It can be unnecessary to combine common synovial fluid analysis and alpha-defensin tests for periprosthetic joint infection diagnosis.

BACKGROUND: Periprosthetic joint infection is a serious complication after total joint arthroplasty. Despite that alpha-defensin was used as diagnostic test in the 2018 ICM (international consensus meeting) criteria, its position in the PJI diagnostic pipeline was controversial. Therefore, we performed a retrospective pilot study to identify whether synovial fluid alpha-defensin test was necessary when corresponding synovial fluid analysis (WBC count, PMN% and LE tests) was performed. METHODS: Between May 2015 and October 2018, a total of 90 suspected PJI patients who underwent revisions after TJA were included in this study. Based on the 2018 ICM criteria, the interobserver agreements between preoperative diagnostic results and postoperative diagnostic results and the interobserver reliability between preoperative diagnostic results and postoperative diagnostic results with or without synovial fluid alpha-defensin tests were calculated. After that, the ROC analysis, and the direct cost-effectiveness of adding alpha-defensin was performed. RESULTS: There were 48,16 and 26 patients in the PJI group, inconclusive group and non-PJI group, respectively. Adding the alpha-defensin tests into 2018 ICM criteria can't change the preoperative diagnostic results, postoperative diagnostic results, and the concordance between preoperative and postoperative diagnostic results. Moreover, the Risk-benefit Ratio is over 90 per changed decision and the direct cost-effectiveness of alpha-defensin was more than $8370($93*90) per case. CONCLUSIONS: Alpha-defensin assay exhibit high sensitivity and specificity for PJI detection as a standalone test based on the 2018 ICM criteria. However, the additional order of Alpha-defensin can't offer additional evidence for PJI diagnosis when corresponding synovial fluid analysis was performed (synovial fluid WBC count, PMN% and LE strip tests). EVIDENCE LEVEL: Level II, Diagnostic study.

Molecular characteristics, polymorphism and expression analysis of mhc â ¡ in yellow catfish(pelteobagrus fulvidraco)responding to Flavobacterium columnare infection.

The major histocompatibility complex (MHC) is an important component of the immune system of vertebrates, which plays a vital role in presenting extrinsic antigens. In this study, we cloned and characterized the mhc ⅡA and mhc ⅡB genes of yellow catfish Pelteobagrus fulvidraco. The open reading frames (ORFs) of mhc ⅡA and mhc ⅡB genes were 708 bp and 747bp in length, encoding 235 and 248 amino acids, respectively. The structure of mhc ⅡA and mhc ⅡB includes a signal peptide, an α1/ß1 domain, an α2/ß2 domain, a transmembrane region and a cytoplasmic region. Homologous identity analysis revealed that both mhc ⅡA and mhc ⅡB shared high protein sequence similarity with that of Chinese longsnout catfish Leiocassis longirostris. mhc ⅡA and mhc ⅡB showed similar expression patterns in different tissues, with the higher expression level in spleen, head kidney and gill and lower expression in liver, stomach, gall bladder and heart. The mRNA expression level of mhc ⅡA and mhc ⅡB in different embryonic development stages also showed the similar trends. The higher expression was detected from fertilized egg to 32 cell stage, low expression from multicellular period to 3 days post hatching (dph), and then the expression increased to a higher level from 4 dph to 14 dph. The mRNA expression levels of mhc ⅡA and mhc ⅡB were significantly up-regulated not only in the body kidney and spleen, but also in the midgut, hindgut, liver and gill after challenge of Flavobacterium columnare. The results suggest that Mhc Ⅱ plays an important role in the anti-infection process of yellow catfish P. fulvidraco.

Reconstruction of Paprosky Type III Acetabular Defects by Three-Dimensional Printed Porous Augment: Techniques and Clinical Outcomes of 18 Consecutive Cases.

OBJECTIVE: To introduce the surgical technique of reconstruction of Paprosky type III acetabular defects by 3D printed porous augments. METHODS: First, CT scans of pelvis were obtained to establish the 3D reconstruction model of 3D printed porous augment. Then, a nylon pelvis model was printed to simulate operation with the surgeons. At this time, the augment was designed and modified according to the surgeon's suggestions and the 3D printing principles. Eighteen patients with Paprosky type III acetabular defects receiving reconstructive surgery by 3D printed porous augments were included in current study. Their data, including general information, intra-operative findings, imaging results, functional scores, and complications were retrospectively analyzed. RESULTS: The mean follow-up time lasted 33.3 ± 2.0 (24-56) months. The average limb-length discrepancy (LLD) was 31.7 ± 4.2 (3-59) mm preoperatively, 7.7 ± 1.4 (1-21) mm postoperatively (P < 0.0001), and 7.5 ± 1.2 (0-18) mm at the latest follow-up. The mean vertical position of hip center of rotation (HCOR) from the interteardrop line changed from preoperative 50.7 ± 3.9 (23.3-75.3) mm to postoperative 22.9 ± 1.9 (10.1-40.3) mm (P < 0.0001), with the latest follow-up revealing an HCOR of 22.3 ± 1.7 (11.0-40.5) mm. Follow-up study showed that no hip had radiolucencies and radiological loosening of the acetabular components and augment. The average Harris hip score (HHS) improved from 40.3 ± 4.5 (10.5-71) before operation to 88.4 ± 1.9 (75-97) at the last follow-up (P < 0.0001). Moreover, follow-up exhibited that no periprosthetic joint infection, hip dislocation, fracture, and re-revision occurred. CONCLUSION: Surgical treatment of Paprosky type III acetabular defect with 3D printed porous augment was simple, achieved good match between porous augment and the defect bone surface and the acetabular component, ideally restored LLD and HCOR after operation, significantly improved HHS and attained good early clinical outcomes. It is a promising personalized solution for patients with severe acetabular bone defect.

Meta-analysis of synovial fluid polymerase chain reaction for diagnosing periprosthetic hip and knee infection.

BACKGROUND AND OBJECTIVE: The purpose of this study was to estimate the diagnostic performance of synovial fluid polymerase chain reaction (PCR) in periprosthetic hip and knee infection, and whether synovial fluid PCR has greater diagnostic significance than conventional methods. METHODS: The literature databases PubMed, Scopus, and the Web of Science were searched for English articles describing periprosthetic joint infection (PJI) diagnosis by synovial fluid PCR. Articles were limited to the period between January 1990 and December 2019. Subsequently, conventional methods that were used on at least two occasions were included for further analysis. Data analysis was performed using the Meta-DiSc and Stata software. RESULTS: Eleven studies with 1360 cases were included in the meta-analysis. The pooled sensitivity, specificity, and diagnostic odds ratio (DOR) of synovial fluid PCR were 0.70 (95% CI 0.66-0.74), 0.92 (95% CI 0.90-0.93), and 37.4 (95% CI 17.77-78.74), respectively. CONCLUSIONS: Synovial fluid PCR provides an effective tool for rapid diagnosis of PJI, and also in the early stages of culture-negative bacterial infections.

Molecular characterization and expression analysis of Tf_TLR4 and Tf_TRIL in yellow catfish Tachysurus fulvidraco responding to Edwardsiella ictaluri challenge.

Toll-like receptors play significant roles in defensing against pathogen invasion. In this study, TLR4 and TRIL from Yellow catfish Tachysurus fulvidraco (Tf), were identified and characterized. The open reading frames of the Tf_TLR4 and Tf_TRIL genes were 2466 bp and 1827 bp in length, encoding 821 and 608 amino acids, respectively. The Tf_TLR4 consists of LRRs, a transmembrane domain and a TIR domain, and Tf_TRIL only contains LRRs and TIR domain. Homologous identity revealed that both Tf_TLR4 and Tf_TRIL have high protein sequence similarity with that of channel catfish Ictalurus punctatus. Both the Tf_TLR4 and Tf_TRIL genes were highly expressed in head kidney and brain, respectively. The mRNA expression levels of Tf_TLR4 and Tf_TRIL genes were up-regulated in intestine and immune-related tissues after challenge of Edwardsiella ictaluri. The microscopic observation of the gut showed that the pathological changes in midgut and hindgut are more obvious than that in foregut after challenged with E. ictaluri. These results indicate that these two genes play potential roles in the host defense against E. ictaluri invasion. This study will provide valuable information to better understand the synergistic roles of TLR4 and TRIL in the innate immune system of yellow catfish and other fish.

Dietary Glycyrrhiza uralensis extracts supplementation elevated growth performance, immune responses and disease resistance against Flavobacterium columnare in yellow catfish (Pelteobagrus fulvidraco).

The present study was conducted to evaluate the influence of Glycyrrhiza uralensis (G. uralensis) extracts on the growth performance, histological structure, immune response and disease resistance against Flavobacterium columnare (F. columnare) of yellow catfish. Fish were fed with two different diets, i.e., basal diet as control group (CG) and diet containing G. uralensis extracts as experimental group (GG). After 60 days feeding, growth performance of GG fish was significantly improved, with increased WG and SGR but decreased FCR compared to CG fish. Fish were then challenged with F. columnare for two times, as fish showed rare mortality after the first infection. GG fish showed significantly lower cumulative mortality during F. cloumnare infection than CG fish after 21 days infection (dpi). Epithelial cell exfoliation and obvious cellular vacuolization in the skin and congestion of gill lamellae were detected in CG fish, while GG fish showed increased width of epidermis and mucous cells number in skin, and increased length of secondary lamina in gill. GG fish also exhibited higher enzyme activity of lysozyme in serum and mRNA expression of lysozyme in head kidney than CG fish at most time points post infection. G. uralensis extracts supplementation also induced earlier serum anti-oxidative responses, with increased superoxide dismutase activity and total antioxidant capacity in GG fish at 1 dpi. Compared to CG fish, GG fish showed increased expression level of genes involved in TLRs-NFκB signaling (TLR2, TLR3, TLR5, TLR9, Myd88, and p65NFκB), resulting in higher expression levels of pro-inflammatory cytokines (IL-1ß and IL-8) in the head kidney post infection. However, these genes showed deviation in the gill of GG fish, which increased at some time points but decreased at other time points. Moreover, G. uralensis extracts supplementation also significantly unregulated the expression levels of IgM and IgD in head kidney, and the expression levels of IgM in the gill of yellow catfish, suggesting the elevated humoral immune response during F. columnare infection. All these results contributed to the elevated disease resistance ability against F. cloumnare infection of yellow catfish after dietary G. uralensis extracts supplementation.

Study of transpedicular screw fixation on spine development in a piglet model.

BACKGROUND: Transpedicular screws may cause damage to the cartilage in the neural arch of the vertebra, and give continuous pressure to the skeleton besides the vertebral body. The aim of this study is to examine the morphological change of the vertebral body at fixation sites and development of the vertebral body after fixation. METHODS: A piglet model was used to study the influence of transpedicular screw fixation on spine development. Transpedicular screw fixation was adjusted to meet specific requirements of surgery on piglet. The screws and plates were placed at L1-L3 vertebral plates via routine surgical approach. Scoliosis and kyphosis Cobb angles were measured. RESULTS: Anatomical characteristics of 6-week-old piglets fit the transpedicular screw system, and can meet the requirements of related studies. Transpedicular screw fixation system has no significant influence on the development of canalis vertebralis. Fixation did not cause developmental stenosis of canalis vertebralis and damage to spinal cord or nerve root. However, transpedicular screw fixation significantly impacted the development of the spine: it shortened the spine by curtailing the length of the vertebral body and intervertebral space. Our results also suggested that slow growth of epiphyseal plate may contribute to the shortening of the vertebral body. CONCLUSION: Transpedicular screw fixation system is beneficial for fixation of the developing spine. It may not cause scoliosis but could lead to change of cervical curvature.