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The purpose of this study is to explore the effect of using 3D printed pelvic prosthesis to reconstruct bone defect after pelvic tumor resection. From June 2018 to October 2021, a total of 10 patients with pelvic tumors underwent pelvic tumor resection and 3D printed customized hemipelvic prosthesis reconstruction in our hospital. Enneking pelvic surgery subdivision method was used to determine the degree of tumor invasion and the site of prosthesis reconstruction. 2 cases in Zone I, 2 cases in Zone II, 3 cases in Zone I + II, 2 cases in Zone II + III and 1 case in Zone I + II + III. Patients had preoperative VAS scores of 6.5 ± 1.3, postoperative VAS scores of 2.2 ± 0.9, preoperative MSTS-93 scores of 9.4 ± 5.3 and postoperative 19.4 ± 5.9( p < 0.05), all patients had improvement in pain after surgery; Postoperative complications included joint dislocation in 2 cases, myasthenia caused by Guillain-Barre syndrome in 1 case, delayed wound healing in 3 cases and wound infection in 2 cases. Postoperative wound-related complications and dislocations were associated with the extent of the tumor. Patients with tumor invasion of the iliopsoas and gluteus medius muscles had higher complication rates and worse postoperative MSTS scores ( p < 0.05). The patients were followed up for 8 ∼ 28 months. During the follow-up period, 1 case recurred, 4 cases metastasized and 1 case died. All pelvic CTs reviewed 3–6 months after surgery showed good alignment between the 3D printed prosthesis and the bone contact, and tomography showed the growth of trabecular structures into the bone. Overall pain scores decreased and functional scores improved in patients after 3D printed prosthesis replacement for pelvic tumor resection. Long-term bone ingrowth could be seen on the prosthesis-bone contact surface with good stability.

Study design: Retrospective study. Objectives: The traditional PLIF is routinely utilized in severe lumbar spinal stenosis to relief the nerve compression. Nevertheless, the removal of posterior tension-band structure and the denervation and atrophy of the paraspinal muscle affect the clinical efficacy. Therefore, unilateral modified PLIF combined with contralateral fenestration was performed to overcome above-mentioned drawbacks. Methods: 32 modified PLIF and 33 traditional PLIF cases were retrospectively included. Operation time, length of stay (LOS) and blood loss were recorded. VAS of low back pain and leg pain, ODI and Sf-36 score including physical function and body pain were assessed. Fusion rate, lumbar lordosis (LL), intervertebral angle (IVA) and intervertebral height index (IHI) were evaluated radiologically. Results: Modified group possessed less blood loss, shorter operation time and less LOS. Compared with traditional group, the VAS of back pain was lower at 6 months postoperatively ( P < .05) and the ODI score was lower at 3 months postoperatively ( P < .05) in modified group. Modified group exhibited better physical function 3 months postoperatively and lower body pain 6 months postoperatively in Sf-36 score ( P < .05). No statistic difference in LL, IVA, IHI and fusion rate were observed between both groups. Conclusions: Our modified PLIF combining with contralateral fenestration procedure exhibited particular advantages in comparison to traditional PLIF. The preservation of posterior tension-band structure facilitates to less low back pain, low complication rate and early functional recovery.

Purpose: To compare the effects of peripherally inserted central catheters (PICC) and totally implantable venous access devices (port) in terms of complications and shoulder function in patients with malignant bone and soft tissue tumors of the lower limbs. Patients and methods: We analyzed 65 cases of port and 65 cases of PICC at the orthopedic department of the Fourth Hospital of Hebei Medical University. The two groups were compared in terms of catheter indwelling time, catheter-related complications, Constant-Murley shoulder function score, and displacement of the position of the catheter end on the catheterization side. Results: Compared to the PICC group, at six months after catheterization the port group showed better outcomes for catheter indwelling time, catheter-related complications, and Constant-Murley score for the catheterization-side shoulder joint (p < 0.05). The port group also showed less displacement of the catheter end position after 180° abduction of the catheterization-side shoulder joint (p < 0.05). Conclusion: Compared with PICC, port can prolong catheter indwelling time, reduce catheter-related complications, and maintain shoulder joint function, which makes it an ideal venous-access approach when providing chemotherapy to patients with malignant bone and soft tissue tumors of the lower limbs.

The genome guardian p53 functions as a transcription factor that senses numerous cellular stresses and orchestrates the corresponding transcriptional events involved in determining various cellular outcomes, including cell cycle arrest, apoptosis, senescence, DNA repair, and metabolic regulation. In response to diverse stresses, p53 undergoes multiple posttranslational modifications (PTMs) that coordinate with intimate interdependencies to precisely modulate its diverse properties in given biological contexts. Notably, PTMs can recruit ‘reader’ proteins that exclusively recognize specific modifications and facilitate the functional readout of p53. Targeting PTM–reader interplay has been developing into a promising cancer therapeutic strategy. In this review, we summarize the advances in deciphering the ‘PTM codes’ of p53, focusing particularly on the mechanisms by which the specific reader proteins functionally decipher the information harbored within these PTMs of p53. We also highlight the potential applications of intervention with p53 PTM–reader interactions in cancer therapy and discuss perspectives on the ‘PTMomic’ study of p53 and other proteins.

Due to the dielectric film with charges from corona discharge of high-voltage direct current (HVDC) overhead lines, the electric field near the greenhouses covered by the dielectric film can be distorted. The electric field at some position on the ground level can be measured under the dielectric film. However, the distribution characteristics of the electric field cannot be obtained. In this article, based on the measurement results of some defined points, an algorithm to calculate the ion flow field with the presence of a dielectric film is proposed. Poisson’s equation and the current continuity equation are iteratively solved by the finite-element method (FEM) and the divergence theorem, respectively. The experiment validates the validity of the hybrid method. The research is helpful to understand the influence of charged dielectric film fully.

The oncoprotein SET is frequently overexpressed in many types of tumors and contributes to malignant initiation and progression through multiple mechanisms, including the hijacking of the tumor suppressors p53 and PP2A. Targeting aberrant SET represents a promising strategy for cancer intervention. However, the mechanism by which endogenous SET is regulated in cancer cells remains largely unknown. Here, we identified the tumor suppressor p53 as a key regulator that transcriptionally repressed the expression of SET in both normal and cancer cells. In addition, p53 stimulated PP2A phosphatase activity via p53-mediated transcriptional repression of SET, whereby SET-mediated inhibition of PP2A was alleviated. Moreover, targeting the interaction between SET and PP2A catalytic subunit (PP2Ac) with FTY720 enhanced stress-induced p53 activation via PP2A-mediated dephosphorylation of p53 on threonine 55 (Thr55). Therefore, our findings uncovered a previously unknown p53-SET-PP2A regulatory feedback loop. To functionally potentiate this feedback loop, we designed a combined therapeutic strategy by simultaneously administrating a p53 activator and SET antagonist in cancer cells and observed a dramatic synergistic effect on tumor suppression. Our study reveals mechanistic insight into the regulation of the oncoprotein SET and raises a potential strategy for cancer therapy by stimulating the p53-SET-PP2A feedback loop.

The 3-D calculation method of the ion flow field is required for the crossing issue of high-voltage direct-current (HVDC) transmission lines. Appropriate computational regions and boundary conditions are critical to the calculation. In this article, a novel method combining charge simulation method-flux tracing method (CSM-FTM) and finite-element method (FEM) is proposed to optimize the ion flow field calculation. The advantage of CSM-FTM in dealing with the opening domain is fully utilized. Quadratic charges are applied in CSM to ensure the calculation accuracy of the space-charge-free electric field. In addition, a hemisphere calculation region is adopted in order to model the HVDC lines with an arbitrary cross angle. The Dirichlet boundary condition on the spherical surface in the FEM calculation is obtained based on FTM. Finally, the electric field of ±800 and ±500 kV lines at a cross angle of 60° is analyzed as an example. By utilizing the proposed method, the calculation area is substantially reduced and the calculation accuracy is significantly improved.

Objective. Synovial sarcoma is a rare malignant tumor. The role of apatinib in synovial sarcoma remains unclear. In this study, we aimed to determine the biological functions and the potential molecular mechanism of action of apatinib in synovial sarcoma. Methods. SW982 cells were stimulated with apatinib. The relative expression of the genes was determined by performing qPCR. Protein levels were evaluated by western blot and immunohistochemistry assays. Proliferation, apoptosis, migration, and invasion of SW982 cells were determined by the CCK-8 assay, clone formation assay, flow cytometry, wound healing, and the transwell assay, respectively. Additionally, SW982 cells were injected into mice to induce synovial sarcoma. Results. Apatinib decreased the proliferation, migration, and invasion but increased the apoptosis of SW982 cells. Apatinib repressed tumor growth in vivo and elevated miR-34a-5p in SW982 cells. The inhibition of miR-34a-5p repressed the reduction of proliferation, migration, and invasion and also the elevation of apoptosis in apatinib-treated SW982 cells. The luciferase activity decreased after cotransfection of the miR-34a-5p mimic and the wild-type HOXA13 vector. Additionally, an increase in miR-34a-5p repressed the levels of HOXA13 mRNA and protein. Moreover, HOXA13 reversed these patterns caused by the inhibition of miR-34a-5p in apatinib-treated SW982 cells. Conclusion. Apatinib elevated miR-34a-5p and reduced HOXA13, leading to a significant decrease in proliferation, migration, and invasion, along with an enhancement of apoptosis in SW982 cells. Apatinib suppressed tumorigenesis and tumor growth in SW982 cells in vivo.

Due to the important characteristics of energy saving and carbon reduction, electric vehicles have attracted worldwide attention. It can be predicted that the power grid will be faced with the access problem of large-scale electric vehicles. In order to master the user behavior characteristics of electric vehicle load, it is necessary to establish the model based on electric vehicle charging behavior. In this paper, combined with the electric vehicle charging demand and the situational awareness results of the dispatchable resources in the station area, the characteristic indicators of the electric vehicle load are quantitatively analyzed. Situational prediction of electric vehicle load based on random forest algorithm is proposed, and the sample set is divided and trained. A simulation example is used to verify the effectiveness of the method provided in load forecasting.

Background: Ultrasound has been proved to be a promising alternative spine navigation method. High frequency ultrasound transducer has the advantage of high resolution on surface structure, but imaging at close range is difficult, especially in narrow space of the pilot-hole in pedicle.Methods: Twenty cortical bone chips were made and different size of hole with diameter of 1mm, 2mm, 3mm or 5mm was randomly carved in each bone chip. A tailored 30MHz high frequency transducer scanned bone samples at the distance of 4mm, 3mm, 2mm and 1mm. Successive transmission ringingeffect elimination, Hilbert transform and Gray-scale mapping method were utilized to process and optimize attained original images.Results: At the distance of 4mm, 3mm, 2mm and 1mm, the holes with diameter of 5mm, 3mm and 2mm could be discerned. At the distance of 1mm, only the holes with 5mm and 3mm could be clearly distinguished and the 2mm hole appeared obscure. The holes with diameter of 1mm could not be detected at any distance. The holes with diameter of 2mm were able to be detected at the distance of 1mm.Conclusions: This study indicated that the high frequency transducer had limited imaging capability at close range on the bony surface. These results lay a foundation for further developing a novel ultrasound-based spinal pedicle interior imaging and navigation system.

The crossing of two-circuit high-voltage direct current (HVdc) overhead lines will happen with the increasing number of HVdc transmission projects. The 3-D calculation is needed to predict the ion-flow field near the crossed HVdc lines. In order to decrease the difficulty of meshing near the bundle conductors, the equivalent single conductors are applied in the modeling. A roughness coefficient converting approach for equivalent conductor in Peek’s formula is presented. Thus, the corona degree of bundle conductors can be reflected by the equivalent single conductor. Afterward, the effectiveness of equivalent corona conductors in ion-flow field calculation is checked by a series of experiments and simulation. Finally, the 3-D ion-flow field distribution near the crossing of ±800 and ±500 kV HVdc overhead lines is calculated using equivalent corona conductors.

The long non-coding RNA (lncRNA) HOTAIR is an oncogene, that has been reported to be aberrantly expressed in multiple types of malignant tumor tissues. However, its expression and association with synovial sarcoma (SS) remains unclear. The present study aimed to elucidate the expression level of HOTAIR in SS tissues and also identify its role. Reverse transcription-quantitative PCR was used to detect the expression level of HOTAIR and microRNA (miR)-126 in 54 tissue samples from patients with SS, in 10 tissue samples from synovium tissues of normal patients, and in SW982 cells. The protein expression level was measured using western blot analysis and cellular immunofluorescence. Cellular proliferation, invasion and migration were assessed using MTT, Transwell and wound healing assays, respectively. HOTAIR was expressed at high levels in SS tissues. In contrast, miR-126 was expressed at low levels in SS tissues, and was negatively correlated with HOTAIR expression. HOTAIR knockdown in SW982 cells inhibited cellular proliferation in vitro, but also significantly increased the ratio of cells in the G1/G0 phase of the cell cycle, and decreased the ratio of cells in the G2/S phase. In addition, HOTAIR knockdown inhibited the invasion and migration of the SW982 cells, as observed in the Transwell and wound healing assays. Furthermore, HOTAIR knockdown increased miR-126 expression level and decreased the expression level of stromal cell-derived factor-1 (SDF-1) at the protein level. On the other hand, while miR-126-mimic decreased the protein expression level of SDF-1, miR-126-inhibitor increased its expression level in SW982 cells. Notably, HOTAIR knockdown or SDF-1 knockout significantly decreased the protein expression levels of CDK1, CDK2, cyclin D1, MMP-9, vimentin and N-cadherin, and significantly increased the protein expression levels of p21, p53 and E-cadherin in SW982 cells. HOTAIR was highly expressed in SS tissues, wherein it could promote the proliferation, invasion and migration of SS cells by increasing the expression of SDF-1 via miR-126 inhibition.

In order to improve the execution rate of the power system dispatch plan, a dispatch plan assisted decision-making considering transient safety and stability constraints is proposed. First, the principles for formulating power system transient stability control scheduling are given. Then, through the topological analysis of the expected fault location, decouple the unstable faults, formulate appropriate multi-fault adjustment timing according to the severity of the fault, and decompose the prevention and control problems of multiple fault constraints into several single fault stable control decision problems. In the end, a preventive control adjustment strategy that satisfies all transient stability constraints is obtained. Combined with parallel computing technology, the algorithm has the feasibility of online application.

Activation of PD-1 by p53 is critical for its tumor suppression in an immunity-independent manner., Cancer cell–intrinsic programmed cell death protein-1 (PD-1) has emerged as a tumor regulator in an immunity-independent manner, but its precise role in modulating tumor behaviors is complex, and how PD-1 is regulated in cancer cells is largely unknown. Here, we identified PD-1 as a direct target of tumor suppressor p53. Notably, p53 acetylation at K120/164 played a critical role in p53-mediated PD-1 transcription. Acetylated p53 preferentially recruited acetyltransferase cofactors onto PD-1 promoter, selectively facilitating PD-1 transcription by enhancing local chromatin acetylation. Reexpression of PD-1 in cancer cells inhibited tumor growth, whereas depletion of cancer cell–intrinsic PD-1 compromised p53-dependent tumor suppression. Moreover, histone deacetylase inhibitor (HDACi) activated PD-1 in an acetylated p53–dependent manner, supporting a synergistic effect by HDACi and p53 on tumor suppression via stimulating cancer cell–intrinsic PD-1. Our study reveals a mechanism for activating cancer cell–intrinsic PD-1 and indicates that p53-mediated PD-1 activation is critically involved in tumor suppression in an immunity-independent manner.

Objectives. In this study, we performed a novel type of posterior en bloc elevation cervical laminoplasty (PEEL) to keep the integrity of the posterior structure, aiming to reduce axial symptoms complicated by a conventional cervical laminoplasty procedure. Methods. Twelve human cervical cadaveric spines (C2-T1) were sequentially tested in the following order: intact condition, open-door laminoplasty (ODL) through bilateral intermuscular approach (mini-invasive ODL), PEEL, and laminectomy (LN). After bilateral transecting at the junction of lamina and lateral mass through the tubular retraction system, the PEEL procedure symmetrically elevated all the posterior structure which was further stabilized with bone grafts and titanium plates. Computed tomography (CT) scan and biomechanical testing were performed after each condition. Results. Both mini-invasive ODL and PEEL procedures were accomplished with 2 small incisions on each side. Two types of laminoplasties could enlarge the spinal canal significantly both in cross-sectional area and anteroposterior diameter comparing with intact condition. The PEEL procedure demonstrated a significantly higher enlargement rate on a canal area and a symmetrical expansion pattern. Compared with intact condition, mini-invasive ODL performed from C3-C7 demonstrated significantly decreased motion in all testing directions except the flexion range of motion (ROM); the PEEL procedure showed mild and insignificant decrease on ROM in all directions. Laminectomy resulted in a statistically significant increase in all directions except the lateral bending ROM. Conclusions. Posterior en bloc elevation cervical laminoplasty can enlarge the canal more effectively and preserve better ROM after operation than the ODL procedure. Although technically challenging, the PEEL procedure probably would decrease the common complications associated with ODL laminoplasty.

With the rapid development of P2G technology and gas turbine technology, the connection between the power system and natural gas system has become closer. Power flow calculation, as a basic application of energy network analysis, has formed mature but not uniform calculation models and methods in various energy networks. In order to promote the interdisciplinary integration of different energy networks, a new unified energy system model based on the unified energy loop theory is proposed in this paper. Particle Swarm Optimization algorithm (PSO) is used to numerically optimize the initial pressure, and the Newton method is used to solve the power flow of the electric-gas coupling integrated energy system. Finally, the feasibility and accuracy of the proposed method are verified in an electric-gas coupling system composed of the IEEE 14-node distribution system and 14-node natural gas system.

In order to solve the problem of insufficient energy supply of the on-line monitoring device of the transmission line, a sensor energy acquisition scheme directly installed on the transmission line is proposed. In the current power supply, induction power supply is a kind of energy extraction method with better practical applicability. Since the monitoring devices and electronic equipment on the transmission line are often in a strong magnetic field and high voltage environment, designing a stable and reliable power supply is the guarantee for the stable operation of the monitoring devices and electronic equipment. This paper presents a structure of energy-absorbing iron core with two semi-circular magnetic cores, and studies the magnetic saturation problem in the inductive power supply and the design of the DC output circuit.

Rationale: Synovial sarcoma (SS) is a soft tissue neoplasm that rarely occurs in the vertebral body and should be considered in the differential diagnosis in patients with SS and vertebral lesions. SS often presents as a painless mass in the spine, which may undergo slow enlargement, resulting in sustained symptoms of neurologic deficit and pain. Due to the difficulty in differentiating between SS from other soft tissue tumors and metastatic tumors, careful histological confirmation is required for definite diagnosis. Furthermore, due to its malignancy, the appropriate treatment procedure for SS should be carefully considered. Patient concerns: A 56-year-old female patient had low back pain. Radiological examination revealed bony erosion of the L-2 vertebral body, and no soft tissue mass around the lumbar spine. Diagnosis: Histopathological and immunohistochemical examination revealed SS. Interventions: The initial treatment of posterior laminectomy decompression and percutaneous vertebro plasty (PVP) was performed, however, this initial treatment course was inappropriate, but she eventually underwent L-2 complete resection and internal fixation. After the second surgery, she was treated by external beam radiation therapy. Outcomes: operation radiotherapy was finally performed. No local recurrence in L-2 vertebral body or distant metastasis was found at 1-year follow up postoperation; the neurologic symptom gradually relieved, and no other symptom was noted. And no local recurrence in L-2 vertebral body and distant metastasis was found in 1 year follow up postoperation. Lessons: Solitary spinal SS is extremely rare. Early surgery for total resection and adjuvant radiotherapy/chemotherapy should be emphasized.

Objective: To investigate the efficacy and safety of cement augmented fenestrated screws in the posterior approach for spinal metastases.Methods: A total of 52 patients with spinal metastases who underwent surgery with posterior approach separation and internal fixation with pedicle screw in the Department of Orthopaedics of the Fourth Hospital of Hebei Medical University from January 2015 to January 2017 were analyzed retrospectively. There were 28 cases in the cement augmented pedicle screw group and 24 cases in the conventional pedicle screw group. The clinical data, preoperative and postoperative pain, and neurological function between the two groups were compared. After follow-up, every 3 months, the local progression-free survival time of patients in the two groups was recorded to explore the safety of cement augmented pedicle screws in posterior separation of spinal metastases, and to analyze the difference in efficacy between the two groups.Results: There were no significant differences in sex, age, segments of the affected vertebra, Tomita score, Tokuhashi score, spinal instability neoplastic score (SINS), intraoperative blood loss and average postoperative hospital stays between the two groups. The average operation time was 161 ± 21 minutes in the cement augmented pedicle screw group and 135 ± 19 minutes in the conventional pedicle screw group, with a statistically significant difference. A total of 218 screws were implanted in the 28 patients of the cement augmented pedicle screw group, with an average of 1.3 ± 0.4 ml of cement injected into each screw. There was 1 case of cerebrospinal fluid leakage in each of the two groups, and no incision hematoma formation or infection occurred. There was no symptomatic pulmonary cement embolism in the cement augmented pedicle screw group. The preoperative VAS scores were not statistically different between the two groups. However, the VAS scores in the two groups decreased 3 months after surgery, which were 2.93 ± 1.33 and 4.17 ± 1.34, respectively, with statistical significance. The recovery of Frankel grading was found in 84.6% of all patients (44 cases in 52 patients), but there was no significant difference in Frankel grades between the two groups before and 3 months after surgery. During the follow-up period of 6-24 months, there were 10 cases of adjacent segmental metastasis (2 cases in cement augmented pedicle screw group and 8 cases in conventional pedicle screw group) and 8 cases of internal fixation failure (1 case cement augmented pedicle screw group and 7 cases in conventional pedicle screw group). The difference was statistically significant. Compared with the conventional pedicle screw group, the conventional pedicle screw group had a longer survival time of progression-free in the local and adjacent segments, and the difference was statistically significant. Conclusion: The application of cement augmented pedicle screw in surgery of spinal metastases with the posterior approach is safe, and the pain score decreases more obviously 3 months after surgery. It can effectively reduce the adjacent segmental metastasis and failure rate of internal fixation and prolong the local progression-free survival time.

Lung cancer is the leading cause of cancer-related death, and non-small cell lung cancer (NSCLC) accounts for almost 80-85% of all lung cancer cases. The transcriptional factor brachyury has been verified to promote tumor cells migrate, invade, and metastasis in various types of tumors, whereas divergent roles of brachyury on cell proliferation have been reported in several types of tumor cells. In this study, we attempted to explore the effect of brachyury on the cell cycle progression and proliferation capability of NSCLC cells. Firstly, we performed RNA-sequence and ChIP-sequence to explore underlying downstream pathways regulated by brachyury. Cell proliferation and colony formation assays were utilized to detect the effect of brachyury on the proliferation ability of two types of lung NSCLC cells: H460 and Calu-1, which represent different brachyury expression levels. Following cell cycle and cell apoptosis assays were used to investigate the mechanism by which brachyury promotes NSCLC grow and progression. RNA-sequence and ChIP-sequence (ChIP-seq) showed that one of the vital downstream pathways regulated by brachyury involves in cell cycle progression. Through cell proliferation assays and colony formation assays, we found that inhibition of brachyury could decrease the capability of proliferation in H460 cells. We also found that brachyury overexpression could prevent the transition from G0/G1 to S phase in Calu-1 cells, and brachyury knockdown could decrease the transition of G2/M phase in H460 cells. The cell apoptosis assays showed that inhibition of brachyury could promote apoptosis in H460 cells. In this study we demonstrate that brachyury and downstream target genes together involve in tumor cell cycle regulation by inducing accelerated transition through G2/M, promote tumor cell proliferation and inhibit apoptosis in lung NSCLC H460 cells. Targeting brachyury expression could be developed into a promising avenue for the prevention of lung cancer progression.

Micro-shocks may happen when the human body is close to high-voltage transmission lines. Experiments near the actual operating ±1100 kV high-voltage direct current (HVDC) lines with a metal human body model (HBM) are conducted. The voltages on the HBM and the micro-shock currents are measured. A micro-shock simulation method in the ion flow field is presented according to the measured results. Based on the simulation method, the variations of current, charge and energy on the HBM during the micro-shock process are investigated. The influences of resistance and capacitance parameters on micro-shock currents are analysed. Furthermore, a simplified simulation method is given to estimate the micro-shock currents for the potential demand of engineering practice.

Many fullerenes and carbon nanotubes have the very large electrophilic regions on their molecular surfaces. The existence of these large electrophilic regions is beyond the scope of the concept of the σ-hole and π-hole which were introduced to describe the formation of the noncovalent bonds. The inner cavities of many fullerenes and carbon nanotubes are the regions of positive electrostatic potential, and are electron-withdrawing in character. Our results clearly show that it is the electron-withdrawing cavity not the curvature of the fullerene or carbon nanotube that plays a dominant role for the formation of the large electrophilic regions on the molecular surface. The important role of the large electrophilic regions of fullerenes has been illustrated by using them to successfully explain some experimental observations in crystal engineering.