pH-Activatable Charge-Reversal Polymer-Based Nanocarriers for Targeted Delivery of Antihepatoma Compound.

Chemotherapy is one of the available cancer treatments which has been successfully employed to prolong the survival of cancer patients. However, it remains a major challenge to develop effective chemotherapeutic agents by reducing off-target toxicity, improving bioavailability, and effectively prolonging blood circulation. The pH profile of tumor cells is abnormal to that of normal cells, making it a potential breakthrough for designing effective chemotherapeutic drug agents. Here, the pH-activatable charge-reversal supramolecular nanocarriers, named MI7-ß-CD/SA NPs, were prepared through a simple and "green" constructive process. MI7-ß-CD/SA NPs possess both pH-induced charge-reversal and disassembly properties that were exploited to investigate the loading, delivery, and pH-responsive controlled release of the antitumor compound celastrol (CSL). CSL@MI7-ß-CD/SA NPs displayed low hemolysis, good biocompatibility, and targeted uptake. Furthermore, CSL@MI7-ß-CD/SA NPs exhibited superior apoptosis rates against SMMC-7721 cell lines compared with CSL, when CSL@MI7-ß-CD/SA NPs and CSL were administered at a mass concentration of 5.0 µg/mL, i.e., the CSL content in CSL@MI7-ß-CD/SA NPs was relatively lower than that of intact CSL. We expected that MI7-ß-CD/SA NPs featuring pH-triggered charge reversal could offer a promising controlled release strategy that would then facilitate the clinical conversion of antitumor drugs.

N-Linked Glycosylation Plays an Important Role in Budding of Neuraminidase Protein and Virulence of Influenza Viruses.

Neuraminidase (NA) has multiple functions in the life cycle of influenza virus, especially in the late stage of virus replication. Both of hemagglutinin (HA) and NA are highly glycosylated proteins. N-linked glycosylation (NLG) of HA has been reported to contribute to immune escape and virulence of influenza viruses. However, the function of NLG of NA remains largely unclear. In this study, we found that NLG is critical for budding ability of NA. Tunicamycin treatment or NLG knockout significantly inhibited the budding of NA. Further studies showed that the NLG knockout caused attenuation of virus in vitro and in vivo Notably, the NLG at 219 position plays an important role in the budding, replication, and virulence of H1N1 influenza virus. To explore the underlying mechanism, the unfolded protein response (UPR) was determined in NLG knockout NA overexpressed cells, which showed that the mutant NA was mainly located in the endoplasmic reticulum (ER), the UPR markers BIP and p-eIF2α were upregulated, and XBP1 was downregulated. All the results indicated that NLG knockout NA was stacked in the ER and triggered UPR, which might shut down the budding process of NA. Overall, the study shed light on the function of NLG of NA in virus replication and budding.IMPORTANCE NA is a highly glycosylated protein. Nevertheless, how the NLG affects the function of NA protein remains largely unclear. In this study, we found that NLG plays important roles in budding and Neuraminidase activity of NA protein. Loss of NLG attenuated viral budding and replication. In particular, the 219 NLG site mutation significantly attenuated the replication and virulence of H1N1 influenza virus in vitro and in vivo, which suggested that NLG of NA protein is a novel virulence marker for influenza viruses.

Key Amino Acids of M1-41 and M2-27 Determine Growth and Pathogenicity of Chimeric H17 Bat Influenza Virus in Cells and in Mice.

Based on our previous studies, we show that the M gene is critical for the replication and pathogenicity of the chimeric H17 bat influenza virus (Bat09:mH1mN1) by replacing the bat M gene with those from human and swine influenza A viruses. However, the key amino acids of the M1 and/or M2 proteins that are responsible for virus replication and pathogenicity remain unknown. In this study, replacement of the PR8 M gene with the Eurasian avian-like M gene from the A/California/04/2009 pandemic H1N1 virus significantly decreased viral replication in both mammalian and avian cells in the background of the chimeric H17 bat influenza virus. Further studies revealed that M1 was more crucial for viral growth and pathogenicity than M2 and that the amino acid residues M1-41V and M2-27A were responsible for these characteristics in cells and in mice. These key residues of the M1 and M2 proteins identified in this study might be important for influenza virus surveillance and could be used to produce live attenuated vaccines in the future. IMPORTANCE The M1 and M2 proteins influence the morphology, replication, virulence, and transmissibility of influenza viruses. Although a few key residues in the M1 and M2 proteins have been identified, whether other residues of the M1 and M2 proteins are involved in viral replication and pathogenicity remains to be discovered. In the background of the chimeric H17 bat influenza virus, the Eurasian avian-like M gene from the A/California/04/2009 virus significantly decreased viral growth in mammalian and avian cells. Further study showed that M1 was implicated more than M2 in viral growth and pathogenicity in vitro and in vivo and that the key amino acid residues M1-41V and M2-27A were responsible for these characteristics in cells and in mice. These key residues of the M1 and M2 proteins could be used for influenza virus surveillance and live attenuated vaccine applications in the future. These findings provide important contributions to knowledge of the genetic basis of the virulence of influenza viruses.

The PB1 gene from H9N2 avian influenza virus showed high compatibility and increased mutation rate after reassorting with a human H1N1 influenza virus.

BACKGROUND: Reassortment between human and avian influenza viruses (AIV) may result in novel viruses with new characteristics that may threaten human health when causing the next flu pandemic. A particular risk may be posed by avian influenza viruses of subtype H9N2 that are currently massively circulating in domestic poultry in Asia and have been shown to infect humans. In this study, we investigate the characteristics and compatibility of a human H1N1 virus with avian H9N2 derived genes. METHODS: The polymerase activity of the viral ribonucleoprotein (RNP) complex as combinations of polymerase-related gene segments derived from different reassortment events was tested in luciferase reporter assays. Reassortant viruses were generated by reverse genetics. Gene segments of the human WSN-H1N1 virus (A/WSN/1933) were replaced by gene segments of the avian A2093-H9N2 virus (A/chicken/Jiangsu/A2093/2011), which were both the Hemagglutinin (HA) and Neuraminidase (NA) gene segments in combination with one of the genes involved in the RNP complex (either PB2, PB1, PA or NP). The growth kinetics and virulence of reassortant viruses were tested on cell lines and mice. The reassortant viruses were then passaged for five generations in MDCK cells and mice lungs. The HA gene of progeny viruses from different passaging paths was analyzed using Next-Generation Sequencing (NGS). RESULTS: We discovered that the avian PB1 gene of H9N2 increased the polymerase activity of the RNP complex in backbone of H1N1. Reassortant viruses were able to replicate in MDCK and DF1 cells and mice. Analysis of the NGS data showed a higher substitution rate for the PB1-reassortant virus. In particular, for the PB1-reassortant virus, increased virulence for mice was measured by increased body weight loss after infection in mice. CONCLUSIONS: The higher polymerase activity and increased mutation frequency measured for the PB1-reassortant virus suggests that the avian PB1 gene of H9N2 may drive the evolution and adaptation of reassortant viruses to the human host. This study provides novel insights in the characteristics of viruses that may arise by reassortment of human and avian influenza viruses. Surveillance for infections with H9N2 viruses and the emergence of the reassortant viruses in humans is important for pandemic preparedness.

ABCC8-related maturity-onset diabetes of the young: Clinical features and genetic analysis of one case.

OBJECTIVE: To confirm the diagnosis of a 13-year-old adolescent with familial diabetes and further examine his genetic pathogeny. RESEARCH DESIGN AND METHODS: Clinical data were collected, and genetic examination was performed. PolyPhen-2 and Mutation Taster were used to predict the deleterious effects of the variant. Clustal Omega software was used to confirm the conservation of amino acid substitutions. To examine changes in the expression of proteins, recombinant vectors were constructed, and the expression of wild-type and variant target genes was detected through quantitative polymerase chain reaction. Furthermore, the wild-type and variant eukaryotic recombinant vectors were treated with a ubiquitin degradation inhibitor (MG132) and a lysosomal degradation pathway inhibitor (CQ, 3-mA). The expression of target proteins was detected through Western blot analysis. RESULTS: The patient had hyperglycaemia (27 mmol/L), a high HbA1c level (13.1%), a decreased C-peptide level (0.63 ng/ml) and no diabetes antibodies. The patient had a family history of diabetes. The novel variation of ABCC8 c.2477G>A was detected in the proband and his relatives. The mutation was predicted to be harmful. Changes in the protein structure were observed. The ABCC8 c.2477G >A variant resulted in an increase in ABCC8 expression. Furthermore, changes in the expression of the ABCC8 variant was observed after 3-MA treatment, especially after treatment with MG132. At the follow-up, the patient's glucose level was normal without drug therapy for more than 2 years until until he started taking Trelagliptin Succinate to control hyperglycemia within the recent 6 months. CONCLUSIONS: The diagnosis of maturity-onset diabetes of the young (MODY)12 was confirmed in our patient. The ABCC8 variant inhibited both ubiquitination and autophagy lysosome degradation pathways, especially the ubiquitination degradation pathway.

A DNA tetrahedral nanomaterial-based dual-signal ratiometric electrochemical aptasensor for the detection of ochratoxin A in corn kernel samples.

Ochratoxin A (OTA) is a highly toxic food contaminant and is harmful to human beings. Herein, a ratiometric electrochemical aptasensor based on a DNA tetrahedral nanomaterial (NTH) was developed in combination with the signal tag of a zirconium metal-organic framework (UiO-66) for the detection of OTA. In the sensor, UiO-66 and a [Fe(CN)6]3-/4- electrolyte solution were used as the signal probe and the internal reference probe, respectively. In the presence of OTA, the OTA aptamer was released from the electrode due to the specific binding of OTA. Thus, signal probe P1 labeled-UiO-66 was captured on the electrode surface by hybridization with DNA NTH. Since signal probe P1 labeled-UiO-66 was close to the electrode, it leads to an increased signal current of UiO-66 at +0.9 V. As the conductivity of the modified electrode decreased, the current signal of [Fe(CN)6]3-/4- at +0.2 V also decreased. The proposed ratiometric electrochemical aptasensor could effectively eliminate external environmental influences and could avoid electrochemical background signals. The aptasensor demonstrated high specificity for OTA, and achieved a good linear range of 1 pg mL-1-100 ng mL-1 with a detection limit of 330 fg mL-1. The developed electrochemical aptamer biosensor effectively detected OTA in corn kernel samples, verifying its practical application for the determination of OTA in actual samples.

Glucometer-based electrochemical biosensor for determination of microRNA (let-7a) using magnetic-assisted extraction and supersandwich signal amplification.

A sensitive and portable biosensor is proposed for simple detection of microRNAs based on a supersandwich hybridization signal amplification strategy and a glucometer transducer. The presence of a target microRNA triggers the cascading hybridization chain reaction to create long supersandwich assemblies containing multiple biotin-labelled DNA probes. Then, large amounts of biotin-modified invertase signal molecules can attach to the supersandwich assemblies to generate an amplified signal for the glucometer readout. With such supersandwich format, a single target microRNA can introduce many biotin-invertase signal molecules, resulting in a one-to-multiple amplification effect. Thus, the accurate quantification of microRNAs can be achieved in a simple detection fashion without the requirement of expensive or precise instrumentation. The linear range of the biosensor for microRNA was from 0.05 to 100 nM with a detection limit of 48 pM. The proposed biosensor can discriminate the target microRNA from its family members with high selectivity and can be successfully applied to the detection of target microRNA spiked in serum samples with a good recovery (96.0-108.0%). Therefore, the proposed biosensor is expected to provide more information for early and accurate cancer diagnosis.

[Modified Kaixin San improves memory and synaptic damage of mice with Alzheimer's disease by modulating αCaMKâ ¡-PSD95 protein binding through inhibition of neuroinflammation:a study of mechanism].

To investigated the mechanisms underlying the effects of modified Kaixin San(MKXS) on improving memory and synaptic damage of Alzheimer's disease(AD) mouse model with conditional presenilin 1/2 conditional double knockout(PS cDKO). Specifically, 60 PS cDKO mice(3-3.5 months old) and their age-matched wild-type(WT) littermates were randomized into three groups: WT group(n=20), PS cDKO group(n=20), and PS cDKO+MKXS group(n=20). Mice in WT and PS cDKO groups were fed with standard chow and those in PS cDKO+MKXS group were given chow containing MKXS(at 2.55 g·kg~(-1)) for 60 days. Novel object reco-gnition task was employed to detect the recognition memory of mice, and Western blot to detect the protein levels of synapse-associated proteins in the hippocampus(HPC) of mice, such as NR1, NR2 A, NR2 B, p-αCaMKⅡ, tau, and p-tau. Microglial morphology in the HPC CA1 of mice was observed based on immunohistochemistry. Quantitative real time-PCR(qRT-PCR) was employed to detect the mRNA levels of the pro-inflammatory factors and synapse-associated proteins in the HPC of mice, including COX-2, iNOS, IL-1ß, IL-6, TNF-α, PSD95, NR1, NR2 A, NR2 B, and MAP2. The protein levels of IL-1ß, TNF-α, and IL-6 were tested by enzyme-linked immunosorbent assay(ELISA). The interaction between PSD95 and αCaMKⅡ and between PSD95 and p-αCaMKⅡ was tested by co-immunoprecipitation(Co-IP). The results showed that PS cDKO+MKXS demonstrated significantly higher preference index and recognition index of the new objects, lower protein level of p-tau(ser 396/404) and mRNA levels of COX-2, iNOS, TNF-α, IL-1ß, and IL-6 in HPC, higher protein levels of NR1, NR2 A, NR2 B, and p-αCaMKⅡ and mRNA levels of NR1, NR2 A, NR2 B, PSD95, and MAP2, and stronger interaction of αCaMKⅡ with PSD95 and interaction of p-αCaMKⅡ with PSD95 than the PS cDKO group. Immunohistoche-mical staining showed that MKXS inhibited the activation of microglia. In conclusion, MKXS improves memory and synaptic damage in mice with AD by modulating αCaMKⅡ-PSD95 protein binding through inhibition of neuroinflammation.

Lipotoxicity suppresses the synthesis of growth hormone in pituitary somatotrophs via endoplasmic reticulum stress.

Lipotoxicity has been shown to cause dysfunction of many organs and tissues. However, it is unclear whether lipotoxicity is harmful to the somatotrophs, a kind of cell that synthesize growth hormone (GH) in the pituitary. In this study, we performed an epidemiological study, serum levels of triglyceride (TG) and GH showed a negative correlation, even after adjustment for potential confounders. In an animal study, male Sprague-Dawley rats were fed a high-fat diet (HFD) or a control diet for 28 weeks. HFD rats showed impaired GH synthesis, resulting in a decrease in circulating GH levels. The expression of pituitary Pit-1, a key transcription factor of GH, was inhibited. We found that the inositol-requiring enzyme 1α (IRE1α) pathway of endoplasmic reticulum (ER) stress was triggered in HFD rat pituitary glands and palmitic acid-treated GH3 cells, respectively. On the contrary, applying 4-phenyl butyric acid (4-PBA) to alleviate ER stress or 4µ8c to specifically block the IRE1α pathway attenuated the impairment of both Pit-1 and GH expression. In conclusion, we demonstrated that lipotoxicity directly inhibits the synthesis of GH, probably by reducing Pit-1 expression. The IRE1α signaling pathway of ER stress may play an important role in this process.

Replication and virulence of chimeric bat influenza viruses in mammalian and avian cells and in mice.

Previous studies have shown that chimeric bat influenza viruses can be generated by reverse genetic system. However, the roles of the surface or internal genes of chimeric bat influenza viruses in viral replication and virulence in different host species were still not completely understood. In this study, we generated a chimeric H9N2 bat virus with both HA and NA surface genes from the avian A2093/H9N2 virus and compared its replication and virulence with the chimeric H1N1 bat virus with both HA and NA from the PR8/H1N1 virus in vitro and in mice. The chimeric H1N1 virus showed significantly higher replication in mammalian and avian cells and significantly higher virulence in mice than the chimeric H9N2 virus. Moreover, the chimeric H9N2 virus with the bat influenza internal M gene showed a higher replication in mammalian cells than in avian cells. While the chimeric H9N2 virus with the avian-origin viral M gene displayed a higher replication than that with the bat influenza M gene in avian cells, which likely resulted from increased receptor binding ability to α 2,3 sialic acid linked glycans of the former virus. Our study indicates that bat influenza internal genes are permissive in both mammalian and avian cells, and the bat influenza internal M gene shows more compatibility in mammals than in the avian host. Although the surface genes play more critical roles for viral replication in different host substrates, influenza M gene also potentially impacts on replication, virulence and host tropism.

Screening of tumor grade-related mRNAs and lncRNAs for Esophagus Squamous Cell Carcinoma.

BACKGROUND: The goal of our study was to screen tumor grade-related lncRNAs and mRNAs to reveal the underlying molecular mechanism of esophagus squamous cell carcinoma (ESCC). METHODS: The lncRNA and mRNA sequencing data were obtained from The Cancer Genome Atlas (TCGA). Tumor grade correlation analysis of lncRNAs and mRNAs was executed, followed by the functional enrichment analysis of all tumor grade-related mRNAs. The differentially expression mRNAs (DEmRNAs) and differentially expressed lncRNAs (DElncRNAs) were obtained. PPI network and DEmRNA-DElncRNA interaction analysis were constructed. The functional annotation of the DEmRNAs co-expressed with DElncRNAs was performed. The expression levels of the candidate genes were validated using qRT-PCR. RESULTS: A total of 1864 tumor grade-related mRNAs (846 positively related and 1018 negatively related) and 552 tumor grade-related lncRNAs (331 positively related and 221 negatively related) were obtained. The top 10 significantly grade-related mRNAs and lncRNAs included CA12, FABP4, DECR1, BAIAP2, IL1RAPL2, PPARD, LAD1, TSPAN10, LDOC1, ZNF853, RP11-25G10.2, RP11-557H15.3, RP11-521D12.5, CHKB-AS1, RP11-219B4.3, CH17-335B8.4, RP11-99 J16-A.2, CTB-111H14.1, ADNP-AS1, and JHDM1D-AS1. SFN, IL1RAPL2, and RP11-25G10.2 were overlapped from grade 1, grade 2, and grade 3. PPI network showed that top 10 proteins with higher degrees, including GNAI1, RAP2B, GNAZ, SHH, ADCY1, PRKAR2B, SH3GL1, GNA15, and ARRB1. A DElncRNAs-nearby DEmRNAs network was constructed to obtain hub lncRNAs including ADAMTS9-AS2, RP11-210 M15.2, RP11-13 K12.1, ZBED3-AS1, and RP11-25G10.2. Except for RP11-25G10.2, ADAMTS9-AS1, ZBED3-AS1, SFN, ATP1A2, and GNA15 were consistent with our TCGA analysis. CONCLUSIONS: Alterations of DEmRNAs and DElncRNAs may provide key insights into the molecular mechanisms of ESCC.

[Analysis of pathogenic variants in a Chinese pedigree affected with hyaline fibromatosis syndrome].

OBJECTIVE: To explore the clinical characteristics and genetic basis for a pair of twins affected with hyaline fibromatosis syndrome (HFS). METHODS: Clinical data of the twins were retrospectively analyzed. High-throughput sequencing was carried out to detect potential pathogenic variants. CLUSTALX was employed to analyze cross-species conservation of the mutant amino acids. Impact of the mutations was predicted by using software including PolyPhen-2 and Mutation taster. RESULTS: The pair of twins have featured growth and intelligence retardation, and were found to carry compound heterozygous variants of the ANTXR2 gene including c.1214G>A and c.1074delT, among which c.1214G>A was unreported previously. Both variants were predicted to be pathogenic. In addition to growth and mental delay, the pair of twins also featured hyperplasia of the gum and soft tissue-like masses of the auricle. The younger brother had rupture of the auricle mass during follow-up. CONCLUSION: The patients' condition can probably be attributed to the compound heterozygous variants of the ANTXR2 gene. Above finding has facilitated molecular diagnosis of the patients.

In Situ-Generated Multivalent Aptamer Network for Efficient Capture and Sensitive Electrochemical Detection of Circulating Tumor Cells in Whole Blood.

Monitoring circulating tumor cells (CTCs) in human blood can offer useful information for convenient metastasis diagnosis, prognosis, and treatment of cancers. However, it remains a substantial challenge to detect CTCs because of their particular scarcity in complex peripheral blood. Herein, we describe an in situ-generated multivalent aptamer network-modified electrode interface for efficiently capturing and sensitively detecting CTCs in whole blood by electrochemistry. Such an interface was fabricated via rolling circle amplification extension of the electrode-immobilized primer/circular DNA complexes for the yield of long ssDNA strands with many repeated aptamer segments, which could achieve efficient capture of rare CTCs in a multivalent cooperative manner. The antibody and horseradish peroxidase-functionalized gold nanoparticles further specifically associated with the surface-bound CTCs and generated electrocatalytically amplified current outputs for highly sensitive detection of CTCs with an attractive detection limit of five cells. Also, the multivalent aptamer network interface could successfully distinguish the target cells from other control cells and achieve CTC detection in whole blood, demonstrating its promising potential for monitoring different rare CTCs in human blood.

A high-sensitive sensor with HEPES-enhanced electrochemiluminescence of benzo[3]uril for Fe3+ and its application in human serum.

An electrochemiluminescence (ECL) sensor based on a benzo[3]uril-modified glassy carbon electrode with sensitized luminescence, with the coexistence of 4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid (HEPES) as the coreactant, was successfully constructed. The sensitization mechanism was proposed by analyzing the results of the control experiments for establishing the relationship of the luminescence effect with the concentration of HEPES. Under the optimized conditions, the fabricated sensor system was applied for the detection of Fe3+ in an aqueous solution with good sensitivity and selectivity. A low detection limit of 0.41 nM was achieved, indicating superior sensor performance over the previous analytical methods. The ECL sensor system was employed for the detection of Fe3+ in human serum samples to produce excellent recoveries ranging from 96.17% to 101.81%.

A Single Mutation at Position 156 in the Envelope Protein of Tembusu Virus Is Responsible for Virus Tissue Tropism and Transmissibility in Ducks.

Duck Tembusu virus (TMUV), like other mosquito-borne flaviviruses, such as Japanese encephalitis virus, West Nile virus, and Bagaza virus, is able to transmit vector-independently. To date, why these flaviviruses can be transmitted without mosquito vectors remains poorly understood. To explore the key molecular basis of flavivirus transmissibility, we compared virus replication and transmissibility of an early and a recent TMUV in ducks. The recent TMUV strain FX2010 replicated systemically and transmitted efficiently in ducks, while the replication of early strain MM1775 was limited and did not transmit among ducks. The TMUV envelope protein and its domain I were responsible for tissue tropism and transmissibility. The mutation S156P in the domain I resulted in disruption of N-linked glycosylation at amino acid 154 of the E protein and changed the conformation of "150 loop" of the E protein, which reduced virus replication in lungs and abrogated transmission in ducks. These data indicate that the 156S in the envelope protein is critical for TMUV tissue tropism and transmissibility in ducks in the absence of mosquitos. Our findings provide novel insights on understanding TMUV transmission among ducks.IMPORTANCE Tembusu virus, similar to other mosquito-borne flaviviruses such as WNV, JEV, and BAGV, can be transmitted without the presence of mosquito vectors. We demonstrate that the envelope protein of TMUV and its amino acid (S) at position 156 is responsible for tissue tropism and transmission in ducks. The mutation S156P results in disruption of N-linked glycosylation at amino acid 154 of the E protein and changes the conformation of "150 loop" of the E protein, which induces limited virus replication in lungs and abrogates transmission between ducks. Our findings provide new knowledge about TMUV transmission among ducks.

Ducks induce rapid and robust antibody responses than chickens at early time after intravenous infection with H9N2 avian influenza virus.

BACKGROUND: Compared with chickens, ducks are normally resistant to avian influenza virus without clinical signs while they habor almost all subtypes of influenza A viruses. To date, however the mechanism for duck anti-influenza has not been completely understood. The H9N2 avian influenza virus (AIV) is the most prevalent subtype of influenza A virus that infects chickens and ducks in China. However, H9N2 AIV replication and the host immune response in these domestic birds has not been systematically investigated. METHODS: In the present study, we compared the kinetics and magnitudes of antibody responses in chickens and ducks after infection with H9N2 AIV by the intranasal route or intravenous route. Furthermore, we determined the viral replication and distribution in chickens and ducks after infection with H9N2 AIV by the intravenous route. RESULTS: Our results revealed that the antibody response was rapid and robust in ducks than in chickens at early time (2-3dpi) after intravenous infection with H9N2 AIVs, while delayed and lower antibody detected in ducks than in chickens after intranasal infection with H9N2 AIVs. The virus was detected in multiple organs tissues in chickens but not in ducks infected by the intravenous route. CONCLUSIONS: Our results provide the evidence that humoral immune response could play a critical role in duck resistance for influenza, which expands our knowledge on duck anti-influenza characteristics.

CYP24A1 Variants in Two Chinese Patients with Idiopathic Infantile Hypercalcemia.

BACKGROUND: Biallelic pathogenic variants in CYP24A1 can cause idiopathic infantile hypercalcemia (HCINF). METHODS: We report 2 additional molecular abnormalities in 2 Chinese children with CHINF1. RESULTS: Biallelic variants in CYP24A1 were found in two patients. Patient One was compound heterozygous for c.449 + 1G > T and c.1426_1427delCT. Patient Two was compound heterozygous for c.1310C > A and c.1426_1427delCT. The c.1310C > A and c.449 + 1G > T were two different novel CYP24A1 variants. Multiple computational tools predicted that both impact protein function. A total of 36 variants have been previously reported in patients with HCINF1, of which 27 were classified as pathogenic or likely pathogenic and nine as uncertain clinical significance. CONCLUSION: Genetic tests are helpful in order to counsel the susceptible individuals to avoid vitamin D and take preventive measures in order to avoid complications.

Trimetallic Hybrid Nanoflower-Decorated MoS2 Nanosheet Sensor for Direct in Situ Monitoring of H2O2 Secreted from Live Cancer Cells.

In situ monitoring of hydrogen peroxide (H2O2) secreted from live cells plays a critical role in elucidating many cellular signaling pathways, and it is a significant challenge to selectively detect these low levels of endogenous H2O2. To address this challenge, we report the establishment of a trimetallic hybrid nanoflower-decorated MoS2 nanosheet-modified sensor for in situ monitoring of H2O2 secreted from live MCF-7 cancer cells. The Au-Pd-Pt nanoflower-dispersed MoS2 nanosheets are synthesized by a simple wet-chemistry method, and the resulting nanosheet composites exhibit significantly enhanced catalytic activity toward electrochemical reduction of H2O2, due to the synergistic effect of the highly dispersed trimetallic hybrid nanoflowers and the MoS2 nanosheets, thereby resulting in ultrasensitive detection of H2O2 with a subnanomolar level detection limit in vitro. Also the immobilization of the laminin glycoproteins on the surface of the nanocomposites increases its biocompatibility for cell adhesion and growth, which enables in situ electrochemical monitoring of H2O2 directly secreted from live cells for potential application of such sensor in cellular biology, clinical diagnosis, and pathophysiology.

Pathogenicity of modified bat influenza virus with different M genes and its reassortment potential with swine influenza A virus.

In our previous studies, the reassortant virus containing only the PR8 H1N1 matrix (M) gene in the background of the modified bat influenza Bat09 : mH1mN1 virus could be generated. However, whether M genes from other origins can be rescued in the background of the Bat09 : mH1mN1 virus and whether the resulting novel reassortant virus is virulent remain unknown. Herein, two reassortant viruses were generated in the background of the Bat09 : mH1mN1 virus containing either a North American or a Eurasian swine influenza virus M gene. These two reassortant viruses and the reassortant virus with PR8 M as well as the control Bat09 : mH1mN1 virus replicated efficiently in cultured cells, while the reassortant virus with PR8 M grew to a higher titre than the other three viruses in tested cells. Mouse studies showed that reassortant viruses with either North American or Eurasian swine influenza virus M gene did not enhance virulence, whereas the reassortant virus with PR8 M gene displayed higher pathogenicity when compared to the Bat09 : mH1mN1 virus. This is most likely due to the fact that the PR8 H1N1 virus is a mouse-adapted virus. Furthermore, reassortment potential between the Bat09 : mH1mN1 virus and an H3N2 swine influenza virus (A/swine/Texas/4199-2/1998) was investigated using co-infection of Madin-Darby canine kidney cells, but no reassortant viruses were detected. Taken together, our results indicate that the modified bat influenza virus is most likely incapable of reassortment with influenza A viruses with in vitro co-infection experiments, although reassortant viruses with different M genes can be generated by reverse genetics.

Effects of PB1-F2 on the pathogenicity of H1N1 swine influenza virus in mice and pigs.

Although several studies have exploited the effects of PB1-F2 in swine influenza viruses, its contribution to the pathogenicity of swine influenza viruses remains unclear. Herein, we investigated the effects of PB1-F2 on the pathogenicity of influenza virus using a virulent H1N1 A/swine/Kansas/77778/2007 (KS07) virus, which expresses a full-length PB1-F2, in mice and pigs. Using reverse genetics, we generated the wild-type KS07 (KS07_WT), a PB1-F2 knockout mutant (KS07_K/O) and its N66S variant (KS07_N66S). KS07_K/O showed similar pathogenicity in mice to the KS07_WT, whereas KS07_N66S displayed enhanced virulence when compared to the other two viruses. KS07_WT exhibited more efficient replication in lungs and nasal shedding in infected pigs than the other two viruses. Pigs infected with the KS07_WT had higher pulmonary levels of granulocyte-macrophage colony-stimulating factor, IFN-γ, IL-6 and IL-8 at 3 and 5 days post-infection, as well as lower levels of IL-2, IL-4 and IL-12 at 1 day post-infection compared to those infected with the KS07_K/O. These results indicate that PB1-F2 modulates KS07 H1N1 virus replication, pathogenicity and innate immune responses in pigs and the single substitution at position 66 (N/S) in the PB1-F2 plays a critical role in virulence in mice. Taken together, our results provide new insights into the effects of PB1-F2 on the virulence of influenza virus in swine and support PB1-F2 as a virulence factor of influenza A virus in a strain- and host-dependent manner.