Clinical and MRI risk factors predicting post-irradiation carotid blowout syndrome in patients with nasopharyngeal cancer.

OBJECTIVE: To explore the clinical and imaging features of nasopharyngeal cancer (NPC) complicated by acute carotid blowout syndrome (CBS), analyze the risk factors for CBS, and improve diagnostic vigilance for early intervention. METHODS: This retrospective review was conducted between January 2003 and May 2023. Altogether, 49 patients with post-irradiation NPC with CBS and 49 patients without CBS as control group were enrolled. The condition of the patients when CBS occurred was reviewed. Patient characteristics of the CBS and control groups were compared, and binary logistic regression analysis was performed to identify risk factors for CBS. RESULTS: All patients in the CBS group were conscious, and 41 patients had a Karnofsky performance assessment scale score of ≥ 70. After interventional therapy, 43 patients survived (the mean survival time of patients after CBS was 3.2 ± 2.1 years). Compared with the control group, the CBS group had a higher incidence of sphenoid sinusitis (81% vs. 52.4%), osteonecrosis (82.9% vs. 51.2%), artery exposure (29.3% vs. 4.9%), and internal carotid artery injury (61% vs. 29.3%). Osteonecrosis and artery exposure were selected as important risk factor for CBS, with p-values of 0.016 and 0.031, respectively. CONCLUSION: CBS is an important factor that affects the survival of patients with NPC. If internal carotid artery injury, artery exposure, sphenoid sinusitis, and osteonecrosis are present, especially the latter two signs, the possibility of CBS should be considered.

The floodplain inundation history of the Murray-Darling Basin through two-monthly maximum water depth maps.

With growing concerns over water management in rivers worldwide, researchers are seeking innovative solutions to monitor and understand changing flood patterns. In a noteworthy advancement, stakeholders interested in the changing flood patterns of the Murray Darling Basin (MDB) in Australia, covering an area of 1 million km2, can now access a consistent timeseries of water depth maps for the entire basin. The dataset covers the period from 1988 to 2022 at two-monthly timestep and was developed using remotely sensed imagery and a flood depth estimation model at a spatial resolution of ≈30 m, providing a comprehensive picture of maximum observed inundation depth across the MDB. Validation against 13 hydrodynamic model outputs for different parts of the MDB yielded a mean absolute error of 0.49 m, demonstrating reasonable accuracy and reliability of the dataset. The resulting dataset is best suited to system-wide analysis but might also be useful for those interested in the history of flooding at specific locations in the system. We provide the dataset, visualization tools, and examples to support ongoing research.

Sambucus williamsii Hance maintains bone homeostasis in hyperglycemia-induced osteopenia by reversing oxidative stress via cGMP/PKG signal transduction.

BACKGROUND: Sambucus williamsii Hance (SWH) has effectively been adopted to treat joint and bone disorders. Diabetes-induced osteopenia (DOP) is caused primarily by impaired bone formation as a result of hyperglycemia. We had previously demonstrated that SWH extract accelerated fracture healing and promoted osteoblastic MC3T3-E1 cell proliferation and osteogenic differentiation. This study assessed the impacts of SWH extract on diabetes-induced bone loss and explored the mechanisms underlying its osteoprotective effects. METHODS: This work employed MC3T3-E1 cell line for evaluating how SWH extract affected osteogenesis, oxidative stress (OS), and the underlying mechanism in vitro. Streptozotocin-induced osteopenia mouse model was applied with the purpose of assessing SWH extract's osteoprotection on bone homeostasis in vivo. RESULTS: The increased OS of MC3T3-E1 cells exposed to high glucose (HG) was largely because of the upregulation of pro-oxidant genes and the downregulation of antioxidant genes, whereas SWH extract reduced the OS by modulating NADPH oxidase-4 and thioredoxin-related genes by activating cyclic guanosine monophosphate (cGMP) production and increasing the level of cGMP-mediated protein kinase G type-2 (PKG2). The oral administration of SWH extract maintained bone homeostasis in type 1 diabetes mellitus (T1DM) mice by enhancing osteogenesis while decreasing OS. In bones from hyperglycemia-induced osteopenia mice and HG-treated MC3T3-E1 cells, the SWH extract achieved the osteoprotective effects through activating the cGMP/PKG2 signaling pathway, upregulating the level of antioxidant genes, as well as downregulating the level of pro-oxidant genes. CONCLUSION: SWH extract exerts osteoprotective effects on hyperglycemia-induced osteopenia by reversing OS via cGMP/PKG signal transduction and is a potential therapy for DOP.

Carotid wall imaging with 3D_T2_FFE: sequence parameter optimization and comparison with 3D_T2_SPACE.

Similar to sampling perfection with application-optimized contrast using different flip angle evolutions (SPACE), T2-weighted fast field echo (FFE) also has a black blood effect and a high imaging efficiency. The purpose of this study was to optimize 3D_T2_FFE and compare it with 3D_T2_SPACE for carotid imaging. The scanning parameter of 3D_T2_FFE was optimized for the imaging of the carotid wall. Twenty healthy volunteers and 10 patients with carotid plaque underwent cervical 3D_T2_FFE and 3D_T2_SPACE examinations. The signal-to-noise ratios of the carotid wall (SNRwall) and lumen (SNRlumen), and the contrast-to-noise ratios between the wall and lumen (CNRwall_lumen) were compared. The incidence of the residual flow signal at the carotid bifurcation and the grades of flow voids in the cerebellopontine angle region in the two sequences were also compared. The reproducibility of the two sequences was tested. No significant difference was observed between the two sequences in terms of the SNRwall of healthy individuals and patients (P = 0.132 and 0.102, respectively). The SNRlumen in the 3D_T2_FFE images was lower than that in the 3D_T2_SPACE images. No significant difference was observed between the two sequences in terms of the CNRwall-lumen. The incidence of the residual flow signal at the carotid bifurcation in 3D_T2_FFE was significantly lower than that in 3D_T2_SPACE. The grades of flow suppression in the cerebellopontine angle region in 3D_T2_SPACE was lower than that in 3D_T2_FFE. Both sequences showed excellent inter-and intra-observer reproducibility. Compared to 3D_T2_SPACE, 3D_T2_FFE showed stronger flow suppression while maintaining good imaging quality, which can be used as an alternative tool for carotid imaging.

Piezoelectric property comparison of two-dimensional ZnO nanostructures for energy harvesting devices.

In this paper, experimental and theoretical studies of the piezoelectric effect of two-dimensional ZnO nanostructures, including straight nanosheets (SNSs) and curved nanosheets (CNSs) are conducted. The results show that the CNSs have a great advantage in piezoelectric property over the SNSs; the maximum output current of the NG based on CNSs was measured to be about 260 nA, much higher than that generated by SNSs. For comparatively analyzing the working mechanics of both NGs, the piezopotential distribution of both CNS and SNS structures was studied using the finite element method. The simulation result that the piezopotential generated by CNSs is always much larger than that generated by SNSs in the case of lateral bending, has more advantages for piezoelectric NGs than the SNSs. This work may provide guidance for structural optimization of piezoelectric nanogenerators and designing high-performance self-powered strain sensors.

Sandwich fusion of CBM9_2 to enhance xylanase thermostability and activity.

Used as model for sandwich fusion, a mesophilic Aspergillus niger GH11 xylanase (Xyn) was fused into C2-Xyn-C2 with a thermophilic Thermotaga maritima GH10 xylanase carbohydrate-binding module CBM9_2 (C2). Linearized plasmids C2-pET20b-C2-Xyn were amplified from template pET20b-Xyn-C2 with a 4.3 kb C2-pET20b megaprimer, ligated into circular plasmids in blunt-end ligation, and transformed into E. coli BL21 (DE3) cells. The C2-Xyn-C2 had optimum activity at 45 °C and pH 4.2, a 2.85 h thermal inactivation half-life at 80 °C and a 8.69 h at 50 °C, with the 8.69 h value 24.8-, 7.5-, and 7.1-fold longer than the Xyn and single terminal fusion enzymes Xyn-C2, and C2-Xyn. Thermodynamics showed that the enzyme had a 1.8 °C higher melting temperature, lower values ΔS, ΔΔG, and a denser structure than the Xyn. Kinetics showed that the C2-Xyn-C2 catalytic efficiency was 1.2-~6-fold and 2.7-~7.9-fold higher on beechwood and oat-spelt xylan than those of the enzymes Xyn, Xyn-C2, and C2-Xyn. The sandwich fusion evolved the xylanase with "armor-hands" to enhance simultaneously thermostability and activity in quality.

T2-weighted balanced steady-state free procession MRI evaluated for diagnosing placental adhesion disorder in late pregnancy.

OBJECTIVE: This study evaluated the imaging characteristics and accuracy of T2-weighted (T2W) balanced steady-state free procession (b-SSFP) magnetic resonance imaging, relative to b-SSFP or single-shot fast spin echo (SSFSE), for the diagnosis of placental adhesion disorder (PAD). METHODS: Fifty-one pregnant patients suspected of PAD were examined with T2W b-SSFP, b-SSFP and SSFSE. The image types were independently analysed for signs of PAD: abnormal placental bulge (APB), dark intraplacental bands (DIB), placental heterogeneity (PH) and placental protrusion into adjacent structures (PPAS). The sequences were compared for muscle-to-placenta signal ratio, signs of PAD and area under the receiver operating characteristic curve (AUC) for diagnostic accuracy of PAD. RESULTS: PAD was confirmed in 34 women. The muscle-to-placenta signal ratio was highest in the T2W b-SSFP. The diagnostic rates of APB in T2W b-SSFP were comparable to that of b-SSFP, but were significantly higher than that of SSFSE. The rates of PH in SSFE were comparable to that of b-SSFP, but both were significantly lower than that of T2W b-SSFP. The rates of DIB were significantly higher in T2W b-SSFP images compared with SSFSE. Rates of PPAS were comparable among three sequences. The AUCs of the T2W b-SSFP, b-SSFP and SSFSE were 0.966, 0.890 and 0.823, respectively. CONCLUSION: T2W b-SSFP has high diagnostic accuracy for PAD relative to SSFSE or b-SSFP, which may be due to its high SNR, T2-weighting and lack of blur. KEY POINTS: • Signal myometrium-to-placenta ratio was highest in the T2W b-SSFP images. • Diagnostic rate of APB in T2W b-SSFP was highest. • Diagnostic rate of DIB was higher in T2W b-SSFP than in SSFSE. • Diagnostic rate of PH in T2W b-SSFP was highest. • Maximum AUC for diagnostic accuracy of PAD was in T2W b-SSFP.

A Multimodal Magnetic Resonance Imaging Study of Recovery of Consciousness in Severe Traumatic Brain Injury: Preliminary Results.

Accurate and reliable assessment of the conscious state of patients with severe traumatic brain injury (TBI) is vital for their future management. The purpose of the present study is to find an effective and accurate magnetic resonance imaging (MRI) method for predicting recovery of consciousness in patients with severe TBI. Multimodal MR techniques, including structural MRI, MR spectroscopy (MRS), diffusion tensor imaging (DTI), were used to evaluate brain damage in 58 patients with severe TBI. Statistical analysis compared imaging results and recovery over a relatively long period to find the most potent prognostic indicators and predictive method. A total 33 patients gained recovery of consciousness (RC), and 25 did not (NRC). Compared with the RC group, those in the NRC group had a significantly lower N-acetylaspartate to creatine (NAA/Cr) ratio of pons (1.43 ± 0.54 vs. 1.70 ± 0.42), more fiber lines (1046.3 ± 100.8 vs. 975.6 ± 128.1), less peripheral grey matter (pgrey) (579.23 ± 78.85 vs. 638.23 ± 61.16), lower fractional anisotropy (FA) of fibers (0.42 ± 0.04 vs. 0.45 ± 0.03), older age (43.08 ± 14.61 vs. 30.57 ± 12.89), and higher apparent diffusion coefficient (ADC) of fibers (0.99 ± 0.14 vs. 0.89 ± 0.06); all p < 0.05. Age, pgrey, ADC of fibers, NAA/Cr of pons were selected by logistic regression analysis to predict RC, with p values of 0.033 and 0.031, 0.035, 0.030, respectively. Age, pgrey, ADC of fibers, NAA/Cr of pons are effective indicators in the predictive model of RC.

Provably-secure (Chinese government) SM2 and simplified SM2 key exchange protocols.

We revisit the SM2 protocol, which is widely used in Chinese commercial applications and by Chinese government agencies. Although it is by now standard practice for protocol designers to provide security proofs in widely accepted security models in order to assure protocol implementers of their security properties, the SM2 protocol does not have a proof of security. In this paper, we prove the security of the SM2 protocol in the widely accepted indistinguishability-based Bellare-Rogaway model under the elliptic curve discrete logarithm problem (ECDLP) assumption. We also present a simplified and more efficient version of the SM2 protocol with an accompanying security proof.

Synthesis, in vitro antimicrobial and cytotoxic activities of novel pyrimidine-benzimidazol combinations.

A series of novel 4-substituted-2-{[(1H-benzo[d]imidazol-2-yl)methyl] thio}-6-methylpyrimidine derivatives were designed, synthesized and evaluated for their cytotoxic activities against four human cancer cell lines and inhibitory activities against five type culture strains in vitro. Some of synthetic pyrimidine-benzimidazol combinations showed good inhibitory activities against Stenotrophomonas maltophilia, especially compounds 7b and 7c. Compounds 7a and 7d exhibited enhanced activities against MGC-803 in vitro, when compared to 5-Fu.

Hipbone biomechanical finite element analysis and clinical study after the resection of ischiopubic tumors / 中国医学科学杂志(英文版)

<p><b>OBJECTIVE</b>To investigate the changes of hipbone biomechanics after the resection of ischiopubic tumors and their relationships with the complications in the convalescent stage, and directing the postoperative pelvic reconstruction.</p><p><b>METHODS</b>DICOM data were used to create an intact hipbone finite element model and postoperative model. The biomechanical indices on the same region in the two models under the same boundary condition were compared. The differences of displacement, stress, and strain of the two models were analyzed with statistical methods.</p><p><b>RESULTS</b>The distribution areas of the hipbone nodes' displacement, stress, and strain were similar before and after the simulated operation. The sacroiliac joint nodes' displacement (P=0.040) and strain (P=0.000), and the acetabular roof nodes' stress (P=0.000) and strain (P=0.005) of two models had significant differences, respectively.But the sacroiliac joint nodes' stress (P=0.076) and the greater sciatic notch nodes' stress (P=0.825) and strain (P=0.506) did not have significant differences.</p><p><b>CONCLUSIONS</b>The resection of ischiopubic tumors mainly affect the biomechanical states of the homolateral sacroiliac joint and acetabular roof. The complications in the convalescent stage are due to the biomechanical changes of the sacroiliac joint and the acetabular roof and disappearances of the stabilization and connection functions of the pubic symphysis and superior ramus of pubis.</p>

[Magnetic resonance myocardial perfusion imaging for evaluating myocardial viability after myocardial infarction].

OBJECTIVE: To assess the value of magnetic resonance (MR) myocardial perfusion imaging (MRMPI) in evaluating the myocardial viability in patients with myocardial infarction. METHODS: MRMPI was performed in 51 patients with myocardial infarction using a 1.5 T MR scanner. All the patients were examined using IR-turbo FLASH sequence during the first-pass and delayed phase 5-30 min after injection of 0.1 mmol/kg Gd-DTPA at the rate of 4 ml/s. The short axis images were acquired during the first-pass, and both the short axis and long axis images were obtained during the delayed phase. The left ventricular wall on the short-axis slice was divided into 8 segments. A correlative study of the results of the rest and stress (99m)Tc single photon emission computed tomography (SPECT) was carried out in 21 patients. RESULTS: In the 51 patients with myocardial infarction, 42(82.3%) showed hypoperfusion during the first-pass imaging and 50(98%) had delayed hyperenhancement. In the 21 patients receiving SPECT, 48 nonviable segments was detected among the 168 segments scanned by (99m)TcSPECT, and MRMPI showed delayed hyperenhancement in all the infracted areas. Of the 120 viable segments detected by rest and stress (99m)Tc SPECT, 97 segments (80.8%) were found to be free of delayed hyperenhancement by MRMPI. With the rest and stress (99m)Tc SPECT as the reference, the sensitivity and the specificity of MRMPI were 100.0% and 80.8%, respectively. CONCLUSION: MRMPI allows effective identification of the myocardial viability and nonviability as well as the severity and extent of the myocardial infraction.

[CT hepatic volume measurement combined with CT perfusion imaging in evaluating the hepatic functional reserve].

OBJECTIVE: To investigate the application of CT hepatic volume measurement combined with CT perfusion imaging (CTPI) by Spiral CT in evaluating the hepatic functional reserve in cirrhosis. METHODS: CT volume measurement of livers was performed in 32 patients with cirrhosis and 20 patients with normal livers. CTPI had been taken in 25 patients with cirrhosis and 20 patients with normal livers. The hepatic volume, parameter of blood flow perfusion, and liver volume-perfusion index were observed and analyzed. Correlations between graded fractions of hepatic function and liver volume, parameter of perfusion, and liver volume-perfusion index were also analyzed. RESULTS: The values of liver volumes (LV, LVs) reduced gradually (P<0.01) among the groups of hepatic function Grade A, B, and C. The values of the hepatic portal perfusion (HPP), total liver perfusion (TLP), hepatic arterial perfusion index (HAI), and portal perfusion index (PPI) of the cirrhosis group were significantly lower than those of the normal ones (P<0.01). The values of the HPP reduced gradually among Grade A, B, and C (P<0.05 or P<0.01). The values of PPI reduced significantly between Grade C and Grade A, B (P<0.05 or P<0.01). The liver volume-perfusion indexes (VPI, VPIs, VPPI, VPPIs) reduced gradually among Grade A, B, and C (P<0.05 or P<0.01). The correlation between liver volume-perfusion indexes and graded fractions of hepatic function was higher than other indexes, among which the correlation of VPPIs was the highest. CONCLUSION: Changes of volume and blood flow perfusion of the liver are related to the clinical grade of hepatic function. The CT volume measurement combined with CTPI will be a more comprehensive way in evaluating hepatic functional reserve.

Characterizing warfare in red teaming.

Red teaming is the process of studying a problem by anticipating adversary behaviors. When done in simulations, the behavior space is divided into two groups; one controlled by the red team which represents the set of adversary behaviors or bad guys, while the other is controlled by the blue team which represents the set of defenders or good guys. Through red teaming, analysts can learn about the future by forward prediction of scenarios. More recently, defense has been looking at evolutionary computation methods in red teaming. The fitness function in these systems is highly stochastic, where a single configuration can result in multiple different outcomes. Operational, tactical and strategic decisions can be made based on the findings of the evolutionary method in use. Therefore, there is an urgent need for understanding the nature of these problems and the role of the stochastic fitness to gain insight into the possible performance of different methods. This paper presents a first attempt at characterizing the search space difficulties in red teaming to shed light on the expected performance of the evolutionary method in stochastic environments.

[Value of "low-signal zone" sign in the diagnosis of brain abscess in the capsule period].

OBJECTIVE: To evaluate the value of "low-signal zone" sign in the diagnosis of brain abscess in the capsule period. METHODS: The conventional MRI was performed pre-therapy in 21 patients with brain abscess in the capsule period and 25 patients with vesica-astrocytomas. We analyzed the pathologic basis of "low-signal zone" sign in brain abscess and compared the frequency and shape of "low-signal zone" sign in brain abscess and vesica-astrocytomas. RESULTS: The "low-signal zone" sign in MRI occurred more frequently in brain abscess (85.7%, 18/21) than in vesica-astrocytomas (52.0%, 13/25). The "low-signal zone" sign in the former was intact, while that in the latter was not. CONCLUSION: The "low-signal zone" sign is helpful to diagnose brain abscess in the capsule period, and is valuable to differentiate brain abscess and vesica-astrocytomas.