSTRACT

PURPOSE: Transoral approach can accomplish ventral decompression directly. However, surgical site infection (SSI) cannot be ignored. This paper aims to review the prevalence of infection and conduct advice for the treatment of SSI in the cervical spine following the transoral approach. METHODS: A retrospective analysis of patients with SSI after transoral atlantoaxial reduction plate (TARP) surgery was performed. SSI was classified into three kinds according to the modified American CDC criteria. RESULTS: 2.9% (17/581) patients who underwent TARP surgery, experienced SSI, of which five had superficial SSI (SI), eight had deep SSI (DI), and four had organ/space SSI (O/SI). The patients with SI underwent intravenous antibiotic treatment and were ultimately cured. Among the remaining 12 patients with DI and O/SI, 11 underwent reoperation for TARP system removal and subsequently one-stage posterior occipitocervical fixation, and one patient experienced infection two months post-operatively and died without receiving treatment. Among patients who underwent revision surgery, three experienced intracranial infection due to intra-operative dural tears, and continuous lumbar cerebrospinal fluid drainage and intrathecal injection of antibiotics were used as effective and appropriate treatments, with outcomes of one recovery and two deaths. All patients with SSI were begun on intravenous antibiotics with conversion to oral antibiotics. CONCLUSIONS: The incidence of SSI was 2.9% (17/581). Adequate peri-operative preparation, early diagnosis, and appropriate treatment of SSI require further research.


Subject(s)
Cervical Vertebrae , Surgical Wound Infection , Anti-Bacterial Agents/therapeutic use , Cervical Vertebrae/surgery , Humans , Incidence , Retrospective Studies , Surgical Wound Infection/epidemiology , Surgical Wound Infection/etiology
7.
BMC Musculoskelet Disord ; 21(1): 538, 2020 Aug 12.
Article in English | MEDLINE | ID: mdl-32787814

ABSTRACT

BACKGROUND: C1-ring osteosynthesis is a valid alternative to posterior C1-C2 or C0-C2 fusion to preserve important C1-C2 motion in the treatment of unstable atlas fractures. Nevertheless, the fixation instruments used in current studies for transoral anterior C1-ring osteosynthesis were not suitable for anterior anatomy of the atlas or did not have reduction mechanism. We therefore present this report to investigate preliminary clinical effects of transoral anterior C1-ring osteosynthesis using a laminoplasty plate in unstable atlas fractures. METHODS: From January 2014 to December 2017, 13 patients with unstable atlas fractures were retrospectively reviewed. All patients were treated with transoral anterior C1-ring osteosynthesis using a laminoplasty plate. Pre- and postoperative images were obtained to assess reduction of the fracture, internal fixation placement, and bone union. Neurological function, range of motion, and pain levels were evaluated clinically on follow-up. RESULTS: The surgeries were successfully performed in all cases. The average follow-up duration was 16.6 ± 4.4 months (range 12-24 months). One patient suffered screw loosening after operation and underwent replacement operation subsequently. Satisfactory clinical outcomes were achieved in all patients with ideal fracture reduction, reliable plate placement, well-preserved range of motion, and neck pain alleviation. All patients achieved bone union of fractures without loss of reduction or implant failure or C1-C2 instability during the follow-up. No vascular or neurological complication was noted during the operation and follow-up. CONCLUSIONS: Transoral anterior C1-ring osteosynthesis using a laminoplasty plate is a effective surgical treatment for unstable atlas fractures. This technique has a ingenious reduction mechanism, and can provide satisfactory bone union and preservation of C1-C2 motion.


Subject(s)
Cervical Atlas , Laminoplasty , Spinal Fractures , Cervical Atlas/diagnostic imaging , Cervical Atlas/injuries , Cervical Atlas/surgery , Fracture Fixation, Internal , Humans , Retrospective Studies , Spinal Fractures/diagnostic imaging , Spinal Fractures/surgery
8.
Nanotechnology ; 29(12): 125605, 2018 03 23.
Article in English | MEDLINE | ID: mdl-29424370

ABSTRACT

Compared with MoS2 and WS2, selenide analogs have narrower band gaps and higher electron mobilities, which make them more applicable to real electrical devices. In addition, few-layer metal selenides have higher electrical conductivity, carrier mobility and light absorption than the corresponding monolayers. However, the large-scale and high-quality growth of few-layer metal selenides remains a significant challenge. Here, we develop a facile method to grow large-area and highly crystalline few-layer MoSe2 by directly selenizing the Mo foil surface at 550 °C within 60 min under ambient pressure. The atomic layers were controllably grown with thicknesses between 3.4 and 6 nm, which just met the thickness range required for high-performance electrical devices. Furthermore, we fabricated a vertical p-n junction photodetector composed of few-layer MoSe2 and p-type silicon, achieving photoresponsivity higher by two orders of magnitude than that of the reported monolayer counterpart. This technique provides a feasible approach towards preparing other 2D transition metal dichalcogendes for device applications.

9.
Eur Spine J ; 26(3): 825-831, 2017 03.
Article in English | MEDLINE | ID: mdl-25935145

ABSTRACT

PURPOSE: A prospective randomized clinical trial was carried out to observe the analgesic efficacy of ropivacaine for postoperative pain following thoracolumbar spinal surgery. METHODS: Seventy-one patients with elective posterior thoracolumbar spinal surgery were randomly divided into two groups. Local group received 0.33 % ropivacaine by pump through the wound, and intravenous group received flurbiprofen axetil, pentazocine and palonosetron via intravenous pump. We evaluated the level of pain, the incidence of adverse reactions at 2, 4, 6, 12, 24, 36 and 48 h after operation, and the occurrence of chronic pain 3 months later. RESULTS: There were no significant differences in the pain level between the two groups. However, the incidence of nausea, vomiting and chronic pain was significantly lower in the local group. CONCLUSIONS: Our results showed that local infusion of ropivacaine achieved similar analgesic effects to intravenous delivery of analgesic drugs, but significantly reduced incidence of nausea, vomiting and chronic pain.


Subject(s)
Amides , Anesthesia, Local/methods , Anesthetics, Local , Lumbar Vertebrae/surgery , Pain, Postoperative , Thoracic Vertebrae/surgery , Amides/administration & dosage , Amides/adverse effects , Amides/therapeutic use , Anesthetics, Local/administration & dosage , Anesthetics, Local/adverse effects , Anesthetics, Local/therapeutic use , Humans , Orthopedic Procedures/adverse effects , Orthopedic Procedures/statistics & numerical data , Pain Measurement , Pain, Postoperative/drug therapy , Pain, Postoperative/epidemiology , Ropivacaine
10.
J Biol Chem ; 290(22): 14235-44, 2015 May 29.
Article in English | MEDLINE | ID: mdl-25903126

ABSTRACT

EPH kinases are the largest family of receptor tyrosine kinases, and their ligands, ephrins (EFNs), are also cell surface molecules. This work presents evidence that EPHB4 on vascular smooth muscle cells (VSMCs) is involved in blood pressure regulation. We generated gene KO mice with smooth muscle cell-specific deletion of EPHB4. Male KO mice, but not female KO mice, were hypotensive. VSMCs from male KO mice showed reduced contractility when compared with their WT counterparts. Signaling both from EFNBs to EPHB4 (forward signaling) and from EPHB4 to EFNB2 (reverse signaling) modulated VSMC contractility. At the molecular level, the absence of EPHB4 in VSMCs resulted in compromised signaling from Ca(2+)/calmodulin-dependent protein kinase II (CaMKII) to myosin light chain kinase (MLCK) to myosin light chain, the last of which controls the contraction force of motor molecule myosin. Near the cell membrane, an adaptor protein GRIP1, which can associate with EFNB2, was found to be essential in mediating EPHB4-to-EFNB reverse signaling, which regulated VSMC contractility, based on siRNA gene knockdown studies. Our research indicates that EPHB4 plays an essential role in regulating small artery contractility and blood pressure.


Subject(s)
Gene Deletion , Hypotension/metabolism , Muscle, Smooth, Vascular/metabolism , Receptor, EphB4/physiology , Animals , Arteries/metabolism , Blood Pressure , Calcium/metabolism , Female , Genotype , Ligands , Male , Mice , Mice, Inbred C57BL , Mice, Knockout , Muscle Contraction , Phosphorylation , RNA, Small Interfering/metabolism , Sex Factors , Signal Transduction
11.
Am J Physiol Heart Circ Physiol ; 310(7): H861-72, 2016 Apr 01.
Article in English | MEDLINE | ID: mdl-26851246

ABSTRACT

EPH kinases and their ligands, ephrins (EFNs), have vital and diverse biological functions, although their function in blood pressure (BP) control has not been studied in detail. In the present study, we report that Efnb3 gene knockout (KO) led to increased BP in female but not male mice. Vascular smooth muscle cells (VSMCs) were target cells for EFNB3 function in BP regulation. The deletion of EFNB3 augmented contractility of VSMCs from female but not male KO mice, compared with their wild-type (WT) counterparts. Estrogen augmented VSMC contractility while testosterone reduced it in the absence of EFNB3, although these sex hormones had no effect on the contractility of VSMCs from WT mice. The effect of estrogen on KO VSMC contractility was via a nongenomic pathway involving GPER, while that of testosterone was likely via a genomic pathway, according to VSMC contractility assays and GPER knockdown assays. The sex hormone-dependent contraction phenotypes in KO VSMCs were reflected in BP in vivo. Ovariectomy rendered female KO mice normotensive. At the molecular level, EFNB3 KO in VSMCs resulted in reduced myosin light chain kinase phosphorylation, an event enhancing sensitivity to Ca(2+)flux in VSMCs. Our investigation has revealed previously unknown EFNB3 functions in BP regulation and show that EFNB3 might be a hypertension risk gene in certain individuals.


Subject(s)
Blood Pressure , Ephrin-B3/metabolism , Estrogens/metabolism , Muscle Contraction , Muscle, Smooth, Vascular/metabolism , Testosterone/metabolism , Animals , Female , Male , Mice , Mice, Inbred C57BL , Muscle, Smooth, Vascular/physiology , Vasoconstriction
13.
Orthopade ; 45(2): 174-9, 2016 Feb.
Article in English | MEDLINE | ID: mdl-26758728

ABSTRACT

OBJECTIVE: The purpose of this work is to evaluate the outcome of the transoral atlantoaxial pedicle screw technique for the treatment of irreducible atlantoaxial dislocation (IAAD). PATIENTS AND METHODS: A total of 10 patients with IAAD were treated using the transoral atlantoaxial pedicle screw technique. We compared preoperative and postoperative JOA (Japanese Orthopedic Association) scores and observed bone graft fusion rate of the atlantoaxial joint, and examined whether our technique was suitable for the treatment of IAAD. RESULTS: The mean preoperative and postoperative JOA scores (9.2 ± 0.63 and 12.9 ± 0.73, respectively) were significantly different (P < 0.05). The atlantoaxial rigid bony fusion rate was 100 % in 10 cases. All cases were followed up for an average of 5.1 years (range 3.5-6 years). CONCLUSION: The transoral atlantoaxial screw reconstruction plate technique is a novel surgical technique for the treatment of IAAD in upper cervical diseases.


Subject(s)
Atlanto-Axial Joint/injuries , Atlanto-Axial Joint/surgery , Bone Plates , Joint Dislocations/surgery , Pedicle Screws , Spinal Fusion/instrumentation , Adult , Humans , Middle Aged , Prosthesis Design , Spinal Fusion/methods , Treatment Outcome
14.
Arch Orthop Trauma Surg ; 135(3): 313-9, 2015 Mar.
Article in English | MEDLINE | ID: mdl-25567195

ABSTRACT

INTRODUCTION: We evaluate the feasibility, safety, and efficacy of atlantoaxial screw and rod fixation for revision operations in the treatment of re-dislocation after atlantoaxial operations in children. METHODS: Eight consecutive children with atlantoaxial instability required a revision operation due to atlantoaxial re-dislocation caused by the failure of the initial posterior wire fixation. The children were 5-11 years of age with an average age of 8.5 years. The posterior atlantoaxial screw and rod fixation and fusion operation was then performed. Autograft bones harvested from rib (in 3 patients), local bone (2 patients), and the iliac crest bone (3 patients) were used. RESULTS: There were no complications such as vertebral artery or spinal cord injury during the operations or loosening or fracture of the fixations after the operations. Stability and reduction of the atlantoaxial segments were achieved in all patients postoperatively. Follow-up time was 24-55 months, with an average of 35 months. All patients achieved solid osseous fusion demonstrated on plain radiographs or CT scanning. Atlantoaxial screw and rod fixation is feasible in children and may be considered for use during the initial operation in the treatment of atlantoaxial dislocation in children to minimize the need for a revision operation. CONCLUSION: If a revision operation is required, atlantoaxial screw-rod fixation is a safe and effective method. Because the anatomical structure is complicated in revision operation patients, CAD-RP technology could guide the the procedures of exposure and screw placement.


Subject(s)
Atlanto-Axial Joint/surgery , Bone Screws , Joint Dislocations/surgery , Spinal Fusion/instrumentation , Atlanto-Axial Joint/diagnostic imaging , Bone Nails , Bone Transplantation/instrumentation , Bone Wires/adverse effects , Cervical Vertebrae/abnormalities , Cervical Vertebrae/surgery , Child , Child, Preschool , Computer-Aided Design , Feasibility Studies , Female , Humans , Joint Dislocations/diagnostic imaging , Joint Dislocations/etiology , Joint Instability/diagnostic imaging , Joint Instability/etiology , Joint Instability/surgery , Male , Models, Anatomic , Radiography , Recurrence , Reoperation , Retrospective Studies , Surgery, Computer-Assisted , Transplantation, Autologous , Treatment Outcome
15.
Eur Spine J ; 23(8): 1712-9, 2014 Aug.
Article in English | MEDLINE | ID: mdl-24838426

ABSTRACT

PURPOSE: To investigate the (1) radiographic and clinical accuracy of C1 anterior lateral mass screw (C1ALMS) and C2 anterior pedicle screw (C2APS) placement in the transoral atlantoaxial reduction plate (TARP)-III procedure, (2) screw insertion-associated clinical complications and (3) fusion status between C1 and C2. METHODS: Radiographic and clinical data were obtained from the electronic medical record system. Studies were carried out to assess the accuracy of C1ALMS and C2APS placement, the screw insertion-associated clinical complications and the fusion status between C1 and C2. Placement of the screws was assessed using the modified All India Institute of Medical Sciences outcome-based classification. RESULTS: Two-hundred and twelve C1ALMS and 207 C2APS in 106 patients were assessed. The ideal accurate rates were 92.0% (195) and 53.1% (110), and the acceptable accurate rates were 97.6% (207) and 87.0% (180), respectively. One patient died postoperatively due to C2 screw misplacement. There were no symptoms of neurologic and vertebral artery injuries in the rest of the patients. 102 patients (97.1%) achieved solid fusion between C1 and C2. No instrumentation failure due to delayed union or nonunion was observed. CONCLUSION: C1ALMS placement in TARP-III procedures appears to be safe. The cortical breach rate of C2APS is high though clinically the neurovascular complication rate is similar to that of posterior atlantoaxial procedures. Advanced navigation strategies may help improve the accuracy of C2APS placement and decrease potential complications.


Subject(s)
Atlanto-Axial Joint/diagnostic imaging , Atlanto-Axial Joint/surgery , Cervical Vertebrae/diagnostic imaging , Cervical Vertebrae/surgery , Pedicle Screws/standards , Adolescent , Adult , Aged , Bone Plates/standards , Child , Child, Preschool , Female , Follow-Up Studies , Humans , Male , Middle Aged , Postoperative Complications/diagnostic imaging , Postoperative Complications/prevention & control , Radiography , Spinal Fusion/instrumentation , Spinal Fusion/standards , Young Adult
16.
Eur Spine J ; 23(5): 1099-108, 2014 May.
Article in English | MEDLINE | ID: mdl-24442275

ABSTRACT

PURPOSE: To report the surgical techniques and clinical results of one-stage transoral anterior revision surgeries for basilar invagination (BI) with atlantoaxial dislocation (AAD) after posterior decompression. METHODS: From September 2008 to June 2012, 30 patients (16 men and 14 women) who had BI with irreducible atlantoaxial dislocation (IAAD) after posterior decompression underwent anterior revision surgeries in our department. Dynamic cervical radiographs, computed tomographic scans and magnetic resonance imaging were obtained pre- and postoperatively to assess the degree of AAD and ventral compression on the cervical cord. The JOA scoring system was used to evaluate the neurological status. The revision surgeries were conducted by anterior approach, using the transoral atlantoaxial reduction plate (TARP) system. RESULTS: The revision surgeries were successfully performed in all of the cases. The average follow-up duration was 16 months (range 6-39 months). For all of the cases, complete or more than 50 % reduction and decompression of C1-C2 were achieved. The cervicomedullary angle was improved by an average of 32.9°. Bone fusion was achieved within 3-6 months in all of the cases. Clinical symptoms were alleviated in 29 patients (96.7 %) and stabilised in 1 patient (3.3 %). No patients have developed recurrent or progressive atlantoaxial instability so far. CONCLUSION: Anterior revision surgeries using the TARP system achieved reduction, decompression and fixation of C1-C2 in one stage for BI with IAAD. This technique offers an effective, simple and safe method for the revision of such cases after posterior decompression.


Subject(s)
Cervical Atlas/surgery , Internal Fixators , Joint Dislocations/surgery , Adult , Cervical Atlas/diagnostic imaging , Decompression, Surgical , Female , Follow-Up Studies , Humans , Magnetic Resonance Imaging , Male , Middle Aged , Retrospective Studies , Tomography, X-Ray Computed
17.
Eur Spine J ; 23(2): 356-61, 2014 Feb.
Article in English | MEDLINE | ID: mdl-24077897

ABSTRACT

STUDY DESIGN: Human cadaveric study measuring the morphology of C2 vertebra, description of anterior placement of pedicle screw with post-fixation computed tomography (CT) analysis. OBJECTIVE: To assess the potential feasibility and safety anterior placement of C2 pedicle screws. SUMMARY OF BACKGROUND DATA: Posterior pedicle screw fixation has become an established technique for upper cervical reconstruction. To our knowledge few reports in the previous literature have described the placement of or anatomy related to anteriorly approach C2 pedicle screws. METHODS: The morphology of 60 human C2 vertebrae was measured directly to assess the size, position, and relative approach angle of the pedicles from an anterior perspective. In an additional 20 cadaveric cervical spines, bilateral 3.5 mm titanium C2 pedicle screws were placed and analyzed for pedicle morphology and placement accuracy with thin cut, 1 mm axial CT. RESULTS: The mean C2 pedicle width measured directly and by CT scan was 7.8 and 6.6 mm, and the average length of the right and left pedicle was 26.4 and 25 mm, respectively. The mean transverse angle (α) was 17.6° and 21.4°, whereas declination angle (ß) anterior to posterior was 13.8° and 10.6°, respectively. CONCLUSIONS: Quantitative data regarding C2 pedicle shape and location with respect to the anterior placement of pedicle screws have not been previously reported. This study indicates that anterior placement of 3.5 mm C2 pedicle screws through a transoral approach may be both feasible and safe and also provides an important anatomic analysis that may guide clinical application.


Subject(s)
Bone Screws , Cervical Vertebrae/anatomy & histology , Cervical Vertebrae/surgery , Spinal Fusion/methods , Cadaver , Cervical Vertebrae/diagnostic imaging , Feasibility Studies , Humans , Male , Middle Aged , Tomography, X-Ray Computed
18.
Eur Spine J ; 23(8): 1648-55, 2014 Aug.
Article in English | MEDLINE | ID: mdl-24838509

ABSTRACT

PURPOSE: Although direct transoral decompression and one-stage posterior instrumentation can obtain satisfactory cord decompression for the treatment of basilar invagination with atlantoaxial dislocation, surgical injuries run high as combinative anterior-posterior approaches were necessary. Furthermore, the complications will rise notably when involvement of dens and/or clivus in the decompression necessitates relatively complicated surgical techniques. First initiated in 2005, transoral atlantoaxial reduction plate (TARP) works as an internal fixation for the treatment of basilar invagination with irreducible atlantoaxial dislocation. Therefore, this article aimed to describe several operative experiences about this approach, which has delivered successful decompression, fixation and fusion. METHODS: 21 consecutive patients with basilar invagination underwent the TARP operation. The pre- and postoperative medulla-cervical angles were measured and compared. The JOA scores of spinal cord function were calculated pre- and post-operatively. 20 cases (20/21) were followed up to average 12.5 months. RESULTS: Symptoms of all the 20 cases were relieved in different degrees. The postoperative imaging showed the odontoid processes obtained ideal reduction and the internal fixators were all in good position. The medulla-cervical angle was correctd from an average (± standard deviation) 128.7° + 11.9° (n = 20) before surgery to 156.5° + 8.1° (n = 20) after surgery (P < 0.01). The average preoperative and postoperative Japaneses Orthopedic Association scores were 11.25 (n = 20) and 15.9 (n = 20), respectively, indicating 76 % improvement. Screw-loosening was observed in one patient due to severe osteoporosis. After a revised operation with a TARP in another size, the neurological symptoms showed no obvious improvements. Then the treatment was terminated. CONCLUSIONS: The TARP operation and intra-operative traction could reduce the odontoid process superiorly migrating into the foramen magnum, directly ease the ventral compression of spinal cord, and fix the reduced atlantoaxial joints through a single transoral approach without the need of a posterior operation. In this stury, 21 patients were evaluated and 20 did well with TARP operation. The preliminary clinical result was satisfactory.


Subject(s)
Atlanto-Axial Joint/diagnostic imaging , Atlanto-Axial Joint/surgery , Bone Plates , Fracture Fixation, Internal/instrumentation , Platybasia/diagnostic imaging , Platybasia/surgery , Adult , Atlanto-Axial Joint/injuries , Decompression, Surgical/instrumentation , Decompression, Surgical/methods , Female , Fracture Fixation, Internal/methods , Humans , Internal Fixators , Joint Dislocations/surgery , Male , Middle Aged , Orthopedic Procedures/instrumentation , Orthopedic Procedures/methods , Radiography , Spinal Fusion/methods , Young Adult
19.
J Spinal Disord Tech ; 27(4): E143-50, 2014 Jun.
Article in English | MEDLINE | ID: mdl-24866908

ABSTRACT

STUDY DESIGN: This is a retrospective clinical study. OBJECTIVE: To evaluate the clinical efficacy of computer-aided design-rapid prototyping (CAD-RP) techniques in surgical treatments for atlantoaxial instability (AAI). SUMMARY OF BACKGROUND DATA: The complexity of the upper cervical anatomic structures makes the procedures for the treatment of AAI particularly challenging for surgeons. The present study represents a series of C1-C2 surgery for AAI aided by CAD-RP. METHODS: A total of 49 patients (21 men and 28 women) with AAI were treated in our department. According to the use of the CAD-RP technique, the patients were divided into RP group and No RP group. Preoperative CT scans of the upper cervical spine were performed for each patient. For the RP group, physical RP models of the upper cervical spine were manufactured from the 3-dimensional CT data and were used for intraoperative guidance. Personalized surgeries were performed for each case of the 2 groups. The screw malposition rate, frequency of using intraoperative fluoroscopy, operation time, blood loss, and improvement of neurological function were compared between the 2 groups. The mean follow-up duration was 32 months (range, 24-50 mo). RESULTS: The operations were successfully performed in 48 cases expect for 1 case in the No RP group. A total of 204 screws were placed. The intraoperative fluoroscopy frequency and operation time were significantly lower in the RP group than that in the No RP group in both posterior and anterior approaches, whereas the screw malposition rate showed no difference between the 2 groups for both approaches. After the operation, 48 cases achieved satisfactory decompression of the cervical cord and repositioning of the atlantoaxial spine. During follow-up, 47 cases presented improvements in the spinal nerve function within 2 years. CONCLUSIONS: CAD-RP techniques have significant benefits for surgeons providing personalized treatments for AAI, especially cases with complicated deformities.


Subject(s)
Atlanto-Axial Joint/surgery , Cervical Vertebrae/surgery , Computer-Aided Design , Joint Instability/surgery , Adolescent , Adult , Aged , Aged, 80 and over , Atlanto-Axial Joint/diagnostic imaging , Cervical Vertebrae/diagnostic imaging , Child , Child, Preschool , Female , Humans , Joint Instability/diagnostic imaging , Male , Middle Aged , Retrospective Studies , Spinal Fusion/methods , Tomography, X-Ray Computed , Young Adult
20.
Adv Mater ; : e2412210, 2024 Oct 17.
Article in English | MEDLINE | ID: mdl-39420657

ABSTRACT

Reconfigurable devices with field-effect transistor features and neuromorphic behaviors are promising for enhancing data processing capability and reducing power consumption in next-generation semiconductor platforms. However, commonly used 2D materials for reconfigurable devices require additional modulation terminals and suffer from complex and stringent operating rules to obtain specific functionalities. Here, a p-type disordered tellurium oxide is introduced that realizes dual-mode reconfigurability as a logic transistor and a neuromorphic device. Due to the disordered film surface, the enhanced adsorption of oxygen molecules and laser-induced desorption concurrently regulate the carrier concentration in the channel. The device exhibits high-performance p-type characteristics with a field-effect hole mobility of 10.02 cm2 V-1 s-1 and an Ion/Ioff ratio exceeding 106 in the transistor mode. As a neuromorphic device, the vision system exhibits biomimetic bee vision, explicitly responding to the blue-to-ultraviolet light. Finally, in-sensor denoising and invisible image recognition in static and dynamic scenarios are achieved.

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