DEAD-box helicase 1 inhibited CD8+ T cell antitumor activity by inducing PD-L1 expression in hepatocellular carcinoma.

Hepatocellular carcinoma (HCC) does not respond well to current treatments, even immune checkpoint inhibitors. PD-L1 (programmed cell death ligand 1 or CD274 molecule)-mediated immune escape of tumor cells may be a key factor affecting the efficacy of immune checkpoint inhibitor (ICI) therapy. However, the regulatory mechanisms of PD-L1 expression and immune escape require further exploration. Here, we observed that DDX1 (DEAD-box helicase 1) was overexpressed in HCC tissues and associated with poor prognosis in patients with HCC. Additionally, DDX1 expression correlated negatively with CD8+ T cell frequency. DDX1 overexpression significantly increased interferon gamma (IFN-γ)-mediated PD-L1 expression in HCC cell lines. DDX1 overexpression decreased IFN-γ and granzyme B production in CD8+ T cells and inhibited CD8+ T cell cytotoxic function in vitro and in vivo. In conclusion, DDX1 plays an essential role in developing the immune escape microenvironment, rendering it a potential predictor of ICI therapy efficacy in HCC.

Ab initio studies of counterion effects in molecular quantum-dot cellular automata.

Molecular quantum-dot cellular automata (QCA) is a low-power computing paradigm that may offer ultra-high device densities and THz-speed switching at room temperature. A single mixed-valence (MV) molecule acts as an elementary QCA device known as a cell. Cells coupled locally via the electrostatic field form logic circuits. However, previously-synthesized ionic MV molecular cells are affected by randomly-located, nearby neutralizing counterions that can bias device states or change device characteristics, causing incorrect computational results. This ab initio study explores how non-biasing counterions affect individual molecular cells. Additionally, we model two novel neutral, zwitterionic MV QCA molecules designed to avoid biasing and other undesirable counterionic effects. The location of the neutralizing counterion is controlled by integrating one counterion into each cell at a well-defined, non-biasing location. Each zwitterionic QCA candidate molecule presented here has a fixed, integrated counterion, which neutralizes the mobile charges used to encode the device state.

Designing boron-cluster-centered zwitterionic Y-shaped clocked QCA molecules.

Quantum-dot cellular automata (QCA) is a nanoscale, transistor-less device technology. A single molecule may provide an elementary QCA device known as a cell. Molecular redox centers function as quantum dots, and the configuration of mobile charge on the dots encodes device states useful for classical computing. Molecular QCA may support ultra-high device densities and THz-scale switching speeds at room temperature. An applied electric field may be used to clock molecular QCA, providing power gain to boost weakened signals, as well as quasi-adiabatic device operation for minimal power dissipation in QCA devices and circuits. A zwitterionic, Y-shaped, three-dot molecule may function as a field-clocked QCA cell. We focus on the design of a counterion built into the center of the cell.Ab initiocomputations demonstrate that choice of counterion determines the number of mobile charges for encoding the device state on the three quantum dots. We useB5H52-orB4CH5-as the central counterionic linker for two different Y-shaped, three-dot QCA molecules. While both molecules support the desired device states, the number of trapped charges in the counterion determines the number of mobile holes on the molecular quantum dots. This, in turn, determines whether the device state is encoded by a hole or an electron. This choice of encoding determines how the molecular QCA cell responds to a clocking field. The two counterions studied here lead to two QCA molecules with opposite responses to the clock, similar to the complementary responses of PMOS and NMOS transistors to gated voltage control.

Synergistic Chemical and Photodynamic Antimicrobial Therapy for Enhanced Wound Healing Mediated by Multifunctional Light-Responsive Nanoparticles.

Recently, rapid acquisition of antibiotic resistance, increased prevalence of antibiotic-resistant bacterial infections, and slow healing of infected wound have led to vast difficulties in developing innovative antimicrobial agents to obliterate pathogenic bacteria and simultaneously accelerate wound healing. To effectively solve this problem, we designed light-responsive multifunctional nanoparticles with conjugation of quaternary ammonium chitosan and photosensitizer chlorin e6 (Ce6) to merge chemical and photodynamic therapy to efficient antibacteria. The Mg/(-)-epigallocatechin-3-gallate (EGCG) complex rapidly responded to light irradiation under 660 nm with release of magnesium ions, which effectively accelerated wound healing without toxicity to mammalian cells. Notably, positively charged nanoparticles could efficiently adhere to the bacterial surface, and reactive oxygen species (ROS) produced under laser irradiation destroyed the membrane structure of the bacteria, which is irreversible, ultimately leading to bacteria death. Thus, multifunctional nanoparticles with a combination of chemical and photodynamic antimicrobial therapy would offer guidance to rational predicted and designed new effective antimicrobial nanomaterials. Most importantly, it may represent a promising class of antimicrobial strategy for potential clinical translation.

Synthesis of a Neutral Mixed-Valence Diferrocenyl Carborane for Molecular Quantum-Dot Cellular Automata Applications.

The preparation of 7-Fc(+) -8-Fc-7,8-nido-[C2 B9 H10 ](-) (Fc(+) FcC2 B9 (-) ) demonstrates the successful incorporation of a carborane cage as an internal counteranion bridging between ferrocene and ferrocenium units. This neutral mixed-valence Fe(II) /Fe(III) complex overcomes the proximal electronic bias imposed by external counterions, a practical limitation in the use of molecular switches. A combination of UV/Vis-NIR spectroscopic and TD-DFT computational studies indicate that electron transfer within Fc(+) FcC2 B9 (-) is achieved through a bridge-mediated mechanism. This electronic framework therefore provides the possibility of an all-neutral null state, a key requirement for the implementation of quantum-dot cellular automata (QCA) molecular computing. The adhesion, ordering, and characterization of Fc(+) FcC2 B9 (-) on Au(111) has been observed by scanning tunneling microscopy.

Effects of reduced graphene oxide nanomaterials on transformation of 14C-triclosan in soils.

Increasing use and release of graphene nanomaterials and pharmaceutical and personal care products (PPCPs) in soil environment have polluted the environment and posed high ecological risks. However, little is understood about the interactive effects and mechanism of graphene on the behaviors of PPCPs in soil. In the present study, the effects of reduced graphene oxide nanomaterials (RGO) on the fate of triclosan in two typical soils (S1: silty loam; S2: silty clay loam) were investigated with 14C-triclosan, high-resolution mass spectrometry, scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), density functional theory (DFT) calculations, and microbial community structure analysis. The results showed that RGO prolonged the half-life of triclosan by 23.6-51.3 %, but delayed the formation of transformed products such as methyl triclosan and dechlorinated dimer of triclosan in the two typical soils. Mineralization of triclosan to 14CO2 was inhibited by 48.2-79.3 % in 500 mg kg-1 RGO in comparison with that in the control, whereas the bound residue was 54.2-56.4 % greater than the control. RGO also reduced the relative abundances of triclosan-degrading bacteria (Pseudomonas and Sphingomonas) in soils. Compared to silty loam, RGO more effectively inhibited triclosan degradation in silty clay loam. Furthermore, the DFT calculations suggested a strong association of the adsorption of triclosan on RGO with the van der Waals forces and π-π interactions. These results revealed that RGO inhibited the transformation of 14C-triclosan in soil through strong adsorption and triclosan-degrading bacteria inhibition in soils. Therefore, the presence of RGO may potentially enhance persistence of triclosan in soil. Overall, our study provides valuable insights into the risk assessment of triclosan in the presence of GNs in soil environment.

Fufang Luohanguo Qingfei granules reduces influenza virus susceptibility via MAVS-dependent type I interferon antiviral signaling.

ETHNOPHARMACOLOGICAL RELEVANCE: Fufang Luohanguo Qingfei granules (LQG) is a Chinese patent medicine, clinically used to treat flu-like symptoms including cough with yellow phlegm, impeded phlegm, dry throat and tongue. However, the protective activity of LQG against influenza infection is indeterminate. AIM OF THE STUDY: This study is to investigate the therapeutic effect of LQG on influenza infection and elucidate its underlying mechanism. MATERIALS AND METHODS: In vivo: A viral susceptible mouse model induced by restraint stress was established to investigate LQG's beneficial effects on influenza susceptibility. MAVS knockout (Mavs-/-) mice were used to verify the potential mechanism of LQG. In vitro: Corticosteroid (CORT)-treated A549 cells were employed to identify the active ingredients in LQG. Mice morbidity and mortality were monitored daily for 21 days. Histopathologic changes and inflammatory cytokines in lung tissues were examined by H&E staining and ELISA. RNA-seq was used to explore the signaling pathway influenced by LQG and further confirmed by qPCR. Immunoblotting and immunohistochemistry (IHC) were used to determine the protein levels. CO-IP and DARTS were applied to detect protein-protein interaction and compound-protein interaction, respectively. RESULTS: LQG effectively attenuated the susceptibility of restrained mice to H1N1 infection. LQG significantly boosted the production of IFN-ß transduced by mitochondrial antiviral-signaling protein (MAVS), while MAVS deficiency abrogated its protective effects on restrained mice infected with H1N1. Moreover, in vitro studies further revealed that mogroside Ⅱ B, amygdalin, and luteolin are potentially active components of LQG. CONCLUSION: These results suggested that LQG inhibited the mitofusin 2 (Mfn2)-mediated ubiquitination of MAVS by impeding the E3 ligase synoviolin 1 (SYVN1) recruitment, thereby enhancing IFN-ß antiviral response. Overall, our work elaborates a potential regimen for influenza treatment through reduction of stress-induced susceptibility.

Regulation of hepatocyte phospholipid peroxidation signaling by a Chinese patent medicine against psychological stress-induced liver injury.

BACKGROUND: Psychological stress is associated with various diseases including liver dysfunction, yet effective intervention strategies remain lacking due to the unrevealed pathogenesis mechanism. PURPOSE: This study aims to explore the relevance between BMAL1-controlled circadian rhythms and lipoxygenase 15 (ALOX15)-mediated phospholipids peroxidation in psychological stress-induced liver injury, and to investigate whether hepatocyte phospholipid peroxidation signaling is involved in the hepatoprotective effects of a Chinese patent medicine, Pien Tze Huang (PZH). METHODS: Restraint stress models were established to investigate the underlying molecular mechanisms of psychological stress-induced liver injury and the hepatoprotective effects of PZH. Redox lipidomics based on liquid chromatography-tandem mass spectrometry was applied for lipid profiling. RESULTS: The present study discovered that acute restraint stress could induce liver injury. Notably, lipidomic analysis confirmed that phospholipid peroxidation was accumulated in the livers of stressed mice. Additionally, the essential core circadian clock gene Brain and Muscle Arnt-like Protein-1 (Bmal1) was altered in stressed mice. Circadian disruption in mice, as well as BMAL1-overexpression in human HepaRG cells, also appeared to have a significant increase in phospholipid peroxidation, suggesting that stress-induced liver injury is closely related to circadian rhythm and phospholipid peroxidation. Subsequently, arachidonate 15-lipoxygenase (ALOX15), a critical enzyme that contributed to phospholipid peroxidation, was screened as a potential regulatory target of BMAL1. Mechanistically, BMAL1 promoted ALOX15 expression via direct binding to an E-box-like motif in the promoter. Finally, this study revealed that PZH treatment significantly relieved pathological symptoms of psychological stress-induced liver injury with a potential mechanism of alleviating ALOX15-mediated phospholipid peroxidation. CONCLUSION: Our findings illustrate the critical role of BMAL1-triggered phospholipid peroxidation in psychological stress-induced liver injury and provide new insight into treating psychological stress-associated liver diseases by TCM intervention.

Mechanism of Xiezhuo Huayu Yiqi Tongluo Formula in the Treatment of Uric Acid Nephropathy Based on Network Pharmacology, Molecular Docking, and In Vivo Experiments.

Background: Xiezhuo Huayu Yiqi Tongluo Formula (XHYTF) consists of 14 Chinese herbal medicines. In this study, we investigated the potential mechanism of XHYTF in the treatment of uric acid nephropathy (UAN) through network pharmacology, molecular docking, and in vivo methods. Methods: Using various pharmacological databases and analysis platforms, information on the active ingredients and targets of Chinese herbal medicine was collected, and UAN disease targets were retrieved using OMIM, Gene Cards, and NCBI. Then common target proteins were integrated. A Drug-Component-Target (D-C-T) map was constructed to screen core compounds and build a protein-protein interaction (PPI) network. Further, Gene Ontology (GO) enrichment analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis were performed for common targets, and a Drug-Component-Target-Pathway (D-C-T-P) network diagram was constructed. The molecular docking simulation was performed to verify the binding affinity between core components and hub targets. Subsequently, the UAN rat model was established, followed by the collection of serum and renal tissues. The expression levels of indicators in the serum were determined using an enzyme-linked immunosorbent assay. The pathological changes of renal tissues were detected using H & E staining and Masson staining. The expression of related proteins in renal tissue was detected by western blot. Results: In the study, 216 active ingredients and 439 targets in XHYTF were screened, and 868 targets were identified as being related to UAN. Among them, 115 were common targets. Based on the D-C-T network, quercetin, luteolin, ß-sitosterol, and stigmasterol were observed to be the key active ingredients of XHYTF that were effective against UAN. The analysis of the PPI network revealed TNF, IL6, AKT1, PPARG, and IL1ß as the 5 key targets. GO enrichment analysis revealed that the pathways were mainly concentrated in cell killing, regulation of signaling receptor activity, and other activities. Subsequently, KEGG pathway analysis revealed that multiple signaling pathways, including the HIF-1, PI3K-Akt, IL-17, and other signaling pathways, were closely related to the action of XHYTF. All 5 key targets were confirmed to interact with all core active ingredients. In vivo experiments indicated that XHYTF significantly reduced blood uric acid and creatinine levels, alleviated inflammatory cell infiltration in kidney tissues, reduced the levels of serum inflammatory factors such as TNF-α and IL1ß, and ameliorated renal fibrosis in rats with UAN. Finally, western blot revealed decreased levels of PI3K and AKT1 proteins in the kidney, which confirmed the hypothesis. Conclusion: Collectively, our observations demonstrated that XHYTF significantly protects kidney function, including alleviation of inflammation and renal fibrosis via multiple pathways. This study provided novel insights into the treatment of UAN using traditional Chinese medicines.

Scutellaria baicalensis: a promising natural source of antiviral compounds for the treatment of viral diseases.

Viruses, the smallest microorganisms, continue to present an escalating threat to human health, being the leading cause of mortality worldwide. Over the decades, although significant progress has been made in the development of therapies and vaccines against viral diseases, the need for effective antiviral interventions remains urgent. This urgency stems from the lack of effective vaccines, the severe side effects associated with current drugs, and the emergence of drug-resistant viral strains. Natural plants, particularly traditionally-used herbs, are often considered an excellent source of medicinal drugs with potent antiviral efficacy, as well as a substantial safety profile. Scutellaria baicalensis, a traditional Chinese medicine, has garnered considerable attention due to its extensive investigation across diverse therapeutic areas and its demonstrated efficacy in both preclinical and clinical trials. In this review, we mainly focused on the potential antiviral activities of ingredients in Scutellaria baicalensis, shedding light on their underlying mechanisms of action and therapeutic applications in the treatment of viral infections.

Through-bond versus through-space coupling in mixed-valence molecules: observation of electron localization at the single-molecule scale.

Scanning tunneling microscopy (STM) is used to study two dinuclear organometallic molecules, meta-Fe2 and para-Fe2, which have identical molecular formulas but differ in the geometry in which the metal centers are linked through a central phenyl ring. Both molecules show symmetric electron density when imaged with STM under ultrahigh-vacuum conditions at 77 K. Chemical oxidation of these molecules results in mixed-valence species, and STM images of mixed-valence meta-Fe2 show pronounced asymmetry in electronic state density, despite the structural symmetry of the molecule. In contrast, images of mixed-valence para-Fe2 show that the electronic state density remains symmetric. Images are compared to constrained density functional (CDFT) calculations and are consistent with full localization of charge for meta-Fe2 on to a single metal center, as compared with charge delocalization over both metal centers for para-Fe2. The conclusion is that electronic coupling between the two metal centers occurs through the bonds of the organic linker, and through-space coupling is less important. In addition, the observation that mixed-valence para-Fe2 is delocalized shows that electron localization in meta-Fe2 is not determined by interactions with the Au(111) substrate or the position of neighboring solvent molecules or counterion species.

Unscheduled return visits with and without admission post emergency department discharge.

BACKGROUND: Monitoring unscheduled return visits to the Emergency Department (ED) is useful to identify medical errors. OBJECTIVE: To investigate the differences between unscheduled return visit admissions (URVA) and unscheduled return visit no admissions (URVNA) after ED discharge. METHODS: From January 1, 2008 to March 31, 2008, URVA and URVNA patients who returned within 3 days after ED discharge were enrolled in the study. We compared the clinical characteristics, underlying diseases, ED crowding indicators, staff experience at the patient's first visit, and several other risk factors. We used multivariate logistic regression to evaluate differences between the two groups and to identify predictors of admission from unscheduled return visits. RESULTS: The unscheduled return visit rate was 3.1%. Of the 413 patients included, 147 patients (36%) were admitted, and had a mortality rate of 4.1%. The most common reason for the return visit was an illness-based factor (47.9%). Compared to URVNA patients, unscheduled return visit admissions had higher prevalence rates for old age, non-ambulatory status, high-grade triage, and underlying diseases (e.g., malignancy, diabetes mellitus, hypertension, coronary artery disease, heart failure, and chronic obstructive pulmonary disease). The independent predictors for URVA were: age≥65 years (adjusted odds ratio [OR] 2.2, 95% confidence interval [CI] 1.4-3.5); high-grade triage (adjusted OR 2.1, 95% CI 1.3-3.2); and doctor-based factors (adjusted OR 3.5, 95% CI 2.0-6.1). More advanced staff experience (p=0.490) and ED crowding were not significant predictors (p=0.498 for whole-day number of patients, p=0.095 for whole-shift number of patients). CONCLUSION: Old age, high-grade triage, and doctor-based factors were found to be significant predictors for URVA, whereas advanced staff experience and ED crowding were not.

Nucleosome-Omics: A Perspective on the Epigenetic Code and 3D Genome Landscape.

Genetic information is loaded on chromatin, which involves DNA sequence arrangement and the epigenetic landscape. The epigenetic information including DNA methylation, nucleosome positioning, histone modification, 3D chromatin conformation, and so on, has a crucial impact on gene transcriptional regulation. Out of them, nucleosomes, as basal chromatin structural units, play an important central role in epigenetic code. With the discovery of nucleosomes, various nucleosome-level technologies have been developed and applied, pushing epigenetics to a new climax. As the underlying methodology, next-generation sequencing technology has emerged and allowed scientists to understand the epigenetic landscape at a genome-wide level. Combining with NGS, nucleosome-omics (or nucleosomics) provides a fresh perspective on the epigenetic code and 3D genome landscape. Here, we summarized and discussed research progress in technology development and application of nucleosome-omics. We foresee the future directions of epigenetic development at the nucleosome level.

Reduced graphene oxide accelerates the dissipation of 14C-Triclosan in paddy soil via adsorption interactions.

Reduced graphene oxide (RGO) is one of common carbon nanomaterials, which is widely used in various fields. Triclosan is an antimicrobial agent added in pharmaceuticals and personal care products. Extensive release of RGO and triclosan has posed potential risks to humans and the environment. The impact of RGO on the fate of triclosan in paddy soil is poorly known. 14C-Triclosan was employed in the present study to determine its distribution, degradation and mineralization in paddy soil mixed with RGO. Compared with the control, RGO (500 mg kg-1) significantly inhibited the mineralization of 14C-triclosan, and reduced its extractability by 6.5%. The bound residues of triclosan in RGO-contaminated soil (100 and 500 mg kg-1) were 2.9-13.3% greater than that of the control at 112 d. RGO also accelerated the dissipation of triclosan, and its degradation products in both treatments and controls were tentatively identified via 14C-labeling method and LC-Q-TOF-MS analysis. The concentrations of the major metabolites (methyl-triclosan and dechlorinated dimer) were inversely related with the concentrations of RGO. RGO at 50 mg kg-1 or lower had a negligible effect on the degradation of triclosan in paddy soil. Triclosan was strongly adsorbed onto RGO-contaminated soil, which may play a vital role in the fate of triclosan in RGO-contaminated paddy soil. Interestingly, RGO had little effect on triclosan-degrading bacteria via soil microbial community analysis. This study helps understand the effects of RGO on the transformation of triclosan in paddy soil, which is of significance to evaluate the environmental risk of triclosan in RGO-contaminated soil.

Injectable conductive and angiogenic hydrogels for chronic diabetic wound treatment.

Chronic diabetic wounds are lack of angiogenesis and susceptible to bacterial infections due to their high sugar microenvironment, making them difficult to heal. Here, a conductive and intrinsically antibacterial hydrogel with pH responsiveness has been developed. This hydrogel has good mechanical properties, self-healing ability and biocompatibility, and can smartly release the pro-angiogenic drug, deferoxamine. Application of the hydrogel promotes the proliferation and migration of endothelial cells and enhances vascularization by upregulating the expression of hypoxia-inducible factor-1α and vascular endothelial growth factor. The hydrogel dressing combined with electrical stimulation improves angiogenesis and significantly accelerates the healing of infected diabetic wounds, which would lead to a promising therapeutic strategy.

Distinct uptake and accumulation profiles of triclosan in youdonger (Brassica campestris subsp. Chinensis var. communis) under two planting systems: Evidence from 14C tracing techniques.

Triclosan is a widely used biocide against microorganisms and is ubiquitously distributed in the environment. Triclosan can be accumulated into plants from soil and hydroponic media. However, little information is currently available on the comparative fate of triclosan in plants under soil and hydroponics cultivation conditions and factors governing uptake. Therefore, this study was designed to comparatively elucidate the uptake mechanism of 14C-triclosan in youdonger (Brassica campestris subsp. Chinensis var. communis) grown under different soils and hydroponics and clarify dominant uptake factors. Results showed that 77.2% of 14C were accumulated in youdonger grown in a hydroponic system, while only 1.24%-2.33% were accumulated in the two soil-planting systems. In addition, the bioconcentration factor (BCF) of 14C-triclosan in soil-plant systems was approximately 400-fold smaller than that in the hydroponics. In the soil-planting system, a strong linear correlation was found between concentrations of triclosan in soil pore water and youdonger plant (R2 > 0.85, p < 0.01) at different incubation times. Therefore, triclosan in pore water might be a good indicator to estimate its accumulation in plants and is significantly affected by soil pH, clay, and organic matter contents. The estimated average dietary intakes of triclosan for youdonger grown in hydroponic and soil-planting systems were estimated to be 1.31 ng day-1 kg-1 and 0.05-0.12 ng day-1 kg-1, respectively, much lower than the acceptable dietary intakes of triclosan (83 µg day-1 kg-1), indicating no significant human health risks from youdonger consumption. This study provided insights into uptake routes of triclosan into youdonger plants from both soil and hydroponic systems, bioavailability of triclosan in different soils, and further assessment of human exposure to triclosan from youdonger.

Single-cell omics: A new direction for functional genetic research in human diseases and animal models.

Over the past decade, with the development of high-throughput single-cell sequencing technology, single-cell omics has been emerged as a powerful tool to understand the molecular basis of cellular mechanisms and refine our knowledge of diverse cell states. They can reveal the heterogeneity at different genetic layers and elucidate their associations by multiple omics analysis, providing a more comprehensive genetic map of biological regulatory networks. In the post-GWAS era, the molecular biological mechanisms influencing human diseases will be further elucidated by single-cell omics. This review mainly summarizes the development and trend of single-cell omics. This involves single-cell omics technologies, single-cell multi-omics technologies, multiple omics data integration methods, applications in various human organs and diseases, classic laboratory cell lines, and animal disease models. The review will reveal some perspectives for elucidating human diseases and constructing animal models.

Self-doping of molecular quantum-dot cellular automata: mixed valence zwitterions.

Molecular quantum-dot cellular automata (QCA) is a promising paradigm for realizing molecular electronics. In molecular QCA, binary information is encoded in the distribution of intramolecular charge, and Coulomb interactions between neighboring molecules combine to create long-range correlations in charge distribution that can be exploited for signal transfer and computation. Appropriate mixed-valence species are promising candidates for single-molecule device operation. A complication arises because many mixed-valence compounds are ions and the associated counterions can potentially disrupt the correct flow of information through the circuit. We suggest a self-doping mechanism which incorporates the counterion covalently into the structure of a neutral molecular cell, thus producing a zwitterionic mixed-valence complex. The counterion is located at the geometrical center of the QCA molecule and bound to the working dots via covalent bonds, thus avoiding counterion effects that bias the system toward one binary information state or the other. We investigate the feasibility of using multiply charged anion (MCA) boron clusters, specifically closo-borate dianion, as building blocks. A first principle calculation shows that neutral, bistable, and switchable QCA molecules are possible. The self-doping mechanism is confirmed by molecular orbital analysis, which shows that MCA counterions can be stabilized by the electrostatic interaction between negatively charged counterions and positively charged working dots.

Does CT evidence of a flat inferior vena cava indicate hypovolemia in blunt trauma patients with solid organ injuries?

BACKGROUND: Nonoperative management for selective patients with solid organ injuries from blunt trauma has gained wide acceptance. However, for trauma surgeons, it is often difficult to estimate a patient's circulatory volume. Some authors have proposed that the presence of a collapsed inferior vena cava (IVC) on computed tomography (CT) scan correlates with inadequate circulatory volume. Our aim was to verify whether CT evidence of a flat IVC (FI) is an indicator of hypovolemia in blunt trauma patients with solid organ injuries. METHODS: We conducted a retrospective chart review of all blunt trauma patients with solid organ injuries admitted to our Medical Center from July 2003 to September 2006. Of the 226 patients reviewed, 29 had CT evidence of FI. We compared Injury Severity Scores, hemodynamic parameters, fluid and blood transfusion requirements, mortality rate, and hospital course between patients with (FI group) and without FI (non-FI [NFI] group). RESULTS: The FI group had higher rates of intensive care unit admission and mortality, in addition to longer intensive care unit stays, when compared with the NFI group. In addition, the patients in the FI group needed larger amounts of fluid and blood transfusions and presented lower hemoglobin levels during the first week of admission; furthermore, the majority deteriorated to a state of shock in the emergency department. CONCLUSIONS: CT evidence of FI is a good indicator of hypovolemia and an accurate predictor for prognosis in trauma patients with blunt solid organ injuries.