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1.
Immunity ; 2024 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-39236718

RESUMEN

Lymphocyte activation gene 3 (Lag3) is an inhibitory co-receptor expressed on activated T cells and has been proposed to regulate regulatory T (Treg) cell function. However, its precise modality and mechanisms remain elusive. We generated Treg cell-specific Lag3-mutant mouse models and found that Lag3 was essential for Treg cell control of autoimmunity. RNA sequencing analysis revealed that Lag3 mutation altered genes associated with metabolic processes, especially Myc target genes. Myc expression in Lag3-mutant Treg cells was increased to the level seen in conventional T helper (Th)1-type effector cells and directly correlated with their metabolic profiles and in vivo suppressive functions. The phosphatidylinositol 3-kinase (PI3K)-Akt-Rictor pathway was activated in Lag3-mutant Treg cells, and inhibiting PI3K, Rictor, or lactate dehydrogenase A (Ldha), a key Myc target enzyme converting pyruvate to lactate, was sufficient to restore normal metabolism and suppressive function in Lag3-mutant Treg cells. These findings indicate that Lag3 supports Treg cell suppression partly by tuning Myc-dependent metabolic programming.

2.
Nature ; 626(7999): 626-634, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38326614

RESUMEN

Adoptive T cell therapies have produced exceptional responses in a subset of patients with cancer. However, therapeutic efficacy can be hindered by poor T cell persistence and function1. In human T cell cancers, evolution of the disease positively selects for mutations that improve fitness of T cells in challenging situations analogous to those faced by therapeutic T cells. Therefore, we reasoned that these mutations could be co-opted to improve T cell therapies. Here we systematically screened the effects of 71 mutations from T cell neoplasms on T cell signalling, cytokine production and in vivo persistence in tumours. We identify a gene fusion, CARD11-PIK3R3, found in a CD4+ cutaneous T cell lymphoma2, that augments CARD11-BCL10-MALT1 complex signalling and anti-tumour efficacy of therapeutic T cells in several immunotherapy-refractory models in an antigen-dependent manner. Underscoring its potential to be deployed safely, CARD11-PIK3R3-expressing cells were followed up to 418 days after T cell transfer in vivo without evidence of malignant transformation. Collectively, our results indicate that exploiting naturally occurring mutations represents a promising approach to explore the extremes of T cell biology and discover how solutions derived from evolution of malignant T cells can improve a broad range of T cell therapies.


Asunto(s)
Evolución Molecular , Inmunoterapia Adoptiva , Linfoma Cutáneo de Células T , Mutación , Linfocitos T , Humanos , Proteínas Adaptadoras de Señalización CARD/genética , Proteínas Adaptadoras de Señalización CARD/metabolismo , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD4-Positivos/metabolismo , Citocinas/biosíntesis , Citocinas/inmunología , Citocinas/metabolismo , Guanilato Ciclasa/genética , Guanilato Ciclasa/metabolismo , Inmunoterapia Adoptiva/métodos , Linfoma Cutáneo de Células T/genética , Linfoma Cutáneo de Células T/inmunología , Linfoma Cutáneo de Células T/patología , Linfoma Cutáneo de Células T/terapia , Fosfatidilinositol 3-Quinasas , Transducción de Señal/genética , Linfocitos T/inmunología , Linfocitos T/metabolismo , Linfocitos T/trasplante
3.
Nature ; 631(8022): 857-866, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38987586

RESUMEN

Systemic lupus erythematosus (SLE) is prototypical autoimmune disease driven by pathological T cell-B cell interactions1,2. Expansion of T follicular helper (TFH) and T peripheral helper (TPH) cells, two T cell populations that provide help to B cells, is a prominent feature of SLE3,4. Human TFH and TPH cells characteristically produce high levels of the B cell chemoattractant CXCL13 (refs. 5,6), yet regulation of T cell CXCL13 production and the relationship between CXCL13+ T cells and other T cell states remains unclear. Here, we identify an imbalance in CD4+ T cell phenotypes in patients with SLE, with expansion of PD-1+/ICOS+ CXCL13+ T cells and reduction of CD96hi IL-22+ T cells. Using CRISPR screens, we identify the aryl hydrocarbon receptor (AHR) as a potent negative regulator of CXCL13 production by human CD4+ T cells. Transcriptomic, epigenetic and functional studies demonstrate that AHR coordinates with AP-1 family member JUN to prevent CXCL13+ TPH/TFH cell differentiation and promote an IL-22+ phenotype. Type I interferon, a pathogenic driver of SLE7, opposes AHR and JUN to promote T cell production of CXCL13. These results place CXCL13+ TPH/TFH cells on a polarization axis opposite from T helper 22 (TH22) cells and reveal AHR, JUN and interferon as key regulators of these divergent T cell states.


Asunto(s)
Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico , Linfocitos T CD4-Positivos , Quimiocina CXCL13 , Interferón Tipo I , Lupus Eritematoso Sistémico , Proteínas Proto-Oncogénicas c-jun , Receptores de Hidrocarburo de Aril , Femenino , Humanos , Masculino , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD4-Positivos/metabolismo , Diferenciación Celular , Quimiocina CXCL13/metabolismo , Epigenómica , Perfilación de la Expresión Génica , Interferón Tipo I/inmunología , Interferón Tipo I/metabolismo , Interleucina-22/inmunología , Interleucina-22/metabolismo , Lupus Eritematoso Sistémico/inmunología , Lupus Eritematoso Sistémico/metabolismo , Lupus Eritematoso Sistémico/genética , Proteínas Proto-Oncogénicas c-jun/metabolismo , Receptores de Hidrocarburo de Aril/metabolismo , Linfocitos T Colaboradores-Inductores/inmunología , Linfocitos T Colaboradores-Inductores/metabolismo
4.
J Immunol ; 212(12): 1867-1876, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38647384

RESUMEN

Allergic airway inflammation results from uncontrolled immune responses to environmental Ags. Although it is well established that allergic immune responses exhibit a high degree of diversity, driven by primary effector cell types such as eosinophils, neutrophils, or CD4 T cells with distinct effector signatures, the mechanisms responsible for such pathogenesis remain elusive. Foxp3+ regulatory T cells (Tregs) are essential immune regulators during chronic inflammation, including allergic airway inflammation. Emerging evidence suggests that Tregs infiltrating inflamed tissues exhibit distinct phenotypes dependent on the specific tissue sites and can display heterogeneity and tissue residency. Whether diverse allergic airway inflammatory responses influence infiltrating Treg heterogeneity or Treg lung residency has not been explored. We employed an unbiased single-cell RNA sequencing approach to investigate lung-infiltrating Tregs in models of eosinophilic and neutrophilic airway inflammation. We found that lung-infiltrating Tregs are highly heterogeneous, and that Tregs displaying lung-resident phenotypes are significantly different depending on the types of inflammation. Treg expression of ST2, a receptor for alarmin IL-33, was predominantly associated with eosinophilic inflammation and tissue residency. Nevertheless, Treg-specific ST2 deficiency did not affect the development of eosinophilic allergic inflammation or the generation of lung-resident Tregs. These results uncover a stark heterogeneity among Tregs infiltrating the lungs during allergic airway inflammation. The results indicate that varying types of inflammation may give rise to phenotypically distinct lung-resident Tregs, underscoring a (to our knowledge) novel mechanism by which inflammatory cues may shape the composition of infiltrating Tregs, allowing them to regulate inflammatory responses through tissue-adapted mechanisms.


Asunto(s)
Eosinófilos , Pulmón , Neutrófilos , Análisis de la Célula Individual , Linfocitos T Reguladores , Linfocitos T Reguladores/inmunología , Animales , Ratones , Neutrófilos/inmunología , Eosinófilos/inmunología , Pulmón/inmunología , Pulmón/patología , Ratones Endogámicos C57BL , Proteína 1 Similar al Receptor de Interleucina-1/genética , Proteína 1 Similar al Receptor de Interleucina-1/inmunología , Ratones Noqueados , Inflamación/inmunología , Modelos Animales de Enfermedad , Interleucina-33/inmunología , Eosinofilia/inmunología , Eosinofilia/patología
5.
J Immunol ; 211(10): 1450-1458, 2023 11 15.
Artículo en Inglés | MEDLINE | ID: mdl-37931208

RESUMEN

Mature T cell lymphomas are heterogeneous neoplasms that are aggressive and resistant to treatment. Many of these cancers retain immunological properties of their cell of origin. They express cytokines, cytotoxic enzymes, and cell surface ligands normally induced by TCR signaling in untransformed T cells. Until recently, their molecular mechanisms were unclear. Recently, high-dimensional studies have transformed our understanding of their cellular and genetic characteristics. Somatic mutations in the TCR signaling pathway drive lymphomagenesis by disrupting autoinhibitory domains, increasing affinity to ligands, and/or inducing TCR-independent signaling. Collectively, most of these mutations augment signaling pathways downstream of the TCR. Emerging data suggest that these mutations not only drive proliferation but also determine lymphoma immunophenotypes. For example, RHOA mutations are sufficient to induce disease-relevant CD4+ T follicular helper cell phenotypes. In this review, we describe how mutations in the TCR signaling pathway elucidate lymphoma pathophysiology but also provide insights into broader T cell biology.


Asunto(s)
Linfoma de Células T , Linfoma , Humanos , Linfoma/genética , Mutación , Transducción de Señal , Receptores de Antígenos de Linfocitos T/metabolismo
7.
Haematologica ; 2024 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-39113648

RESUMEN

Adult T-cell leukemia-lymphoma (ATLL) is an aggressive Human T-cell Leukemia Virus Type 1 (HTLV-1)-driven malignancy. Although Western hemisphere (Afro-Caribbean and South American) patients face worse prognoses, our understanding of ATLL molecular drivers derives mostly from Japanese studies. We performed multi-omic analyses to elucidate the genomic landscape of ATLL in Western cohorts. Recurrent deletion and/or damaging mutations involving FOXO3, ANKRD11, DGKZ, and PTPN6 implicate these genes as potential tumor suppressors. RNA-seq, published functional data and in vitro assays support the roles of ANKRD11 and FOXO3 as regulators of T-cell proliferation and apoptosis in ATLL, respectively. Survival data suggest ANKRD11 mutation may confer a worse prognosis. Japanese and Western cohorts, in addition to acute and lymphomatous subtypes, demonstrated distinct molecular patterns. GATA3 deletion was associated with unfavorable chronic cases. IRF4 and CARD11 mutations frequently emerged in relapses after interferon therapy. Our findings reveal novel putative ATLL driver genes and clinically relevant differences between Japanese and Western ATLL patients.

8.
J Cutan Pathol ; 51(6): 459-467, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38443749

RESUMEN

BACKGROUND: Interstitial mycosis fungoides (IMF) is a rare subtype of mycosis fungoides (MF) characterized by atypical lymphocytes infiltrating the reticular dermis between collagen bundles with limited epidermotropism and variable granulomatous features. METHODS: Retrospective single institution review of 31 cases of IMF including clinical characteristics, disease course and pathological features. RESULTS: Our cohort was predominately male (19; 61%, M:F 1.6:1) with a mean age at diagnosis of 43 years (range 11-85), mean signs/symptoms duration of 7 years prior to diagnosis, and 6 years mean follow-up duration. Clinically, patients often exhibited symmetric ill-defined patches/plaques involving intertriginous regions with tan-yellow hyperpigmentation and follicular-based papules, wrinkling, and alopecia. Lymphadenopathy was noted in seven patients. Fifteen (52%) patients were in near or complete clinical remission at the latest follow-up. T-cell receptor gene rearrangement was positive in 23/24 (96%) cases. Histopathologically, atypical cells were small-medium, CD4+ (29; 94%) or rarely CD4+/CD8+ (1; 3%) lymphocytes infiltrating the reticular dermis with thickened collagen bundles (27; 87%), multinucleated giant cells (12; 39%), and often tracing along adnexa with subtle folliculotropism (12/20; 60%). CONCLUSIONS: Our study demonstrates IMF is an indolent subtype of MF with distinct features, including frequent granulomatous and subtle follicular involvement resulting in alopecia.


Asunto(s)
Micosis Fungoide , Neoplasias Cutáneas , Humanos , Micosis Fungoide/patología , Micosis Fungoide/diagnóstico , Masculino , Femenino , Persona de Mediana Edad , Adulto , Anciano , Neoplasias Cutáneas/patología , Estudios Retrospectivos , Anciano de 80 o más Años , Adolescente , Niño , Folículo Piloso/patología
9.
J Pharmacol Exp Ther ; 384(2): 277-286, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36410792

RESUMEN

Extensive bowel resection caused by various diseases that affect the intestines, such as Crohn's disease, volvulus, and cancer, leads to short bowel syndrome (SBS). Teduglutide is the only approved glucagon-like peptide-2 (GLP-2) drug for SBS; however, it requires daily administration. A novel GLP-2 analog with a prolonged duration of action to reduce dosing frequency and promote a greater efficacy may provide patients with a better quality of life. In the present study, the sustained exposure of HM15912 was characterized in normal male rats. The efficacy of HM15912 on intestinal growth and absorption capacity was also evaluated in normal male mice, rats, and SBS rats. HM15912 exhibited a remarkably extended half-life (42.3 hours) compared with teduglutide (0.6 hours) in rats. Despite somewhat lower in vitro potency on GLP-2 receptor than human GLP-2 or teduglutide, this longer-lasting mode of action promotes HM15912 to be more effective in terms of small intestinal growth than existing GLP-2 analogs even with a less frequent dosing interval of as little as once a week in rodents, including SBS rats. Furthermore, the small intestinal weight was approximately doubled, and the D-xylose absorption was significantly increased after pre-treatment of existing GLP-2 analogs on the market or under clinical development followed by HM15912 in rodents. These results indicate that HM15912 possesses a significant small bowel trophic effect driven by continuously increased exposure, supporting that HM15912 may be a novel treatment option with greater efficacy and the longest dosing interval among existing GLP-2 analogs for SBS with intestinal failure. SIGNIFICANCE STATEMENT: HM15912, a novel long-acting glucagon-like peptide-2 (GLP-2) analog, has a significant small bowel hypertrophic effect in rodents with a reduced frequency of administration compared to the existing GLP-2 analogs on the market or currently under clinical development. This study supports the possibility that HM15912 could be administered much less frequently than other long-acting GLP-2 analogs for patients with short bowel syndrome.


Asunto(s)
Síndrome del Intestino Corto , Animales , Humanos , Masculino , Ratones , Ratas , Péptido 2 Similar al Glucagón/farmacología , Absorción Intestinal , Intestino Delgado , Intestinos , Calidad de Vida , Síndrome del Intestino Corto/tratamiento farmacológico
10.
Blood ; 138(14): 1225-1236, 2021 10 07.
Artículo en Inglés | MEDLINE | ID: mdl-34115827

RESUMEN

Cutaneous T-cell lymphomas (CTCLs) are a clinically heterogeneous collection of lymphomas of the skin-homing T cell. To identify molecular drivers of disease phenotypes, we assembled representative samples of CTCLs from patients with diverse disease subtypes and stages. Via DNA/RNA-sequencing, immunophenotyping, and ex vivo functional assays, we identified the landscape of putative driver genes, elucidated genetic relationships between CTCLs across disease stages, and inferred molecular subtypes in patients with stage-matched leukemic disease. Collectively, our analysis identified 86 putative driver genes, including 19 genes not previously implicated in this disease. Two mutations have never been described in any cancer. Functionally, multiple mutations augment T-cell receptor-dependent proliferation, highlighting the importance of this pathway in lymphomagenesis. To identify putative genetic causes of disease heterogeneity, we examined the distribution of driver genes across clinical cohorts. There are broad similarities across disease stages. Many driver genes are shared by mycosis fungoides (MF) and Sezary syndrome (SS). However, there are significantly more structural variants in leukemic disease, leading to highly recurrent deletions of putative tumor suppressors that are uncommon in early-stage skin-centered MF. For example, TP53 is deleted in 7% and 87% of MF and SS, respectively. In both human and mouse samples, PD1 mutations drive aggressive behavior. PD1 wild-type lymphomas show features of T-cell exhaustion. PD1 deletions are sufficient to reverse the exhaustion phenotype, promote a FOXM1-driven transcriptional signature, and predict significantly worse survival. Collectively, our findings clarify CTCL genetics and provide novel insights into pathways that drive diverse disease phenotypes.


Asunto(s)
Linfoma Cutáneo de Células T/genética , Transcriptoma , Animales , Células Cultivadas , Proteína Forkhead Box M1/genética , Regulación Neoplásica de la Expresión Génica , Genes Supresores de Tumor , Humanos , Ratones , Mutación , Oncogenes , Proteína p53 Supresora de Tumor/genética
11.
Diabetes Obes Metab ; 25(9): 2723-2733, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37311732

RESUMEN

AIM: To evaluate the safety, tolerability, pharmacokinetics and pharmacodynamics of multiple ascending doses of the novel long-acting glucagon analogue HM15136 in overweight/obese patients with co-morbidities, with and without type 2 diabetes (T2D). MATERIALS AND METHODS: This was a phase 1, double-blind, randomized, placebo-controlled, two-part trial with a 12-week treatment period of once-weekly subcutaneous HM15136 (0.02/0.04/0.06 mg/kg). Part 1 included patients with dyslipidaemia and/or hypertension and no T2D. Part 2 included patients with dyslipidaemia and/or hypertension plus T2D. RESULTS: In part 1, 23/27 (85.2%) patients receiving HM15136 and all patients receiving placebo (9/9 [100%]) experienced a treatment-emergent adverse event (TEAE). Five of 27 (18.5%) patients receiving HM15136 developed anti-HM15136 antibodies. Dose-dependent increases in mean HM15136 serum concentration and fasting plasma glucose (FPG) were observed, as were dose-dependent weight reductions of 0.5%/2.3%/2.6% at doses of 0.02/0.04/0.06 mg/kg, respectively. In part 2, 8/12 (66.7%) patients receiving HM15136 and all patients receiving placebo (4/4 [100.0%]) reported a TEAE. Two (16.7%) patients developed anti-HM15136 antibodies. Dose-dependent increases in mean HM15136 serum concentration were observed. FPG of more than 200 mg/dL was reported in 4/9 (44.4%) and 2/3 (66.7%) patients receiving 0.02 and 0.06 mg/kg, respectively. The 0.06 mg/kg dose was not tolerated in part 2 because of hyperglycaemia. Patients receiving 0.02 mg/kg showed a 0.9% weight reduction. No serious TEAEs leading to discontinuation were reported in either study part. CONCLUSIONS: This study of HM15136 provides a preliminary safety and tolerability profile with initial insights into its efficacy profile.


Asunto(s)
Diabetes Mellitus Tipo 2 , Hipertensión , Humanos , Sobrepeso/complicaciones , Sobrepeso/tratamiento farmacológico , Sobrepeso/inducido químicamente , Glucagón/uso terapéutico , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Hipoglucemiantes , Glucemia , Obesidad/complicaciones , Obesidad/tratamiento farmacológico , Obesidad/inducido químicamente , Pérdida de Peso , Hipertensión/tratamiento farmacológico , Hipertensión/inducido químicamente , Morbilidad , Método Doble Ciego , Relación Dosis-Respuesta a Droga
12.
J Am Acad Dermatol ; 88(2): 329-337, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36265823

RESUMEN

BACKGROUND: Sepsis is a leading cause of morbidity, mortality, and resource utilization among patients with cutaneous T-cell lymphoma (CTCL). OBJECTIVE: To characterize the demographic, clinical, and microbial attributes distinguishing patients with CTCL sepsis from other patients with non-Hodgkin lymphoma (NHL) sepsis and patients with CTCL in general. METHODS: Two-part retrospective cohort study at an academic medical center from 2001-2019 involving patients with CTCL (n = 97) and non-CTCL NHL (n = 88) admitted with sepsis, and a same-institution CTCL patient database (n = 1094). Overall survival was estimated by Kaplan-Meier analyses. RESULTS: Patients with CTCL sepsis were more likely to be older, Black, experience more sepsis episodes, die or be readmitted within 30 days of an inpatient sepsis episode, and develop Gram-positive bacteremia than patients with non-CTCL NHL sepsis. Staphylococcus aureus and Escherichia coli were the most frequently speciated organisms in CTCL (26%) and non-CTCL NHL (14%), respectively. No between-group differences were identified regarding sex, presence of central line, chemotherapy use, or disease stage. Compared with general patients with CTCL, patients with sepsis were Black and exhibited advanced-stage disease, higher body surface area involvement, and higher lactate dehydrogenase levels. LIMITATIONS: Single institution, retrospective nature may limit generalizability. CONCLUSION: Awareness of CTCL-specific risk factors is crucial for guiding sepsis prevention and improving patient outcomes.


Asunto(s)
Linfoma no Hodgkin , Linfoma Cutáneo de Células T , Sepsis , Neoplasias Cutáneas , Humanos , Estudios Retrospectivos , Neoplasias Cutáneas/patología , Linfoma Cutáneo de Células T/complicaciones , Linfoma Cutáneo de Células T/epidemiología , Sepsis/epidemiología
13.
J Immunol ; 207(3): 765-770, 2021 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-34301840

RESUMEN

Glucocorticoids are a highly effective first-line treatment option for many inflammatory diseases, including asthma. Some patients develop a steroid-resistant condition, yet, the cellular and molecular mechanisms underlying steroid resistance remain largely unknown. In this study, we used a murine model of steroid-resistant airway inflammation and report that combining systemic dexamethasone and intranasal IL-27 is able to reverse the inflammation. Foxp3+ regulatory T cells (Tregs) were required during dexamethasone/IL-27 treatment of steroid-resistant allergic inflammation, and importantly, direct stimulation of Tregs via glucocorticoid or IL-27 receptors was essential. Mechanistically, IL-27 stimulation in Tregs enhanced expression of the agonistic glucocorticoid receptor-α isoform. Overexpression of inhibitory glucocorticoid receptor-ß isoform in Tregs alone was sufficient to elicit steroid resistance in a steroid-sensitive allergic inflammation model. Taken together, our results demonstrate for the first time, to our knowledge, that Tregs are instrumental during steroid resistance and that manipulating steroid responsiveness in Tregs may represent a novel strategy to treat steroid refractory asthma.


Asunto(s)
Asma/inmunología , Dexametasona/uso terapéutico , Interleucina-27/uso terapéutico , Hipersensibilidad Respiratoria/inmunología , Linfocitos T Reguladores/inmunología , Alérgenos/inmunología , Animales , Asma/tratamiento farmacológico , Células Cultivadas , Modelos Animales de Enfermedad , Resistencia a Medicamentos , Factores de Transcripción Forkhead/genética , Factores de Transcripción Forkhead/metabolismo , Humanos , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Ovalbúmina/inmunología , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Receptores de Glucocorticoides/genética , Receptores de Glucocorticoides/metabolismo , Hipersensibilidad Respiratoria/tratamiento farmacológico
14.
Sensors (Basel) ; 23(14)2023 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-37514930

RESUMEN

Improving the operational efficiency and optimizing the design of sound navigation and ranging (sonar) systems require accurate electrical equivalent models within the operating frequency range. The power conversion system within the sonar system increases power efficiency through impedance-matching circuits. Impedance matching is used to enhance the power transmission efficiency of the sonar system. Therefore, to increase the efficiency of the sonar system, an electrical-matching circuit is employed, and this necessitates an accurate equivalent circuit for the sonar transducer within the operating frequency range. In conventional equivalent circuit derivation methods, errors occur because they utilize the same number of RLC branches as the resonant frequency of the sonar transducer, based on its physical properties. Hence, this paper proposes an algorithm for deriving an equivalent circuit independent of resonance by employing multiple electrical components and particle swarm optimization (PSO). A comparative verification was also performed between the proposed and existing approaches using the Butterworth-van Dyke (BVD) model, which is a method for deriving electrical equivalent circuits.

15.
Plant Dis ; 2022 Dec 08.
Artículo en Inglés | MEDLINE | ID: mdl-36480734

RESUMEN

In June 2020, brown spot symptoms were observed in a commercial potato field located in Yeocheon, Gyeonggi Province, Korea. The symptoms were similar to those associated with early blight. Brown lesions on leaves were circular and expanded rapidly under high humidity and warm temperatures ranging 12°C at night to 30°C during daytime. Over 60% of potato (Solanum tuberosum L. cv. Superior) leaves showed the symptoms. For fungal isolation, infected leaf tissues (5 × 5 mm) from 14 infected samples were immersed in 70% ethanol for 1 min, rinsed three times in sterilized water, dried, placed on water agar amended with 100 ppm of streptomycin, and then incubated in the dark at 25°C. Hyphae emerging from the tissues were subcultured on V8-Juice agar (8% of V8-Juice, 1.5% agar, pH 7), and the obtaining cultures were subjected to single-spore isolation, resulting in 14 isolates (SYP-934~947). Three representative isolates, SYP-934 to SYP-936, were deposited in the Korean Agriculture Culture Collection (Accession Nos. KACC 410058 to KACC 410060). Conidia (n = 100) produced on the colony were brown, ellipsoid to ovoid with walls ornamented, 1 to 6 transverse and 0-3 vertical septa, and length × width of 20-45 × 7 to 24 µm (n = 100). Their morphological characteristics were consistent with Alternaria alternata (Simmons, 2007; van der Waals et al., 2011; Woundenberg et al. 2015). Sequences of the following loci in the 14 isolates were determined as described in Woundenberg et al. (2013 and 2014: the internal transcribed spacer (primer pairs VG9/ITS4, GenBank accession nos. OP581413-25), glyceraldehyde-3-phosphate dehydrogenase (gpd1/gpd2, OP588286-99), RNA polymerase second largest subunit (RPB2-5F2/fRPB2-7cR, OP588314-27), translation elongation factor 1-alpha (EF1-728F/EF1-986R, OP588300-13), Alternaria major allergen gene (Alt-For/Alt-Rev, OP588328-41), endopolygalacturonase (PG3/PG2b, OP588342-55), and an unknown gene region (OPA10-2R/OPA10-2L, OP588356-68). A neighbor-joining phylogenetic analysis based on the concatenated gene sequences, which was performed using the MEGA X program (Kumar et al., 2018), placed the 14 isolates in the clade containing A. alternata isolates. To test pathogenicity, one-month-old potato (S. tuberosum cv. Superior) plants grown in a 25°C growth chamber were sprayed with conidial suspensions (1×106 conidia/mL) prepared from 14-day-old cultures of three isolates (KACC 410058 to KACC 410060). Sterile distilled water was used as the control treatment. The inoculated pots were placed in a plastic box to maintain high humidity and incubated in the dark at 25°C for 2 days. The plants were transferred to a growth chamber (16h light with over 70% humidity at 25°C). Symptoms were first observed after 3 days post inoculation (dpi) with all three isolates, and severe brown spot symptoms were observed after 7 dpi. No symptom was observed in the control treatment. The pathogenicity assay was repeated at triplicate. Reisolated cultures from lesions were confirmed to be A. alternata based on their sequence at the rpb2 locus, thus fulfilling Koch's postulates. Alternaria alternata has been reported to cause brown spot and leaf blight on potato leaves in Israel (Dorby et al., 1984) and South Africa (van der Waals., et al. 2011). To our knowledge, this study is the first report of A. alternata causing brown spot disease in Korea.

16.
Sensors (Basel) ; 22(14)2022 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-35890945

RESUMEN

Multi-Target Multi-Camera Tracking (MTMCT), which aims to track multiple targets within a multi-camera network, has recently attracted considerable attention due to its wide range of applications. The main challenge of MTMCT is to match local tracklets (i.e., sub-trajectories) obtained by different cameras and to combine them into global trajectories across the multi-camera network. This paper addresses the cross-camera tracklet matching problem in scenarios with partially overlapping fields of view (FOVs), such as indoor multi-camera environments. We present a new lightweight matching method for the MTMC task that employs similarity analysis for location features. The proposed approach comprises two steps: (i) extracting the motion information of targets based on a ground projection method and (ii) matching the tracklets using similarity analysis based on the Dynamic Time Warping (DTW) algorithm. We use a Kanade-Lucas-Tomasi (KLT) algorithm-based frame-skipping method to reduce the computational overhead in object detection and to produce a smooth estimate of the target's local tracklets. To improve matching accuracy, we also investigate three different location features to determine the most appropriate feature for similarity analysis. The effectiveness of the proposed method has been evaluated through real experiments, demonstrating its ability to accurately match local tracklets.


Asunto(s)
Algoritmos , Movimiento (Física)
17.
Sensors (Basel) ; 22(2)2022 Jan 07.
Artículo en Inglés | MEDLINE | ID: mdl-35062397

RESUMEN

Distinguishing between wireless and wired traffic in a network middlebox is an essential ingredient for numerous applications including security monitoring and quality-of-service (QoS) provisioning. The majority of existing approaches have exploited the greater delay statistics, such as round-trip-time and inter-packet arrival time, observed in wireless traffic to infer whether the traffic is originated from Ethernet (i.e., wired) or Wi-Fi (i.e., wireless) based on the assumption that the capacity of the wireless link is much slower than that of the wired link. However, this underlying assumption is no longer valid due to increases in wireless data rates over Gbps enabled by recent Wi-Fi technologies such as 802.11ac/ax. In this paper, we revisit the problem of identifying Wi-Fi traffic in network middleboxes as the wireless link capacity approaches the capacity of the wired. We present Weigh-in-Motion, a lightweight online detection scheme, that analyzes the traffic patterns observed at the middleboxes and infers whether the traffic is originated from high-speed Wi-Fi devices. To this end, we introduce the concept of ACKBunch that captures the unique characteristics of high-speed Wi-Fi, which is further utilized to distinguish whether the observed traffic is originated from a wired or wireless device. The effectiveness of the proposed scheme is evaluated via extensive real experiments, demonstrating its capability of accurately identifying wireless traffic from/to Gigabit 802.11 devices.

18.
Sensors (Basel) ; 22(23)2022 Nov 24.
Artículo en Inglés | MEDLINE | ID: mdl-36501813

RESUMEN

Gait-based gender classification is a challenging task since people may walk in different directions with varying speed, gait style, and occluded joints. The majority of research studies in the literature focused on gender-specific joints, while there is less attention on the comparison of all of a body's joints. To consider all of the joints, it is essential to determine a person's gender based on their gait using a Kinect sensor. This paper proposes a logistic-regression-based machine learning model using whole body joints for gender classification. The proposed method consists of different phases including gait feature extraction based on three dimensional (3D) positions, feature selection, and classification of human gender. The Kinect sensor is used to extract 3D features of different joints. Different statistical tools such as Cronbach's alpha, correlation, t-test, and ANOVA techniques are exploited to select significant joints. The Coronbach's alpha technique yields an average result of 99.74%, which indicates the reliability of joints. Similarly, the correlation results indicate that there is significant difference between male and female joints during gait. t-test and ANOVA approaches demonstrate that all twenty joints are statistically significant for gender classification, because the p-value for each joint is zero and less than 1%. Finally, classification is performed based on the selected features using binary logistic regression model. A total of hundred (100) volunteers participated in the experiments in real scenario. The suggested method successfully classifies gender based on 3D features recorded in real-time using machine learning classifier with an accuracy of 98.0% using all body joints. The proposed method outperformed the existing systems which mostly rely on digital images.


Asunto(s)
Algoritmos , Trastornos Neurológicos de la Marcha , Humanos , Masculino , Femenino , Reproducibilidad de los Resultados , Marcha , Aprendizaje Automático , Articulaciones
19.
Sensors (Basel) ; 22(23)2022 Dec 02.
Artículo en Inglés | MEDLINE | ID: mdl-36502152

RESUMEN

Although hydraulic accumulators play a vital role in the hydraulic system, they face the challenges of being broken by continuous abnormal pulsating pressure which occurs due to the malfunction of hydraulic systems. Hence, this study develops anomaly detection algorithms to detect abnormalities of pulsating pressure for hydraulic accumulators. A digital pressure sensor was installed in a hydraulic accumulator to acquire the pulsating pressure data. Six anomaly detection algorithms were developed based on the acquired data. A threshold averaging algorithm over a period based on the averaged maximum/minimum thresholds detected anomalies 2.5 h before the hydraulic accumulator failure. In the support vector machine (SVM) and XGBoost model that distinguish normal and abnormal pulsating pressure data, the SVM model had an accuracy of 0.8571 on the test set and the XGBoost model had an accuracy of 0.8857. In a convolutional neural network (CNN) and CNN autoencoder model trained with normal and abnormal pulsating pressure images, the CNN model had an accuracy of 0.9714, and the CNN autoencoder model correctly detected the 8 abnormal images out of 11 abnormal images. The long short-term memory (LSTM) autoencoder model detected 36 abnormal data points in the test set.


Asunto(s)
Redes Neurales de la Computación , Máquina de Vectores de Soporte , Factores de Tiempo , Algoritmos
20.
Biologicals ; 69: 49-58, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33277119

RESUMEN

FGF21 (Fibroblast Growth Factor 21), which is expressed in the liver, adipose tissue, and pancreas, has been widely known as a therapeutic candidate for metabolic diseases. Though FGF21 is crucial to glucose, lipid, and energy homeostasis, it is not straightforward to develop a new drug with FGF21 due to its short half-life in serum. Here, we derived a novel long-acting FGF21 (LAPS-FGF21), which is chemically conjugated to the human IgG4 Fc fragment for longer half-life in serum. The recombinant human IgG4 Fc fragment and FGF21 were prepared by the refolding of inclusion body and periplasmic expression in Escherichia coli overexpression systems, respectively. The efficacy study of LAPS-FGF21 in a Diet-Induced Obesity (DIO) mouse model revealed that LAPS-FGF21 reduced body weight effectively accompanied by improved glucose tolerance in a dose-dependent manner. The administration of LAPS-FGF21 also improved the blood profiles with a significant reduction in cholesterol and triglyceride levels. Additionally, the pharmacokinetic (PK) studies of LAPS-FGF21 using normal ICR mice demonstrated that the half-life of LAPS-FGF21 was approximately 64-fold longer than FGF21. Taken together, the LAPS-FGF21 could be a feasible drug candidate with excellent bodyweight loss efficacy and longer dosing interval by half-life increase in serum.


Asunto(s)
Factores de Crecimiento de Fibroblastos/uso terapéutico , Obesidad , Animales , Glucosa , Humanos , Fragmentos Fc de Inmunoglobulinas , Inmunoglobulina G , Ratones , Ratones Endogámicos ICR , Obesidad/tratamiento farmacológico , Proteínas Recombinantes
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