Generalized modulation for distance-aware optical camera communication beyond oversampled and undersampled schemes.

Oversampled modulation (OM) and undersampled modulation (UM) are two commonly used optical camera communication (OCC) modulation schemes for high-speed communication in short-range and reliable communication at long distances, respectively. However, the relationship between these two schemes and the tradeoff in performance for arbitrary communication distances have not been thoroughly investigated. In this study, we analyze the impact of distance and modulation parameters on pixel efficiency and packet delivery rate performance, demonstrating the underlying unity of traditional OM and UM schemes. Furthermore, we propose a generalized modulation scheme that allows for achieving predefined link performance at a given distance by adjusting the modulation parameters, such as packet length and repetition counts. Simulation and experimental results show that the proposed generalized modulation scheme provides OCC with a unique distance-aware capability other than the traditional OM and UM schemes, which are two special cases focusing on effectiveness and reliability, respectively. This research enhances our understanding of OCC data modulation and establishes a theoretical foundation for achieving efficient and reliable OCC transmission in complex environments.

Identification of potential PIM-2 inhibitors via ligand-based generative models, molecular docking and molecular dynamics simulations.

Proviral Integrations of Moloney-2 (PIM-2) kinase is a promising target for various cancers and other diseases, and its inhibitors hold potential for treating related diseases. However, there is currently no clinically available PIM-2 inhibitor. In this study, we constructed a generative model for de novo PIM-2 inhibitor design based on artificial intelligence, performed molecular docking and molecular dynamics (MD) simulations to develop an efficient PIM-2 inhibitor generative model and discover potential PIM-2 inhibitors. First, we designed a generative model based on a Bi-directional Long Short-Term Memory (BiLSTM) framework combined with a transfer learning strategy and generated a new PIM-2 small molecule library using existing active drug databases. The generated compound library was then virtually screened by molecular docking and scaffold similarity comparison, identifying 10 initial hit compounds with better performance. Next, using the inhibitor in the crystal structure as a positive control, we performed two rounds of MD simulations, with lengths of 100 ns and 500 ns, respectively, to study the dynamic stability of the protein-ligand systems of the 10 compounds with PIM-2. Analyzed the interactions with key hinge region residues, binding free energies, and changes in the ATP pocket size. The generative model demonstrates good molecular generation capability and can generate efficient novel molecules with similar physicochemical properties as active PIM-2 drugs. Among the 10 initially selected hit compounds, 5 compounds C3 (- 29.69 kcal/mol), C4 (- 33.31 kcal/mol), C5 (- 28.59 kcal/mol), C8 (- 34.68 kcal/mol), and C9 (- 25.88 kcal/mol) have higher binding energies with PIM-2 than the positive drug 3YR (- 26.18 kcal/mol). The MD simulation results are consistent with the docking analysis, these compounds have lower and more stable RMSD values for the complex systems with the reported positive drug 3YR and PIM-2 complex system. They can form long-term stable interactions with active site and the hinge region of PIM-2, which suggests these compounds are likely to have potent inhibitory effects on PIM-2. This study provides an efficient generative model for PIM-2 inhibitor research and discovers 5 potential novel PIM-2 inhibitors.

Design, synthesis, and evaluation of cyclic C7-bridged monocarbonyl curcumin analogs containing an o-methoxy phenyl group as potential agents against gastric cancer.

The structure-activity relationship (SAR) between toxicity and the types of linking ketones of C7 bridged monocarbonyl curcumin analogs (MCAs) was not clear yet. In the pursuit of effective and less cytotoxic chemotherapeutics, we conducted a SAR analysis using various diketene skeletons of C7-bridged MCAs, synthesized cyclic C7-bridged MCAs containing the identified low-toxicity cyclopentanone scaffold and an o-methoxy phenyl group, and assessed their anti-gastric cancer activity and safety profile. Most compounds exhibited potent cytotoxic activities against gastric cancer cells. We developed a quantitative structure-activity relationship model (R2 > 0.82) by random Forest method, providing important information for optimizing structure. An optimized compound 2 exhibited in vitro and in vivo anti-gastric cancer activity partly through inhibiting the AKT and STAT3 pathways, and displayed a favorable in vivo safety profile. In summary, this paper provided a promising class of MCAs and a potential compound for the development of chemotherapeutic drugs.

BER analysis on exposure effect for optical camera communication.

The exposure effect of cameras in optical camera communication (OCC) distorts the received light pulses and generates inter-symbol interference (ISI), which adversely affects the bit error rate (BER) performance. In this Letter, we derive an analytical expression of BER based on the pulse response model of the camera-based OCC channel and analyze the impact of exposure time on BER performance considering asynchronous transmission characteristics. Numerical simulations and experimental results demonstrate that a long exposure time is beneficial in a noise-dominant communication scenario, while a short exposure time is preferable when ISI is dominant. This Letter provides a comprehensive analysis of the influence of exposure time on BER performance, offering a theoretical foundation for the design and optimization of OCC systems.

Selective Expression of a SNARE-Cleaving Protease in Peripheral Sensory Neurons Attenuates Pain-Related Gene Transcription and Neuropeptide Release.

Chronic pain is a leading health and socioeconomic problem and an unmet need exists for long-lasting analgesics. SNAREs (soluble N-ethylmaleimide-sensitive factor attachment protein receptors) are required for neuropeptide release and noxious signal transducer surface trafficking, thus, selective expression of the SNARE-cleaving light-chain protease of botulinum neurotoxin A (LCA) in peripheral sensory neurons could alleviate chronic pain. However, a safety concern to this approach is the lack of a sensory neuronal promoter to prevent the expression of LCA in the central nervous system. Towards this, we exploit the unique characteristics of Pirt (phosphoinositide-interacting regulator of TRP), which is expressed in peripheral nociceptive neurons. For the first time, we identified a Pirt promoter element and cloned it into a lentiviral vector driving transgene expression selectively in peripheral sensory neurons. Pirt promoter driven-LCA expression yielded rapid and concentration-dependent cleavage of SNAP-25 in cultured sensory neurons. Moreover, the transcripts of pain-related genes (TAC1, tachykinin precursor 1; CALCB, calcitonin gene-related peptide 2; HTR3A, 5-hydroxytryptamine receptor 3A; NPY2R, neuropeptide Y receptor Y2; GPR52, G protein-coupled receptor 52; SCN9A, sodium voltage-gated channel alpha subunit 9; TRPV1 and TRPA1, transient receptor potential cation channel subfamily V member 1 and subfamily A member 1) in pro-inflammatory cytokines stimulated sensory neurons were downregulated by viral mediated expression of LCA. Furthermore, viral expression of LCA yielded long-lasting inhibition of pain mediator release. Thus, we show that the engineered Pirt-LCA virus may provide a novel means for long lasting pain relief.

Improved Adsorption Performance of α-Fe2O3 Modified with Carbon Spheres for Cr(VI) Removal from Aqueous Solution.

Carbons spheres, easily fabricated by glucose hydrolysis, were integrated with α-Fe2O3 for removing heavy metal from contaminated water. The α-Fe2O3 particles were anchored on the surface of carbon spheres and the combination of two components provided more rough surface area, enhancing the adsorption performance of α-Fe2O3. The removal efficiency of Cr(VI) on α-Fe2O3/carbon spheres was 88% in 240 min, which was 1.93 times higher than that of pristine α-Fe2O3. The investigation on adsorption kinetics and isotherm showed that the pseudo-first-order kinetic and Langmuir isotherm models could well fit the experimental data. The adsorption rate was mainly controlled by both exterior and interior surface diffusion steps. Adsorption thermodynamics investigation proved that the Cr(VI) adsorption on α-Fe2O3/carbon spheres was an endothermic (93.32 kJ · mol-1) and spontaneous (-3.96 kJ · mol-1) physical process. The adsorption capacity was 18.7 mg · g-1 and after recycling five times, the decline of adsorption capacity of α-Fe2O3/carbon spheres was 7.8%, which indicated that the adsorbents could be recycled in the removal of Cr(VI). It indicated that the hybridization with carbon spheres could enhance the adsorption performance of α-Fe2O3, which might be used as convenient adsorbent to remove heavy metal in industry.

Full-length genomic characterization and molecular evolution of canine parvovirus in China.

Canine parvovirus type 2 (CPV-2) can cause acute haemorrhagic enteritis in dogs and myocarditis in puppies. This disease has become one of the most serious infectious diseases of dogs. During 2014 in China, there were many cases of acute infectious diarrhoea in dogs. Some faecal samples were negative for the CPV-2 antigen based on a colloidal gold test strip but were positive based on PCR, and a viral strain was isolated from one such sample. The cytopathic effect on susceptible cells and the results of the immunoperoxidase monolayer assay, PCR, and sequencing indicated that the pathogen was CPV-2. The strain was named CPV-NY-14, and the full-length genome was sequenced and analysed. A maximum likelihood tree was constructed using the full-length genome and all available CPV-2 genomes. New strains have replaced the original strain in Taiwan and Italy, although the CPV-2a strain is still predominant there. However, CPV-2a still causes many cases of acute infectious diarrhoea in dogs in China.

Synthesis and Anti-gastric Cancer Activity by Targeting FGFR1 Pathway of Novel Asymmetric Bis-chalcone Compounds.

BACKGROUP: Bis-chalcone compounds with symmetrical structures, either isolated from natural products or chemically synthesized, have multiple pharmacological activities. Asymmetric Bis-chalcone compounds have not been reported before, which might be attributed to the synthetic challenges involved, and it remains unknown whether these compounds possess any potential pharmacological activities. AIMS: The aim of this study is to investigate the synthesis route of asymmetric bis-chalcone compounds and identify potential candidates with efficient anti-tumor activity. METHOD: The two-step structural optimization of the bis-chalcone compounds was carried out sequentially, guided by the screening of the compounds for their growth inhibitory activity against gastric cancer cells by MTT assay. The QSAR model of compounds was established through random forest (RF) algorithm. The activities of the optimal compound J3 on growth inhibition, apoptosis, and apoptosis-inducing protein expression in gastric cancer cells were investigated sequentially by colony formation assay, flow cytometry, and western blotting. Further, the inhibitory effects of J3 on the FGFR1 signaling pathway were explored by Wester Blotting, siRNA, and MTT assays. Finally, the in vivo anti-tumor activity and mechanism of J3 were studied through nude mouse xenograft assay, western blotting. RESULT: 27 asymmetric bis-chalcone compounds, including two types (N and J) were sequentially designed and synthesized. Some N-class compounds have good inhibitory activity on the growth of gastric cancer cells. The vast majority of J-class compounds optimized on the basis of N3 exhibit excellent inhibitory activity on gastric cancer cell growth. We established a QSAR model (R2 = 0.851627) by applying random forest algorithms. The optimal compound J3, which has better activity, concentration-dependently inhibited the formation of gastric cancer cell colonies and led to cell apoptosis by inducing the expression of the pro-apoptotic protein cleaved PARP. J3 may exert anti-gastric cancer effects by inhibiting the activation of FGFR1/ERK pathway. Moreover, at a dose of 10 mg/kg/day, J3 inhibited tumor growth in nude mice by nearly 70% in vivo with no significant toxic effect on body weight and organs. CONCLUSION: In summary, this study outlines a viable method for the synthesis of novel asymmetric bischalcone compounds. Furthermore, the compound J3 demonstrates substantial promise as a potential candidate for an anti-tumor drug.

Spermine alleviates experimental autoimmune encephalomyelitis via regulating T cell activation and differentiation.

Multiple sclerosis (MS) is a chronic neuroinflammatory disease which causes demyelination, axonal damage and even disability. Th1 and Th17 cells, more precisely, the IFNγ/IL17a double producing CD4+ T cells, have been known to play critical roles in the pathogenesis of MS and EAE, a mouse model of MS. Polyamines not only regulate the immune system, but also are essential for the normal function of the central nervous system (CNS). In this study, we demonstrate that the supplementation of spermine (SPM), a biogenic polyamine, significantly suppresses EAE progression in both preventative and therapeutic ways. Further study suggests that spermine significantly reduces IFNγ+/IL17a-, IFNγ-/IL17a+ and IFNγ+/IL17a+ cells in periphery, and thus reducing the infiltration of these pathogenic cells into the CNS. In vitro, spermine has been shown to suppress the activation and proliferation of CD4+ T cells and also significantly impede the polarization of T effector cells in a dose-dependent manner, accompanied by the inhibition of ERK phosphorylation. Consistently, a number of MEK/ERK inhibitors (including PD0325901, FR180204 and selumetinib) have been found to mimic the effects of spermine in inhibiting CD4+ T cell activation and T effector cell differentiation. Collectively, spermine alleviates EAE progression by inhibiting CD4+ T cells activation and T effector cell differentiation in a MAPK/ERK-dependent manner, suggesting this pathway might be a target to develop effective therapies for MS.

A new nanoPCR molecular assay for detection of porcine bocavirus.

Nanoparticle-assisted polymerase chain reaction (nanoPCR) is a novel method for the rapid amplification of DNA and has been used for the detection of virus. For detection of porcine bocavirus (PBoV), a sensitive and specific nanoPCR assay was developed with a pair of primers that were designed based on NS1 gene sequences available in GenBank. Under the optimized conditions of the PBoV nanoPCR assay, the nanoPCR assay was 100-fold more sensitive than a conventional PCR assay. The lower detection limit of the nanoPCR assay was about 6.70×10(1) copies. The nanoPCR assay amplified the specific 482-bp fragment of the PBoV NS1 recombinant plasmid but did not produce any product with genomic DNA or cDNA of porcine parvovirus, porcine circovirus type II, porcine reproductive and respiratory syndrome virus, pseudorabies virus, classic swine fever virus, Encephalomyocarditis virus, Porcine Teschovirus or African swine fever virus plasmid. Of 65 clinical samples collected from diseased pigs, 73.8% and 86.2% were determined to be PBoV positive by PBoV conventional PCR and PBoV nanoPCR assay, respectively. Of 36 clinical samples from healthy pigs, 27.8% and 44.4% were PBoV positive by PBoV conventional PCR and PBoV nanoPCR assay, respectively. The nanoPCR assay will be useful for diagnosing PBoV and for studying its epidemiology and pathology.

Development and evaluation of the rVP-ELISA for detection of antibodies against porcine parvovirus.

The gene encoding the VP2 protein of porcine parvovirus (PPV) was expressed in an insect-baculovirus system. The recombinant (r) VP2 was similar antigenically/functionally to the native capsid protein as demonstrated by hemagglutination (HA), Western blotting using PPV positive sera. The purified rVP2 proteins were used as coating antigen to establish a rVP-ELISA method for detection of PPV positive and negative sera from pigs. The optimal operating conditions of the rVP-ELISA were: the concentration of rVP2 proteins coated on the wells was 2 µg/mL; the diluted concentration of serum was 1: 150 and that of the enzyme-labeled antibody was 1: 6000. A total of 596 sera were detected by this assay, and the average positive rate was 87%. Compared with France LSI kit, the result showed that the coincidence rate was 96.7%. In conclusion, the rVP2-ELISA is a sensitive and specific method for detecting antibodies against PPV.