Safety and efficacy of mezlocillin: a single-drug therapy for penetrating abdominal trauma

This study was done to determine if a single drug, mezlocillin (Mezlo), is as safe and as effective as combined clindamycin (Clind) and gentamicin (Gent) in the treatment of penetrating abdominal wounds. One hundred seventy-three patients received either Mezlo or Clind/Gent combined therapy as assigned by computer-generated randomization. Of these, 147 patients were evaluable. Of 73 patients treated with Clind/Gent the mean duration of hospital stay was 8.9 +/- 4.0 days. Infectious complications developed in 18 patients of whom five failed to respond promptly, but only one required change in therapy. Of 74 patients treated with Mezlo, the mean duration of hospital stay was 9.1 +/- 5.0 days. Infectious complications occurred in 17, in whom four patients failed to eliminate their infections, and two needed changes in antibiotic therapy. None of the patients in either antibiotic group failed because of Enterococcus or Pseudomonas infections. There were no deaths. Twelve isolates of Bacteroides were found in peritoneal fluid cultures and all these patients had colon injuries. The overall therapeutic response was excellent to good in 94% on Clind/Gent and 93% on Mezlo. Azotemia developed in one patient on Clind/Genet and one on Mezlo but no other adverse reactions occurred. The differences shown between the two groups were not statistically significant. We conclude that a single drug mezlocillin is as safe and as effective in the treatment of abdominal trauma as combined clindamycin and gentamicin.     

南京“5.7”192Ir源放射事故患者眼晶状体和眼底的改变

目的 根据对1例意外受到¹⁹²Ir源外照射患者的眼晶状体和视网膜改变的动态随访观察,总结放射性损伤所致相关眼晶状体及视网膜改变的特点,为临床核事故患者的眼科诊治和预后判断提供客观的诊断经验和依据。方法 对患者的眼晶状体和视网膜进行视力、裂隙灯、自动视野分析仪、眼底光学相干断层(OCT)扫描、眼底照相、眼底血管造影等形态功能检查,并密切坚持随访20个月,对检查结果进行对比分析。结果 患者在受辐射后1个月首诊时,双眼视力均为1.0,眼晶状体周边皮质轻微老年性浑浊性变化,眼底未见异常。20个月后随访检查,视力下降(约0.6),右眼晶状体皮质区可见明显粉末状和点状浑浊,后极区后囊及其下亦出现轻微局限浑浊灶;右眼视野颞上方缺损及鼻下方出现局部暗点;黄斑部中心凹厚度变化不大,眼底检查及造影和OCT扫描均证明和提示双眼已有视神经部分轻度萎缩改变,双眼玻璃膜疣,视盘颜色较淡,双眼眼底造影可见点状或絮状渗漏。结论 放射性辐射可以引起或加重眼晶状体浑浊,其形态特征可以不限于后囊下及后极区白内障,也可以是在皮质层内形成非冠状分布的点状浑浊。此外,视网膜和视神经也可以发生损伤。值得注意的是,即使受辐射后早期眼部检查正常,后期也会出现这些病理改变。     

General 2.5 power law of metallic glasses

Metallic glass (MG) is an important new category of materials, but very few rigorous laws are currently known for defining its “disordered” structure. Recently we found that under compression, the volume (V) of an MG changes precisely to the 2.5 power of its principal diffraction peak position (1/q₁). In the present study, we find that this 2.5 power law holds even through the first-order polyamorphic transition of a Ce₆₈Al₁₀Cu₂₀Co₂ MG. This transition is, in effect, the equivalent of a continuous “composition” change of 4f-localized “big Ce” to 4f-itinerant “small Ce,” indicating the 2.5 power law is general for tuning with composition. The exactness and universality imply that the 2.5 power law may be a general rule defining the structure of MGs.Metallic glasses (MGs) possess many unique and superior properties, such as extremely high strength, hardness, and corrosion resistance, etc., making them promising metallic materials with widespread applications (1, 2). Thousands of MGs with a wide range of compositions and properties have been synthesized over the past decades. However, so far the development of MGs is mainly based on tedious composition mapping in multicomponent space to pinpoint the combination of elements with optimized glass-forming ability (GFA). This method for development of MGs is a time- and resource-intensive strategy of trial and error which highlights the need for the guidance of a general theory (2, 3). Intensive research effort has been devoted to finding general rules in various MGs to understand the fundamentals and to guide the development of new MGs (4, 5). Quantitative correlations between their properties have been observed. For instance, compressive yield strength and elastic moduli of MGs are found to be intimately connected with their glass transition temperature T_g (6–10), and the ductility, fragility (11, 12), and Poisson’s ratio of MGs are closely related (13–16). The extensive correlations in properties suggest that the disordered MGs may share general rules in their structure. To clarify this scenario, detailed and accurate structural information spanning short range to long range is required. However, the current experimental probes and theories are limited to local structure in MGs (17). Therefore, understanding how the atoms efficiently fill up the 3D space and how this controls the bulk properties of MGs remains a long-standing theoretical challenge (18–23). To date, few general and exact rules regarding structure–property relationships have been established in MGs (23).Encouraging progress on understanding structure–property relationships in MGs has recently been made through the discoveries of the noncubic (2.3 or 2.5) power laws that correlate the principal diffraction peak (PDP) position q₁ with the bulk density ρ or average atomic volume, V_a, i.e., ρ∝(q₁)^D or V_a∝(1/q₁)^D, where D equals ∼2.3 with varying the composition of MGs at ambient pressure (19) or ∼2.5 for tuning the density of MGs with pressure (22, 24). Whereas composition and pressure show similar exponents in the power laws in MGs, composition and pressure are two independent variables for controlling the density (volume) of materials; they usually have dramatically different effects on MGs. For example, pressure is thought to cause only elastic densification in MGs without obvious structural change because of their already densely packed structure; the structure and properties of MGs are very sensitive to even minor compositional variations (25, 26). In addition, to achieve composition change, different samples usually have to be synthesized. And, many other variables are thought to be inevitably involved, making the compositional change complex (23). Therefore, some basic questions have been perplexing to the glass community: Why do “complex” compositional and “simple” pressure power laws show similar exponents? Is there any connection between them? These questions remain unanswered and have been the major obstacle in understanding the nature of these noncubic power laws.To address these questions, a systematic study in the 2D pressure-composition space seems to be required. However, the consistency of the data in this kind of study will be questionable. Alternatively, in the present study, we choose the polyamorphous Ce₆₈Al₁₀Cu₂₀Co₂ MG as a model system. It is well known that Ce-based MG systems show a polyamorphic transition between ∼2 GPa and ∼5 GPa caused by the pressure-induced 4f electron localized-to-itinerant transition (27, 28). During this polyamorphic transition, both the atomic size and the electronegativity of Ce are significantly changed (29). Composition tuning in MGs mainly means the variation of atomic size and electronegativity of components, which controls the formation of MGs (30). Therefore, although nothing changes in the nucleus, for MGs this pressure-induced polyamorphic transition is equivalent to a continuous “composition” change with the 4f-localized “big Ce” gradually substituted by 4f-itinerant “small Ce.” As a result, we are able to vary both pressure and composition of a MG in a well-controlled way for the first time, to our knowledge.     

Characterizing the binding interaction of astilbin with bovine serum albumin: a spectroscopic study in combination with molecular docking technology

Astilbin (ASN) is a flavonoid compound isolated from the rhizome of Smilax china L. (Smilacaceae). It has many bioactivities, such as selective immunosuppression, antioxidant, anti-hepatic injury, etc., and is widely used in traditional Chinese medical treatments. The interaction of ASN with bovine serum albumin (BSA) was studied in a physiological buffer (pH = 7.40) using multi-spectroscopic techniques in combination with molecular docking methods. UV-vis absorption measurements proved that a ASN–BSA complex could be formed. Fluorescence data revealed that ASN could strongly quench the intrinsic fluorescence of BSA in terms of a static quenching procedure. The process of binding was spontaneous and the binding occurred mainly through hydrogen bonding and van der Waals forces. The distance r between donor (BSA) and acceptor (ASN) was calculated to be 4.80 nm based on Förster''s non-radiative energy transfer theory. The binding constant (K_a = 7.31 × 10⁴ mol L⁻¹) and the number of binding sites (n ≈ 1) at 298 K suggested that ASN only occupied one site in BSA with high affinity. Moreover, the results of molecular docking indicated that ASN was more likely to be located in site I (sub-domain IIA) of BSA. The results of synchronous fluorescence and three-dimensional fluorescence spectra showed that ASN induced conformational changes of BSA. The findings would be beneficial for research on the transportation, distribution and some important bioactivities of ASN in the human body.

The interaction of astilbin with bovine serum albumin was confirmed by multi-spectroscopic techniques and molecular docking methods.     

High voltage,solvent-free solid polymer electrolyte based on a star-comb PDLLA–PEG copolymer for lithium ion batteries

In this work, a novel star-comb copolymer based on poly(d,l-lactide) (PDLLA) macromonomer and poly(ethylene glycol)methyl ether methacrylate (PEGMA) was prepared, and the electrochemical properties were studied, with the aim of using it as a solid polymer electrolyte in lithium ion batteries. The six-arm vinyl functionalized PDLLA macromonomer was synthesized by a ring-opening polymerization (ROP) of d,l-lactide and subsequently an acylation of the hydroxy end-groups. A series of free-standing solid polymer electrolyte membranes from different ratios of PDLLA, PEGMA and LiTFSI were prepared through solvent-free free radical polymerization under UV radiation. The chemical structure of the obtained polymers was confirmed by ¹H NMR and FTIR. The as-prepared six-arm star-comb solid polymer electrolytes (PDLLA-SPEs) exhibit good thermal stability with T_d^5%s of ∼270 °C and low T_gs of −48 to −34 °C. The electrochemical characterization shows that the PDLLA-SPEs possess a wide electrochemical window up to 5.1 V with an optimal ionic conductivity of 9.7 × 10⁻⁵ S cm⁻¹ at 60 °C at an EO/Li⁺ ratio of 16 : 1. Furthermore, the all-solid-state LiFePO₄/Li cells display extraordinary cycling and rate performances at 60 °C by curing the PDLLA-SPEs directly on the cathode. These superior properties of the six-arm star-comb PDLLA-SPE make it a promising candidate solid electrolyte for lithium batteries.

In this work, a novel star-comb copolymer based on PDLLA macromonomer and PEGMA was prepared, and the electrochemical properties were studied, with the aim of using it as a solid polymer electrolyte in lithium ion batteries.     

Benefits of Less Restrictive Regulation of Advance Practice Registered Nurses in Florida

Background

Advanced Practice Registered Nurses (APRNs) provide access to cost-effective, high quality care. APRNs are underutilized in states that restrict their practice. Removing restrictions could expand access to quality health care, cost-effectively relieve the physician shortage, and contribute economically.

Anti-inflammatory effects of hinokitiol on human corneal epithelial cells: an in vitro study

Purpose

This study assessed the anti-inflammatory effect and mechanism of action of hinokitiol in human corneal epithelial (HCE) cells.

Methods

HCE cells were incubated with different concentrations of hinokitiol or dimethylsulfoxide (DMSO), which served as a vehicle control. Cell viability was evaluated using Cell Counting Kit-8 (CCK-8) assay. After polyriboinosinic:polyribocytidylic acid (poly(I:C)) stimulus, cells with or without hinokitiol were evaluated for the mRNA and protein levels of interleukin-8 (IL-8), interleukin-6 (IL-6), and interleukin-1β (IL-1β) using real-time PCR analysis and an enzyme-linked immunosorbent assay (ELISA), respectively. Nuclear and cytoplasmic levels of nuclear factor kappa B (NF-κB) p65 protein and an inhibitor of NF-κB α (IκBα) were evaluated using western blotting.

Results

There were no significant differences among the treatment concentrations of hinokitiol compared with cells incubated in medium only. Incubating with 100 μM hinokitiol significantly decreased the mRNA levels of IL-8 to 58.77±10.41% (P<0.01), IL-6 to 64.64±12.71% (P<0.01), and IL-1β to 54.19±8.10% (P<0.01) compared with cells stimulated with poly(I:C) alone. The protein levels of IL-8, IL-6, and IL-1β had similar trend. Further analysis revealed that hinokitiol maintained the levels of IκBα and significantly reduced NF-κB p65 subunit translocation to the nucleus which significantly inhibiting the activation of the NF-κB signal pathway.

Conclusion

Hinokitiol showed a significant protective effect against ocular surface inflammation through inhibiting the NF-κB pathway, which may indicate the possibility to relieve the ocular surface inflammation of dry eye syndrome (DES).     

High performance sol–gel synthesized Ce0.9Sr0.1(Zr0.53Ti0.47)O4 sensing membrane for a solid-state pH sensor

In this paper, we developed a high-performance solid-state pH sensor using a Ce_0.9Sr_0.1(Zr_0.53Ti_0.47)O₄ (CSZT) membrane through a very simple sol–gel spin-coating process. The structural properties of the CSZT membrane are correlated with its sensing characteristics. The CSZT based EIS sensor exhibited a high pH sensitivity of 92.48 mV pH⁻¹, which is beyond the Nernst limit (59.4 mV pH⁻¹), and good reliability in terms of a low hysteresis voltage of 1 mV and a small drift rate of 0.15 mV h⁻¹. This behaviour is attributed to the incorporation of Sr in the CSZT sensing membrane, which promotes change in the Ce oxidation state from Ce⁴⁺ to Ce³⁺.

We developed a high-performance solid-state pH sensor using a Ce_0.9Sr_0.1(Zr_0.53Ti_0.47)O₄ (CSZT) membrane through a very simple sol–gel spin-coating process.