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1.
Artículo en Inglés | MEDLINE | ID: mdl-37008716

RESUMEN

Hemichordate enteropneust worms regenerate extensively in a manner that resembles the regeneration for which planaria and hydra are well known. Although hemichordates are often classified as an extant phylogenetic group that may hold ancestral deuterostome body plans at the base of the deuterostome evolutionary line leading to chordates, mammals, and humans, extensive regeneration is not known in any of these more advanced groups. Here we investigated whether hemichordates deploy functional homologs of canonical Yamanaka stem cell reprogramming factors, Oct4, Sox2, Nanog, and Klf4, as they regenerate. These reprogramming factors are not expressed during regeneration of limbs, fins, eyes or other structures that represent the best examples of regeneration in chordates. We first examined Ptychodera flava EST libraries and identified Pf-Pou3, Pf-SoxB1, Pf-Msxlx, and Pf-Klf1/2/4 as most closely related to the Yamanaka factors, respectively. In situ hybridization analyses revealed that all these homologs are expressed in a distinct manner during head regeneration. Furthermore, Pf-Pou3 partially rescued the loss of endogenous Oct4 in mouse embryonic stem cells in maintaining the pluripotency gene expression program. Based on these results, we propose that hemichordates may have co-opted these reprogramming factors for their extensive regeneration or that chordates may have lost the ability to mobilize these factors in response to damage. The robustness of these pluripotency gene circuits in the inner cell mass and in formation of induced pluripotent stem cells from mammalian somatic cells shows that these programs are intact in humans and other mammals and that these circuits may respond to as yet unknown gene regulatory signals, mobilizing full regeneration in hemichordates.

2.
Respir Investig ; 55(4): 270-275, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28705306

RESUMEN

BACKGROUND: Riociguat, the first approved drug for patients with chronic thromboembolic pulmonary hypertension (CTEPH), is a soluble guanylate cyclase (sGC) Stimulator. It directly stimulates sGC independently of nitric oxide (NO) and increases sGC sensitivity for NO. The safety and efficacy of transitioning from a phosphodiesterase 5 inhibitor (PDE5i) to riociguat is unknown. METHODS AND RESULTS: Twenty-three patients were prospectively enrolled: 8 symptomatic patients with inadequate clinical responses to PDE5i were changed to riociguat (transitioned group); 15 started riociguat anew (new or add-on group). We analyzed the change from baseline to 6-12 months of riociguat treatment for the 6-minute walk distance (6MWD), mean pulmonary arterial pressure (mPAP), pulmonary vascular resistance (PVR), cardiac index (CI), partial pressure of oxygen in arterial blood (PaO2), brain natriuretic peptide (BNP), World Health Organization (WHO) functional class, safety and adverse events. The mPAP, BNP and WHO functional class significantly improved in total. In the transitioned group, BNP significantly decreased by -116.5±188.6pg/ml (P=0.0156). The 6MWD, mPAP, PVR, CI, and PaO2 improved but not significantly. The baseline condition was significantly more severe in the transitioned than in the new or add-on group. No patients discontinued riociguat. Relatively rapid transitioning from PDE5i to riociguat was safe under careful observation. CONCLUSIONS: Transitioning to riociguat may be safe and effective in CTEPH patients with inadequate clinical responses to PDE5i.


Asunto(s)
Sustitución de Medicamentos , Hipertensión Pulmonar/tratamiento farmacológico , Inhibidores de Fosfodiesterasa 5/uso terapéutico , Embolia Pulmonar/tratamiento farmacológico , Pirazoles/uso terapéutico , Pirimidinas/uso terapéutico , Anciano , Presión Arterial , Enfermedad Crónica , Femenino , Humanos , Hipertensión Pulmonar/metabolismo , Hipertensión Pulmonar/fisiopatología , Masculino , Persona de Mediana Edad , Péptido Natriurético Encefálico/metabolismo , Consumo de Oxígeno , Presión Parcial , Arteria Pulmonar/fisiopatología , Embolia Pulmonar/metabolismo , Embolia Pulmonar/fisiopatología , Factores de Tiempo , Resistencia Vascular , Prueba de Paso
3.
Pulm Circ ; 7(3): 684-691, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28604280

RESUMEN

Patients with chronic thromboembolic pulmonary hypertension (CTEPH) require lifelong anticoagulation therapy. However, the bleeding risk and recurrence of venous thromboembolism (VTE) in CTEPH patients who are administered warfarin have not been adequately evaluated. The purpose of this study was to evaluate the risk of clinically relevant bleeding, recurrent VTE, and clinical worsening in patients with CTEPH who were administered warfarin. The clinical records of 72 patients with CTEPH who regularly visited our institution and were administered warfarin were retrospectively reviewed between 1 January 2011 and 31 December 2015. We investigated the incidence of clinically relevant bleeding events, recurrent VTE, and hospitalization for the deterioration of pulmonary hypertension or right heart failure (RHF) during the observation period. The mean observation period for the 72 patients was 3.60 ± 1.60 person-years. Clinically relevant bleeding, RHF, and recurrent VTE occurred in 21 (29.2%), eight (11.1%), and three (4.2%) of 72 patients, respectively, and the incidence rates for these events were 8.1%/person-year, 3.1%/person-year, and 1.2%/person-year, respectively. The incidence rates for the major and non-major bleeding events were 5.0%/person-year and 3.9%/person-year, respectively. The incidence of clinically relevant bleeding events was 20.8%/person-year during medical treatment with a soluble guanylate cyclase stimulator. One of 35 patients (2.9%) during the post-pulmonary endarterectomy period experienced hemoptysis during observation period (> 6 months after pulmonary endarterectomy). No bleeding events occurred during the post-balloon pulmonary angioplasty period. In conclusion, warfarin effectively prevents VTE recurrence in CTEPH patients, but its effects may be associated with a considerable bleeding risk.

4.
Nature ; 527(7579): 459-65, 2015 Nov 26.
Artículo en Inglés | MEDLINE | ID: mdl-26580012

RESUMEN

Acorn worms, also known as enteropneust (literally, 'gut-breathing') hemichordates, are marine invertebrates that share features with echinoderms and chordates. Together, these three phyla comprise the deuterostomes. Here we report the draft genome sequences of two acorn worms, Saccoglossus kowalevskii and Ptychodera flava. By comparing them with diverse bilaterian genomes, we identify shared traits that were probably inherited from the last common deuterostome ancestor, and then explore evolutionary trajectories leading from this ancestor to hemichordates, echinoderms and chordates. The hemichordate genomes exhibit extensive conserved synteny with amphioxus and other bilaterians, and deeply conserved non-coding sequences that are candidates for conserved gene-regulatory elements. Notably, hemichordates possess a deuterostome-specific genomic cluster of four ordered transcription factor genes, the expression of which is associated with the development of pharyngeal 'gill' slits, the foremost morphological innovation of early deuterostomes, and is probably central to their filter-feeding lifestyle. Comparative analysis reveals numerous deuterostome-specific gene novelties, including genes found in deuterostomes and marine microbes, but not other animals. The putative functions of these genes can be linked to physiological, metabolic and developmental specializations of the filter-feeding ancestor.


Asunto(s)
Cordados no Vertebrados/genética , Evolución Molecular , Genoma/genética , Animales , Cordados no Vertebrados/clasificación , Secuencia Conservada/genética , Equinodermos/clasificación , Equinodermos/genética , Familia de Multigenes/genética , Filogenia , Transducción de Señal , Sintenía/genética , Factor de Crecimiento Transformador beta
5.
Kekkaku ; 90(9): 635-9, 2015 Sep.
Artículo en Japonés | MEDLINE | ID: mdl-26761996

RESUMEN

A 75-year-old woman was referred to our hospital after a health check-up disclosed abnormal shadows in the bilateral lungs. The patient was admitted to our hospital after being diagnosed with pulmonary tuberculosis. A physical examination showed a mass in the left inguinal area. Enhanced computed tomography revealed that the tuberculosis involved several regions including the lumber vertebrae, iliopsoas muscles, and left inguinal area. A therapeutic regimen consisting of INH, RFP, EB, and PZA was begun. Neuropathy in the lower extremities and dysuria indicated a spinal lesion, and spinal surgery was considered. However, the patient's history indicated that these symptoms were likely due to an iliopsoas abscess rather than a spinal lesion. This hypothesis was confirmed when the patient's symptoms improved with no sequelae after the abscess was drained. Our case demonstrates that spinal lesions as well as iliopsoas abscesses can cause neuropathy, and underscores the importance of obtaining a patient's history to correctly diagnose the disease and determine the appropriate treatment options.


Asunto(s)
Enfermedades del Sistema Nervioso Periférico/terapia , Absceso del Psoas/terapia , Tuberculosis Pulmonar , Tuberculosis de la Columna Vertebral/terapia , Anciano , Drenaje , Femenino , Humanos , Enfermedades del Sistema Nervioso Periférico/etiología , Absceso del Psoas/etiología , Tomografía Computarizada por Rayos X , Tuberculosis de la Columna Vertebral/complicaciones
6.
Zoolog Sci ; 31(7): 414-20, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25001912

RESUMEN

Recent investigations into the evolution of deuterostomes and the origin of chordates have paid considerable attention to hemichordates (acorn worms), as hemichordates and echinoderms are the closest chordate relatives. The present study prepared cDNA libraries from Ptychodera flava, to study expression and function of genes involved in development of the hemichordate body plan. Expressed sequence tag (EST) analyses of nine cDNA libraries yielded 18,832 cloned genes expressed in eggs, 18,739 in blastulae, 18,539 in gastrulae, 18,811 in larvae, 18,978 in juveniles, 11,802 in adult proboscis, 17,259 in stomochord, 11,886 in gills, and 11,580 in liver, respectively. A set of 34,159 uni-gene clones of P. flava was obtained. This cDNA resource will be valuable for studying temporal and spatial expression of acorn worm genes during development.


Asunto(s)
Cordados no Vertebrados/fisiología , ADN Complementario/metabolismo , Regulación de la Expresión Génica/fisiología , Animales , Clonación Molecular , ADN Complementario/genética , Etiquetas de Secuencia Expresada
7.
Kekkaku ; 89(11): 807-12, 2014 Nov.
Artículo en Japonés | MEDLINE | ID: mdl-25730949

RESUMEN

A 48-year-old woman, who had been suffering from systemic lupus erythematosus for one year and receiving steroid therapy, was admitted to our hospital because of pulmonary tuberculosis. The tuberculosis was treated with INH, RFP, EB, and PZA after having doubled the dose of steroid, but terminated three weeks later due to the appearance of erythema exsudativum multiforme. Treatment was resumed with PZA, SM, and LVFX after resolution of the eruption. However, the addition of INH to the regimen provoked a recurrence of the eruption, which progressed rapidly to toxic epidermal necrolysis (TEN). Steroid pulse therapy stopped progression of the TEN, and treatment for tuberculosis was resumed. Although the choice of drug was rendered difficult by other adverse reactions, the patient was able to complete her tuberculosis treatment with RFP, EB, and TH. INH was most likely to be the offending agent in this case. Eruptions induced by antitubercular drugs are often seen, but there are few reports of severe toxic epidermal necrolysis.


Asunto(s)
Antituberculosos/efectos adversos , Lupus Eritematoso Sistémico/complicaciones , Síndrome de Stevens-Johnson/tratamiento farmacológico , Antituberculosos/uso terapéutico , Combinación de Medicamentos , Femenino , Humanos , Persona de Mediana Edad , Tuberculosis Pulmonar/complicaciones , Tuberculosis Pulmonar/tratamiento farmacológico
8.
Nihon Kokyuki Gakkai Zasshi ; 49(11): 867-72, 2011 Nov.
Artículo en Japonés | MEDLINE | ID: mdl-22171493

RESUMEN

Klippel-Trenaunay-Weber syndrome (KTWS) is a rare congenital disorder characterized by varicose veins, cutaneous hemangiomas, hypertrophy of soft tissue and bone and arteriovenous malformations. We present a case of a 43-year-old man with KTWS. He experienced progressive pulmonary hypertension due to recurrent pulmonary embolism, which developed despite adequate anticoagulation. This case report suggests that patients with KTWS need more aggressive management and treatment of their thromboembolitic state and pulmonary hypertension.


Asunto(s)
Hipertensión Pulmonar/etiología , Síndrome de Klippel-Trenaunay-Weber/complicaciones , Adulto , Humanos , Masculino
9.
Zoolog Sci ; 27(2): 91-5, 2010 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-20141413

RESUMEN

When the body of P. flava is severed, the animal has the ability to regenerate its missing anterior or posterior as appropriate. We have focused on anterior regeneration when the head and branchial regions are severed from the body of the worm. After transection, the body wall contracts and heals closed in 2 to 3 days. By the third day a small blastema is evident at the point of closure. The blastema grows rapidly and begins the process of differentiating into a head with a proboscis and collar. At 5 days the blastema has increased greatly in size and differentiated into a central bulb, the forming proboscis, and two lateral crescents, the forming collar. Between 5 and 7 days a mouth opens ventral to the differentiating blastema. Over the next few days the lateral crescents extend to encircle the proboscis and mouth, making a fully formed collar. By 10 to 12 days a new head, sized to fit the worm's body, has grown attached to the severed site. At about this time the animal regains apparently normal burrowing behavior. After the head is formed, a second blastema-like area appears between the new head and the old body and a new branchial region is inserted by regeneration from this blastema over the next 2 to 3 weeks. The regenerating tissues are unpigmented and whitish such that in-situ hybridization can be used to study the expression of genes during the formation of new tissues.


Asunto(s)
Cordados no Vertebrados/fisiología , Regeneración/fisiología , Animales , Cordados no Vertebrados/ultraestructura
10.
Gastroenterology ; 135(2): 580-90, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18588891

RESUMEN

BACKGROUND & AIMS: The calcium channel voltage-dependent alpha2delta subunit consists of 4 genes, CACNA2D1 to CACNA2D4, of which CACNA2D2 and CACNA2D3 are located on 3p21.3 and 3p21.1, respectively. Here, we examined the relation between alpha2delta subunit gene alterations and gastric carcinogenesis. METHODS: The expression and methylation status of the alpha2delta subunit genes were analyzed by reverse transcription-polymerase chain reaction (RT-PCR) and methylation-specific PCR in gastric cancers (GCs). The effects of CACNA2D3 expression were examined by cell proliferation and adhesion assays, and they predicted target gene alterations. RESULTS: Aberrant methylation of CACNA2D1 and CACNA2D3 mostly corresponded to their expression status in GC cell lines. CACNA2D1/3 methylation was detected in 10 (12.5%) and 24 (30%) of the 80 GC cases, respectively, but no CACNA2D2 methylation was seen in 32 cases. CACNA2D3 methylation was more frequently found in diffuse type than in intestinal type (16/38 [42.1%] vs 8/42 [19.0%]; P = .025) GCs. Among the 53 patients with advanced GCs, patients with cancers showing CACNA2D3 methylation had a significantly shorter survival time than patients without this methylation (P = .003). Exogenous CACNA2D3 expression strongly inhibited cell growth and adhesion and up-regulated p21 and p27 expression in HEK-293T and NUGC4 cells. Inverse effects were seen by CACNA2D3 small interfering RNA treatment in the CACNA2D3-positive cell lines, indicating that CACNA2D3 may have tumor suppressive functions. CONCLUSIONS: Loss of CACNA2D3 expression through aberrant promoter hypermethylation may contribute to gastric carcinogenesis, and CACNA2D3 methylation is a useful prognostic marker for patients with advanced GC.


Asunto(s)
Canales de Calcio/genética , Metilación de ADN , Regulación Neoplásica de la Expresión Génica , Silenciador del Gen , Genes Supresores de Tumor , Neoplasias Gástricas/genética , Anciano , Calcio/metabolismo , Canales de Calcio/metabolismo , Adhesión Celular , Línea Celular Tumoral , Proliferación Celular , Islas de CpG , Inhibidor p27 de las Quinasas Dependientes de la Ciclina/metabolismo , Citosol/metabolismo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Regiones Promotoras Genéticas , Interferencia de ARN , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/mortalidad , Neoplasias Gástricas/patología , Análisis de Supervivencia , Factores de Tiempo , Transfección , Quinasas p21 Activadas/metabolismo
11.
Biochem Pharmacol ; 75(5): 1014-26, 2008 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-18177630

RESUMEN

Four pseudo-symmetrical tamoxifen derivatives, RID-B (13), RID-C (14), RID-D (15), and bis(dimethylaminophenetole) (16), were synthesized via the novel three-component coupling reaction, and the structure-activity relationships of these pseudo-symmetrical tamoxifen derivatives were examined. It was discovered that 13 and 16 strongly inhibit the viability of the HL-60 human acute promyelocytic leukemia cell line, whereas 14 possesses a medium activity against the same cell line and 15 has no effect on the cell viability. The global anti-tumor activity of 13-16 against a variety of human cancer cells was assessed using a panel of 39 human cancer cell lines (JFCR 39), and it was shown that RID-B (13) strongly inhibited the growth of several cancer cell lines at concentrations of less than 1 microM (at 0.38 microM for SF-539 [central nervous system], at 0.58 microM for HT-29 [colon], at 0.20 microM for DMS114 [lung], at 0.21 microM for LOX-IMVI [melanoma], and at 0.23 microM for MKN74 [stomach]).


Asunto(s)
Antineoplásicos/farmacología , Tamoxifeno/análogos & derivados , Tamoxifeno/farmacología , Antineoplásicos/síntesis química , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Células HL-60 , Humanos , Estructura Molecular , Tamoxifeno/síntesis química
12.
Chem Asian J ; 3(2): 462-72, 2008 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-18203212

RESUMEN

We have developed effective methods for the total synthesis of 2-hydroxytetracosanolide and 2-hydroxy-24-oxooctacosanolide, the defensive salivary secretions of termites. The former natural product isolated from Armitermes neotenicus, a species of termite that inhabits Guyana, contains a 25-membered lactone backbone, and the latter, extracted from Pseudacanthoterme springer, an African termite, includes a 29-membered lactone moiety. The key cyclization to produce the 25- or 29-membered lactone core is performed by using 2-methyl-6-nitrobenzoic anhydride (MNBA) with a stoichiometric amount of 4-(dimethylamino)pyridine (DMAP) or a catalytic amount of 4-(dimethylamino)pyridine N-oxide (DMAPO).


Asunto(s)
Macrólidos/síntesis química , Benzoatos/química , Catálisis , Cobre/química , Macrólidos/química , Estructura Molecular
13.
Cancer Sci ; 99(3): 608-14, 2008 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-18167132

RESUMEN

Tamoxifen is an antagonist of estrogen receptor, which is used widely as an estrogen receptor-positive breast cancer drug that blocks growth signals and provokes apoptosis. However, recent studies have revealed that tamoxifen induces apoptosis even in estrogen receptor-negative cells. In the present study, we synthesized several tamoxifen derivatives to augment the apoptosis-inducing effect of tamoxifen and evaluated the apoptosis-inducing pathway. The estrogen receptor-positive human leukemia cell line HL-60 and estrogen receptor-negative human leukemia cell line Jurkat were treated with tamoxifen and synthesized tamoxifen derivatives, and thereafter subjected to cell viability-detection assays. Tamoxifen derivatives, as well as the lead compound tamoxifen, decreased the cell viability despite the expression of estrogen receptor. Among all of the synthesized tamoxifen derivatives, ridaifen-B had more potent cancer cell-damaging activity than tamoxifen. Ridaifen-B fragmented Jurkat cell DNA and activated caspases, suggesting that the ridaifen-B-induced apoptosis pathway is estrogen receptor independent. Moreover, mitochondrial involvement during ridaifen-B-induced apoptosis was estimated. Ridaifen-B significantly reduced mitochondrial membrane potential, and overexpression of Bcl-2 inhibited ridaifen-B-induced apoptosis. These results suggest that the induction of apoptosis by ridaifen-B, a novel tamoxifen derivative, is dependent on mitochondrial perturbation without estrogen receptor involvement.


Asunto(s)
Antineoplásicos Hormonales/farmacología , Apoptosis , Mitocondrias/efectos de los fármacos , Pirrolidinas/farmacología , Tamoxifeno/análogos & derivados , Antineoplásicos Hormonales/química , Línea Celular Tumoral , Relación Dosis-Respuesta a Droga , Humanos , Células Jurkat , Mitocondrias/metabolismo , Pirrolidinas/síntesis química , Especies Reactivas de Oxígeno/metabolismo , Receptores de Estrógenos/metabolismo , Linfocitos T Colaboradores-Inductores/efectos de los fármacos , Tamoxifeno/síntesis química , Tamoxifeno/farmacología
14.
Bioorg Med Chem ; 15(24): 7599-617, 2007 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-17904372

RESUMEN

Two new synthetic pathways to the anti-cancer agent tamoxifen and its derivatives were developed. The first route involved the aldol reaction of benzyl phenyl ketone with acetaldehyde followed by Friedel-Crafts substitution with anisole in the presence of Cl(2)Si(OTf)(2) to produce 1,1,2-triaryl-3-acetoxybutane, a precursor of the tamoxifen derivatives. The second one utilized the novel three-component coupling reaction among aromatic aldehydes, cinnamyltrimethylsilane, and aromatic nucleophiles using HfCl(4) as a Lewis acid catalyst to produce 3,4,4-triarylbutene, that is also a valuable intermediate of the tamoxifen derivatives. The former strategy requires a total of 10 steps from the aldol formation to the final conversion to tamoxifen, whereas the latter needs only three or four steps to produce tamoxifen and droloxifene including the installation of the side-chain moiety and the base-induced double-bond migration to form the tetra-substituted olefin structure. This synthetic strategy seems to serve as a new and practical pathway to prepare not only the tamoxifen derivatives but also the other SERMs (selective estrogen receptor modulators) including estrogen-dependent breast cancer and osteoporosis agents.


Asunto(s)
Aldehídos/química , Aminoácidos Aromáticos/química , Antineoplásicos/síntesis química , Cinamatos/química , Éteres Fenílicos/química , Moduladores Selectivos de los Receptores de Estrógeno/síntesis química , Tamoxifeno/síntesis química , Compuestos de Trimetilsililo/química , Antineoplásicos/química , Antineoplásicos/farmacología , Línea Celular Tumoral , Humanos , Estructura Molecular , Moduladores Selectivos de los Receptores de Estrógeno/química , Moduladores Selectivos de los Receptores de Estrógeno/farmacología , Tamoxifeno/química , Tamoxifeno/farmacología , Factores de Tiempo
15.
Nat Protoc ; 2(10): 2312-7, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17947971

RESUMEN

This protocol describes a procedure for the synthesis of a 29-membered macrolactone. The facile mixed-anhydride method is very effective for the preparation of carboxylic esters and lactones using substituted benzoic anhydrides by the promotion of Lewis acid or basic catalysts under mild reaction conditions. Owing to the reaction rapidly proceeding to produce the monomeric compounds with high chemoselectivity, the protocol is quite powerful for the synthesis of not only the giant-sized lactones but also the highly strained cyclic compounds such as medium-sized lactones. The remarkable efficiency of the lactonizations promoted by the substituted benzoic anhydrides has been already shown in the synthesis of many natural complex molecules. It takes approximately 19 h to complete the protocol: 0.5 h to set up the reaction, 13.5 h for the reaction and 5 h for isolation and purification.


Asunto(s)
Benzoatos/química , Lactonas/síntesis química , Química Orgánica/métodos , Lactonas/química
16.
Zoolog Sci ; 24(7): 648-55, 2007 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-17824772

RESUMEN

DNA methylation is an important epigenetic factor that participates in silencing genes. Genomic approaches to studying DNA methylation promise to be particularly fruitful, since DNA methylation is involved in global control of gene expression in many organisms. With its draft genome completed and a large quantity of available cDNA data, Ciona intestinalis is newly emerging as an invaluable model organism for investigating genome-wide gene expression and function. Here we examine the effects of 5-aza-2'-deoxycytidine (5-aza-CdR), a chemical that blocks CpG methylation, on the gene expression profile of early C. intestinalis embryos, using oligonucleotide-based microarray analysis. Embryos treated with 5-aza-CdR show delayed gastrulation and are developmentally arrested at the neurula stage. They subsequently lose cellular adhesion and finally die. Apoptosis was not detected in these embryos by TUNEL staining at 12 h, indicating that the defects observed did not result from 5-aza-CdR-induced apoptosis. Gene expression profiles of 12-h-old 5-aza-CdR-treated embryos compared to wild-type revealed 91 upregulated genes and 168 downregulated genes. Although nearly half of these encoded proteins with unknown functions, several encoded cell-signaling molecules and transcription factors. In addition, genes associated with the stress response and cell defense were upregulated, whereas genes involved in cell adhesion were downregulated.


Asunto(s)
Azacitidina/análogos & derivados , Ciona intestinalis/efectos de los fármacos , Inhibidores Enzimáticos/farmacología , Regulación del Desarrollo de la Expresión Génica/efectos de los fármacos , Análisis de Secuencia por Matrices de Oligonucleótidos/veterinaria , Animales , Azacitidina/farmacología , Ciona intestinalis/embriología , Ciona intestinalis/genética , Decitabina , Embrión no Mamífero/efectos de los fármacos , Perfilación de la Expresión Génica/veterinaria , Regulación del Desarrollo de la Expresión Génica/fisiología
17.
Bioorg Med Chem Lett ; 17(9): 2421-4, 2007 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-17346960

RESUMEN

Three new pseudo-symmetrical tamoxifen derivatives, RID-B (15), C (16), and D (17), were synthesized via the novel three-component coupling reaction, and the structure-activity relationships of the pseudo-symmetrical tamoxifen derivatives were examined. It was discovered that 15 strongly inhibits the viability of HL-60 human acute promyelocytic leukemia, whereas 16 possesses medium activity against the cell line and 17 has no effect on the cell viability. The agarose gel electrophoresis for DNA cleavage showed the cell death might be induced by apoptosis.


Asunto(s)
Antineoplásicos/síntesis química , Química Farmacéutica/métodos , Tamoxifeno/análogos & derivados , Tamoxifeno/síntesis química , Antineoplásicos/farmacología , Muerte Celular , Supervivencia Celular/efectos de los fármacos , Diseño de Fármacos , Evaluación Preclínica de Medicamentos , Células HL-60 , Humanos , Modelos Químicos , Conformación Molecular , Relación Estructura-Actividad , Tamoxifeno/farmacología , Factores de Tiempo
18.
Org Lett ; 8(21): 4955-8, 2006 Oct 12.
Artículo en Inglés | MEDLINE | ID: mdl-17020345

RESUMEN

[structure: see text] An effective method for the total synthesis of 2-hydroxy-24-oxooctacosanolide, a defensive salivary secretion of the African termite Pseudacanthotermes spiniger, has been developed. The key lactonization to form a 29-membered ring lactone core is performed using 2-methyl-6-nitrobenzoic anhydride with a catalytic amount of 4-(dimethylamino)pyridine N-oxide.


Asunto(s)
Lactonas/química , Macrólidos/síntesis química , Animales , Isópteros/química , Macrólidos/química , Estructura Molecular , Estereoisomerismo
19.
Bioorg Med Chem Lett ; 15(10): 2587-90, 2005 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-15863322

RESUMEN

Lambertellol C (1), a labile biosynthetic congener of lambertellols A and B, was isolated from a fermentation broth of Lambertella sp. 1346 based on the diagnostic isotope patterns in the mass spectrum of a highly labeled sample. The CD spectrum of 1 indicated that this lambertellol analogue exists as a racemate. The mechanism for this racemization is discussed.


Asunto(s)
Naftalenos/química , Naftalenos/farmacología , Compuestos de Espiro/química , Compuestos de Espiro/farmacología , Cromatografía Líquida de Alta Presión , Fermentación , Naftalenos/aislamiento & purificación , Espectrometría de Masa por Ionización de Electrospray , Espectrofotometría Ultravioleta , Compuestos de Espiro/aislamiento & purificación
20.
Bioorg Med Chem Lett ; 15(10): 2591-4, 2005 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-15863323

RESUMEN

A method for the sensitive analysis of the incorporation level of labeled acetate was developed. This method allowed for the optimization of the conditions for lambertellin with up to 48% average incorporation of labeled acetate.


Asunto(s)
Espectrometría de Masas/métodos , Naftalenos/química , Compuestos de Espiro/química , Marcaje Isotópico , Espectroscopía de Resonancia Magnética
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