Long range 3D imaging through atmospheric obscurants using array-based single-photon LiDAR.

Single-photon light detection and ranging (LiDAR) has emerged as a strong candidate technology for active imaging applications. In particular, the single-photon sensitivity and picosecond timing resolution permits high-precision three-dimensional (3D) imaging capability through atmospheric obscurants including fog, haze and smoke. Here we demonstrate an array-based single-photon LiDAR system, which is capable of performing 3D imaging in atmospheric obscurant over long ranges. By adopting the optical optimization of system and the photon-efficient imaging algorithm, we acquire depth and intensity images through dense fog equivalent to 2.74 attenuation lengths at distances of 13.4 km and 20.0 km. Furthermore, we demonstrate real-time 3D imaging for moving targets at 20 frames per second in mist weather conditions over 10.5 km. The results indicate great potential for practical applications of vehicle navigation and target recognition in challenging weather.

Heterogeneous immunogenomic features and distinct escape mechanisms in multifocal hepatocellular carcinoma.

BACKGROUND & AIMS: The presence of multifocal tumors, developed either from intrahepatic metastasis (IM) or multicentric occurrence (MO), is a distinct feature of hepatocellular carcinoma (HCC). Immunogenomic characterization of multifocal HCC is important for understanding immune escape in different lesions and developing immunotherapy. METHODS: We combined whole-exome/transcriptome sequencing, multiplex immunostaining, immunopeptidomes, T cell receptor (TCR) sequencing and bioinformatic analyses of 47 tumors from 15 patients with HCC and multifocal lesions. RESULTS: IM and MO demonstrated distinct clonal architecture, mutational spectrum and genetic susceptibility. The immune microenvironment also displayed spatiotemporal heterogeneity, such as less T cell and more M2 macrophage infiltration in IM and higher expression of inhibitory immune checkpoints in MO. Similar to mutational profiles, shared neoantigens and TCR repertoires among tumors from the same patients were abundant in IM but scarce in MO. Combining neoantigen prediction and immunopeptidomes identified T cell-specific neoepitopes and achieved a high verification rate in vitro. Immunoediting mainly occurred in MO but not IM, due to the relatively low immune infiltration. Loss of heterozygosity of human leukocyte antigen (HLA) alleles, identified in 17% of multifocal HCC, hampered the ability of major histocompatibility complex to present neoantigens, especially in IM. An integrated analysis of Immunoscore, immunoediting, TCR clonality and HLA loss of heterozygosity in each tumor could stratify patients into 2 groups based on whether they have a high or low risk of recurrence (p = 0.038). CONCLUSION: Our study comprehensively characterized the genetic structure, neoepitope landscape, T cell profile and immunoediting status that collectively shape tumor evolution and could be used to optimize personalized immunotherapies for multifocal HCC. LAY SUMMARY: Immunogenomic features of multifocal hepatocellular carcinoma (HCC) are important for understanding immune-escape mechanisms and developing more effective immunotherapy. Herein, comprehensive immunogenomic characterization showed that diverse genomic structures within multifocal HCC would leave footprints on the immune landscape. Only a few tumors were under the control of immunosurveillance, while others evaded the immune system through multiple mechanisms that led to poor prognosis. Our study revealed heterogeneous immunogenomic landscapes and immune-constrained tumor evolution, the understanding of which could be used to optimize personalized immunotherapies for multifocal HCC.

Ultrasound intima-media thickness measurement of the carotid artery using ant colony optimization combined with a curvelet-based orientation-selective filter.

PURPOSE: Automatic measurement of the intima-media thickness (IMT) from ultrasound carotid images is an important task in clinical diagnosis. Many computer-based techniques for IMT measurement have been proposed to overcome the limits of manual segmentation. However, the robustness of the algorithms would be influenced by the inherent speckle noise of ultrasound image. This paper proposed a curvelet guided ant colony optimization (CGACO) strategy that could achieve satisfied accuracy for IMT measurement with improved robustness to noise. METHODS: The curvelet-based orientation-selective (CBOS) filter was first introduced for speckle removal and edge enhancement. Different from conventional methods, CBOS filter processes the curvelet coefficients by orientations rather than by magnitude. Then, a specially designed two-leg ant colony optimization technique, combined with Otsu thresholding and Sobel edge detector, was proposed as a novel segmentation method to extract the media-adventitia (MA) and the lumen-intima (LI) boundaries. Finally, a coupled snake model was employed to further smooth the contours of MA and LI. RESULTS: In addition to 224 carotid artery images acquired from 34 participants, simulated speckled images with nine levels of noise were also included in the database. The mean absolute distance errors of CGACO for LI interface tracings, MA interface tracings, and IMT measurements were 0.030 ± 0.027, 0.039 ± 0.036, and 0.041 ± 0.036 mm, respectively. Besides, CGACO had a correlation coefficient as high as 0.992 and a bias as low as -0.008. All these measures were comparable to or better than a previous technique and the manual segmentation. On the other hand, CGACO had the highest success rate of 98.7% in the segmentation of real data. It also maintained a much higher success rate in the segmentation of simulated images with different levels of speckle noise. CONCLUSIONS: The proposed technique showed accurate IMT measurement results. Furthermore, benefiting from the CBOS filter, the robustness to noise of the algorithm was substantially improved. Therefore, CGACO could provide a reliable way to segment the carotid artery from ultrasound images and could be used in clinical practice of IMT measurement, particularly in early atherosclerotic stages.

[Effects of raloxifene combined with conjugated equine estrogen on prothrombotic state in ovariectomized rats].

OBJECTIVE: To study effects of raloxifene (RLX) with different doses of conjugated equine estrogen(CEE) on prothrombotic profiles in the ovariectomized rats model. METHODS: Total of 32 healthy female SD rats at age of 9 to 10 months were equally divided into every 8 rats at 4 groups randomly. One week after ovariectomized, they were treated by drugs, including control group with placebo(0.9% Nacl intragastric administration), RLX group with RLX 6 mg/(kg·d), RLX and low CEE group with RLX 6 mg/(kg·d) + CEE 0.07 mg/ (kg·d) and RLX and high CEE group with RLX 6 mg/ (kg·d) + CEE 0.5 mg/ (kg·d) for 10 weeks before death. Thrombin turbidimetry method was used to evaluate the plasma fibrinogen(FIB), transmitting substrate method for antithrombin III(ATIII) activity, double-antibody sandwich ELISA for plasminogen activator inhibitor 1 (PAI-1), D-dimer (D-D) and von Willebrand factor (vWF) and nitrate reductase method for nitric oxide(NO). RESULTS: (1) Coagulation and anticoagulation indicators: it was observed (1.62 ± 0.22) g/L FIB at control group, (2.02 ± 0.54) g/L at RLX group, (1.97 ± 0.16) g/L at RLX and low CEE group, (2.00 ± 0.18) g/L at RLX and high CEE group. There was a statistically significant difference between control group and any one of treatment groups (P < 0.05) and no statistical significance among those three treatment groups (P > 0.05). No significant change was observed in plasma ATIII activity among groups (P > 0.05). (2) Fibrinolytic and anti-fibrinolytic indicators: it was observed (14.1 ± 2.8) µg/L PAI-1 at control group, (20.0 ± 3.3) µg/L at RLX group, (41.5 ± 5.5) µg/L at RLX and low CEE group, (38.9 ± 6.0) µg/L at RLX and high CEE group. A remarkable increase was observed between control group and any one of treatment groups (P < 0.05) . But there was no significant difference of D-D among groups (P > 0.05) . (3) Endothelial function: it was (43 ± 7) % vWF at control group, (49 ± 5) % at RLX group, (46 ± 6) % at RLX and low CEE group, (36 ± 5) % at RLX and high CEE group. The vWF of RLX and high CEE group was the lowest among all groups (P < 0.05) . There was no difference of NO among groups (P > 0.05). CONCLUSIONS: In the different links of thrombosis, RLX gives different function and may increase the risk. CEE plays a synergism role in the matter of fibrinolysis and anti-fibrinolysis with RLX, further giving rise to thrombosis effect of RLX. And it also has a protective role in the function of vascular endothelium to some extent. But this only works with high dose.

Sperm head vacuoles--light microscopic and ultrastructural observations: a case report.

BACKGROUND: Sperm head vacuoles are easily detectable in human spermatozoa under the electron microscope. A sperm head vacuole is considered abnormal when it exceeds 20% of the head's cross-sectional area. The authors report a rare case of primary spermatozoa deformity with 100% vacuolated head and evaluate the correlation between presence of head vacuoles/nucleus vacuoles and abnormal transformation of nucleoprotamine types, defects of nucleoprotamine, and gene disorders of chromatin/chromosome/spermatogenesis. METHODS: A 43-year-old male patient with infertility came to the Reproduction Health Center, Hebei, China. Semen was examined in accordance with the WHO criteria, and the spermatozoa were counted. Two hundred spermatozoa were observed both under light microscope and the electronic microscope. RESULTS: About 50% of the spermatozoa had head deformities. In the intact spermatozoa, the heads were 100% vacuolated. Under ultrastructural observation, abnormalities were observed and two major types of spermatozoa were detected. In the head of those incompletely mature spermatozoa, four kinds of the nucleus vacuoles were observed. CONCLUSION: Abnormal spermatozoa with head vacuoles account for the patient infertility.

[Clinical observation of propofol combined with misoprostol for painless induced abortion].

OBJECTIVE: To observe the effects of propofol combined with misoprostol for painless induced abortion. METHODS: Two hundred early pregnant women, nullipara or pluripara with history of cesarean section, were randomly divided into two groups: control group receiving intravenous injection of propofol 2.5 mg/kg and then underwent induced abortion after becoming unconscious, and experimental group receiving misoprostol 200 microg intravaginally two hours before undergoing induced abortion. The effects on anesthesia, cervix dilatation, uterotonic degree, bleeding and abortion syndrome were observed. RESULTS: Anesthesia was 100% effective in both groups. No induced abortion syndrome occurred. For the effect on cervical dilatation, No.6 Hegars dilator were smoothly inserted into the cervical canal in 96 cases (96%) in the experimental group and in only 8 cases (8%) in the control group (P < 0.01). For the effect on uterotonic degree, 79 cases in the experimental group (79%) and 30 cases in the control group (30%) showed 1 approximately 2 cm of uterine contraction (P < 0.01). Seventy-five cases in the experimental group (75%) and 25 cases in the control group (25%) showed blood loss of less than 15 ml (P < 0.01). CONCLUSION: Intravenous injection of propofol combined with misoprostol administered intravaginally is effective in anesthesia and cervical dilatation with less bleeding and absence of abortion syndrome.

[Study on the fingerprints of the alkaloids in Sophora flavescens].

OBJECTIVE: To establish a method for HPLC fingerprint determination of the alkaloids in S. flavescens. METHOD: RP-HPLC, linear gradient elution, LC/MS, etc. were used to determine the fingerprint and identify the main peaks in the HPLC fingerprint. RESULT: A satisfactory method for HPLC fingerprint determination of the alkaloids in S. flavescens. was established, and 5 peaks in the HPLC fingerprint were identified. CONCLUSION: The perfect fingerprint can be obtained and the method can be used for quality control of S. flavescens.