Advanced Bacterial Cellulose Ionic Conductors with Gigantic Thermopower for Low-Grade Heat Harvesting.

Ionic conductors such as polymer electrolytes and ionic liquids have high thermoelectric voltages several orders of magnitude higher than electronic thermoelectric materials, while their conductivity is much lower than the latter. This work reports a novel approach to achieve high-performance ionic conductors using calcium ion (Ca2+) coordinated bacterial cellulose (CaBC) through molecular channel engineering. Through the coordination of Ca2+ with cellulose molecular chain, the distance between the cellulose molecular chains is widened, so that ions can transport along the cellulose molecular chain. Therefore, we reported ionic thermoelectric (i-TE) material based on CaBC/NaCl with a relatively high ionic Seebeck coefficient of -27.2 mV K-1 and high ionic conductivity of 204.2 mS cm-1. This ionic hydrogel is promising in the design of high-thermopower i-TE materials for low-grade heat energy harvesting.

A novel H129-based anterograde monosynaptic tracer exhibits features of strong labeling intensity, high tracing efficiency, and reduced retrograde labeling.

BACKGROUND: Viral tracers are important tools for mapping brain connectomes. The feature of predominant anterograde transneuronal transmission offers herpes simplex virus-1 (HSV-1) strain H129 (HSV1-H129) as a promising candidate to be developed as anterograde viral tracers. In our earlier studies, we developed H129-derived anterograde polysynaptic tracers and TK deficient (H129-dTK) monosynaptic tracers. However, their broad application is limited by some intrinsic drawbacks of the H129-dTK tracers, such as low labeling intensity due to TK deficiency and potential retrograde labeling caused by axon terminal invasion. The glycoprotein K (gK) of HSV-1 plays important roles in virus entry, egress, and virus-induced cell fusion. Its deficiency severely disables virus egress and spread, while only slightly limits viral genome replication and expression of viral proteins. Therefore, we created a novel H129-derived anterograde monosynaptic tracer (H129-dgK) by targeting gK, which overcomes the limitations of H129-dTK. METHODS: Using our established platform and pipeline for developing viral tracers, we generated a novel tracer by deleting the gK gene from the H129-G4. The gK-deleted virus (H129-dgK-G4) was reconstituted and propagated in the Vero cell expressing wildtype H129 gK (gKwt) or the mutant gK (gKmut, A40V, C82S, M223I, L224V, V309M), respectively. Then the obtained viral tracers of gKmut pseudotyped and gKwt coated H129-dgK-G4 were tested in vitro and in vivo to characterize their tracing properties. RESULTS: H129-dgK-G4 expresses high levels of fluorescent proteins, eliminating the requirement of immunostaining for imaging detection. Compared to the TK deficient monosynaptic tracer H129-dTK-G4, H129-dgK-G4 labeled neurons with 1.76-fold stronger fluorescence intensity, and visualized 2.00-fold more postsynaptic neurons in the downstream brain regions. gKmut pseudotyping leads to a 77% decrease in retrograde labeling by reducing axon terminal invasion, and thus dramatically improves the anterograde-specific tracing of H129-dgK-G4. In addition, assisted by the AAV helper trans-complementarily expressing gKwt, H129-dgK-G4 allows for mapping monosynaptic connections and quantifying the circuit connectivity difference in the Alzheimer's disease and control mouse brains. CONCLUSIONS: gKmut pseudotyped H129-dgK-G4, a novel anterograde monosynaptic tracer, overcomes the limitations of H129-dTK tracers, and demonstrates desirable features of strong labeling intensity, high tracing efficiency, and improved anterograde specificity.

High-density genetic linkage mapping reveals low stability of QTLs across environments for economic traits in Eucalyptus.

Introduction: Eucalyptus urophylla, E. tereticornis and their hybrids are the most important commercial forest tree species in South China where they are grown for pulpwood and solid wood production. Construction of a fine-scale genetic linkage map and detecting quantitative trait loci (QTL) for economically important traits linked to these end-uses will facilitate identification of the main candidate genes and elucidate the regulatory mechanisms. Method: A high-density consensus map (a total of 2754 SNPs with 1359.18 cM) was constructed using genotyping by sequencing (GBS) on clonal progenies of E. urophylla × tereticornis hybrids. QTL mapping of growth and wood property traits were conducted in three common garden experiments, resulting in a total of 108 QTLs. A total of 1052 candidate genes were screened by the efficient combination of QTL mapping and transcriptome analysis. Results: Only ten QTLs were found to be stable across two environments, and only one (qSG10Stable mapped on chromosome 10, and associated with lignin syringyl-to-guaiacyl ratio) was stable across all three environments. Compared to other QTLs, qSG10Stable explained a very high level of phenotypic variation (18.4-23.6%), perhaps suggesting that QTLs with strong effects may be more stably inherited across multiple environments. Screened candidate genes were associated with some transcription factor families, such as TALE, which play an important role in the secondary growth of plant cell walls and the regulation of wood formation. Discussion: While QTLs such as qSG10Stable, found to be stable across three sites, appear to be comparatively uncommon, their identification is likely to be a key to practical QTL-based breeding. Further research involving clonally-replicated populations, deployed across multiple target planting sites, will be required to further elucidate QTL-by-environment interactions.

Shank3 contributes to neuropathic pain by facilitating the SNI-dependent increase of HCN2 and the expression of PSD95.

Neuropathic pain is a very complex chronic pain state, the detailed molecular mechanisms of which remain unclear. In the present study, Shank3 was found to play an important role in neuropathic pain in rats following spared nerve injury (SNI). Shank3 was upregulated in the spinal dorsal horn of rats subjected to SNI, and mechanical hypersensitivity to noxious stimuli in these rats could be alleviated by knock down of Shank3. Shank3 also interacted with hyperpolarization-activated cyclic nucleotide-gated channel 2 (HCN2) and promoted the expression of HCN2 in central neurons of the spinal dorsal. Together with the SNI-dependent increase of HCN2, we also found that the postsynaptic protein of excitatory synapse (PSD95) was increased in rats following SNI. Taken together, our results showed that Shank3 modulated neuropathic pain by facilitating the SNI-dependent increase of HCN2 and the expression of PSD95 in spinal dorsal horn neurons. Our findings revealed new synaptic remodeling mechanisms linking Shank3 with neuropathic pain.

Virus Injection to the Pituitary via Transsphenoidal Approach and the Innervation of Anterior and Posterior Pituitary of Rat.

The theory holds that the anterior pituitary in mammals receives humoral regulation. Previous studies have reported that the pars distalis of the anterior pituitary of several mammalian species contains substance P-, calcitonin gene-related peptide (CGRP)-, and galanin-like immunoreactive nerve fibers, but the origins of these nerve fibers are unclear. Removal of the pituitary gland, also called hypophysectomy, involves methods that access the pituitary gland via the transauricular or parapharyngeal pathways. However, these methods are not applicable for viral tracer injection to investigate the innervation of the anterior pituitary. The transauricular technique leads to inaccuracies in locating the pituitary gland, while the parapharyngeal approach causes high mortality in animals. Here, we introduce a protocol that accesses the pituitary gland in the rat via the transsphenoidal pathway. This method imitates surgical manipulations such as endotracheal intubation and sphenoid bone drilling, which involve the use of custom-made devices. Using the transsphenoidal pathway greatly improves the survival rate of rats because no additional dissection of blood vessels and nerves is required. Moreover, the pituitary gland can be viewed clearly and directly during the operation, making it possible to accurately inject pseudorabies virus (PRV) 152-expressing enhanced green fluorescent protein (EGFP) into the anterior or posterior pituitary, respectively. After injecting PRV 152 into the anterior pituitary, we found no evidence of direct innervation of the anterior pituitary in the rat brain. However, PRV 152 injection into the posterior pituitary revealed retrograde transneuronal cell bodies in many brain areas, including the CA1 field of the hippocampus, the basolateral amygdaloid nucleus, posterior part (BLP), the arcuate hypothalamic nucleus (Arc), the dorsal portion of the dorsomedial hypothalamic nucleus (DMD), the suprachiasmatic nucleus (SCh), and the subfornical organ (SFO). In the present study, we provide a description of a possible model of hypophysectomy or pituitary injection, and identify brain regions involved in regulating the rat pituitary gland using transneuronal retrograde cell body labeling with PRV.

Visualization of gene therapy with a liver cancer-targeted adeno-associated virus 3 vector.

Background: To evaluate the feasibility of a self-complementing recombinant adeno-associated virus 3 (scrAAV3) vector targeting liver cancer and non-invasively monitor gene therapy of liver cancer. Materials and methods: An scrAAV3-HSV1-TK-kallistatin (ATK) gene drug was constructed, which contained the herpes virus thymidine kinase (HSV1-TK) reporter gene and human endogenous angiogenesis inhibitor (kallistatin) gene for non-invasive imaging of gene expression. Subcutaneous xenografted tumors of hepatoma in nude mice were generated for positron emission tomography/computed tomography (PET/CT) imaging. The ATK group was injected with the ATK gene through the tail vein, and an imaging agent was injected 2 weeks later. PET/CT imaging was performed at 1 hour after injection of the imaging agent. The control group was injected with phosphate-buffered saline at the same volume as the ATK gene drug. HE staining is used for pathological observation of tumor sections. HSV1-TK and kallistatin expression was identified by immunofluorescence, real-time quantitative PCR, and western blotting. Results: Radioactivity on PET/CT images was significantly higher in the ATK group compared with the control group. 18F-FHBG uptake values of left forelegs in ATK and control groups were 0.591±0.151% and 0.017 ± 0.011% ID/g (n=5), respectively (P<0.05). After injection of the ATK gene drug, mRNA and protein expression of HSV1-TK and kallistatin in subcutaneous xenograft tumors was detected successfully. In vitro analysis demonstrated significant differences in the expression of HSV1-TK and kallistatin between ATK and control groups (P<0.05). Conclusions: The scrAAV3 vector has a strong liver cancer-targeting ability, and the ATK gene drug can be used for targeted and non-invasive monitoring of liver cancer gene therapy.

[Unconstrained detection of ballistocardiogram and heart rate based on vibration acceleration].

The requirement for unconstrained monitoring of heartbeat during sleep is increasing, but the current detection devices can not meet the requirements of convenience and accuracy. This study designed an unconstrained ballistocardiogram (BCG) detection system using acceleration sensor and developed a heart rate extraction algorithm. BCG is a directional signal which is stronger and less affected by respiratory movements along spine direction than in other directions. In order to measure the BCG signal along spine direction during sleep, a 3-axis acceleration sensor was fixed on the bed to collect the vibration signals caused by heartbeat. An approximate frequency range was firstly assumed by frequency analysis to the BCG signals and segmental filtering was conducted to the original vibration signals within the frequency range. Secondly, to identify the true BCG waveform, the accurate frequency band was obtained by comparison with the theoretical waveform. The J waves were detected by BCG energy waveform and an adaptive threshold method was proposed to extract heart rates by using the information of both amplitude and period. The accuracy and robustness of the BCG detection system proposed and the algorithm developed in this study were confirmed by comparison with electrocardiogram (ECG). The test results of 30 subjects showed a high average accuracy of 99.21% to demonstrate the feasibility of the unconstrained BCG detection method based on vibration acceleration.

Interpreting the Raman OH/OD stretch band of ice from isotopic substitution and phase transition effects.

Understanding the OD/OH stretch band (ODSB/OHSB) features for the Raman spectra of ice remains a challenge. This study measures the ODSB/OHSB for isotopically substituted D2O/H2O (with volume ratio VD2O/VH2O of 1/0, 4/1, 1/1, 1/4 and 0/1) ice Ih, and compares them with those for liquid water and ices in various phases. The data show that istopic substitution (IS) narrows the ODSB/OHSB of ice from both the low-frequency and the high-frequency side to the middle of the OD/OH stretch regions, but in contrast, IS enhances the high-frequency part of the ODSB/OHSB for liquid water. The ODSB/OHSB features of ice and their dependences on IS and phase transition can be understood basically from the concept that ice has diverse HB configurations that depend on the ice lattice form and the proton (dis)order and essentially determine the intermolecular vibrational couplings in ice. Combined with a Gaussian fitting analysis, more details for the HB configurations in ice are revealed: tetrahedral HB profiles, which are responsible for the main peak, are dominant and non-tetrahedral ones, which bring about the high-frequency shoulders, are also important. On IS, the proportion of tetrahedral HB profiles sees a dramatic decrease.

Understanding water structure from Raman spectra of isotopic substitution H2O/D2O up to 573 K.

The OH/OD stretch band on Raman spectra of water is complex, and understanding the spectral features based on water structure needs further study. This study investigates Raman spectra of isotopic substitution (IS) of water (with volume ratio VH2O/VD2O of 0/1, 1/4, 1/1, 4/1 and 1/0) at temperatures from 303 to 573 K. The data show that the OH and OD stretch band profiles are similar in their dependences on temperature and IS ratio. IS reduces the band widths at low temperatures but the reducing effect diminishes above ∼450 K, due to the largely enhanced intensity of the high-frequency shoulder (∼3650 cm-1/2690 cm-1), which turns into the main peak for the OH (or OD) stretch bands when VH2O/VD2O (or VD2O/VH2O) reaches 1/4 at temperatures over ∼510 K. These spectral features strongly indicate a multi-structure model stating that water has various local hydrogen bonding (HB) environments. Intermolecular vibrational couplings are important in determining the band width, while intramolecular vibrational couplings are not recommended for interpreting the OH/OD stretch band. Five dominant HB configurations are identified in water: two types of tetrahedral, single donor (SD) HB configuration, single hydrogen-bonded water (SHW), and free water (FW) without any hydrogen bonds, which are represented by five sub-bands. It is estimated that most (>50%) of the water molecules are in highly asymmetric HB environments (SD and SHW). The increase of temperature breaks HB structure and IS further promotes structure transition from tetrahedral to SD, SHW and FW. Then, number of hydrogen bonds in water are greatly reduced by temperature and IS.

Recombinant protein transduction domain-Cu/Zn superoxide dismutase alleviates bone cancer pain via peroxiredoxin 4 modulation and antioxidation.

Bone cancer pain (BCP) is a serious chronic clinical condition and reactive oxygen species (ROS) were considered to be involved in its development and persistency. Normally, superoxide dismutase (SOD) converts superoxide anions to hydrogen peroxide (H2O2) and H2O2 is then naturalized to be water by peroxiredoxin 4. We reported previously that recombinant protein transduction domain (PTD)-Cu/Zn SOD effectively scavenged excessive ROS and prevented cardiomyocytes from hypoxia-reoxygenation damage. However, whether PTD-Cu/Zn SOD would prevent BCP development is unknown. In the current study, we found that an implanted carcinoma in the rat tibia induced remarkable hyperalgesia, increased H2O2 levels and decreased SOD and peroxiredoxin 4 levels. After administration of recombinant PTD-Cu/Zn SOD to these tumor-burden rats, their hyperalgesia was significantly attenuated and peroxiredoxin 4 expression was significantly increased. In addition, an increased expression of N-methyl-d-aspartic acid (NMDA) receptors and a decreased expression of γ-aminobutyric acid (GABA) receptors in this cancer pain were prevented by PTD-Cu/Zn SOD administration or peroxiredoxin 4 overexpression. Our data suggested that reactive oxygen species, at least in part, play a role in cancer metastatic pain development and persistency which can be attenuated by the adminstration of recombinant PTD-Cu/Zn SOD via the peroxiredoxin 4 modulation from oxidative stress.

Attosecond chirp effect on the transient absorption spectrum of laser-dressed helium atom.

We theoretically investigate the attosecond transient absorption spectrum of helium atom in the presence of an infrared-dressed laser pulse upon scanning their relative delay, with the particular emphasis on the chirp effect of the attosecond pulse. By numerically solving the fully three-dimensional time-dependent Schrödinger equation, we identify the attoscecond chirp can induce the temporal shift of the absorption spectrogram along the delay axis. Additionally, it is found that the extent of the temporal shift is dependent on both the position of the absorption line and the infrared pulse wavelength, which is well confirmed and reproduced by a three-level model. Moreover, we demonstrate that the observed features can be quantitatively explained in terms of the indirect two-photon absorption processes through some virtual states. This effect might provide a way to measure the chirp of attosecond pulse in an all-optical way.

Assessing plasma levels of selenium, copper, iron and zinc in patients of Parkinson's disease.

Trace elements have been recognized to play an important role in the development of Parkinson's disease (PD). However, it is difficult to precisely identify the relationship between these elements and the progression of PD because of an insufficient number of patients. In this study, quantifications of selenium (Se), copper (Cu), iron (Fe) and zinc (Zn) by atomic absorption spectrophotometry were performed in plasma from 238 PD patients and 302 controls recruited from eastern China, which is so far the largest cohort of PD patients and controls for measuring plasma levels of these elements. We found that plasma Se and Fe concentrations were significantly increased whereas Cu and Zn concentrations decreased in PD patients as compared with controls. Meanwhile, these four elements displayed differential changes with regard to age. Linear and logistic regression analyses revealed that both Fe and Zn were negatively correlated with age in PD patients. Association analysis suggests that lower plasma Se and Fe levels may reduce the risk for PD, whereas lower plasma Zn is probably a PD risk factor. Finally, a model was generated to predict PD patients based on the plasma concentrations of these four trace elements as well as other features such as sex and age, which achieved an accuracy of 80.97±1.34% using 10-fold cross-validation. In summary, our data provide new insights into the roles of Se, Cu, Fe and Zn in PD progression.