[Prognostic nutritional index application value for acute-on-chronic liver failure co-infection]

Objective: To explore the predictive value of the prognostic nutritional index (PNI) in concurrently infected patients with acute-on-chronic liver failure (ACLF). Methods: 220 cases with ACLF diagnosed and treated at the First Affiliated Hospital of Xi'an Jiaotong University from January 2011 to December 2016 were selected. Patients were divided into an infection and non-infection group according to whether they had co-infections during the course of the disease. Clinical data differences were compared between the two groups of patients. Binary logistic regression analysis was used to screen out influencing factors related to co-infection. The receiver operating characteristic curve was used to evaluate the predictive value of PNI for ACLF co-infection. The measurement data between groups were compared using the independent sample t-test and the Mann-Whitney U rank sum test. The enumeration data were analyzed using the Fisher exact probability test or the Pearson χ(2) test. The Pearson method was performed for correlation analysis. The independent risk factors for liver failure associated with co-infection were analyzed by multivariate logistic analysis. Results: There were statistically significant differences in ascites, hepatorenal syndrome, PNI score, and albumin between the infection and the non-infection group (P < 0.05). Among the 220 ACLF cases, 158 (71.82%) were infected with the hepatitis B virus (HBV). The incidence rate of infection during hospitalization was 69.09% (152/220). The common sites of infection were intraabdominal (57.07%) and pulmonary infection (29.29%). Pearson correlation analysis showed that PNI and MELD-Na were negatively correlated (r = -0.150, P < 0.05). Multivariate logistic analysis results showed that low PNI score (OR=0.916, 95%CI: 0.865~0.970), ascites (OR=4.243, 95%CI: 2.237~8.047), and hepatorenal syndrome (OR=4.082, 95%CI : 1.106~15.067) were risk factors for ACLF co-infection (P < 0.05). The ROC results showed that the PNI curve area (0.648) was higher than the MELD-Na score curve area (0.610, P < 0.05). The effectiveness of predicting infection risk when PNI was combined with ascites and hepatorenal syndrome complications was raised. Patients with co-infections had a good predictive effect when PNI ≤ 40.625. The sensitivity and specificity were 84.2% and 41.2%, respectively. Conclusion: Low PNI score and ACLF co-infection have a close correlation. Therefore, PNI has a certain appraisal value for ACLF co-infection.

From Monomers to Hexamers: A Theoretical Probability of the Neighbor Density Approach to Dissect Protein Oligomerization in Cells

Deciphering the oligomeric state of proteins within cells is pivotal to understanding their role in intricate cellular processes. With the recent advances in single-molecule localization microscopy, previous efforts have harnessed protein location density approaches, coupled with simulations, to extract membrane protein oligomeric states in cells, highlighting the value of such techniques. However, a comprehensive theoretical approach that can be universally applied across different proteins (e.g., membrane and cytosolic proteins) remains elusive. Here, we introduce the theoretical probability of neighbor density (PND) as a robust tool to discern protein oligomeric states in cellular environments. Utilizing our approach, the theoretical PND was validated against simulated data for both membrane and cytosolic proteins, consistently aligning with experimental baselines for membrane proteins. This congruence was maintained even when adjusting for protein concentrations or exploring proteins of various oligomeric states. The strength of our method lies not only in its precision but also in its adaptability, accommodating diverse cellular protein scenarios without compromising the accuracy. The development and validation of the theoretical PND facilitate accurate protein oligomeric state determination and bolster our understanding of protein-mediated cellular functions.

Variations in Intracellular Organometallic Reaction Frequency Captured by Single-Molecule Fluorescence Microscopy

Studies of organometallic reactions in living cells commonly rely on ensemble-averaged measurements, which can obscure the detection of reaction dynamics or location-specific behavior. This information is necessary to guide the design of bioorthogonal catalysts with improved biocompatibility, activity, and selectivity. By leveraging the high spatial and temporal resolution of single-molecule fluorescence microscopy, we have successfully captured single-molecule events promoted by Ru complexes inside live A549 human lung cells. By observing individual allylcarbamate cleavage reactions in real-time, our results revealed that they occur with greater frequency inside the mitochondria than in the non-mitochondria regions. The estimated turnover frequency of the Ru complexes was at least 3-fold higher in the former than the latter. These results suggest that organelle specificity is a critical factor to consider in intracellular catalyst design, such as in developing metallodrugs for therapeutic applications.

Probing Oxidant Effects on Superoxide Dismutase 1 Oligomeric States in Live Cells Using Single-Molecule Fluorescence Anisotropy

The protein Cu/Zn superoxide dismutase (SOD1) is known to function as a dimer, but its concentration in cells (∼50 μM) and the dimerization constant (K d of 500 μM) results suggest that it exists in a monomer-dimer equilibrium. It is unclear how the oligomeric state of SOD1 changes when cells are initially exposed to high levels of extracellular oxidative stress. To address this problem, we introduced the single-molecule fluorescence anisotropy (smFA) assay to explore SOD1 oligomeric states in live COS7 cells. smFA specifically probes the fluorescence polarization changes caused by molecular rotations where the fast-rotating molecules (either due to smaller hydrodynamic volume or less viscous environments) deteriorate the emission polarization and thus lower the anisotropy. After validating that smFA is effective in distinguishing monomeric and dimeric fluorescence proteins, we overexpressed SOD1 in live COS7 cells and investigated how its oligomeric state changes under basal, 2 h, and 24 h 100 μM H2O2 treatments. We found that treating cells with H2O2 promotes SOD1 dimerization and decreases cellular viscosity in 2 h. Interestingly, prolonged H2O2 treatments show similar results as the basal conditions, indicating that cells return to a steady state similar to the basal state after 24 h, despite the presence of H2O2. Our results demonstrate that SOD1 changes its oligomeric state equilibrium in response to extracellular oxidative stresses. smFA will open new opportunities to explore the relationship between the SOD1 oligomer state and its H2O2-based signaling and transcription regulation roles.

[Diffuse midline glioma with H3K27 alteration in adults: a clinicopathological analysis]

Objective: To investigate the clinicopathological characteristics, pathological diagnosis and prognosis of diffuse midline glioma (DMG) with H3K27 alteration in adults. Methods: Twenty cases of H3K27-altered adult DMG diagnosed in the First Affiliated Hospital of Nanjing Medical University were enrolled from 2017 to 2022. All cases were evaluated by clinical and imaging presentations, HE, immunohistochemical staining and molecular genetics; and the relevant literature was reviewed. Results: The ratio of male to female was 1∶1, and the median age was 53 years (range from 25 to 74 years); the tumors were located in the brainstem (3/20, 15%) and non-brainstem (17/20, 85%; three in thoracolumbar spinal cord and one in pineal region). The clinical manifestations were non-specific, mostly dizziness, headache, blurred vision, memory loss, low back pain, limb sensation and/or movement disorders, etc. Microscopically, the tumors showed infiltrative growth, with WHO grade 2 (3 cases), grade 3 (12 cases), and grade 4 (5 cases). The tumors showed astrocytoma-like and oligdendroglioma-like, pilocytic astrocytoma-like and epithelioid-like patterns. Immunohistochemically, the tumor cells were positive for GFAP, Olig2 and H3K27M, and H3K27me3 expression was variably lost. ATRX expression was lost in four cases, p53 was strongly positive in 11 cases. Ki-67 index was about 5%-70%. Molecular genetics showed p. k27m mutation in exon 1 of H3F3A gene in 20 cases; BRAF mutation in two cases: V600E and L597Q mutation in one case each. Follow up intervals ranged from 1 to 58 months, and the survival time for brainstem (6.0 months) and non-brainstem (30.4 months) tumors was significantly different (P<0.05). Conclusions: DMG with H3K27 alteration is uncommonly found in adults, mostly occurs in non-brainstem, and can present in adults of all ages. Owing to the wide histomorphologic features, mainly astrocytic differentiation, routine detection of H3K27me3 in midline glioma is recommended. Molecular testing should be performed on any suspected cases to avoid missed diagnosis. Concomitant BRAF L597Q mutation and PPM1D mutation are novel findings. The overall prognosis of this tumor is poor, with tumors located in the brainstem showing worse outcome.

[Clinical application of a quantitative method of atlantoaxial reduction angle in basilar invagination]

Objectives: To investigate the clinical application effect of a quantitative method of atlantoaxial reduction angle in basilar invagination. Methods: A retrospective analysis of clinical and radiographic data was conducted of 38 patients with complicated atlantoaxial dislocation and basilar invagination admitted to the Department of Neurosurgery, First Affiliated Hospital of Chongqing Medical University from May 2020 to May 2022. There were 5 males and 33 females, aged (53.5±9.9) years (range: 38 to 80 years). All patients underwent C_1-2 interarticular fusion cage implantation+occipital-cervical fixation by pressing rob with the cantilever technique. The atlantoaxial reduction model of previous studies by our team was used to calculate the reduction angles before surgery. Then titanium rods of prebending angle were prepared according to the calculation before the operation. After that quantitative reduction of angle was performed during the operation. The paired t-test was used to compare the difference between the theoretical and actual reset value. Results: The theoretical reduction angle of all patients was (10.62±1.78)° (range: 6.40° to 13.20°), the actual reduction angle was (10.53±1.63)° (range: 6.70° to 13.30°) and there was no statistical difference between them (t=1.688, P=0.100). The theoretical posterior occipitocervical angle after the operation of all patients was (117.37±5.88)° (range: 107.00° to 133.00°), the actual posterior occipitocervical angle after the operation was (118.25±6.77)° (range: 105.40° to 135.80°) and there was no statistical difference between them (t=-0.737, P=0.466). The postoperative follow-up time of the patients was more than 6 months and the symptoms of all patients were relieved. All patients had satisfactory fusion between small joints without incision infection, internal fixation fracture, displacement, atlantoaxial redislocation, and other long-term complications. Conclusion: The quantitative method of atlantoaxial reduction angle in basilar invagination can calculate the theoretical reduction angle of the clivus axis angle and guide the preparation of the pre-bending titanium rod before surgery, so as to realize the quantification of the atlantoaxial reduction angle.

FDX1-dependent and independent mechanisms of elesclomol-mediated intracellular copper delivery

Recent studies have uncovered the therapeutic potential of elesclomol (ES), a copper-ionophore, for copper deficiency disorders. However, we currently do not understand the mechanism by which copper brought into cells as ES-Cu(II) is released and delivered to cuproenzymes present in different subcellular compartments. Here, we have utilized a combination of genetic, biochemical, and cell-biological approaches to demonstrate that intracellular release of copper from ES occurs inside and outside of mitochondria. The mitochondrial matrix reductase, FDX1, catalyzes the reduction of ES-Cu(II) to Cu(I), releasing it into mitochondria where it is bioavailable for the metalation of mitochondrial cuproenzyme- cytochrome c oxidase. Consistently, ES fails to rescue cytochrome c oxidase abundance and activity in copper-deficient cells lacking FDX1. In the absence of FDX1, the ES-dependent increase in cellular copper is attenuated but not abolished. Thus, ES-mediated copper delivery to nonmitochondrial cuproproteins continues even in the absence of FDX1, suggesting alternate mechanism(s) of copper release. Importantly, we demonstrate that this mechanism of copper transport by ES is distinct from other clinically used copper-transporting drugs. Our study uncovers a unique mode of intracellular copper delivery by ES and may further aid in repurposing this anticancer drug for copper deficiency disorders.

Subcellular redox responses reveal different Cu-dependent antioxidant defenses between mitochondria and cytosol

Excess intracellular Cu perturbs cellular redox balance and thus causes diseases. However, the relationship between cellular redox status and Cu homeostasis and how such an interplay is coordinated within cellular compartments has not yet been well established. Using combined approaches of organelle-specific redox sensor Grx1-roGFP2 and non-targeted proteomics, we investigate the real-time Cu-dependent antioxidant defenses of mitochondria and cytosol in live HEK293 cells. The Cu-dependent real-time imaging experiments show that CuCl2 treatment results in increased oxidative stress in both cytosol and mitochondria. In contrast, subsequent excess Cu removal by bathocuproine sulfonate, a Cu chelating reagent, lowers oxidative stress in mitochondria but causes even higher oxidative stress in the cytosol. The proteomic data reveal that several mitochondrial proteins, but not cytosolic ones, undergo significant abundance change under Cu treatments. The proteomic analysis also shows that proteins with significant changes are related to mitochondrial oxidative phosphorylation and glutathione synthesis. The differences in redox behaviors and protein profiles in different cellular compartments reveal distinct mitochondrial and cytosolic response mechanisms upon Cu-induced oxidative stress. These findings provide insights into how redox and Cu homeostasis interplay by modulating specific protein expressions at the subcellular levels, shedding light on understanding the effects of Cu-induced redox misregulation on the diseases.

Resolved rotation-vibration non-equilibrium with rotational VIPA-CARS

Simultaneous rotational and vibrational temperatures are measured in an N₂ plasma with rotational coherent anti-Stokes Raman scattering (CARS) resolved with a virtually imaged phased array (VIPA)-based spectrometer. A VIPA spectrally separates rotational transitions for each vibrational state, allowing vibrational populations to be directly measured. VIPA-CARS is shown to provide more accurate measurements of non-equilibrium temperatures than grating-resolved rotational CARS. The general characteristics, limitations, and potential uses of VIPA-CARS are discussed.

[The effect of maternal HBV DNA levels on HBV intrauterine transmission and fetal distress]

Aim: To identify the key risk factors of intrauterine hepatitis B virus transmission (HBV) and its effect on the placenta and fetus. Methods: 425 infants born to hepatitis B surface antigen (HBsAg)-positive pregnant women who received combined immunization with hepatitis B immunoglobulin and hepatitis B vaccine between 2009 to 2015 were prospectively enrolled in this study. The intrauterine transmission situation was assessed by dynamic monitoring of infants HBV DNA load and quantitative HBsAg. Univariate and multivariate regression analysis was used to determine the high risk factors for intrauterine transmission. Stratified analysis was used to determine the relationship between maternal HBV DNA load and fetal distress. Transmission electron microscopy was used to observe HBV Effects on placental tissue. Results: HBV intrauterine infection rate was 2.6% (11/425). Multivariate analysis result showed that the maternal HBV DNA load was an independent risk factor for intrauterine infection among infants (P=0.011). Intrauterine infection and distress rate was significantly higher in infants with with maternal HBV DNA>10⁶ IU/ml than those with HBV DNA <10⁶ IU/ml (12.2% vs. 1.8%; χ²=11.275, P=0.006), and (24.4% vs. 16.0%, χ²=3.993, P=0.046). Transmission electron microscopy showed that mitochondrial edema, endoplasmic reticulum expansion and thicker basement membrane were apparent when the maternal HBV DNA>10⁶ IU/ml than that of maternal HBV DNA<10⁶ IU/ml (960 nm vs. 214 nm, Z=-2.782, P=0.005) in the placental tissue. Conclusion: Maternal HBV DNA>10⁶ IU/ml is associated not only with intrauterine infection, but also with increased incidence of intrauterine distress and placental sub-microstructural changes, providing strong clinical and histological evidence for pregnancy avoidance and treatment in this population.

Generation of a homozygous knock-in human embryonic stem cell line expressing mEos4b-tagged CTR1

Copper transporter 1 (CTR1) is the major membrane protein responsible for cellular copper (Cu) uptake and mediates cellular copper homeostasis. To elucidate CTR1's behavior using imaging approaches, we generated a homozygous knock-in human embryonic stem cell (hESC) clone expressing photoconvertible fluorescence protein mEos4b-tagged endogenous CTR1 using CRISPR-Cas9 mediated homologous recombination. The engineered cells express functional CTR1-mEos4b fusion and have normal stem cell morphology. They remain pluripotent and can be differentiated into all three germ layers in vitro. This resource allows the study of CTR1 at an endogenous level in different cellular contexts using microscopy.

Crossroads between membrane trafficking machinery and copper homeostasis in the nerve system

Imbalanced copper homeostasis and perturbation of membrane trafficking are two common symptoms that have been associated with the pathogenesis of neurodegenerative and neurodevelopmental diseases. Accumulating evidence from biophysical, cellular and in vivo studies suggest that membrane trafficking orchestrates both copper homeostasis and neural functions-however, a systematic review of how copper homeostasis and membrane trafficking interplays in neurons remains lacking. Here, we summarize current knowledge of the general trafficking itineraries for copper transporters and highlight several critical membrane trafficking regulators in maintaining copper homeostasis. We discuss how membrane trafficking regulators may alter copper transporter distribution in different membrane compartments to regulate intracellular copper homeostasis. Using Parkinson's disease and MEDNIK as examples, we further elaborate how misregulated trafficking regulators may interplay parallelly or synergistically with copper dyshomeostasis in devastating pathogenesis in neurodegenerative diseases. Finally, we explore multiple unsolved questions and highlight the existing challenges to understand how copper homeostasis is modulated through membrane trafficking.

A web-based self-management program to improve lifestyle and blood pressure control in patients with primary hypertension: a randomized controlled trial

Background

Hypertension contributes to the main risk factor of the high incidence of cardiovascular diseases and mortality. Successful control of blood pressure requires behavioral changes; therefore, it is of considerable importance to develop a web-based self-management program that assist patients to tailor their lifestyle and empower them manage their disease.

Objective

Our primary aims were to evaluate the effects of a web-based self-management program for improving blood pressure and blood lipids control in patients with primary hypertension. Our secondary aims were to evaluate the effects of the web-based self-management program on enhancing patients' lifestyle, medication adherence and self-efficacy.

Methods

This randomized controlled trial used permuted block randomization design and randomly divided the 222 patients into the intervention group (n=111) and control group (n=111). Patients in the intervention group received the web-based self-management program, and the control group received standard care. Lifestyle and medication adherence were assessed by using the Hypertension Self-Care Activity Level Effects Scale (H-SCALE). Self-efficacy was measured through using the Chinese version of the Self-Efficacy for Managing Chronic Disease 6-Item Scale (SES6C). The data of blood pressure and serum lipids were collected through web-based self-report and chart review. We used the generalized estimating equations to evaluate the effects of the intervention.

Results

There were no statistically significant differences of the baseline demographic characteristics and antihypertensive dosages from both groups. The intervention group received the web-based self-management program and showed a decrease in systolic blood pressures (−19.82 mmHg vs 7.99 mmHg, p&lt;0.001) and diastolic blood pressures at 6 months (−9.17 mmHg vs 0.48 mmHg, p&lt;0.001) compared to the control group. Regarding the H-SCALE scores measured at 6 months, the intervention group achieved a higher Medication Adherence Subscale scores (p&lt;0.001), Diet Subscale scores (p&lt;0.001), and Weight Management Subscale scores (p&lt;0.001) than those of the control group. The intervention group achieved a higher SES6C scores than that of the control group (p&lt;0.001) at 6 months. Finally, the intervention group had significantly lower serum levels of triglycerides and low-density lipoproteins than the control group at 6 months (−11.38 mg/dL vs 16.31 mg/dL, −9.93 mg/dL vs 3.12 mg/dL, respectively, p&lt;0.001).

Conclusion

The greatest benefit of this program was allowing participants to consult dietary issues with us immediately. Since lifestyles vary among different individuals, we considered the individuality of each participant when providing feedback and involving them in the devising of interventions to increase their confidence in hypertension self-care and ultimately achieve the optimal control of blood pressure and blood lipid levels.

Funding Acknowledgement

Type of funding sources: None.

Generation of a homozygous knock-in human embryonic stem cell line expressing SNAP-tagged SOD1

Superoxide Dismutase 1 (SOD1) is an antioxidant enzyme that protects the cells from radical oxygen species. To study the behavior of endogenous SOD1 under a microscope, we genetically modified H1 human embryonic stem cells (hESCs) to express SOD1 fused with a SNAP-tag, a protein tag that can be covalently labeled with a variety of synthetic probes. The engineered homozygous clone expressing SOD1-SNAP fusion proteins has normal stem cell morphology and karyotype, expresses pluripotency markers, and can be differentiated into all three germ layers in vitro, providing a versatile platform for imaging-based studies of SOD1.

Single-molecule microscopy for in-cell quantification of protein oligomeric stoichiometry

Protein organization modification plays a vital role in initiating signaling pathways, transcriptional regulation, and cell apoptosis regulation. Simultaneous quantification of oligomeric state and cellular parameters in the same cell, even though challenging, is required to understand their correlation at the molecular level. Recent advances of fluorescence protein and single-molecule localization microscopy enables the determination of localizations and oligomeric states of target proteins in cells. We reviewed the fluorescence intensity-based, localization-based, and photophysical property-based approaches for in-cell quantification of protein oligomeric stoichiometry. We discussed their working principles, applications, advantages, and limitations. These results also imply the combination of methodologies targeting different biological parameters at the single-cell level is essential to uncover the structure-function relationship at the molecular level.

Dissection of Interaction Kinetics through Single-Molecule Interaction Simulation

The ability to extract kinetic interaction parameters from single-molecule fluorescence resonance energy transfer trajectories without the need for solving complex single-molecule differential equations has the potential to address some of the critical biophysical questions. Here, we provide a noise-free single-molecule interaction simulation (SMIS) tool to give the expected dwell-time distributions and relative populations of each FRET level based on the assigned kinetic model and to dissect kinetic interaction parameters from single-molecule FRET trajectories. The method provides the expected dwell-time distributions, average transition rates, and relative populations of each FRET level based on the assigned kinetic model. By comparing with ground truth data and experimental data, we demonstrated that SMIS is useful to quantify the interaction kinetic rate constants without using the traditional single-molecule analytical solution approach.

[Molecular epidemiological characteristics of methicillin-resistant Staphylococcus aureus during 2017-2018 at a hospital in Shanghai]

Objective: To identify the epidemic clones of MRSA isolates at a hospital in shanghai. Methods: A total of 72 MRSA isolates have been isolated from a second grade hospital between 2017 and 2018, including 32 CA-MRSA isolates, 13 HA-MRSA isolates and 26 MRSA isolates from environment. In this study, MLST and PFGE typing methods were used to analyze the molecular epidemiology of the MRSA isolates. Results: A total of 72 MRSA isolates have been obtained including 46 isolates from clinical specimens, 26 isolates from environments. The 46 MRSA isolates from clinical specimens consisted of 33 CA-MRSA (community-acquired MRSA) and 13 HA-MRSA (hospital-acquired MRSA). Furthermore, these patients infected with MRSA isolates were mostly distributed in the department of geriatrics (34.8%, 16/46), internal medicine (26.1%, 12/46) and surgery (26.1%, 12/46). MLST typing results showed that ST764 was predominant in isolates from both clinical specimens and hospital environments. Furthermore, PFGE typing results showed that most ST764 MRSA had high homolog (>90%). Conclusion: ST764 MRSA isolates might spread in community, hospital and environments. Therefore, continuous monitoring of MRSA and its variation may be useful in understanding the involvement of epidemic clone, and in searching new strategies to control MRSA infection.

Prevention of Postdental Procedure Bacteremia: A Network Meta-analysis

Postdental procedure bacteremia is common and troublesome. The comparative efficacy of multiple prophylactic interventions is unclear. We compared the efficacy of interventions for the prevention of postdental procedure bacteremia. We conducted a review of ClinicalKey, Cochrane CENTRAL, Embase, ProQuest, PubMed, ScienceDirect, Web of Science, and ClinicalTrials.gov from inception to December 4, 2018. Randomized controlled trials that evaluated prophylactic interventions for the prevention of postdental procedure bacteremia were eligible. The primary outcome was the incidence of postdental procedure bacteremia. A total of 24 trials were included with 2,147 participants. Our network meta-analysis demonstrated that intravenous administration of 1,000/200 mg of amoxicillin/clavulanate provided the least incidence of postdental procedure bacteremia among all the prophylactic interventions (odds ratio = 0.03, 95% CI = 0.00 to 0.63) as compared with the placebo/controls. Oral 3 g of amoxicillin had the least incidence of postdental procedure bacteremia among all oral or topical forms of prophylactic interventions (odds ratio = 0.10, 95% CI = 0.02 to 0.44) as compared with the placebo/controls. No serious adverse events, such as anaphylactic shock, mortality, and the development of antibiotic-resistant bacteria, were reported. None of the included subjects were of high risk of infectious endocarditis. Our network meta-analysis demonstrates that intravenous amoxicillin/clavulanate and oral amoxicillin might be the best prophylactic interventions in preventing postdental procedure bacteremia among all the oral/topical forms of interventions for the overall populations.

[Predictive value of single nucleotide polymorphisms of HLA-C and UBE2L3 in evaluating the effect of telbivudine antiviral therapy during pregnancy]

Objective: To investigate the association between single nucleotide polymorphisms (SNPs) of rs3130542 and rs4821116 in the HLA-C and UBE2L3 genes and the effect of telbivudine antiviral therapy during pregnancy in HBeAg-positive mothers through a large-sample control study, and to provide a basis for the development of individualized blocking strategies for pregnant women with a high viral load. Methods: The genotypes of rs3130542 and rs4821116 were determined for 312 pregnant women with a high viral load who received telbivudine antiviral therapy during the second or third trimester of pregnancy, and the dominant model, recessive model, and additive model were used to analyze the association between the genotypes of these two loci and the reduction in HBV DNA load. The Shapiro-Wilk test and the Levene test were used to evaluate data normality and homogeneity of variances, and the t-test or the non-parametric Mann-Whitney U test was selected based on data type and was used for the comparison of means between groups. The Hardy-Weinberg equilibrium was used to determine the genotype of SNPs, and the dominant model, recessive model, and additive model were used for analysis. Results: Mothers with an AA/AG genotype of rs3130542 in the HLA-C gene had a significantly higher probability of HBV DNA load ≥10(3) IU/ml at the time of delivery (P < 0.05) and a significantly higher risk of failure in the prevention of mother-to-child transmission, no matter whether they started to take telbivudine at week 24 or 28 of pregnancy. The association between the genotype of rs4821116 in the UBE2L3 gene and the reduction in viral load in pregnant women needed to be confirmed by studies with a larger sample size. Conclusion: Pregnant women with a high viral load and an AA/AG genotype of rs3130542 in the HLA-C gene tend to have poor response to antiviral therapy during pregnancy, and early antiviral intervention is recommended for such patients.

Quantifying the Oligomeric States of Membrane Proteins in Cells through Super-Resolution Localizations

Transitions between different oligomeric states of membrane proteins are essential for proper cellular functions. However, the quantification of their oligomeric states in cells is technically challenging. Here we developed a new method to quantify oligomeric state(s) of highly expressed membrane proteins using the probability density function of molecule density ( PDF_MD) calculated from super-resolution localizations. We provided the theoretical model of PDF_MD, discussed the effects of protein concentration, cell geometry, and photophysics of fluorescent proteins on PDF_MD, and provided experimental criteria for proper quantification of oligomeric states. This method was further validated using simulated single-molecule fluorescent movies and applied to two membrane proteins, UhpT and SbmA in E. coli. The study shows that PDF_MD is useful in quantifying oligomeric states of membrane proteins in cells that can help in understanding cellular tasks. Potential applications to proteins with higher oligomeric states under high concentration and limitations of our methodology were also discussed.

Imaging Validation of Drug-Eluting Beads Transarterial Chemoembolization of Hepatocellular Carcinomas in Living Donor Liver Transplantation

OBJECTIVE

The aim of this study is to determine whether post-transarterial chemoembolization imaging (computed tomography or magnetic resonance imaging) could accurately predict the tumors' necrosis on pathologic specimens.

BACKGROUND

Transarterial chemoembolization with drug-eluting beads has been proven to be an effective way to bridge patients with hepatocellular carcinomas to liver transplantation.

MATERIALS AND METHODS

From September 2012 to June 2017, 59 patients with a total of 78 hepatocellular carcinomas, who received transarterial chemoembolization with drug-eluting beads before liver transplantation in Kaohsiung Chang Gung Memorial Hospital, were included in the study. All patients and hepatocellular carcinomas have pre-transarterial chemoembolization and post-transarterial chemoembolization images (computed tomography or magnetic resonance imaging) and pathological findings for correlation. Tumor response was evaluated according to modified Response Evaluation Criteria in Solid Tumors. The ranges of necrotic percentage are 100%, 91-99%, 51-90%, and <50%.

RESULTS

The accuracy rate between the imaging and pathology correlation was 40% for computed tomography and 42% for magnetic resonance imaging. The recurrent rate of the complete respond group is 11.5%, the partial respond group is 16.0%, and the stationary group is 28.6%.

CONCLUSION

Computed tomography and magnetic resonance imaging sensitivity is not satisfactory for microscopic evaluation of residual tumors after transarterial chemoembolization with drug-eluting beads. However, survival is good after liver transplantation no matter what the microscopic findings were.

[Primary prevention by hepatitis B vaccine on liver cancer in high incidence area of China]

Objective: Incidence of primary liver cancer (PLC) in China is mostly related to chronic infection of hepatitis B virus (HBV). Qidong was one of the endemic areas with high incidence of PLC in China before 2000. We conducted a series of studies regarding on PLC etiological prevention during the past decades to develop better primary prevention strategies for PLC. Methods: Qidong Hepatitis B Intervention Study was conducted in 1983-1990. A total of 41 182 newborns were randomly assigned to vaccination group and 40 211 (97.64%) of them completed the three-dose, 5 µg-plasma-derived hepatitis B (HB) vaccination series at age 0, 1, 6 month. Among them, 28 988 participants received one-dose 10 µg recombinant HB booster vaccination at age 10-14 years. A total of 41 730 newborns were randomly assigned to the control group. When they were at age 10-14 years, 23 368 participants received the catch-up vaccination with three-dose, 10 µg-recombinant HB vaccine. Two cross-sectional HBV serology surveys were conducted in 1996-2000 and 2008-2012. Information on PLC incidence and mortality of chronic liver diseases were collected through cancer registry and vital statistics until December 31, 2016. Cox proportional hazard models were employed to compute hazard ratio (HR) of PLC and other liver diseases for the participants with neonatal HB vaccination or catch-up vaccination, and the protective efficacy was also calculated. Results: During serologic survey in 1996-2000, a total of 22 689 participants in vaccination group and 12 395 participants in control group donated blood samples. The HBsAg seropositive rates in the vaccination group was 2.16% (491/22 689), which is significantly lower than that of control group (9.08%, 1 126/12 395) (χ²=896.61, P<0.001). During serologic survey in 2008-2012, a total of 17 386 participants in vaccination group and 18 060 participants in control group donated blood samples. The HBsAg seropositive rates in the vaccination group was 1.83% (319/17 386), which is still significantly lower than that of control group (6.77%,1 222/18 060) (χ²=518.05, P<0.001). By December 31, 2016, 4 cases of PLC in the vaccination group and 17 cases of PLC were identified in the vaccination and control group, respectively. The estimated efficacy of neonatal HB vaccination on HBsAg seroprevalence in childhood (at age 10-11 years), early adulthood (at age 19-28 years) and incidence rate of PLC at age below 33 years was 79% (95%CI: 76%-81%), 74% (95%CI: 71%-78%) and 79% (95%CI: 36%-93%), respectively. The estimated efficacy of three-dose, 10 µg-recombinant HB catch-up vaccination in early adulthood is 21% (95%CI: 11%-30%), which is significantly lower than that of neonatal HB vaccination. Conclusion: HB vaccination to neonates/infants is crucial against chronic HBV infection in childhood through young adulthood, and subsequently reduced the risk of PLC in young adults.

Facilitated Unbinding via Multivalency-Enabled Ternary Complexes: New Paradigm for Protein-DNA Interactions

Dynamic protein-DNA interactions constitute highly robust cellular machineries to fulfill cellular functions. A vast number of studies have focused on how DNA-binding proteins search for and interact with their target DNA segments and on what cellular cues can regulate protein binding, for which protein concentration is a most obvious one. In contrast, how protein unbinding could be regulated by protein concentration has evaded attention because protein unbinding from DNA is typically a unimolecular reaction and thus concentration independent. Recent single-molecule studies from multiple research groups have uncovered that protein concentration can facilitate the unbinding of DNA-bound proteins, revealing regulation of protein unbinding as another mechanistic paradigm for gene regulation. In this Account, we review these recent in vitro and in vivo single-molecule experiments that uncovered the concentration-facilitated protein unbinding by multiple types of DNA-binding proteins, including sequence-nonspecific DNA-binding proteins (e.g., nucleoid-associated proteins, NAP), sequence-specific DNA-binding proteins (e.g., metal-responsive transcription regulators CueR and ZntR), sequence-neutral single-stranded DNA-binding proteins (e.g., Replication protein A, RPA), and DNA polymerases. For the in vitro experiments, Marko's group investigated the exchange of GFP-tagged DNA-bound NAPs with nontagged NAPs in solution of increasing concentration using single-molecule magnetic-tweezers fluorescence microscopy. The faster fluorescence intensity decrease with higher nontagged NAP concentrations suggests that DNA-bound NAPs undergo faster exchange with higher free NAP concentrations. Chen's group used single-molecule fluorescence resonance energy transfer measurements to study the unbinding of CueR from its cognate oligomeric DNA. The average microscopic dwell times of DNA-bound states become shorter with increasing CueR concentrations in the surroundings, demonstrating that free CueR proteins can facilitate the unbinding of the incumbent one on DNA through either assisted dissociation or direct substitution. Greene's group studied the unbinding of RPAs from single-stranded DNA using total internal reflection fluorescence microscopy and DNA curtain techniques. The fluorescence intensity versus time traces show faster decay with higher wild-type RPA concentrations, indicating that DNA-bound RPAs can undergo a concentration-facilitated exchange when encountering excess free RPA. van Oijen's group investigated the leading/lagging-strand polymerase exchange events in the bacteriophage T7 and E. coli replication systems using a combination of single-molecule fluorescence microscopy and DNA-flow-stretching assay. The processivity was observed to have larger decrease when the concentration of the Y526F polymerase mutant increases, indicating that the unbinding of the polymerase is also concentration-dependent. Using stroboscopic imaging and single-molecule tracking, Chen's group further advanced their study into living bacterial cells. They found CueR, as well as its homologue ZntR, shows concentration-enhanced unbinding from its DNA-binding site in vivo. Mechanistic consensus has emerged from these in vitro and in vivo single-molecule studies that encompass a range of proteins with distinct biological functions. It involves multivalent contacts between protein and DNA. The multivalency enables the formation of ternary complexes as intermediates, which subsequently give rise to concentration-enhanced protein unbinding. As multivalent contacts are ubiquitous among DNA-interacting proteins, this multivalency-enabled facilitated unbinding mechanism thus provides a potentially general mechanistic paradigm in regulating protein-DNA interactions.

Safety and efficacy of sofosbuvir-based treatment of acute hepatitis C in end-stage renal disease patients undergoing haemodialysis

BACKGROUND

Hepatitis C virus (HCV) infection in patients undergoing haemodialysis is prevalent and aggressive. The treatment of chronic hepatitis C has been revolutionised by the advent of direct-acting antivirals (DAAs). However, the safety, efficacy, and tolerance of DAAs in the treatment of acute HCV infection in patients with end-stage renal disease who are on haemodialysis are unknown.

AIM

To evaluate the safety and efficacy of sofosbuvir plus daclatasvir in this specific, difficult-to-treat population.

METHODS

We conducted a prospective and observational study of end-stage renal disease patients who were undergoing haemodialysis and were acutely infected with HCV. Patients received a half dose of sofosbuvir (200 mg) and a full dose of daclatasvir (60 mg) daily. The primary endpoint was the proportion of patients with sustained virological responses (SVRs); the other primary outcomes were safety and tolerability.

RESULTS

Thirty-three patients were enrolled in the study. The median HCV RNA viral load at baseline was 6.8 log₁₀ IU/mL. Twenty-four patients were infected with HCV genotype 2a, seven patients with 1b, and two patients with 2a+1b. All patients achieved a SVR at 12 weeks after the end of treatment. The treatment was well tolerated, and there were no drug-related serious adverse events.

CONCLUSION

A half dose of sofosbuvir (200 mg once daily) plus a full dose of daclatasvir (60 mg once daily) were suitable for the treatment of acute HCV-infected patients who were undergoing end-stage renal disease and were on haemodialysis.

Kernohan-Woltman Notch Phenomenon Caused by Acute Traumatic Subdural Haematoma

A 27-year-old man suffered from right hemiparesis after a closed head injury. Computed tomography (CT) revealed a right hemisphere subdural haematoma with midline structure shifted to the left. The CT finding was believed to be mislabeled because the site of haematoma did not correlate with an ipsilateral hemiparesis. Magnetic resonance imaging revealed a right transtentorial uncal herniation and a small lesion within left cerebral peduncle, suggesting Kernohan-Woltman notch phenomenon (KWNP). KWNP has been rarely seen in patients with acute traumatic subdural haemorrhage. Anatomical small maximum tentorial notch width is the possible anatomical factor predisposing our patient to this phenomenon. (Hong Kong j.emerg.med. 2014;21:116-119)

[Prognostic study of visceral pleural invasion by pulmonary adenocarcinoma with tumor size ≤3 cm]

Objective: To evaluate the relationship between visceral pleural invasion (VPI) and other clinicopathological features in lung adenocarcinoma with tumor size ≤3 cm, and to investigate the impact of VPI on the patients' prognosis. Methods: The clinical and pathological features were retrospectively reviewed in 231 cases of lung adenocarcinoma with the largest diameter of tumor ≤3 cm, following complete resection and systemic lymphadenectomy. VPI was divided into three grades, PL0, PL1 and PL2 according to modified Hammar classification for lung cancer upon elastic fiber staining. Survival analysis was performed by Kaplan-Meier method, and the risk factors for prognosis were explored by Cox proportional hazards model. Patient prognosis was evaluated by progression-free survival (PFS) and overall survival (OS). Results: In all 231 cases, the number of patients with VPI was 70 (30.3%), of which 61 cases were PL1 and 9 cases were PL2. The remaining 161 cases (69.7%) had no VPI (PL0). The tumor size (P=0.003), histological grade (P<0.01), the presence of solid component (P=0.001) and micropapillary component (P=0.009), N stage (P<0.01) and TNM stage (P<0.01) were significantly correlated with VPI. Patients with VPI had significantly shorter PFS and OS than those without VPI (P<0.01). There were significant differences in PFS and OS between patients with different VPI levels (P<0.01). Cox multivariate regression analysis showed that VPI was not an independent prognostic factor, whereas PL2 was an independent prognostic factor for PFS (P=0.007), but not an independent prognostic factor for OS (P=0.052). Conclusions: For patients with lung adenocarcinoma of tumor size ≤3 cm, VPI is related to poor prognosis; However, only PL2 is an independent prognostic factor for PFS. It may be not necessary to separate PL0 and PL1 status in smaller lung adenocarcinomas. Therefore, the definition of VPI may need further modification through large cohort studies.

[Application of p16/Ki-67 immunocytochemistry in triage of patients with atypical squamous cells of undetermined significance]

Objective: To investigate the clinical value of p16/Ki-67 immunocytochemistry in patients with atypical squamous cells of undetermined significance(ASC-US). Methods: One hundred and seventy-one cases of thin-prep cytology test (TCT) diagnosed as ASC-US underwent p16/Ki-67 immunocytochemistry. All patients had colposcopy and biopsy from March 2015 to January 2016. Ninety of the 171 cases underwent high-risk HPV test at the same time. Results: p16/Ki-67 immunocytochemistry was positive in 43.9% (75/171) of the 171 cytology samples; the sensitivity and specificity of p16/Ki-67 immunocytochemistry were 77.6%(52/67) and 77.9%(81/104) in detecting CIN2+ , and the positive and negative predictive value were 69.3%(52/75) and 84.4%(81/96), respectively. The sensitivity and specificity in diagnosing CIN2+ were 100.0%(34/34) and 10.7%(6/56) for HPV test, and the positive and negative predictive value were 40.5%(34/84) and 6/6. p16/Ki-67 immunocytochemistry showed lower sensitivity but obviously higher specificity than high-risk HPV detection. Conclusion: p16/Ki-67 immunocytochemistry is a good triage test for identifying CIN2+ in ASC-US specimens.

Lactational oestrus and reproductive performance following a delayed limited nursing schedule in primiparous sows

With conventional lactation management, sows only conceive after weaning. However, intermittent suckling (IS) enables follicle growth and ovulation during lactation by reducing the suckling-induced inhibition of gonadotrophins. The current study evaluated IS regimes initiated at Day 21 or Day 28 post farrowing compared to conventional weaning on Day 28, in primiparous sows. Sows (Large White and Large White x Landrace) were randomly allocated to Control (C28; n = 44), IS21 (n = 29) and IS28 (n = 34) treatments at Day 20. Sows in IS21 and IS28 were subjected to intermittent suckling from Day 21 or Day 28 post farrowing. During IS, sows were separated from their piglets for 8 h daily, then weaned 7 d later at Day 28 and Day 35 respectively, whereas piglets in the C28 treatment had continuous access to sows until weaning at Day 28. Percentage of IS sows that showed oestrus during lactation was 59% (16/27) in IS21 and 72% (21/29) in IS28 (P > 0.05). Cumulatively over the lactation and 7 d post-weaning period, 93% of IS21, 85% of IS28 and 93% (31/33) of C28 sows showed oestrus (P > 0.05). Pregnancy rate at Day 30 post mating, for sows that were mated during lactation was 93% (15/16) in IS21 and 95% (20/21) in IS28, whereas C28 sows had a 96% (30/31) pregnancy rate (P > 0.05). No difference was found in the time of oestrus relative to weaning (C28) or onset of IS (IS21 and IS28) (P > 0.05). The IS sows that did not ovulate before weaning all showed oestrus within 7 days from weaning, and the weaning to oestrus interval was similar to control sows (P > 0.05). However, for all IS sows (across IS treatments) that showed lactational ovulation, LH secretion pattern at onset of IS was different (P < 0.05) from the sows that did not ovulate in lactation. Plasma progesterone concentration tended to be lower in the IS21 treatment (P < 0.10) compared to the C28 sows at 4 d after ovulation. The subsequent litter size was not affected by treatments although numerically lower for IS21 (P > 0.05). The present study showed that in modern primiparous sows, lactational oestrus can be induced and pregnancy can be maintained at a similar rate and producing comparable subsequent litter sizes to conventionally weaned sows when IS commenced at four weeks post farrowing. However, when IS commences at three weeks post farrowing, this may affect the percentage of sows showing oestrus in lactation and may potentially influence subsequent litter size.

[Characteristics of HBV transmission in families with HBsAg-positive fathers and familial clustering of HBV infection]

OBJECTIVE

To investigate the characteristics of hepatitis B virus (HBV) transmission among family members in families with familial clustering of HBV infection and poor outcomes, as well as the prevalence and distribution characteristics of HBsAg in offspring with different parental HBsAg status.

METHODS

The general information of each member in families with poor outcomes were collected from 2007 to 2010, and serological test was performed to analyze the prevalence and distribution of HBsAg in family members. The chi-square test or Fisher's exact test was used to analyze and compare the sex of offspring and the prevalence of HBsAg in them in 266 nuclear families with different paternal and maternal HBsAg status.

RESULTS

The positive rates of HBsAg in parents, siblings, children, and spouses of the probands were 20%, 88.2%, 76.8%, and 9.5%, respectively. The nuclear families with HBsAg-positive fathers and HBsAg-negative mothers had a significantly increased proportion of male offspring (male/female ratio = 2.02) compared with those with HBsAg-positive mothers and HBsAg-negative fathers (1.22) or those with HBsAg-negative fathers and mothers (0.96). In addition, in the nuclear families with HBsAg-positive fathers and HBsAg-negative mothers, the male offspring had a significantly higher HBsAg positive rate than female offspring (37.4% vs 13.8%), while in those with HBsAg-positive mothers and HBsAg-negative fathers or those with HBsAg-negative fathers and mothers, HBsAg positive rate showed no significant difference between male and female offspring.

CONCLUSION

In families with familial clustering of HBV infection and poor outcomes, mother-to-child transmission is still the major route of HBV transmission, but father-to-child transmission also plays a role in HBV transmission in this special population. Positive HBsAg in fathers is associated with the increased proportion of male offspring, and father-to-son transmission of HBV is higher than father-to-daughter transmission.

Single-molecule dynamics of the molecular chaperone trigger factor in living cells

In bacteria, trigger factor (TF) is the molecular chaperone that interacts with the ribosome to assist the folding of nascent polypeptides. Studies in vitro have provided insights into the function and mechanism of TF. Much is to be elucidated, however, about how TF functions in vivo. Here, we use single-molecule tracking, in combination with genetic manipulations, to study the dynamics and function of TF in living E. coli cells. We find that TF, besides interacting with the 70S ribosome, may also bind to ribosomal subunits and form TF-polypeptide complexes that may include DnaK/DnaJ proteins. The TF-70S ribosome interactions are highly dynamic inside cells, with an average residence time of ∼0.2 s. Our results confirm that the signal recognition particle weakens TF's interaction with the 70S ribosome, and further identify that this weakening mainly results from a change in TF's binding to the 70S ribosome, rather than its unbinding. Moreover, using photoconvertible bimolecular fluorescence complementation, we selectively probe TF₂ dimers in the cell and show that TF₂ does not bind to the 70S ribosome but is involved in the post-translational interactions with polypeptides. These findings contribute to the fundamental understanding of molecular chaperones in assisting protein folding in living cells.

Elevating glucose and insulin secretion by carbohydrate formulation diets in late lactation to improve post-weaning fertility in primiparous sows

Primiparous (P1) sows commonly lose excessive body reserves to meet energy requirements for maintenance and milk production during lactation, and consequently, post-weaning reproductive performance may be compromised. The present studies determined whether ad libitum feeding a glucogenic carbohydrate diet (CHO) during late lactation could stimulate insulin and glucose secretion (experiment 1) and improve subsequent litter size (experiment 2). For experiment 1, 15 P1 sows, and for experiment 2, 99 P1 sows (198.5 ± 2.7 kg) were allocated randomly according to suckled litter size (≥10 piglets), either to a CHO diet (14.3 MJ DE/kg, 19.8% crude protein) or a standard lactation diet (control; 14.2 DE MJ/kg, 19.5% crude protein) at 8 days before weaning. The CHO diet aimed to provide glucogenic content (extruded wheat, dextrose and sugar) as energy sources instead of fat sources without changing total dietary energy. Pre-prandial plasma glucose and insulin concentrations were not influenced by treatments. However, post-prandial plasma glucose and insulin concentrations and their peaks were both higher (p < .05) compared to the control treatment. Body weight loss during lactation was relatively low at 3%-4% for both treatments and did not differ between control and CHO treatments (-7.6 ± 1.6 vs -5.4 ± 1.2 kg; p > .05). Second litter size was not influenced by diet (p > .05), but the weaning-to-mating interval was shorter in CHO sows (p < .05). This study demonstrates that providing an enriched CHO diet in late lactation did influence post-weaning follicle growth but did not improve subsequent litter size. This may be due to the primiparous sows in this study not experiencing severe negative energy balance and there was no second litter syndrome in this farm which limited the ability of diet to improve sow fertility.

Human chorionic gonadotrophin in early gestation induces growth of estrogenic ovarian follicles and improves primiparous sow fertility during summer

Reduced summer farrowing rates may be due to inadequate corpora luteal (CL) support. Porcine CL become dependent on LH from 12 d of pregnancy and the embryonic estrogen signal for maternal recognition of pregnancy (MRP) is initiated at about 11-12 d after insemination. We hypothesised that injection of the LH analogue human chorionic gonadotropin (hCG) would induce growth of estrogenic follicles and, by mimicking the signal for MRP and stimulating progesterone secretion, increase primiparous sow fertility. In Experiment 1, during a 28 d lactation 53 mixed parity sows were full-fed either throughout lactation (n=16) or until 18 d and then feed restricted during the last 10 d of lactation (n=36). At 12 d after mating restrict-fed sows were injected with 1000IU hCG (n=17) or were not injected (n=19); the full-fed sows acted as non-treated positive controls. Transrectal ovarian ultrasound exams were performed on days 12, 16, 20, 24, and 28; blood samples were obtained on days 12, 14, and 15 for estradiol and progesterone assay. For Experiment 2, during the summer months primiparous sows received 1000IU hCG 12 d after mating (n=28) or were non-injected controls (n=27). Pregnancy status was determined at 28 d and sows allowed to go to term to determine farrowing rates and litter sizes. In Experiment 1, injection of hCG increased (P<0.001) follicle diameter and serum concentrations of estradiol (P<0.01) and progesterone (P<0.05). There were no effects of lactation feeding level on wean-estrus interval, farrowing rate or subsequent litter size. In Experiment 2, hCG injection was associated with a higher pregnancy rate (P<0.05) and farrowing rate (P<0.08). There was no effect on litter size. These data confirm that hCG stimulates growth of estrogenic follicles and CL function, and improves primiparous sow fertility during the summer months.

Quantifying Multistate Cytoplasmic Molecular Diffusion in Bacterial Cells via Inverse Transform of Confined Displacement Distribution

Single-molecule tracking (SMT) of fluorescently tagged cytoplasmic proteins can provide valuable information on the underlying biological processes in living cells via subsequent analysis of the displacement distributions; however, the confinement effect originated from the small size of a bacterial cell skews the protein’s displacement distribution and complicates the quantification of the intrinsic diffusive behaviors. Using the inverse transformation method, we convert the skewed displacement distribution (for both 2D and 3D imaging conditions) back to that in free space for systems containing one or multiple (non)interconverting Brownian diffusion states, from which we can reliably extract the number of diffusion states as well as their intrinsic diffusion coefficients and respective fractional populations. We further demonstrate a successful application to experimental SMT data of a transcription factor in living E. coli cells. This work allows a direct quantitative connection between cytoplasmic SMT data with diffusion theory for analyzing molecular diffusive behavior in live bacteria.

Difference between patients' and clinicians' perception of pouch dysfunction and its impact on quality of life following restorative proctocolectomy

AIM

The Pouch Dysfunction Score (PDS) is a five-item instrument that evaluates bowel function and quality of life following restorative proctocolectomy for ulcerative colitis. The PDS includes items that have a significantly negative impact on quality of life from the patient's point of view. The study aimed to establish how pouch dysfunction is perceived by clinicians in relation to patients experience.

METHOD

Fifty-eight leading clinicians in the field of inflammatory bowel disease were invited to complete two PDS-based exercises. In part 1, they received a list of the 12 bowel symptoms from which the PDS had been developed and were asked to identify and rank (in order of severity) the five they thought had the most significantly negative impact on quality of life. In part 2, they were given the list of symptoms perceived by patients to be most troublesome and were then required to enter a score that they thought was appropriate for each item according to the impact on quality of life.

RESULTS

Forty-three clinicians responded, and each correctly identified one to three items selected by patients and included in the PDS. Severity of urgency was selected by 29 (67%) clinicians, and four (9%) rated it to be the most important. Incomplete emptying after defaecation was selected by 10 (23%). Frequency of defaecation and the use of anti-diarrhoeal medication were selected by 14 (33%) and three (7%) clinicians, respectively. Twenty-six (60%) did not include incomplete emptying and 25 (58%) did not include uncontrolled loss of stool in their selection.

CONCLUSION

This study demonstrates that clinicians do not have a great understanding of the symptoms of pouch dysfunction that really matter to the patient.

The acoustic radiation force impulse elastography evaluation of liver fibrosis in posttransplantation dysfunction of living donor liver transplantation

BACKGROUND

The acoustic radiation force impulse elastography (ARFI) is a new technology of elastography integrated into B-mode ultrasonography. It has been a reliable method to evaluate liver fibrosis of chronic liver disease in recent years, but less applied in the posttransplantation liver. The aim of the study was to evaluate liver fibrosis by the ARFI with correlation of pathological stages in living donor liver transplantation (LDLT).

MATERIALS AND METHODS

From August 2010 to August 2012, there were 57 LDLT patients with liver biopsy (LB) due to posttransplantation dysfunction; all patients also received posttransplantation ARFI liver stiffness measurement (LSM) after transplantation for liver fibrosis staging. The ARFI elastography was performed using a Siemens Acuson S2000 ultrasound system with 4V1 transducers (Acusion, Siemens Medical Systems Co. Ltd. Erlangen, Germany). The ARFI LSM value was presented by shear wave velocity (SWV, m/s). The fibrosis staging as F0 to F4 was in accordance with the Metavir scoring system.

RESULTS

A total of 57 patients had both posttransplantation LB and effective ARFI fibrosis staging for correlation. The ARFI LSM value increased with severity of liver fibrosis and had significant linear correlation with the results of histological fibrosis staging. The ARFI LSM sensitivities (Se), specificities (Sp), and cutoff values based on receiver-operator characteristic curve were F0: 0.75 m/s (Se: 93.8%, Sp: 4%), F1: 1.06 m/s (Se: 95.5%, Sp: 25.7%), F2: 1.81 m/s (Se: 50%, Sp: 83.6%) and F3: 2.33 m/s (Se: 100%, Sp: 92.9%). Predictive value of ARFI LSM reported a significant difference between early fibrosis stage (F0-F1) and advanced fibrosis stage (F ≧ 2) (P < .05).

CONCLUSION

In this study, ARFI demonstrated a strong linear correlation and severity of liver fibrosis with LB pathologic staging. ARFI can be an alternative and compensatory method for frequent LB in the posttransplantation liver.

Synergistic effects of arsenic trioxide combined with ascorbic acid in human osteosarcoma MG-63 cells: a systems biology analysis

OBJECTIVE

To further understand the synergistic mechanism of As2O3 and asscorbic acid (AA) in human osteosarcoma MG-63 cells by systems biology analysis.

MATERIALS AND METHODS

Human osteosarcoma MG-63 cells were treated by As2O3 (1 µmol/L), AA (62.5 µmol/L) and combined drugs (1 µmol/L As2O3 plus 62.5 µmol/L AA). Dynamic morphological characteristics were recorded by Cell-IQ system, and growth rate was calculated. Illumina beadchip assay was used to analyze the differential expression genes in different groups. Synergic effects on differential expression genes (DEGs) were analyzed by mixture linear model and singular value decomposition model. KEGG pathway annotations and GO enrichment analysis were performed to figure out the pathways involved in the synergic effects.

RESULTS

We captured 1987 differential expression genes in combined therapy MG-63 cells. FAT1 gene was significantly upregulated in all three groups, which is a promising drug target as an important tumor suppressor analogue; meanwhile, HIST1H2BD gene was markedly downregulated in the As2O3 monotherapy group and the combined therapy group, which was found to be upregulated in prostatic cancer. These two genes might play critical roles in synergetic effects of AA and As2O3, although the exact mechanism needs further investigation. KEGG pathway analysis showed many DEGs were related with tight junction, and GO analysis also indicated that DEGs in the combined therapy cells gathered in occluding junction, apical junction complex, cell junction, and tight junction.

CONCLUSIONS

AA potentiates the efficacy of As2O3 in MG-63 cells. Systems biology analysis showed the synergic effect on the DEGs.

Single-molecule dynamics and mechanisms of metalloregulators and metallochaperones

Understanding how cells regulate and transport metal ions is an important goal in the field of bioinorganic chemistry, a frontier research area that resides at the interface of chemistry and biology. This Current Topic reviews recent advances from the authors' group in using single-molecule fluorescence imaging techniques to identify the mechanisms of metal homeostatic proteins, including metalloregulators and metallochaperones. It emphasizes the novel mechanistic insights into how dynamic protein-DNA and protein-protein interactions offer efficient pathways via which MerR-family metalloregulators and copper chaperones can fulfill their functions. This work also summarizes other related single-molecule studies of bioinorganic systems and provides an outlook toward single-molecule imaging of metalloprotein functions in living cells.

Effect of surfactant and solvent on spin-lattice relaxation dynamics of magnetic nanocrystals

The effect of varying the surfactant and solvent medium on the dynamics of spin-lattice relaxation in photoexcited Fe3O4 nanocrystals has been investigated by measuring the time-dependent magnetization employing pump-probe transient Faraday rotation technique. The variation of the surfactants having surface-binding functional groups modified not only the static magnetization but also the dynamics of the recovery of the magnetization occurring via spin-lattice relaxation in the photoexcited Fe3O4 nanocrystals. The variation of the polarity and size of the solvent molecules can also influence the spin-lattice relaxation dynamics. However, the effect is limited to the nanocrystals having sufficiently permeable surfactant layer, where the small solvent molecules (e.g., water) can access the surface and dynamically modify the ligand field on the surface.

Undernutrition during early follicle development has irreversible effects on ovulation rate and embryos

This study assessed carry-over effects of energy level during the early antral phase and subsequent follicular phase on follicle recruitment and ovulation rate. Gilts (n=45) were fed a standard diet to a low (L, ~1.2kg day(-1)) or high (H, ~2.7kg day(-1)) level during the early antral (luteal) phase, and subsequently fed a H or L feed level during the follicular phase, resulting in four treatment groups (HH, HL, LH and LL). Follicle size at the end of the luteal phase was greater for gilts fed a high feed level previously (3.3vs3.0mm; P<0.05). During the follicular phase, high feeding increased follicle size at Day 5 (6.9vs6.2mm; P<0.005) and plasma oestradiol concentration (P<0.05). Nevertheless, a low feed level during the luteal phase reduced ovulation rate (14.4vs13.2; P<0.05) and embryo number (12.6vs10.5; P<0.05), and this was not counteracted by feed level during the follicular phase. Plasma progesterone concentration after ovulation was lower for LL gilts than for other treatments (P<0.05). These results indicate that undernutrition during early antral follicle development may have a residual effect on follicle recruitment and quality.

Unified formalism of Andreev reflection at a ferromagnet/superconductor interface

We present a unified formalism of Andreev reflection of a partial polarized current at a ferromagnet/superconductor interface instead of assuming a linear combination of unpolarized and polarized currents. The Andreev reflection is limited by the states of minority spins and the extra majority spins become evanescent wave. We further study the effects of spin polarization, inelastic scattering, and interfacial scattering on the Andreev reflection, normal reflection, and transmitted probabilities in equilibrium as well as under a bias. Our model, which reduces to those of Blonder, Tinkham, and Klapwijk, Mazin, and Dynes in three limiting cases, provides a significantly better description of the experimental results.

Transport magnetic proximity effects in platinum

Platinum (Pt) metal, being nonmagnetic and with a strong spin-orbit coupling interaction, has been central in detecting the pure spin current and establishing most of the recent spin-based phenomena. Magnetotransport measurements, both electrical and thermal, conclusively show strong ferromagnetic characteristics in thin Pt films on the ferromagnetic insulator due to the magnetic proximity effects. The pure spin current phenomena measured by Pt, including the inverse spin Hall and the spin Seebeck effects, are thus contaminated and not exclusively established.

Surface roughness dominated pinning mechanism of magnetic vortices in soft ferromagnetic films

Although pinning of domain walls in ferromagnets is ubiquitous, the absence of an appropriate characterization tool has limited the ability to correlate the physical and magnetic microstructures of ferromagnetic films with specific pinning mechanisms. Here, we show that the pinning of a magnetic vortex, the simplest possible domain structure in soft ferromagnets, is strongly correlated with surface roughness, and we make a quantitative comparison of the pinning energy and spatial range in films of various thickness. The results demonstrate that thickness fluctuations on the lateral length scale of the vortex core diameter, i.e., an effective roughness at a specific length scale, provides the dominant pinning mechanism. We argue that this mechanism will be important in virtually any soft ferromagnetic film.