Rickettsia symbionts spread via mixed mode transmission, increasing female fecundity and sex ratio shift by host hormone modulating.

Heritable symbionts are common among animals in nature, but the molecular mechanisms underpinning symbiont invasions of host populations have been elusive. In this study, we demonstrate the spread of Rickettsia in an invasive agricultural pest, the whitefly Bemisia tabaci Mediterranean (MED), across northeastern China from 2018 to 2023. Here, we show that the beneficial symbiont Rickettsia spreads by manipulating host hormone signals. Our analyses suggest that Rickettsia have been horizontally acquired by B. tabaci MED from another invasive whitefly B. tabaci Middle East-Asia Minor 1 during periods of coexistence. Rickettsia is transmitted maternally and horizontally from female B. tabaci MED individuals. Rickettsia infection enhances fecundity and results in female bias among whiteflies. Our findings reveal that Rickettsia infection stimulates juvenile hormone (JH) synthesis, in turn enhancing fecundity, copulation events, and the female ratio of the offspring. Consequently, Rickettsia infection results in increased whitefly fecundity and female bias by modulating the JH pathway. More female progeny facilitates the transmission of Rickettsia. This study illustrates that the spread of Rickettsia among invasive whiteflies in northeastern China is propelled by host hormone regulation. Such symbiont invasions lead to rapid physiological and molecular evolution in the host, influencing the biology and ecology of an invasive species.

Exploring charge generation and separation in tandem organic light-emitting diodes based on magneto-electroluminescence.

5,6,11,12-tetraphenylnaphthacene (rubrene) exhibits resonant energy properties (ES1,rub≈ 2ET1,rub), resulting in rubrene-based organic light-emitting diode (OLED) devices that undergo the singlet fission (STT) process at room temperature. This unique process gives rise to a distinct magneto-electroluminescence (MEL) profile, differing significantly from the typical intersystem crossing (ISC) process. Therefore, in this paper, we investigate charge generation and separation in the interconnector, and the mechanism of charge transport in tandem OLEDs at room temperature using MEL tools. We fabricate tandem OLEDs comprising green (Alq3) and yellow (Alq3:rubrene) electroluminescence (EL) units using different interconnectors. The results demonstrate that all devices exhibited significant rubrene emission. However, the MEL did not exhibit an STT process with an increasing magnetic field, but rather a triplet-triplet annihilation (TTA) process. This occurrence is attributed to direct carrier trapping within doped EL units, which hinders the transport of rubrene trapped charges, consequently prolonging the lifetime of triplet excitons (T1,rub). Thus, the increased T1,rubconcentration causes TTA to occur at room temperature, causing the rapid decrease of MEL in all devices under high magnetic fields. In devices where only the TTA process occurs, the TTA increases with the increasing current. Consequently, the high magnetic field of devices A-C is only related to TTA. Notably, there exists a high magnetic field TTA of device D in the Alq3/1,4,5,8,9,11-Hexaazatriphenylene-hexacarbonitrile interconnector regardless of the current. This occurs because both EL units in the device emit simultaneously, resulting in the triplet-charge annihilation process of Alq3in the high magnetic field of the MEL. Moreover, the rapid increase in MEL at low magnetic field across all devices is attributed to the ISC between Alq3polaron pairs. This entire process involves Förster and Dexter energy transfer. This article not only provides novel insights into charge generation and separation in the interconnector but also enhances our understanding of the microscopic mechanisms in tandem OLED devices.

Lysine provisioning by horizontally acquired genes promotes mutual dependence between whitefly and two intracellular symbionts.

Horizontal gene transfer is widespread in insects bearing intracellular symbionts. Horizontally transferred genes (HTGs) are presumably involved in amino acid synthesis in sternorrhynchan insects. However, their role in insect-symbiont interactions remains largely unknown. We found symbionts Portiera, Hamiltonella and Rickettsia possess most genes involved in lysine synthesis in the whitefly Bemisia tabaci MEAM1 although their genomes are reduced. Hamiltonella maintains a nearly complete lysine synthesis pathway. In contrast, Portiera and Rickettsia require the complementation of whitefly HTGs for lysine synthesis and have lysE, encoding a lysine exporter. Furthermore, each horizontally transferred lysine gene of ten B. tabaci cryptic species shares an evolutionary origin. We demonstrated that Hamiltonella did not alter the titers of Portiera and Rickettsia or lysine gene expression of Portiera, Rickettsia and whiteflies. Hamiltonella also did not impact on lysine levels or protein localization in bacteriocytes harboring Portiera and ovaries infected with Rickettsia. Complementation with whitefly lysine synthesis HTGs rescued E. coli lysine gene knockout mutants. Silencing whitefly lysA in whiteflies harboring Hamiltonella reduced lysine levels, adult fecundity and titers of Portiera and Rickettsia without influencing the expression of Hamiltonella lysA. Furthermore, silencing whitefly lysA in whiteflies lacking Hamiltonella reduced lysine levels, adult fecundity and titers of Portiera and Rickettsia in ovarioles. Therefore, we, for the first time, demonstrated an essential amino acid lysine synthesized through HTGs is important for whitefly reproduction and fitness of both obligate and facultative symbionts, and it illustrates the mutual dependence between whitefly and its two symbionts. Collectively, this study reveals that acquisition of horizontally transferred lysine genes contributes to coadaptation and coevolution between B. tabaci and its symbionts.

Realizing high efficiency and luminance in green, yellow and blue organic light emitting diode by deoxyribonucleic acid.

Although the effect of the electron blocking layer (EBL) material, deoxyribonucleic acid (DNA), on the electroluminescence (EL) performance of organic light-emitting diodes (OLEDs) has been studied, the process of DNA regulation of exciton recombination region within the device is still unclear. Herein, devices with and without EBL were fabricated using different DNA spin-coating speeds, and the photoelectric performance of device were measured. By using DNA compounded with cetyltrimethyl ammonium (CTMA) as the EBL and hole buffer layer, so-called BioLEDs. The DNA-based green Alq3BioLEDs achieve higher luminance (39 000 cd m-2) and higher current efficiency (8.4 cd A-1), which are increased by 49% and 54%, respectively, compared to the reference OLEDs without the addition of DNA. Similarly, the maximum luminance and efficiency of yellow Rubrene BioLEDs is increased by 64% (from 12 120 to 19 820 cd m-2) and 74% (from 1.36 to 2.36 cd A-1), the luminance and efficiency of blue TCTA BioLEDs is increased by 101% and 245%. Specifically, we found that as the thickness of DNA-CTMA increases, the exciton recombination region moves towards the interface between the emitting layer (EML) and the hole transport layer (HTL). By better confining excitons within the EML, the current efficiency of the BioLEDs is effectively improved. Accordingly, we provide a possible idea for achieve high performance DNA-based BioLEDs by adding DNA-CTMA EBL and hole buffer layers. Meanwhile, as the DNA thickness increases, the exciton recombination region moves towards the EML/HTL interface, thereby enhancing the efficiency of the DNA-based BioLEDs.

Investigations on exciton recombination and annihilation in TmPyPB-ETL OLEDs using magnetic field effects.

Although the effect of the electron transport layer (ETL) material TmPyPb on the electroluminescence performance of organic light-emitting diodes (OLEDs) has been extensively studied, the process of TmPyPb regulating exciton recombination and annihilation within the device is still unclear. Here, we fabricated devices of various TmPyPb thicknesses with and without ETL. Subsequently, we measured the magneto-electroluminescence (MEL) of these devices. Specifically, at the same luminance, the triplet-charge annihilation (TQA) process is more likely to occur as the thickness of TmPyPb increases, resulting in a decrease in the maximum luminance of devices. Due to electron leakage and exciton recombination region moving towards the cathode, leading to a decrease in luminance efficiency at first and then an enhancement with an increase in the thickness of TmPyPb. Furthermore, at room temperature, the application of a large bias voltage suppresses singlet fission (SF) processes by modulating the dissociation of singlet polaron pairs (PPS) and the concentration of triplet exciton (T1). This leads to the conversion of SF to the TQA process. At low temperatures, the bias voltage and temperature can regulate the concentration and lifetime of PPS and T1. Therefore, as the temperature decreases, the transition of SF → TQA → triplet-triplet annihilation (TTA) and TQA coexistence → TTA process occurs. Moreover, MEL responses of the TmPyPb-ETL device show a W-linear pattern owing to the combined effect of the hyperfine interaction (HFI) and Zeeman splitting at 145 K. Accordingly, we explored the electroluminescence (EL) performance of TmPyPB-ETL OLEDs and investigated the evolution of SF, TQA, and TTA processes using MEL. Our study revealed the effect of exciton recombination and annihilation in OLEDs with varying thicknesses of TmPyPb.

Enhanced productivity and stability of PRV in recombinant ST-Tret1 cells.

Productivity and stability of Pseudorabies virus (PRV) are critical for the manufacture and storage of live attenuated pseudorabies vaccine. Trehalose is commonly used as a cryoprotectant to stabilize organisms during freezing and lyophilization. Trehalose transporter 1 (Tret1), derived from Polypedilum vanderplanki, can deliver trehalose with a reversible transporting direction. In this study, we demonstrated that productivity and stability of PRV proliferated in recombinant ST cells with stable expression of Tret1 were enhanced. As a result, a five-fold increase of intracellular trehalose amount was observed, and the significant increase of progeny viral titer was achieved in recombinant cells with the addition of 20 mM trehalose. Particularly, after storage for 8 weeks at 20 °C, the loss of viral titer was 0.8 and 1.7 lgTCID50/mL lower than the control group with or without the addition of trehalose. Additionally, the freeze-thaw resistance at -20 °C and -70 °C of PRV was significantly enhanced. Furthermore, according to standard international protocols, a series of tests, including karyotype analysis, tumorigenicity, and the ability of proliferation PRV, were conducted. Our results demonstrated that the recombinant ST cell with Tret1 is a promising cell substrate and has a high potential for producing more stable PRV for the live attenuated vaccine.

Pseudorabies virus infection induces endoplasmic reticulum stress and unfolded protein response in suspension-cultured BHK-21 cells.

Viral infections cause endoplasmic reticulum (ER) stress and subsequently unfolded protein response (UPR) which restores ER homeostasis. In this study, levels of proteins or transcription of three UPR pathways were examined in suspension-cultured BHK-21 cells to investigate Pseudorabies virus (PRV) infection-induced ER stress, in which glucose-related proteins 78 kD and 94 kD (GRP78 and GRP94) were upregulated. The downstream double-stranded RNA-activated protein kinase-like ER kinase (PERK) pathway was activated with upregulation of ATF4, CHOP, and GADD34, and the inositol requiring kinase 1 (IRE1) pathway was triggered by the splicing of X box-binding protein 1 (XBP1) mRNA and the enhanced expression of p58IPK and EDEM. Furthermore, our results showed that the ER stress, induced by 0.005 µM thapsigargin, promoted PRV replication in suspension-cultured BHK-21 cells, and that PRV glycoprotein B (gB) overexpression triggered the PERK and IRE1 pathways.

Remote blast-related mild traumatic brain injury is associated with differential expression of exosomal microRNAs identified in neurodegenerative and immunological processes.

BACKGROUND: Blast traumatic brain injury (TBI) and subconcussive blast exposure have been associated, pathologically, with chronic traumatic encephalopathy (CTE) and, clinically, with cognitive and affective symptoms, but the underlying pathomechanisms of these associations are not well understood. We hypothesized that exosomal microRNA (miRNA) expression, and their relation to neurobehavioral outcomes among Veterans with blunt or blast mild TBI (mTBI) may provide insight into possible mechanisms for these associations and therapeutic targets. METHODS: This is a subanalysis of a larger Chronic Effects of Neurotrauma Consortium Biomarker Discovery Project. Participants (n = 152) were divided into three groups: Controls (n = 35); Blunt mTBI only (n = 54); and Blast/blast+blunt mTBI (n = 63). Postconcussive and post-traumatic stress symptoms were evaluated using the NSI and PCL-5, respectively. Exosomal levels of 798 miRNA expression were measured. RESULTS: In the blast mTBI group, 23 differentially regulated miRNAs were observed compared to the blunt mTBI group and 23 compared to controls. From the pathway analysis, significantly dysregulated miRNAs in the blast exposure group correlated with inflammatory, neurodegenerative, and androgen receptor pathways. DISCUSSION: Our findings suggest that chronic neurobehavioral symptoms after blast TBI may pathomechanistically relate to dysregulated cellular pathways involved with neurodegeneration, inflammation, and central hormonal regulation.

Sinomenine exerts a neuroprotective effect on PD mouse model through inhibiting PI3K/AKT/mTOR pathway to enhance autophagy.

BACKGROUND: Parkinson's disease (PD), as a chronic and progressive neurodegenerative disease, is associated with autophagy. This study focused on the regulation of sinomenine (SN) on autophagy in PD and its related mechanism. METHODS: The PD mouse model was constructed by MPTP inducement, and the mouse motor function after modeling and SN treatment was examined by rotarod, grip strength, and foot printing tests. Tyrosine hydroxylase (TH)/LC3B-positive neurons in the substantia nigra pars compacta of mouse brains were detected by immunofluorescence. The expressions of proteins related to autophagy (Beclin1, p62, LC3-I and LC3-II) and phosphorylated phosphoinositide 3-kinase (PI3K)/AKT/mechanistic target of rapamycin kinase (mTOR) signaling pathway were measured by western blot. Rescue experiments were performed to determine the effects of MHY1485 (mTOR activator) on SN-treated PD mice. RESULTS: SN potentiated the motor ability in PD mice, promoted the survival of dopaminergic neurons, increased the protein expression level of Beclin1, LC3-II/LC3-I ratio and LC3B-positive neurons, lowered the protein expression level of p62 and inactivated PI3K/AKT/mTOR pathway in the substantia nigra tissue of mouse brains. Moreover, MHY1485 reversed the above effects of SN on PD mice via reactivating PI3K/AKT/mTOR pathway. CONCLUSION: SN augments the autophagy of dopaminergic neurons via inhibiting the PI3K/AKT/mTOR pathway and exerts a neuroprotective effect on PD mice.

[Application of ultrasound-guided endoscopic retrograde appendicitis therapy in children with appendix-related chronic abdominal pain]. / è¶ å£°å¼•å¯¼å† é•œä¸‹é€†è¡Œé˜‘å°¾ç‚Žæ²»ç–—æœ¯åœ¨é˜‘å°¾ç›¸å ³æ ¢æ€§è ¹ç—›æ‚£å„¿ä¸­çš„åº”ç”¨ä»·å€¼.

OBJECTIVES: To study the clinical efficacy of ultrasound-guided endoscopic retrograde appendicitis therapy in children with appendix-related chronic abdominal pain. METHODS: A retrospective analysis was performed on the medical data of 30 children with the chief complaint of chronic abdominal pain who were admitted from August 2019 to May 2021. All the children were found to have inflammation of the appendix or intracavitary stool and fecalith by ultrasound and underwent ultrasound-guided endoscopic retrograde appendicitis therapy. The medical data for analysis included clinical manifestations, endoscopic findings, white blood cell count, neutrophil percentage, length of hospital stay, and cure rate. RESULTS: Among the 30 children with chronic abdominal pain, there were 13 boys (43%) and 17 girls (57%), with a mean age of (9±3) years (range 3-15 years) at diagnosis. The median duration of the disease was 12 months, and the median length of hospital stay was 3 days. The children had a median white blood cell count of 6.7×109/L and a neutrophil percentage of 50%±13%. Fecalith and a large amount of feces were flushed out of the appendix cavity for 21 children (70%) during surgery. The follow-up rate was 97% (29/30), and the median follow-up time was 11 months (range 5-26 months). Of the 29 children, abdominal pain completely disappeared in 27 children (93%). CONCLUSIONS: Ultrasound-guided endoscopic retrograde appendicitis therapy is effective in children with chronic abdominal pain caused by feces or fecalith in the appendix cavity.

Magnon-mediated nonreciprocal microwave transmission based on quantum interference.

Nonreciprocity has always been a subject of interest and plays a key role in a variety of applications like signal processing and noise isolation. In this work, we propose a simple and feasible scheme to implement nonreciprocal microwave transmission in a high-quality-factor superconducting cavity with ferrimagnetic materials. We derive necessary requirements to create nonreciprocity in our system where a magnon mode and two microwave modes are coupled to each other, highlighting the adjustability of a static magnetic field controlled nonreciprocal transmission based on quantum interference between different transmission paths, which breaks time-reversal symmetry of the three-mode cavity magnonics system. The high light isolation adjusted within a range of different magnetic fields can be obtained by modulating the photon-magnon coupling strength. Due to the simplicity of the device and the system tunability, our results may facilitate potential applications for light magnetic sensing and coherent information processing.

Boosting Hydrogen Oxidation Activity of Ni in Alkaline Media through Oxygen-Vacancy-Rich CeO2 /Ni Heterostructures.

The search for highly efficient platinum group metal (PGM)-free electrocatalysts for the hydrogen oxidation reaction (HOR) in alkaline electrolytes remains a great challenge in the development of alkaline exchange membrane fuel cells (AEMFCs). Here we report the synthesis of an oxygen-vacancy-rich CeO2 /Ni heterostructure and its remarkable HOR performance in alkaline media. Experimental results and density functional theory (DFT) calculations indicate the electron transfer between CeO2 and Ni could lead to thermoneutral adsorption free energies of H* (ΔGH* ). This, together with the promoted OH* adsorption strength derived from the abundance of oxygen vacancies in the CeO2 species, contributes to the excellent HOR performance with the exchange current density and mass activity of 0.038 mA cmNi -2 and 12.28 mA mgNi -1 , respectively. This presents a new benchmark for PGM-free alkaline HOR and opens a new avenue toward the rational design of high-performance PGM-free electrocatalysts for alkaline HOR.

[Establishment of a congenital chloride diarrhea-associated SLC26A3 c.392C>G (p.P131R) polymorphism-expressing cell model and a preliminary analysis of its mechanism of action].

OBJECTIVE: To establish a congenital chloride diarrhea (CCD)-associated SLC26A3 c.392C>G (p.P131R) polymorphism-expressing cell model, and to investigate its biological function. METHODS: The sequence of the SLC26A3 gene in GenBank was used to design the upstream and downstream single-guide RNA (sgRNA) that could specifically recognize the 392 locus of the SLC26A3 gene, and the sgRNA was mixed with the pSpCas9-puro vector after enzyme digestion to construct an eukaryotic recombinant expression plasmid (pSpCas9-SLC26A3). Caco-2 cells were transfected with the recombinant plasmid and synthesized single-stranded DNA oligonucleotides (ssODNs), and Taqman genotyping assay and Sanger sequencing were used to identify the expression of SLC26A3 c.392C>G (p.P131R) in Caco-2 cells. Wild-type Caco-2 cells were selected as normal control group and the Caco-2 cells with successful expression of SLC26A3 c.392C>G (p.P131R) was selected as P131R group. Both groups were treated with 100 ng/mL tumor necrosis factor-α (TNF-α), and then the normal control group was named as TNF-α group, and the P131R group was named as TNF-α+P131R group. Electric cell-substrate impedance sensing (ECIS) assay was used to evaluate the change in the monolayer barrier function of intestinal epithelial cells in the above four groups, and Western blot was used to measure the change in the expression of SLC26A3 protein in the normal control group and the P131R group. RESULTS: The eukaryotic recombinant expression plasmid (pSpCas9-SLC26A3) was successfully constructed. Both Taqman genotyping assay and Sanger sequencing confirmed the successful establishment of the Caco-2 cell model of SLC26A3 c.392C>G (p.P131R) expression. ECIS assay showed that compared with the normal control group, the P131R group had a significant increase in the monolayer permeability of intestinal epithelial cells (P<0.05), and at the same time, the P131R group had a significantly greater increase in cell membrane permeability after the induction with 100 ng/mL TNF-α (P<0.05). Western blot showed that compared with the normal control group, the P131R group had a significant reduction in the expression of SLC26A3 protein (P=0.001). CONCLUSIONS: SLC26A3 c.392C>G (p.P131R) can reduce the expression of SLC26A3 protein, increase the monolayer permeability of intestinal epithelial cells, and thus lead to diarrhea.

Increasing Resistance to Azithromycin in Neisseria gonorrhoeae in Eastern Chinese Cities: Resistance Mechanisms and Genetic Diversity among Isolates from Nanjing.

Azithromycin resistance (AZM-R) of Neisseria gonorrhoeae is emerging as a clinical and public health challenge. We determined molecular characteristics of recent AZM-R Nanjing gonococcal isolates and tracked the emergence of AZM-R isolates in eastern Chinese cities in recent years. A total of 384 N. gonorrhoeae isolates from Nanjing collected from 2013 to 2014 were tested for susceptibility to AZM and six additional antibiotics; all AZM-R strains were characterized genetically for resistance determinants by sequencing and were genotyped using N. gonorrhoeae multiantigen sequence typing (NG-MAST). Among the 384 isolates, 124 (32.3%) were AZM-R. High-level resistance (MIC, ≥256 mg/liter) was present in 10.4% (40/384) of isolates, all of which possessed the A2143G mutation in all four 23S rRNA alleles. Low- to mid-level resistance (MIC, 1 to 64 mg/liter) was present in 21.9% (84/384) of isolates, 59.5% of which possessed the C2599T mutation in all four 23S rRNA alleles. The 124 AZM-R isolates were distributed in 71 different NG-MAST sequence types (STs). ST1866 was the most prevalent type in high-level AZM-R (HL-AZM-R) isolates (45% [18/40]). This study, together with previous reports, revealed that the prevalence of AZM-R in N. gonorrhoeae isolates in certain eastern Chinese cities has risen >4-fold (7% to 32%) from 2008 to 2014. The principal mechanisms of AZM resistance in recent Nanjing isolates were A2143G mutations (high-level resistance) and C2599T mutations (low- to mid-level resistance) in the 23S rRNA alleles. Characterization of NG-MAST STs and phylogenetic analysis indicated the genetic diversity of N. gonorrhoeae in Nanjing; however, ST1866 was the dominant genotype associated with HL-AZM-R isolates.

Engineering T7 bacteriophage as a potential DNA vaccine targeting delivery vector.

BACKGROUND: DNA delivery with bacteriophage by surface-displayed mammalian cell penetrating peptides has been reported. Although, various phages have been used to facilitate DNA transfer by surface displaying the protein transduction domain of human immunodeficiency virus type 1 Tat protein (Tat peptide), no similar study has been conducted using T7 phage. METHODS: In this study, we engineeredT7 phage as a DNA targeting delivery vector to facilitate cellular internalization. We constructed recombinant T7 phages that displayed Tat peptide on their surface and carried eukaryotic expression box (EEB) as a part of their genomes (T7-EEB-Tat). RESULTS: We demonstrated that T7 phage harboring foreign gene insertion had packaged into infective progeny phage particles. Moreover, when mammalian cells that were briefly exposed to T7-EEB-Tat, expressed a significant higher level of the marker gene with the control cells infected with the wide type phage without displaying Tat peptides. CONCLUSION: These data suggested that the potential of T7 phage as an effective delivery vector for DNA vaccine transfer.

Higher exosomal phosphorylated tau and total tau among veterans with combat-related repetitive chronic mild traumatic brain injury.

OBJECTIVE: The objective of the study is to measure plasma and exosomal levels of tau, phosphorylated tau (p-tau), and amyloid beta (Aß) in Veterans with historical mild traumatic brain injury (mTBI) and chronic neuropsychological symptoms. METHODS: Tau, p-tau, Aß40, and Aß42 were measured by ultrasensitive immunoassay in plasma and exosomes from 195 Veterans enrolled in the Chronic Effects of Neurotrauma Consortium Multicenter Observational Study. Protein biomarkers were compared among groups with and without mTBI with loss of consciousness (LOC) or post-traumatic amnesia (PTA), and also in those with and without repetitive (≥3) mTBI (rTBI) compared to those with 0 (TBI-neg) and 1-2 mTBI. RESULTS: There were no differences in measures of plasma and exosomal protein levels among mTBI with LOC or PTA, mTBI with alteration of consciousness only or TBI-neg. Exosomal tau and exosomal p-tau were elevated in rTBI compared to those with 2 or fewer mTBIs and TBI-neg (p < 0.05). Elevations of exosomal tau and p-tau significantly correlated with post-traumatic and post-concussive symptoms, with exosomal tau also relating specifically to cognitive, affective, and somatic post-concussive symptoms (p < 0.05). CONCLUSION: rTBI is associated with elevations of exosomal p-tau and exosomal tau, suggesting that blood-based exosomes may provide a peripheral source of informative, centrally derived biomarkers in remote mTBI and that rTBI may contribute to chronic neuropsychological symptoms.

Localized cortical chronic traumatic encephalopathy pathology after single, severe axonal injury in human brain.

Chronic traumatic encephalopathy (CTE) is a neurodegenerative disease associated with repetitive mild impact traumatic brain injury from contact sports. Recently, a consensus panel defined the pathognomonic lesion for CTE as accumulations of abnormally hyperphosphorylated tau (p-tau) in neurons (neurofibrillary tangles), astrocytes and cell processes distributed around small blood vessels at sulcal depths in irregular patterns within the cortex. The pathophysiological mechanism for this lesion is unknown. Moreover, a subset of CTE cases harbors cortical ß-amyloid plaques. In this study, we analyzed postmortem brain tissues from five institutionalized patients with schizophrenia and history of surgical leucotomy with subsequent survival of at least another 40 years. Because leucotomy involves severing axons bilaterally in prefrontal cortex, this surgical procedure represents a human model of single traumatic brain injury with severe axonal damage and no external impact. We examined cortical tissues at the leucotomy site and at both prefrontal cortex rostral and frontal cortex caudal to the leucotomy site. For comparison, we analyzed brain tissues at equivalent neuroanatomical sites from non-leucotomized patients with schizophrenia, matched in age and gender. All five leucotomy cases revealed severe white matter damage with dense astrogliosis at the axotomy site and also neurofibrillary tangles and p-tau immunoreactive neurites in the overlying gray matter. Four cases displayed p-tau immunoreactivity in neurons, astrocytes and cell processes encompassing blood vessels at cortical sulcal depths in irregular patterns, similar to CTE. The three cases with apolipoprotein E ε4 haplotype showed scattered ß-amyloid plaques in the overlying gray matter, but not the two cases with apolipoprotein E ε3/3 genotype. Brain tissue samples from prefrontal cortex rostral and frontal cortex caudal to the leucotomy site, and all cortical samples from the non-leucotomized patients, showed minimal p-tau and ß-amyloid pathology. These findings suggest that chronic axonal damage contributes to the unique pathology of CTE over time.

[Effect of eicosapentaenoic acid on mRNA expression of tight junction protein ZO-1 in intestinal epithelial cells after Escherichia coli LF82 infection].

OBJECTIVE: To investigate the change in the expression of tight junction protein ZO-1 in intestinal epithelial cells (Caco-2 cells) and the protective effect of eicosapentaenoic acid (EPA) after adherent-invasive Escherichia coli (E.coli) LF82 infection. METHODS: The Caco-2 cell line was used to establish an in vitro model of tight junction of intestinal epithelial cells. Caco-2 cells were divided into EPA treatment groups (0, 25, 50, 100, and 200 µmol/L EPA) and EPA (0, 25, 50, 100, and 200 µmol/L EPA)+E.coli LF82 treatment (0, 6, and 12 hours) groups. A microscope was used to observe the morphological characteristics of the cells. MTT assay was used to determine the cell growth curve. The activity of alkaline phosphatase (ALP) at both sides of the cell membrane was compared to evaluate the Caco-2 cell model. MTT assay and flow cytometry were used to investigate the effects of different concentrations of EPA on the survival rate and apoptosis rate of Caco-2 cells. RT-qPCR was used to measure the mRNA expression of ZO-1 in Caco-2 cells after EPA and/or E.coli LF82 treatment. ELISA was used to measure the change in the level of tumor necrosis factor-α (TNF-α) in culture supernatant. RESULTS: After EPA treatment (25 and 50 µmol/L), the proliferation of Caco-2 cells was induced in a dose-dependent manner. The survival rates of the cells were significantly higher than those in the control group (P<0.05). The EPA treatment (100 and 200 µmol/L) groups had a significant inhibitory effect on the proliferation of Caco-2 cells in a dose-dependent manner. The survival rates of the cells were significantly lower than those in the control group (P<0.05). The EPA treatment (100 and 200 µmol/L) groups had a significant increase in cell apoptosis rate compared with the control group (P<0.05). The 6- and 12-hour E.coli LF82 treatment groups had decreasing mRNA expression of ZO-1 in Caco-2 cells over the time of treatment and had significantly lower mRNA expression of ZO-1 than the untreated group (P<0.05). The Caco-2 cells treated with E.coli LF82 and 25 or 50 µmol/L EPA for 6 or 12 hours showed an increase in the mRNA expression of ZO-1 with the increasing concentration of EPA, as well as significantly higher mRNA expression of ZO-1 than the Caco-2 cells treated with E.coli LF82 alone (P<0.05). The Caco-2 cells treated with E.coli LF82 alone for 6 or 12 hours had increasing secretion of TNF-α over the time of treatment and had significantly higher secretion than the untreated Caco-2 cells (P<0.05). The Caco-2 cells treated with E.coli LF82 and 25 or 50 µmol/L EPA for 6 or 12 hours showed a reduction in the secretion of TNF-α with the increasing concentration of EPA and had significantly lower secretion than the Caco-2 cells treated with E.coli LF82 alone (P<0.05). CONCLUSIONS: EPA can effectively prevent the destruction of tight junction of intestinal epithelial cells induced by E.coli LF82 infection and inhibit the secretion of inflammatory factors. Therefore, it has a certain protective effect on intestinal mucosal barrier.

Multidrug-Resistant Neisseria gonorrhoeae Isolates from Nanjing, China, Are Sensitive to Killing by a Novel DNA Gyrase Inhibitor, ETX0914 (AZD0914).

We tested the activity of ETX0914 against 187 Neisseria gonorrhoeae isolates from men with urethritis in Nanjing, China, in 2013. The MIC50, MIC90, and MIC range for ETX0914 were 0.03 µg/ml, 0.06 µg/ml, and ≤0.002 to 0.125 µg/ml, respectively. All isolates were resistant to ciprofloxacin, and 36.9% (69/187) were resistant to azithromycin. Of the isolates, 46.5% were penicillinase-producing N. gonorrhoeae (PPNG), 36% were tetracycline-resistant N. gonorrhoeae (TRNG), and 13% (24 isolates) had an MIC of 0.125 µg/ml for ceftriaxone. ETX0914 may be an effective treatment option for gonorrhea.

Antimicrobial susceptibility of Neisseria gonorrhoeae isolates from symptomatic men attending the Nanjing sexually transmitted diseases clinic (2011-2012): genetic characteristics of isolates with reduced sensitivity to ceftriaxone.

BACKGROUND: Evolving gonococcal antimicrobial resistance (AMR) poses a serious threat to public health. The aim of this study was to: update antimicrobial susceptibility data of Neisseria gonorrhoeae recently isolated in Nanjing, China and identify specific deteminants of antimicrobial resistance and gentoypes of isolates with decreased sensitivity to ceftriaxone. METHODS: 334 N. gonorrhoeae isolates were collected consecutively from symptomatic men attending the Nanjing STD Clinic between April 2011 and December 2012. The minimum inhibitory concentrations (MICs) for penicillin, tetracycline, ciprofloxacin, spectinomycin and ceftriaxone were determined by agar plate dilution for each isolate. Penicillinase-producing N. gonorrhoeae (PPNG) and tetracycline-resistant N. gonorrhoeae (TRNG) were examined and typed for ß-lactamase and tetM encoding plasmids respectively. Isolates that displayed elevated MICs to ceftriaxone (MIC ≥0.125 mg/L) were also tested for mutations in penA, mtrR, porB1b, ponA and pilQ genes and characterized by Neisseria gonorrhoeae multi-antigen sequence typing (NG-MAST). RESULTS: 98.8% (330/334) of N. gonorrhoeae isolates were resistant to ciprofloxacin; 97.9% (327/334) to tetracycline and 67.7% (226/334) to penicillin. All isolates were susceptible to ceftriaxone (MIC ≤0.25 mg/L) and spectinomycin (MIC ≤32 mg/L). Plasmid mediated resistance was exhibited by 175/334 (52%) of isolates: 120/334 (36%) of isolates were PPNG and 104/334 (31%) were TRNG. 90.0% (108/120) of PPNG isolates carried the Asia type ß-lactamase encoding plasmid and 96% (100/104) of TRNG isolates carried the Dutch type tetM containing plasmid. Elevated MICs for ceftriaxone were present in 15 (4.5%) isolates; multiple mutations were found in penA, mtrR, porB1b and ponA genes. The 15 isolates were distributed into diverse NG-MAST sequence types; four different non-mosaic penA alleles were identified, including one new type. CONCLUSIONS: N. gonorrhoeae isolates in Nanjing generally retained similar antimicrobial resistance patterns to isolates obtained five years ago. Fluctuations in resistance plasmid profiles imply that genetic exchange among gonococcal strains is ongoing and is frequent. Ceftriaxone and spectinomycin remain treatments of choice of gonorrhea in Nanjing, however, decreased susceptibility to ceftriaxone and rising MICs for spectinomycin of N. gonorrhoeae isolates underscore the importance of maintaining surveillance for AMR (both phenotypic and genotypic).