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2.
J Hum Hypertens ; 30(6): 379-85, 2016 06.
Artículo en Inglés | MEDLINE | ID: mdl-26538381

RESUMEN

Primary aldosteronism due to unilateral aldosterone-producing adenoma (APA) is a surgically curable form of hypertension. Bilateral APA can also be surgically curable in theory but few successful cases can be found in the literature. It has been reported that even using successful adrenal venous sampling (AVS) via bilateral adrenal central veins, it is extremely difficult to differentiate bilateral APA from bilateral idiopathic hyperaldosteronism (IHA) harbouring computed tomography (CT)-detectable bilateral adrenocortical nodules. We report a case of bilateral APA diagnosed by segmental AVS (S-AVS) and blood sampling via intra-adrenal first-degree tributary veins to localize the sites of intra-adrenal hormone production. A 36-year-old man with marked long-standing hypertension was referred to us with a clinical diagnosis of bilateral APA. He had typical clinical and laboratory profiles of marked hypertension, hypokalaemia, elevated plasma aldosterone concentration (PAC) of 45.1 ng dl(-1) and aldosterone renin activity ratio of 90.2 (ng dl(-1) per ng ml(-1 )h(-1)), which was still high after 50 mg-captopril loading. CT revealed bilateral adrenocortical tumours of 10 and 12 mm in diameter on the right and left sides, respectively. S-AVS confirmed excess aldosterone secretion from a tumour segment vein and suppressed secretion from a non-tumour segment vein bilaterally, leading to the diagnosis of bilateral APA. The patient underwent simultaneous bilateral sparing adrenalectomy. Histopathological analysis of the resected adrenals together with decreased blood pressure and PAC of 5.2 ng dl(-1) confirmed the removal of bilateral APA. S-AVS was reliable to differentiate bilateral APA from IHA by direct evaluation of intra-adrenal hormone production.


Asunto(s)
Neoplasias de la Corteza Suprarrenal/diagnóstico , Neoplasias de la Corteza Suprarrenal/cirugía , Adrenalectomía/métodos , Adenoma Corticosuprarrenal/diagnóstico , Adenoma Corticosuprarrenal/cirugía , Aldosterona/sangre , Biomarcadores de Tumor/sangre , Recolección de Muestras de Sangre/métodos , Tratamientos Conservadores del Órgano , Neoplasias de la Corteza Suprarrenal/sangre , Neoplasias de la Corteza Suprarrenal/metabolismo , Adenoma Corticosuprarrenal/sangre , Adenoma Corticosuprarrenal/metabolismo , Adulto , Aldosterona/metabolismo , Biomarcadores de Tumor/metabolismo , Biopsia , Diagnóstico Diferencial , Humanos , Inmunohistoquímica , Masculino , Valor Predictivo de las Pruebas , Tomografía Computarizada por Rayos X , Resultado del Tratamiento , Venas
3.
Kyobu Geka ; 62(5): 358-61, 2009 May.
Artículo en Japonés | MEDLINE | ID: mdl-19425373

RESUMEN

Video-assisted thoracoscopic resection for mediastinal mature teratoma is sometimes converted to open thoracotomy. Because it has rich components including pancreatic tissue and dense adhesion, even when it is asymptomatic. Prior to thoracoscopic resection, extraction of the cystic components with the aid of a 20 Fr tube can provide a wide thoracoscopic view leading to easier complete removal. Between October 1998 and June 2008, 6 patients (1 man and 5 women) with benign mediastinal mature teratoma underwent the thoracoscopic operations. The average age was 36.3 (range, 24-54). The mean diameter was 9.0 cm (range, 5-11 cm). The mean operation time was 143 minutes and the mean blood loss was 103 ml. Neither complications nor tumor recurrences developed during the mean follow-up period of 3.4 years. The presented thoracoscopic surgery for benign mature teratoma is a feasible procedure.


Asunto(s)
Neoplasias del Mediastino/cirugía , Teratoma/cirugía , Cirugía Torácica Asistida por Video , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad
4.
J Phys Condens Matter ; 21(49): 495502, 2009 Dec 02.
Artículo en Inglés | MEDLINE | ID: mdl-21836198

RESUMEN

We studied the effect of Al doping in Zn(0.94)Co(0.05)Al(0.01)O nano-powders from the electronic structure point of view by applying x-ray absorption spectroscopy and resonant inelastic x-ray scattering at the oxygen K- and Co L-edges. The intensity of the pre-edge structure of the O-K XAS spectra is enhanced following the introduction of the Al defect. Multiple scattering calculations demonstrate it can be accounted for by the gain of the hybridization strength between O 2p and Al 3p (and/or Co 3d) states. The consensus on the hybridization strength is reached by combining Co-L XAS and RIXS investigations and multiplet calculations. It reveals different spatial substitutions of Al doping can alter the number of shared oxygen atoms between the Co and Al tetrahedrons. These shared ligands are responsible for the Al 3p and Co 3d state hybridization strength as well as the ferromagnetism of the ground state. The magnetic difference is better understood to be governed by various shared oxygen atoms rather than the distance between the Al defect and Co impurities.

5.
Kyobu Geka ; 61(11): 934-8, 2008 Oct.
Artículo en Japonés | MEDLINE | ID: mdl-18939428

RESUMEN

We retrospectively evaluated the surgical outcome after sleeve lobectomy and pneumonectomy with tracheobronchial reconstruction for lung cancer. From 1993 to 2008, 46 patients with primary lung cancer underwent these surgical procedures. Seventeen patients (37%) received induction therapy, 15 received chemotherapy, while chemoradiotherapy or radiotherapy alone were received by one patient each. Sleeve lobectomy without carinal resection was performed in 41 patients. Carinal resection with 2 sleeve pneumonectomies was performed in 5 patients. There were no operative deaths. Bronchopleural fistula occurred in one patient, who required completion pneumonectomy. One patient presented local mucosal necrosis in the anastomotic site and was managed conservatively. Two patients had bronchial strictures as late complications and successfully dilated by a balloon using bronchoscopy. Overall 5-year and 10-year survival rates were 54% and 48%, respectively. No recurrence developed at any anastomotic site. The results showed that sleeve lobectomy and pneumonectomy with tracheobronchial reconstruction can be performed with low mortality and bronchial anastomotic complication rates. As well, local control of the tumor was satisfactory.


Asunto(s)
Neoplasias Pulmonares/cirugía , Procedimientos de Cirugía Plástica , Procedimientos Quirúrgicos Torácicos , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neumonectomía , Procedimientos de Cirugía Plástica/mortalidad , Estudios Retrospectivos , Tasa de Supervivencia , Procedimientos Quirúrgicos Torácicos/mortalidad , Resultado del Tratamiento
6.
Kyobu Geka ; 61(11): 993-5, 2008 Oct.
Artículo en Japonés | MEDLINE | ID: mdl-18939440

RESUMEN

We report a rare case of atypical pulmonary carcinoid tumor accompanied by elevation of serum gastrin-releasing peptide precursor (ProGRP). A 55-year-old male presented to our hospital with a history of bloody sputum. The level of serum ProGRP was elevated to 781 pg/ml (normal < 46 pg/ml). Chest computed tomography (CT) revealed a solitary pulmonary tumor in the left lower lobe with sub-carinal lymph node enlargement. Transbronchial lung biopsy showed a pulmonary carcinoid, therefore left lower lobectomy with mediastinal lymph node dissection was performed. ProGRP decreased to normal level 1 month after operation. Histopathological diagnosis showed an atypical pulmonary carcinoid tumor.


Asunto(s)
Biomarcadores de Tumor/sangre , Tumor Carcinoide/diagnóstico , Neoplasias Pulmonares/diagnóstico , Fragmentos de Péptidos/sangre , Biopsia , Tumor Carcinoide/patología , Tumor Carcinoide/cirugía , Humanos , Neoplasias Pulmonares/patología , Neoplasias Pulmonares/cirugía , Escisión del Ganglio Linfático , Masculino , Persona de Mediana Edad , Neumonectomía , Proteínas Recombinantes/sangre , Resultado del Tratamiento
7.
J Dent Res ; 87(7): 676-81, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18573990

RESUMEN

In previous studies, human dental pulp stem cells (hDPSCs) were mainly isolated from adults. In this present study, we characterized hDPSCs isolated from an earlier developmental stage to evaluate the potential usage of these cells for tissue-regenerative therapy. hDPSCs isolated at the crown-completed stage showed a higher proliferation rate than those isolated at a later stage. When the cells from either group were cultured in medium promoting differentiation toward cells of the osteo/odontoblastic lineage, both became alkaline-phosphatase-positive, produced calcified matrix, and were also capable of forming dentin-like matrix on scaffolds in vivo. However, during long-term passage, these cells underwent a change in morphology and lost their differentiation ability. The results of a DNA array experiment showed that the expression of several genes, such as WNT16, was markedly changed with an increasing number of passages, which might have caused the loss of their characteristics as hDPSCs.


Asunto(s)
Células Madre Adultas/citología , Pulpa Dental/citología , Odontoblastos/citología , Odontogénesis/fisiología , Germen Dentario/citología , Adulto , Células Madre Adultas/metabolismo , Técnicas de Cultivo de Célula , Diferenciación Celular/fisiología , Proliferación Celular , Pulpa Dental/crecimiento & desarrollo , Pulpa Dental/metabolismo , Perfilación de la Expresión Génica , Humanos , Tercer Molar/citología , Tercer Molar/crecimiento & desarrollo , Tercer Molar/metabolismo , Odontoblastos/metabolismo , Odontogénesis/genética , Análisis de Secuencia por Matrices de Oligonucleótidos , Medicina Regenerativa , Factores de Tiempo , Ingeniería de Tejidos , Germen Dentario/metabolismo
8.
Kyobu Geka ; 60(1): 45-8, 2007 Jan.
Artículo en Japonés | MEDLINE | ID: mdl-17249538

RESUMEN

Malignant pleural mesothelioma is an aggressive neoplasm with poor prognosis. Extrapleural pneumonectomy is performed as surgical therapy. It is difficult to obtain enough range of view at costophrenic angle. We adopt extrapleural pneumonectomy with wide resection of the chest wall, diaphragm, and pericardium to remove the main lesion at the costophrenic angle and report 6 cases received this surgical procedure. With this procedure, a wide view of costophrenic angle and costal-pericardial angle can be obtained, and the resection margin can be placed outside the chest wall, costophrenic angle and costal-pericardial angle, which enables complete resection of masses at the costophrenic and costal-pericardial angles. Furthermore, extrapleural pneumonectomy with wide resection of the chest wall minimizes the resulting dead space, thereby minimizing the risk of postoperative hemorrhage and empyema. We consider that this procedure can be applied for malignant mesothelioma patients, especially those who have pleural masses at costophrenic angle.


Asunto(s)
Mesotelioma/cirugía , Pericardio/cirugía , Neoplasias Pleurales/cirugía , Neumonectomía/métodos , Pared Torácica/cirugía , Anciano , Humanos , Masculino , Persona de Mediana Edad
9.
J Phys Condens Matter ; 19(26): 266206, 2007 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-21694083

RESUMEN

This work reports a theoretical x-ray absorption near-edge structure (XANES) spectroscopy study at the Ti K-edge in TiO(2) rutile. We present detailed ab initio computations of the Ti K-edge XANES spectrum performed within the multiple-scattering framework. An extensive discussion is presented concerning the size of the cluster needed to reproduce the experimental spectrum, especially regarding the split main absorption line. In addition, the role of the exchange and correlation potential (ECP) in reproducing all the experimental XANES features is discussed. The best agreement between experimental data and computations is obtained by using real ECP potentials, i.e. the energy-dependent Dirac-Hara exchange potential, or by using only the real part of the energy-dependent Hedin-Lundqvist complex potential, together with an additional imaginary constant to account for the core-hole lifetime and the experimental resolution. The addition of the imaginary part of the HL potential worsens the agreement between the experimental and calculated spectra, indicating the failure of the complex part of the Hedin-Lundqvist ECP in accounting for the electron damping in these systems.

10.
Kyobu Geka ; 59(1): 26-30, 2006 Jan.
Artículo en Japonés | MEDLINE | ID: mdl-16440681

RESUMEN

BACKGROUND: The prognosis of lung cancer patients with intrapulmonary metastasis in different lobes (pm2) is poor. However, some patients achieve long-term survival. We retrospectively investigated the prognosis of resected primary lung cancer patients with pm2. METHOD: Among 845 patients with primary lung cancer who underwent complete resection from 1984 to 2003, 14 cases that had lung cancer with pm2 were evaluated about prognostic factors. RESULTS: The overall 5-year survival rate was 9.5%. The analysis of survival curve based on clinicopathological factors (surgical procedure, histology, tumor size, lymph nodal metastasis, pleural invasion, pleural dissemination and number of pm2) revealed that bronchioloalveolar carcinoma (BAC), the absence of pleural invasion and the absence of pleural dissemination are better prognostic factors. CONCLUSION: Lung cancer patients with pm2 whose lesions show BAC histology, the absence of pleural invasion or pleural dissemination may achieve long-term survival and could be candidates for surgical treatment.


Asunto(s)
Neoplasias Pulmonares/patología , Neoplasias Pulmonares/cirugía , Pulmón/patología , Adenocarcinoma Bronquioloalveolar/mortalidad , Adenocarcinoma Bronquioloalveolar/secundario , Adenocarcinoma Bronquioloalveolar/cirugía , Adulto , Anciano , Femenino , Humanos , Neoplasias Pulmonares/mortalidad , Masculino , Persona de Mediana Edad , Pronóstico , Análisis de Supervivencia
11.
Phytomedicine ; 13(1-2): 37-42, 2006 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-16360931

RESUMEN

Isotaxiresinol, the main lignan isolated from the water extract of wood of Taxus yunnanensis, was investigated for its effect on bone loss, on serum biochemical markers for bone remodeling and on uterine tissue, using ovariectomized (OVX) rats as the model of postmenopausal osteoporosis. After oral administration of isotaxiresinol (50 and 100mg/kg/d) for 6 weeks, bone mineral content (BMC) and bone mineral density (BMD) in total and cortical bones were increased as compared to those of OVX control rats, and decreases of three bone strength indexes induced by OVX surgery were prevented. Serum biochemical markers for bone remodeling revealed that isotaxiresinol slightly increased bone formation and significantly inhibited bone resorption without side effect on uterine tissue. These results suggest that isotaxiresinol may be useful for treatment of postmenopausal osteoporosis, especially for prevention of bone fracture induced by estrogen deficiency.


Asunto(s)
Lignanos/farmacología , Lignanos/uso terapéutico , Osteoporosis/tratamiento farmacológico , Taxus/química , Animales , Peso Corporal , Densidad Ósea/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Femenino , Lignanos/efectos adversos , Lignanos/química , Estructura Molecular , Ovariectomía , Ratas , Ratas Wistar
12.
Phytomedicine ; 13(1-2): 67-73, 2006 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-16360935

RESUMEN

Thirty samples of Indonesian medicinal plants were analyzed for their capacity to inhibit in vitro metabolism by human cytochrome P450 3A4 (CYP3A4) and CYP2D6 with a radiometric assay. The MeOH-soluble fractions of 25 samples, prepared from water extracts, demonstrated inhibitory activity more than 50% on the metabolism mediated by CYP3A4, and 21 samples on the metabolism mediated by CYP2D6. Among the MeOH-soluble fractions, Piper nigrum leaf showed the highest inhibitory activity against CYP3A4 (91.7%), and Punica granatum against CYP2D6 (98.1%). The water extracts of which MeOH-soluble fraction showed inhibitory activity more than 70% were fractionated with EtOAc. From the EtOAc-soluble fractions, Curcuma heyneana (67.0%), Pi. cubeba (75.0%), Pi. nigrum fruit (84.0%), Pi. nigrum leaf (85.8%), and Zingiber aromaticum (75.3%) demonstrated inhibitory activity more than 50% on the metabolism mediated by CYP3A4, but only Pi. nigrum fruit (72.8%) and Pi. nigrum leaf (69.1%) showed strong inhibitory activity against CYP2D6. For samples that showed more than 70% inhibition, their IC(50) values were determined. The most potent inhibitory activity against CYP3A4 (IC(50) value of 25 microg/ml) was found for the extract of Pi. nigrum leaf, while that of Catharanthus roseus showed the most potent inhibitory effect against CYP2D6 (IC(50) value of 11 microg/ml). These results should indicate once more the possibility of potential medicinal plant-drug interactions.


Asunto(s)
Inhibidores del Citocromo P-450 CYP2D6 , Inhibidores Enzimáticos del Citocromo P-450 , Inhibidores Enzimáticos/farmacología , Extractos Vegetales/farmacología , Plantas Medicinales/química , Citocromo P-450 CYP2D6/química , Citocromo P-450 CYP2D6/metabolismo , Citocromo P-450 CYP3A , Sistema Enzimático del Citocromo P-450/química , Sistema Enzimático del Citocromo P-450/metabolismo , Inhibidores Enzimáticos/química , Indonesia , Medicina Tradicional , Extractos Vegetales/química
13.
Phytomedicine ; 13(1-2): 109-14, 2006 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-16360940

RESUMEN

Hypoglycemic effects of the H(2)O and MeOH extracts of the wood of Taxus yunnanensis were examined in streptozotocin (STZ)-induced diabetic rats. The H(2)O extract significantly lowered the fasting blood glucose level by 33.7% at a 100mg/kg dose on intraperitoneal administration. From the active H(2)O extract of the wood, three lignans, i.e., isotaxiresinol (1), secoisolariciresinol (2) and taxiresinol (3), were isolated as major components. These lignans were further tested for their hypoglycemic effects on the same experimental model. At a dose of 100mg/kg (i.p.), isotaxiresinol (1) reduced the fasting blood glucose level of diabetic rats by 34.5%, while secoisolariciresinol (2) and taxiresinol (3) reduced by 33.4% and 20.9%, respectively. The blood glucose lowering effects of 1 and 2 were stronger than the mixture of tolbutamide (200mg/kg) and buformin (1mg/kg) used as a positive control, which lowered fasting blood glucose level by 24.0%.


Asunto(s)
Glucemia/metabolismo , Diabetes Mellitus Experimental/tratamiento farmacológico , Extractos Vegetales/química , Extractos Vegetales/farmacología , Taxus/química , Madera , Animales , Butileno Glicoles/química , Butileno Glicoles/farmacología , Diabetes Mellitus Experimental/sangre , Furanos/química , Furanos/farmacología , Hipoglucemia/inducido químicamente , Lignanos/química , Lignanos/farmacología , Masculino , Estructura Molecular , Extractos Vegetales/uso terapéutico , Ratas , Ratas Wistar
14.
Eur J Neurol ; 12(10): 768-73, 2005 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16190914

RESUMEN

Overproduction of interleukin (IL)-6 plays an important role in the pathophysiology of myasthenia gravis (MG), and thymectomy can cause myasthenic crisis because of surgically induced overproduction of IL-6. Preoperative steroid therapy is beneficial in preventing MG crisis during the perioperative period. The purpose of this study was to clarify the effect of preoperative steroid therapy on proinflammatory mediators during the perioperative period of transsternal thymectomy for MG. The study group comprised 20 consecutive MG patients undergoing transsternal thymectomy during the period March 2002 through March 2004. Seventeen of these patients received dose-escalated steroid therapy before thymectomy (steroid treatment group) and three did not (non-steroid treatment group). Serum concentrations of C-reactive protein (CRP) and IL-6 were determined during the perioperative period; clinical outcomes were reviewed, and the results were compared between the two groups. Peak serum IL-6 and CRP concentrations were significantly lower in the steroid treatment group than in the non-steroid treatment group. Amongst perioperative variables subjected to multiple regression analysis, preoperative steroid treatment were found to be the most significant independent predictor of inhibited IL-6 production on postoperative day 1. No postoperative respiratory failure occurred in the steroid treatment group, but it did occur in the non-steroid treatment group. Preoperative steroid therapy can ameliorate IL-6 overproduction and may help stabilize the patient's postoperative condition.


Asunto(s)
Interleucina-6/sangre , Miastenia Gravis/sangre , Esteroides/administración & dosificación , Timectomía/métodos , Anciano , Proteína C-Reactiva/metabolismo , Relación Dosis-Respuesta a Droga , Esquema de Medicación , Femenino , Humanos , Masculino , Persona de Mediana Edad , Miastenia Gravis/tratamiento farmacológico , Miastenia Gravis/metabolismo , Miastenia Gravis/cirugía , Complicaciones Posoperatorias , Estudios Retrospectivos , Factores de Tiempo , Resultado del Tratamiento
15.
Kyobu Geka ; 57(1): 46-50, 2004 Jan.
Artículo en Japonés | MEDLINE | ID: mdl-14733098

RESUMEN

We sought to determine the eligibility of patients with early peripheral lung cancer for intentional limited resection. The clinicopathologic features of 103 patients who underwent lobectomy and mediastinal nodal dissection for early stage peripheral lung cancer measuring 2 cm or less in maximum dimension between 1992 and 2002 were examined retrospectively. The lymph node metastasis and residual cancer after thoracoscopic partial resection were analyzed by the following categories. Three groups were divided by maximum dimension of the primary lesion in the resected specimen; 10 mm or less (n = 11), 15 mm or less (n = 33), and 20 mm or less (n = 59). Two groups were divided by lesion histology; bronchioloalveolar adenocarcinoma (BAC) [n = 42] and invasive lung cancer (n = 61). Residual cancer was found in the residual lobe after thoracoscopic partial resection in 3 of 43 patients who had no diagnosis preoperatively. Their maximum dimensions were 15 mm or less. No lymph node metastasis was detected in the patients with tumor measuring 10 mm or less, and BAC. Intentional limited resection without mediastinal nodal dissection is appropriate for patients with tumor measuring 10 mm or less and BAC. Further investigation associated with partial resection is necessary.


Asunto(s)
Adenocarcinoma Bronquioloalveolar/cirugía , Neoplasias Pulmonares/cirugía , Escisión del Ganglio Linfático , Ganglios Linfáticos/patología , Neumonectomía , Adenocarcinoma Bronquioloalveolar/mortalidad , Adenocarcinoma Bronquioloalveolar/secundario , Anciano , Femenino , Humanos , Neoplasias Pulmonares/mortalidad , Neoplasias Pulmonares/patología , Metástasis Linfática , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Tasa de Supervivencia
16.
Phytother Res ; 15(7): 561-71, 2001 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11746834

RESUMEN

Propolis is a resinous hive product collected by honeybees from various plant sources. It is a popular folk medicine possessing a broad spectrum of biological activities. It has also been used as a health drink in various Asian, European and American countries. Several groups of researchers have focused their attention on the biological activity of propolis and its active principles. Many scientific articles are published every year in different international journals related to the pharmacological properties of propolis. This review article compiles recent findings (since 1995) on the pharmacological properties of propolis focusing on its antihepatotoxic, antitumour, antioxidative, antimicrobial and antiinflammatory properties. The possible mechanism of action of propolis as well as the active compounds are discussed.


Asunto(s)
Fitoterapia , Própolis/uso terapéutico , Antiinfecciosos/uso terapéutico , Antineoplásicos/uso terapéutico , Antioxidantes/uso terapéutico , Humanos , Sustancias Protectoras/uso terapéutico
17.
J Nat Prod ; 64(11): 1465-7, 2001 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11720536

RESUMEN

A new dimeric aporphine alkaloid, phoenicanthusine (1), and six known alkaloids were isolated from the stem bark of Phoenicanthus obliqua. The structure of 1 was elucidated by 1D ((1)H, (13)C) and 2D ((1)H-(1)H COSY, HMQC, HMBC, and NOESY) NMR and HRMS studies. Phoenicanthusine represents the first example of a N-6--C-4' and C-7--C-5' linked dimeric aporphine alkaloid.


Asunto(s)
Annonaceae/química , Aporfinas/aislamiento & purificación , Plantas Medicinales/química , Aporfinas/química , Cromatografía en Capa Delgada , Conformación Molecular , Estructura Molecular , Resonancia Magnética Nuclear Biomolecular , Tallos de la Planta/química , Espectrofotometría Infrarroja , Espectrofotometría Ultravioleta , Sri Lanka
18.
J Am Chem Soc ; 123(47): 11570-6, 2001 Nov 28.
Artículo en Inglés | MEDLINE | ID: mdl-11716710

RESUMEN

Nonlinear polymer topologies composed of cyclic and branched polymer segments are systematically classified by reference to constitutional isomerism in a series of alkanes (CnH2n+2), monocycloalkanes (CnH2n), and polycycloalkanes (CnH2n-2, CnH2n-4, etc). Thus, the total number of chain ends (termini) and of branch points (junctions) are maintained as invariant parameters, as well as the number of branches at each junction and the connectivity of junction. On the other hand, the distance between two adjacent junctions and that between the junction and terminus are taken as variant parameters. On the basis of the classification of polymer topologies, a novel synthetic strategy by an "electrostatic self-assembly and covalent fixation" technique has been proposed to construct a variety of topologically unique polymer architectures.

19.
ASAIO J ; 47(5): 563-4, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11575838

RESUMEN

Primary tissue failure of bioprosthetic heart valves refers primarily to calcification of the leaflets of the bioprosthesis. A 75 year old patient underwent reoperation 15 years after mitral valve replacement with a Carpentier-Edwards porcine bioprosthesis. The extracted bioprosthetic valve was found to have one prolapsed leaflet and a small amount of calcification on all three leaflets without tear or perforation. The two commissures suspending the prolapsed leaflet were detached, causing mitral valve regurgitation.


Asunto(s)
Bioprótesis/efectos adversos , Prótesis Valvulares Cardíacas/efectos adversos , Anciano , Animales , Análisis de Falla de Equipo , Humanos , Masculino , Válvula Mitral , Falla de Prótesis , Reoperación , Porcinos , Factores de Tiempo
20.
J Nat Prod ; 64(9): 1127-32, 2001 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11575942

RESUMEN

The MeOH extract of Nam ginseng (roots and rhizomes of Dracaena angustifolia) afforded nine new compounds, including three spirostanol sapogenins, named namogenins A-C (1-3), four spirostanol saponins, named namonins A-D (4-7), a furostanol saponin, named namonin E (8), and a pregnan glycoside, named namonin F (9), along with another eight known steroidal saponins (10-17). Their structures were determined on the basis of spectral analyses and chemical methods. All compounds were tested for their antiproliferative activity against murine colon 26-L5 carcinoma, human HT-1080 fibrosarcoma, and B-16 BL6 melanoma cells. Compounds 4, 5, and 10 showed potent antiproliferative activity against HT-1080 fibrosarcoma cells, having IC(50) values of 0.2, 0.3, and 0.6 microM, respectively, comparable to that of doxorubicin.


Asunto(s)
Antineoplásicos Fitogénicos/aislamiento & purificación , Liliaceae/química , Sapogeninas/aislamiento & purificación , Saponinas/aislamiento & purificación , Espirostanos/aislamiento & purificación , Animales , Antineoplásicos Fitogénicos/química , Antineoplásicos Fitogénicos/farmacología , Neoplasias del Colon , Doxorrubicina/farmacología , Fibrosarcoma , Humanos , Melanoma , Ratones , Raíces de Plantas/química , Plantas Medicinales/química , Rizoma/química , Sapogeninas/química , Sapogeninas/farmacología , Saponinas/química , Saponinas/farmacología , Espirostanos/química , Espirostanos/farmacología , Células Tumorales Cultivadas/efectos de los fármacos , Vietnam
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