MRI measurements of brain hippocampus volume in relation to mild cognitive impairment and Alzheimer disease: A systematic review and meta-analysis.

BACKGROUND: This is the first meta-analysis conducted to compare the hippocampal volume measured by magnetic resonance imaging (MRI) in healthy normal subjects, mild cognitive impairment (MCI) and Alzheimer disease (AD), and to analyze the relationship between hippocampal volume changes and MCI and AD. METHODS: English literatures published from January 2004 to December 2006 were extracted from PubMed, Embase, Wanfang Medical, and China National Knowledge Infrastructure databases. Statistical analysis was carried out with Stata/SE 16.0 software. RESULTS: The smaller the volume of the hippocampus measured by MRI, the more severe the cognitive impairment or AD. Different MRI post-measurement correction methods have different measurement results: Left hippocampal volume measured by MRI Raw volume method is negatively correlated with MCI and AD (OR [odds ratio] = 0.58, 95%CI [confidence interval]: 0.42, 0.75) right hippocampal volume measured was not associated with MCI OR AD (OR = 0.87, 95%CI: 0.56, 1.18); left hippocampal volume measured by MRI total intracranial volume (TIV) Correction was not associated with MCI and AD (OR = 0.90, 95%CI: 0.62, 1.19), measured right hippocampal volume was not associated with MCI OR AD (OR = 0.81, 95%CI: 0.49, 1.12); left hippocampal volume measured by MRI TIV Correction was not associated with MCI and AD (OR = 0.90, 95%CI: 0.62, 1.19), measured right hippocampus volume was negatively associated with MCI and AD (OR = 0.49, 95%CI: 0.35, 0.62). CONCLUSION: The shrinkage of hippocampus volume is closely related to MCI and AD. MRI measurement of hippocampus volume is not only an auxiliary diagnostic tool for MCI and AD, but also a good prognosis assessment tool.

Robust Piezoelectricity with Spontaneous Polarization in Monolayer Tellurene and Multilayer Tellurium Film at Room Temperature for Reliable Memory.

Robust neuromorphic computing in the Big Data era calls for long-term stable crossbar-array memory cells; however, the elemental segregation in the switch unit and memory unit that inevitably occurs upon cycling breaks the compositional and structural stability, making the whole memory cell a failure. Searching for a novel material without segregation that can be used for both switch and memory units is the major concern to fabricate robust and reliable nonvolatile cross-array memory cells. Tellurium (Te) is found recently to be the only peculiar material without segregation for switching, but the memory function has not been demonstrated yet. Herein, apparent piezoelectricity is experimentally confirmed with spontaneous polarization behaviors in elementary 2D Te, even in monolayer tellurene (0.4 nm), due to the highly oriented polarization of the molecular structure and the non-centrosymmetric lattice structure. A large memory window of 7000, a low working voltage of 2 V, and high on switching current up to 36.6 µA µm-1 are achieved in the as-fabricated Te-based memory device, revealing the great promise of Te for both switching and memory units in one cell without segregation. The piezoelectric Te with spontaneous polarization provides a platform to build robust, reliable, and high-density logic-in-memory chips in neuromorphic computing.

Ion-Inserted Metal-Organic Frameworks Accelerate the Mass Transfer Kinetics in Lithium-Sulfur Batteries.

Lithium-sulfur battery promises great potential to promote the reform of energy storage field. Modified functional interlayer on separator has been recognized as efficient method to promote battery performances, mainly focusing on the entrapment and catalytic effect toward lithium polysulfide, while the mass transfer property across the interlayers has not been carefully considered. Herein, a dense layer composed of ion-inserted metal-organic frameworks is used to facilitate mass transfer across the layer and ensure high polysulfides entrapment efficiency. In situ Raman study reveals that the dense functional layer blocks the transfer of Li ions, while the ion-inserted layer can accelerate the ion-transfer kinetics and avoid the ion depletion caused polarization. As a result, a specific capacity of 742 mAh g-1 is obtained at 2 C, with the decay rate of 0.089% per cycle at 1 C over 600 cycles, demonstrating great potential for the application in advanced Li-S batteries.

Rehabilitation Evaluation of Hemiplegic Patients with Anterior Circulation Cerebral Infarction Based on Cranial Magnetic Stimulation.

Cerebral infarction is a common cerebrovascular disease in clinical medicine. Cerebral infarction in the anterior circulation accounts for about 90% of cerebral infarction. Its treatment and rehabilitation has always been a research hotspot in the medical field. Functional retraining can enhance the afferent impulses received by receptors, make the plasticity development of cerebral cortex function, and improve the loss of function. Based on the patient's individual condition, exercise therapy carries out the corresponding comprehensive functional training plan, which also includes the training of patients' daily living ability, turning over, bridge exercise, trunk rotation, etc., in order to improve the motor function of patients. The other is psychotherapy, which can cause emotional fluctuations, depression, anxiety, and other negative emotions due to the occurrence of diseases. In the rehabilitation treatment, relevant personnel can conduct psychological counseling for patients through timely and effective communication, so as to better establish patients' confidence in rehabilitation and improve the effect of rehabilitation treatment. The third is acupuncture treatment. Acupuncture is a traditional rehabilitation treatment in China. The rehabilitation effect of stroke has been proved by a large number of clinical practice. Acupuncture at Hegu, Quchi, Zusanli, and Taichong points can dredge channels and improve blood circulation. This paper mainly studies and analyzes the effect of behavior rehabilitation of hemiplegic patients with cerebral anterior circulation infarction treated by cranial magnetic stimulation. The rehabilitation treatment status of hemiplegic patients with anterior circulation cerebral infarction in a hospital was selected, and 100 cases were studied. Among them, 50 cases were treated with conventional rehabilitation therapy, and the other 50 cases were treated with cranial magnetic stimulation. The motor function, activities of daily living, and language expression ability of the two groups were compared for statistical analysis. After transcranial magnetic stimulation treatment, the abilities of the study group were better than those of the control group, P < 0.05, with statistical significance. Based on the reliable experimental data, we can draw a conclusion that the treatment of cranial magnetic stimulation has a significant effect on the rehabilitation of hemiplegic patients with cerebral anterior circulation infarction, which is higher than the conventional treatment and rehabilitation methods, and can be popularized in clinical application.

Biomimetic Nanostructure Platform for Cancer Diagnosis Based on Tumor Biomarkers.

Biomarker discovery and its clinical use have attracted considerable attention since early cancer diagnosis can significantly decrease mortality. Cancer biomarkers include a wide range of biomolecules, such as nucleic acids, proteins, metabolites, sugars, and cytogenetic substances present in human biofluids. Except for free-circulating biomarkers, tumor-extracellular vesicles (tEVs) and circulating tumor cells (CTCs) can serve as biomarkers for the diagnosis and prognosis of various cancers. Considering the potential of tumor biomarkers in clinical settings, several bioinspired detection systems based on nanotechnologies are in the spotlight for detection. However, tremendous challenges remain in detection because of massive contamination, unstable signal-to-noise ratios due to heterogeneity, nonspecific bindings, or a lack of efficient amplification. To date, many approaches are under development to improve the sensitivity and specificity of tumor biomarker isolation and detection. Particularly, the exploration of natural materials in biological frames has encouraged researchers to develop new bioinspired and biomimetic nanostructures, which can mimic the natural processes to facilitate biomarker capture and detection in clinical settings. These platforms have substantial influence in biomedical applications, owing to their capture ability, significant contrast increase, high sensitivity, and specificity. In this review, we first describe the potential of tumor biomarkers in a liquid biopsy and then provide an overview of the progress of biomimetic nanostructure platforms to isolate and detect tumor biomarkers, including in vitro and in vivo studies. Capture efficiency, scale, amplification, sensitivity, and specificity are the criteria that will be further discussed for evaluating the capability of platforms. Bioinspired and biomimetic systems appear to have a bright future to settle obstacles encountered in tumor biomarker detection, thus enhancing effective cancer diagnosis.

Coupling enhancement mechanisms, materials, and strategies for surface-enhanced Raman scattering devices.

Surface-enhanced Raman scattering (SERS) has become one of the most sensitive analytical techniques for identifying the chemical components, molecular structures, molecular conformations, and the interactions between molecules. However, great challenges still need to be addressed until it can be widely accepted by the absolute quantification of analytes. Recently, many efforts have been devoted to addressing these issues via various electromagnetic (EM), chemical (CM), and EM-CM hybrid coupling enhancement strategies. In comparison with uncoupled SERS devices, they offer key advantages in terms of sensitivity, reproducibility, uniformity, stability, controllability and reliability. This review provides an in-depth analysis of coupled SERS devices, including coupling enhancement mechanisms, materials and approaches. Finally, we also discuss the remaining bottlenecks and possible strategies for the development of coupling-enhanced SERS devices in the future.

Extracellular Vesicles in the Treatment of Parkinson's Disease: A Review.

BACKGROUND: Parkinson's disease (PD) is one of the most common neurological disorders that can severely affect the ability to perform daily activities. The clinical presentation of PD includes motor and nonmotor symptoms. The motor symptoms generally involve movement conditions like tremors, rigidity, slowness, and impaired balance. In contrast, the nonmotor symptoms are often not apparent but can affect various organ systems, such as the urinary and gastrointestinal systems, and mental health. Gene mutations and toxic environmental factors have contributed significantly to PD; nevertheless, its cause and underlying mechanism remain unknown. Currently, treatments such as dopamine agonists, RNA molecules, and antioxidants can, to some extent, alleviate the motor symptoms triggered by PD. However, these medicines cannot effectively halt ongoing dopaminergic damage, mainly because the blood-brain barrier (BBB) lowers the efficiency of drug delivery. Recently, extracellular vesicles (EVs), a novel drug delivery platform, have been widely used in various neurological diseases, including stroke and brain tumors, because of their excellent biocompatibility, their ability to penetrate the BBB without toxicity, and their target specificity. EVs thus provide a promising therapeutic for treating PD. OBJECTIVE: This review focuses on novel therapies based on EVs in practice. Herein, we briefly introduce the biogenesis, composition, isolation, and characterization of EVs, and we discuss strategies for loading therapeutic agents onto EVs and recent applications for PD treatment. Moreover, we discuss perspectives on the direction of preclinical and clinical studies regarding novel and effective therapies. METHODS: A literature search regarding PD treatment based on extracellular vesicles was performed in PubMed (updated in June 2020). Treatment, therapy, drug delivery, extracellular vesicles, and their combinations were the search queries. Both systematic reviews and original publications were included. Searched results were selected and compared based on relevance. Articles published in the last five years were given top priority. CONCLUSION: PD is a heterogeneous disease that can be treated by using pharmacologic approaches (e.g. dopamine agonists and levodopa) and nonpharmacologic approaches (e.g. music), based on symptoms and progression level in patients. Even though current treatments have demonstrated effectiveness, clinical challenges remain because the BBB reduces the medication received and lowers the efficacy of drug delivery, which impairs the treatment's effect. Therefore, EVs, as an emerging delivery platform, are highly promising for PD treatment since they can readily cross the BBB with high therapeutic efficiency through the loading or functionalization process. However, defining a safe source of EVs, reliably purifying and isolating EVs with high yield, and improving the efficacy of therapeutic loading in EVs remain challenging in this field. Therefore, future investigations should focus on generating large-scale exosomal carriers and designing new effective drugs encapsulated in EVs for better efficacy.

2D Polarized Materials: Ferromagnetic, Ferrovalley, Ferroelectric Materials, and Related Heterostructures.

The emergence of 2D polarized materials, including ferromagnetic, ferrovalley, and ferroelectric materials, has demonstrated unique quantum behaviors at atomic scales. These polarization behaviors are tightly bonded to the new degrees of freedom (DOFs) for next generation information storage and processing, which have been dramatically developed in the past few years. Here, the basic 2D polarized materials system and related devices' application in spintronics, valleytronics, and electronics are reviewed. Specifically, the underlying physical mechanism accompanied with symmetry broken theory and the modulation process through heterostructure engineering are highlighted. These summarized works focusing on the 2D polarization would continue to enrich the cognition of 2D quantum system and promising practical applications.

Record-Low Subthreshold-Swing Negative-Capacitance 2D Field-Effect Transistors.

Power consumption is one of the most challenging bottlenecks for complementary metal-oxide-semiconductor integration. Negative-capacitance field-effect transistors (NC-FETs) offer a promising platform to break the thermionic limit defined by the Boltzmann tyranny and architect energy-efficient devices. However, it is a great challenge to achieving ultralow-subthreshold-swing (SS) (10 mV dec-1 ) and small-hysteresis NC-FETs simultaneously at room temperature, which has only been reported using the hafnium zirconium oxide system. Here, based on a ferroelectric LiNbO3 thin film with great spontaneous polarization, an ultralow-SS NC-FET with small hysteresis is designed. The LiNbO3 NC-FET platform exhibits a record-low SS of 4.97 mV dec-1 with great repeatability due to the superior capacitance matching characteristic as evidenced by the negative differential resistance phenomenon. By modulating the structure and operating parameters (such as channel length (Lch ), drain-sourse bias (Vds ), and gate bias (Vg )) of devices, an optimized SS from ≈40 to ≈10 mV dec-1 and hysteresis from ≈900 to ≈60 mV are achieved simultaneously. The results provide a new potential method for future highly integrated electronic and optical integrated energy-efficient devices.

Neuroprotective Effect of Activated Protein C on Blood-Brain Barrier Injury During Focal Cerebral Ischemia/Reperfusion.

Although the effect of activated protein C (APC) on neuronal injury and neuroinflammatory responses has been extensively studied, the detailed mechanism underlying APC-protective effect in the blood-brain barrier (BBB) injury during ischemia is still not clear. In this study, the APC effect against neuroinflammatory responses was evaluated in the model of right middle cerebral artery occlusion in male Sprague-Dawley rats with 2 hours of ischemia and 22 hours of reperfusion. The results showed that APC can significantly improve the neurological function scoring and reduce the infarct volume and BBB permeability. Moreover, the expression of protein nuclear factor-kappa B (NF-κB), both in cytoplasm and nuclei, was reduced. The downstream of NF-κB activation, including tumor necrosis factor-α and interleukin-1ß secretion, was inhibited. In all, APC exerts a neuroprotective effect in focal cerebral ischemia-reperfusion in rats by inhibiting the activation and nuclear translocation of NF-κB. It may indicate a therapeutic approach for ischemic brain injury.

Ultrabroadband Photodetectors up to 10.6 µm Based on 2D Fe3 O4 Nanosheets.

The ultrabroadband spectrum detection from ultraviolet (UV) to long-wavelength infrared (LWIR) is promising for diversified optoelectronic applications of imaging, sensing, and communication. However, the current LWIR-detecting devices suffer from low photoresponsivity, high cost, and cryogenic environment. Herein, a high-performance ultrabroadband photodetector is demonstrated with detecting range from UV to LWIR based on air-stable nonlayered ultrathin Fe3 O4 nanosheets synthesized via a space-confined chemical vapor deposition (CVD) method. Ultrahigh photoresponsivity (R) of 561.2 A W-1 , external quantum efficiency (EQE) of 6.6 × 103 %, and detectivity (D*) of 7.42 × 108 Jones are achieved at the wavelength of 10.6 µm. The multimechanism synergistic effect of photoconductive effect and bolometric effect demonstrates the high sensitivity for light with any light intensities. The outstanding device performance and complementary mixing photoresponse mechanisms open up new potential applications of nonlayered 2D materials for future infrared optoelectronic devices.

Profilin 1 knockdown prevents ischemic brain damage by promoting M2 microglial polarization associated with the RhoA/ROCK pathway.

Microglial polarization to the anti-inflammatory M2 phenotype is essential in resolving neuroinflammation, making it a promising therapeutic strategy for stroke intervention. The actin cytoskeleton is known to be important for the physiological functions of microglia, including migration and phagocytosis. Profilin 1 (PFN1), an actin-binding protein, is involved in the dynamic transformation and reorganization of actin. However, the role of PFN1 in microglial polarization and ischemia/reperfusion injury is unclear. The role of PFN1 on microglial polarization was examined in vitro in BV2 microglial cells subjected to oxygen-glucose deprivation/reoxygenation (OGDR) and in vivo in male mice after transient middle cerebral artery occlusion (MCAO). Knockdown of PFN1 inhibited M1 microglial polarization and promoted M2 microglia polarization 48 hr after OGDR stimulation in BV2 cells and 7 days after MCAO-induced injury in male mice. RhoA/ROCK pathway was involved in the regulation of PFN1 during microglial polarization. Knockdown of PFN1 also significantly attenuated brain infarcts and edema, improved cerebral blood flow and neurological deficits in MCAO-injured mice. Inhibition of PFN1 effectively protected the brain against ischemia/reperfusion injuries by promoting M2 microglial polarization in vitro and in vivo.

Effect of 3-Aminobenzamide on the Ultrastructure of Astrocytes and Microvessels After Focal Cerebral Ischemia in Rats.

The disruption of blood-brain barrier (BBB) is a critical event in the formation of brain edema during early phases of ischemic brain injury. Poly(ADP-ribose) polymerase (PARP) activation, which contributes to BBB damage, has been reported in ischemia-reperfusion and traumatic brain injury. Here, we investigated the effect of 3-aminobenzamide (3-AB), a PARP-1 inhibitor, on the ultrastructure of BBB. Male Sprague Dawley rats were suffered from 90 minutes of middle cerebral artery occlusion, followed by 4.5 hours or 22.5 hours of reperfusion (R). The vehicle or 3-AB (10 mg/kg) was administered intraperitoneally (ip) 60 minutes after lacking of blood. Tissue Evans Blue (EB) levels, ultrastructures of astrocytes and microvessels, and areas of perivascular edema were examined in penumbra and core, at I 1.5 hours /R 4.5 hours and I 1.5 hours /R 22.5 hours, respectively. The severity of ultrastructural changes was graded with a scoring system in each group. We showed that 3-AB treatment significantly decreased tissue EB levels and ultrastructural scores, attenuated damages in astrocytes and microvessels, and reduced areas of perivascular edema. In conclusion, PARP inhibition may provide a novel therapeutic approach to ischemic brain injury.

Identification of Key Reversible Intermediates in Self-Reconstructed Nickel-Based Hybrid Electrocatalysts for Oxygen Evolution.

The oxygen evolution reaction (OER) has been explored extensively for reliable hydrogen supply to boost the energy conversion efficiency. The superior OER performance of newly developed non-noble metal electrocatalysts has concealed the identification of the real active species of the catalysts. Now, the critical active phase in nickel-based materials (represented by NiNPS) was directly identified by observing the dynamic surface reconstruction during the harsh OER process via combining in situ Raman tracking and ex situ microscopy and spectroscopy analyses. The irreversible phase transformation from NiNPS to α-Ni(OH)2 and reversible phase transition between α-Ni(OH)2 and γ-NiOOH prior to OER demonstrate γ-NiOOH as the key active species for OER. The hybrid catalyst exhibits 48-fold enhanced catalytic current at 300 mV and remarkably reduced Tafel slope to 46 mV dec-1 , indicating the greatly accelerated catalytic kinetics after surface evolution.

MicroRNA­217 inhibition relieves cerebral ischemia/reperfusion injury by targeting SIRT1.

MicroRNAs (miRs) have been proposed to be involved in the pathological processes of cerebral ischemia/reperfusion (CIR) injury. The present study aimed to investigate the potential role and molecular mechanisms of miR­217 in the regulation of neuronal survival in CIR injury. To perform the investigation, an in vitro cellular model of CIR injury was established by treating neurons with oxygen­glucose deprivation and reoxygenation (OGD/R). miR­217 levels in neurons were detected using reverse transcription­quantitative PCR. The association between miR­217 and sirtuin 1 (SIRT1) was identified using TargetScan and validated in a dual­luciferase reporter assay. Cell viability and apoptosis were measured using a Cell Counting Kit­8 assay and flow cytometry, respectively. The release of lactate dehydrogenase, and the production of proinflammatory factors and oxidative stress biomarkers were analyzed by ELISAs and using specific assay kits. It was revealed that miR­217 was significantly upregulated in OGD/R­treated neurons. SIRT1 was a direct target of miR­217, and was downregulated in neurons following OGD/R treatment. Downregulation of miR­217 significantly ameliorated OGD/R­induced neuronal injury, inflammatory responses and oxidative stress. The effects of miR­217 inhibitor on OGD/R treated neurons were attenuated by SIRT1 knockdown. Additionally, western blotting revealed that the SIRT1/AMP­activated protein kinase­α/NF­κB pathway was partially involved in the regulation of OGD/R­induced neuronal injury by miR­217. In conclusion, the data of the present study indicated that the downregulation of miR­217 protected neurons against OGD/R­induced injury by targeting SIRT1.

High-Performance SERS Substrate Based on Hierarchical 3D Cu Nanocrystals with Efficient Morphology Control.

Cu nanocrystals of various shapes are synthesized via a universal, eco-friendly, and facile colloidal method on Al substrates using hexadecylamine (HDA) as a capping agent and glucose as a reductant. By tuning the concentration of the capping agent, hierarchical 3D Cu nanocrystals show pronounced surface-enhanced Raman scattering (SERS) through the concentrated hot spots at the sharp tips and gaps due to the unique 3D structure and the resulting plasmonic couplings. Intriguingly, 3D sword-shaped Cu crystals have the highest enhancement factor (EF) because of their relatively uniform size distribution and alignment. This work opens new pathways for efficiently realizing morphology control for Cu nanocrystals as highly efficient SERS platforms.

Oxytocin treatment prevents marrow adiposity observed in alloxan-induced diabetic rabbits using proton MR spectroscopy.

INTRODUCTION: Oxytocin might be used therapeutically as an ally to rescue osteopathy resulting from diabetes. However, the in vivo effects of oxytocin on marrow adipogenesis in diabetes remain unknown. In this longitudinal study, we aimed to investigate the protective ef-fects of oxytocin on diabetes-induced marrow adiposity in rabbits using proton MR spectroscopy. MATERIAL AND METHODS: Forty-five female New Zealand rabbits were randomly divided into controls, diabetes, and diabetes treated with oxytocin (ip, 0.78 mg/kg) for six months. Marrow fat fraction (FF) was determined by proton MR spectroscopy at baseline, and at three and six months. Bone mineral density was measured by dual-energy X-ray absorptiometry. Serum biomarkers, glycolipid metabolism, and histological analysis of marrow adipocytes were determined. RESULTS: Oxytocin treatment had positive metabolic effects in diabetic rabbits, which was based on the changes in glucose metabolism, insulin sensitivity, and lipid profiles. The diabetic rabbits demonstrated dramatic marrow adiposity in a time-dependent manner; at three and six months the FF percentage changes from baseline were 10.1% and 25.8%, respectively (all P < 0.001). Moreover, oxytocin treatment significantly reversed FF values and quantitative parameters of marrow adipocyte in diabetic rabbits to levels of naive control rabbits. Oxytocin improved bone formation marker in diabetic rabbits compared to the saline group. Also, treatment of diabetic rabbits with oxytocin significantly mitigated bone deterioration when compared with the saline-treated diabetic group (all P < 0.05). CONCLUSIONS: Oxytocin appears to alleviate harmful effects of hyperglycaemia on marrow adiposity. Proton MR spectroscopy may be a valuable tool, providing complementary information on efficacy assessments.

[Identification of KI polyomavirus in children with lower respiratory tract infections from Zhejiang region of China].

KI polyomavirus, which was firstly discovered in 2007, is a new human polyomavirus belonging to Polyomaviridae and containing circular double-strand genomic DNA. This study was based on identification assay of KI polyomavirus reported. Total 2293 clinical sputum specimens from children under 3-years-old were collected and screened from Wenzhou Medical College affiliated Wenling Hospital, Zhejiang Province. A KI polyomavirus was detected and identified, the positive rate was 0.04%. The sequences of PCR products was identical to that of the viral capsid protein (VP1) gene derived from KI polyomavirus. The results strongly suggested that the KI polyomavirus was found firstly in Chinese children with acute lower respiratory tract infections from Zhejiang region. This study provided new information for further investigation of etiopathogenisis and diagnosis in children with lower respiratory tract infections.

[Characterization of the cytopathic effect in human bronchial epithelial cell after Human Bocavirus Infection (HBoV)].

OBJECTIVE: In this study, human bronchial epithelial cells were inoculated with positive sputum specimens of HBoV. After four days' infection, cytopathic effects (CPE) were observed by inverted microscopy. These viruses all cause typical cell damages such as rounded and shrivelled, fusion and fallout. These damages got quick following increased future degenerations. The other assay result of CPE within the infected cells were observed by inverted microscopy, have typical "owl's eye" plaque and above 90 percent hemadsorption within the infected cells by erythrocytes for hemadsorption technique. The typical fluorescence lump of nucleus within the infected cells was found by indirect immunofluorescence technique. CONCLUSION: Isolation and identification of HBoV could be done in the human bronchial epithelial cell, and we found some characterizing CPE in the human bronchial epithelial cell after HBoV infection. The above studies pave a way for studying pathogenicity of human bocavirus.

[Discovery and identification of WU polyomavirus in children from Zhejing region].

WU polyomavirus, which was firstly discovered in 2007, is a new human polyomavirus belonging to Polyomaviridae and containing circular double-stranded genomic DNA. In this study, the 278 clinical sputum specimens from children under 5 years old were collected from Wenzhou Medical College affiliated Wenling First Hospital, Zhejiang Province. Based on identification assay of WU polyomavirus previously reported, a WU polyomavirus was identified from clinical samples successfully, the positive rate was 0.4%. The sequences of PCR products were identical to that of VP2 gene and large T antigen gene derived from WU polyomavirus reported. The above results strongly suggested that the WU polyomavirus isolated was firstly found in Chinese children with acute lower respiratory tract infections. This study provides a firm basis for further research of WU polyomavirus.