The tightest self-assembled ruthenium metal-organic framework combined with proximity hybridization for ultrasensitive electrochemiluminescence analysis of paraquat.

Metal-organic frameworks (MOFs), as porous materials, have great potential for exploring high-performance electrochemiluminescence (ECL) probes. However, the constrained applicability of MOFs in the realm of ECL biosensing is primarily attributed to their inadequate water stability, which consequently impairs the overall ECL efficiency. Herein, we developed a competitive ECL biosensor based on a novel tightest structural ruthenium-based organic framework emitter combining the proximity hybridization-induced catalytic hairpin assembly (CHA) strategy and the quenching effect between the Ru-MOF and ferrocene for detecting paraquat (PQ). Through a simple hydrothermal synthesis strategy, ruthenium and 2,2'-bipyrimidine (bpm) are head-to-head self-assembled to obtain a novel tightest structural Ru-MOF. Due to the metal-ligand charge-transfer (MLCT) effect between ruthenium and the bpm ligand and the connectivity between the internal chromophore units, the Ru-MOF exhibits strong ECL emissions. Meanwhile, the coordination-driven Ru-MOF utilizes strong metal-organic coordination bonds as building blocks, which effectively solves the problem of serious leakage of chromophores caused by water solubility. The sensitive analysis of PQ is realized in the range of 1 pg/mL to 1 ng/mL with a detection limit of 0.352 pg/mL. The tightest structural Ru-MOF driven by the coordination of ruthenium and bridging ligands (2,2'-bipyrimidine, bpm) provides new horizons for exploring high-performance MOF-based ECL probes for quantitative analysis of biomarkers.

Expert consensus on Prospective Precision Diagnosis and Treatment Strategies for Osteoporotic Fractures.

Osteoporotic fractures are the most severe complications of osteoporosis, characterized by poor bone quality, difficult realignment and fixation, slow fracture healing, and a high risk of recurrence. Clinically managing these fractures is relatively challenging, and in the context of rapid aging, they pose significant social hazards. The rapid advancement of disciplines such as biophysics and biochemistry brings new opportunities for future medical diagnosis and treatment. However, there has been limited attention to precision diagnosis and treatment strategies for osteoporotic fractures both domestically and internationally. In response to this, the Chinese Medical Association Orthopaedic Branch Youth Osteoporosis Group, Chinese Geriatrics Society Geriatric Orthopaedics Committee, Chinese Medical Doctor Association Orthopaedic Physicians Branch Youth Committee Osteoporosis Group, and Shanghai Association of Integrated Traditional Chinese and Western Medicine Osteoporosis Professional Committee have collaborated to develop this consensus. It aims to elucidate emerging technologies that may play a pivotal role in both diagnosis and treatment, advocating for clinicians to embrace interdisciplinary approaches and incorporate these new technologies into their practice. Ultimately, the goal is to improve the prognosis and quality of life for elderly patients with osteoporotic fractures.

Superior colliculus bidirectionally modulates choice activity in frontal cortex.

Action selection occurs through competition between potential choice options. Neural correlates of choice competition are observed across frontal cortex and downstream superior colliculus (SC) during decision-making, yet how these regions interact to mediate choice competition remains unresolved. Here we report that SC can bidirectionally modulate choice competition and drive choice activity in frontal cortex. In the mouse, topographically matched regions of frontal cortex and SC formed a descending motor pathway for directional licking and a re-entrant loop via the thalamus. During decision-making, distinct neuronal populations in both frontal cortex and SC encoded opposing lick directions and exhibited competitive interactions. SC GABAergic neurons encoded ipsilateral choice and locally inhibited glutamatergic neurons that encoded contralateral choice. Activating or suppressing these cell types could bidirectionally drive choice activity in frontal cortex. These results thus identify SC as a major locus to modulate choice competition within the broader action selection network.

[Clinical and imaging analysis of neurological complications in critically ill children infected with SARS-CoV-2 Omicron].

OBJECTIVE: To summarize clinical predictors and imaging characteristics of critically ill children infected with SARS-CoV-2 Omicron with neurological complications in Shenzhen during the peak of the first round of infections. METHODS: The clinical data of 11 critically ill children with neurological complications infected with SARS-CoV-2 Omicron in Shenzhen Children's Hospital from December 12 to 31, 2022, were retrospectively collected and analyzed. Laboratory test results related to liver parenchymal injury, histiocytic injury, inflammation, and coagulation function were collected, and imaging characteristics including CT and/or magnetic resonance imaging (MRI) were analyzed. The differences in CT/MRI score, acute necrotizing encephalopathy severity scale (ANE-SS) score and total score (CT/MRI score + ANE-SS score) were compared between the two groups with different prognosis during hospitation. RESULTS: Among 11 children, 7 were male and 4 were female. The age ranged from 10 months to 16 years. There were 5 cases of acute necrotizing encephalopathy (ANE) and 6 cases of acute fulminant cerebral edema (AFCE). During hospitalization, 3 patients survived and 8 patients died of multiple organ dysfunction syndrome (MODS), including 2 cases of ANE and 6 cases of AFCE. All cases had fever (> 38.5 centigrade), and 3 cases had ultra-high fever (> 41 centigrade). Within 48 hours of onset, all cases had disorders of consciousness and 9 cases had seizures. The 8 dead children had complications with multisystem involvement, including shock, respiratory failure, disseminated intravascular coagulation (DIC), liver failure, renal failure or myocardial damage, and the laboratory predictors related to hepatocellular injury [alanine aminotransferase (ALT), aspartate aminotransferase (AST)], histocyte injury [creatine kinase (CK), lactate dehydrogenase (LDH)], inflammation [procalcitonin (PCT), interleukin-6 (IL-6), serum ferritin (SF)], coagulation function (D-dimer) and blood glucose (Glu) increased in different quantities, of which PCT was specifically increased in 6 cases with AFCE, PLT was specifically decreased in 3 cases with AFCE, and ALT and LDH were significantly increased in 2 cases with ANE. Imaging analysis showed subarachnoid hemorrhage, basal ganglia and thalamus lesions in all 6 cases with AFCE, while thalamus lesions in all 5 cases with ANE. The ANE-SS score of 8 deceased children ranged from 2 to 7 (of which 6 cases were ≥ 5), and the ANE-SS score of 3 surviving children ranged from 0 to 2. Eight dead children had a CT/MRI score of 1-4 (of which 6 cases were 4), and 3 surviving children had a CT/MRI score of 1-2 (of which 2 cases were 1). The total score of 8 deceased children was 6-10 (of which 6 cases ≥ 8), and 3 surviving children was 1-4. CONCLUSIONS: The neurological complications of critically ill children infected with SARS-CoV-2 Omicron in Shenzhen progressed rapidly to ANE and AFCE, with high mortality. High fever (> 40 centigrade), convulsion/disturbance of consciousness, and multiple organ failure were the most common symptoms in ANE and AFCE cases. PCT increased and PLT decreased specifically in AFCE cases. Poor prognosis (death) was more common in age < 4 years old, predictors of ALT, AST, CK, LDH, PCT, D-dimer, Glu, IL-6 increased significantly, PLT decreased significantly. The common imaging feature of ANE and AFCE is the involvement of dorsal thalamus, a new imaging sign of AFCE (subarachnoid hemorrhage) was found. The higher the ANE-SS score, CT/MRI score and total score, the greater the risk of death.

Ultrasensitive quantitation of Paraquat based on a small molecule-induced dual-cycle amplification strategy.

Paraquat (PQ) is a typical biotoxic small molecule. Knowledge of how to directly introduce it into cyclic amplification rather than transform it into a secondary target is lacking in current analytical methods. Considering the urgent need for trace pesticide residue detection and the inherent defects of small molecule analysis, a CRISPR/Cas12a-driven small molecule-induced dual-cycle strategy was developed based on the immune competition method. The key to signal amplification is the mutual activation and acceleration between Cycle 1 triggered by the small molecule and Cycle 2 driven by CRISPR/Cas12a. Impressively, small molecules have been successfully incorporated into the dual-cycle strategy, which achieves a low detection limit (3.1 pg/mL) and a wide linear range (from 10 pg/mL to 50 µg/mL). Moreover, the designed biosensor was successfully employed to evaluate the PQ residual level in real samples and showed effective implementation for the bioanalysis of small molecule targets and pesticide residue-related food safety.

Superior colliculus cell types bidirectionally modulate choice activity in frontal cortex.

Action selection occurs through competition between potential choice options. Neural correlates of choice competition are observed across frontal cortex and downstream superior colliculus (SC) during decision-making, yet how these regions interact to mediate choice competition remains unresolved. Here we report that cell types within SC can bidirectionally modulate choice competition and drive choice activity in frontal cortex. In the mouse, topographically matched regions of frontal cortex and SC formed a descending motor pathway for directional licking and a re-entrant loop via the thalamus. During decision-making, distinct neuronal populations in both frontal cortex and SC encoded opposing lick directions and exhibited push-pull dynamics. SC GABAergic neurons encoded ipsilateral choice and glutamatergic neurons encoded contralateral choice, and activating or suppressing these cell types could bidirectionally drive push-pull choice activity in frontal cortex. These results thus identify SC as a major locus to modulate choice competition within the broader action selection network.

A novel photoelectrochemical strategy for sequence-spot bispecific analysis of N6-methyladenosine modification based on proximity ligation-triggered cascade amplification.

N6-methyladenosine (m6A) modification as the most prevalent mammalian RNA internal modification has been considered as the invasive biomarkers in clinical diagnosis and biological mechanism researches. It is still challenged to explore m6A functions due to technical limitations on base- and location-resolved m6A modification. Herein, we firstly proposed a sequence-spot bispecific photoelectrochemical (PEC) strategy based on in situ hybridization mediated proximity ligation assay for m6A RNA characterization with high sensitivity and accuracy. Firstly, the target m6A methylated RNA could be transferred to the exposed cohesive terminus of H1 based on the special self-designed auxiliary proximity ligation assay (PLA) with sequence-spot bispecific recognition. The exposed cohesive terminus of H1 could furtherly trigger the next catalytic hairpin assembly (CHA) amplification and in situ exponential nonlinear hyperbranched hybridization chain reaction for highly sensitive monitoring of m6A methylated RNA. Compared with conventional technologies, the proposed sequence-spot bispecific PEC strategy for m6A methylation of special RNA based on proximity ligation-triggered in situ nHCR performed improved sensitivity and selectivity with a detection limit of 53 fM, providing new insights into highly sensitive monitoring m6A methylation of RNA in bioassay, disease diagnosis and RNA mechanism.

Expert consensus on the bone repair strategy for osteoporotic fractures in China.

Osteoporotic fractures, also known as fragility fractures, are prevalent in the elderly and bring tremendous social burdens. Poor bone quality, weak repair capacity, instability, and high failure rate of internal fixation are main characteristics of osteoporotic fractures. Osteoporotic bone defects are common and need to be repaired by appropriate materials. Proximal humerus, distal radius, tibia plateau, calcaneus, and spine are common osteoporotic fractures with bone defect. Here, the consensus from the Osteoporosis Group of Chinese Orthopaedic Association concentrates on the epidemiology, characters, and management strategies of common osteoporotic fractures with bone defect to standardize clinical practice in bone repair of osteoporotic fractures.

Continuous renal replacement therapy combined with double filtration plasmapheresis in the treatment of severe lupus complicated by serious bacterial infections in children: A case report.

There are few reports available on the combination therapy of continuous renal replacement therapy (CRRT) and double filtration plasmapheresis (DFPP) in patients with systemic lupus erythematosus (SLE) complicated by severe bacterial infections, especially in children. A 14-year-old female child with recurrent SLE complicated by severe sepsis-induced multiple organ dysfunction syndrome was administered CRRT combined with DFPP for blood purification in addition to routine immunosuppressant therapy. The changes in autoantibodies, cytokines, and coagulation function indexes of the patient before and after treatment were compared to explore the effect of such therapy on progression and prognosis. After DFPP therapy, significant decreases in the levels of double-stranded DNA antibody, cytokines interleukin (IL)-6, IL-10, and procalcitonin (PCT) were observed. Fibrinogen (Fib) decreased and needed to be replenished following DFPP. After CRRT combined with DFPP, the patient began to urinate sparingly (urine volume was < 50 mL/day) at the seventh week, the urine volume was > 400 mL/day (up to 560 mL/day) at the ninth week (63 days), and the urine volume was >1,000 mL/day at the tenth week, at which time the renal function had fully recovered. DFPP may reduce the plasma Fib concentration, which needs to be replenished in a timely manner. CRRT combined with DFPP shows efficacy in patients with SLE, but the coagulation function requires close monitoring.

Design of an all-optical multi-logic operation-integrated metamaterial-based terahertz logic gate.

Terahertz logic gates play a vital role in optical signal processing and terahertz digitization. Herein, a strategy to design an all-optical terahertz logic gate device composed of metamaterials with a semiconductor-metal hybrid is proposed; accordingly, a concrete logic gate composed of Ge embedded-in Au stripe supported by a Si board is presented theoretically. Simulation results reveal the dependence of the terahertz transmission spectra on the different illuminations in the device. Based on the illumination-transmission response, the designed device can realize the NOR or OR Boolean operation. The effects of the width of the Ge-Au stripe as well as the Si board on the transmission spectra and logic performance were also investigated.

Thalamus-driven functional populations in frontal cortex support decision-making.

Neurons in frontal cortex exhibit diverse selectivity representing sensory, motor and cognitive variables during decision-making. The neural circuit basis for this complex selectivity remains unclear. We examined activity mediating a tactile decision in mouse anterior lateral motor cortex in relation to the underlying circuits. Contrary to the notion of randomly mixed selectivity, an analysis of 20,000 neurons revealed organized activity coding behavior. Individual neurons exhibited prototypical response profiles that were repeatable across mice. Stimulus, choice and action were coded nonrandomly by distinct neuronal populations that could be delineated by their response profiles. We related distinct selectivity to long-range inputs from somatosensory cortex, contralateral anterior lateral motor cortex and thalamus. Each input connects to all functional populations but with differing strength. Task selectivity was more strongly dependent on thalamic inputs than cortico-cortical inputs. Our results suggest that the thalamus drives subnetworks within frontal cortex coding distinct features of decision-making.

Hyperbaric Oxygen Improves the Survival and Angiogenesis of Fat Grafts after Autologous Fat Transplantation.

Objective: Currently, autologous fat transplantation (AFT) still has a low graft survival rate. Elevation of the AFT graft survival rate is a challenge. This study investigated the effect of hyperbaric oxygen (HBO) on AFT. Methods: Twelve adult male SD rats were randomly divided into two groups after AFT: the control group (n = 6) and the HBO group (n = 6). The rats were killed at 7, 14, and 28 days after transplantation to take the transplanted adipose tissues. The volume and weight of the tissues were detected. The pathological changes in the adipose tissues were observed after H&E staining. Microvessel density and levels of transforming growth factor- (TGF-) ß, tumor necrosis factor- (TNF-) α, and malondialdehyde (MDA) in the transplanted adipose tissues were measured with CD31 immunohistochemical stain, ELISA, and biochemical reagents, respectively. Additionally, the protein expression levels of vascular endothelial growth factor- (VEGF-) A and platelet-derived growth factor- (PDGF) A in the adipose tissues were detected by Western blot. Results: HBO significantly preserved the volume and weight of the transplanted adipose tissue (p < 0.01) and maintained the pathological structure of the transplanted adipose tissue. HBO therapy was effective in reducing inflammatory factor (TGF-ß and TNF-α) levels and oxidative stress (MDA) in the transplanted adipose tissue (p < 0.01) and significantly increased the level of CD31 and angiogenesis-related factors including VEGF-A and PDGF-A (p < 0.01) to promote angiogenesis. Conclusion: HBO therapy regulated the immune response of fat grafts, stimulated their angiogenesis, and ultimately promoted their survival after AFT.

[Prognostic Factors Analysis of Children with Hemophagocytic Lymphohistiocytosis].

OBJECTIVE: To analyze the risk factors affecting prognosis of children with hemophagocytic lymphohistiocytosis (HLH). METHODS: The clinical manifestations and laboratory data of 143 HLH children who met the HLH-2004 diagnostic criteria in Shenzhen Children's Hospital from January 2009 to May 2017 were retrospectively analyzed, and the independent factors affecting prognosis were also analyzed. RESULTS: The median age of 143 HLH children was 1.9 (0.1-14.3) years old, and the median follow-up time was 6.7 years (1 day - 11.9 years). The overall survival rate of 1 month, 1 year, and 10 years was (87.4±5.5)%, (81.1±6.5)%, and (81.1±6.5)%, respectively. The deaths occurred within 1 year after onset. Multivariate analysis showed that central nervous system (CNS) involvement (P=0.047), low hemoglobin (P=0.002), prolonged activated partial thromboplastin time (APTT) (P<0.001), high triglyceride (P=0.005) were all the independent risk factors affecting survival of the children. Receiver operating characteristic curve indicated that APTT (AUC=0.753, P<0.001) was more valuable than other risk factors in predicting death of the children. The cut-off value of APTT was 56.6 s, and the sensitivity and specificity of which was 55.6% and 89.7%, respectively. CONCLUSION: Hypohemoglobinemia, prolonged APTT, hypertriglyceridemia, and CNS involvement the risk factors affecting prognosis of HLH, and prolonged APTT shows a strong predictive value for death.

Use of a modified tracheal tube in a child with traumatic bronchial rupture: A case report and review of literature.

BACKGROUND: Trauma is one of the leading causes of death in the pediatric population. Bronchial rupture is rare, but there are potentially severe complications. Establishing and maintaining a patent airway is the key issue in patients with bronchial rupture. Here we describe an innovative method for maintaining a patent airway. CASE SUMMARY: A 3-year-old boy fell from the seventh floor. Oxygenation worsened rapidly with pulse oxygen saturation decreasing below 60%, as his heart rate dropped. Persistent pneumothorax was observed with insertion of the chest tube. Fiberoptic bronchoscopy was performed, which confirmed the diagnosis of bronchial rupture. A modified tracheal tube was inserted under the guidance of a fiberoptic bronchoscope. Pulse oxygen saturation improved from 60% to 90%. Twelve days after admission, right upper lobectomy was performed using bronchial stump suture by video-assisted thoracic surgery without complications. A follow-up chest radiograph showed good recovery. The child was discharged from hospital three months after admission. CONCLUSION: A modified tracheal tube could be selected to ensure a patent airway and adequate ventilation in patients with bronchial rupture.

Pyopneumothorax from coinfection by Trichomonas tenax and Geotrichum capitatum in a child from China: a case report.

BACKGROUND: Trichomonas tenax may appear in the oral cavity of humans due to poor dentition or oral hygiene. Pyopneumothorax is a serious complication of lower respiratory tract infections that very rarely can be caused by a trichomonad species in predisposed individuals. We report a rare case of pleurisy due to T. tenax with coinfection by a fungus. CASE PRESENTATION: We describe a 16-year-old patient with cerebral palsy who presented with severe pyopneumothorax. T. tenax was identified by microscopic examination of the pleural effusion and next-generation sequencing. We also identified Geotrichum capitatum in the pleural effusion and bronchoalveolar lavage fluid cultures. Treatment with voriconazole and metronidazole successfully eliminated these pathogens and relieved the clinical symptoms. A literature review indicated this is the first reported case of pleurisy due to T. tenax with coinfection by a fungus. CONCLUSION: The rarity of pyopneumothorax caused by T. tenax coinfection with a fungus should not be overlooked in the clinic. These patients should be and treated in a timely manner.

Circuit Mechanisms Underlying Epileptogenesis in a Mouse Model of Focal Cortical Malformation.

The way in which aberrant neural circuits contribute to epilepsy remains unclear. To elucidate this question, we dissected the circuit mechanisms underlying epileptogenesis using a mouse model of focal cortical malformation with spontaneous epileptiform discharges. We found that spontaneous spike-wave discharges and optogenetically induced hyperexcitable bursts in vivo were present in a cortical region distal to (>0.7 mm) freeze-lesion-induced microgyrus, instead of near the microgyrus. ChR2-assisted circuit mapping revealed ectopic inter-laminar excitatory input from infragranular layers to layers 2/3 pyramidal neurons as the key component of hyperexcitable circuitry. This hyperactivity disrupted the balance between excitation and inhibition and was more prominent in the cortical region distal to the microgyrus. Consistently, the inhibition from both parvalbumin-positive interneurons (PV) and somatostatin-positive interneurons (SOM) to pyramidal neurons were altered in a layer- and site-specific fashion. Finally, closed-loop optogenetic stimulation of SOM, but not PV, terminated spontaneous spike-wave discharges. Together, these results demonstrate the occurrence of highly site- and cell-type-specific synaptic reorganization underlying epileptic cortical circuits and provide new insights into potential treatment strategies.

[Clinical features of children with influenza and plastic bronchitis: an analysis of 63 cases].

OBJECTIVE: To study the clinical features of children with influenza and plastic bronchitis (PB). METHODS: A retrospective analysis was performed on the medical data of 63 children with influenza and PB, including clinical manifestations, laboratory examination results, imaging findings, treatment, and outcome. RESULTS: Among the 63 children, there were 52 boys (83%) and 11 girls (17%), and 42 children had influenza A and 21 had influenza B. Among these children, 38 (60%) aged 3-6 years, and 15 (24%) had underlying diseases. The main clinical manifestations were high fever (90%), cough (95%), and shortness of breath (73%). Twenty-four children (38%) were found to have atelectasis by imaging examination. Auscultation showed that 16 children (25%) had no rales in the lungs. Of all children, 41 were admitted to the intensive care unit, and 32 required mechanical ventilation. All children underwent fiberoptic bronchoscopy and alveolar lavage. Among the 63 children, 60 recovered and 3 died. CONCLUSIONS: Influenza with PB is often observed in boys and preschool children. For influenza children with shortness of breath, even if there is no atelectasis on chest X-ray or no rales are found by auscultation, the possibility of PB still needs to be considered.

Identification and Treatment of Tuberculosis in Pediatric Recipients of Allogeneic Hematopoietic Stem Cell Transplantation: Case Series and Review of the Literature.

BACKGROUND: Tuberculosis is a rare but life-threatening complication in patients who received hematopoietic stem cell transplantation. Early identification and intervention are essential to prevent severe complications. CASE PRESENTATION: We report two pediatric patients who developed tuberculosis after receiving hematopoietic stem cell transplantation for thalassemia major among 330 recipients between January 2012 and August 2019. Patient A presented with pulmonary tuberculosis and patient B presented with lymph node tuberculosis mimicking post-transplantation lymphoproliferative disorder associated with Epstein-Barr virus reactivation. Patient B's condition was deteriorated, and shortly after the initiation of anti-tuberculosis therapy, the patient was found to have disseminated pulmonary tuberculosis. Patient B was also found to have tuberculous granulomas, an uncommon manifestation of tuberculosis causing severe airway obstruction. Both patients developed critical respiratory failure and required mechanical ventilation; however, they recovered with almost full resolution of pulmonary lesions after multiple treatment adjustments. CONCLUSION: Tuberculosis must be carefully evaluated in all pediatric patients that receive hematopoietic stem cell transplantation, regardless of the identification of other pathogens. Prophylactic tuberculosis therapy should be considered for high-risk pediatric hematopoietic stem cell transplantation recipients from tuberculosis-endemic regions.

The Safety and Effectiveness of Intravenous Contrast-Enhanced Sonography in Chinese Children-A Single Center and Prospective Study in China.

Background and Objective: Intravenous contrast-enhanced ultrasound (CEUS), using the second-generation ultrasound contrast agent SonoVue®, has been widely used in adults. In 2016, it was approved for pediatric applications by the American Food and Drug Administration (FDA). However, it has not been approved by the Chinese Food and Drug Administration (CFDA). The objective of the study was to evaluate the safety and effectiveness of CEUS in children prospectively at a single center in China. Methods: A total of 312 cases of Chinese children were enrolled in clinical trials. Contrast agent was given intravenously with two different doses, including 2.4 ml/time and 0.03 ml/kg. All CEUS was performed for evaluating adverse effect and the diagnostic accuracy compared with the pathology and enhanced CT. Results: All 312 subjects underwent CEUS successfully. The dose of contrast agent for CEUS was 2.4 ml between November 2015 and June 2016, which was modified to 0.03 ml/kg between July 2016 and April 2019, according to the recommendation of the FDA. With the two different doses of the contrast agent, the heart rate, respiration rate, oxygen saturation, and blood pressure of the participants had no statistically significant difference (P > 0.05) before and after administration. The blood pressure had been significantly decreased in participants who received combined anesthetic administration. Following 600 intravenous injections of the CEUS, there were three cases of transient rash and three cases of hypotension (n = 6, 1.92%). The six recovered quickly after receiving intravenous methylprednisolone and epinephrine. Most of the studies were performed for evaluating renal microcirculation and assisting renal biopsy (192/312 [61.5%]), which together had a 98.9% effectiveness in the identification of pathology in the specimens. Some studies were conducted to identify a mass in the liver, retroperitoneum, abdominal cavity, kidneys, testicles, thyroid, and so on (99/312 [31.4%]), which had a 97.6% accuracy. The other studies were conducted to identify trauma, vascular malformation, infection, hemorrhage, and so on (21/312 [6.73%]), which had a similar accuracy to enhanced CT. Conclusion: The adverse effects of CEUS in children are similar to that in adults. The results indicate that it is safe to use SonoVue® for CEUS in pediatric patients.

How Leader-Member Exchange Affects Knowledge Sharing Behavior: Understanding the Effects of Commitment and Employee Characteristics.

Although leadership is considered a key factor in affecting employees' knowledge sharing behavior (KSB), previous literature has mainly focused on the direct relationship between it and KSB, neglecting the mediators and moderators in this relationship. To address this issue, this study explores when and how leader-member exchange (LMX) promotes KSB by examining affective commitment (AC) as mediator and employee general self-efficacy (GSE) and internal locus of control (ILOC) as boundary conditions. In addition, although these two positive self-view variables (i.e., GSE and ILOC) both exhibit positive effects on various work-related outcomes, based on self-verification theory, we posit that they may exhibit different moderating effects in the LMX-AC-KSB relationship. We empirically validated this moderated mediated model using data collected from 231 supervisor-subordinate pairs from an information technology company in China. The results show that GSE amplifies the mediated relationship between LXM and KSB via AC, but ILOC weakens this mediated relationship. Our study elucidates when and how LMX can effectively facilitate KSB and sheds new and nuanced light on the conceptual distinction between GSE and ILOC. The results of this study might direct managers how to develop relationships with their subordinates and how to maximally facilitate subordinates' KSB.