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2.
Ann Pediatr Endocrinol Metab ; 28(4): 312-317, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38173385

RESUMO

Hypophosphatasia (HPP) is a rare condition characterized by abnormal bone mineralization. The manifestations of HPP vary from no symptoms to intrauterine fetal death; short stature is another indication of HPP. A 3 ½-year-old boy presented with short stature, transient hypercalcemia, and mild gait disturbance without definite bony deformity. Laboratory examination revealed transient hypercalcemia, normal phosphorous and 25-hydroxy vitamin D levels, and mildly low alkaline phosphatase levels. A targeted next-generation sequencing panel associated with inborn errors of metabolism revealed a pathogenic heterozygous mutation in the ALPL gene, c.979T>C (p.Phe327Leu). When a child visits a hospital with short stature, decreased height velocity, and low alkaline phosphatase level, clinicians should consider the possibility of HPP even if definite skeletal dysplasia is not evident.

3.
Nanomaterials (Basel) ; 14(1)2023 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-38202464

RESUMO

Layered honeycomb magnets with strong atomic spin-orbit coupling at transition metal sites have been intensively studied for the search of Kitaev magnetism and the resulting non-Abelian braiding statistics. α-RuCl3 has been the most promising candidate, and there have been several reports on the realization of sibling compounds α-RuBr3 and α-RuI3 with the same crystal structure. Here, we investigate correlated electronic structures of α-RuCl3 and α-RuI3 by employing first-principles dynamical mean-field theory. Our result provides a valuable insight into the discrepancy between experimental and theoretical reports on transport properties of α-RuI3, and suggests a potential realization of correlated flat bands with strong spin-orbit coupling and a quantum spin-Hall insulating phase in α-RuI3.

5.
Korean J Intern Med ; 37(4): 841-850, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35811370

RESUMO

BACKGROUND/AIMS: We evaluated the feasibility and long-term efficacy of the combination of cytarabine, idarubicin, and all-trans retinoic acid (ATRA) for treating patients with newly diagnosed acute promyelocytic leukemia (APL). METHODS: We included 87 patients with newly diagnosed acute myeloid leukemia and a t(15;17) or promyelocytic leukemia/retinoic acid receptor alpha (PML-RARα) mutation. Patients received 12 mg/m2/day idarubicin intravenously for 3 days and 100 mg/m2/day cytarabine for 7 days, plus 45 mg/m2/day ATRA. Clinical outcomes included complete remission (CR), relapse-free survival (RFS), overall survival (OS), and the secondary malignancy incidence during a 20-year follow-up. RESULTS: The CR, 10-year RFS, and 10-year OS rates were 89.7%, 94.1%, and 73.8%, respectively, for all patients. The 10-year OS rate was 100% for patients that achieved CR. Subjects were classified according to the white blood cell (WBC) count in peripheral blood at diagnosis (low-risk, WBC < 10,000/mm3; high-risk, WBC ≥ 10,000/mm3). The low-risk group had significantly higher RFS and OS rates than the high-risk group, but the outcomes were not superior to the current standard treatment (arsenic trioxide plus ATRA). Toxicities were similar to those observed with anthracycline plus ATRA, and higher than those observed with arsenic trioxide plus ATRA. The secondary malignancy incidence after APL treatment was 2.7%, among the 75 patients that achieved CR, and 5.0% among the 40 patients that survived more than 5 years after the APL diagnosis. CONCLUSION: Adding cytarabine to anthracycline plus ATRA was not inferior to anthracycline plus ATRA alone, but it was not comparable to arsenic trioxide plus ATRA. The probability of secondary malignancy was low.


Assuntos
Leucemia Promielocítica Aguda , Antraciclinas/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Trióxido de Arsênio/efeitos adversos , Citarabina/efeitos adversos , Seguimentos , Humanos , Idarubicina/efeitos adversos , Leucemia Promielocítica Aguda/diagnóstico , Leucemia Promielocítica Aguda/tratamento farmacológico , Leucemia Promielocítica Aguda/genética , Recidiva , Indução de Remissão , Resultado do Tratamento , Tretinoína/efeitos adversos
7.
J Phys Condens Matter ; 34(2)2021 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-34614480

RESUMO

The realization of Kitaev's honeycomb magnetic model in real materials has become one of the most pursued topics in condensed matter physics and materials science. If found, it is expected to host exotic quantum phases of matter and offers potential realizations of fault-tolerant quantum computations. Over the past years, much effort has been made on 4d- or 5d-heavy transition metal compounds because of their intrinsic strong spin-orbit coupling. But more recently, there have been growing shreds of evidence that the Kitaev model could also be realized in 3d-transition metal systems with much weaker spin-orbit coupling. This review intends to serve as a guide to this fast-developing field focusing on systems withd7transition metal occupation. It overviews the current theoretical and experimental progress on realizing the Kitaev model in those systems. We examine the recent experimental observations of candidate materials with Co2+ions: e.g., CoPS3, Na3Co2SbO6, and Na2Co2TeO6, followed by a brief review of theoretical backgrounds. We conclude this article by comparing experimental observations with density functional theory calculations. We stress the importance of inter-t2ghopping channels and Hund's coupling in the realization of Kitaev interactions in Co-based compounds, which has been overlooked in previous studies. This review suggests future directions in the search for Kitaev physics in 3dcobalt compounds and beyond.

8.
J Phys Condens Matter ; 34(4)2021 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-34517360

RESUMO

Finding new materials with antiferromagnetic (AFM) Kitaev interaction is an urgent issue for quantum magnetism research. We conclude that Na3Co2SbO6and Na2Co2TeO6are new honeycomb cobalt-based systems with AFM Kitaev interaction by carrying out inelastic neutron scattering experiments and subsequent analysis. The spin-orbit excitons observed at 20-28 meV in both compounds strongly support the idea that Co2+ions of both compounds have a spin-orbital entangledJeff= 1/2 state. Furthermore, we found that a generalized Kitaev-Heisenberg Hamiltonian can describe the spin-wave excitations of both compounds with additional 3rd nearest-neighbor interaction. Our best-fit parameters show significant AFM Kitaev terms and off-diagonal symmetric anisotropy terms of a similar magnitude in both compounds. We also found a strong magnon-damping effect at the higher energy part of the spin waves, entirely consistent with observations in other Kitaev magnets. Our work suggests Na3Co2SbO6and Na2Co2TeO6as rare examples of the AFM Kitaev magnets based on the systematic studies of the spin waves and analysis.

9.
Genes (Basel) ; 12(5)2021 05 06.
Artigo em Inglês | MEDLINE | ID: mdl-34066320

RESUMO

The diagnosis of inherited platelet function disorders (IPFDs) is challenging owing to the unavailability of essential testing methods, including light transmission aggregometry and flow cytometry, in several medical centers in Korea. This study, conducted by the Korean Pediatric Hematology Oncology Group from March 2017 to December 2020, aimed to identify the causative genetic variants of IPFDs in Korean patients using next-generation sequencing (NGS). Targeted exome sequencing, followed by whole-genome sequencing, was performed for diagnosing IPFDs. Of the 11 unrelated patients with suspected IPFDs enrolled in this study, 10 patients and 2 of their family members were diagnosed with Glanzmann thrombasthenia (GT). The variant c.1913+5G>T of ITGB3 was the most common, followed by c.2333A>C (p.Gln778Pro) of ITGB2B. Known variants of GT, including c.917A>C (p.His306Pro) of ITGB3 and c.2975del (p.Glu992Glyfs*), c.257T>C (p.Leu86Pro), and c.1750C>T (p.Arg584*) of ITGA2B, were identified. Four novel variants of GT, c.1451G>T (p.Gly484Val) and c.1595G>T (p.Cys532Phe) of ITGB3 and c.1184G>T (p.Gly395Val) and c.2390del (p.Gly797Valfs*29) of ITGA2B, were revealed. The remaining patient was diagnosed with platelet type bleeding disorder 18 and harbored two novel RASGRP2 variants, c.1479dup (p.Arg494Alafs*54) and c.813+1G>A. We demonstrated the successful application of NGS for the accurate and differential diagnosis of heterogeneous IPFDs.


Assuntos
Integrina alfa2/genética , Integrina beta3/genética , Polimorfismo de Nucleotídeo Único , Trombastenia/genética , Pré-Escolar , Feminino , Frequência do Gene , Humanos , Lactente , Recém-Nascido , Masculino , República da Coreia
10.
Children (Basel) ; 8(2)2021 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-33562522

RESUMO

Acute myeloid leukemia (AML) is the second most common pediatric leukemia, with a survival rate of 70%. In this retrospective study, we evaluated the treatment outcomes of pediatric AML among 144 patients diagnosed between 2000 and 2013. After induction, 80.6% of patients achieved complete remission (CR). The 5-year overall survival (OS) and event-free survival (EFS) rates were 58.8 ± 4.2% and 49.8 ± 4.2%, respectively. Based on the response to induction therapy, the 5-year OS was 66.9 ± 5.7% in patients with CR (p < 0.001). Ninety-nine patients with CR after induction therapy were examined, and their 5-year OS and EFS were 66.4 ± 4.9% and 56.3 ± 5.1%, respectively. The 5-year OS rates according to treatment were 59.9 ± 7.4% in the chemotherapy group and 72.3 ± 6.3% in the hematopoietic stem cell transplantation (HSCT) group (p = 0.089). The EFS was 50.1 ± 7.4% in the chemotherapy group and 61.7 ± 6.9% in the HSCT group (p = 0.098). OS and EFS according to cytogenetics were insignificant. Our findings confirmed that the response to induction treatment was important for survival and HSCT had no significant survival benefits compared with those of chemotherapy. Moreover, many early induction deaths under the age of 2 years were observed.

13.
Yeungnam Univ J Med ; 38(3): 208-218, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33242384

RESUMO

BACKGRUOUND: Hemophagocytic lymphohistiocytosis (HLH) is a rare but severe, life-threatening inflammatory condition if untreated. We aimed to investigate the etiologies, outcomes, and risk factors for death in children and adults with HLH. METHODS: The medical records of patients who met the HLH criteria of two regional university hospitals in Korea between January 2001 and December 2019 were retrospectively investigated. RESULTS: Sixty patients with HLH (35 children and 25 adults) were included. The median age at diagnosis was 7.0 years (range, 0.1-83 years), and the median follow-up duration was 8.5 months (range, 0-204 months). Four patients had primary HLH, 48 patients had secondary HLH (20 infection-associated, 18 neoplasm-associated, and 10 autoimmune-associated HLH), and eight patients had HLH of unknown cause. Infection was the most common cause in children (14/35, 40.0%), whereas neoplasia was the most common cause in adults (13/25, 52.0%). Twenty-eight patients were treated with HLH-2004/94 immunochemotherapy. The 5-year overall survival (OS) rate for all HLH patients was 59.9%. The 5-year OS rates for patients with primary, infection-associated, neoplasm-associated, autoimmune-associated, and unknown cause HLH were 25.0%, 85.0%, 26.7%, 87.5%, and 62.5%, respectively. Using multivariate analysis, neoplasm-induced HLH (p=0.001) and a platelet count <50×109/L (p=0.008) were identified as independent risk factors for poor prognosis in patients with HLH. CONCLUSION: Infection was the most common cause of HLH in children, while it was neoplasia in adults. The 5-year OS rate for all HLH patients was 59.9%. HLH caused by an underlying neoplasm or a low platelet count at the time of diagnosis were risk factors for poor prognosis.

14.
J Korean Med Sci ; 35(46): e393, 2020 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-33258329

RESUMO

BACKGROUND: Hodgkin's lymphoma (HL) constitutes 10%-20% of all malignant lymphomas and has a high cure rate (5-year survival, around 90%). Recently, interest has increased concerning preventing secondary complications (secondary cancer, endocrine disorders) in long-term survivors. We aimed to study the epidemiologic features and therapeutic outcomes of HL in children, adolescents, and young adults in Korea. METHODS: We performed a multicenter, retrospective study of 224 patients aged < 25 years diagnosed with HL at 22 participating institutes in Korea from January 2007 to August 2016. RESULTS: A higher percentage of males was diagnosed at a younger age. Nodular sclerosis histopathological HL subtype was most common, followed by mixed cellularity subtype. Eighty-one (36.2%), 101 (45.1%), and 42 (18.8%) patients were classified into low, intermediate, and high-risk groups, respectively. Doxorubicin, bleomycin, vinblastine, dacarbazine was the most common protocol (n = 102, 45.5%). Event-free survival rate was 86.0% ± 2.4%, while five-year overall survival (OS) rate was 96.1% ± 1.4%: 98.7% ± 1.3%, 97.7% ± 1.6%, and 86.5% ± 5.6% in the low, intermediate, and high-risk groups, respectively (P = 0.021). Five-year OS was worse in patients with B-symptoms, stage IV disease, high-risk, splenic involvement, extra-nodal lymphoma, and elevated lactate dehydrogenase level. In multivariate analysis, B-symptoms and extra-nodal involvement were prognostic factors for poor OS. Late complications of endocrine disorders and secondary malignancy were observed in 17 and 6 patients, respectively. CONCLUSION: This is the first study on the epidemiology and treatment outcomes of HL in children, adolescents, and young adults in Korea. Future prospective studies are indicated to develop therapies that minimize treatment toxicity while maximizing cure rates in children, adolescents, and young adults with HL.


Assuntos
Antineoplásicos/uso terapêutico , Doença de Hodgkin/tratamento farmacológico , Adolescente , Antineoplásicos/efeitos adversos , Bleomicina/efeitos adversos , Bleomicina/uso terapêutico , Criança , Pré-Escolar , Doxorrubicina/efeitos adversos , Doxorrubicina/uso terapêutico , Doenças do Sistema Endócrino/etiologia , Feminino , Transplante de Células-Tronco Hematopoéticas , Doença de Hodgkin/mortalidade , Doença de Hodgkin/patologia , Humanos , Lactente , Recém-Nascido , Masculino , República da Coreia , Estudos Retrospectivos , Taxa de Sobrevida , Resultado do Tratamento , Vimblastina/efeitos adversos , Vimblastina/uso terapêutico , Adulto Jovem
15.
Nanoscale ; 12(25): 13501-13506, 2020 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-32555905

RESUMO

Recent experimental findings of two dimensional ferromagnetism in Fe3GeTe2, whose critical temperature can reach room temperature by gating, has attracted great research interest. Here we performed elaborate ab initio studies using density functional theory, dynamical mean-field theory and magnetic force response theory. In contrast to the conventional wisdom, it is unambiguously shown that Fe3GeTe2 is not ferromagnetic but is antiferromagnetic, carrying zero net moment in its stoichiometric phase. Fe defect and hole doping are the keys to make this material ferromagnetic as supported by previously disregarded experiments. Furthermore, we found that electron doping also induces the antiferro- to ferro-magnetic transition. It is crucial to understand the notable recent experiments on gate-controlled ferromagnetism. Our results not only reveal the origin of ferromagnetism of this material but also show how it can be manipulated with defects and doping.

16.
Pediatr Res ; 88(5): 749-755, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32311699

RESUMO

BACKGROUND: Oral propranolol has become first-line treatment for infantile hemangiomas (IHs). This study focused on identifying cytokines related to the biology of IH and early regression indicators of IH after propranolol treatment. METHODS: For inclusion, the patients had to be aged less than 1 year and have an IH with a largest diameter ≥2 cm. Patients were scheduled to receive 1 year of propranolol treatment. Serum cytokines involved in angiogenesis, vasculogenesis, and/or chronic inflammation were analyzed at 0, 1, and/or 12 months after treatment using Multiplex Luminex assays. RESULTS: Among the 49 evaluable patients, 33 completed the 1-year treatment: 16 showed excellent response and 12 had good response to propranolol. Significant decreases in serum MMP-2, bFGF, VEGF-α, and MCP-1 levels were observed after 1 year of treatment compared to pretreatment values. The maximal diameters of the lesions significantly correlated with pretreatment serum VEGF-α, bFGF, and MMP-9. Patients with higher bFGF and VEGF levels showed better response to propranolol at 1 year. CONCLUSION: MMP-2, VEGF-α, bFGF, and MCP-1 may involve in the biology of IH and their downregulation may be associated with involution processes of IH. Pretreatment bFGF and VEGF could be novel biomarkers for predicting response to propranolol. IMPACT: We found that decreases in the concentrations of MMP-2, bFGF, VEGF, and MCP-1 were associated with regression of the hemangioma, which indicates that one of the mechanisms of propranolol in the treatment of proliferative hemangiomas may involve downregulation of those cytokines. Patients with higher bFGF and VEGF levels showed better response to propranolol at 1 year. Importantly, serum bFGF higher than 37.07 pg/mL may predict an excellent response to propranolol. Therefore, along with the patient's age and the size and visual characteristics of the lesion, bFGF levels could help determine the viability of propranolol use in the treatment of IHs. Our study represented extensive serum profiling in IH, reporting the indicators and molecules clearly related to IH regression with propranolol treatment. The authors believe that monitoring serum cytokines, including MMP-2, bFGF, VEGF, and MCP-1, in IH patients could be important, in addition to clinical follow-up, for determining when to start and end propranolol treatment.


Assuntos
Antagonistas Adrenérgicos beta/administração & dosagem , Antineoplásicos/administração & dosagem , Fator 2 de Crescimento de Fibroblastos/sangue , Hemangioma/tratamento farmacológico , Propranolol/administração & dosagem , Fator A de Crescimento do Endotélio Vascular/sangue , Administração Oral , Antagonistas Adrenérgicos beta/efeitos adversos , Antineoplásicos/efeitos adversos , Biomarcadores Tumorais/sangue , Quimiocina CCL2/sangue , Feminino , Hemangioma/sangue , Hemangioma/diagnóstico , Humanos , Lactente , Recém-Nascido , Masculino , Metaloproteinase 2 da Matriz/sangue , Valor Preditivo dos Testes , Propranolol/efeitos adversos , Estudos Prospectivos , República da Coreia , Fatores de Tempo , Resultado do Tratamento
17.
Clin Exp Pediatr ; 63(4): 141-145, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32024325

RESUMO

BACKGROUND: For children and adolescents with cancer, going back to school is a key milestone in returning to "normal life." PURPOSE: To identify the support vital for a successful transition, we evaluated the parents' needs and the challenges they face when their children return to school. METHODS: This multi-institutional study was conducted by the Korean Society of Pediatric Hematology and Oncology. The written survey comprised 24 questions and was completed by 210 parents without an interviewer. RESULTS: Most parents (165 of 206) reported that their children experienced difficulties with physical status (n=60), peer relationships (n=30), academic performance (n=27), emotional/behavioral issues (n=11), and relationships with teachers (n=4) on reentering school. Parents wanted to be kept informed about and remain involved in their children's school lives and reported good parent-teacher communication (88 of 209, 42.1%). Parents reported that 83.1% and 44.9% of teachers and peers, respectively, displayed an adequate understanding of their children's condition. Most parents (197 of 208) answered that a special program is necessary to facilitate return to school after cancer therapy that offers emotional support (n=85), facilitates social adaptation (n=61), and provides tutoring to accelerate catch up (n=56), and continued health care by hospital outreach and school personnel (n=50). CONCLUSION: In addition to scholastic aptitude-oriented programs, emotional and psychosocial support is necessary for a successful return to school. Pediatric oncologists should actively improve oncology practices to better integrate individualized school plans and educate peers and teachers to improve health literacy to aid them in understanding the needs of children with cancer.

18.
Phys Rev Lett ; 123(23): 236401, 2019 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-31868467

RESUMO

Transition metal phosphorous trichalcogenides, MPX_{3} (M and X being transition metal and chalcogen elements, respectively), have been the focus of substantial interest recently because they are unusual candidates undergoing Mott transition in the two-dimensional limit. Here we investigate material properties of the compounds with M=Mn and Ni employing ab initio density functional and dynamical mean-field calculations, especially their electronic behavior under external pressure in the paramagnetic phase. Mott metal-insulator transitions (MIT) are found to be a common feature for both compounds, but their lattice structures show drastically different behaviors depending on the relevant orbital degrees of freedom, i.e., t_{2g} or e_{g}. Under pressure, MnPS_{3} can undergo an isosymmetric structural transition within monoclinic space group by forming Mn-Mn dimers due to the strong direct overlap between the neighboring t_{2g} orbitals, accompanied by a significant volume collapse and a spin-state transition. In contrast, NiPS_{3} and NiPSe_{3}, with their active e_{g} orbital degrees of freedom, do not show a structural change at the MIT pressure or deep in the metallic phase within the monoclinic symmetry. Hence NiPS_{3} and NiPSe_{3} become rare examples of materials hosting electronic bandwidth-controlled Mott MITs, thus showing promise for ultrafast resistivity switching behavior.

19.
Brain Tumor Res Treat ; 7(2): 92-97, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31686439

RESUMO

BACKGROUND: Pilocytic astrocytoma (PA) is a brain tumor that is relatively more common in children and young adults. METHODS: We retrospectively reviewed the medical records of patients with PA treated at a single center between 1988 and 2018. RESULTS: We included 31 subjects with PA. The median age at diagnosis was 13.4 years, and the median follow-up duration was 9.9 years. The total PA group had a 10-year disease-specific survival (DSS) rate of 92.6% [95% confidence interval (CI), 82.6-100] and 10-year progression-free survival (PFS) rate of 52.8% (95% CI, 32.0-73.6). In patients aged <20 years, tumors were more likely to be located in sites in which gross total tumor resection (GTR) was impossible. No statistically significant difference in 10-year DSS was found between the GTR (100%) and non-GTR (89.7%; 95% CI, 76.2-100; p=0.374) groups. However, a statistically significant difference in 10-year PFS was found between the GTR (100%) and non-GTR groups (30.7%; 95% CI, 8.6-52.8; p=0.012). In the non-GTR group, no statistically significant difference in 10-year DSS was found between the patients who received immediate additional chemotherapy and/or radiotherapy (Add-Tx group, 92.9%; 95% CI, 79.4-100) and the non-Add-Tx group (83.3%; 95% CI, 53.5-100; p=0.577). No statistically significant difference in 10-year PFS was found between the Add-Tx group (28.9%; 95% CI, 1.7-56.1) and non-Add-Tx group (33.3%; 95% CI, 0-70.9; p=0.706). CONCLUSION: The PFS of the patients with PA in our study depended only on the degree of surgical excision associated with tumor location. This study is limited by its small number of patients and retrospective nature. A multicenter and prospective study is necessary to confirm these findings.

20.
Proc Natl Acad Sci U S A ; 116(40): 19863-19868, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31527227

RESUMO

We investigate [Formula: see text]/[Formula: see text] superlattices in which we observe a full electron transfer at the interface from Ir to Ni, triggering a massive structural and electronic reconstruction. Through experimental characterization and first-principles calculations, we determine that a large crystal field splitting from the distorted interfacial [Formula: see text] octahedra surprisingly dominates over the spin-orbit coupling and together with the Hund's coupling results in the high-spin (S = 1) configurations on both the Ir and Ni sites. This demonstrates the power of interfacial charge transfer in coupling lattice, charge, orbital, and spin degrees of freedom, opening fresh avenues of investigation of quantum states in oxide superlattices.

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