Hepatocellular Carcinoma: Prevention, Diagnosis, and Treatment.

Hepatocellular carcinoma (HCC), the most prevalent form of liver cancer globally, poses a substantial health burden. HCC development is influenced by multiple risk factors including hepatitis B and C infections, excessive alcohol consumption, nonalcoholic steatohepatitis (NASH), and demographic variables like gender, race, and age. Although the exact etiology of HCC is not fully understood, HCC formation is a multi-step process that is contributed by the interplays of viral infection, hepatocyte oncogenic mutations, and chronic liver diseases such as alcoholic cirrhosis and NASH. Disease stage significantly impacts HCC prognosis, with 5-year survival rates ranging from 36% in early-stage cases to 13% in late-stage metastatic cases. Therefore, there is significant potential for life-saving and socioeconomic benefits through the implementation of surveillance programs and the introduction of low-cost screening measures for high-risk groups, such as ultrasound imaging and blood tests. Treatment options for HCC encompass surgery, liver transplantation, radiation therapy, chemotherapy, targeted therapy, and immunotherapy. Despite therapeutic advances, the treatment of advanced HCC remains a challenge. The prognosis of advanced HCC could be greatly improved with continued efforts in prevention, early detection, and treatment development. These efforts will ultimately lead to improved patient outcomes and increased chances of long-term survival.

A channel-homogenized micro gas chromatography column for light alkane separation with uniform HKUST-1 stationary phase.

BACKGROUND: The micro gas chromatography column (µGCC) is one of the key components of the miniaturized gas chromatography system. However, light alkanes are difficult to be separated by a micro gas chromatography column, especially for methane and ethane, because the length of µGCC is limited by the area of a silicon substrate. More importantly, the heterogeneous microchannel surface formed by silicon glass bonding causes uneven stationary phase coating and the forces between the untreated microchannel surfaces and the stationary phase materials are weak, which will prevent the improvement of separation performance. RESULTS: In this paper, a micro gas chromatography column (µGCC) with uniform HKUST-1 stationary phase is reported. Significantly, an alumina film prepared by the atomic layer deposition (ALD) technique is used to homogenize the heterogeneous microchannels. The alumina is a hydrophilic material and the alumina made by the ALD technique is uniform. The forces between hydrophilic alumina film and HKUST-1 are strong, which can greatly improve the coating uniformity of the hydrophilic stationary phase HKUST-1. The test results show that the µGCC could baseline separate the light alkane mixtures (CH4, C2H6, C3H8, and C4H10) at the high testing temperature of 120 °C. The maximum resolution of the difficult-separated methane and ethane reached 19.2, which is 108 % higher than the µGCC using the same stationary phase without homogenizing the microchannel inner surface. SIGNIFICANCE: The µGCC uses ALD alumina film to homogenize the microchannel inner surface; meanwhile, hydrophilic ALD alumina has a strong electrostatic attraction with the hydrophilic stationary phase HKUST-1. Homogeneous microchannel surface and strong electrostatic attraction are favorable to obtain uniform stationary phase which greatly improves the separation performance, resulting in a large resolution for methane and ethane. The µGCC has broad application prospects in light alkane separation.

Exploring sleep characteristics in Chinese patients with narcolepsy: insights from the nocturnal sleep onset rapid eye movement period (nSOREMP).

STUDY OBJECTIVES: This study aims to investigate the unique characteristics and clinical significance of the nocturnal sleep onset rapid eye movement period (nSOREMP) in the Chinese population with narcolepsy, enhancing our understanding and management of the disorder globally. METHODS: This retrospective analysis investigated narcolepsy in Chinese patients from six hospitals, using International Classification of Sleep Disorders. A parallel retrospective analysis of the Chinese Clinical Sleep Database (CCSD) focused on polysomnography (PSG) records was conducted to evaluate nSOREMP prevalence in other sleep disorders. RESULTS: The study found a 2.51% nSOREMP prevalence in other sleep disorders of CCSD. Significant differences in age, N2 and rapid eye movement (REM) percentages, REM latency, and various indexes were noted among narcolepsy with/without nSOREMP, and other sleep disorders with nSOREMP of CCSD. nSOREMP prevalence in NT1 was 33.33% and in NT2, 28.30%. Noteworthy disparities in NT1 included N2 percentages, REM latency, and SOREMPs in Multiple Sleep Latency Test (MSLT). In NT2, differences were significant in age, sleep latency, N2 and REM latencies, arousal index, mean sleep latency in MSLT, and MSLT SOREMPs. CONCLUSIONS: This study highlights the distinct characteristics of nSOREMP in the Chinese population. Patients exhibiting symptoms suggestive of the onset of narcolepsy are advised to undergo an MSLT, irrespective of the occurrence of SOREMP during nocturnal PSG.

Overexpression of SYNGAP1 suppresses the proliferation of rectal adenocarcinoma via Wnt/ß-Catenin signaling pathway.

Rectal adenocarcinoma (READ) is a common malignant tumor of the digestive tract. Growing studies have confirmed Ras GTPase-activating proteins are involved in the progression of several tumors. This study aimed to explore the expression and function of Ras GTPase-activating proteins in READ. In this study, we analyzed RNA sequencing data from 165 patients with READ and 789 normal tissue samples, identifying 5603 differentially expressed genes (DEGs), including 2937 upregulated genes and 2666 downregulated genes. Moreover, we also identified two dysregulated genes, RASA4 and SYNGAP1, among six Ras GTPase-activating proteins. High NF1 expression was associated with longer overall survival, while high SYNGAP1 expression showed a trend towards extended overall survival. Further analysis revealed the mutation frequency and copy number variations of Ras GTPase-activating proteins in various cancer samples. Additionally, DNA methylation analysis demonstrated a negative correlation between DNA methylation of Ras GTPase-activating proteins and their expression. Moreover, among Ras GTPase-activating proteins, we focused on SYNGAP1, and experimental validation confirmed that the overexpression of SYNGAP1 in READ significantly suppressed READ cell proliferation and increased apoptosis via regulating the Wnt/ß-Catenin signaling pathway. These findings underscored the potential significance of SYNGAP1 in READ and provide new insights for further research and treatment.

The causal relationship between gut microbiota and immune skin diseases: A bidirectional Mendelian randomization.

BACKGROUND: Increasing evidence suggests that alterations in gut microbiota are associated with a variety of skin diseases. However, whether this association reflects a causal relationship remains unknown. We aimed to reveal the causal relationship between gut microbiota and skin diseases, including psoriasis, atopic dermatitis, acne, and lichen planus. METHODS: We obtained full genetic association summary data for gut microbiota, psoriasis, atopic dermatitis, acne, and lichen planus from public databases and used three methods, mainly inverse variance weighting, to analyze the causal relationships between gut microbiota and these skin diseases using bidirectional Mendelian randomization, as well as sensitivity and stability analysis of the results using multiple methods. RESULTS: The results showed that there were five associated genera in the psoriasis group, seven associated genera were obtained in the atopic dermatitis group, a total of ten associated genera in the acne group, and four associated genera in the lichen planus group. The results corrected for false discovery rate showed that Eubacteriumfissicatenagroup (P = 2.20E-04, OR = 1.24, 95%CI:1.11-1.40) and psoriasis still showed a causal relationship. In contrast, in the reverse Mendelian randomization results, there was no evidence of an association between these skin diseases and gut microbiota. CONCLUSION: We demonstrated a causal relationship between gut microbiota and immune skin diseases and provide a new therapeutic perspective for the study of immune diseases: targeted modulation of dysregulation of specific bacterial taxa to prevent and treat psoriasis, atopic dermatitis, acne, and lichen planus.

Benzoylaconitine: A promising ACE2-targeted agonist for enhancing cardiac function in heart failure.

Benzoylaconitine is a natural product in the treatment of cardiovascular disease. However, its pharmacological effect, direct target protein, and molecular mechanisms for the treatment of heart failure are unclear. In this study, benzoylaconitine inhibited Ang II-induced cell hypertrophy and fibrosis in rat primary cardiomyocytes and rat fibroblasts, while attenuating cardiac function and cardiac remodeling in TAC mice. Using the limited proteolysis-mass spectrometry (LiP-MS) method, the angiotensin-converting enzyme 2 (ACE2) was confirmed as a direct binding target of benzoylaconitine for the treatment of heart failure. In ACE2-knockdown cells and ACE2-/- mice, benzoylaconitine failed to ameliorate cardiomyocyte hypertrophy, fibrosis, and heart failure. Online RNA-sequence analysis indicated p38/ERK-mediated mitochondrial reactive oxygen species (ROS) and nuclear factor kappa B (NF-κB) activation are the possible downstream molecular mechanisms for the effect of BAC-ACE2 interaction. Further studies in ACE2-knockdown cells and ACE2-/- mice suggested that benzoylaconitine targeted ACE2 to suppress p38/ERK-mediated mitochondrial ROS and NF-κB pathway activation. Our findings suggest that benzoylaconitine is a promising ACE2 agonist in regulating mitochondrial ROS release and inflammation activation to improve cardiac function in the treatment of heart failure.

Multi-omics landscape to decrypt the distinct flavonoid biosynthesis of Scutellaria baicalensis across multiple tissues.

Scutellaria baicalensis Georgi, also known as huang-qin in traditional Chinese medicine, is a widely used herbal remedy due to its anticancer, antivirus, and hepatoprotective properties. The S. baicalensis genome was sequenced many years ago; by contrast, the proteome as the executer of most biological processes of S. baicalensis in the aerial parts, as well as the secondary structure of the roots (xylem, phloem, and periderm), is far less comprehensively characterized. Here we attempt to depict the molecular landscape of the non-model plant S. baicalensis through a multi-omics approach, with the goal of constructing a highly informative and valuable reference dataset. Furthermore, we provide an in-depth characterization dissection to explain the two distinct flavonoid biosynthesis pathways that exist in the aerial parts and root, at the protein and phosphorylated protein levels. Our study provides detailed spatial proteomic and phosphoproteomic information in the context of secondary structures, with implications for the molecular profiling of secondary metabolite biosynthesis in non-model medicinal plants.

The Fitting of the OJ Phase of Chlorophyll Fluorescence Induction Based on an Analytical Solution and Its Application in Urban Heat Island Research.

Chlorophyll (Chl) fluorescence induction (FI) upon a dark-light transition has been widely analyzed to derive information on initial events of energy conversion and electron transfer in photosystem II (PSII). However, currently, there is no analytical solution to the differential equation of QA reduction kinetics, raising a doubt about the fitting of FI by numerical iteration solution. We derived an analytical solution to fit the OJ phase of FI, thereby yielding estimates of three parameters: the functional absorption cross-section of PSII (σPSII), a probability parameter that describes the connectivity among PSII complexes (p), and the rate coefficient for QA- oxidation (kox). We found that σPSII, p, and kox exhibited dynamic changes during the transition from O to J. We postulated that in high excitation light, some other energy dissipation pathways may vastly outcompete against excitation energy transfer from a closed PSII trap to an open PSII, thereby giving the impression that connectivity seemingly does not exist. We also conducted a case study on the urban heat island effect on the heat stability of PSII using our method and showed that higher-temperature-acclimated leaves had a greater σPSII, lower kox, and a tendency of lower p towards more shade-type characteristics.

Ecological transformation is the key to improve ecosystem health for resource-exhausted cities: A case study in China based on future development scenarios.

Numerous cities are currently grappling with the challenge of ecological transformation, especially those categorized as resource-exhausted cities. In these urban areas, land use change is a highly scrutinized issue, as different land use strategies can lead to varied outcomes, impacting the ecological environment in multiple dimensions. Assessing ecosystem health reflects the quality of the regional ecological environment and serves as a comprehensive indicator for evaluating the sustainability and stability of urban ecosystems. To this end, a multi-objective optimization model was constructed to predict land use changes under four future development scenarios (four ecological transformation modes), using Shizuishan City (China), a resource-exhausted city situated in an ecologically fragile area, as an example. The "vigor-organization-resilience" assessment framework was employed to evaluate the ecosystem health conditions in each scenario from three dimensions. The study results showed: (1) The ranking of the average ecological health levels in Shizuishan City for 2022 and different future development scenarios is as follows: Low-Carbon Economic Development Scenario (0.302) > Ecological-Economic Coordinated Development Scenario (0.291) > Baseline Scenario (0.290) > Economic Development Scenario (0.281) > 2022 (0.248). (2) Compared to 2022, the ecosystem health levels under the four ecological transformation modes had all improved, with improvement areas accounting for over 60 %, highlighting the urgent necessity of ecological transformation in Shizuishan City. Among them, the Low-Carbon Economic Development Scenario exhibited the largest improvement area, reaching 75.81 %. (3) Ecological system vitality was identified as the dominant dimension influencing the ecological health in this region. This study emphasized multi-objective development needs and provided an integrated ecosystem health assessment method for assessing the comprehensive ecological effects of future ecological transformation modes in resource-exhausted cities.

An all-glass based micro gas chromatographic column for light hydrocarbon separation with HKUST-1 as stationary phase.

BACKGROUND: The gas chromatography column is one of the key components of the gas chromatograph and typically be miniaturized using micro-electro-mechanical system (MEMS) technology. Due to the limited area of the Si wafer, the column length of micro gas chromatographic column (µGCC) is usually much smaller than that of commercial chromatographic columns. Therefore, it is always difficult to use µGCCs to separate small molecule gas components such as light hydrocarbons. More importantly, the heterogeneous microchannel surface formed by silicon glass bonding causes uneven stationary phase coating, further preventing the improvement of separation performance. RESULTS: In this paper, a novel all-glass based µGCC with 2 m length for the separation of light hydrocarbons is proposed. The microchannels of the µGCC were directly prepared in the glass substrate by ultrafast laser assisted chemical etching (ULAE). The all-glass microchannels make the coating of the hydrophilic metal-organic frameworks (MOFs) stationary phase continuously because of the homogeneous material composition. Therefore, a widely used copper based hydrophilic MOFs HKUST-1 was used as stationary phase for coating and testing. The test results show that the µGCC which is an open tubular column can realize the baseline separation of light hydrocarbons at 100 °C. And the resolution of difficult separated compounds, methane and ethane, can reach 12.98, which is 201.86 % higher than the silica-based monolithic capillary column in the relevant research. The resolution of ethane and ethylene reaches 6.81 at 120 °C. SIGNIFICANCE: The µGCC fabricated by ULAE method is composed of all-glass and has the uniform stationary phase coating because of the homogeneous microchannel surface which greatly improve the separation performance, resulting in a large resolution for methane and ethane. The all-glass µGCC has broad application prospects in light hydrocarbon separation.

The determination of the optimal threshold on measurement of thyroid volume using quantitative SPECT/CT for Graves' hyperthyroidism.

PURPOSE: To investigate the optimal threshold for measuring thyroid volume in patients with Grave's hyperthyroidism (GH) by SPECT/CT. MATERIALS AND METHODS: A 53 mL butterfly-shaped hollow container made of two 45-degree transparent elbows was put into a NEMA IEC phantom tank. The butterfly-shaped container and the tank were then filled with Na99mTcO4 of different radioactive concentrations, respectively, which could simulate thyroid gland with GH by different target-to-background ratios (T/B) (200:1, 600:1, 1000:1). The different T/B of planar imaging and SPECT/CT were acquired by a Discovery NM/CT 670 Pro SPECT/CT. With Thyroid software (Version 4.0) of GE-Xeleris workstation, the region of the thyroid gland in planar imaging was delineated. The thyroid area and average long diameter of both lobes were substituted into the Allen formula to calculate the thyroid volume. The calculation error was compared with the actual volume. Q-Metrix software was used to perform CT-based attenuation correction, scatter correction, resolution recovery. Ordered-subsets expectation maximization was used to reconstruct SPECT data. 20%, 25%, 30%, 40%, 50%, 60% thresholds were selected to automatically delineate the volume of interest and compared with the real volume, which determinated the optimal threshold. We measured the thyroid volume of 40 GH patients using the threshold and compared the volumes obtained by planar imaging and ultrasound three-dimensional. The differences of the volumes with different T/B and thresholds were compared by the ANOVA and least significant difference t test. The volumes delineated by SPECT/CT were evaluated using ANOVA, least significant difference t test, correlation analysis and, linear regression and Bland-Altman concordance test plot. The differences and consistency of thyroid volume were compared among the above three methods. RESULTS: There was no significant difference in the results between different T/B models (P > 0.05). The thyroid volume calculated by the planar imaging formula method was higher than the real volume, with an average overestimation of 22.81%. The volumes delineated by SPECT/CT threshold automatically decreased while the threshold increased. There were significant differences between groups with different thresholds (P < 0.001). With an average error of 3.73%, the thyroid volume analyzed by the threshold of 25% was close to the results of ultrasound measurement (P > 0.05). Thyroid volume measured by planar imaging method was significantly higher than ultrasound and SPECT/CT threshold automatic delineation method (P < 0.05). The agreement between the SPECT/CT 25% threshold and ultrasound (r = 0.956, b = 0.961) was better than that between the planar imaging and ultrasound (r = 0.590, b = 0.574). The Bland-Altman plot also showed that the thyroid volume measured by the 25% threshold automatic delineation method was in good agreement with the ultrasound measurement. CONCLUSIONS: The T/B has no effect on the measurement of thyroid volume in GH patients; planar imaging method can significantly overestimate thyroid volume in GH patients, and 25% threshold automatic delineation method can obtain more accurate thyroid volume in GH patients.

A semi-packed gas chromatographic column with staggered elliptic cylindrical post arrays.

A semi-packed gas chromatographic column has the advantages of high specific surface area and low column pressure. We report that the stagnation regions formed in the adjacent posts along the channel of the semi-packed columns can decrease the area and height of chromatographic peaks, which makes it difficult to detect low-concentration mixed gases. A semi-packed column with staggered elliptic cylindrical post arrays (SC-S) made using a micro-electro-mechanical system technique is presented, and the separation performance of SC-S is compared with that of a semi-packed column with aligned elliptic cylindrical post arrays (SC-A). The simulation results show that the width of stagnation regions in SC-S is 86.89% smaller than that in SC-A. The experimental results indicate that the area and height of chromatographic peaks increased as stagnation regions reduced. In the separation of the alkane mixture from C8 through C10 with 10 ppm concentration, the chromatographic peak of decane was hardly identified in SC-A while the chromatographic peak in SC-S was still clearly visible. The chromatographic peak heights of octane and nonane were increased by 65.06% and 130.00%, respectively, in SC-S. The peak areas of octane and nonane were increased by 120.45% and 168.18%, respectively.

Analysis of telomere length and the relationship with neurocognitive functions in euthymic bipolar disorder: A cross-sectional pilot study.

BACKGROUND: Telomere shortening has been considered a potential biological marker related to disease susceptibility and aging in psychiatric disorders. However, the relationship between telomere length and bipolar disorder (BD-I and BD-II) is uncertain. Moreover, whether telomere shortening is an independent factor of cognitive impairment in BD patients is still inconclusive. METHODS: We explore telomere length and cognitive function in patients with bipolar disorder and the relationship between them. We enrolled three groups (35 patients with euthymic BD-I, 18 with euthymic BD-II, and 38 healthy controls). Telomere length was measured by fluorescent quantitative polymerase chain reaction (q-PCR), and cognitive function was evaluated by the MATRICS Consensus Cognitive Battery (MCCB). SPSS 24.0 was used for statistical analysis. RESULTS: The telomere length of euthymic patients with BD-I and BD-II was shorter than that of healthy controls (F = 8.228, P = 0.001, η2 = 0.176). Telomere length was not significantly different between BD-I and BD-II. Compared to HCs, poor performance was detected in attention and vigilance in BD-I patients (F = 3.473, P = 0.036). Working memory was positively correlated with telomere length in BD-II patients (Beta = 0.5, P = 0.041, Adjusted R2 = 0.2). CONCLUSIONS: The current study provided evidence of shortened telomere length in euthymic BD patients, indicating that telomere shortening might be a promising biomarker of susceptibility to bipolar disorder. The telomere length predicted the working memory in BD-II patients. Further studies are needed to clarify the role of accelerated aging on cognitive functioning in a young group of patients with BD.

Dynamic fecal microenvironment properties enable predictions and understanding of peripartum blood oxidative status and nonesterified fatty acids in dairy cows.

The transition period in dairy cows is a critical stage and peripartum oxidative status, negative energy balance (NEB), and inflammation are highly prevalent. Fecal microbial metabolism is closely associated with blood oxidative status and nonesterified fatty acids (NEFA) levels. Here, we investigated dynamic changes in total oxidative status markers and NEFA in blood, fecal microbiome, and metabolome of 30 dairy cows during transition (-21, -7, +7, +21 d relative to calving). Then the Bayesian network and 9 machine-learning algorithms were applied to dismantle their relationship. Our results show that the oxidative status indicator (OSI) of -21, -7, +7 d was higher than +21 d. The plasma concentration of NEFA peaked on +7 d. For fecal microenvironment, a decline in bacterial α diversity was observed at postpartum and in bacterial interactions at +7 d. Conversely, microbial metabolites involved in carbohydrate, lipid, and energy metabolism increased on +7 d. A correlation analysis revealed that 11 and 10 microbial metabolites contributed to OSI and NEFA variations, respectively (arc strength >0.5). The support vector machine (SVM) radial model showed the highest average predictive accuracy (100% and 88.9% in the test and external data sets) for OSI using 1 metabolite and 3 microbiota. The SVM radial model also showed the highest average diagnostic accuracy (100% and 91% in the test and external data sets) for NEFA with 2 metabolites and 3 microbiota. Our results reveal a relationship between variation in the fecal microenvironment and indicators of oxidative status, NEB, and inflammation, which provide a theoretical basis for the prevention and precise regulation of peripartum oxidative status and NEB.

Breath volatile organic compounds for chronic kidney disease progression monitoring.

Breath analysis may provide a convenient and non-invasive method for clinical monitoring of chronic kidney disease (CKD) progression. However, few breath volatile organic compounds (VOCs) indicating progression of CKD have been reported. In this study, we used gas chromatography-mass spectrometry (GC-MS) for untargeted detection of breath VOCs in stage 1, 3, and 5 CKD patients. The results showed that, the levels of breath 4-heptanone, n-octane, and n-dodecane gradually increased from CKD stage 1 to stage 5, and their increasing rates from CKD stage 3 to stage 5 were higher than those from CKD stage 1 to stage 3. Gender, smoking habits, age, and body mass index (BMI) had insignificant impact on the levels of the three breath VOCs. The accuracies of the polynomial support vector machine (SVM) and K-nearest neighbour (KNN) models based on 4-heptanone + n-octane + n-dodecane combination in distinguishing CKD stages 1, 3, and 5 were 76.3% and 72.8%, respectively. The combination of 4-heptanone + n-octane + n-dodecane was superior to any single component for monitoring CKD progression. These discoveries have valuable implications for long-term clinical monitoring of CKD and improving our understanding of CKD.

Biomechanical characteristics of a novel interspinous distraction fusion device in the treatment of lumbar degenerative diseases: a finite element analysis.

BACKGROUND: A novel interspinous distraction fusion (ISDF) device has been used to treat lumbar degenerative diseases. As a minimally invasive technique, ISDF differs from the traditional interspinous process distraction devices. Currently, biomechanical studies on ISDF are rare. OBJECTIVE: To investigate the biomechanical properties of the ISDF device (BacFuse) which is used to treat lumbar degenerative diseases. METHODS: Three-dimensional L3-L5 models were created. The models were divided into four groups: intact (M1), local decompression alone (M2), internal fixation alone (M3) and local decompression combined with internal fixation (M4), based on different surgical procedures. Local laminectomy was performed to resect the lower part of the L4 lamina and the upper part of the L5 lamina at the right lamina of L4/5 in the M2 and M4 groups. After meshing the models elements, Abaqus were used to perform the finite element (FE) analysis. The intervertebral range of motion (ROM) was measured during flexion, extension, left lateral bending, right lateral bending, left rotation and right rotation under a follower load of 400 N with a 7.5Nm moment. The distributions of disc and facet joint stresses were observed and recorded. Spinal vertebral stress was compared, and internal fixation device stress was observed. RESULTS: The ROM of L4/5 in M2 increased in flexion, extension, left lateral bending, right lateral bending, left rotation and right rotation compared with that in M1. In all motion directions, the ROM at L4/5 decreased, and the ROM at L3/4 increased after implantation of the ISDF device in M3 and M4 groups. The disc stress and facet joint stresses in the instrumented segment decreased after implantation of the ISDF device. The spinous process loaded a certain amount of stress in M3 and M4 groups. The spikes of the internal fixation device were loaded with the maximum stress. CONCLUSION: BacFuse exhibited a reduction in intervertebral ROM, as well as decreased stress on the intervertebral disc and facet joint, while also demonstrating a discernible impact on the upper adjacent segment.

Transcriptome Analysis Reveals the Inhibitory Effect of Cu2+ on Polyferric Sulfate Floc Reduction by Shewanella putrefaciens CN32.

Polyferric sulfate (PFS), an economical coagulant widely used for removing heavy metal contaminants from water, is susceptible to reduction and transformation by iron-reducing bacteria prevalent in sediments. However, the effect of heavy metal ions adsorbed in PFS flocs on this biological process remains unclear. According to our results, compared with other heavy metal cations (e.g., Cu2+, Cd2+, Zn2+, Ni2+, Pb2+, and Co2+), Cu2+ had a stronger inhibitory effect on PFS floc reduction by Shewanella putrefaciens CN32, a typical dissimilatory iron-reducing bacterium. The presence of Cu2+ remarkably influenced the global transcription of CN32, resulting in 782 upregulated genes and 713 downregulated genes that are mainly annotated in energy production, amino acid metabolism, protein biosynthesis, and oxidation‒reduction processes. The anaerobic TCA cycle for energy (electron) production was significantly activated in the presence of Cu2+, while the transcription of many genes related to the extracellular electron transfer pathway was downregulated, which is responsible for the decreased Fe3+ reduction. Moreover, the pathways of assimilatory sulfate reduction and subsequent cysteine biosynthesis were significantly enriched, which is hypothesized to result in the consumption of abundant energy produced from the enhanced anaerobic TCA cycle, revealing a strategy to address the oxidative stress caused by Cu2+. This work elucidates the unusual suppressive effects of Cu2+ on the microbial reduction of PFS flocs, which reveals the high resistance of PFS flocs to microbial destruction when used to treat Cu2+ pollution in water, thus demonstrating their tremendous practical prospects.

[Comparative study of two novel nickel-titanium instruments for root canal preparation in curved canals on shaping ability and microcrack formation].

PURPOSE: To evaluate the shaping ability and microcrack formation of ProTaper Next (PTN) and XP-endo Shaper (XPS) systems in the mesial curved root canals of mandibular molars by using micro-CT scans. METHODS: Sixteen mandibular molars with two independent mesial root canals and curvature ranging from 25° to 35° were randomly divided into two groups. The preparation time was recorded. Pre-and-postoperative images were scanned by micro-CT. The following parameters were evaluated: canal transportation, centering ratio, changes in canal volume, canal/root width ratio and microcrack formation. SPSS 22.0 software package was used to analyze the data. RESULTS: Significant difference (P＜0.05) was found for canal transportation at the section of 1, 3, 5, 7 mm from the apical foramen and centering ratio at the section of 1, 3, 7 mm from the apical foramen, where XPS files were superior. There was no significant difference for centering ratio at the section of 5 mm from the apical foramen(P＞0.05). XPS groups significantly consumed less time during the preparation(P＜0.05). There was no significant difference between the two groups for the increase amount of volume, and canal/root width ratio(P＞0.05). Both instruments did not induce new microcrack after preparation. CONCLUSIONS: PTN and XPS can both shape curved canals effectively and safely. XPS showed better centering ability and reduced preparation time during preparation.

Micro gas chromatographic column with copper benzene-1,3,5-tricarboxylate modified by multilayer fluorinated graphene as a stationary phase.

A composite material was synthesized at room temperature by performing modification of the copper benzene-1,3,5-tricarboxylate (HKUST-1) metal-organic framework material by multilayer fluorinated graphene (FG). The FG-HKUST-1 composite was used as a stationary phase for a micro gas chromatography column (µGCC) fabricated using micro-electro-mechanical system (MEMS) technology. The separation results showed that the µGCC with the FG-HKUST-1 composite stationary phase achieved a baseline separation of C1-C4 in 8 min. The retention factors for C2-C4 were 2.13, 7.14, and 12.04, respectively. The maximum relative standard deviation (RSD) of the retention times was 0.14 %. The difference in the retention time between methane and ethane was 1.11 min, with a resolution of 9.2 for methane and ethane. The retention factor of ethane and the resolution of methane and ethane were increased by 166 % and 114 %. Therefore, this µGCC is promising for separating light hydrocarbons with widely differing concentrations.

DDAH1 Protects against Cardiotoxin-Induced Muscle Injury and Regeneration.

Nitric oxide (NO) is an important biological signaling molecule affecting muscle regeneration. The activity of NO synthase (NOS) is regulated by dimethylarginine dimethylaminohydrolase 1 (DDAH1) through degradation of the endogenous NOS inhibitor asymmetric dimethylarginine (ADMA). To investigate the role of DDAH1 in muscle injury and regeneration, muscle-specific Ddah1-knockout mice (Ddah1MKO) and their littermates (Ddah1f/f) were used to examine the progress of cardiotoxin (CTX)-induced muscle injury and subsequent muscle regeneration. After CTX injection, Ddah1MKO mice developed more severe muscle injury than Ddah1f/f mice. Muscle regeneration was also delayed in Ddah1MKO mice on Day 5 after CTX injection. These phenomena were associated with higher serum ADMA and LDH levels as well as a great induction of inflammatory response, oxidative stress and cell apoptosis in the gastrocnemius (GA) muscle of Ddah1MKO mice. In the GA muscle of CTX-treated mice, Ddah1 deficiency decreased the protein expression of M-cadherin, myogenin, Bcl-2, peroxiredoxin 3 (PRDX3) and PRDX5, and increased the protein expression of MyoD, TNFα, Il-6, iNOS and Bax. In summary, our data suggest that DDAH1 exerts a protective role in muscle injury and regeneration.