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1.
J Fish Biol ; 103(1): 73-90, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37088957

RESUMEN

Apristurus ovicorrugatus, a new species of deepwater catshark, is described from northwestern Australia. Unique egg cases belonging to an unknown species of Apristurus prompted a more detailed investigation of Apristurus specimens off northwestern Australia. One specimen previously identified as A. sinensis collected off Dampier Archipelago was found gravid with a single egg case. Removal of this egg case confirmed that this species was responsible for producing the unique egg cases previously recorded. The egg cases of this species have strong T-shaped longitudinal ridges on the dorsal and ventral surfaces which are unique in the genus Apristurus. The ridges most closely resemble those present in Bythaelurus canescens from South America, but are larger and always T-shaped. The holotype is closest morphologically to A. sinensis but differs in having a medium brown buccal cavity (vs. jet black), ridged egg cases (vs. smooth egg cases), fewer intestinal spiral valve turns and larger pectoral fins. The holotype is also similar, and closest on a molecular level, to A. nakayai with which it shares a unique synapomorphic character, the white shiny iris (apomorphic within the genus). A late-term embryo removed from an egg case superficially resembled the holotype except in having two parallel rows of enlarged dermal denticles on the dorsolateral predorsal surface. Recent nomenclatural changes to the genera Apristurus and Pentanchus are discussed and challenged. This study highlights the important contribution that egg case morphology has on oviparous elasmobranch taxonomy.


Asunto(s)
Tiburones , Animales , Tiburones/anatomía & histología , América del Sur , Australia
2.
Arterioscler Thromb Vasc Biol ; 38(7): 1454-1467, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29748333

RESUMEN

OBJECTIVE: Reverse cholesterol transport (RCT) is a major mechanism by which HDL (high-density lipoprotein) protects against atherosclerosis. Endothelial lipase (EL) reportedly reduces HDL levels, which, in theory, would increase atherosclerosis. However, it remains unclear whether EL affects RCT in vivo. APPROACH AND RESULTS: Adenoviral vectors expressing EL or luciferase were intravenously injected into mice, and a macrophage RCT assay was performed. As expected, hepatic EL overexpression markedly reduced HDL levels. In parallel, plasma 3H-cholesterol counts from the EL-expressing mice decreased by 85% compared with control. Surprisingly, there was no difference in fecal 3H-cholesterol excretion between the groups. Kinetic studies revealed increased catabolism/hepatic uptake of 3HDL-cholesteryl ether, resulting in no change in fecal HDL-cholesteryl ester excretion in the mice. To explore underlying mechanisms for the preservation of RCT despite low HDL levels in the EL-expressing mice, we investigated the effects of hepatic SR-BI (scavenger receptor class B type I) knockdown. RCT assay revealed that knockdown of SR-BI alone reduced fecal excretion of macrophage-derived 3H-cholesterol. Interestingly, hepatic EL overexpression under SR-BI inhibition further attenuated fecal tracer counts as compared with control. Finally, we observed that EL overexpression enhanced in vivo RCT under pharmacological inhibition of hepatic ABCA1 (ATP-binding cassette transporter A1) by probucol. CONCLUSIONS: Hepatic EL expression compensates for reduced macrophage-derived cholesterol efflux to plasma because of low HDL levels by promoting cholesterol excretion to bile/feces via an SR-BI pathway, maintaining overall RCT in vivo. In contrast, EL-modified HDL might negatively regulate RCT via hepatic ABCA1. Despite extreme hypoalphalipoproteinemia, RCT is maintained in EL-expressing mice via SR-BI/ABCA1-dependent pathways.


Asunto(s)
Transportador 1 de Casete de Unión a ATP/metabolismo , HDL-Colesterol/sangre , Lipasa/biosíntesis , Hígado/enzimología , Macrófagos Peritoneales/metabolismo , Receptores Depuradores de Clase B/metabolismo , Adenoviridae/genética , Animales , Inducción Enzimática , Técnicas de Transferencia de Gen , Vectores Genéticos , Células Hep G2 , Humanos , Lipasa/genética , Ratones , Ratones Endogámicos C57BL , MicroARNs/genética , MicroARNs/metabolismo , Células RAW 264.7 , Interferencia de ARN , Receptores Depuradores de Clase B/genética
3.
Curr Opin Lipidol ; 29(1): 18-23, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-29135690

RESUMEN

PURPOSE OF REVIEW: Accumulating evidence has provided new insights regarding potentially effective therapeutic options targeting modulation of HDL metabolism, resulting in the prevention of cardiovascular diseases. The gut microbiota has now been convincingly linked to host health, but its impact on host lipid metabolism, especially HDL metabolism, remains poorly understood. This review focuses on the recent progress in establishing associations between gut microbiota and host HDL metabolism. It also discusses causality and mechanisms, and how to translate the findings into clinical use. RECENT FINDINGS: Recent human and animal studies have demonstrated that the gut microbiota composition can explain a substantial proportion of the individual variation in host blood lipid profiles. In addition, signaling molecules produced by gut microbiota have been shown to have potent effects on reverse cholesterol transport, a crucial atheroprotective function of HDL, which could subsequently influence the development of atherosclerosis. Ultimately, selective manipulation of gut microbiota may serve as an ideal therapeutic approach for improving HDL function and cardiovascular risk, although further studies are needed for a better understanding of which specific bacteria, or alternatively, which bacterial metabolites, are appropriate targets. SUMMARY: We are just beginning to understand how the gut microbiota, a newly recognized endocrine organ system, influences HDL metabolism and atherosclerotic diseases. From recent experimental and clinical perspectives, it can be targeted for therapeutic benefit with respect to HDL function and cardiovascular diseases.


Asunto(s)
HDL-Colesterol/metabolismo , Microbioma Gastrointestinal , Tracto Gastrointestinal/metabolismo , Tracto Gastrointestinal/microbiología , Animales , Humanos , Metabolismo de los Lípidos
4.
Arterioscler Thromb Vasc Biol ; 36(4): 591-7, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26848156

RESUMEN

OBJECTIVE: Oxidized products of probucol, spiroquinone and diphenoquinone, were shown to increase cell cholesterol release and plasma high-density lipoprotein (HDL) by inhibiting degradation of ATP-binding cassette transporter A1. We investigated whether these compounds enhance reverse cholesterol transport in mice. APPROACH AND RESULTS: Spiroquinone and diphenoquinone increased ATP-binding cassette transporter A1 protein (2.8- and 2.6-fold, respectively, P<0.01) and apolipoprotein A-I-mediated cholesterol release (1.4- and 1.4-fold, P<0.01 and P<0.05, respectively) in RAW264.7 cells. However, diphenoquinone, but not spiroquinone, enhanced cholesterol efflux to HDL (+12%, P<0.05), whereas both increased ATP-binding cassette transporter G1 protein, by 1.8- and 1.6-fold, respectively. When given orally to mice, both compounds significantly increased plasma HDL-cholesterol, by 19% and 20%, respectively (P<0.05), accompanied by an increase in hepatic and macrophage ATP-binding cassette transporter A1 but not ATP-binding cassette transporter G1. We next evaluated in vivo reverse cholesterol transport by injecting RAW264.7 cells labeled with (3)H-cholesterol intraperitoneally into mice. Both spiroquinone and diphenoquinone increased fecal excretion of the macrophage-derived (3)H-tracer, by 25% and 28% (P<0.01 and P<0.05), respectively. spiroquinone/diphenoquinone did not affect fecal excretion of HDL-derived (3)H-cholesterol, implying that macrophage-to-plasma was the most important step in spiroquinone/diphenoquinone-mediated promotion of in vivo reverse cholesterol transport. Finally, spiroquinone significantly reduced aortic atherosclerosis in apolipoprotein E null mice when compared with the vehicle. CONCLUSIONS: Spiroquinone and diphenoquinone increase functional ATP-binding cassette transporter A1 in both the macrophages and the liver, elevate plasma HDL-cholesterol, and promote overall reverse cholesterol transport in vivo. These compounds are promising as therapeutic reagents against atherosclerosis.


Asunto(s)
Transportador 1 de Casete de Unión a ATP/efectos de los fármacos , Androstadienos/farmacología , Anticolesterolemiantes/farmacología , Aorta/efectos de los fármacos , Enfermedades de la Aorta/prevención & control , Aterosclerosis/prevención & control , Colesterol/sangre , Hipercolesterolemia/tratamiento farmacológico , Macrófagos/efectos de los fármacos , Probucol/farmacología , Quinonas/farmacología , Transportador 1 de Casete de Unión a ATP/metabolismo , Animales , Aorta/metabolismo , Aorta/patología , Enfermedades de la Aorta/sangre , Enfermedades de la Aorta/genética , Enfermedades de la Aorta/patología , Apolipoproteína A-I/sangre , Apolipoproteínas E/deficiencia , Apolipoproteínas E/genética , Aterosclerosis/sangre , Aterosclerosis/genética , Aterosclerosis/patología , Transporte Biológico , HDL-Colesterol/sangre , Modelos Animales de Enfermedad , Heces/química , Hipercolesterolemia/sangre , Hipercolesterolemia/genética , Hígado/efectos de los fármacos , Hígado/metabolismo , Macrófagos/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Oxidación-Reducción , Placa Aterosclerótica , Células RAW 264.7 , Factores de Tiempo
5.
J Ultrasound Med ; 36(3): 659-664, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-28127793

RESUMEN

Primary mural endocarditis is an extremely rare infection in which nonvalvular endocardial involvement is seen without any cardiac structural abnormalities such as ventricular septal defects. The rapid and precise diagnosis of this disease remains challenging. We present 2 cases (67- and 47-year-old male patients) of pathologically confirmed primary mural endocarditis that could have been detected by initial transthoracic echocardiography in the emergency department. Transthoracic echocardiography and transesophageal echocardiography play critical roles in the early recognition and confirmation of primary mural endocarditis.


Asunto(s)
Ecocardiografía Transesofágica , Endocarditis/diagnóstico , Endocarditis/terapia , Infecciones Estafilocócicas/diagnóstico , Infecciones Estafilocócicas/terapia , Anciano , Diagnóstico Diferencial , Endocarditis/diagnóstico por imagen , Resultado Fatal , Humanos , Masculino , Persona de Mediana Edad
6.
Biochim Biophys Acta ; 1841(9): 1247-55, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24989153

RESUMEN

Reverse cholesterol transport (RCT) is pivotal in the return of excess cholesterol from peripheral tissues to the liver for excretion in bile and eventually feces. RCT from macrophages is a critical anti-atherogenicity mechanism of HDL. As the cholesterol absorption inhibitor ezetimibe promoted RCT in mice, which lack cholesterol ester transfer protein (CETP), we investigated its effects in hamsters, which have CETP. A high-cholesterol diet (HC) increased cholesterol levels throughout lipoprotein fractions and ezetimibe markedly reduced VLDL/LDL cholesterol levels under both normal chow (NC) and HC. However, ezetimibe did not affect and reduced HDL-cholesterol levels under NC and HC, respectively. Intraperitoneal injection of (3)H-cholesterol pre-labeled macrophages in an in vivo RCT assay increased tracer accumulation in the liver but reduced it in bile under HC, and these changes were completely cancelled by ezetimibe. Under both NC and HC, ezetimibe reduced tracer levels in the liver but increased them in feces, indicating promotion of RCT in vivo. We performed a RCT assay using hamsters subjected to bile duct ligation (BDL) to clarify whether a transintestinal cholesterol efflux (TICE) pathway contributes to ezetimibe's enhancement of RCT. BDL markedly inhibited macrophage-derived (3)H-cholesterol excretion to feces and cancelled ezetimibe's stimulatory effect on RCT, suggesting that biliary cholesterol excretion is a major contributor in RCT promotion by ezetimibe but the contribution of the TICE pathway is minimal. In conclusions, ezetimibe exerts an additive anti-atherogenic property by enhancing RCT in hamsters. Our findings suggest that this property is independent of the TICE pathway.


Asunto(s)
Anticolesterolemiantes/farmacología , Azetidinas/farmacología , Bilis/efectos de los fármacos , HDL-Colesterol/metabolismo , Hígado/efectos de los fármacos , Macrófagos/efectos de los fármacos , Animales , Bilis/metabolismo , Conductos Biliares/cirugía , Transporte Biológico/efectos de los fármacos , Proteínas de Transferencia de Ésteres de Colesterol/metabolismo , LDL-Colesterol/metabolismo , VLDL-Colesterol/metabolismo , Cricetinae , Dieta , Ezetimiba , Heces/química , Hígado/metabolismo , Macrófagos/citología , Macrófagos/metabolismo , Masculino , Tritio
7.
Arterioscler Thromb Vasc Biol ; 34(6): 1171-8, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24675665

RESUMEN

OBJECTIVE: Low-density lipoprotein receptor (LDLR) is degraded by inducible degrader of LDLR (Idol) and protein convertase subtilisin/kexin type 9 (PCSK9), thereby regulating circulating LDL levels. However, it remains unclear whether, and if so how, these LDLR degraders affect each other. We therefore investigated effects of liver-specific expression of Idol on LDL/PCSK9 metabolism in mice and hamsters. APPROACH AND RESULTS: Injection of adenoviral vector expressing Idol (Ad-Idol) induced a liver-specific reduction in LDLR expression which, in turn, increased very-low-density lipoprotein/LDL cholesterol levels in wild-type mice because of delayed LDL catabolism. Interestingly, hepatic Idol overexpression markedly increased plasma PCSK9 levels. In LDLR-deficient mice, plasma PCSK9 levels were already elevated at baseline and unchanged by Idol overexpression, which was comparable with the observation for Ad-Idol-injected wild-type mice, indicating that Idol-induced PCSK9 elevation depended on LDLR. In wild-type mice, but not in LDLR-deficient mice, Ad-Idol enhanced hepatic PCSK9 expression, with activation of sterol regulatory element-binding protein 2 and subsequently increased expression of its target genes. Supporting in vivo findings, Idol transactivated PCSK9/LDLR in sterol regulatory element-binding protein 2/LDLR-dependent manners in vitro. Furthermore, an in vivo kinetic study using (125)I-labeled PCSK9 revealed delayed clearance of circulating PCSK9, which could be another mechanism. Finally, to extend these findings into cholesteryl ester transfer protein-expressing animals, we repeated the above in vivo experiments in hamsters and obtained similar results. CONCLUSIONS: A vicious cycle in LDLR degradation might be generated by PCSK9 induced by hepatic Idol overexpression via dual mechanisms: sterol regulatory element-binding protein 2/LDLR. Furthermore, these effects would be independent of cholesteryl ester transfer protein expression.


Asunto(s)
Hígado/metabolismo , Proproteína Convertasas/sangre , Receptores de LDL/fisiología , Serina Endopeptidasas/sangre , Transducción de Señal , Proteína 2 de Unión a Elementos Reguladores de Esteroles/fisiología , Ubiquitina-Proteína Ligasas/fisiología , Animales , Proteínas de Transferencia de Ésteres de Colesterol/fisiología , Cricetinae , Células Hep G2 , Humanos , Lipoproteínas LDL/metabolismo , Receptores X del Hígado , Mesocricetus , Ratones , Ratones Endogámicos C57BL , Receptores Nucleares Huérfanos/fisiología , Proproteína Convertasa 9 , Proproteína Convertasas/fisiología , Serina Endopeptidasas/fisiología
8.
Biochim Biophys Acta ; 1831(8): 1402-11, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23747827

RESUMEN

Stearoyl-coenzyme A desaturase 1 (SCD1) is the rate-limiting enzyme in the synthesis of monounsaturated fatty acids. However, the impact of SCD1 on atherosclerosis remains unclear. The aim of this study was to determine whether SCD1 affects macrophage reverse cholesterol transport (RCT) in mice. Compared to the control, adenoviral-mediated SCD1 overexpression in RAW264.7 macrophages increased cholesterol efflux to HDL, but not to apoA-I, without clear changes in ABCA1, ABCG1 and SR-BI expressions. While knockdown of ABCG1 and SR-BI did not affect the SCD1-induced cholesterol efflux to HDL, SCD1-overexpressing macrophages promoted the formation of both normal- and large-sized HDL in media, accompanying increased apolipoprotein A-I levels in HDL fractions. Transformation to larger particles of HDL was independently confirmed by nuclear magnetic resonance-based lipoprotein analysis. Interestingly, media transfer assays revealed that HDL generated by SCD1 had enhanced cholesterol efflux potential, indicating that SCD1 transformed HDL to a more anti-atherogenic phenotype. To study macrophage RCT in vivo, (3)H-cholesterol-labeled RAW264.7 cells overexpressing SCD1 or the control were intraperitoneally injected into mice. Supporting the in vitro data, injection of SCD1-macrophages resulted in significant increases in (3)H-tracer in plasma, liver, and feces compared to the control. Moreover, there was a shift towards larger particles in the (3)H-tracer distribution of HDL fractions obtained from the mice. In conclusion, macrophage-specific SCD1 overexpression promotes overall RCT through increased cholesterol efflux to HDL, suggesting that macrophage SCD1 achieves an anti-atherogenic effect by enhancing RCT.


Asunto(s)
Colesterol/metabolismo , Regulación Enzimológica de la Expresión Génica , Lipoproteínas HDL/metabolismo , Macrófagos/enzimología , Estearoil-CoA Desaturasa/biosíntesis , Transportador 1 de Casete de Unión a ATP , Transportador de Casetes de Unión a ATP, Subfamilia G, Miembro 1 , Transportadoras de Casetes de Unión a ATP/genética , Transportadoras de Casetes de Unión a ATP/metabolismo , Animales , Aterosclerosis/enzimología , Aterosclerosis/genética , Aterosclerosis/patología , Aterosclerosis/terapia , Transporte Biológico Activo/genética , Línea Celular , Colesterol/genética , Humanos , Lipoproteínas/genética , Lipoproteínas/metabolismo , Lipoproteínas HDL/genética , Macrófagos/patología , Ratones , Estearoil-CoA Desaturasa/genética
9.
Korean J Parasitol ; 52(2): 211-4, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24850968

RESUMEN

Epidemiological situation of taeniasis in Mongolia was assessed based on mitochondrial DNA identification of the parasite species. Multiplex PCR was used on a total of 194 proglottid specimens of Taenia species and copro-PCR and loop-mediated isothermal amplification (LAMP) assays were utilized for detection of copro-DNA of 37 fecal samples from taeniasis patients submitted to the Mongolian National Center for Communicable Diseases (NCCD) from 2002 to 2012. In addition, 4 out of 44 calcified cysts in beef kept in formalin since 2003 were evaluated for histopathological confirmation of cattle cysticercosis. All proglottid specimens and stool samples were confirmed to be Taenia saginata by multiplex PCR and by copro-PCR and LAMP, respectively. Cysts collected from cattle were morphologically confirmed to be metacestodes of Taenia species. T. saginata taeniasis was identified from almost all ages from a 2-year-old boy up to a 88-year-old woman and most prominently in 15-29 age group (37%, 74/198) followed by 30-44 age group (34.8%, 69/198 ) from 15 of Mongolia's 21 provinces, while cattle cysticerci were found from 12 provinces. The highest proportion of taeniasis patients was in Ulaanbaatar, the capital of Mongolia.


Asunto(s)
Cisticercosis/epidemiología , ADN de Helmintos/genética , ADN Mitocondrial/genética , Taenia saginata/genética , Teniasis/epidemiología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Animales , Bovinos/parasitología , Niño , Preescolar , Cisticercosis/parasitología , Heces/parasitología , Femenino , Geografía , Humanos , Masculino , Carne/parasitología , Persona de Mediana Edad , Mitocondrias/genética , Mongolia/epidemiología , Enfermedades Desatendidas/epidemiología , Técnicas de Amplificación de Ácido Nucleico/veterinaria , Encuestas y Cuestionarios , Taenia solium/genética , Teniasis/parasitología , Adulto Joven
10.
J Clin Biochem Nutr ; 55(1): 32-9, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25120277

RESUMEN

Reverse cholesterol transport (RCT) is a mechanism critical to the anti-atherogenic property of HDL. Although citrulline contributes to the amelioration of atherosclerosis via endothelial nitric oxide production, it remains unclear whether it affects RCT. This study was undertaken to clarify the effects of citrulline on expressions of specific transporters such as ATP binding cassette transporters (ABC)A1 and ABCG1, and the cholesterol efflux from macrophages to apolipoprotein (apo) A-I or HDL in vitro and ex vivo. Citrulline increased ABCA1 and ABCG1 mRNA and protein levels in THP-1 macrophages, translating into enhanced apoA-I- and HDL-mediated cholesterol efflux. In the human crossover study, 8 healthy male volunteers (age 30-49 years) consumed either 3.2 g/day citrulline or placebo for 1 week. Citrulline consumption brought about significant increases in plasma levels of citrulline and arginine. Supporting the in vitro data, monocyte-derived macrophages (MDM) differentiated under autologous post-citrulline sera demonstrated enhancement of both apoA-I- and HDL-mediated cholesterol efflux through increased ABCA1 and ABCG1 expressions, compared to MDM differentiated under pre-citrulline sera. However, the placebo did not modulate these parameters. Therefore, in addition to improving endothelium function, citrulline might have an anti-atherogenic property by increasing RCT of HDL.

11.
Atherosclerosis ; : 117578, 2024 May 12.
Artículo en Inglés | MEDLINE | ID: mdl-38797615

RESUMEN

BACKGROUND AND AIMS: High density lipoprotein (HDL) exerts an anti-atherosclerotic effect via reverse cholesterol transport (RCT). Several phases of RCT are transcriptionally controlled by Liver X receptors (Lxrs). Although macrophage Lxrs reportedly promote RCT, it is still uncertain whether hepatic Lxrs affect RCT in vivo. METHODS: To inhibit Lxr-dependent pathways in mouse livers, we performed hepatic overexpression of sulfotransferase family cytosolic 2B member 1 (Sult2b1) using adenoviral vector (Ad-Sult2b1). Ad-Sult2b1 or the control virus was intravenously injected into wild type mice and Lxrα/ß double knockout mice, under a normal or high-cholesterol diet. A macrophage RCT assay and an HDL kinetic study were performed. RESULTS: Hepatic Sult2b1 overexpression resulted in reduced expression of Lxr-target genes - ATP-binding cassette transporter G5/G8, cholesterol 7α hydroxylase and Lxrα itself - respectively reducing or increasing cholesterol levels in HDL and apolipoprotein B-containing lipoproteins (apoB-L). A macrophage RCT assay revealed that Sult2b1 overexpression inhibited fecal excretion of macrophage-derived 3H-cholesterol only under a high-cholesterol diet. In an HDL kinetic study, Ad-Sult2b1 promoted catabolism/hepatic uptake of HDL-derived cholesterol, thereby reducing fecal excretion. Finally, in Lxrα/ß double knockout mice, hepatic Sult2b1 overexpression increased apoB-L levels, but there were no differences in HDL levels or RCT compared to the control, indicating that Sult2b1-mediated effects on HDL/RCT and apoB-L were distinct: the former was Lxr-dependent, but not the latter. CONCLUSIONS: Hepatic Lxr inhibition negatively regulates circulating HDL levels and RCT by reducing Lxr-target gene expression.

12.
Biochim Biophys Acta ; 1821(4): 561-72, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22353356

RESUMEN

ABC transporter G1 (ABCG1) plays a pivotal role in HDL-mediated cholesterol efflux and atherogenesis. We investigated whether, and how, retinoic acid receptors (RARs) regulate ABCG1 expression in macrophages. All-trans retinoic acid (ATRA), an RAR ligand, increased ABCG1 protein levels and apoA-I/HDL-mediated cholesterol efflux from the macrophages. Both ATRA and other RAR agonists, TTNPB and Am580, increased major transcripts driven by promoter B upstream of exon 5, though minor transcripts driven by promoter A upstream of exon 1 were only increased by ATRA. The stimulatory effects of ATRA on ABCG1 expression were completely abolished in the presence of RAR/RXR antagonists but were only partially canceled in the presence of an LXR antagonist. Adenovirus with overexpressed oxysterol sulfotransferase abolished the LXR pathway, as previously reported, and ATRA-responsiveness in ABCA1/ABCG1 expressions were respectively attenuated by 38 and 22% compared to the control virus. Promoter assays revealed that ABCG1 levels were regulated more by promoter B than promoter A, and ATRA activated promoter B in a liver X receptor-responsive element (LXRE)-dependent manner. Further, LXRE-B in intron 7, but not LXRE-A in intron 5, enhanced ATRA responsiveness under overexpression of all RAR isoforms-RARα/ß/γ. In contrast, the activation of promoter B by TTNPB depended on LXRE-B and RARα, but not on RARß/γ. Finally, chromatin immunoprecipitation and gel-shift assays revealed a specific and direct repeat 4-dependent binding of RARα to LXRE-B. In conclusion, RAR ligands increase ABCA1/G1 expression and apoA-I/HDL-mediated cholesterol efflux from macrophages, and modulate ABCG1 promoter activity via LXRE-dependent mechanisms.


Asunto(s)
Transportadoras de Casetes de Unión a ATP/metabolismo , Macrófagos/efectos de los fármacos , Receptores de Ácido Retinoico/agonistas , Tretinoina/farmacología , Transportador 1 de Casete de Unión a ATP , Transportador de Casetes de Unión a ATP, Subfamilia G, Miembro 1 , Transportadoras de Casetes de Unión a ATP/genética , Animales , Benzoatos/farmacología , Transporte Biológico/efectos de los fármacos , Western Blotting , Células COS , Línea Celular , Chlorocebus aethiops , Colesterol/metabolismo , Regulación de la Expresión Génica/efectos de los fármacos , Células HEK293 , Humanos , Receptores X del Hígado , Macrófagos/citología , Macrófagos/metabolismo , Modelos Genéticos , Receptores Nucleares Huérfanos/agonistas , Receptores Nucleares Huérfanos/genética , Receptores Nucleares Huérfanos/metabolismo , Regiones Promotoras Genéticas/genética , Unión Proteica/efectos de los fármacos , Receptores de Ácido Retinoico/genética , Receptores de Ácido Retinoico/metabolismo , Elementos de Respuesta/genética , Receptores X Retinoide/agonistas , Receptores X Retinoide/genética , Receptores X Retinoide/metabolismo , Retinoides/farmacología , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Transducción de Señal/efectos de los fármacos , Tetrahidronaftalenos/farmacología
14.
Parasitology ; 140(13): 1589-94, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23790268

RESUMEN

SUMMARY Cysticercosis caused by infection with the larval stage of Taenia solium is an important cause of neurological disease worldwide and immunodiagnosis is important for the control and elimination of cysticercosis. In the present study, we established a simple and reliable preparation of immunodiagnostic low-molecular-weight antigens (LMWAgs) from T. solium cyst fluids by a cation-exchange chromatography (CEC). Banding patterns of LMWAgs on SDS-PAGE were different between isolates from Ecuador and China. All cysticercosis patient sera and some echinococcosis patient sera recognized both LMWAgs by enzyme-linked immunosorbent assay (ELISA), but sera from healthy persons were not positive. There was no statistical difference in immunodiagnostic performance of LMWAgs prepared from different geographical isolates. These results indicated that these novel immunodiagnostic antigen preparations could contribute the control and prevention of cysticercosis in endemic areas, especially developing countries.


Asunto(s)
Antígenos Helmínticos/análisis , Cisticercosis/diagnóstico , Cisticercosis/veterinaria , Inmunoensayo , Enfermedades de los Porcinos/diagnóstico , Taenia solium/aislamiento & purificación , Animales , China , Cromatografía por Intercambio Iónico , Cisticercosis/inmunología , Cisticercosis/parasitología , Países en Desarrollo , Ecuador , Humanos , Larva/química , Larva/inmunología , Peso Molecular , Juego de Reactivos para Diagnóstico , Porcinos , Enfermedades de los Porcinos/inmunología , Enfermedades de los Porcinos/parasitología , Taenia solium/química , Taenia solium/inmunología
15.
Parasitology ; 140(13): 1648-54, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23953219

RESUMEN

The small intestines of 420 wild canids (111 corsac foxes, 191 red foxes and 118 wolves) from Mongolia, were examined for adult worms of the genus Echinococcus. The Mongolian genotype of Echinococcus multilocularis was found in fifteen red foxes and four wolves, whereas two genotypes (G6/7 and G10) of Echinococcus canadensis were found in two and three wolves, respectively. No adult Echinococcus worms were found in the corsac foxes examined. The genotypes of E. multilocularis and E. canadensis are discussed in terms of host specificity and distribution in Mongolia. The importance of wolves in the completion of the life cycle of Echinococcus spp. is also discussed.


Asunto(s)
ADN de Helmintos/genética , ADN Mitocondrial/genética , Equinococosis/veterinaria , Echinococcus/genética , Complejo IV de Transporte de Electrones/genética , Zorros/parasitología , Filogenia , Lobos/parasitología , Animales , ADN de Helmintos/clasificación , ADN Mitocondrial/clasificación , Equinococosis/epidemiología , Equinococosis/parasitología , Echinococcus/clasificación , Complejo IV de Transporte de Electrones/clasificación , Heces/parasitología , Genoma Mitocondrial , Genotipo , Especificidad del Huésped , Intestino Delgado/parasitología , Epidemiología Molecular , Mongolia/epidemiología , Especificidad de la Especie
16.
Zoolog Sci ; 30(6): 461-8, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23721470

RESUMEN

We examined gill morphology and ventilatory function in the carpet shark family Parascylliidae using 14 preserved specimens of Parascyllium ferrugineum, P. variolatum, P. collare and Cirrhoscyllium japonicum, and two live specimens of P. ferrugineum and P. variolatum. Morphological examinations revealed eight morphological characteristics related to the fifth gill, based on comparisons with other elasmobranchs, viz. large fifth gill slit without gill filaments, anatomical modifications in the fourth ceratobranchial cartilage and coraco-branchialis muscle, and the hypaxialis muscle associated with the fifth gill arch. Ventilation examinations using dyed seawater and prey items showed different water flows through the gill slits for respiration and prey-capture actions. For respiration, water sucked into the mouth was expelled equally through the first to fourth gill slits via a "double-pump" action, there being no involvement of the fifth gill slit. In prey-capture, however, water sucked into the mouth was discharged only via the widely opened fifth gill slit. This form of water flow is similar to that in other benthic suction-feeding sharks (e.g., Chiloscyllium plagiosum), except for the active water discharge by wide expansion and contraction of the fifth parabranchial cavity. The latter is dependent upon the morphological modifications of the fourth and fifth gill arches, derived phylogenetically as a mechanistic suction specialization in Parascylliidae.


Asunto(s)
Branquias/anatomía & histología , Branquias/fisiología , Tiburones/anatomía & histología , Tiburones/fisiología , Animales , Consumo de Oxígeno/fisiología
17.
Exp Parasitol ; 135(2): 320-4, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23916766

RESUMEN

We herein describe the establishment of single hepatic lesions of Echinococcus multilocularis in rats. A 3mm incision was made on the liver with a surgical knife, and one small round vesicle of E. multilocularis (between 1 × 1 mm and <2 × 2 mm in diameter) was transplanted into the incision and covered with absorbable hemostat gauze. The presence and growth of the transplanted vesicle was monitored for 12 weeks using magnetic resonance imaging (MRI). Hepatic lesions, the metacestode of this parasite were confirmed in 12 of 17 infected rats (70.6%) by MRI and macroscopic examinations. The average size of the metacestodes with brood capsules at 12 weeks after the experimental transplantation of a single vesicle was 6.1 ± 2.5 mm × 4.4 ± 1.5mm. The smallest size of the metacestodes detected by MRI was approximately 3 × 3 mm. This new approach of establishing single hepatic metacestodes of E. multilocularis in experimental animals is expected to be useful for analyzing the immune-pathological mechanisms of hepatic AE.


Asunto(s)
Modelos Animales de Enfermedad , Equinococosis Hepática/parasitología , Echinococcus multilocularis , Hígado/parasitología , Animales , Femenino , Imagen por Resonancia Magnética , Ratas , Organismos Libres de Patógenos Específicos
18.
Zootaxa ; 3752: 130-71, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-25229112

RESUMEN

Sharks of the genus Apristurus from Taiwanese waters are reviewed for the first time, and incorrect scientific names and wrong taxonomic information given in the literature are corrected. After extensive examination of specimens deposited in various museums, universities and fisheries institutions in Taiwan, Japan and China, the following five species are recognized from Taiwanese waters: Apristurus herklotsi (Fowler, 1934), A. longicephalus Nakaya, 1975, A. gibbosus Meng, Chu & Li, 1985, A. macrostomus Chu, Meng & Li, 1985, and A. platyrhynchus (Tanaka, 1909). Apristurus herklotsi, A. longicephalus, A. gibbosus and A. macrostomus are reported from Taiwanese waters for the first time, and the presence of A. platyrhynchus is formally recognized based on a single voucher specimen. Each species is fully described, and a key to the species of Apristurus in Taiwanese waters is provided. Morphological and biological information of each species is also provided.


Asunto(s)
Tiburones/anatomía & histología , Tiburones/clasificación , Animales , Demografía , Femenino , Masculino , Océano Pacífico , Tiburones/fisiología , Especificidad de la Especie , Taiwán
19.
Zootaxa ; 3752: 101-29, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-25229111

RESUMEN

Sharks of the genus Cephaloscyllium from Taiwan were reviewed. After extensive survey of the specimens deposited in useums, universities and fisheries institutions in Taiwan and Japan, the following four species were recognized as valid n Taiwanese waters: C. umbratile Jordan & Fowler, 1903, C. fasciatum Chan, 1966, C. sarawakensis Yano, Ahmad & Gambang, 2005, and C. formosanum Teng, 1962. Cephaloscyllium formosanum is resurrected herein. Four species (C. circulopullum Yano, Ahmad & Gambang, 2005, C. parvum Inoue & Nakaya, 2006, C. pardelotum Schaaf-da Silva & Ebert, 2008, C. maculatum Schaaf-da Silva & Ebert, 2008) are concluded to be junior synonyms. The four valid species here recognized are fully described, and a key to Taiwanese species is provided. The original description of C. formosanum was translated into English from Japanese and is included as an Appendix.


Asunto(s)
Tiburones/anatomía & histología , Tiburones/clasificación , Animales , Demografía , Femenino , Masculino , Océano Pacífico , Tiburones/fisiología , Especificidad de la Especie , Taiwán
20.
Zootaxa ; 3752: 279-386, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-25229120

RESUMEN

An annotated checklist of chondrichthyan fishes (sharks, batoids, and chimaeras) occurring in Taiwanese waters is presented. The checklist is the result of a biodiversity workshop held in Mach 2012 as well as on-going systematic revisions by the authors. The chondrichthyan fauna of Taiwan is one of the richest in the world with the number of species totaling 181, comprising 52 families and 98 genera. It includes 31 families, 64 genera, and 119 species of sharks, 19 families, 31 genera, and 58 species of batoids, and 2 families, 3 genera, and 4 species of chimaeras. The most species-rich families are the Carcharhinidae with 22 species followed by the Scyliorhinidae with 17. The most species-rich batoid families are the Dasyatidae with 11 species and and the Rajidae with 10. Verified voucher material is provided for each species where available and potential taxonomic issues are high-lighted when applicable. This represents the first detailed, evidence-based checklist of chondrichthyans from Taiwanese waters in over 40 years.


Asunto(s)
Elasmobranquios/clasificación , Elasmobranquios/fisiología , Animales , Demografía , Femenino , Masculino , Océano Pacífico , Especificidad de la Especie , Taiwán
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