Time-bin phase-encoding quantum key distribution using Sagnac-based optics and compatible electronics.

In this work, we present a new time-bin phase-encoding quantum key distribution (QKD), where the transmitter utilizes an inherently stable Sagnac-type interferometer, and has comparable electrical requirements to existing polarization or phase encoding schemes. This approach does not require intensity calibration and is insensitive to environmental disturbances, making it both flexible and high-performing. We conducted experiments with a compact QKD system to demonstrate the stability and secure key rate performance of the presented scheme. The results show a typical secure key rate of 6.2 kbps@20 dB and 0.4 kbps@30 dB with channel loss emulated by variable optical attenuators. A continuous test of 120-km fiber spool shows a stable quantum bit error rate of the time-bin basis within 0.4%∼0.6% over a consecutive 9-day period without any adjustment. This intrinsically stable and compatible scheme of time-bin phase encoding is extensively applicable in various QKD experiments, including BB84 and measurement-device-independent QKD.

Nitric Oxide Inhibitory Sesquiterpenoids and Its Dimers from Artemisia freyniana.

Two new disesquiterpenoids (1 and 2) and 11 new (3-13) and 10 known (14-23) sesquiterpenoids were isolated from the whole plants of Artemisia freyniana. Their structures were elucidated by spectroscopic data analysis and comparison with published NMR data. The absolute configurations of the new isolates (1-13) were assigned based on single-crystal X-ray diffraction data and comparison of the experimental and calculated ECD data. The eremophilane derivatives 8 and 9 possess an unprecedented 2-isopropyl-3,7,7a-trimethyl-2,4,5,6,7,7a-hexahydro-1 H-indene scaffold, and a putative biosynthetic pathway for these compounds is proposed. Compounds 4, 5, and 9 exhibited inhibitory effects against LPS-stimulated nitric oxide (NO) production in RAW 264.7 macrophage cells with IC50 values of 10.8, 12.6, and 11.7 µM, respectively.

Synthesis of piscidinol A derivatives and their ability to inhibit HIV-1 protease.

Four types of piscidinol A derivatives were synthesized and evaluated their ability to inhibit HIV-1 protease to understand their structure-activity relationships. Of these tirucallane-type triterpene derivatives, an A-seco derivative (1b) moderately inhibited human immunodeficiency virus (HIV) protease (IC50 38.2 µM). The 2,2-dimethyl succinic acid (DMS) acylated tirucallane derivatives (4b, 6a, and 7b, 50 < IC50 < 100 µM) were more inhibitory against HIV-1 PR than the others (PA, 2a, 4a, 4c-4d, 5a, 6b-6d, and 7a, IC50 > 100 µM). These findings indicated that the 2,3-seco-2,3-dioic acid (1b) and DMS-acylated tirucallane-type derivatives preferably inhibited HIV viral protease.

[The Development of Gene Knockout Technologies in Large and Medium Animal Models].

Technique of homologous recombination based gene targeting developed in the late 1980s and won the Nobel Prize in Physiology or Medicine in 2007. However, this technique could only performed in mice which embryonic stem (ES) cells could keep in the potential of multifunction in vitro. Therefore gene knockout technology was difficult to be applied in other species of animals for a long time. Since 2008, with the development of the new technologies, such as the new ES cell gene targeting, zinc finger nucleases (ZFNs), transcription activator-like effector nucleases (TALENs) and clusters of regularly interspaced short palindromic repeats/Cas9 (CRISPR/Cas9), building gene knockout in large and medium animals models which are similar to human in disease research becomes possible. This review describes some new gene knockout technologies in large and medium animal models for recent years.

An analysis and prediction of nucleosome positioning based on information content.

Nucleosome positioning plays a key role in the regulation of many biological processes. In this study, the statistical difference of information content was investigated in nucleosome and linker DNA regions across eukaryotic organisms. By analyzing the information redundancy, D k , in Saccharomyces cerevisiae, Drosophila melanogaster, and Caenorhabditis elegans genomes, the short-range dominance of nucleotide correlation in nucleosome and linker DNA regions was confirmed. Significant difference of the D k value between the nucleosome and linker DNA regions was also found. The underlying reason for many successful oligonucleotide-based predictions of nucleosome positioning in eukaryotic model organisms may be attributed to the short-range dominance of nucleotide correlation in the nucleosome and linker DNA regions. When applying power spectrum analysis to the nucleosome and linker DNA regions, some obvious differences in sequence periodic signals were observed. The parameter F k was introduced to describe particular base correlation. Furthermore, the support vector machine combining F k was used to classify nucleosome and linker DNA regions in Homo sapiens, Oryzias latipes, C. elegans, Candida albicans, and S. cerevisiae. Independent test demonstrated that a good performance can be achieved by using this algorithm. This result further revealed that base correlation information has an important role in nucleosome positioning.

Characterization of a new sesquiterpene and antifungal activities of chemical constituents from Dryopteris fragrans (L.) Schott.

One new sesquiterpene and six known compounds were isolated from Dryopteris fragrans (L.) Schot. They were identified as 3-O-ß-D-glucopyranosylalbicanol- 11-O-ß-D-glucopyranoside (1), dihydroconiferylalcohol (2), (E)-3-(4-hydroxyphenyl)acrylic acid (3), esculetin (4), 5,7-dihydroxy-2-hydroxymethylchromone (5), eriodictyol (6) and isoorientin (7) by UV, MS, 1D-NMR and 2D-NMR spectroscopy. The antifungal activities of the seven isolated compounds were screened. Compounds 2, 3, 4 and 5 showed obvious activities against Microsporum canis and Epidermophyton floccosum.

Two new species and three new records of the genus Aphelocheirus (Hemiptera: Heteroptera: Aphelocheiridae) from China.

Two new species of the genus Aphelocheirus (Hemiptera: Heteroptera: Aphelocheiridae), A. longlingensis sp. nov. from Yunnan and A. motuoensis sp. nov. from Xizang (Tibet) Autonomous Region are described in this paper. A. similaris Polhemus & Polhemus, 1989, A. nawae Nawa, 1905 and A. tuberculipes Zettel & Tran, 2009 are reported from China for the first time. A key to Chinese species of Aphelocheirus is given. Dorsal habitus photographs of the species are provided, accompanied by illustrations of male genitalic structures, inner projection and female ventral aspect of posterior abdominal segments. 

A study on the genus Compsidolon Reuter, 1899 from China (Hemiptera: Heteroptera: Miridae: Phylinae), with descriptions of three new species.

Compsidolon Reuter from China with eleven species is reviewed here. Three of them, C. ailaoshanensis, C. flavidum, and C. pilosum are described as new to science. C. eximium (Reuter) is recorded from China for the first time. Compsidolon punctulatum Qi and Nonnaizab, 1995 is treated as a junior synonym of Compsidolon nebulosum (Reuter, 1878). A key to Chinese species of Compsidolon Reuter is given. Photographs of dorsal habitus, scanning electron micrographs of metathoracic scent-gland, and illustrations of male genitalia are also provided. All type specimens are deposited in the Institute of Entomology, Nankai University, Tianjin, China.

Checklist and distribution of Nepomorpha (Hemiptera: Heteroptera) from China.

An updated catalog of the infraorder Nepomorpha from China is provided based on literature reports, museum specimens, and field collections. In total, 214 species of Nepomorpha are listed in 6 superfamilies, 11 families, and 37 genera, including: Aphelocheiridae (1 genus, 27 species), Belostomatidae (3 genera, 7 species), Corixidae (9 genera, 52 species), Gelastocoridae (1 genus, 3 species), Helotrephidae (5 genera, 25 species), Micronectidae (1 genus, 28 species), Naucoridae (7 genera, 12 species), Nepidae (5 genera, 21 species), Notonectidae (4 genera, 32 species), Ochteridae (1 genus, 2 species) and Pleidae (1 genus, 5 species). Paraplea liturata (Fieber, 1844) is reported from mainland China for the first time. Distribution maps are provided for most species and are based on museum specimens and our field collections.

Effect of short-term nitrogen deposition on dry-wet seasonal variation of soil respiration in degraded Poa pratensis alpine meadow of the Napahai, Yunnan, China.

To explore the coupling of dry-wet seasonal variations of soil respiration with their environmental factors in the alpine meadow under the background of increasing nitrogen (N) deposition, we conducted an experiment in the typical degraded Poa pratensis meadow in the Napahai, Yunnan. There were four treatments, i.e., control (0 g·m-2·a-1), low (5 g·m-2·a-1), medium (10 g·m-2·a-1), and high (15 g·m-2·a-1) levels. We examined the effects of aboveground biomass, plant diversity, and soil physicochemical properties on soil respiration. The results showed that N deposition significantly promoted soil respiration. Compared with that in the control, soil respiration rates increased by 21.9%-53.9% and 27.3%-51.2% in dry and wet seasons, respectively. The maximum value of soil respiration rate was recorded in the medium N treatment. N deposition dramatically elevated aboveground biomass (52.2%-66.4%). Plant diversity declined with increasing N addition levels, with the maximum value (13.5%-24.2%) being recorded in high treatment in wet season. The values of ammonium nitrogen, organic matter, microbial biomass carbon and nitrogen, temperature and moisture in the three N treatments were elevated by 14.3%-333.5% compared with the control, while those of soil pH were decreased by 9.0%-34.6%. Results of the structural equation modelling showed that plant biomass, Shannon diversity, microbial biomass, soil temperature, and moisture showed a positive effect on soil respiration, while bulk density had a negative effect. Soil nitrogen pool and pH were main factors driving soil CO2 emissions, accounting for 55.7% and 45.1% of the variations, respectively. Therefore, short-term atmospheric N deposition stimulated soil respiration primarily via altering soil pH and nitrogen pool components in the degraded alpine meadow.

Cellular mechanism underlying leptin-induced anion secretion of rat epididymal epithelial cells.

BACKGROUND: A large number of studies have shown that leptin plays an important role in the regulation of fertility via the hypothalamus-pituitary-gonad axis. However, its peripheral function in epididymis was still elusive. OBJECTIVE: The purpose of this study was to determine the pro-secretion effect of leptin on the rat epididymal epithelium. MATERIALS AND METHODS: In the present study, real-time quantitative polymerase chain reaction, western blot, and immunohistochemical analysis were employed to detect the expression pattern of leptin receptors in rat epididymis. The pro-secretion effect of leptin on epididymal epithelial cells was measured by short-circuit current, and the prostaglandin E2 and cyclic adenosine monophosphate level was evaluated by enzyme-linked immunosorbent assay. RESULTS: We verified that the leptin receptor was located on the epididymal epithelium, with a relatively high expression level in corpus and cauda epididymis. Ussing chamber experiments showed that leptin stimulated a significant rise of the short-circuit current in rat epididymal epithelial cells, which could be abolished by the specific leptin receptor antagonist peptide Allo-aca, or by removing the ambient Cl- and HCO3 -. Furthermore, the leptin-stimulated short-circuit current response could be abrogated by blocking the apical cystic fibrosis transmembrane regulator or the basolateral Na+-K+-2Cl- cotransporter. Our pharmacological experiments manifested that interfering with the prostaglandin H synthase-2-prostaglandin E2-EP2/EP4-adenylate cyclase pathways could significantly blunt the cystic fibrosis transmembrane regulator-mediated anion secretion induced by leptin. The enzyme-linked immunosorbent assay demonstrated that leptin could induce a substantial increase in prostaglandin E2 release and cyclic adenosine monophosphate synthesis of primary cultured rat cauda epididymal epithelial cells. Our data also suggested that JAK2, ERK, and PI3K-dependent phosphorylation may be involved in the activation of prostaglandin H synthase-2 and the subsequent prostaglandin E2 production. CONCLUSIONS: The present study demonstrated the pro-secretion function of leptin in rat epididymal epithelium via the activation of cystic fibrosis transmembrane regulator and Na+-K+-2Cl- cotransporter, which was dependent on the paracrine/autocrine prostaglandin E2 stimulated EP2/EP4-adenylate cyclase pathways, and thus contributed to the formation of an appropriate microenvironment essential for sperm maturation.

Correlation of inflammatory cells in adventitia and formation and extending of atherosclerotic lesions in coronary artery of apolipoprotein E gene knockout mice.

Accumulating evidence shows that adventitial inflammation contributes to the development of atherosclerotic lesions. The aim of this study was to investigate the relationship between atherosclerotic lesions in coronary artery (CA) and accumulation of inflammatory cells at local adventitia in apolipoprotein E gene knockout (apoE-/-) mice. Modified Movat's pentachrome staining, HE staining, immunohistochemistry and transmission electron microscopy were used to observe and to identify serial paraffin sections of aortic foot and inflammatory cells in CA adventitia of apoE-/- mice of 60 weeks old. There was always accumulation of inflammatory cells in the adventitia of CA with extending lesions from aortic orifice to CA trunks. The CA samples were divided into type I: infiltration of inflammatory cells in CA adventitia without lesions extending in the intima, type II: infiltration of inflammatory cells in CA adventitia with the top of extending lesions in the intima and type III: infiltration of inflammatory cells at CA adventitia with lesions covering all the face of intima. The three types of CA sample represent the different developmental processes of atherosclerotic lesions, respectively. No extending lesions were found in the CA trunks without inflammatory cells in adventitia. In type I samples, 60% of infiltrated inflammatory cells were macrophages 57% of infiltrated cells were neutrophils in type II samples; 67% of infiltrated cells were lymphocytes in type III samples. Our studies revealed that adventitial inflammation may be an early event in the development of atherosclerotic lesions. Different cell types predominate in different stages of CA adventitia. The neutrophils are closely related to the extending of atherosclerotic lesions.

[Myocardial expression of Spry1 and MAPK proteins of viral myocarditis].

OBJECTIVE: To discuss the myocardial expression of Spry1 and MAPK proteins of viral myocarditis (VMC), to reveal its mechanism of sudden death, and to provide guides for forensic identification of sudden cardiac death. METHODS: Thirty Balb/c male mice were randomly divided into VMC group and control group, inoculated intraperitoneally with Coxsackievirus B3 and Eagel's solution, respectively. After the mice were sacrificed, the cardiac tissues of the mice were taken to proceed regular pathological examination. The changes of Spry1 protein, Spry1 mRNA and MAPK protein were detected by immunohistochemistry, Western blotting and real-time PCR. RESULTS: Under light microscope, the pathologic changes included myocardial interstitial edema, inflammatory cells infiltration, myocardial necrosis, and focal and patchy necrosis of myocardial fiber in VMC group. The expression of Spry1 protein in VMC group was lower than that in control group (P < 0.05). There was slightly decreased expression of Spry1 of the mRNA level in VMC group (P > 0.05). But the MAPK protein expression in VMC group was higher than that in control group (P < 0.05). CONCLUSION: The pathway of MAPK/ERK involving Spry1 protein accelerates the expression of collagen, which may contribute to arrhythmia, heart failure and even sudden cardiac death.

Case report: 177Lu DOTA-TATE: a new scheme for the treatment of prostate neuroendocrine cancer.

Background: Most instances of small cell carcinoma originate from the lungs, while the gastrointestinal tract serves as a secondary site. Only a minuscule proportion of cases manifest within the urogenital system. Prostate small cell carcinoma (SCCP) represents an exceedingly uncommon pathological subtype within the realm of prostate cancer, displaying significant rarity in clinical settings. This scarcity has resulted in a paucity of adequate foundational and clinical research for SCCP treatment. While investigations have unveiled a certain therapeutic efficacy of radiotherapy and chemotherapy for SCCP, clinical practice has revealed suboptimal treatment outcomes. We hereby present a case report detailing the utilization of 177Lu-DOTA-TATE in the treatment of SCCP, aiming to investigate the therapeutic efficacy of 177Lu-DOTA-TATE for SCCP. Case presentation: A male patient in his 80s presented with elevated prostate-specific antigen (PSA) levels and underwent a biopsy that revealed prostate adenocarcinoma. The patient received CAB (bicalutamide + goserelin) therapy. One year later, disease progression was detected, and a second biopsy confirmed the presence of prostate small cell carcinoma. Following the diagnosis of prostate small cell carcinoma, the patient underwent two cycles of 177Lu-DOTA-TATE treatment. Subsequent to the treatment, the original lesions showed shrinkage, metastatic lesions disappeared, and there was significant improvement, approaching complete remission. Conclusion: SCCP exhibits a high degree of malignancy and aggressive invasiveness, currently lacking effective therapeutic modalities. The treatment course of this patient serves as compelling evidence for the efficacy of 177Lu-DOTA-TATE in managing SCCP, thereby opening new avenues for future SCCP treatments.

CYP1B1 Leu432Val polymorphism and colorectal cancer risk among Caucasians: a meta-analysis.

Studies investigating the association between cytochrome P450 1B1 (CYP1B1) Leu432Val (432 C/G, rs1056836) polymorphism and colorectal cancer (CRC) risk report conflicting results. The aim of this study was to quantitatively summarize the evidence for such a relationship. Two investigators independently searched the Medline, Embase, China National Knowledge Infrastructure, and Chinese Biomedicine Databases. Summary odds ratios (ORs) and 95% confidence intervals (95% CIs) for CYP1B1 polymorphism and CRC were calculated in a fixed-effects model and a random-effects model when appropriate. The pooled ORs were performed for co-dominant model (GG vs. CC, GC vs. CC), dominant model (GG + GC vs. CC), and recessive model (GG vs. GC + CC). This meta-analysis included ten case-control studies, which included 8,466 CRC cases and 9,301 controls. Overall, the variant genotypes (GG and GC) of the 432 C/G were not associated with CRC risk when compared with the wild-type CC homozygote (GG vs. CC, OR = 1.01, 95% CI = 0.93-1.10; GC vs. CC, OR = 0.97, 95% CI = 0.90-1.04), without any between-study heterogeneity. Similarly, no associations were found in the dominant and recessive models (dominant model, OR = 0.98, 95% CI = 0.92-1.05; recessive model, OR = 1.03, 95% CI = 0.96-1.11). Limiting the analysis to the studies within Hardy-Weinberg equilibrium, the results were persistent and robust. When stratifying for country, matched control and source of controls, no evidence of significant association was observed in any subgroup. No publication bias was found in the present study. No association is found between the CYP1B1 Leu432Val polymorphism and risk of CRC among Caucasians.

Hypertriglyceridemia: A Neglected Risk Factor for Ischemic Stroke?

Hypertriglyceridemia is caused by defects in triglyceride metabolism and generally manifests as abnormally high plasma triglyceride levels. Although the role of hypertriglyceridemia may not draw as much attention as that of plasma cholesterol in stroke, plasma triglycerides, especially nonfasting triglycerides, are thought to be correlated with the risk of ischemic stroke. Hypertriglyceridemia may increase the risk of ischemic stroke by promoting atherosclerosis and thrombosis and increasing blood viscosity. Moreover, hypertriglyceridemia may have some protective effects in patients who have already suffered a stroke via unclear mechanisms. Therefore, further studies are needed to elucidate the role of hypertriglyceridemia in the development and prognosis of ischemic stroke.

In Situ Constructing a Catalytic Shell for Sulfur Cathode via Electrochemical Oxidative Polymerization.

Sluggish multiphase reaction kinetics and severe shuttle effect of lithium polysulfides (LiPSs) are two major challenges facing lithium-sulfur (Li-S) batteries, which largely prevent them from becoming a reality. Herein, a shell with catalytic function for sulfur cathode is in situ constructed through an ingenious electrochemical oxidative polymerization strategy by introducing hexafluorocyclotriphosphazene (HFPN) as additives, which suppresses the shuttle effect and promotes efficient sulfur conversion. The shell with abundant heteroatoms effectively confines polysulfides to the cathode matrix by chemically interacting with them to eliminate capacity degradation. Moreover, the shell exhibits high catalytic activities, which turns Li2S(2) into an activated state and facilitates its dissociation. The functionalized shell substantially advances the performance of Li-S batteries, thanks to efficient lithium-ion transportation and abundant adsorption-catalytic sites. As a result, Li-S batteries demonstrate superb resistance to self-discharge, ultrastable cycle performance, and greatly enhanced rate capability. Impressively, the batteries show an ultralow capacity decay rate of 0.034% throughout 700 cycles at 2C. They deliver a capacity of 517 mAh g-1 even at a 4C rate, exhibiting relieved electrochemical polarization and excellent sulfur utilization. This work provides an ingenious strategy to construct adsorption-catalytic nets for next-generation Li-S batteries with enhanced lifespan and electrochemical performance.

Combinatorial patterns of histone modifications in Saccharomyces cerevisiae.

Histone modification is an important subject of epigenetics that plays an intrinsic role in transcriptional regulation. It has been suggested that multiple histone modifications act in a combinatorial fashion to form a 'histone code'. In this study, the combinatorial patterns of histone modifications were studied by using a Bayesian network at the level of individual nucleosomes in S. cerevisiae. Our results indicated that there were 23 combinatorial patterns for 12 histone modifications investigated when a general Bayesian network was constructed. Meanwhile, different networks were also constructed for the genes with high transcript levels (H-network) and low transcript levels (L-network), respectively. Comparison among the general network, H-network and L-network illustrated four conserved combinations: H2BK16Ac → H3K4me3; H3K14Ac → H3K4me3; H2AK7Ac → H3K14Ac; and H4K12Ac → H3K18Ac. The detailed analysis for some combinations demonstrated that the combinations were ascribed to some histone-modifying enzymes.

Reversal of multidrug resistance by guggulsterone in drug-resistant MCF-7 cell lines.

BACKGROUND: Multidrug resistance (MDR) presents a serious problem in cancer chemotherapy. Our previous studies have shown that the MDR of K562/DOX cells could be reversed by guggulsterone through inhibiting the function and expression of P-glycoprotein. The purpose of this study was to investigate the reversal effect of guggulsterone on MDR in drug-resistant MCF-7 cells and the parental MCF-7 cells. METHODS: MTT cytotoxicity assays, flow cytometry, and Western blot analysis were performed to investigate the antiproliferative effects of the combination of anticancer drugs with guggulsterone, to study the reversal of drug resistance and to examine the inhibitory effects on MRP1 expression. RESULTS: The results showed that co-administration of guggulsterone (10 µM) resulted in a significant increase in chemosensitivity of MCF-7/DOX cells to doxorubicin, compared with doxorubicin treatment alone (p < 0.01). The fold reversal of 10 µM guggulsterone (11.48) was comparable to that of 10 µM verapamil (13.23). Rhodamine123 and doxorubicin accumulation in MCF-7/DOX cells was significantly enhanced after the incubation with guggulsterone (10 µM), compared with untreated MCF-7/DOX cells (p < 0.01). When doxorubicin (10 µM) was combined with guggulsterone (10 µM), the mean apoptotic population of MCF-7/DOX cells was 24.91%. It was increased by 6.15 times, compared with doxorubicin (10 µM) treatment alone. However, guggulsterone had little inhibitory effect on the expression of MRP1 proteins. CONCLUSION: Guggulsterone is a novel and potent MDR reversal agent with the potential to be an adjunctive agent for tumor chemotherapy.

A new species of the genus Cenocorixa (Hemiptera, Heteroptera, Corixidae) from China.

A new species of the genus Cenocorixa Hungerford (Hemiptera, Heteroptera, Corixidae) is described from China. Cenocorixayuanjiangensis sp. nov. is reported from Yunnan Province. An updated key to the Chinese species of Cenocorixa is presented.