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1.
Cell Mol Life Sci ; 81(1): 38, 2024 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-38214772

RESUMO

During in vitro culture, human pluripotent stem cells (hPSCs) often acquire survival advantages characterized by decreased susceptibility to mitochondrial cell death, known as "culture adaptation." This adaptation is associated with genetic and epigenetic abnormalities, including TP53 mutations, copy number variations, trisomy, and methylation changes. Understanding the molecular mechanisms underlying this acquired survival advantage is crucial for safe hPSC-based cell therapies. Through transcriptome and methylome analysis, we discovered that the epigenetic repression of CHCHD2, a mitochondrial protein, is a common occurrence during in vitro culture using enzymatic dissociation. We confirmed this finding through genetic perturbation and reconstitution experiments in normal human embryonic stem cells (hESCs). Loss of CHCHD2 expression conferred resistance to single cell dissociation-induced cell death, a common stress encountered during in vitro culture. Importantly, we found that the downregulation of CHCHD2 significantly attenuates the activity of Rho-associated protein kinase (ROCK), which is responsible for inducing single cell death in hESCs. This suggests that hESCs may survive routine enzyme-based cell dissociation by downregulating CHCHD2 and thereby attenuating ROCK activity. These findings provide insights into the mechanisms by which hPSCs acquire survival advantages and adapt to in vitro culture conditions.


Assuntos
Células-Tronco Embrionárias Humanas , Células-Tronco Pluripotentes , Humanos , Linhagem Celular , Repressão Epigenética , Variações do Número de Cópias de DNA , Células-Tronco Embrionárias Humanas/metabolismo , Diferenciação Celular , Sobrevivência Celular , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
2.
Breast Cancer Res ; 26(1): 65, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38609935

RESUMO

BACKGROUND: Sentinel lymph node biopsy (SLNB) is recommended for patients with ductal carcinoma in situ (DCIS) undergoing mastectomy, given the concerns regarding upstaging and technical difficulties of post-mastectomy SLNB. However, this may lead to potential overtreatment, considering favorable prognosis and de-escalation trends in DCIS. Data regarding upstaging and axillary lymph node metastasis among these patients remain limited. METHODS: We retrospectively reviewed patients with DCIS who underwent mastectomy with SLNB or axillary lymph node dissection at Gangnam Severance Hospital between January 2010 and December 2021. To explore the feasibility of omitting SLNB, we assessed the rates of DCIS upgraded to invasive carcinoma and axillary lymph node metastasis. Binary Cox regression analysis was performed to identify clinicopathologic factors associated with upstaging and axillary lymph node metastasis. RESULTS: Among 385 patients, 164 (42.6%) experienced an invasive carcinoma upgrade: microinvasion, pT1, and pT2 were confirmed in 53 (13.8%), 97 (25.2%), and 14 (3.6%) patients, respectively. Seventeen (4.4%) patients had axillary lymph node metastasis. Multivariable analysis identified age ≤ 50 years (adjusted odds ratio [OR], 12.73; 95% confidence interval [CI], 1.18-137.51; p = 0.036) and suspicious axillary lymph nodes on radiologic evaluation (adjusted OR, 9.31; 95% CI, 2.06-41.99; p = 0.004) as independent factors associated with axillary lymph node metastasis. Among patients aged > 50 years and/or no suspicious axillary lymph nodes, only 1.7-2.3%) experienced axillary lymph node metastasis. CONCLUSIONS: Although underestimation of the invasive component was relatively high among patients with DCIS undergoing mastectomy, axillary lymph node metastasis was rare. Our findings suggest that omitting SLNB may be feasible for patients over 50 and/or without suspicious axillary lymph nodes on radiologic evaluation.


Assuntos
Neoplasias da Mama , Carcinoma Intraductal não Infiltrante , Humanos , Feminino , Biópsia de Linfonodo Sentinela , Carcinoma Intraductal não Infiltrante/cirurgia , Metástase Linfática , Neoplasias da Mama/cirurgia , Estudos Retrospectivos , Mastectomia
3.
Small ; : e2401364, 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38874055

RESUMO

Limited electrochemical stability windows of conventional carbonate-based electrolytes pose a challenge to support the Lithium (Li)- and manganese (Mn)-rich (LMR) high-voltage cathodes in rechargeable Li-metal batteries (LMBs). To address this issue, a novel localized high-concentration electrolyte (LHCE) composition incorporating LiPF6 and LiTFSI as dual-salts (D-LHCE), tailored for high-voltage (>4.6 Vvs.Li) operation of LMR cathodes in LMBs is introduced. 7Li nuclear magnetic resonance and Raman spectroscopy revealed the characteristics of the solvation structure of D-LHCE. The addition of LiPF6 provides stable Al-current-collector passivation while the addition of LiTFSI improves the stability of D-LHCE by producing a more robust cathode-electrolyte interphase (CEI) on LMR cathode and solid-electrolyte interphase (SEI) on Li-metal anode. As a result, LMR/Li cell, using the D-LHCE, achieved 72.5% capacity retention after 300 cycles, a significant improvement compared to the conventional electrolyte (21.9% after 100 cycles). The stabilities of LMR CEI and Li-metal SEI are systematically analyzed through combined applications of electrochemical impedance spectroscopy and distribution of relaxation times techniques. The results present that D-LHCE concept represents an effective strategy for designing next-generation electrolytes for high-energy and high-voltage LMB cells.

4.
Hepatology ; 2023 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-37976400

RESUMO

BACKGROUND AND AIMS: HCV infection can be successfully managed with antiviral therapies; however, progression to chronic liver disease states, including NAFLD, is common. There is currently no reliable in vitro model for investigating host-viral interactions underlying the link between HCV and NAFLD; although liver organoids (LOs) show promise, they currently lack nonparenchymal cells, which are key to modeling disease progression. APPROACH AND RESULTS: Here, we present a novel, multicellular LO model using a coculture system of macrophages and LOs differentiated from the same human pluripotent stem cells (PSCs). The cocultured macrophages shifted toward a Kupffer-like cell type, the liver-resident macrophages present in vivo , providing a suitable model for investigating NAFLD pathogenesis. With this multicellular Kupffer-like cell-containing LO model, we found that HCV infection led to lipid accumulation in LOs by upregulating host lipogenesis, which was more marked with macrophage coculture. Reciprocally, long-term treatment of LOs with fatty acids upregulated HCV amplification and promoted inflammation and fibrosis. Notably, in our Kupffer-like cell-containing LO model, the effects of 3 drugs for NASH that have reached phase 3 clinical trials exhibited consistent results with the clinical outcomes. CONCLUSIONS: Taken together, we introduced a multicellular LO model consisting of hepatocytes, Kupffer-like cells, and HSCs, which recapitulated host-virus intercommunication and intercellular interactions. With this novel model, we present a physiologically relevant system for the investigation of NAFLD progression in patients with HCV.

5.
Blood ; 139(18): 2797-2815, 2022 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-35286385

RESUMO

Myeloproliferative neoplasms (MPNs) transform to myelofibrosis (MF) and highly lethal acute myeloid leukemia (AML), although the actionable mechanisms driving progression remain elusive. Here, we elucidate the role of the high mobility group A1 (HMGA1) chromatin regulator as a novel driver of MPN progression. HMGA1 is upregulated in MPN, with highest levels after transformation to MF or AML. To define HMGA1 function, we disrupted gene expression via CRISPR/Cas9, short hairpin RNA, or genetic deletion in MPN models. HMGA1 depletion in JAK2V617F AML cell lines disrupts proliferation, clonogenicity, and leukemic engraftment. Surprisingly, loss of just a single Hmga1 allele prevents progression to MF in JAK2V617F mice, decreasing erythrocytosis, thrombocytosis, megakaryocyte hyperplasia, and expansion of stem and progenitors, while preventing splenomegaly and fibrosis within the spleen and BM. RNA-sequencing and chromatin immunoprecipitation sequencing revealed HMGA1 transcriptional networks and chromatin occupancy at genes that govern proliferation (E2F, G2M, mitotic spindle) and cell fate, including the GATA2 master regulatory gene. Silencing GATA2 recapitulates most phenotypes observed with HMGA1 depletion, whereas GATA2 re-expression partially rescues leukemogenesis. HMGA1 transactivates GATA2 through sequences near the developmental enhancer (+9.5), increasing chromatin accessibility and recruiting active histone marks. Further, HMGA1 transcriptional networks, including proliferation pathways and GATA2, are activated in human MF and MPN leukemic transformation. Importantly, HMGA1 depletion enhances responses to the JAK2 inhibitor, ruxolitinib, preventing MF and prolonging survival in murine models of JAK2V617F AML. These findings illuminate HMGA1 as a key epigenetic switch involved in MPN transformation and a promising therapeutic target to treat or prevent disease progression.


Assuntos
Fator de Transcrição GATA2 , Proteína HMGA1a , Leucemia Mieloide Aguda , Transtornos Mieloproliferativos , Mielofibrose Primária , Animais , Proliferação de Células , Cromatina/genética , Fator de Transcrição GATA2/genética , Redes Reguladoras de Genes , Proteína HMGA1a/genética , Proteína HMGA1a/metabolismo , Janus Quinase 2/genética , Janus Quinase 2/metabolismo , Leucemia Mieloide Aguda/genética , Camundongos , Transtornos Mieloproliferativos/genética , Transtornos Mieloproliferativos/metabolismo , Mielofibrose Primária/genética
6.
Mol Cell ; 61(6): 859-73, 2016 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-26990989

RESUMO

Dysregulation of MLL complex-mediated histone methylation plays a pivotal role in gene expression associated with diseases, but little is known about cellular factors modulating MLL complex activity. Here, we report that SON, previously known as an RNA splicing factor, controls MLL complex-mediated transcriptional initiation. SON binds to DNA near transcription start sites, interacts with menin, and inhibits MLL complex assembly, resulting in decreased H3K4me3 and transcriptional repression. Importantly, alternatively spliced short isoforms of SON are markedly upregulated in acute myeloid leukemia. The short isoforms compete with full-length SON for chromatin occupancy but lack the menin-binding ability, thereby antagonizing full-length SON function in transcriptional repression while not impairing full-length SON-mediated RNA splicing. Furthermore, overexpression of a short isoform of SON enhances replating potential of hematopoietic progenitors. Our findings define SON as a fine-tuner of the MLL-menin interaction and reveal short SON overexpression as a marker indicating aberrant transcriptional initiation in leukemia.


Assuntos
Proteínas de Ligação a DNA/genética , Histona-Lisina N-Metiltransferase/biossíntese , Leucemia Mieloide Aguda/genética , Proteína de Leucina Linfoide-Mieloide/biossíntese , Proteínas Proto-Oncogênicas/genética , Transcrição Gênica , Processamento Alternativo/genética , Linhagem Celular Tumoral , Cromatina/genética , Proteínas de Ligação a DNA/biossíntese , Regulação Leucêmica da Expressão Gênica , Histona-Lisina N-Metiltransferase/genética , Humanos , Leucemia Mieloide Aguda/patologia , Metilação , Antígenos de Histocompatibilidade Menor , Proteína de Leucina Linfoide-Mieloide/genética , Ligação Proteica , Isoformas de Proteínas/genética , Proteínas Proto-Oncogênicas/metabolismo
7.
Can Vet J ; 65(6): 553-558, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38827592

RESUMO

Gastrointestinal stromal tumors arising from gastric cardia are uncommon in dogs. A few studies have shown the effectiveness of tyrosine kinase inhibitors in the treatment of canine gastrointestinal stromal tumors, but no standardized protocols are currently available. An 11-year-old spayed female Maltese dog was diagnosed with a gastrointestinal stromal tumor using histopathological and immunohistochemical analyses. An adenosine triphosphate-based tumor chemosensitivity assay revealed that imatinib at lower concentrations had a stronger inhibitory effect than toceranib. Based on the results of the assay, the dog was treated with imatinib after surgery. After 28 mo of therapy, there was no recurrence of the tumor. Key clinical message: Adenosine triphosphate-based tumor chemosensitivity assays may help clinicians to select appropriate postoperative chemotherapeutic drugs for incompletely resected gastrointestinal stromal tumors in dogs.


Gestion réussie à la suite d'une résection incomplète d'une tumeur stromale gastro-intestinale à l'aide de l'imatinib basée sur un test de sensibilité tumorale à base d'adénosine triphosphate chez un chien. Les tumeurs stromales gastro-intestinales résultant du cardia gastrique sont rares chez le chien. Quelques études ont montré l'efficacité des inhibiteurs de la tyrosine kinase dans le traitement des tumeurs stromales gastrointestinales canines, mais aucun protocole standardisé n'est actuellement disponible. Une chienne maltaise stérilisée de 11 ans a reçu un diagnostic de tumeur stromale gastro-intestinale à l'aide d'analyses histopathologiques et immunohistochimiques. Un test de chimiosensibilité tumorale à base d'adénosine triphosphate a révélé que l'imatinib à des concentrations plus faibles avait un effet inhibiteur plus fort que le tocéranib. Sur la base des résultats du test, le chien a été traité avec de l'imatinib après l'opération. Après 28 mois de traitement, il n'y a eu aucune récidive de la tumeur.Message clinique clé :Les tests de chimiosensibilité tumorale à base d'adénosine triphosphate peuvent aider les cliniciens à sélectionner les médicaments chimiothérapeutiques postopératoires appropriés pour les tumeurs stromales gastro-intestinales incomplètement réséquées chez le chien.(Traduit par Dr Serge Messier).


Assuntos
Antineoplásicos , Doenças do Cão , Tumores do Estroma Gastrointestinal , Mesilato de Imatinib , Animais , Tumores do Estroma Gastrointestinal/veterinária , Tumores do Estroma Gastrointestinal/cirurgia , Tumores do Estroma Gastrointestinal/tratamento farmacológico , Tumores do Estroma Gastrointestinal/patologia , Cães , Mesilato de Imatinib/uso terapêutico , Doenças do Cão/tratamento farmacológico , Doenças do Cão/cirurgia , Feminino , Antineoplásicos/uso terapêutico , Trifosfato de Adenosina/uso terapêutico , Indóis , Pirróis
8.
Am J Epidemiol ; 192(8): 1358-1370, 2023 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-37070398

RESUMO

Little epidemiologic research has focused on pollution-related risks in medically vulnerable or marginalized groups. Using a nationwide 50% random sample of 2008-2016 Medicare Part D-eligible fee-for-service participants in the United States, we identified a cohort with high-risk conditions for cardiovascular and thromboembolic events (CTEs) and linked individuals with seasonal average zip-code-level concentrations of fine particulate matter (particulate matter with an aerodynamic diameter ≤ 2.5 µm (PM2.5)). We assessed the relationship between seasonal PM2.5 exposure and hospitalization for each of 7 CTE-related causes using history-adjusted marginal structural models with adjustment for individual demographic and neighborhood socioeconomic variables, as well as baseline comorbidity, health behaviors, and health-service measures. We examined effect modification across geographically and demographically defined subgroups. The cohort included 1,934,453 individuals with high-risk conditions (mean age = 77 years; 60% female, 87% White). A 1-µg/m3 increase in PM2.5 exposure was significantly associated with increased risk of 6 out of 7 types of CTE hospitalization. Strong increases were observed for transient ischemic attack (hazard ratio (HR) = 1.039, 95% confidence interval (CI): 1.034, 1.044), venous thromboembolism (HR = 1.031, 95% CI: 1.027, 1.035), and heart failure (HR = 1.019, 95% CI: 1.017, 1.020). Asian Americans were found to be particularly susceptible to thromboembolic effects of PM2.5 (venous thromboembolism: HR = 1.063, 95% CI: 1.021, 1.106), while Native Americans were most vulnerable to cerebrovascular effects (transient ischemic attack: HR = 1.093, 95% CI: 1.030, 1.161).


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Ataque Isquêmico Transitório , Tromboembolia Venosa , Humanos , Feminino , Idoso , Estados Unidos/epidemiologia , Masculino , Poluentes Atmosféricos/efeitos adversos , Poluentes Atmosféricos/análise , Ataque Isquêmico Transitório/induzido quimicamente , Medicare , Poluição do Ar/efeitos adversos , Poluição do Ar/análise , Material Particulado/efeitos adversos , Material Particulado/análise , Exposição Ambiental/efeitos adversos
9.
Circ Res ; 129(12): e215-e233, 2021 12 03.
Artigo em Inglês | MEDLINE | ID: mdl-34702049

RESUMO

RATIONALE: Vascular smooth muscle cells (SMCs) exhibit remarkable plasticity and can undergo dedifferentiation upon pathological stimuli associated with disease and interventions. OBJECTIVE: Although epigenetic changes are critical in SMC phenotype switching, a fundamental regulator that governs the epigenetic machineries regulating the fate of SMC phenotype has not been elucidated. METHODS AND RESULTS: Using SMCs, mouse models, and human atherosclerosis specimens, we found that FAK (focal adhesion kinase) activation elicits SMC dedifferentiation by stabilizing DNMT3A (DNA methyltransferase 3A). FAK in SMCs is activated in the cytoplasm upon serum stimulation in vitro or vessel injury and active FAK prevents DNMT3A from nuclear FAK-mediated degradation. However, pharmacological or genetic FAK catalytic inhibition forced FAK nuclear localization, which reduced DNMT3A protein via enhanced ubiquitination and proteasomal degradation. Reduced DNMT3A protein led to DNA hypomethylation in contractile gene promoters, which increased SMC contractile protein expression. RNA-sequencing identified SMC contractile genes as a foremost upregulated group by FAK inhibition from injured femoral artery samples compared with vehicle group. DNMT3A knockdown in injured arteries reduced DNA methylation and enhanced contractile gene expression supports the notion that nuclear FAK-mediated DNMT3A degradation via E3 ligase TRAF6 (TNF [tumor necrosis factor] receptor-associated factor 6) drives differentiation of SMCs. Furthermore, we observed that SMCs of human atherosclerotic lesions exhibited decreased nuclear FAK, which was associated with increased DNMT3A levels and decreased contractile gene expression. CONCLUSIONS: This study reveals that nuclear FAK induced by FAK catalytic inhibition specifically suppresses DNMT3A expression in injured vessels resulting in maintaining SMC differentiation by promoting the contractile gene expression. Thus, FAK inhibitors may provide a new treatment option to block SMC phenotypic switching during vascular remodeling and atherosclerosis.


Assuntos
Desdiferenciação Celular , Proteínas Contráteis/genética , Metilação de DNA , Quinase 1 de Adesão Focal/metabolismo , Músculo Liso Vascular/metabolismo , Miócitos de Músculo Liso/metabolismo , Animais , Células Cultivadas , Proteínas Contráteis/metabolismo , DNA Metiltransferase 3A/genética , DNA Metiltransferase 3A/metabolismo , Quinase 1 de Adesão Focal/genética , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Músculo Liso Vascular/citologia , Miócitos de Músculo Liso/citologia , Miócitos de Músculo Liso/fisiologia , Proteólise , Ubiquitinação , Regulação para Cima
10.
J Korean Med Sci ; 38(8): e56, 2023 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-36852852

RESUMO

BACKGROUND: Adverse drug reactions (ADRs) are escalating, and their socioeconomic burden is increasing. However, large-scale prospective studies investigating ADRs during hospitalization are rare in Korea. We prospectively investigated the incidence, characteristics, and economic burden of ADRs in hospitalized patients based on electronic medical records (EMRs). METHODS: Among patients admitted to three hospitals from October 2016 to October 2017, 5,000 patients were randomly selected and prospectively observed during hospitalization. Research nurses monitored and detected patients who had symptoms, signs, or laboratory findings suspicious for ADRs using an EMR-based detection protocol. Next, allergy and ADR specialists reviewed the medical records to determine the relationship between adverse reactions and drugs. Cases in which a causal relationship was certain, probable/likely, or possible were included in the ADR cases. Clinically meaningful ADR cases or those leading to prolonged hospitalization were defined as significant ADRs. RESULTS: ADRs occurred in 510 (10.2%) patients. The mean length of hospital stay was approximately 5 days longer in patients with ADRs. Opioids accounted for the highest percentage of total ADRs. Significant ADRs were observed in 148 (3.0%) patients. Antibiotics accounted for the highest percentage of significant ADRs. Drug hypersensitivity reactions (DHRs) occurred in 88 (1.8%) patients. Antibiotics accounted for the highest percentage of DHRs. The average medical expenses for one day of hospitalization per patient were highest in significant ADRs, followed by non-significant ADRs, and non-ADRs. CONCLUSION: ADRs in hospitalized patients are an important clinical issue, resulting in a substantial socioeconomic burden. EMR-based strategy could be a useful tool for ADR monitoring and early detection.


Assuntos
Hipersensibilidade a Drogas , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Humanos , Estudos Prospectivos , Estresse Financeiro , Incidência , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/epidemiologia , Hospitalização , Antibacterianos , Registros Eletrônicos de Saúde , República da Coreia/epidemiologia
11.
Can Vet J ; 64(5): 426-430, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37138720

RESUMO

Ammonia is a major neurotoxic substance associated with the complex pathogenesis of hepatic encephalopathy. Although several primary and secondary conditions have been reported to cause hyperammonemia, in veterinary medicine this condition is considered primarily associated with hepatic disease or portosystemic shunting. Only a few cases of inherited urea cycle enzyme deficiency and organic acid metabolic disorders have been reported in cats with hyperammonemia. To the best of our knowledge, this is the first report of hyperammonemia in a cat caused by accumulation of methylmalonic acid (MMA) secondary to functional cobalamin deficiency. A 2-year-old spayed female Turkish Angora cat exhibited postprandial depression with a 3-month history of hyperammonemia. Serum protein C and bile acid concentrations were normal. Plasma amino acid analysis revealed a deficiency of urea cycle amino acids. Although the serum cobalamin concentration was markedly high, there was no evidence of inflammatory, hepatic, or renal disease or neoplasia on blood, ultrasonographic, and computed tomographic examination. Gas chromatography-mass spectrometry revealed a high MMA concentration in the urine. Based on the results, functional cobalamin deficiency was diagnosed. Following oral amino acid supplementation and initiation of a low-protein diet, the serum ammonia level returned to normal and the postprandial depression improved. Urea cycle amino acid deficiency secondary to functional cobalamin deficiency presumably caused hyperammonemia due to MMA accumulation in this case.


Hyperammoniémie féline associée à un déficit fonctionnel en cobalamine : rapport de cas. L'ammoniac est une substance neurotoxique majeure associée à la pathogenèse complexe de l'encéphalopathie hépatique. Bien que plusieurs affections primaires et secondaires aient été signalées comme étant à l'origine d'une hyperammoniémie, en médecine vétérinaire, cette affection est considérée comme principalement associée à une maladie hépatique ou à un shunt porto-systémique. Seuls quelques cas de déficit héréditaire en enzymes du cycle de l'urée et de troubles métaboliques des acides organiques ont été signalés chez des chats atteints d'hyperammoniémie. À notre connaissance, il s'agit du premier rapport d'hyperammoniémie chez un chat causée par une accumulation d'acide méthylmalonique (MMA) secondaire à un déficit fonctionnel en cobalamine.Une chatte angora turque stérilisée âgée de 2 ans a présenté une dépression postprandiale avec une histoire d'hyperammoniémie depuis 3 mois. Les concentrations sériques de protéine C et d'acides biliaires étaient normales. L'analyse plasmatique des acides aminés a révélé une déficience en acides aminés du cycle de l'urée. Bien que la concentration sérique de cobalamine ait été nettement élevée, il n'y avait aucun signe de maladie inflammatoire, hépatique ou rénale ou de néoplasie à l'examen sanguin, échographique et tomodensitométrique. La chromatographie en phase gazeuse-spectrométrie de masse a révélé une forte concentration de MMA dans l'urine. Sur la base des résultats, un déficit fonctionnel en cobalamine a été diagnostiqué. Après une supplémentation orale en acides aminés et la mise en place d'un régime pauvre en protéines, le taux sérique d'ammoniac est revenu à la normale et la dépression postprandiale s'est améliorée. Une carence en acides aminés du cycle de l'urée secondaire à une carence en cobalamine fonctionnelle a vraisemblablement causé une hyperammoniémie due à l'accumulation de MMA dans ce cas.(Traduit par Dr Serge Messier).


Assuntos
Doenças do Gato , Hiperamonemia , Deficiência de Vitamina B 12 , Gatos , Animais , Feminino , Hiperamonemia/etiologia , Hiperamonemia/veterinária , Hiperamonemia/diagnóstico , Amônia , Deficiência de Vitamina B 12/complicações , Deficiência de Vitamina B 12/diagnóstico , Deficiência de Vitamina B 12/veterinária , Vitamina B 12/uso terapêutico , Ácido Metilmalônico/urina , Aminoácidos , Ureia , Doenças do Gato/diagnóstico , Doenças do Gato/etiologia
12.
Vet Med (Praha) ; 68(2): 83-89, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38332765

RESUMO

A 10-year-old spayed female Pomeranian dog was referred for hepatic mass evaluation. Blood tests revealed mildly elevated alkaline phosphatase activities. Computed tomography revealed a mass with multiple nodules on the right hepatic medial lobe adjacent to the caudal vena cava; histopathology confirmed mixed hepatocellular carcinoma (HCC) and cholangiocarcinoma (CC). Because of incomplete resection, adjuvant therapy was recommended. As tumour cells showed PDGFR-α, c-Kit, and FGFR1 overexpression, the anticancer effect of tyrosine kinase inhibitors was evaluated on the cells; toceranib was the most effective and was administered starting with an extra-labelled dose. The dog remained stable for 2.3 years with mild adverse effects. To our knowledge, this is the first successful clinical application of toceranib in a dog with mixed HCC-CC.

13.
Vet Med (Praha) ; 68(5): 225-230, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37982022

RESUMO

Osteosarcoma (OSA) is the most common malignant bone tumour in dogs; however, OSA of the maxilla is uncommon compared to appendicular OSA. Oral melanoma also commonly occurs in dogs with frequent distant metastasis. The role of adjuvant chemotherapy has been questioned in maxillary OSA and melanoma. A 17-year-old English Cocker Spaniel was referred with a growing mass on the right maxilla and a right lower lip mass. Osteosarcoma was diagnosed after partial maxillectomy, and the right lower lip mass was diagnosed as oral melanoma. Metronomic chemotherapy (MC) was performed, and the number of doses was tapered due to side effects at 5 weeks after initiation of MC. After 130 weeks of MC, chemotherapy was suspended due to kidney disease. After the suspension of chemotherapy, findings suggesting recurrence and metastasis were detected. The dog suddenly died 193 weeks after surgery, which was 8-14 times longer than the expected survival time. To the best of our knowledge, this is the first case report of successful long-term combination therapy, including surgery and MC, in a dog with maxillary OSA and lip melanoma. Our results show that the survival time can be greatly extended if MC is performed with proper management.

14.
Vet Med (Praha) ; 68(12): 477-482, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38303994

RESUMO

This case report follows a 10-year-old castrated male Miniature Schnauzer dog presented with a history of incomplete surgical resection of an oral malignant melanoma (amelanotic type) on the right mandible. Melanoma vaccine therapy was administered due to incomplete surgical resection, however, new masses were detected on the contralateral mandible and suspected pulmonary metastasis occurred at 2 weeks and 7 months, respectively, following the first melanoma vaccination. At the time of detecting the pulmonary metastasis, targeted chemotherapy was initiated with the owner's consent using imatinib (10 mg/kg/day, p.o.), a tyrosine kinase inhibitor (TKI). The patient did not show any significant adverse events related to both anticancer treatments. Three months following the first dose of imatinib, the absence of the suspected pulmonary metastatic nodules on radiography indicated complete remission. In conclusion, this report describes the achievement of clinical remission of suspected pulmonary metastatic oral malignant melanoma and an extension of survival time in a dog given a combination treatment of immunotherapy and tyrosine kinase inhibitor.

15.
Pharmacogenet Genomics ; 32(6): 226-234, 2022 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-35696287

RESUMO

BACKGROUND: Significant changes in CpG methylation have been identified in nasal polyps, which are the main targets of nonsteroidal anti-inflammatory drug-exacerbated respiratory disease (NERD); however, these polyps are composed of various cellular components. In the present study, whole-genome CpG methylation in peripheral blood lymphocytes (PBLs) was analyzed to define the epigenetic changes in lymphocytes, which are the primary immune cells involved in NERD. MATERIALS AND METHODS: Genomic DNA from peripheral blood mononuclear cells from 27 NERD and 24 aspirin-tolerant asthma (ATA) was subjected to bisulfate conversion and a methylation array. Quantitative CpG methylation, the ß-values as a quantitative measure of DNA methylation, in lymphocytes were calculated after adjustments for cellular composition. RESULTS: Fifty-six hypermethylated and three hypomethylated differentially methylated CpGs (DMCs) in PBLs in the NERD compared with ATA. The top 10 CpG loci predicted the methylation risk score, with a positive predictive value of 91.3%, a negative predictive value of 81.5% and an accuracy of 84.3%. As demonstrated in the nasal polyps, 30 DMCs were predicted to bind to the following 10 transcription factors, ranked in descending order: AP-2alphaA, TFII-1, STAT4, FOXP3, GR, c-Est-1, E2F-1, XBP1, ENKTF-1 and NF-1. Gene ontology analysis identified 13 categories such as regulation of T-helper 17 cell differentiation, including SMAD7 and NFKBIZ. PBLs in NERD contained no DMCs in genes associated with the prostaglandin and leukotriene pathways, which were found in ATA. CONCLUSION: PBLs in NERD form a unique pattern of DNA CpG methylation, and the combined analysis may provide predictive values for NERD.


Assuntos
Asma , Pólipos Nasais , Anti-Inflamatórios não Esteroides/efeitos adversos , Ilhas de CpG/genética , DNA/metabolismo , Metilação de DNA/genética , Humanos , Leucócitos Mononucleares , Linfócitos/metabolismo
16.
Respiration ; 101(5): 465-475, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34915526

RESUMO

BACKGROUND: Targeted therapies have broadened the available treatment options for patients with severe eosinophilic asthma (SEA). However, differences in the magnitude of treatment responses among patients indicate the presence of various underlying pathophysiological processes and patient subgroups. OBJECTIVES: We aimed to describe the characteristics of SEA and identify its patient subgroups. METHODS: Clinical data from the Cohort for Reality and Evolution of Adult Asthma in Korea were analyzed. Cluster analysis was performed among those with SEA using 5 variables, namely, prebronchodilator forced expiratory volume in 1 s, body mass index, age at symptom onset, smoking amount, and blood eosinophil counts. RESULTS: Patients with SEA showed prevalent sensitization to aeroallergens, decreased lung function, and poor asthma control status. Cluster analysis revealed 3 distinctive subgroups among patients with SEA. Cluster 1 (n = 177) consisted of patients reporting the lowest blood eosinophils (median, 346.8 cells/µL) and modest severe asthma with preserved lung function during the 12-month treatment period. Cluster 2 (n = 42) predominantly included smoking males with severe persistent airway obstruction and moderate eosinophilia (median, 451.8 cells/µL). Lastly, cluster 3 (n = 95) included patients with the most severe asthma, the highest eosinophil levels (median, 817.5 cells/µL), and good treatment response in terms of improved lung function and control status. CONCLUSIONS: Three subgroups were identified in SEA through the cluster analysis. The distinctive features of each cluster may help physicians predict patients who will respond to biologics with greater magnitude of clinical improvement. Further research regarding the underlying pathophysiology and clinical importance of each subgroup is warranted.


Assuntos
Asma , Eosinofilia Pulmonar , Adulto , Asma/complicações , Asma/diagnóstico , Asma/tratamento farmacológico , Eosinófilos , Volume Expiratório Forçado , Humanos , Contagem de Leucócitos , Masculino , Eosinofilia Pulmonar/tratamento farmacológico
17.
Int J Mol Sci ; 23(2)2022 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-35054777

RESUMO

Mycobacterium abscessus (M. abscessus) causes chronic pulmonary infections. Its resistance to current antimicrobial drugs makes it the most difficult non-tuberculous mycobacteria (NTM) to treat with a treatment success rate of 45.6%. Therefore, there is a need for new therapeutic agents against M. abscessus. We identified 10-DEBC hydrochloride (10-DEBC), a selective AKT inhibitor that exhibits inhibitory activity against M. abscessus. To evaluate the potential of 10-DEBC as a treatment for lung disease caused by M. abscessus, we measured its effectiveness in vitro. We established the intracellular activity of 10-DEBC against M. abscessus in human macrophages and human embryonic cell-derived macrophages (iMACs). 10-DEBC significantly inhibited the growth of wild-type M. abscessus and clinical isolates and clarithromycin (CLR)-resistant M. abscessus strains. 10-DEBC's drug efficacy did not have cytotoxicity in the infected macrophages. In addition, 10-DEBC operates under anaerobic conditions without replication as well as in the presence of biofilms. The alternative caseum binding assay is a unique tool for evaluating drug efficacy against slow and nonreplicating bacilli in their native caseum media. In the surrogate caseum, the mean undiluted fraction unbound (fu) for 10-DEBC is 5.696. The results of an in vitro study on the activity of M. abscessus suggest that 10-DEBC is a potential new drug for treating M. abscessus infections.


Assuntos
Antibacterianos , Macrófagos , Infecções por Mycobacterium não Tuberculosas , Mycobacterium abscessus , Proteínas Proto-Oncogênicas c-akt , Humanos , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Macrófagos/efeitos dos fármacos , Infecções por Mycobacterium não Tuberculosas/tratamento farmacológico , Oxazinas , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores
18.
Int J Mol Sci ; 23(16)2022 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-36012471

RESUMO

Alveolar organoids (AOs), derived from human pluripotent stem cells (hPSCs) exhibit lung-specific functions. Therefore, the application of AOs in pulmonary disease modeling is a promising tool for understanding disease pathogenesis. However, the lack of immune cells in organoids limits the use of human AOs as models of inflammatory diseases. In this study, we generated AOs containing a functional macrophage derived from hPSCs based on human fetal lung development using biomimetic strategies. We optimized culture conditions to maintain the iMACs (induced hPSC-derived macrophages) AOs for up to 14 days. In lipopolysaccharide (LPS)-induced inflammatory conditions, IL-1ß, MCP-1 and TNF-α levels were significantly increased in iMAC-AOs, which were not detected in AOs. In addition, chemotactic factor IL-8, which is produced by mononuclear phagocytic cells, was induced by LPS treatment in iMACs-AOs. iMACs-AOs can be used to understand pulmonary infectious diseases and is a useful tool in identifying the mechanism of action of therapeutic drugs in humans. Our study highlights the importance of immune cell presentation in AOs for modeling inflammatory pulmonary diseases.


Assuntos
Células-Tronco Pluripotentes Induzidas , Células-Tronco Pluripotentes , Diferenciação Celular , Humanos , Lipopolissacarídeos/farmacologia , Pulmão , Macrófagos , Organoides
19.
Molecules ; 27(2)2022 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-35056721

RESUMO

This research is conducted in order to investigate the structural and electrical characteristics of carbon nanowalls (CNWs) according to the sputtering time of interlayers. The thin films were deposited through RF magnetron sputtering with a 4-inch target (Ni and Ti) on the glass substrates, and the growth times of the deposition were 5, 10, and 30 min. Then, a microwave plasma-enhanced chemical vapor deposition (PECVD) system was used to grow CNWs on the interlayer-coated glass substrates by using a mixture of H2 and CH4 gases. The FE-SEM analysis of the cross-sectional and planar images confirmed that the thickness of interlayers linearly increased according to the deposition time. Furthermore, CNWs grown on the Ni interlayer were taller and denser than those grown on the Ti interlayer. Hall measurement applied to measure sheet resistance and conductivity confirmed that the electrical efficiency improved significantly as the Ni or Ti interlayers were used. Additionally, UV-Vis spectroscopy was also used to analyze the variations in light transmittance; CNWs synthesized on Ni-coated glass have lower average transmittance than those synthesized on Ti-coated glass. Based on this experiment, it was found that the direct growth of CNW was possible on the metal layer and the CNWs synthesized on Ni interlayers showed outstanding structural and electrical characterizations than the remaining interlayer type.

20.
Vet Med (Praha) ; 67(10): 544-551, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38716301

RESUMO

A 2-year-old, castrated, male Russian blue cat presented with acute dyspnoea, cyanosis, and lethargy. A thoracic radiography revealed a large cranial mediastinal mass; the computed tomography revealed caudal lobe atelectasis of the right lung with pericardial and pleural effusions. The cytodiagnostic tests revealed high-grade CD4+ CD8+ T-cell mediastinal lymphoma as clinical stage Vb; l-asparaginase-cyclophosphamide-doxorubicin-vincristine-prednisolone (l-CHOP)-based chemotherapy was initiated, following which the mass shrunk rapidly; 1 week after the initiation of chemotherapy, the appetite-related and respiratory symptoms improved dramatically, and the pleural and pericardial effusion resolved. The patient remains in complete remission three years after the initiation of the l-CHOP chemotherapy. Therefore, the accurate diagnosis and instantaneous initiation of chemotherapy may resolve life-threatening pleural and pericardial effusions in cats with high-grade aberrant T-cell mediastinal lymphoma.

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