Yet Another Tutorial of Disturbance Observer: Robust Stabilization and Recovery of Nominal Performance

This paper presents a tutorial-style review on the recent results about the disturbance observer (DOB) in view of robust stabilization and recovery of the nominal performance. The analysis is based on the case when the bandwidth of Q-filter is large, and it is explained in a pedagogical manner that, even in the presence of plant uncertainties and disturbances, the behavior of real uncertain plant can be made almost similar to that of disturbance-free nominal system both in the transient and in the steady-state. The conventional DOB is interpreted in a new perspective, and its restrictions and extensions are discussed

More Proofs for `Determination of Stability with respect to Positive Orthant for a Class of Positive Nonlinear Systems'

This is a supplement material for a published article by the authors.In the published paper `Determination of Stability with respect to Positive Orthant for a Class of Positive Nonlinear Systems,' IEEE Trans. on Automatic Control, vol. 53, no. 5, pp. 1329-1334, 2008, by the authors, some proofs are omitted due to the space limitation of the journal. In this note, we present those omitted proofs

Addendum for "A Study of Disturbance Observers with Unknown Relative Degree"

[Preprint] The paper "A Study of Disturbance Observers with Unknown Relative Degree" [1] by the authors could not include the proofs for Theorem 5 and Theorem 6 due to the page limit. We provide them in this supplementary document, and an example is included with simulation results

Height Restoration after Balloon Kyphoplasty in Rheumatoid Patients with Osteoporotic Vertebral Compression Fracture

Study DesignRetrospective study.PurposeThis study was conducted to compare vertebral body height restoration rate in rheumatoid arthritis (RA) patients who had undergone percutaneous balloon kyphoplasty (KP) with that of control group who had matched age, sex, body mass index, and bone mineral density.Overview of LiteratureThere is no report on result of KP in RA patients.MethodsPostoperative height restoration rate of RA group consisting of 15 patients (18 vertebral bodies) who had undergone KP due to osteoporotic vertebral compression fracture with a 30% or higher vertebral compression rate between May 2005 and January 2013 were compared to control group consisting of 38 patients (39 vertebral bodies) who had matched age, sex, body mass index, and bone mineral density.ResultsNo statically significant difference in age (p=0.846), sex (p=0.366), body mass index (p=0.826), bone mineral density (p=0.349), time to surgery (p=0.528), polymethylmethacrylate injection time (p=0.298), or amount (p=0.830) was found between the RA group and the control group. However, preoperative compression rate in the RA group was significantly (p=0.025) higher compared to that in the control group. In addition, postoperative height restoration rate showed significant correlation with the RA group (p=0.008). Although higher incidence of recollapse occurred in the RA group compared to that in the control group, the difference was not statistically significant (p=0.305).ConclusionsCompared to the control group, RA patients showed higher compression rate and higher vertebral restoration rate after KP, indirectly indicating weaker bone quality in patients with RA. Higher incidence of recollapse occurred in the RA group compared to that in the control group, although it was not statistically significant

Comparison of total body irradiation-based or non-total body irradiation-based conditioning regimens for allogeneic stem cell transplantation in pediatric leukemia patients

Purpose : This study aims to compare the outcome of total body irradiation (TBI)- or non-TBI-containing conditioning regimens for leukemia in children. Methods : We retrospectively evaluated 77 children conditioned with TBI (n=40) or non-TBI (n=37) regimens, transplanted at Chonnam National University Hospital between January 1996 and December 2007. The type of transplantation, disease status at the time of transplant, conditioning regimen, engraftment kinetics, development of graft-versus-host disease (GVHD), complications, cause of deaths, overall survival (OS), and event-free survival (EFS) were compared between the 2 groups. Results : Among 34 patients with acute lymphoblastic leukemia (ALL), 28 (82.4%) were in the TBI group, while 72.7% (24/33) of patients with myeloid leukemia were in the non-TBI group. Although the 5-year EFS of the 2 groups was similar for all patients (62% vs 63%), the TBI group showed a better 5-year EFS than the non-TBI group when only ALL patients were analyzed (65% vs 17%&#59; P =0.005). In acute myelogenous leukemia patients, the non-TBI group had better survival tendency (73% vs 38%&#59; P=0.089). The incidence of GVHD, engraftment, survival, cause of death, and late complications was not different between the 2 groups. Conclusion : The TBI and non-TBI groups showed comparable results, but the TBI group showed a significantly higher 5-year EFS than the non-TBI group in ALL patients. Further prospective, randomized controlled studies involving larger number of patients are needed to assess the late-onset complications and to compare the socioeconomic quality of life

Outcomes of Revision Surgery Following Instrumented Posterolateral Fusion in Degenerative Lumbar Spinal Stenosis: A Comparative Analysis between Pseudarthrosis and Adjacent Segment Disease

Study DesignRetrospective study.PurposeWe examined the clinical and radiological outcomes of patients who received revision surgery for pseudarthrosis or adjacent segment disease (ASD) following decompression and instrumented posterolateral fusion (PLF).Overview of LiteratureAt present, information regarding the outcomes of revision surgery for complications such as pseudarthrosis and ASD following instrumented PLF is limited.MethodsThis study examined 60 patients who received PLF for degenerative lumbar spinal stenosis and subsequently developed pseudarthrosis or ASD leading to revision surgery. Subjects were divided into a group of 21 patients who received revision surgery for pseudarthrosis (Group P) and a group of 39 patients who received revision surgery for ASD (Group A). Clinical outcomes were evaluated using the visual analogue scales for back pain (VAS-BP) and leg pain (VAS-LP), the Korean Oswestry disability index (K-ODI), and each patient's subjective satisfaction. Radiological outcomes were evaluated from the extent of bone union, and complications in the two groups were compared.ResultsVAS-LP at final follow-up was not statistically different between the two groups (p =0.353), although VAS-BP and K-ODI at final follow-up were significantly worse in Group P than in Group A (all p <0.05), and only 52% of the patients in Group P felt that their overall well-being had improved following revision surgery. Fusion rates after the first revision surgery were 71% (15/21) in Group P and 95% (37/39) in Group A (p =0.018). The rate of reoperation was significantly higher in Group P (29%) than in Group A (5%) (p =0.021) due to complications.ConclusionsClinical and radiological outcomes were worse in patients who had received revision surgery for pseudarthrosis than in those who had revision surgery for ASD. Elderly patients should be carefully advised of the risks and benefits before planning revision surgery for pseudarthrosis

Mitochondria-targeted antioxidant MitoQ ameliorates experimental mouse colitis by suppressing NLRP3 inflammasome-mediated inflammatory cytokines

BACKGROUND: MitoQ is a mitochondria-targeted derivative of the antioxidant ubiquinone, with antioxidant and anti-apoptotic functions. Reactive oxygen species are involved in many inflammatory diseases including inflammatory bowel disease. In this study, we assessed the therapeutic effects of MitoQ in a mouse model of experimental colitis and investigated the possible mechanisms underlying its effects on intestinal inflammation. METHODS: Reactive oxygen species levels and mitochondrial function were measured in blood mononuclear cells of patients with inflammatory bowel disease. The effects of MitoQ were evaluated in a dextran sulfate sodium-induced colitis mouse model. Clinical and pathological markers of disease severity and oxidative injury, and levels of inflammatory cytokines in mouse colonic tissue were measured. The effect of MitoQ on inflammatory cytokines released in the human macrophage-like cell line THP-1 was also analyzed. RESULTS: Cellular and mitochondrial reactive oxygen species levels in mononuclear cells were significantly higher in patients with inflammatory bowel disease (P <0.003, cellular reactive oxygen species; P <0.001, mitochondrial reactive oxygen species). MitoQ significantly ameliorated colitis in the dextran sulfate sodium-induced mouse model in vivo, reduced the increased oxidative stress response (malondialdehyde and 3-nitrotyrosine formation), and suppressed mitochondrial and histopathological injury by decreasing levels of inflammatory cytokines IL-1 beta and IL-18 (P <0.001 and P <0.01 respectively). By decreasing mitochondrial reactive oxygen species, MitoQ also suppressed activation of the NLRP3 inflammasome that was responsible for maturation of IL-1 beta and IL-18. In vitro studies demonstrated that MitoQ decreases IL-1 beta and IL-18 production in human THP-1 cells. CONCLUSION: Taken together, our results suggest that MitoQ may have potential as a novel therapeutic agent for the treatment of acute phases of inflammatory bowel disease

Genome-wide association study to identify novel loci and genes for Fusarium root rot resistance in sweet potato using genotyping-by-sequencing

Fusarium root rot, caused by Fusarium solani, is a major post-harvest disease in sweet potatoes (Ipomoea batatas (L.) Lam.). An effective strategy for controlling this disease is the development of resistant varieties. In this study, a genome-wide association study (GWAS) was conducted on 96 sweet potato genotypes to identify novel candidate loci and dissect the genetic basis of Fusarium root rot resistance. Genotyping was performed using genotyping-by-sequencing (GBS), and 44,255 SNPs were identified after filtering. The genotypes (n = 96) were evaluated through resistance tests in 2021 and 2022, separately and combined. The GWAS identified two significant SNP markers (LG3_22903756 and LG4_2449919) on chromosomes 3 and 4 associated with Fusarium root rot resistance, respectively. Lesion length showed significant differences between homozygous A and G alleles of LG3_22903756, which can potentially be used to develop molecular markers for selecting accessions resistant to Fusarium root rot. Expression analysis of 11 putative genes flanking the significant SNPs revealed the alteration in the expression of nine genes, indicating their possible involvement in Fusarium root rot resistance. The results of this study will aid in the marker-assisted selection and functional analysis of candidate genes for Fusarium root rot resistance in sweet potatoes

Identification of MYC as an antinecroptotic protein that stifles RIPK1-RIPK3 complex formation

The underlying mechanism of necroptosis in relation to cancer is still unclear. Here, MYC, a potent oncogene, is an antinecroptotic factor that directly suppresses the formation of the RIPK1-RIPK3 complex. Gene set enrichment analyses reveal that the MYC pathway is the most prominently down-regulated signaling pathway during necroptosis. Depletion or deletion of MYC promotes the RIPK1-RIPK3 interaction, thereby stabilizing the RIPK1 and RIPK3 proteins and facilitating necroptosis. Interestingly, MYC binds to RIPK3 in the cytoplasm and inhibits the interaction between RIPK1 and RIPK3 in vitro. Furthermore, MYC-nick, a truncated form that is mainly localized in the cytoplasm, prevented TNF-induced necroptosis. Finally, down-regulation of MYC enhances necroptosis in leukemia cells and suppresses tumor growth in a xenograft model upon treatment with birinapant and emricasan. MYC-mediated suppression of necroptosis is a mechanism of necroptosis resistance in cancer, and approaches targeting MYC to induce necroptosis represent an attractive therapeutic strategy for cancer

Selective embolization of the internal iliac arteries for the treatment of intractable hemorrhage in children with malignancies

PurposeAcute internal hemorrhage is an occasionally life-threatening complication in pediatric cancer patients. Many therapeutic approaches have been used to control bleeding with various degrees of success. In this study, we evaluated the efficacy of selective internal iliac artery embolization for controlling acute intractable bleeding in children with malignancies.MethodsWe retrospectively evaluated the cases of 6 children with various malignancies (acute lymphoblastic leukemia, acute myelogenous leukemia, chronic myelogenous leukemia, T-cell prolymphocytic leukemia, Langerhans cell histiocytosis, and rhabdomyosarcoma), who had undergone selective arterial embolization (SAE) of the internal iliac artery at the Chonnam National University Hwasun Hospital between January 2004 and December 2009. SAE was performed by an interventional radiologist using Gelfoam® and/or Tornado® coils.ResultsThe patients were 5 boys and 1 girl with median age of 6.9 years (range, 0.7-14.8 years) at the time of SAE. SAE was performed once in 4 patients and twice in 2, and the procedure was unilateral in 2 and bilateral in 4. The causes of hemorrhage were as follows: hemorrhagic cystitis (HC) in 3 patients, procedure-related internal iliac artery injuries in 2 patients, and tumor rupture in 1 patient. Initial attempt at conservative management was unsuccessful. Of the 6 patients, 5 (83.3%) showed improvement after SAE without complications.ConclusionSAE may be a safe and effective procedure for controlling acute intractable hemorrhage in pediatric malignancy patients. This procedure may obviate the need for surgery, which carries an attendant risk of morbidity and mortality in cancer patients with critical conditions