Gentamicin-Coated Tibia Nail in Fractures and Nonunion to Reduce Fracture-Related Infections: A Systematic Review

The incidence of a fracture-related infection (FRI) can reach 30% of open tibia fractures (OTF). The use of antibiotic-coated implants is one of the newest strategies to reduce the risk of infection in orthopedic surgery. The aim of this study was to investigate the efficacy and safety of a gentamicin-coated tibia nail in primary fracture fixation (FF) and revision surgery (RS) of nonunion cases in terms of FRI incidence. We conducted a systematic review according to the PRISMA checklist on Pub-Med, Cochrane, and EMBASE. Of the 32 studies, 8 were included, for a total of 203 patients treated: 114 were FF cases (63% open fractures) and 89 were RS cases, of which 43% were infected nonunion. In the FF group, four FRI were found (3.8%): three OTF (Gustilo-Anderson III) and one closed fracture; bone healing was achieved in 94% of these cases. There were four relapses of infection and one new onset in the RS group; bone healing occurred in 88% of these cases. No side effects were found. There were no significant differences in terms of FRI, nonunion, and healing between the two groups. Gentamicin-coated tibia nail is an effective therapeutic option in the prophylaxis of high-risk fracture infections and in complex nonunion cases.     

Magnetic resonance imaging: application in musculoskeletal infection

Forty-two patients with clinically suspected osteomyelitis were examined using magnetic resonance imaging (MRI). Twenty-seven patients (64%) had previous surgery or fracture, and 15 (36%) were referred for differentiation of acute osteomyelitis from bone tumors or other pathologic conditions. MRI was compared with computed tomography in 12 cases and with 111In-labeled leukocytes scans in 22. With MRI, 92% of proved infections were detected, and bone and soft-tissue changes were more evident than with routine radiographs, tomography, or computed tomography. In patients with negative cultures and no previous surgery or fracture, it was difficult for MRI to differentiate operative changes from infection. In these patients, 111In-labeled leukocyte images were more specific than MRI.     

Bioinspired Artificial Nanodecoys for Hepatitis B Virus

A facile route is presented for fabricating a new class of nanomimics that overexpress hepatitis B virus (HBV) receptor by a natural biosynthetic procedure against HBV infection. A nine‐transmembrane HBV‐specific receptor, human sodium taurocholate co‐transporting polypeptide (hNTCP), was engineered to naturally immobilize it onto the cellular surface and subsequently trigger the budding of hNTCP‐anchoring membrane vesicles (hNTCP‐MVs) that favor the HBV virion. hNTCP‐MVs could rapidly block HBV infection in cell models. Furthermore, hNTCP‐MVs treatment could effectively prevent viral infection, spreading, and replication in a human‐liver‐chimeric mouse model of HBV infection. Our findings demonstrate the receptor‐mediated antiviral effect of hNTCP‐MVs to trick HBV and offer novel opportunities for further development of antiviral strategies in nanomedicine.     

新生儿TORCH感染与全血14种微量元素的研究

为了解TORCH感染新生儿全血14种微量元素的分布情况，采用日本岛津ICPQ-1012型高频等离子体发射光谱仪进行了全血14种微量元素的测定；采用深圳市萃智生物工程有限公司TORCH IgM抗体ELISA检测试剂盒检测了TORCH IgM抗体；以正常新生儿为对照组，观察了TORCH感染新生儿全血微量元素的改变。结果表明，HSV感染组，血镁、血锌、血铁低于正常，血铅、血铜、血锰高于正常；风疹病毒感染组，血锰、血锌低于正常，血铜高于正常；弓形虫感染组，血锌、血铁低于正常，血铜、血锰高于正常。提示TORCH感染新生儿全血14种微量元素存在不同类型的微量元素失衡，与各种感染造成机体损害有一定关系，需及时纠正，避免进一步的损害。     

不同品系海带细胞壁组成对褐藻酸降解菌感染响应的差异性

研究了二个品系海带细胞壁的组成在褐藻酸降解菌感染过程中的变化．结果表明，海带荣城1号品系在褐藻酸降解菌感染的初期（前3d），破壁酶对其单细胞或原生质体的相对产率显著降低，而且随着感染时间的延长，相对产率的下降越加明显．3d后，随着感染的继续进行，单细胞或原生质体的相对产率变化不明显．而海带901品系在褐藻酸降解菌感染的整个过程中单细胞或原生质体的相对产率始终没有出现明显的变化，指示海带荣城1号品系细胞壁组成对褐藻酸降解菌感染发生了响应性变化，而海带901品系的细胞壁组成未做出响应变化．研究结果进一步表明，褐藻酸降解菌感染过程中海带荣城1号细胞壁组成的变化主要体现在褐藻胶的变化上，而与纤维素，半纤维素和果胶质成分无关．     

Chi@HMPB@CBD nanocomplexes for laser-assisted therapy of MRSA-infected cutaneous wounds in normal and MKR diabetic mice

The emergence and spreading of methicillin-resistant Staphylococcus aureus (MRSA) have become one of the main reasons for the surgical failure even for the death. Thus, there is an urgent need to develop efficient antimicrobial alternatives for eradicating it so as to improve the therapy efficiency of related diseases. Although the synthesized metal nanoparticles showed the MRSA-killing function in vitro, their biosafety in vivo application is still in controversy due to the potential toxicity and induced multidrug resistance. Recently, plant natural compounds with high antibacterial activity and special mechanisms different from antibiotics have attracted wide interest for developing new anti-MRSA regents. In this work, new nanocomplexes of Chi@HMPB@CBD based on natural compounds of cannabidiol (CBD) and chitosan (Chi) were designed for eradicating MRSA. In vitro results demonstrate that Chi@HMPB@CBD NPs plus laser irradiation can efficiently kill MRSA by inducing bacterial surface perforation, content leakage, ROS production, and ATP reduction. In vivo results show that the combination of Chi@HMPB@CBD NPs plus laser can effectively remove bacteria and accelerate wound healing of MRSA-infected normal and diabetes mellitus mice by up-regulating VEGF and CD31. Moreover, Chi@HMPB@CBD NPs possessing excellent biocompatibility and ultra-low toxicity in vitro significantly delayed the time for multidrug-resistance induction, comparing with silver nanoparticles. In our point, the “green therapeutics” against MRSA show great potential in clinical application.     

Energy-efficient power allocation in cell-free massive MIMO with zero-forcing: First order methods

In this paper, the downlink of cell-free massive multiple-input multiple-output (MIMO) with zero-forcing processing is considered. To maximize the system energy efficiency (EE), we design power allocation algorithms taking into account imperfect channel state information, hardware, and backhaul power consumption. The total EE optimization problem is nonconvex, which traditionally is solved by the successive convex approximation framework which involves second order cone programs (SOCPs). As such methods have high complexity, the run time is extremely long, especially in large-scale systems with thousands of access points (APs) and users. To overcome this problem, in this paper, we propose to apply two computationally efficient methods, namely proximal gradient (PG) method and accelerated proximal gradient (APG) method to solve the considered problem. Numerical results show that, compared to the conventional SOCPs approximation methods, our proposed methods achieve the same performance while the run time is much smaller.     

Stereoselective Synthesis,Configurational Assignment and Biological Evaluations of the Lipid Mediator RvD2n-3 DPA

Herein we report the first total synthesis of RvD2_{n-3 DPA}, an endogenously formed mediator biosynthesized from the omega-3 fatty acid n-3 docosapentaenoic acid. The key steps are the Midland Alpine borane reduction, Sonogashira cross-coupling reactions, and a Z-selective alkyne reduction protocol, yielding RvD2_{n-3 DPA} methyl ester in 13 % yield over 12 steps (longest linear sequence). The physical property data (UV chromophore, chromatography and MS/MS fragmentation) of the synthetic lipid mediator matched those obtained from biologically produced material. Moreover, synthetic RvD2_{n-3 DPA} also carried the potent biological activities of enhancing macrophage uptake of Staphylococcus aureus and zymosan A bioparticles.     

Molecular and genomic characterization of pathogenic traits of group A Streptococcus pyogenes

Group A streptococcus (GAS) or Streptococcus pyogenes causes various diseases ranging from self-limiting sore throat to deadly invasive diseases. The genome size of GAS is 1.85–1.9 Mb, and genomic rearrangement has been demonstrated. GAS possesses various surface-associated substances such as hyaluronic capsule, M proteins, and fibronectin/laminin/immunoglobulin-binding proteins. These are related to the virulence and play multifaceted and mutually reflected roles in the pathogenesis of GAS infections. Invasion of GAS into epithelial cells and deeper tissues provokes immune and non-immune defense or inflammatory responses including the recruitment of neutrophils, macrophages, and dendritic cells in hosts. GAS frequently evades host defense mechanisms by using its virulence factors. Extracellular products of GAS may perturb cellular and subcellular functions and degrade tissues enzymatically, which leads to the aggravation of local and/or systemic disorders in the host. In this review, we summarize some important cellular and extracellular substances that may affect pathogenic processes during GAS infections, and the host responses to these.