Failure of volar locking plate fixation of an extraarticular distal radius fracture: A case report

<p>Abstract</p> <p>Background</p> <p>Volar locking plates provide significant structural stability to the distal radius. Failure of a volar locked plating is a rarely reported complication in the literature.</p> <p>Case Presentation</p> <p>A 40 year-old, obese female patient who presented with a displaced extraarticular distal radius fracture, underwent open reduction and internal fixation of the fracture using a volar locking plate. Radiographs taken at 10 weeks postoperatively showed failure of fixation with breakage of the four distal locking screws. A hardware removal was performed at 6 months, and the patient was then lost to follow-up. She presented again at 18 months after the first surgery, with significant pain, and radiographic signs of a radial collapse and a fracture-nonunion. A total wrist fusion was performed as the method of choice at that point in time.</p> <p>Conclusion</p> <p>Volar locked plating represents the new "gold standard" of distal radius fracture fixation. However, despite the stability provided by locking plates, hardware failure may occur and lead to a cascade of complications which will ultimately require a wrist fusion, as outlined in this case report. Additional structural support by bone grafting may be needed in selected cases of volar locked plating, particularly in patients with a high risk of developing a fracture-nonunion.</p

Impartial comparative analysis of measurement of leukocyte telomere length/DNA content by Southern blots and qPCR.

Telomere length/DNA content has been measured in epidemiological/clinical settings with the goal of testing a host of hypotheses related to the biology of human aging, but often the conclusions of these studies have been inconsistent. These inconsistencies may stem from various reasons, including the use of different telomere length measurement techniques. Here, we report the first impartial evaluation of measurements of leukocyte telomere length by Southern blot of the terminal restriction fragments and quantitative PCR (qPCR) of telomere DNA content, expressed as the ratio of telomeric product (T)/single copy gene (S) product. Blind measurements on the same samples from 50 donors were performed in two independent laboratories on two different occasions. Both the qPCR and Southern blots displayed highly reproducible results as shown by r values &gt; 0.9 for the correlations between results obtained by either method on two occasions. The inter-assay CV measurement for the qPCR was 6.45%, while that of the Southern blots was 1.74%. The relation between the results generated by Southern blots versus those generated by qPCR deviated from linearity. We discuss the ramifications of these findings with regard to measurements of telomere length/DNA content in epidemiological/clinical circumstances

Boosting Fast Adversarial Training with Learnable Adversarial Initialization

Adversarial training (AT) has been demonstrated to be effective in improving model robustness by leveraging adversarial examples for training. However, most AT methods are in face of expensive time and computational cost for calculating gradients at multiple steps in generating adversarial examples. To boost training efficiency, fast gradient sign method (FGSM) is adopted in fast AT methods by calculating gradient only once. Unfortunately, the robustness is far from satisfactory. One reason may arise from the initialization fashion. Existing fast AT generally uses a random sample-agnostic initialization, which facilitates the efficiency yet hinders a further robustness improvement. Up to now, the initialization in fast AT is still not extensively explored. In this paper, we boost fast AT with a sample-dependent adversarial initialization, i.e., an output from a generative network conditioned on a benign image and its gradient information from the target network. As the generative network and the target network are optimized jointly in the training phase, the former can adaptively generate an effective initialization with respect to the latter, which motivates gradually improved robustness. Experimental evaluations on four benchmark databases demonstrate the superiority of our proposed method over state-of-the-art fast AT methods, as well as comparable robustness to advanced multi-step AT methods. The code is released at https://github.com//jiaxiaojunQAQ//FGSM-SDI.Comment: Accepted by TI

Security-Reliability Tradeoff Analysis for Underlay Cognitive Two-Way Relay Networks

We consider an underlay wiretap cognitive two-way relay network (CTWRN), where two secondary sources exchange their messages via multiple secondary decode-and-forward digital network coding relays in the presence of an eavesdropper by using a three-phase time division broadcast protocol and sharing the licensed spectrum of primary users. To mitigate eavesdropping attacks, an artificial noise (AN)-aided opportunistic relay selection scheme, called generalized max-min (GMM) relay selection is proposed to enhance physical layer security for the wiretap CTWRNs. The performance of the GMM scheme is analyzed, and evaluated by the exact closed-form outage probability and intercept probability. Additionally, we also provide asymptotic approximations for the outage probability and intercept probability at high signal-to-noise ratio. For comparison, we analyze the performance of the conventional max-min (MM) relay selection scheme as well. It is shown that the GMM scheme outperforms the MM scheme in terms of the security-reliability tradeoff (SRT), where the security and reliability are quantified by the intercept probability and outage probability, respectively. Moreover, the SRTs of the MM and GMM schemes can be substantially improved by increasing the number of secondary relays, while the improvement of the GMM scheme is more evident than that of the MM scheme

Prior-Guided Adversarial Initialization for Fast Adversarial Training

Fast adversarial training (FAT) effectively improves the efficiency of standard adversarial training (SAT). However, initial FAT encounters catastrophic overfitting, i.e.,the robust accuracy against adversarial attacks suddenly and dramatically decreases. Though several FAT variants spare no effort to prevent overfitting, they sacrifice much calculation cost. In this paper, we explore the difference between the training processes of SAT and FAT and observe that the attack success rate of adversarial examples (AEs) of FAT gets worse gradually in the late training stage, resulting in overfitting. The AEs are generated by the fast gradient sign method (FGSM) with a zero or random initialization. Based on the observation, we propose a prior-guided FGSM initialization method to avoid overfitting after investigating several initialization strategies, improving the quality of the AEs during the whole training process. The initialization is formed by leveraging historically generated AEs without additional calculation cost. We further provide a theoretical analysis for the proposed initialization method. We also propose a simple yet effective regularizer based on the prior-guided initialization,i.e., the currently generated perturbation should not deviate too much from the prior-guided initialization. The regularizer adopts both historical and current adversarial perturbations to guide the model learning. Evaluations on four datasets demonstrate that the proposed method can prevent catastrophic overfitting and outperform state-of-the-art FAT methods. The code is released at https://github.com/jiaxiaojunQAQ/FGSM-PGI.Comment: ECCV 202

The effects of extracts of atractylodes macrocephala koidz combined with transcutaneous electrical acupoint stimulation in treating the ovariectomized female rats

Background: The present study was to explore the effects of the extracts of Atractylodes macrocephala Koidz (EAMK) combined with transcutaneous electrical acupoint stimulation (TEAS) on the ovariectomized female rats.Materials and Methods: Forty female Sprague-Dawley rats were randomly divided into four groups: sham-operation, model, livial and EAMK+TEAS groups (n=10 in each group). After the individual treatments for 8 weeks ended, the serum levels of estradiol (E2), follicle stimulating hormone (FSH), luteinizing hormone (LH), osteocalcin and interleukin-6 (IL-6) were measured with commercial enzyme-linked immunosorbent assay.Results: We found that in the sham-operation group, the serum E2 and osteocalcin levels were significantly higher, and the serum levels of FSH, LH and IL-6 were markedly lower than those of other groups (P&lt;0.05). No significant differences existed between the livial and EAMK+TEAS groups on the serum E2 and osteocalcin levels (P&gt;0.05), however, the serum FSH and IL-6 levels of EAMK+TEAS group were significantly lower than those of the livial group (P&lt;0.05).Conclusion: EAMK combined with TEAS has promises in treating the ovariectomized female rats.Key words: Extracts of Atractylodes macrocephala Koidz (EAMK), transcutaneous electrical acupoint stimulation (TEAS), osteocalcin, interleukin-6 (IL-6)