Modeling for the estimating the adsorption property of fruit waste-based biosorbents for the removal of organic micropollutants.

The enormous production of fruit waste and the generation of countless organic micropollutants are serious environmental problems. To solve the problems, the biowastes, i.e., orange, mandarin, and banana peels, were used as biosorbents to remove the organic pollutants. In this application, the difficult challenge is knowing the degree of adsorption affinity of biomass for each type of micropollutant. However, since there are numerous micropollutants, it requires enormous material consumption and labor to physically estimate the adsorbability of biomass. To address this limitation, quantitative structure-adsorption relationship (QSAR) models for the adsorption assessment were established. In this process, the surface properties of each adsorbent were measured with instrumental analyzers, their adsorption affinity values for several organic micropollutants were determined through isotherm experiments, and QSAR models for each adsorbent were developed. The results showed that the tested adsorbents had significant adsorption affinity for cationic and neutral micropollutants, while the anionic one had low adsorption. As a result of the modeling, it was found that the adsorption could be predicted for a modeling set with an R2 of 0.90-0.915, and the models were validated via the prediction of a test set that was not included in the modeling set. Also, using the models, the adsorption mechanisms were identified. It is speculated that these developed models can be used to rapidly estimate adsorption affinity values for other micropollutants.

Lymphangitis Carcinomatosa in Neck Soft Tissue: Computed Tomography Findings With Emphasis on Differentiation From Cellulitis.

OBJECTIVE: Lymphangitis carcinomatosa (LC) is a rare form of metastasis. The purposes of this study were to evaluate computed tomography (CT) findings associated with LC in neck soft tissue and to determine those that were useful in distinguishing LC from cellulitis. METHODS: Contrast-enhanced CT images of 26 patients with pathologically confirmed LC (n = 5) and clinically proven cellulitis (n = 21) were reviewed retrospectively. The following CT findings were evaluated and compared between the 2 groups: subcutaneous fat infiltration, enlargement of muscle, thick irregular enhancement of the superficial cervical fascia, grouping of micronodules, focal intramuscular enhancement, localized fluid collection, and nodular skin thickening. RESULTS: Thick irregular enhancement of the superficial cervical fascia (80.0% vs 0%, P < 0.0005), grouping of micronodules (60.0% vs 0%, P < 0.005), and focal intramuscular enhancement (60.0% vs 4.8%, P < 0.05) were significantly more frequent in LC than in cellulitis. Other findings did not show statistical significance between both groups. CONCLUSIONS: When soft tissue swelling is present in the neck with either thick irregular enhancement of the superficial cervical fascia, grouping of micronodules, or focal intramuscular enhancement, the possibility of LC should be considered especially in patients with underlying malignancy.

Simultaneous probing of dual intracellular metabolites (ATP and paramylon) in live microalgae using graphene oxide/aptamer nanocomplex.

The development of an intracellular metabolite imaging platform for live microorganisms has been a challenge in the study of microbes. Herein, we performed metabolite imaging in live microalgal cells using a graphene oxide (GO)/aptamer complex. The properties of the GO were characterized using dynamic light scattering (DLS) and atomic force microscopy (AFM), which were determined to have 140 ± 3 nm in mean diameter. An ATP-specific aptamer was mixed with GO to form a GO/aptamer complex, and the feasibility of the complex was tested in vitro. The high correlation between the fluorescence intensity and concentration of ATP was observed in the range 0-10 mM. Next, the feasibility of the complex was confirmed in vivo. Under both phototrophic and heterotrophic culture conditions, Euglena gracilis internalized the complex, and bright fluorescence was observed as the aptamer was bound to the target metabolite (ATP). The fluorescence intensity of cells was correlated to the ATP concentration in the cells. Imaging of dual intracellular metabolites (ATP and paramylon) was achieved by simply using two different aptamers (ATP-specific aptamer and paramylon-specific aptamer) together, showing the great potential of the complex as a dual-sensing/imaging platform. In addition, the GO/aptamer complex exhibited low cytotoxicity; the proliferation and viability of E. gracilis cells were not significantly affected by the complex. Our results suggested that this new imaging platform can be efficiently used for detecting dual intracellular metabolites in live microalgal cells.

Innovative C-Arm-Free Navigation Technique for Posterior Spinal Fixation for Atlantoaxial Subluxation: A Technical Note.

Study design: Technical note. Objectives: To present a novel C-arm-free technique guided by navigation to insert and place a C1 lateral mass screw. Background and Objectives: Atlantoaxial subluxation (AAS) is a relatively common sequelae in patients with rheumatoid arthritis (RA) and upper cervical trauma. If they present with severe symptoms, surgical intervention such as posterior fusion is indicated. The established treatment for AAS is fixation with a C1 lateral mass screw and C2 pedicle screw (modified Goel technique) to achieve bony fusion. However, this technique requires fluoroscopy for C1 screw insertion. To avoid exposing the operating team to radiation, we present here a novel C-arm-free C1 lateral mass screw insertion technique for AAS. Materials and Methods: A 67-year-old man was referred to our hospital with neck pain, quadriparesis, and clumsiness and numbness of both upper and lower limbs. He had undergone C3-6 posterior fusion previously in another hospital. In physical examination, he had severe muscle weakness of bilateral upper limbs and hypoesthesia of all four limbs. He had hyper-reflexia of bilateral lower limbs and pollakiuria. His Japanese orthopedic score was 8 points out of 17. Preoperative radiograms showed AAS with an atlantodental interval (ADI) of 7 mm. MRI indicated retro-odontoid pseudotumor and severe spinal cord compression at the C1-2 level. The patient underwent posterior atlantoaxial fixation under navigation guidance. To prevent epidural bleeding during the insertion and placement of a C1 lateral mass screw, we have here defined a novel screw insertion technique. Results: The surgical time was clocked as 127 min and blood loss was 100 mL. There were no complications per-operatively or in the postoperative period. The patient showed almost full recovery (JOA 16/17) at two months follow-up and a solid bony fusion was noticed in the radiograms at one year follow-up. Conclusions: This novel surgical procedure and C1 lateral mas screw placement technique is a practical and safe method in recent advances of AAS treatment. Procedurally, the technique helps prevent epidural bleeding from the screw entry point and also allows for proper C1 screw insertion under navigation guidance without exposing surgeons and staff to the risk of fluoroscopic radiation.

Aronia melanocarpa (Black Chokeberry) Reduces Ethanol-Induced Gastric Damage via Regulation of HSP-70, NF-κB, and MCP-1 Signaling.

Aronia melanocarpa (Michx.) Ell. belongs to the Rosaceae family. The purpose of this study is to explore the gastroprotective effect of the Aronia melanocarpa hydro-alcoholic extract (AMHAE) against ethanol-induced gastric ulcer in a rat model. Different concentrations (50, 100, and 200 mg/kg) of AMHAE, or 30 mg/kg of omeprazole, significantly inhibited the gastric injury formation. The ethanol-induced ulcer group showed significant increases of malondialdehyde (MDA), myeloperoxidase (MPO), tumor necrosis factor (TNF)-α, nuclear factor-kappaB p65 (NF-κB p65), and monocyte chemoattractant protein (MCP)-1, and decreased activities of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-px), and interleukin (IL)-4. However, AMHAE (200 mg/kg) pretreatment significantly reversed the altered pathophysiological levels of these biomolecules to near normal stages. The gastroprotective activity of AMHAE was abolished by pretreatment with l-NAME, naloxone, capsazepine, and indomethacin, demonstrating the participation of nitric oxide (NO), opioids, TRPV (vanilloid receptor-related transient receptor potential), and prostaglandins in AMHAE-assisted gastroprotection against ethanol-induced gastric injuries. This gastroprotective effect of AMHAE might be due to the downregulation of TNF-α-based NF-κB, MCP-1 signaling and strong antioxidant properties.

Enhancement of astaxanthin production using Haematococcus pluvialis with novel LED wavelength shift strategy.

Haematococcus pluvialis is a green microalga of particular interest, since it is considered the best potential natural source of astaxanthin, which is widely used as an additive for natural pigmentation. In addition, astaxanthin has recently garnered commercial interest as a nutraceutical, cosmetic, and pharmaceutical. However, producing astaxanthin from H. pluvialis necessitates separation with distinctive culture conditions, dividing between the microalgae growth and the astaxanthin production stages. Light-emitting diodes (LEDs) have emerged as a replacement for traditional light sources, and LED applications are now rapidly expanding to multiple areas in fields such as biotechnology. However, further detail application into microalgae biotechnology remains limited. In this study, we have attempted to establish new protocols based on the specific wavelength of LEDs for the cultivation and production of astaxanthin using H. pluvialis. Specifically, we applied red LEDs for microalgae cell growth and then switched to blue LEDs to induce astaxanthin biosynthesis. The result showed that astaxanthin productions based on a wavelength shift from red to blue were significantly increased, compared to those with continuous illumination using red LEDs. Furthermore, additional increase of astaxanthin production was achieved with simultaneous application of exogenous carbon with blue LED illumination. Our approach based on the proper manipulation of LED wavelengths upon H. pluvialis cell stages will enable the improvement of biomass and enhance astaxanthin production using H. pluvialis.

Immunoproteomic identification of immunodominant antigens independent of the time of infection in Brucella abortus 2308-challenged cattle.

Brucellosis is a vital zoonotic disease caused by Brucella, which infects a wide range of animals and humans. Accurate diagnosis and reliable vaccination can control brucellosis in domestic animals. This study examined novel immunogenic proteins that can be used to detect Brucella abortus infection or as an effective subcellular vaccine. In an immunoproteomic assay, 55 immunodominant proteins from B. abortus 544 were observed using two dimensional electrophoresis (2DE) and immunoblot profiles with antisera from B. abortus-infected cattle at the early (week 3), middle (week 7), and late (week 10) periods, after excluding protein spots reacting with antisera from Yersinia enterocolitica O:9-infected and non-infected cattle. Twenty-three selected immunodominant proteins whose spots were observed at all three infection periods were identified using MALDI-MS/MS. Most of these proteins identified by immunoblot and mass spectrometry were determined by their subcellular localization and predicted function. We suggest that the detection of prominent immunogenic proteins during the infection period can support the development of advanced diagnostic methods with high specificity and accuracy; subsidiarily, these proteins can provide supporting data to aid in developing novel vaccine candidates.

Interplay between clathrin and Rab5 controls the early phagocytic trafficking and intracellular survival of Brucella abortus within HeLa cells.

Lipid raft-associated clathrin is essential for host-pathogen interactions during infection. Brucella abortus is an intracellular pathogen that circumvents host defenses, but little is known about the precise infection mechanisms that involve interaction with lipid raft-associated mediators. The aim of this study was to elucidate the clathrin-mediated phagocytic mechanisms of B. abortus. The clathrin dependence of B. abortus infection in HeLa cells was investigated using an infection assay and immunofluorescence microscopy. The redistribution of clathrin in the membrane and in phagosomes was investigated using sucrose gradient fractionation of lipid rafts and the isolation of B. abortus-containing vacuoles, respectively. Clathrin and dynamin were concentrated into lipid rafts during B. abortus infection, and the entry and intracellular survival of B. abortus within HeLa cells were abrogated by clathrin inhibition. Clathrin disruption decreased actin polymerization and the colocalization of B. abortus-containing vacuoles with clathrin and Rab5 but not lysosome-associated membrane protein 1 (LAMP-1). Thus, our data demonstrate that clathrin plays a fundamental role in the entry and intracellular survival of B. abortus via interaction with lipid rafts and actin rearrangement. This process facilitates the early intracellular trafficking of B. abortus to safe replicative vacuoles.

Seroprevalence of Encephalitozoon cuniculi in pet rabbits in Korea.

Encephalitozoon cuniculi is a microsporidian parasite commonly found in rabbits that can infect humans, causing encephalitozoonosis. The prevalence of encephalitozoonosis is not well documented, even when many clinics suspect pet rabbits as being highly infected. This study investigated the seropositivity of E. cuniculi using ELISA. The examination of 186 rabbits using ELISA showed that 22.6% (42/186) were seropositive against E. cuniculi. In analysis with healthy status, all 42 seropositive sera were collected from clinically normal rabbits. Moreover, the gender and age of pet rabbits did not have anysignificant effect on E. cuniculi infection. To the best of our knowledge, this is the first report to describe the seroprevalence of E. cuniculi in pet rabbits and suggests that pet rabbits could act as an important reservoir of encephalitozoonosis for both pet animals and humans in Korea.

Study on the characteristics of increased mechanical stiffness according to changes in LCP shape to reinforce clavicle fractures.

The clavicle has various anatomic shapes unique to each individual. Additionally, with the increase in high-energy traumas such as sports injuries and traffic accidents, the patterns of fractures become complex and complicated. Thus, there is a need for a variety of shapes of locking compression plates (LCP) to accommodate different types of fractures and facilitate quicker rehabilitation. The aim of this study is to present different types of LCP that secure fracture fragments and distribute stress evenly, in comparison to typical anatomical LCPs, for reinforcing clavicle fractures. Three models were compared in this study: the typical shape, the center hole removed shape, and the double-curved wing shape. The DICOM (Digital Imaging and Communications in Medicine) file obtained from the computed tomography scan of the patient's clavicle was used to extract the three-dimensional (3D) clavicle structure. Finite element analysis (FEA) simulation was employed to analyze the structural changes of the LCP under external forces. A reinforced jig was used to apply the same type of external force to each LCP, and an experiment was conducted to analyze the mechanical impact of the LCP's structural characteristics. When comparing the stress values at the fracture zone point, resulting from the FEA simulation with applied bending forces, it was calculated that the stress dispersion effect was approximately ten times greater when transitioning from a typical LCP shape to a double-curved partial wing structure. Moreover, the ultimate stress increased 3.33 times, from 241.322 to 804.057 N, as the LCP design changed under cantilever bending conditions. This double-curved wing LCP design reduces stress concentration at the fracture site and minimizes stress in the fracture area when subjected to cantilever bending forces. Consequently, this newly designed LCP has the potential to decrease complications related to the plate and accelerate rehabilitation protocols.

Toll-like receptor 4-linked Janus kinase 2 signaling contributes to internalization of Brucella abortus by macrophages.

Brucella abortus is an intracellular pathogen that uses a crafty strategy to invade and proliferate within host cells, but the distinct signaling pathways associated with phagocytic mechanisms of B. abortus remain unclear. The present study was performed to test the hypothesis that Toll-like receptor 4 (TLR4)-linked signaling interacting with Janus kinase 2 (JAK2) plays an essential role in B. abortus phagocytosis by macrophages. The effects of TLR4-JAK2 signaling on B. abortus phagocytosis in murine macrophage RAW 264.7 cells were observed through an infection assay and confocal microscopy. We determined that the uptake of B. abortus was negatively affected by the dysfunction of TLR4 and JAK2. F-actin polymerization detected by flow cytometry and F-actin assay was amplified for B. abortus entry, whereas that event was attenuated by the disruption of TLR4 and JAK2. Importantly, JAK2 phosphorylation and actin skeleton reorganization were suppressed immediately after B. abortus infection in bone marrow-derived macrophages (BMDMs) from TLR4(-/-) mice, showing the cooperation of JAK2 with TLR4. Furthermore, small GTPase Cdc42 participated in the intermediate pathway of TLR4-JAK2 signaling on B. abortus phagocytosis. Consequently, TLR4-associated JAK2 activation in the early cellular signaling events plays a pivotal role in B. abortus-induced phagocytic processes in macrophages, implying the pathogenic significance of JAK2-mediated entry. Here, we elucidate that this specific phagocytic mechanism of B. abortus might provide achievable strategies for inhibiting B. abortus invasion.

The role of a Brucella abortus lipoprotein in intracellular replication and pathogenicity in experimentally infected mice.

Brucella abortus, the causative agent of brucellosis, can survive and replicate within host cells. Understanding bacterial virulence factors and bacteria-host cell interactions is critical for controlling brucellosis. However, little is known regarding the pathogenic mechanisms of brucellosis. A lipoprotein mutant (Gene Bank ID: 3339351) of B. abortus showed a lower rate of intracellular replication than did the wild-type strain in HeLa cells and RAW 264.7 macrophages. The adherent activity of the lipoprotein mutant was slightly increased compared to that of the wild-type strain in HeLa cells. After infection into macrophages, the lipoprotein mutant co-localized with either late endosomes or lysosomes. In mice infected with the lipoprotein mutant, fewer lipoprotein mutants were recovered from the spleen at 8 weeks post-infection compared to the wild-type strain. The ability to protect the lipoprotein mutant against infection by the virulent B. abortus strain 544 was similar to that of strain RB51. Our results indicate that the B. abortus lipoprotein is an important factor for survival within phagocytes and mice, and the B. abortus lipoprotein mutant may help improve live vaccines used to control brucellosis.

RGS2-mediated intracellular Ca2+ level plays a key role in the intracellular replication of Brucella abortus within phagocytes.

BACKGROUND: Brucella abortus can proliferate within professional and nonprofessional phagocytic host cells and thereby successfully bypass the bacteriocidal effects of phagocytes. However, the intracellular survival mechanism and factors of virulence are not fully understood. METHODS: We have investigated the role of the regulator of G protein signaling 2 (RGS2), an intracellular calcium ([Ca(2+)](i)) regulator of the host cell, in the intracellular survival of B. abortus within phagocytes. RESULTS: B. abortus infection markedly induced RGS2 messenger RNA expression in early phase and increased the [Ca(2+)](i) level up to 24 hours postinfection within macrophages from wild-type mice. The [Ca(2+)](i) level, however, was not influenced by B. abortus infection within macrophages from RGS2-deficient mice. Furthermore, B. abortus survival was reduced within RGS2-deficient macrophages, and hence bacterial proliferation was inhibited in RGS2-deficient mice. Moreover, treatment with the Ca(2+) chelator ethylenediaminetetraacetic acid (EDTA) or 1,2-bis-(2-amino-phenoxy)ethane-N,N,N',N'-tetraacetic acid acetoxymethyl ester (BAPTA-AM) and the L-type Ca(2+) channel-blocking agent nifedipine or genistein also showed a reduced intracellular replication of B. abortus within macrophages. CONCLUSION: These results indicate that B. abortus infection induces host RGS2 expression and that up-regulation of [Ca(2+)](i) levels is an essential factor for the intracellular survival of B. abortus within phagocytes.

Symbiotic relationship between filamentous algae (Halomicronema sp.) and extracellular polymeric substance-producing algae (Chlamydomonas sp.) through biomimetic simulation of natural algal mats.

To lower the cost of biomass harvesting, the growth of natural biofilm is considered to be an optimal alternative to microalgae aggregation. This study investigated algal mats that naturally agglomerate into a lump and float on water surfaces. Halomicronema sp., a filamentous cyanobacterium with high cell aggregation and adhesion to substrates, and Chlamydomonas sp., which grows rapidly and produces high extracellular polymeric substances (EPS) in certain environments, are the main microalgae that make up selected mats through next-generation sequencing analysis. These two species play a major role in the formation of solid mats, and showed a symbiotic relationship as the medium and nutritional source, particularly owing to the large amount of EPS formed by the reaction between EPS and calcium ions through zeta potential and Fourier-transform infrared spectroscopy analysis. This led to the formation of an ecological biomimetic algal mat (BAM) that mimics the natural algal mat system, and this is a way to reduce costs in the biomass production process as there is no separate treatment process for harvesting.

Hexane fraction of Prunus japonica thunb. Seed extract enhances boar sperm motility via CatSper ion channel.

Introduction: Mammalian sperm motility is facilitated by flagellar beating, which depends on active ion movement through ion channels and their regulation. Prunus japonica Thunb., also known as oriental bush cherry, is a widely used traditional medicinal plant. However, its significance in improving fertility and sperm quality has not been fully elucidated yet. One of our previous reports revealed that P. japonica seed extract (PJE) can improve human sperm motility through intracellular pH modulation. Aim of the study: The present study was designed to investigate the effects of PJE on boar spermatozoa and potential underlying mechanisms. Materials and methods: Sperm motility changes were examined using a computer-assisted sperm analysis (CASA) system under both capacitated and non-capacitated conditions. Intracellular calcium concentration was measured using either confocal microscopy or a fluorescent microplate reader with Fluo-4AM calcium fluorescent dye. Sperm capacitation-related proteins were analyzed using western blotting. Results: A significant increase in rapid motility, velocity, and linear displacement of sperm was observed in PJE-treated capacitated boar sperm, whereas the effect was insignificant in the non-capacitated counterparts. Intracellular calcium levels were significantly elevated upon PJE treatment (20-100 µg/L) in a concentration-dependent manner. The increase in intracellular calcium levels was inhibited when the sperm were treated with a CatSper (cation channel of sperm) channel inhibitor, 10 µM Mibefradil, indicating the involvement of the ion channel in the PJE modulatory mechanism. In addition, western blotting revealed an increased level of protein phosphorylation (p-tyrosine and p-PKA), which is a hallmark of sperm capacitation. Conclusions: PJE treatment resulted in a combination of increased motility, intracellular calcium concentration, and capacitation, thereby indicating its potential to ameliorate sperm motility parameters and induce capacitation of boar spermatozoa as a result of intracellular calcium elevation via the CatSper channel. Our observations further elaborate ion channel-related underlying mechanisms and show putative implications of the seed extract of traditionally used P. japonica Thunb. in ameliorating sperm quality.

Exploring Physical Lumbar Microvascular Geometry Through Endoscopy and Illustrations: Implications for Clinical Interpretation.

STUDY DESIGN: Retrospective Study. OBJECTIVES: Minimally invasive endoscopic spinal surgery is gaining popularity, but our understanding of the lumbar spine's microvascular geometry relies heavily on cadaver studies and textbook illustrations. Additionally, inconsistent nomenclature of vessels in the literature hampers effective communication among surgeons. This study aims to improve the clarity and comprehensibility of the lumbar spinal microvascular geometry under endoscopic view. METHODS: The study included 400 patients who underwent endoscopic spinal surgery for lumbar spinal canal stenosis and foraminal stenosis. The surgeries were performed by an experienced surgeon using either the interlaminar or transforaminal approach. Endoscopic video recordings were further analyzed to map the microvascular geometry and common bleeding foci. The observed results were cross-referenced with existing literature to reconstruct a comprehensive view of the vascular anatomy. RESULTS: The transforaminal approach commonly encounters bleeding foci originating from the major branches of the segmental lumbar artery and the emissary veins within the foramen. The interlaminar approach primarily encounters bleeding foci from the muscle vessels in the dorsal lamina, which are believed to be located near the ends of the three main branches. In the intracanal region, epidural vessels form a rotary loop above the disc, which can contribute to most of the bleeding during discectomy. CONCLUSIONS: This study provides a comprehensive understanding of the microvascular anatomy in the lumbar spine during endoscopic spinal surgery. Recognizing the geometry will help surgeons anticipate and control bleeding, reducing the risk of complications. The findings contribute to the improvement of surgical techniques and patient safety in endoscopic spinal surgery.

Anticoccidial effect of supplemental dietary Galla Rhois against infection with Eimeria tenella in chickens.

The anticoccidial effects of Galla Rhois (GR) powder, which contains a major tannin-derived component of 52.7%, were evaluated in chickens following oral infection with Eimeria tenella. One-day-old chickens were assigned to five groups (control, unsupplemented, GR 0.5% supplemented [GRS 0.5%], GRS 1.0% [GRS 1.0%] and salinomycin supplemented [SS]). The chickens were fed a standard diet supplemented or not supplemented with GR or salinomycin for 10 days prior to infection. The birds received the supplemented diets continuously until 10 days post infection. The effects of GR on a E. tenella infection were evaluated by several parameters, including body weight gain, feed intake, oocyst excretion, bloody diarrhoea, and lesion scores. Infected chickens on the GRS and SS diets had a relatively moderate body weight loss (reduction ratio < 15%) and improved feed conversion. GRS and SS chickens produced significantly fewer faecal oocysts (P<0.05) and showed milder bloody diarrhoea compared with the E. tenella-infected control group. Furthermore, the lesion scores of both the GRS 0.5% and GRS 1.0% groups were significantly lower than the scores of the unsupplemented group on day 5 post infection. The lesion scores for the GR groups were similar to the scores for the SS group. In conclusion, this study suggests that GR appears to be as efficacious as salinomycin against E. tenella infection. GR supplementation leads to a reduction in infected chickens, although infected chickens are still affected compared with the uninfected control group. GR-based diets may be beneficial in preventing or treating coccidial infections in poultry.

The difference of surgical site infection according to the methods of lumbar fusion surgery.

STUDY DESIGN: Retrospective analysis. OBJECTIVE: To compare the rates and types of a surgical site infection according to the surgical options in spine surgeries. SUMMARY OF BACKGROUND DATA: Scant literatures exist on the difference of surgical site infection according to the surgical methods. We presumed that the incidence of infection after posterior lumbar interbody fusion (PLIF) was higher than posterior or posterolateral fusion (PF, PLF) due to several reasons. METHODS: A retrospective analysis was made on the patients who received instrumented spinal fusion surgeries from 2000 to 2009. The differences of surgical site infection rates and characteristics were compared between the patients who received PF or PLF (group I) and PLIF (group II). In addition, the infection rate according to the graft options and number of cages was compared in group II. RESULTS: A significant difference (P = 0.003) of infection rate between group I (0.3%, 3 cases out of 974) and group II (1.37%, 29 cases out of 2110) was observed. In group I, 67% of infections were wound infections and 33% were osteomyelitis. In group II, 23% were wound infections, 73% were osteomyelitis, and 4% were osteomyelitis combined with wound infection. Significant increase of infection rate was observed in the single cage group (P = 0.001) and mainly local bone grafted group (P = 0.030). CONCLUSIONS: The infection rate of PLIF was higher than that of PF or PLF. Considering the increased infection rate in local bone grafted group and 52% of the infection cases after interbody fusion was osteomyelitis around interbody space, contaminated local bones and interbody space were suspected as major routes of contamination. The higher infection rate in single cage group than that of double cage group was attributed to vulnerability of remained avascular disk materials to infection.

Unstable fracture of fusion mass in old healed tuberculous kyphosis: Case report.

INTRODUCTION AND IMPORTANCE: Old healed spinal tuberculosis sometimes makes bony ankylosis with kyphotic deformity. This bony ankylosis with adjacent vertebra is like ankylosing spinal disorders (ASDs) such as ankylosing spondylitis and diffuse idiopathic skeletal hyperostosis. There is lots of report which revealed that conservative management might be failed in thoracolumbar fracture in ASDs. However, there is no report which shows surgical treatment was finally done because conservative management was failed in fracture healing of fusion mass caused by old spinal tuberculosis. CASE PRESENTATION: A 68 year-old male patient has suffered from spinal tuberculosis about fifty years ago and then has bony kyphotic ankylosis. He fell off a ladder and was conducted conservative treatment under diagnosis of a sprain at a doctor's office. He was diagnosed with fracture of fusion mass after computed tomography and magnetic resonance image scans in our hospital due to persistent back pain. At first, he refused operation strongly, but underwent eventually posterior fixation without anterior support and angle correction for persistent pain and fracture nonunion. We finally achieved bone union after postoperative nine months. CLINICAL DISCUSSION: The characteristics of old healed spinal tuberculosis with kyphotic deformity is similar to that of ASDs. The spine fractures among the patients with ASDs can be easily missed. So, Checking whole spine CT or MRI is recommended for fracture screening to ASD patients with back or neck pain after trauma. For unstable AOSpine type B- or C-type injuries, conservative management is not recommended. This recommendations should also apply to patients with spinal tuberculosis. CONCLUSION: In patients with bony kyphotic ankylosis due to spinal tuberculosis, minor trauma can cause unstable fracture. If there's found unstable fracture, surgery should be underwent as soon as possible for preventing neurologic deficits. Hence, we would like to report this case with literature reviews.

Numerical simulation and biomechanical analysis of locking screw caps on clavicle locking plates.

BACKGROUND: The risk of displaced and comminuted midshaft clavicle fractures is increased in high-energy traumas such as sport injuries and traffic accidents. Open reduction and plate fixation have been widely used for midshaft clavicle fractures. Among various plates for clavicle shaft fractures, superior locking compression plates (LCPs) have been mostly used. In plate fixation, nonunion caused by implant failure is the most difficult complication. The most common reasons for metal plate failure are excessive stress and stress concentration caused by cantilever bending. These causes were easily addressed using a locking screw cap (LSC). METHODS: The clavicle 3-dimensional image was made from a computed tomography scan, and the clavicle midshaft fracture model was generated with a 10-mm interval. The fracture model was fixed with a superior LCP, and finite element analysis was conducted between the presence (with LSC model) and absence (without LSC model) of an LSC on the site of the fracture. The stresses of screw holes in models with and without LSCs were measured under 3 forces: 100 N cantilever bending force, 100 N axial compression force, and 1 N·m axial torsion force. After the finite element analysis, a validation test was conducted on the cantilever bending force known as the greatest force applied to superior locking plates. RESULTS: The mean greatest stress under the cantilever bending force was significantly greater than other loading forces. The highest stress site was the screw hole edge on the fracture site in both models under the cantilever bending and axial compression forces. Under the axial torsional force, the maximum stress point was the lateral first screw hole edge. The ultimate plate stress of the with LSC model is completely lower than that of the without LSC model. According to the validation test, the stiffness, ultimate load, and yield load of the with LSC model were higher than those of the without LSC model. CONCLUSIONS: Therefore, inserting an LSC into an empty screw hole in the fracture area reduces the maximum stress on an LCP and improves biomechanical stability.