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1.
J Imaging ; 10(6)2024 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-38921623

RESUMEN

Gloss is associated significantly with material appearance, and observers often focus on gloss unevenness. Gloss unevenness is the intensity distribution of reflected light observed within a highlight area, that is, the variability. However, it cannot be analyzed easily because it exists only within the highlight area and varies in appearance across the reflection angles. In recent years, gloss has been analyzed in terms of the intensity of specular reflection and its angular spread, or the bidirectional reflectance distribution function (BRDF). In this study, we develop an apparatus to measure gloss unevenness that can alter the angle with an angular resolution of 0.02°. Additionally, we analyze the gloss unevenness and BRDF in terms of specular reflection. Using a high angular resolution, we measure and analyze high-gloss materials, such as mirrors and plastics, and glossy materials, such as photo-like inkjet paper and coated paper. Our results show that the magnitude of gloss unevenness is the largest at angles marginally off the center of the specular reflection angle. We discuss an approach for physically defining gloss unevenness based on the BRDF.

2.
Bioorg Med Chem ; 108: 117775, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38851000

RESUMEN

4-[(5-[2-Methyl-5-(methylsulfonyl)pentan-2-yl]sulfonylpyrimidin-4-yl)amino]benzonitrile 2 was identified as a novel potent aldosterone synthase inhibitor. Compound 2 was found to inhibit human CYP11B2 in the nanomolar range, and showed an aldosterone-lowering effect in a furosemide-treated cynomolgus monkey model. Although human CYP11B2 has the high homology sequence with human CYP11B1, compound 2 showed more than 80 times higher selectivity over human CYP11B1 in vitro.


Asunto(s)
Citocromo P-450 CYP11B2 , Inhibidores Enzimáticos , Macaca fascicularis , Pirimidinas , Citocromo P-450 CYP11B2/antagonistas & inhibidores , Citocromo P-450 CYP11B2/metabolismo , Humanos , Animales , Pirimidinas/química , Pirimidinas/farmacología , Pirimidinas/síntesis química , Relación Estructura-Actividad , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/farmacología , Inhibidores Enzimáticos/síntesis química , Aldosterona/metabolismo , Aldosterona/química , Estructura Molecular
3.
Cell Metab ; 2024 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-38889724

RESUMEN

Deficiency of the epigenome modulator histone deacetylase 3 (HDAC3) in brown adipose tissue (BAT) impairs the ability of mice to survive in near-freezing temperatures. Here, we report that short-term exposure to mild cold temperature (STEMCT: 15°C for 24 h) averted lethal hypothermia of mice lacking HDAC3 in BAT (HDAC3 BAT KO) exposed to 4°C. STEMCT restored the induction of the thermogenic coactivator PGC-1α along with UCP1 at 22°C, which is greatly impaired in HDAC3-deficient BAT, and deletion of either UCP1 or PGC-1α prevented the protective effect of STEMCT. Remarkably, this protection lasted for up to 7 days. Transcriptional activator C/EBPß was induced by short-term cold exposure in mouse and human BAT and, uniquely, remained high for 7 days following STEMCT. Adeno-associated virus-mediated knockdown of BAT C/EBPß in HDAC3 BAT KO mice erased the persistent memory of STEMCT, revealing the existence of a C/EBPß-dependent and HDAC3-independent cold-adaptive epigenomic memory.

4.
Int Immunol ; 2024 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-38895753

RESUMEN

The generation and maintenance of memory T cells are regulated by various factors, including cytokines. Previous studies have shown that IL-27 is produced during the early acute phase of Plasmodium chabaudi chabaudi AS (Pcc) infection and inhibits the development of Th1-type memory CD4+ T cells. However, whether IL-27 acts directly on its receptor on Plasmodium-specific CD4+ T cells or indirectly via its receptor on other immune cells remains unclear. We aimed to determine the role of IL-27 receptor signaling in different immune cell types in regulating the generation and phenotype of memory CD4+ T cells during Plasmodium infection. We utilized Plasmodium-specific TCR transgenic mice, PbT-II, and Il27rα-/- mice to assess the direct and indirect effects of IL-27 signaling on memory CD4+ T-cell generation. Mice were transferred with PbT-II or Il27rα-/- PbT-II cells and infected with Pcc. Conditional knockout mice lacking the IL-27 receptor in T cells or dendritic cells were employed to discern the specific immune cell types involved in IL-27 receptor signaling. High levels of memory in PbT-II cells with Th1-shift occurred only when both PbT-II and host cells lacked the IL-27 receptor, suggesting the predominant inhibitory role of IL-27 signaling in both cell types. Furthermore, IL-27 receptor signaling in T cells limited the number of memory CD4+ T cells, while signaling in both T and dendritic cells contributed to the Th1 dominance of memory CD4+ T cells. These findings underscore the complex cytokine signaling network regulating memory CD4+ T cells during Plasmodium infection.

5.
Am J Sports Med ; 52(8): 2046-2054, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38819096

RESUMEN

BACKGROUND: Sacral fatigue fractures are a rare injury but should be considered as a differential diagnosis for low back and buttock pain in young adults. Collective reports are limited, most of which have focused on long-distance runners. PURPOSE: To investigate the characteristics of sacral fatigue fractures in adolescents. STUDY DESIGN: Case series; Level of evidence, 4. METHODS: We analyzed patient background characteristics, physical examination and imaging findings, and treatment courses of those diagnosed with sacral fatigue fractures using magnetic resonance imaging. RESULTS: Among 34 patients with sacral fatigue fractures, 15 and 19 were male and female patients, respectively, with an age range of 11 to 19 years (mean age, 15.0 years). Almost all patients were athletes, and 29 patients performed their sport ≥5 times a week. Long-distance runners were the most commonly affected, comprising 7 patients, and participants in other common sports such as baseball (6 patients), basketball (4 patients), and soccer (3 patients) were also affected. Physical examination revealed tension sign (Lasègue test) on the affected side in 6 patients and tight hamstrings in 24 patients. Imaging findings included 18 patients with right-side involvement, 12 with left-side involvement, and 4 with involvement on both sides. In 11 patients, spina bifida occulta was observed at S1 and 8 patients had a history of lumbar spondylolysis with 4 patients having concurrent sacral fatigue fractures. Physical therapy was performed concurrently with the cessation of exercise, and return to exercise was permitted if the pain had been relieved after 1 month. All patients returned to sports at a median of 48 days (range, 20-226 days) after symptom onset. However, 2 patients experienced recurrence (1 patient on the ipsilateral side and 1 patient on the contralateral side). CONCLUSION: Sacral stress fractures are not limited to long-distance runners in this population and can manifest as lower back pain or buttock pain in athletes participating in a variety of sports. Although the course of treatment was generally good, the possibility of recurrence must always be considered.


Asunto(s)
Traumatismos en Atletas , Fracturas por Estrés , Imagen por Resonancia Magnética , Sacro , Humanos , Femenino , Masculino , Adolescente , Sacro/lesiones , Sacro/diagnóstico por imagen , Fracturas por Estrés/terapia , Fracturas por Estrés/diagnóstico por imagen , Adulto Joven , Niño , Traumatismos en Atletas/terapia , Dolor de la Región Lumbar/terapia , Dolor de la Región Lumbar/etiología , Fracturas de la Columna Vertebral/terapia , Espina Bífida Oculta/complicaciones
6.
Nat Metab ; 6(5): 825-836, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38622413

RESUMEN

Nuclear receptor corepressors (NCoRs) function in multiprotein complexes containing histone deacetylase 3 (HDAC3) to alter transcriptional output primarily through repressive chromatin remodelling at target loci1-5. In the liver, loss of HDAC3 causes a marked hepatosteatosis largely because of de-repression of genes involved in lipid metabolism6,7; however, the individual roles and contribution of other complex members to hepatic and systemic metabolic regulation are unclear. Here we show that adult loss of both NCoR1 and NCoR2 (double knockout (KO)) in hepatocytes phenocopied the hepatomegalic fatty liver phenotype of HDAC3 KO. In addition, double KO livers exhibited a dramatic reduction in glycogen storage and gluconeogenic gene expression that was not observed with hepatic KO of individual NCoRs or HDAC3, resulting in profound fasting hypoglycaemia. This surprising HDAC3-independent activation function of NCoR1 and NCoR2 is due to an unexpected loss of chromatin accessibility on deletion of NCoRs that prevented glucocorticoid receptor binding and stimulatory effect on gluconeogenic genes. These studies reveal an unanticipated, non-canonical activation function of NCoRs that is required for metabolic health.


Asunto(s)
Gluconeogénesis , Histona Desacetilasas , Hígado , Ratones Noqueados , Co-Represor 1 de Receptor Nuclear , Co-Represor 2 de Receptor Nuclear , Receptores de Glucocorticoides , Gluconeogénesis/genética , Animales , Receptores de Glucocorticoides/metabolismo , Receptores de Glucocorticoides/genética , Co-Represor 1 de Receptor Nuclear/metabolismo , Co-Represor 1 de Receptor Nuclear/genética , Ratones , Histona Desacetilasas/metabolismo , Histona Desacetilasas/genética , Co-Represor 2 de Receptor Nuclear/metabolismo , Co-Represor 2 de Receptor Nuclear/genética , Hígado/metabolismo , Hepatocitos/metabolismo , Coactivador 2 del Receptor Nuclear/metabolismo , Coactivador 2 del Receptor Nuclear/genética
7.
iScience ; 27(4): 109398, 2024 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-38544573

RESUMEN

Mitochondria play a vital role in non-shivering thermogenesis in both brown and subcutaneous white adipose tissues (BAT and scWAT, respectively). However, specific regulatory mechanisms driving mitochondrial function in these tissues have been unclear. Here we demonstrate that prolonged activation of ß-adrenergic signaling induces epigenetic modifications in scWAT, specifically targeting the enhancers for the mitochondria master regulator genes Pgc1a/b. This is mediated at least partially through JMJD1A, a histone demethylase that in response to ß-adrenergic signals, facilitates H3K9 demethylation of the Pgc1a/b enhancers, promoting mitochondrial biogenesis and the formation of beige adipocytes. Disruption of demethylation activity of JMJD1A in mice impairs activation of Pgc1a/b driven mitochondrial biogenesis and limits scWAT beiging, contributing to reduced energy expenditure, obesity, insulin resistance, and metabolic disorders. Notably, JMJD1A demethylase activity is not required for Pgc1a/b dependent thermogenic capacity of BAT especially during acute cold stress, emphasizing the importance of scWAT thermogenesis in overall energy metabolism.

8.
J Intensive Care ; 11(1): 51, 2023 Nov 13.
Artículo en Inglés | MEDLINE | ID: mdl-37953283

RESUMEN

BACKGROUND: The aims of this study were to evaluate the efficacy, safety, and pharmacokinetics (PK) of continuous intravenous administration of remifentanil in mechanically ventilated patients in the intensive care unit (ICU). METHODS: This was a multicenter, randomized, double-blinded, fentanyl-controlled, non-inferiority phase 3 study. Patients aged ≥ 20 years requiring 6 h to 10 days mechanical ventilation in an ICU and requiring pain relief were randomly assigned in a 1:1 ratio to receive either remifentanil (n = 98) or fentanyl (n = 98). Dose was titrated from an infusion rate of 1 mL/h (remifentanil: 0.025 µg/kg/min, fentanyl: 0.1 µg/kg/h) until the target level of analgesia (behavioral pain scale [BPS] ≤ 5 or numerical rating score [NRS] ≤ 3) was achieved by escalating the dose in 1 mL/h increasing. Administration was then adjusted to maintain the target level of analgesia until weaning from the ventilator. The primary endpoint was the proportion of patients who did not require rescue fentanyl. Safety was assessed according to standard procedures. PK of remifentanil in the arterial blood was assessed in 24 patients. RESULTS: The proportion of patients achieving the primary endpoint in the remifentanil and fentanyl groups was 100% (92/92) and 97.8% (88/90), respectively. The difference between the groups was 2.2% (95% confidence interval, - 0.8-5.3) and non-inferiority of remifentanil to fentanyl was verified (p < 0.0001). The incidences of any adverse events in the remifentanil and fentanyl groups was 34 of 92 patients (37.0%) and 34 of 90 patients (37.8%), respectively. Adverse drug reactions was 12 in 92 patients (13.0%) and 15 in 90 patients (16.7%), respectively. In the PK analysis, blood remifentanil concentration decreased within 10 min to almost 50% of the end of administration, suggesting rapid offset of action following discontinuation of remifentanil. CONCLUSIONS: Remifentanil can be used safely for pain management in mechanically ventilated Japanese patients in the ICU. TRIAL REGISTRATION: Japan Registry of Clinical Trials, jRCT2080224954. Registered 20 November 2019, https://jrct.niph.go.jp/latest-detail/jRCT2080224954 .

9.
Artículo en Inglés | MEDLINE | ID: mdl-37807612

RESUMEN

STUDY DESIGN: Retrospective case series. OBJECTIVE: To report the detailed bone fusion rates and duration of treatment in unilateral and bilateral cases of pediatric lumbar spondylolysis (LS). SUMMARY OF BACKGROUND DATA: Early diagnosis and optimal conservative management for LS are crucial for achieving bony healing without surgery. However, existing research on the conservative treatment of pediatric LS, particularly regarding bone union rates and treatment duration for each stage of bilateral spondylolysis, is limited. METHODS: We retrospectively analyzed 590 pediatric patients (522 boys and 68 girls) under 18 years of age diagnosed with LS and treated conservatively from 2015 to 2021. Diagnosis was based on computed tomography scans and magnetic resonance imaging findings, with stages classified as very early, early, progressive, or terminal. Patient background, sports history, level and stage of spondylolysis, presence of spina bifida occulta, bone union rate, duration of conservative treatment, and recurrence rate were retrospectively analyzed. RESULTS: The overall bone union rate was 81.9%, with a mean conservative treatment duration of 53.7 days. Unilateral LS cases showed decreased bone union rates with stage advancement (very early; 98.2%, early; 96.0%, progressive; 64.3%). Bilateral LS cases with progressive or terminal stage demonstrated low bone union rates (very early/very early; 100%, early/very early; 94.1%, progressive/very early; 66.7%, early/early; 82.9%, progressive/early; 32.3%, progressive/progressive; 23.7%, very early/terminal; 0%, early/terminal; 50.0%, progressive/terminal; 11.1%). The duration of conservative treatment extended as the stage of the main and contralateral lesions progressed, ranging from 39.1 days (very early/none) to 105 days (progressive/terminal). Recurrence rate after bone fusion was 16.6%, with no differences based on lesion stage. CONCLUSION: In this series of 590 patients, conservative treatment yielded high bone union rates for pediatric LS. However, union rates decreased with stage advancement, especially in bilateral cases. These findings provide valuable insights for prognosticating natural history and outcome regarding LS treatment, bone union and return to activity.

10.
EMBO Mol Med ; 15(12): e17713, 2023 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-37855243

RESUMEN

Malaria infection elicits both protective and pathogenic immune responses, and IL-27 is a critical cytokine that regulate effector responses during infection. Here, we identified a critical window of CD4+ T cell responses that is targeted by IL-27. Neutralization of IL-27 during acute infection with Plasmodium chabaudi expanded specific CD4+ T cells, which were maintained at high levels thereafter. In the chronic phase, Plasmodium-specific CD4+ T cells in IL-27-neutralized mice consisted mainly of CD127+ KLRG1- and CD127- KLRG1+ subpopulations that displayed distinct cytokine production, proliferative capacity, and are maintained in a manner independent of active infection. Single-cell RNA-seq analysis revealed that these CD4+ T cell subsets formed independent clusters that express unique Th1-type genes. These IL-27-neutralized mice exhibited enhanced cellular and humoral immune responses and protection. These findings demonstrate that IL-27, which is produced during the acute phase of malaria infection, inhibits the development of unique Th1 memory precursor CD4+ T cells, suggesting potential implications for the development of vaccines and other strategic interventions.


Asunto(s)
Interleucina-27 , Malaria , Plasmodium chabaudi , Ratones , Animales , Linfocitos T , Malaria/patología , Linfocitos T CD4-Positivos , Ratones Endogámicos C57BL
11.
Asian Spine J ; 17(4): 750-760, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37408293

RESUMEN

STUDY DESIGN: A single-center retrospective study. PURPOSE: To research the predictive factors associated with postoperative patient satisfaction 1 year after minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF), a minimally invasive procedure for lumbar degenerative disease. OVERVIEW OF LITERATURE: There have been reports of numerous variables influencing patient satisfaction with lumbar surgery; however, there have been few investigations on MIS are limited. METHODS: This study included 229 patients (107 men and 122 women; mean age, 68.9 years) who received one or two levels of MISTLIF, and the patient's age, gender, disease, paralysis, preoperative physical functions, duration of symptom(s), and surgery-associated factors (waiting for surgery, number of surgical levels, surgical time, and intraoperative blood loss) were studied. Radiographic characteristics and clinical outcomes such as Oswestry Disability Index (ODI) scores and Visual Analog Scale (VAS; 0-100) ODI scores for low back pain, leg pain, and numbness were studied. One year following surgery, patient satisfaction (defined as satisfaction for surgery and for present condition; 0-100) was assessed using VAS and its relationships with investigation factors were examined. RESULTS: The mean VAS scores of satisfaction for surgery and for present condition were 88.6 and 84.2, respectively. The results of multiple regression analysis showed that preoperative adverse factors of satisfaction for surgery were being elderly (ß =-0.17, p =0.023), high preoperative low back pain VAS scores (ß =-0.15, p =0.020), and postoperative adverse factors were high postoperative ODI scores (ß =-0.43, p <0.001). In addition, the preoperative adverse factor of satisfaction for present condition was high preoperative low back pain VAS scores (ß =-0.21, p =0.002), and postoperative adverse factors were high postoperative ODI scores (ß =-0.45, p <0.001) and high postoperative low back pain VAS scores (ß =-0.26, p =0.001). CONCLUSIONS: According to this study, significant preoperative low back pain and high postoperative ODI score after surgery are linked to patient unhappiness.

12.
ACS Infect Dis ; 9(7): 1303-1309, 2023 07 14.
Artículo en Inglés | MEDLINE | ID: mdl-37321567

RESUMEN

Artemisinins have been used as first-line drugs worldwide to treat malaria caused by Plasmodium falciparum; however, its underlying mechanism is still unclear. This study aimed to identify the factors inducing growth inhibition via pyknosis, a state of intraerythrocytic developmental arrest, when exposing the parasite to dihydroartemisinin (DHA). Changes in the expression of genome-wide transcripts were assessed in the parasites treated with antimalarials, revealing the specific downregulation of zinc-associated proteins by DHA. The quantification of zinc levels in DHA-treated parasite indicated abnormal zinc depletion. Notably, the zinc-depleted condition in the parasite produced by a zinc chelator induced the generation of a pyknotic form and the suppression of its proliferation. The evaluation of the antimalarial activity of DHA or a glutathione-synthesis inhibitor in the zinc-depleted state showed that the disruption of zinc and glutathione homeostasis synergistically potentiated the growth inhibition of P. falciparum through pyknosis. These findings could help further understand the antimalarial actions of artemisinins for advancing malaria therapy.


Asunto(s)
Antimaláricos , Artemisininas , Antagonistas del Ácido Fólico , Malaria Falciparum , Malaria , Parásitos , Animales , Humanos , Antimaláricos/farmacología , Plasmodium falciparum , Artemisininas/farmacología , Malaria Falciparum/tratamiento farmacológico , Malaria/tratamiento farmacológico , Homeostasis , Glutatión
13.
Microbiol Immunol ; 67(5): 239-247, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36829293

RESUMEN

Malaria is one of the deadliest infectious diseases. Licensed vaccine have demonstrated just over 30% efficacy, and therefore, developing new vaccine candidates and understanding immune responses to Plasmodium have become necessary. γδ T cells have been suggested to be associated with immune responses to malaria due to the observation of their expansion in patients with malaria and experimental models of malaria. γδ T cells act as both "innate-like" and "adaptive-like" cells during immune response to malaria. Studies have found that γδ T cells can recognize Plasmodium phosphoantigen, present the antigen, and initiate adaptive immune response during blood-stage Plasmodium infection. Recent reports also suggested the phagocytic and cytotoxic potential of γδ T cells. Furthermore, γδ T cells can provide protection upon immunization with whole parasite. In addition, γδ T cells during the liver-stage infection were able to prevent experimental cerebral malaria. Despite these new findings, questions related to γδ T-cell response during Plasmodium infection remain to be answered. However, investigating these cells in humans remains difficult in many ways; in this regard, rodent models of malarial infection enable us to study these cells in more detail. Insights from experimental malaria models give rise to new cues for development of malarial vaccine and adjunctive therapy for severe malaria. Here, we review our current knowledge of γδ T-cell immune function in human and experimental mouse malarial infection models; especially, we focus on the mechanisms underlying γδ T cells that are associated with protective immunity during malarial infection.


Asunto(s)
Malaria , Linfocitos T , Humanos , Animales , Ratones , Receptores de Antígenos de Linfocitos T gamma-delta , Malaria/prevención & control , Inmunidad
14.
Parasitol Int ; 92: 102646, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35998816

RESUMEN

Malaria is a life-threatening disease caused by infection with Plasmodium parasites. The goal of developing an effective malaria vaccine is yet to be reached despite decades of massive research efforts. CD4+ helper T cells, CD8+ cytotoxic T cells, and γδ T cells are associated with immune responses to both liver-stage and blood-stage Plasmodium infection. The immune responses of T cell-lineages to Plasmodium infection are associated with both protection and immunopathology. Studies with mouse model of malaria contribute to our understanding of host immune response. In this paper, we focus primarily on mouse malaria model with blood-stage Plasmodium berghei infection and review our knowledge of T cell immune responses against Plasmodium infection. Moreover, we also discuss findings of experimental human studies. Uncovering the precise mechanisms of T cell-mediated immunity to Plasmodium infection can be accomplished through further investigations using mouse models of malaria with rodent Plasmodium parasites. Those findings would be invaluable to advance the efforts for development of an effective malaria vaccine.


Asunto(s)
Vacunas contra la Malaria , Malaria , Humanos , Animales , Ratones , Plasmodium berghei , Linfocitos T , Inmunidad Celular , Modelos Animales de Enfermedad
15.
Drug Metab Dispos ; 51(1): 67-80, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36273823

RESUMEN

In a previous study on the human mass balance of DS-1971a, a selective NaV1.7 inhibitor, its CYP2C8-dependent metabolite M1 was identified as a human disproportionate metabolite. The present study assessed the usefulness of pharmacokinetic evaluation in chimeric mice grafted with human hepatocytes (PXB-mice) and physiologically based pharmacokinetic (PBPK) simulation of M1. After oral administration of radiolabeled DS-1971a, the most abundant metabolite in the plasma, urine, and feces of PXB-mice was M1, while those of control SCID mice were aldehyde oxidase-related metabolites including M4, suggesting a drastic difference in the metabolism between these mouse strains. From a qualitative perspective, the metabolite profile observed in PXB-mice was remarkably similar to that in humans, but the quantitative evaluation indicated that the area under the plasma concentration-time curve (AUC) ratio of M1 to DS-1971a (M1/P ratio) was approximately only half of that in humans. A PXB-mouse-derived PBPK model was then constructed to achieve a more accurate prediction, giving an M1/P ratio (1.3) closer to that in humans (1.6) than the observed value in PXB-mice (0.69). In addition, simulated maximum plasma concentration and AUC values of M1 (3429 ng/ml and 17,116 ng·h/ml, respectively) were similar to those in humans (3180 ng/ml and 18,400 ng·h/ml, respectively). These results suggest that PBPK modeling incorporating pharmacokinetic parameters obtained with PXB-mice is useful for quantitatively predicting exposure to human disproportionate metabolites. SIGNIFICANCE STATEMENT: The quantitative prediction of human disproportionate metabolites remains challenging. This paper reports on a successful case study on the practical estimation of exposure (C max and AUC) to DS-1971a and its CYP2C8-dependent, human disproportionate metabolite M1, by PBPK simulation utilizing pharmacokinetic parameters obtained from PXB-mice and in vitro kinetics in human liver fractions. This work adds to the growing knowledge regarding metabolite exposure estimation by static and dynamic models.


Asunto(s)
Aldehído Oxidasa , Hígado , Humanos , Ratones , Animales , Aldehído Oxidasa/metabolismo , Citocromo P-450 CYP2C8/metabolismo , Ratones SCID , Hígado/metabolismo , Sistema Enzimático del Citocromo P-450/metabolismo , Modelos Biológicos
16.
Biochem Biophys Res Commun ; 637: 58-65, 2022 12 31.
Artículo en Inglés | MEDLINE | ID: mdl-36375251

RESUMEN

Malaria is an infectious disease caused by Plasmodium parasites and has high mortality rates, especially among children in African and Southeast Asian countries. Patients with hemolytic anemia are suggested to adapt protective measures against malarial infection. Nicotinamide adenine dinucleotide (NAD+) is a crucial cofactor associated with numerous biological processes that maintain homeostasis in all living organisms. In a previous study, we had demonstrated that the deficiency of nicotinamide mononucleotide adenylyltransferase 3 (Nmnat3), an enzyme catalyzing NAD+ synthesis, causes hemolytic anemia accompanied by a drastic decline in the NAD+ levels in the erythrocytes. It is well known that hemolytic anemia is linked to a reduced risk of malarial infections. In the present study, we investigated whether hemolytic anemia caused by Nmnat3 deficiency is beneficial against malarial infections. We found that Nmnat3 deficiency exacerbated malarial infection and subsequently caused death. Moreover, we demonstrated that the NAD+ levels in malaria-infected Nmnat3 red blood cells significantly increased and the glycolytic flow was largely enhanced to support the rapid growth of malarial parasites. Our results revealed that hemolytic anemia induced by the deletion of Nmnat3 was harmful rather than protective against malaria.


Asunto(s)
Anemia Hemolítica , Malaria , Nicotinamida-Nucleótido Adenililtransferasa , Niño , Humanos , Anemia Hemolítica/complicaciones , Anemia Hemolítica/genética , Eritrocitos/metabolismo , Malaria/complicaciones , NAD/metabolismo , Nicotinamida-Nucleótido Adenililtransferasa/genética , Nicotinamida-Nucleótido Adenililtransferasa/metabolismo , Animales
17.
J Opt Soc Am A Opt Image Sci Vis ; 39(6): B28-B38, 2022 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-36215525

RESUMEN

This study examines the human gloss perception of printing papers at various illuminances and distances from a light source to the object's surface. Gloss is evaluated based on not only the intensity of reflected light but also the sharpness of specular highlights. The apparent spread of the reflected light source image, which is also used for gloss evaluations, depends on the distance between the light source and the object's surface. Unlike physical variation of specular image properties, the perception of gloss may exhibit constancy similar to color perception. Our results reveal that illuminance has a strong effect on gloss perception. We found cases where low-gloss samples looked glossier than high-gloss ones-the gloss reversal phenomenon. These results suggest that there is a case in which gloss constancy may not work in every condition.


Asunto(s)
Percepción de Forma , Sensibilidad de Contraste , Humanos , Propiedades de Superficie
18.
Proc Natl Acad Sci U S A ; 119(33): e2205276119, 2022 08 16.
Artículo en Inglés | MEDLINE | ID: mdl-35939699

RESUMEN

Brown adipose tissue (BAT) is a key thermogenic organ whose expression of uncoupling protein 1 (UCP1) and ability to maintain body temperature in response to acute cold exposure require histone deacetylase 3 (HDAC3). HDAC3 exists in tight association with nuclear receptor corepressors (NCoRs) NCoR1 and NCoR2 (also known as silencing mediator of retinoid and thyroid receptors [SMRT]), but the functions of NCoR1/2 in BAT have not been established. Here we report that as expected, genetic loss of NCoR1/2 in BAT (NCoR1/2 BAT-dKO) leads to loss of HDAC3 activity. In addition, HDAC3 is no longer bound at its physiological genomic sites in the absence of NCoR1/2, leading to a shared deregulation of BAT lipid metabolism between NCoR1/2 BAT-dKO and HDAC3 BAT-KO mice. Despite these commonalities, loss of NCoR1/2 in BAT does not phenocopy the cold sensitivity observed in HDAC3 BAT-KO, nor does loss of either corepressor alone. Instead, BAT lacking NCoR1/2 is inflamed, particularly with respect to the interleukin-17 axis that increases thermogenic capacity by enhancing innervation. Integration of BAT RNA sequencing and chromatin immunoprecipitation sequencing data revealed that NCoR1/2 directly regulate Mmp9, which integrates extracellular matrix remodeling and inflammation. These findings reveal pleiotropic functions of the NCoR/HDAC3 corepressor complex in BAT, such that HDAC3-independent suppression of BAT inflammation counterbalances stimulation of HDAC3 activity in the control of thermogenesis.


Asunto(s)
Tejido Adiposo Pardo , Co-Represor 1 de Receptor Nuclear , Co-Represor 2 de Receptor Nuclear , Termogénesis , Tejido Adiposo Pardo/metabolismo , Animales , Histona Desacetilasas/metabolismo , Inflamación/metabolismo , Ratones , Ratones Noqueados , Co-Represor 1 de Receptor Nuclear/genética , Co-Represor 1 de Receptor Nuclear/metabolismo , Co-Represor 2 de Receptor Nuclear/genética , Co-Represor 2 de Receptor Nuclear/metabolismo , Receptores de Ácido Retinoico/metabolismo , Termogénesis/genética , Proteína Desacopladora 1/genética , Proteína Desacopladora 1/metabolismo
19.
Int Immunol ; 34(1): 21-33, 2022 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-34648636

RESUMEN

Plasmodium parasites that infect humans are highly polymorphic, and induce various infections ranging from an asymptomatic state to life-threatening diseases. However, how the differences between the parasites affect host immune responses during blood-stage infection remains largely unknown. We investigated the CD4+ T-cell immune responses in mice infected with P. berghei ANKA (PbA) or P. chabaudi chabaudi AS (Pcc) using PbT-II cells, which recognize a common epitope of these parasites. In the acute phase of infection, CD4+ T-cell responses in PbA-infected mice showed a lower involvement of Th1 cells and a lower proportion of Ly6Clo effector CD4+ T cells than those in Pcc-infected mice. Transcriptome analysis of PbT-II cells indicated that type I interferon (IFN)-regulated genes were expressed at higher levels in both Th1- and Tfh-type PbT-II cells from PbA-infected mice than those from Pcc-infected mice. Moreover, IFN-α levels were considerably higher in PbA-infected mice than in Pcc-infected mice. Inhibition of type I IFN signaling increased PbT-II and partially reversed the Th1 over Tfh bias of the PbT-II cells in both PbA- and Pcc-infected mice. In the memory phase, PbT-II cells in PbA-primed mice maintained higher numbers and exhibited a better recall response to the antigen. However, recall responses were not significantly different between the infection groups after re-challenge with PbA, suggesting the effect of the inflammatory environment by the infection. These observations suggest that the differences in Plasmodium-specific CD4+ T-cell responses between PbA- and Pcc-infected mice were associated with the difference in type I IFN production during the early phase of the infection.


Asunto(s)
Linfocitos T CD4-Positivos/inmunología , Interferón Tipo I/biosíntesis , Malaria/inmunología , Plasmodium berghei/inmunología , Plasmodium chabaudi/inmunología , Animales , Células Cultivadas , Ratones , Ratones Transgénicos
20.
Drug Metab Dispos ; 50(3): 235-242, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-34930785

RESUMEN

Predicting human disproportionate metabolites is difficult, especially when drugs undergo species-specific metabolism mediated by cytochrome P450s (P450s) and/or non-P450 enzymes. This study assessed human metabolites of DS-1971a, a potent Nav1.7-selective blocker, by performing human mass balance studies and characterizing DS-1971a metabolites, in accordance with the Metabolites in Safety Testing guidance. In addition, we investigated the mechanism by which the major human disproportionate metabolite (M1) was formed. After oral administration of radiolabeled DS-1971a, the major metabolites in human plasma were P450-mediated monoxidized metabolites M1 and M2 with area under the curve ratios of 27% and 10% of total drug-related exposure, respectively; the minor metabolites were dioxidized metabolites produced by aldehyde oxidase and P450s. By comparing exposure levels of M1 and M2 between humans and safety assessment animals, M1 but not M2 was found to be a human disproportionate metabolite, requiring further characterization under the Metabolites in Safety Testing guidance. Incubation studies with human liver microsomes indicated that CYP2C8 was responsible for the formation of M1. Docking simulation indicated that, in the formation of M1 and M2, there would be hydrogen bonding and/or electrostatic interactions between the pyrimidine and sulfonamide moieties of DS-1971a and amino acid residues Ser100, Ile102, Ile106, Thr107, and Asn217 in CYP2C8, and that the cyclohexane ring of DS-1971a would be located near the heme iron of CYP2C8. These results clearly indicate that M1 is the predominant metabolite in humans and a human disproportionate metabolite due to species-specific differences in metabolism. SIGNIFICANCE STATEMENT: This report is the first to show a human disproportionate metabolite generated by CYP2C8-mediated primary metabolism. We clearly demonstrate that DS-1971a, a mixed aldehyde oxidase and cytochrome P450 substrate, was predominantly metabolized by CYP2C8 to form M1, a human disproportionate metabolite. Species differences in the formation of M1 highlight the regio- and stereoselective metabolism by CYP2C8, and the proposed interaction between DS-1971a and CYP2C8 provides new knowledge of CYP2C8-mediated metabolism of cyclohexane-containing substrates.


Asunto(s)
Aldehído Oxidasa , Sulfonamidas , Aldehído Oxidasa/metabolismo , Animales , Citocromo P-450 CYP2C8/metabolismo , Sistema Enzimático del Citocromo P-450/metabolismo , Humanos , Microsomas Hepáticos/metabolismo , Pirazoles , Pirimidinas/metabolismo , Sulfonamidas/metabolismo
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