Quantum ghost imaging of a vector field.

Quantum ghost image technique utilizing position or momentum correlations between entangled photons can realize nonlocal reconstruction of the image of an object. In this work, based on polarization entanglement, we experimentally demonstrate quantum ghost imaging of vector images by using a geometric phase object. We also provide a corresponding theoretical analysis. Additionally, we offer a geometrical optics path explanation of ghost imaging for vector fields. The proposed strategy offers new insights into the fundamental development of ghost imaging and also holds great promise for developing complex structured ghost imaging techniques. Our work expanding the principle of ghost imaging to spatially varying vector beams will lead to interesting developments of this field.

Generating an M2 × N2 spot array with a dual-period hybrid Dammann grating fabricated using maskless projection lithography.

The Dammann grating (DG), which redistributes a collimated laser beam into a spot array with a uniform intensity, is a widely adopted approach for profile measurement. Conventional DGs for dense spot projection are binary phase gratings with precisely designed groove structures, which suffer from low efficiency, poor uniformity, and a hard-to-fabricate fine feature size when utilized for a large field of view (FOV). Here, we propose a new, to the best of our knowledge, hybrid DG architecture consisting of two different grating periods which effectively generates an engineering M2 × N2 spot array with a non-complex structural design. As a proof-of-concept, a dual-period hybrid DG with a two-scale grating period ratio of 11.88 µm/95.04 µm (∼1/8) is designed and fabricated as a means to generate a dense 72 × 72 diffraction spot array with a FOV of 17° × 17°. In addition, the DG exhibits superior performance, with a high efficiency (>60%) and a low non-uniformity (<18%) at a wavelength of 532 nm. This kind of hybrid DG constructed from photoresist patterns with a minimum feature size of ∼1.2 µm can be perfectly fabricated by maskless projection lithography for large-scale and low-cost production. The proposed dual-period hybrid DG can pave the way for depth-perception-related applications such as face unlocking and motion sensing.

Ultralow-power all-optical switching via a chiral Mach-Zehnder interferometer.

It is a challenge for all-optical switching to simultaneous achieve ultralow power consumption, broad bandwidth and high extinction ratio. We experimentally demonstrate an ultralow-power all-optical switching by exploiting chiral interaction between light and optically active material in a Mach-Zehnder interferometer. We achieve switching extinction ratio of 20.0 ± 3.8 and 14.7 ± 2.8 dB with power cost of 66.1 ± 0.7 and 1.3 ± 0.1 fJ/bit, respectively. The bandwidth of our all-optical switching is about 4.2 GHz. Moreover, our all-optical switching has the potential to be operated at few-photon level. Our scheme paves the way towards ultralow-power and ultrafast all-optical information processing.

Self-healing of a heralded single-photon Airy beam.

Self-healing of an Airy beam during propagation is of fundamental interest and also promises important applications. Despite many studies of Airy beams in the quantum regime, it is unclear whether an Airy beam only including a single photon can heal after passing an obstacle because the photon may be blocked. Here we experimentally observe self-healing of a heralded single-photon Airy beam. Our observation implies that an Airy wave packet is robust against obstacle caused distortion and can restore even at the single-photon level.

In Vivo Self-Assembly Induced Cell Membrane Phase Separation for Improved Peptide Drug Internalization.

Therapeutic peptides have been widely concerned, but their efficacy is limited by the inability to penetrate cell membranes, which is a key bottleneck in peptide drugs delivery. Herein, an in vivo self-assembly strategy is developed to induce phase separation of cell membrane that improves the peptide drugs internalization. A phosphopeptide KYp is synthesized, containing an anticancer peptide [KLAKLAK]2 (K) and a responsive moiety phosphorylated Y (Yp). After interacting with alkaline phosphatase (ALP), KYp can be dephosphorylated and self-assembles in situ, which induces the aggregation of ALP and the protein-lipid phase separation on cell membrane. Consequently, KYp internalization is 2-fold enhanced compared to non-responsive peptide, and IC50 value of KYp is approximately 5 times lower than that of free peptide. Therefore, the in vivo self-assembly induced phase separation on cell membrane promises a new strategy to improve the drug delivery efficacy in cancer therapy.

In vivo SPECT imaging of Tc-99 m radiolabeled exosomes from human umbilical-cord derived mesenchymal stem cells in small animals.

Extracellular vesicles derived from human umbilical cord-derived mesenchymal stem cells (UCMSC-EVs) have been postulated to have therapeutic potential for various diseases. However, the biodistribution and pharmacokinetics of these vesicles are still unclear. For a better understanding of the in vivo properties of UCMSC-EVs, in the present study, these vesicles were first radiolabeled with Technetium-99 m (99mTc-UCMSC-EVs) and evaluated using in vivo single photon emission computed tomography (SPECT) imaging and biodistribution experiments. SPECT images demonstrated that the liver and spleen tissues mainly took up the 99mTc-UCMSC-EVs. The biodistribution study observed slight uptake in the thyroid and stomach, indicating that 99mTc-UCMSC-EVs was stable at 24 h in vivo. The pharmacokinetic analyses of the blood half-life demonstrated the quick distribution phase (0.85 ±â€¯0.28 min) and elimination phase (25.22 ±â€¯20.76 min) in mice. This study provides a convenient and efficient method for 99mTc-UCMSC-EVs preparation without disturbing their properties. In conclusion, the biodistribution, quick elimination, and suitable stability in vivo of 99mTc-UCMSC-EVs were quantified by the noninvasive imaging and pharmacokinetic analyses, which provides useful information for indication selection, dosage protocol design, and toxicity assessment in future applications.

Sonoactivated Cascade Fenton Reaction Enhanced by Synergistic Modulation of Electron-Hole Separation for Improved Tumor Therapy.

Chemodynamic therapy (CDT) is an emerging targeted treatment technique for tumors via the generation of highly cytotoxic hydroxyl radical (·OH) governed by tumor microenvironment-assisted Fenton reaction. Despite high effectiveness, it faces limitations like low reaction efficiency and limited endogenous H2 O2 , compromising its therapeutic efficacy. This study reports a novel platform with enhanced CDT performance by in situ sono-activated cascade Fenton reaction. A piezoelectric g-C3 N4 (Au-Fe-g-C3 N4 ) nanosheet is developed via sono-activated synergistic effect/H2 O2 self-supply mediated cascade Fenton reaction, realizing in situ ultrasound activated cascade Fenton reaction kinetics by synergistic modulation of electron-hole separation. The nanosheets consist of piezoelectric g-C3 N4 nanosheet oxidizing H2 O to highly reactive H2 O2 from the valence band, Fe3+ /Fe2+ cycling activated by conduction band to generate ·OH, and Au nanoparticles that lower the bandgap and further adopt electrons to generate more 1 O2 , resulting in improved CDT and sonodynamic therapy (SDT). Moreover, the Au-Fe-g-C3 N4 nanosheet is further modified by the targeted peptide to obtain P-Au-Fe-g-C3 N4 , which inhibits tumor growth in vivo effectively by generating reactive oxygen species (ROS). These results demonstrated that the sono-activated modulation translates into a high-efficiency CDT with a synergistic effect using SDT for improved anti-tumor therapy.

Laryngoscopic characteristics related to the risk of cancerization of vocal cord leukoplakia.

BACKGROUND: The diagnosis of vocal cord leukoplakia mainly relies on laryngoscopy. The morphology of vocal cord leukoplakia under laryngoscope is closely related to the pathological nature of leukoplakia. The specific manifestations associated with high-risk vocal cord leukoplakia remain to be explored. OBJECTIVE: To investigate the characteristics of low-risk and high-risk vocal cord leukoplakia under conventional white light imaging (WLI) laryngoscopy and its correlations with narrow band imaging (NBI) laryngoscopy. METHODS: One hundred and seventy-five cases of vocal cord leukoplakia were divided into low-risk and high-risk groups. The characteristics of low-risk and high-risk vocal cord leukoplakia under WLI laryngoscopy and its correlations with NBI laryngoscopy were analyzed. RESULTS: Logistic regression analysis showed that thickness and hyperemia were independent factors (p < .05). Hyperemia had a strong consistency with the visualization of spots under NBI laryngoscopy (kappa = 0.758). The sign of hyperemia and the NBI classification had equivalent diagnostic efficacy for predicting the risk of cancerization of vocal cord leukoplakia. CONCLUSION: The sign of hyperemia under WLI laryngoscopy is significantly correlated with the visualized spots under NBI laryngoscopy. Hyperemia is an important feature for predicting malignant potential of vocal cord leukoplakia.

Mesenchymal stem cell exosomes as a cell-free therapy for nerve injury-induced pain in rats.

Nerve injury-induced neuropathic pain is difficult to treat. In this study, we used exosomes derived from human umbilical cord mesenchymal stem cell (UCMSC) as a cell-free therapy for nerve injury-induced pain in rats. Isolated UCMSC exosomes range in size from 30 to 160 nm and contain CD63, HSP60, and CD81 exosome markers. After L5/6 spinal nerve ligation surgery, single intrathecal injection of exosomes reversed nerve ligation-induced mechanical and thermal hypersensitivities of right hindpaw of rats at initial and well-developed pain stages. Moreover, continuous intrathecal infusion of exosomes achieved excellent preventive and reversal effects for nerve ligation-induced pain. In immunofluorescent study, lots of Exo-green-labelled exosomes could be found majorly in the ipsilateral L5 spinal dorsal horn, dorsal root ganglion, and peripheral axons, suggesting the homing ability of UCMSC exosomes. They also appeared in the central terminals or cell bodies of IB4, CGRP, and NF200 sensory neurons. In addition, exosome treatment suppressed nerve ligation-induced upregulation of c-Fos, CNPase, GFAP, and Iba1. All these data suggest that the analgesic effects of exosomes may involve their actions on neuron and glial cells. Exosomes also inhibited the level of TNF-α and IL-1ß, while enhanced the level of IL-10, brain-derived neurotrophic factor, and glial cell line-derived neurotrophic factor in the ipsilateral L5/6 dorsal root ganglion of nerve-ligated rats, indicating anti-inflammatory and proneurotrophic abilities. Protein analysis revealed the content of vascular endothelial growth factor C, angiopoietin-2, and fibroblast growth factor-2 in the exosomes. In summary, intrathecal infusion of exosomes from UCMSCs may be considered as a novel therapeutic approach for nerve injury-induced pain.

Astragaloside VI and cycloastragenol-6-O-beta-D-glucoside promote wound healing in vitro and in vivo.

BACKGROUND: Astragalus genus includes most of the common, historical herbal medicines that have various applications in Asian countries. However, clinical data and mechanistic insights into their actions are still lacking. PURPOSE: In this study, we aimed to examine the effects of astragalosides on wound healing in vitro and in vivo, as well as the underlying mechanisms of these actions. METHODS: The wound healing activity of astragalosides was investigated in human HaCaT keratinocytes, human dermal fibroblast (HDF) cells, and murine models of wound healing. RESULTS: All eight astragalosides studied enhanced epidermal growth factor receptor (EGFR) activity in HaCaT cells. Among them, astragaloside VI (AS-VI) showed the strongest EGFR activation. Consistently, AS-VI and cycloastragenol-6-O-beta-D-glucoside (CMG), which is the major metabolite of astragalosides, enhanced extracellular signal-regulated kinase (ERK) activity in a concentration-dependent manner. In agreement, both compounds induced EGFR-dependent cell proliferation and migration in HaCaT and HDF cells. In addition, we showed that AS-VI and CMG accelerated the healing of both sterile and infected wounds in vivo. These effects were associated with increased angiogenesis in the scar tissue. CONCLUSION: AS-VI and CMG increased the proliferation and migration of skin cells via activation of the EGFR/ERK signalling pathway, resulting in the improvement of wound healing in vitro and in vivo. These findings indicate the therapeutic potential of AS-VI and CMG to accelerate wound healing; additionally, they suggest the mechanistic basis of this activity.

[Hereditary hemorrhagic telangiectasia caused by mutation in intron 4 of ALK1 gene: analysis of a HTT family].

OBJECTIVE: To investigate the molecular pathogenesis of hereditary hemorrhagic telangiectasia (HHT). METHODS: Peripheral blood samples were collected from a HTT family, including the proband, female, aged 48, and her mother, elder brother, elder sister, younger brother, and son. HHT gene mutations were identified by PCR-SSCP and DNA sequencing and confirmed by reverse sequencing. Ectopic transcripts of RT-PCR were used to confirm the characteristics of the mutation in non-canonical splicing site (IV S4 + 3 a > t). RESULTS: A mutational segment of PCR product of exon 4, exon-intron boundaries and the 3', 5' untranslated sequence of ALK1 gene was identified by PCR-SSCP. The mutational segment was analyzed by DNA sequencing. An IV S4 + 3 a > t mutation was found, causing splicing abnormality of intron 4 and exon 3 skipping. CONCLUSION: A splicing pattern of the IV S4 + 3 a > t mutation has been reported among Chinese HHT2 patients for the first time.

[Reverse small saphenous vein-sural neurovascular island flap for t he reconstruction ofsoft tissue defect on foot and ankle in children].

OBJECTIVE: To investigate the clinical application of reversed small saphenous vein-sural neurovascular island flap for reconstruction of soft tissue defect on foot and ankle in children. METHODS: From July 2006 to June 2008, 8 children with soft tissue defects on foot, heel or ankle were treated with reversed small saphenous vein-sural neurovascular island flaps. The size of flaps ranged from 6 cm x 5 cm to 9 cm x 7 cm. The upper margin of the flaps reached the upper third of cruris, with 1 case reaching the transverse line of popliteal fossa. RESULTS: All the flaps survived. The patients were followed up for 1 - 17 months with good aesthetic and functional results. The growth of the two legs had no difference. The sensation of the flaps improved with no heel ulcer and no dysfunction at the donor site. The upper boundary of flaps can reach the upper third of the cruris even the reansverse line of popliteal fossa. The rotation point of the flaps located at 4 - 6 cm above the lateral ankle in children. CONCLUSIONS: The reversed small saphenous vein-sural neurovascular island flap in children has a reliable survival area. The operation is easily performed without any obvious influence on the growth of the operated cruris. It is a good reconstructive method for soft tissue defect in foot and ankle.

[Significance of the expression of P53 protein and P21WAF1 protein in the gastric carcinoma tissues associated with Epstein-Barr virus (EBV) infections].

BACKGROUND: To study the difference in gene expression between the EBV associated gastric carcinoma (EBVaGC) tissues. To explore the mechanism of gastric carcinoma pathogenesis initiated by EBV. METHODS: In situ hybridization was used to study the frequencies of EBV small RNA expression in 155 cases of gastric carcinoma tissues. The expression levels of P53 protein and P21WAF1 protein were detected by immunohistochemistry in all gastric carcinoma tissues. RESULTS: The expression of EBV small RNA was positive in 10 out of 155 cases (6.45%). The expression of P53 protein was weakly positive in 4 of the 10 cases. The expression level of P53 protein in EBVaGC was much lower than that in EBVnGC and was weakly positive in 30 of 145 cases with EBVnGC). P21WAF1 expression was detected in 7 of 10 cases with EBVaGC, but in 55 out of 145 cases with EBVaGC, P21WAF1 expression in EBVaGC was much higher than that in EBVnGC. CONCLUSION: There seems existing a special mechanism of pathogenesis in EBVaGC. In which P53 gene mutation may not play an important role.

[Clinical observation of the efficacy of MEBO in the treatment of burn patients with burn area over 50% TBSA].

OBJECTIVE: To observe the effectiveness of MEBO in the treatment of burn patients with burn area over 50% TBSA. METHODS: Two hundred and ninety-eight patients hospitalized in our hospital from May of 1991 to December of 2003 with burn area over 50% TBSA, who had MEBO treatment before hospitalization, were enrolled in the study as the experiment (E) group. Another group of 300 burn patients with burn area over 50% TBSA that treated with SD-Ag cream were enrolled in the study as the control (C) group. Bacterial culture results, major changes in injury and mortality were compared between the two groups. RESULTS: There were 1 506 bacteria strains isolated from wounds in E group, and 9 main changes in injury (1679 cases) occurred with 20.8% mortality in this group. There were 353 bacteria strains isolated, with occurrence of 9 changes in injury (518 cases) and 4.7% mortality in the SD-Ag group. CONCLUSION: MEBO is much less effective for the treatment of the burn patients with large burn area compared with SD-Ag cream treatment.