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1.
Anal Chem ; 96(1): 170-178, 2024 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-38155534

RESUMEN

Characterization of the elemental distribution of samples with rough surfaces has been strongly desired for the analysis of various natural and artificial materials. Particularly for pristine and rare analytes with micrometer sizes embedded on specimen surfaces, non-invasive and matrix effect-free analysis is required without surface polishing treatment. To satisfy these requirements, we proposed a new method employing the sequential combination of two imaging modalities, i.e., microenergy-dispersive X-ray fluorescence (micro-XRF) and Raman micro-spectroscopy. The applicability of the developed method is tested by the quantitative analysis of cation composition in micrometer-sized carbonate grains on the surfaces of intact particles sampled directly from the asteroid Ryugu. The first step of micro-XRF imaging enabled a quick search for the sparsely scattered and micrometer-sized carbonates by the codistributions of Ca2+ and Mn2+ on the Mg2+- and Fe2+-rich phyllosilicate matrix. The following step of Raman micro-spectroscopy probed the carbonate grains and analyzed their cation composition (Ca2+, Mg2+, and Fe2+ + Mn2+) in a matrix effect-free manner via the systematic Raman shifts of the lattice modes. The carbonates were basically assigned to ferroan dolomite bearing a considerable amount of Fe2+ + Mn2+ at around 10 atom %. These results are in good accordance with the assignments reported by scanning electron microscopy-energy-dispersive X-ray spectroscopy, where the thin-sectioned and surface-polished Ryugu particles were applicable. The proposed method requires neither sectioning nor surface polishing; hence, it can be applied to the remote sensing apparatus on spacecrafts and planetary rovers. Furthermore, the non-invasive and matrix effect-free characterization will provide a reliable analytical tool for quantitative analysis of the elemental distribution on the samples with surface roughness and chemical heterogeneity at a micrometer scale, such as art paintings, traditional crafts with decorated shapes, as well as sands and rocks with complex morphologies in nature.

2.
Am J Physiol Gastrointest Liver Physiol ; 323(6): G571-G585, 2022 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-36194131

RESUMEN

Colorectal cancer (CRC) is a leading cause of cancer-related death. There is an urgent need for new methods of early CRC detection and monitoring to improve patient outcomes. Extracellular vesicles (EVs) are secreted, lipid-bilayer bound, nanoparticles that carry biological cargo throughout the body and in turn exhibit cancer-related biomarker potential. RNA binding proteins (RBPs) are posttranscriptional regulators of gene expression that may provide a link between host cell gene expression and EV phenotypes. Insulin-like growth factor 2 RNA binding protein 1 (IGF2BP1/IMP1) is an RBP that is highly expressed in CRC with higher levels of expression correlating with poor prognosis. IMP1 binds and potently regulates tumor-associated transcripts that may impact CRC EV phenotypes. Our objective was to test whether IMP1 expression levels impact EV secretion and/or cargo. We used RNA sequencing, in vitro CRC cell lines, ex vivo colonoid models, and xenograft mice to test the hypothesis that IMP1 influences EV secretion and/or cargo in human CRC. Our data demonstrate that IMP1 modulates the RNA expression of transcripts associated with extracellular vesicle pathway regulation, but it has no effect on EV secretion levels in vitro or in vivo. Rather, IMP1 appears to affect EV regulation by directly entering EVs in a transformation-dependent manner. These findings suggest that IMP1 has the ability to shape EV cargo in human CRC, which could serve as a diagnostic/prognostic circulating tumor biomarker.NEW & NOTEWORTHY This work demonstrates that the RNA binding protein IGF2BP1/IMP1 alters the transcript profile of colorectal cancer cell (CRC) mRNAs from extracellular vesicle (EV) pathways. IMP1 does not alter EV production or secretion in vitro or in vivo, but rather enters CRC cells where it may further impact EV cargo. Our work shows that IMP1 has the ability to shape EV cargo in human CRC, which could serve as a diagnostic/prognostic circulating tumor biomarker.


Asunto(s)
Neoplasias Colorrectales , Vesículas Extracelulares , Humanos , Ratones , Animales , Vesículas Extracelulares/metabolismo , Proteínas de Unión al ARN/genética , Proteínas de Unión al ARN/metabolismo , ARN Mensajero/genética , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Neoplasias Colorrectales/patología
3.
Biol Reprod ; 104(4): 924-934, 2021 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-33459759

RESUMEN

Abnormally increased angiotensin II activity related to maternal angiotensinogen (AGT) genetic variants, or aberrant receptor activation, is associated with small-for-gestational-age babies and abnormal uterine spiral artery remodeling in humans. Our group studies a murine AGT gene titration transgenic (TG; 3-copies of the AGT gene) model, which has a 20% increase in AGT expression mimicking a common human AGT genetic variant (A[-6]G) associated with intrauterine growth restriction (IUGR) and spiral artery pathology. We hypothesized that aberrant maternal AGT expression impacts pregnancy-induced uterine spiral artery angiogenesis in this mouse model leading to IUGR. We controlled for fetal sex and fetal genotype (e.g., only 2-copy wild-type [WT] progeny from WT and TG dams were included). Uteroplacental samples from WT and TG dams from early (days 6.5 and 8.5), mid (d12.5), and late (d16.5) gestation were studied to assess uterine natural killer (uNK) cell phenotypes, decidual metrial triangle angiogenic factors, placental growth and capillary density, placental transcriptomics, and placental nutrient transport. Spiral artery architecture was evaluated at day 16.5 by contrast-perfused three-dimensional microcomputed tomography (3D microCT). Our results suggest that uteroplacental angiogenesis is significantly reduced in TG dams at day 16.5. Males from TG dams are associated with significantly reduced uteroplacental angiogenesis from early to late gestation compared with their female littermates and WT controls. Angiogenesis was not different between fetal sexes from WT dams. We conclude that male fetal sex compounds the pathologic impact of maternal genotype in this mouse model of growth restriction.


Asunto(s)
Retardo del Crecimiento Fetal/fisiopatología , Feto/fisiología , Neovascularización Patológica , Placenta/irrigación sanguínea , Animales , Modelos Animales de Enfermedad , Femenino , Desarrollo Fetal/fisiología , Retardo del Crecimiento Fetal/inmunología , Retardo del Crecimiento Fetal/patología , Células Asesinas Naturales/patología , Masculino , Ratones , Ratones Endogámicos C57BL , Neovascularización Patológica/etiología , Neovascularización Patológica/inmunología , Neovascularización Patológica/fisiopatología , Placenta/inmunología , Placenta/patología , Placentación/fisiología , Embarazo , Caracteres Sexuales , Diferenciación Sexual/fisiología , Útero/irrigación sanguínea , Útero/inmunología , Útero/patología
4.
J Bone Miner Metab ; 36(6): 679-690, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-29273889

RESUMEN

Osteoclasts and foreign body giant cells (FBGCs) are derived from common progenitors and share properties such as multi-nucleation capacity induced by cell-cell fusion; however, mechanisms underlying lineage determination between these cells remain unclear. Here we show that, under inflammatory conditions, osteoclasts are stimulated in a manner similar to M1 macrophages, while formation of FBGCs, which exhibit M2-like phenotypes, is inhibited in a manner similar to that seen in M1/M2 macrophage polarization. FBGC/osteoclast polarization was inhibited by conditional knockout of tumor necrosis factor receptor associated factor 6 (Traf6) in adults in vivo and in vitro. Traf6-null mice were previously reported to die soon after birth, but we found that Traf6 deletion in adults did not cause lethality but rather inhibited osteoclast activation and prevented FBGC inhibition under inflammatory conditions. Accordingly, basal osteoclastogenesis was significantly inhibited by Traf6 deletion in vivo and in vitro and accompanied by increased bone mass. Lipopolysaccharide-induced osteoclast formation and osteolysis were significantly inhibited in Traf6 conditional knockout mice. Our results suggest that Traf6 plays a crucial role in regulating M1 osteoclast and M2 FBGC polarization and is a potential therapeutic target in blocking FBGC inhibition, antagonizing osteolysis in inflammatory conditions, and increasing bone mass without adverse effects in adults.


Asunto(s)
Células Gigantes de Cuerpo Extraño/metabolismo , Células Gigantes de Cuerpo Extraño/patología , Inflamación/patología , Osteoclastos/metabolismo , Factor 6 Asociado a Receptor de TNF/metabolismo , Animales , Diferenciación Celular , Femenino , Interleucina-1beta/metabolismo , Lipopolisacáridos , Masculino , Ratones Noqueados , Osteoclastos/patología , Osteólisis/metabolismo , Osteólisis/patología , Choque Séptico/metabolismo , Choque Séptico/patología
5.
J Biol Chem ; 291(23): 12184-94, 2016 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-27129272

RESUMEN

Skeletal muscle atrophy promotes muscle weakness, limiting activities of daily living. However, mechanisms underlying atrophy remain unclear. Here, we show that skeletal muscle immobilization elevates Smad2/3 protein but not mRNA levels in muscle, promoting atrophy. Furthermore, we demonstrate that myostatin, which negatively regulates muscle hypertrophy, is dispensable for denervation-induced muscle atrophy and Smad2/3 protein accumulation. Moreover, muscle-specific Smad2/3-deficient mice exhibited significant resistance to denervation-induced muscle atrophy. In addition, expression of the atrogenes Atrogin-1 and MuRF1, which underlie muscle atrophy, did not increase in muscles of Smad2/3-deficient mice following denervation. We also demonstrate that serum starvation promotes Smad2/3 protein accumulation in C2C12 myogenic cells, an in vitro muscle atrophy model, an effect inhibited by IGF1 treatment. In vivo, we observed IGF1 receptor deactivation in immobilized muscle, even in the presence of normal levels of circulating IGF1. Denervation-induced muscle atrophy was accompanied by reduced glucose intake and elevated levels of branched-chain amino acids, effects that were Smad2/3-dependent. Thus, muscle immobilization attenuates IGF1 signals at the receptor rather than the ligand level, leading to Smad2/3 protein accumulation, muscle atrophy, and accompanying metabolic changes.


Asunto(s)
Músculo Esquelético/metabolismo , Atrofia Muscular/metabolismo , Proteína Smad2/metabolismo , Proteína smad3/metabolismo , Aminoácidos de Cadena Ramificada/metabolismo , Animales , Western Blotting , Línea Celular , Glucosa/metabolismo , Factor I del Crecimiento Similar a la Insulina/metabolismo , Factor I del Crecimiento Similar a la Insulina/farmacología , Ratones Noqueados , Ratones Transgénicos , Desnervación Muscular , Fibras Musculares Esqueléticas/citología , Fibras Musculares Esqueléticas/efectos de los fármacos , Fibras Musculares Esqueléticas/metabolismo , Proteínas Musculares/genética , Proteínas Musculares/metabolismo , Músculo Esquelético/inervación , Músculo Esquelético/patología , Atrofia Muscular/etiología , Miostatina/genética , Miostatina/metabolismo , Receptor IGF Tipo 1/genética , Receptor IGF Tipo 1/metabolismo , Restricción Física/efectos adversos , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Proteínas Ligasas SKP Cullina F-box/genética , Proteínas Ligasas SKP Cullina F-box/metabolismo , Proteína Smad2/genética , Proteína smad3/genética , Proteínas de Motivos Tripartitos/genética , Proteínas de Motivos Tripartitos/metabolismo , Ubiquitina-Proteína Ligasas/genética , Ubiquitina-Proteína Ligasas/metabolismo
6.
Biochem Biophys Res Commun ; 482(4): 1430-1436, 2017 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-27974229

RESUMEN

Rapid increases in the number of elderly people have dramatically increased the number of female and male osteoporosis patients. Osteoporosis often causes bone fragility fractures, and males exhibit particularly poor prognosis after these fractures, indicating that control of osteoporosis is crucial to maintain quality of men's lives. However, osteoporosis therapies available for men have lagged behind advances available for women. Here, we show that three selective estrogen receptor modulators (SERMs), namely, raloxifene, bazedoxifene, and tamoxifen, plus the vitamin D analogue ED71, also called eldecalcitol, completely block orchiectomy-induced, testosterone-depleted bone loss in male mice in vivo. Patients treated with hormone deprivation therapy for prostate cancer also exhibit male osteoporosis, and bone management is critical for these patients. Given that androgen replacement therapy is not an option for these patients, our results represent a novel approach potentially useful to control male osteoporosis.


Asunto(s)
Resorción Ósea/prevención & control , Osteoporosis/tratamiento farmacológico , Moduladores Selectivos de los Receptores de Estrógeno/farmacología , Vitamina D/análogos & derivados , Animales , Densidad Ósea , Conservadores de la Densidad Ósea/farmacología , Enfermedades Óseas Metabólicas/inducido químicamente , Enfermedades Óseas Metabólicas/prevención & control , Resorción Ósea/inducido químicamente , Huesos/efectos de los fármacos , Indoles/farmacología , Masculino , Ratones , Ratones Endogámicos C57BL , Orquiectomía , Clorhidrato de Raloxifeno/farmacología , Tamoxifeno/farmacología , Testosterona/deficiencia , Vitamina D/farmacología
7.
Odontology ; 105(2): 262-266, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-27368962

RESUMEN

Oral lichen planus is a chronic inflammatory mucocutaneous disease. Topical use of steroids and other immuno-modulating therapies have been tried for this intractable condition. Nowadays, tacrolimus ointment is used more commonly as a choice for treatment. However, a number of discussions have taken place after tacrolimus was reported to be carcinogenic. This report describes a patient who applied tacrolimus ointment to the lower lip after being diagnosed with oral lichen planus in 2008, and whose lesion developed squamous cell carcinoma in 2010. Since the relationship between tacrolimus and cancer development has been reported in only a few cases, including this case report, the clinician must be careful selecting tacrolimus as a second-line treatment for oral lichen planus.


Asunto(s)
Carcinoma de Células Escamosas/inducido químicamente , Carcinoma de Células Escamosas/diagnóstico , Inmunosupresores/administración & dosificación , Inmunosupresores/efectos adversos , Liquen Plano Oral/diagnóstico , Liquen Plano Oral/tratamiento farmacológico , Neoplasias de la Boca/inducido químicamente , Neoplasias de la Boca/diagnóstico , Tacrolimus/administración & dosificación , Tacrolimus/efectos adversos , Administración Tópica , Biopsia , Candidiasis Bucal/diagnóstico , Candidiasis Bucal/tratamiento farmacológico , Carcinoma de Células Escamosas/cirugía , Diagnóstico Diferencial , Errores Diagnósticos , Humanos , Masculino , Persona de Mediana Edad , Neoplasias de la Boca/cirugía , Colgajos Quirúrgicos
8.
J Biol Chem ; 290(2): 716-26, 2015 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-25404736

RESUMEN

Formation of foreign body giant cells (FBGCs) occurs following implantation of medical devices such as artificial joints and is implicated in implant failure associated with inflammation or microbial infection. Two major macrophage subpopulations, M1 and M2, play different roles in inflammation and wound healing, respectively. Therefore, M1/M2 polarization is crucial for the development of various inflammation-related diseases. Here, we show that FBGCs do not resorb bone but rather express M2 macrophage-like wound healing and inflammation-terminating molecules in vitro. We also found that FBGC formation was significantly inhibited by inflammatory cytokines or infection mimetics in vitro. Interleukin-1 receptor-associated kinase-4 (IRAK4) deficiency did not alter osteoclast formation in vitro, and IRAK4-deficient mice showed normal bone mineral density in vivo. However, IRAK4-deficient mice were protected from excessive osteoclastogenesis induced by IL-1ß in vitro or by LPS, an infection mimetic of Gram-negative bacteria, in vivo. Furthermore, IRAK4 deficiency restored FBGC formation and expression of M2 macrophage markers inhibited by inflammatory cytokines in vitro or by LPS in vivo. Our results demonstrate that osteoclasts and FBGCs are reciprocally regulated and identify IRAK4 as a potential therapeutic target to inhibit stimulated osteoclastogenesis and rescue inhibited FBGC formation under inflammatory and infectious conditions without altering physiological bone resorption.


Asunto(s)
Diferenciación Celular/genética , Células Gigantes de Cuerpo Extraño/metabolismo , Inflamación/metabolismo , Quinasas Asociadas a Receptores de Interleucina-1/genética , Animales , Resorción Ósea/genética , Resorción Ósea/metabolismo , Regulación del Desarrollo de la Expresión Génica , Inflamación/patología , Quinasas Asociadas a Receptores de Interleucina-1/metabolismo , Macrófagos/metabolismo , Ratones , Osteoclastos/metabolismo , Osteólisis/genética , Osteólisis/patología
9.
J Biol Chem ; 290(28): 17106-15, 2015 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-25998127

RESUMEN

Diabetes mellitus (DM) is frequently accompanied by complications, such as peripheral nerve neuropathy. Schwann cells play a pivotal role in regulating peripheral nerve function and conduction velocity; however, changes in Schwann cell differentiation status in DM are not fully understood. Here, we report that Schwann cells de-differentiate into immature cells under hyperglycemic conditions as a result of sorbitol accumulation and decreased Igf1 expression in those cells. We found that de-differentiated Schwann cells could be re-differentiated in vitro into mature cells by treatment with an aldose reductase inhibitor, to reduce sorbitol levels, or with vitamin D3, to elevate Igf1 expression. In vivo DM models exhibited significantly reduced nerve function and conduction, Schwann cell de-differentiation, peripheral nerve de-myelination, and all conditions were significantly rescued by aldose reductase inhibitor or vitamin D3 administration. These findings reveal mechanisms underlying pathological changes in Schwann cells seen in DM and suggest ways to treat neurological conditions associated with this condition.


Asunto(s)
Hiperglucemia/metabolismo , Hiperglucemia/patología , Factor I del Crecimiento Similar a la Insulina/metabolismo , Células de Schwann/metabolismo , Células de Schwann/patología , Sorbitol/metabolismo , Aldehído Reductasa/antagonistas & inhibidores , Animales , Calcitriol/análogos & derivados , Calcitriol/farmacología , Desdiferenciación Celular/fisiología , Células Cultivadas , Enfermedades Desmielinizantes/metabolismo , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/patología , Neuropatías Diabéticas/metabolismo , Neuropatías Diabéticas/patología , Regulación hacia Abajo , Inhibidores Enzimáticos/farmacología , Glucosa/metabolismo , Técnicas In Vitro , Ratones , Ratones Endogámicos C57BL , Modelos Neurológicos , Ratas , Rodanina/análogos & derivados , Rodanina/farmacología , Células de Schwann/efectos de los fármacos , Nervio Ciático/metabolismo , Nervio Ciático/patología , Tiazolidinas/farmacología , Vitamina D/análogos & derivados
10.
Biochem Biophys Res Commun ; 480(4): 662-668, 2016 11 25.
Artículo en Inglés | MEDLINE | ID: mdl-27983979

RESUMEN

Both bone and muscle volume is concomitantly reduced under immobilization conditions; however, no single drug is currently available to block these outcomes simultaneously. Bisphosphonates are utilized clinically to inhibit osteoclast-dependent bone resorption, but their effects on muscle are largely unknown. Here we show that skeletal muscle is a direct target of the bisphosphonate ibandronate (IBN) and that reduced muscle volume and induction of Atrogin-1 and MuRF1, both atrogenes, are significantly inhibited by IBN administration in vivo using a mouse model of muscle atrophy. IBN treatment also significantly blocked immobilization-induced bone loss in vivo. We also report that expression of Atrogin-1 and MuRF1 and accumulation of Smad2/3 proteins, which are upstream of atrogines, occurred following serum starvation of myogenic C2C12 cells in vitro, effects significantly inhibited by IBN treatment. Interestingly, IBN effects on C2C12 cells were abrogated by MG132, an ubiquitin/proteasome inhibitor, suggesting that IBN functions via the ubiquitin-proteasome system. Our findings lend new insight into the role of IBN in preventing muscle atrophy.


Asunto(s)
Resorción Ósea/prevención & control , Resorción Ósea/fisiopatología , Difosfonatos/farmacología , Inmovilización/efectos adversos , Atrofia Muscular/prevención & control , Atrofia Muscular/fisiopatología , Animales , Conservadores de la Densidad Ósea/farmacología , Resorción Ósea/etiología , Línea Celular , Relación Dosis-Respuesta a Droga , Femenino , Ácido Ibandrónico , Ratones , Ratones Endogámicos C57BL , Atrofia Muscular/etiología , Tamaño de los Órganos/efectos de los fármacos , Complejo de la Endopetidasa Proteasomal/metabolismo , Resultado del Tratamiento , Ubiquitinación/efectos de los fármacos
11.
Biochem Biophys Res Commun ; 470(2): 391-396, 2016 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-26792721

RESUMEN

The number of osteoporosis patients is increasing not only in women but in men. Male osteoporosis occurs due to aging or androgen depletion therapies, leading to fractures. However, molecular mechanisms underlying male osteoporosis remain unidentified. Here, we show that hypoxia inducible factor 1 alpha (Hif1α) is required for development of testosterone deficiency-induced male osteoporosis. We found that in mice Hif1α protein accumulates in osteoclasts following orchidectomy (ORX) in vivo. In vitro, Hif1α protein accumulated in osteoclasts cultured in hypoxic conditions, but Hif1α protein rather than mRNA levels were suppressed by testosterone treatment, even in hypoxia. Administration of a Hif1α inhibitor to ORX mice abrogated testosterone deficiency-induced osteoclast activation and bone loss but did not alter osteoclast activities or bone phenotypes in sham-operated, testosterone-sufficient animals. We conclude that Hif1α protein accumulation due to testosterone-deficiency promotes development of male osteoporosis. Thus Hif1α protein could be targeted to inhibit pathologically-activated osteoclasts under testosterone-deficient conditions to treat male osteoporosis patients.


Asunto(s)
Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Osteoclastos/metabolismo , Osteoclastos/patología , Osteoporosis/metabolismo , Osteoporosis/patología , Testosterona/metabolismo , Animales , Masculino , Ratones , Ratones Endogámicos C57BL
12.
J Bone Miner Metab ; 34(5): 526-31, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26202855

RESUMEN

The increasing number of osteoporosis patients is a pressing issue worldwide. Osteoporosis frequently causes fragility fractures, limiting activities of daily life and increasing mortality. Many osteoporosis patients take numerous medicines due to other health issues; thus, it would be preferable if a single medicine could ameliorate osteoporosis and other conditions. Here, we screened 96 randomly selected drugs targeting various diseases for their ability to inhibit differentiation of osteoclasts, which play a pivotal role in development of osteoporosis, and identified methotrexate (MTX), as a potential inhibitor. MTX is currently used to treat sarcomas or leukemic malignancies or auto-inflammatory diseases such as rheumatoid arthritis (RA) through its anti-proliferative and immunosuppressive activities; however, a direct effect on osteoclast differentiation has not been shown. Here, we report that osteoclast formation and expression of osteoclastic genes such as NFATc1 and DC-STAMP, which are induced by the cytokine RANKL, are significantly inhibited by MTX. We found that RANKL-dependent calcium (Ca) influx into osteoclast progenitors was significantly inhibited by MTX. RA patients often develop osteoporosis, and osteoclasts are reportedly required for joint destruction; thus, MTX treatment could have a beneficial effect on RA patients exhibiting high osteoclast activity by preventing both osteoporosis and joint destruction.


Asunto(s)
Calcio/metabolismo , Metotrexato/farmacología , Osteoclastos/efectos de los fármacos , Osteogénesis/efectos de los fármacos , Células Madre/efectos de los fármacos , Animales , Células Cultivadas , Ratones Endogámicos C57BL , Osteoclastos/metabolismo , Ligando RANK/farmacología , Células Madre/metabolismo
13.
Biochem Biophys Res Commun ; 457(3): 451-6, 2015 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-25597995

RESUMEN

Bone mass is tightly controlled by a balance between osteoclast and osteoblast activities. Although these cell types mature via different pathways, some factors reportedly regulate differentiation of both. Here, in a search for factors governing osteoblastogenesis but also expressed in osteoclasts to control both cell types by one molecule, we identified B cell lymphoma 6 (Bcl6) as one of those factors and show that it promotes osteoblast differentiation. Bcl6 was previously shown to negatively regulate osteoclastogenesis. We report that lack of Bcl6 results in significant inhibition of osteoblastogensis in vivo and in vitro and in defects in secondary ossification center formation in vivo. Signal transducer and activator of transcription 1 (Stat1) reportedly attenuates osteoblast differentiation by inhibiting nuclear translocation of runt-related transcription factor 2 (Runx2), which is essential for osteoblast differentiation. We found that lack of Bcl6 resulted in significant elevation of Stat1 mRNA and protein expression in osteoblasts and showed that Stat1 is a direct target of Bcl6 using a chromatin immune-precipitation assay. Mice lacking both Bcl6 and Stat1 (DKO) exhibited significant rescue of bone mass and osteoblastic parameters as well as partial rescue of secondary ossification center formation compared with Bcl6-deficient mice in vivo. Altered osteoblastogenesis in Bcl6-deficient cells was also restored in DKO in vitro. Thus, Bcl6 plays crucial roles in regulating both osteoblast activation and osteoclast inhibition.


Asunto(s)
Proteínas de Unión al ADN/metabolismo , Osteoblastos/metabolismo , Osteogénesis/fisiología , Factor de Transcripción STAT1/antagonistas & inhibidores , Células 3T3 , Animales , Sitios de Unión/genética , Remodelación Ósea/genética , Remodelación Ósea/fisiología , Diferenciación Celular/genética , Diferenciación Celular/fisiología , ADN/genética , ADN/metabolismo , Proteínas de Unión al ADN/deficiencia , Proteínas de Unión al ADN/genética , Femenino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Osteoblastos/citología , Osteoclastos/citología , Osteoclastos/metabolismo , Osteogénesis/genética , Regiones Promotoras Genéticas , Proteínas Proto-Oncogénicas c-bcl-6 , ARN Mensajero/genética , ARN Mensajero/metabolismo , Factor de Transcripción STAT1/deficiencia , Factor de Transcripción STAT1/genética
14.
J Bone Miner Metab ; 33(2): 135-41, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24633489

RESUMEN

Rheumatoid arthritis (RA) is a multifactorial disease caused by genetic and environmental factors: however, precise molecular mechanisms underlying its pathogenesis remain largely unknown. Treatment of RA patients with disease-modifying biological agents occasionally promotes Mycobacterium tuberculosis infection or recurrence of M. tuberculosis, although how infection promotes arthritis has not been characterized. Here, we found that arthritis phenotypes in a collagen-induced mouse model were evident only when killed M. tuberculosis was co-administered. Treatment of cultured macrophages with killed M. tuberculosis promoted production of IL-6, a major inflammatory cytokine in RA patients, while similar treatment of TLR2-deficient macrophages failed to induce IL-6 expression. Arthritis scores, joint destruction, and serum IL-6 levels were all significantly ameliorated in TLR2-deficient compared with wild-type mice, even in animals treated with killed M. tuberculosis. These results suggest that M. tuberculosis infection enhances arthritis development and that TLR2 could serve as a therapeutic target for some forms of the disease.


Asunto(s)
Artritis Reumatoide/mortalidad , Artritis Reumatoide/patología , Mycobacterium tuberculosis/fisiología , Receptor Toll-Like 2/metabolismo , Tuberculosis/microbiología , Tuberculosis/patología , Animales , Artritis Reumatoide/metabolismo , Células Cultivadas , Inflamación/metabolismo , Interleucina-6/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos DBA , Tuberculosis/metabolismo
15.
Molecules ; 20(11): 20230-9, 2015 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-26569206

RESUMEN

The anti-inflammatory activity of auraptene (AUR), a citrus coumarin, in peripheral tissues is well-known, and we previously demonstrated that AUR exerts anti-inflammatory effects in the ischemic brain; the treatment of mice with AUR for eight days immediately after ischemic surgery suppressed demise and neuronal cell death in the hippocampus, possibly through its anti-inflammatory effects in the brain. We suggested that these effects were at least partly mediated by the suppression of inflammatory mediators derived from astrocytes. The present study showed that (1) AUR, as a pretreatment for five days before and another three days after ischemic surgery, suppressed microglial activation, cyclooxygenase (COX)-2 expression in astrocytes, and COX-2 mRNA expression in the hippocampus; (2) AUR suppressed the lipopolysaccharide-induced expression of COX-2 mRNA and the mRNA of pro-inflammatory cytokines in cultured astrocytes; (3) AUR was still detectable in the brain 60 min after its intraperitoneal administration. These results support our previous suggestion that AUR directly exerts anti-inflammatory effects on the brain.


Asunto(s)
Antiinflamatorios/farmacología , Encéfalo/efectos de los fármacos , Cumarinas/farmacología , Animales , Antiinflamatorios/administración & dosificación , Encéfalo/metabolismo , Encéfalo/patología , Isquemia Encefálica/tratamiento farmacológico , Isquemia Encefálica/genética , Isquemia Encefálica/metabolismo , Isquemia Encefálica/mortalidad , Cumarinas/administración & dosificación , Ciclooxigenasa 2/genética , Ciclooxigenasa 2/metabolismo , Citocinas/genética , Citocinas/metabolismo , Modelos Animales de Enfermedad , Regulación de la Expresión Génica/efectos de los fármacos , Proteína Ácida Fibrilar de la Glía/genética , Proteína Ácida Fibrilar de la Glía/metabolismo , Hipocampo/efectos de los fármacos , Hipocampo/metabolismo , Mediadores de Inflamación/metabolismo , Masculino , Ratones
16.
Diagnostics (Basel) ; 14(4)2024 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-38396459

RESUMEN

Flow cytometry is a vital diagnostic tool for hematologic and immunologic disorders, but manual analysis is prone to variation and time-consuming. Over the last decade, artificial intelligence (AI) has advanced significantly. In this study, we developed and validated an AI-assisted flow cytometry workflow using 379 clinical cases from 2021, employing a 3-tube, 10-color flow panel with 21 antibodies for primary immunodeficiency diseases and related immunological disorders. The AI software (DeepFlow™, version 2.1.1) is fully automated, reducing analysis time to under 5 min per case. It interacts with hematopatholoists for manual gating adjustments when necessary. Using proprietary multidimensional density-phenotype coupling algorithm, the AI model accurately classifies and enumerates T, B, and NK cells, along with important immune cell subsets, including CD4+ helper T cells, CD8+ cytotoxic T cells, CD3+/CD4-/CD8- double-negative T cells, and class-switched or non-switched B cells. Compared to manual analysis with hematopathologist-determined lymphocyte subset percentages as the gold standard, the AI model exhibited a strong correlation (r > 0.9) across lymphocyte subsets. This study highlights the accuracy and efficiency of AI-assisted flow cytometry in diagnosing immunological disorders in a clinical setting, providing a transformative approach within a concise timeframe.

17.
Int J Med Mushrooms ; 15(2): 115-26, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23557364

RESUMEN

The aim of this work was to characterize an antibody response to ß-glucan (BG), a major component of the fungal cell wall, at each isotype in human sera. The titer and reactivity of the anti-human BG antibody were examined using enzyme-linked immunosorbant assay plates coated with Candida soluble cell wall ß-glucan as a standard antigen. The antibody was detected using anti-human immunoglobulin (Ig) G, IgM, and IgA. Its major class was IgG in all subjects. The antibody titer varied significantly. The anti-BG antibody showed greater reactivity to ß-glucans derived from pathogenic fungi than monoglycosyl-branched ß-glucans derived from mycelia culture medium. In addition, it was suggested that the anti-BG IgM antibody was bound relatively strongly to the ß1,3-glucan backbone and the anti-BG IgG antibody to ß1,6-glucan. The anti-BG antibody plays a variety of roles, according to class, in the host's response to fungi. We propose a new index of human response to ß-glucan that effects the understanding of the response to ß-glucan in humans.


Asunto(s)
Anticuerpos/sangre , Aspergillus/citología , Pared Celular/química , Pared Celular/inmunología , beta-Glucanos/inmunología , Adulto , Especificidad de Anticuerpos , Aspergillus/metabolismo , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Inmunoglobulina A/sangre , Inmunoglobulina G/sangre , Inmunoglobulina M/sangre , Masculino , Persona de Mediana Edad , Adulto Joven
18.
Carbohydr Res ; 534: 108961, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37769374

RESUMEN

The formation of carbon monoxide (CO) from glucose and cellulose by the treatment with various ionic liquids was studied. Ionic liquids with an imidazolium structure as cation and the chloride or acetate as anion were used. Additionally, 1,8-diazabicyclo [5.4.0]undec-7-ene (DBU) was employed as an additive. CO was generated from glucose with a maximum yield of 0.57 mol% after 90 min of treatment at 120 °C in the reaction system in which DBU was added to the ionic liquid. Pyrolysis above 600 °C has been commonly employed for the gasification of lignocellullosics to produce useful gases such as CO. However, this study has revealed that gasification of lignocellullosics to produce CO can occur at significantly lower temperature, specifically at 120 °C.


Asunto(s)
Celulosa , Líquidos Iónicos , Celulosa/química , Líquidos Iónicos/química , Glucosa/química , Aniones/química , Cloruros
19.
Anal Chim Acta ; 1242: 340798, 2023 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-36657892

RESUMEN

Carbonates play a crucial role in the water and carbon cycles of both geochemical and cosmochemical environments. As carbonates do not exist homogeneously with other minerals in rocks and sands of various sizes, an analytical method that simultaneously satisfies non-destructivity and high spatial resolution has been desired. Further, the ability of semi-quantitative analysis with carbonates-selectivity and without any pre-treatments is added, for its applicability would be extended to remote sensing for deep sea and outer spaces. Here, we focused on the application of micro-Raman spectroscopy, where the vibrational wavenumbers of the translational (T) and librational (L) modes of carbonates are sensitively related to their cation composition. By comparing the semi-quantitative information obtained by X-ray fluorescence spectroscopy, it was found that these vibrational wavenumbers are approximately linearly related to the cation composition. Consequently, a conversion matrix was proposed to estimate the cation composition from the T and L mode vibrational wavenumbers. This method is universally applicable to any cation composition in carbonates, with no background information on the analyte required. To improve the accuracy, conversion matrices were further optimized to three solid-solution series of carbonates. It is worth noting that the proposed conversion matrices are free from matrix effects and do not depend on the total amount of carbonate in a sample. Therefore, the proposed method provides a useful analytical basis for remote sensing of the cation composition of carbonates, both in terrestrial and extra-terrestrial environments.

20.
Anal Sci ; 39(8): 1279-1285, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37079215

RESUMEN

Dolomite (CaMg(CO3)2) is an abundant carbonate mineral contained in sedimentary rocks and plays significant roles in water and carbon cycle in geo/cosmochemical environments. Since the cation compositions of carbonates are sensitive to the aqueous environment where they were precipitated and persisted, quantitative analysis of their cation compositions provides valuable information on the aqueous environments and their changes. The difficulty for the analysis of natural dolomite is that Mg2+ is continuously substituted by Fe2+ or Mn2+, and hence they sometimes possess micrometer-scale heterogeneity. Such heterogeneity carries quite important information on the gradual changes in aqueous environments due to changes in thermodynamic conditions and/or aqueous chemical compositions. In the present study, we explored a new quantitative scale to assess such heterogeneity of cation composition in natural dolomite and ferroan dolomite by combining X-ray fluorescence (XRF) and Raman spectroscopy. While the Fe + Mn content differed spot-by-spot, it was found that the Raman wavenumber and Fe + Mn content linearly correlated with each other. Since the spatial resolution of micro-Raman spectroscopy is as high as 1 µm, it does not require vacuum conditions, and is free from so-called matrix effect faced in other methods utilizing X-Rays and electron beams, the proposed qualitative analytical scale can provide a useful tool to assess the cation compositions in dolomites found in nature.

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