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1.
Science ; 294(5549): 2136-8, 2001 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-11739950

RESUMEN

Superconductors can be used as dissipation-free electrical conductors as long as vortices are pinned. Vortices in high-temperature superconductors, however, behave anomalously, reflecting the anisotropic layered structure, and can move readily, thus preventing their practical use. Specifically, in a magnetic field tilted toward the layer plane, a special vortex arrangement (chain-lattice state) is formed. Real-time observation of vortices using high-resolution Lorentz microscopy revealed that the images of chain vortices begin to disappear at a much lower temperature, Td, than the superconducting transition temperature, Tc. We attribute this image disappearance to the longitudinal oscillation of vortices along the chains.

2.
Chem Commun (Camb) ; (8): 912-4, 2006 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-16479309

RESUMEN

The synthesis of a mg amount of pure argon containing fullerene allowed the synthesis of the first endohedral superconductors with critical temperatures lower than expected, an indication of the strong influence of the argon atom on the C60 cage.

3.
Clin Nephrol ; 65(4): 290-3, 2006 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-16629230

RESUMEN

We report the case of a patient with uremic pleuropericarditis who showed a marked improvement following corticosteroid therapy. A 66-year-old man who had been on hemodialysis therapy for 13 years was admitted to our hospital presenting with increases in bilateral pleural effusions and pericardial effusion. Repeated thoracentesis showed hemorrhagic and exudative findings. Pleural and pericardial fluid cytologic examination, bacterial culture and acid-fast staining showed negative findings. Despite the administration of antibiotics and antituberculosis drugs, low-grade fever continued and C-reactive protein level remained high. A pleural biopsy revealed fibrinous pleuritis without infectious disease or malignancy. He was diagnosed as having uremic pleuropericarditis on the basis of the clinicopathological features, but had been unresponsive to conventional treatments including repeated thoracentesis and the continuance of hemodiafiltration using nafamostat mesylate. Ultimately, both pleural and pericardial effusions were controlled after the treatment with prednisolone at an initial dose of 50 mg per day. In conclusion, corticosteroid therapy seems to be useful for treating patients with conventional therapy-resistant uremic pleuropericarditis.


Asunto(s)
Antiinflamatorios/uso terapéutico , Fallo Renal Crónico/complicaciones , Pericarditis/tratamiento farmacológico , Pleuresia/tratamiento farmacológico , Prednisolona/uso terapéutico , Anciano , Humanos , Masculino , Pericarditis/etiología , Pericarditis/patología , Pleuresia/etiología , Pleuresia/patología
4.
Clin Nephrol ; 65(1): 48-52, 2006 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-16429842

RESUMEN

Herein we describe a case of a patient with rapidly progressive glomerulonephritis after Chlamydia pneumoniae infection. An 88-year-old woman who had had C. pneumoniae infection two months previously was admitted to our hospital with complaints of dyspnea and generalized edema. Laboratory tests revealed acute renal failure, polyclonal hypergammaglobulinemia, highly increased level of C-reactive protein, and hematoproteinuria. A renal biopsy revealed mesangial and endocapillary proliferative glomerulonephritis with crescents. She responded to high-dose steroids, cyclophosphamide, minocycline, and plasma exchange treatment with the remission of oliguric renal failure. The percentage of the subset of CD3+ TCR+ Vbeta11+ cells markedly increased to 9.6% (normal range: < 1.04%) at the onset of the disease and decreased to 0.1% after the treatment. These clinicopathological features were similar to those of superantigen-associated glomerulonephritis after methicillin-resistant Staphylococcus aureus infection. We suggest that the superantigenic mechanism is one of the possible pathomechanisms of this glomerulonephritis.


Asunto(s)
Infecciones por Chlamydia/complicaciones , Chlamydophila pneumoniae/inmunología , Glomerulonefritis/etiología , Glomerulonefritis/inmunología , Superantígenos/inmunología , Anciano , Progresión de la Enfermedad , Femenino , Glomerulonefritis/patología , Humanos , Inmunohistoquímica
5.
Clin Nephrol ; 64(6): 401-11, 2005 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-16370152

RESUMEN

BACKGROUND: alpha-Smooth muscle actin (SMA), CD44, hyaluronic acid (HA) and osteopontin (OPN) are involved in crescent formation; however, the correlation between these molecules during the formation and progression of the crescents in human glomerulonephritis (GN) has not been fully evaluated. METHODS: To investigate the expression of alpha-SMA, CD44, HA, OPN and CD68 renal biopsy specimens from 14 patients with crescentic GN were examined by immunohistochemistry. All crescents were separated into cellular, fibrocellular and fibrous. The extent of staining in each crescent was scored semiquantitatively. The change in the expression of each molecule and its correlation with other molecules during the formation and progression of the crescents were estimated statistically. RESULTS: The expression of alpha-SMA was significantly up-regulated in the fibrocellular crescents compared with that in the cellular and fibrous crescents. The expression of CD44, OPN and CD68 was significant in the cellular crescents compared with that in the fibrocellular and fibrous crescents. The deposition of HA in the three groups of crescents was high level. However, that of HA was not significant among three groups of crescent. The expression of CD44 in the cellular crescents correlated significantly with the expression of OPN and CD68, and the deposition of HA in the cellular crescents. The expression of OPN in the cellular crescents correlated with the deposition of HA and the expression of CD68 in the cellular crescents. The expression of alpha-SMA in the cellular and fibrocellular crescents correlated with the deposition of HA in the cellular and fibrocellular crescents. CONCLUSION: The expression of CD44, HA, OPN and CD68 was up-regulated at the early stage of the crescent formation in human crescentic GN. Moreover, myofibroblasts and cell-matrix interactions mediated by the CD44-OPN and CD44-HA receptor-ligand pairs may play important roles in the formation and progression of the crescents.


Asunto(s)
Actinas/metabolismo , Glomerulonefritis/metabolismo , Receptores de Hialuranos/metabolismo , Ácido Hialurónico/metabolismo , Sialoglicoproteínas/metabolismo , Adolescente , Adulto , Anciano , Biopsia , Femenino , Glomerulonefritis/patología , Humanos , Inmunohistoquímica , Masculino , Persona de Mediana Edad , Osteopontina , Estadísticas no Paramétricas , Regulación hacia Arriba
6.
Clin Nephrol ; 64(4): 295-9, 2005 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16240901

RESUMEN

Herein we describe a case of a patient with elderly-onset systemic lupus erythematosus presenting as acute renal failure due to disseminated intravascular coagulation. A 78-year-old man was admitted to our hospital with fever and generalized lymphadenopathy. He was diagnosed as having systemic lupus erythematosus on the basis of renal involvement, hematological abnormality and positivity for antinuclear and anti-double-stranded DNA antibodies. Renal biopsy revealed lupus nephritis (class III and V (A/C)) with focal glomerular thrombosis. He responded to hemodialysis and corticosteroid therapy with remission of serological values and renal function. Possible mechanisms underlying the coexistence of these conditions are discussed.


Asunto(s)
Lesión Renal Aguda/etiología , Coagulación Intravascular Diseminada/complicaciones , Lupus Eritematoso Sistémico/complicaciones , Lesión Renal Aguda/patología , Anciano , Biopsia , Humanos , Glomérulos Renales/ultraestructura , Lupus Eritematoso Sistémico/patología , Masculino , Microscopía Electrónica
7.
J Int Med Res ; 33(6): 707-10, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-16372590

RESUMEN

We present a rare case of colon perforation caused by hydrostatic irrigation enema in a patient with chronic renal failure. A 76-year-old woman was admitted to our hospital because of an exacerbation of lumbar pain and increased difficulty in walking. She had a medical history of traumatic neck pain and chronic lower back pain, which had been treated with non-steroidal anti-inflammatory drugs (NSAIDs) for 8 years. On admission, the C-reactive protein level was 6.8 mg/dl, so we planned to do a colonoscopy to determine the cause of inflammation. The patient developed abdominal pain approximately 3.5 h after a pre-procedural enema was administered. An emergency operation was performed and a small perforation was found in the sigmoid colon. We conclude that the cause of the colon perforation was a combination of the use of a hydrostatic retrograde irrigation enema in a patient with chronic renal failure who had been treated with long-term NSAIDs.


Asunto(s)
Colon Sigmoide/lesiones , Colonoscopía/métodos , Enema/efectos adversos , Fallo Renal Crónico , Peritonitis/cirugía , Anciano , Antiinflamatorios no Esteroideos/uso terapéutico , Femenino , Humanos , Inflamación/diagnóstico , Inflamación/tratamiento farmacológico , Peritonitis/diagnóstico , Peritonitis/etiología , Tomógrafos Computarizados por Rayos X
8.
Int J Hematol ; 72(3): 353-7, 2000 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11185994

RESUMEN

In hemophagocytic lymphohistiocytosis (HLH), cytokine-induced pancytopenia is a common finding and is associated with hypoplastic and hypocellular bone marrow and abundant hemophagocytosis. To date, neutrophil nuclear segmentation abnormalities have not been clarified in HLH patients. We report a study of bone marrow from 6 cases of HLH that showed abnormal granulocytes, dyserythropoietic changes, and micromegakaryocytes mimicking the findings in myelodysplasia at the onset of disease. Pelger-Huët anomalies were particularly noted in all cases. The increased levels of cytokines in these cases may have caused cellular damage leading to the morphological changes in the bone marrow of these HLH patients. The impact of these findings on pathophysiology and prognosis in HLH patients remains to be determined.


Asunto(s)
Médula Ósea/patología , Histiocitosis de Células no Langerhans/patología , Síndromes Mielodisplásicos/patología , Adolescente , Niño , Preescolar , Diagnóstico Diferencial , Femenino , Humanos , Lactante , Masculino
9.
J Neurol Sci ; 156(1): 99-101, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-9559995

RESUMEN

Sera from patients with Guillain-Barré syndrome (GBS) frequently have antibodies to various gangliosides. We report a girl with GBS after Mycoplasma pneumoniae infection who had serum IgG antibody to GM1b ganglioside as well as the cold agglutinins. The cold agglutinins are polyclonal IgM autoantibodies to 'I' antigen on erythrocytes. Ganglioside GM1b contains the terminal moiety shared with sialylated I antigen, a main receptor for M. pneumoniae. In this patient, the anti-GM1b antibody may be elicited in a similar mechanism producing anti-I antibody, and functioned in the development of GBS.


Asunto(s)
Autoanticuerpos/análisis , Gangliósido G(M1)/análogos & derivados , Inmunoglobulina G/análisis , Neumonía por Mycoplasma/complicaciones , Neumonía por Mycoplasma/inmunología , Polirradiculoneuropatía/etiología , Polirradiculoneuropatía/inmunología , Aglutininas/inmunología , Niño , Crioglobulinas , Femenino , Gangliósido G(M1)/inmunología , Humanos
10.
J Org Chem ; 65(11): 3269-73, 2000 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-10843605

RESUMEN

The isolation of a new fullerene dimer, C(122)H(4), and its structural characterization by (13)C NMR and (1)H NMR spectroscopy and by UV/vis and IR spectroscopy are reported. The structure of this dimer consists of two fullerene cages, which are directly connected through two C-C bonds and two methylene bridges. Consequently, adjacent hexagonal faces of the two fullerene cages are arranged in a face to face manner. Molecular orbital calculations indicate that the proximity of the fullerene cages results in significant through space overlap in both the HOMO and LUMO. As a consequence of this overlap, the electrochemistry of the dimer shows electronic communication with stepwise reduction of each cage.

11.
Neurosurgery ; 42(2): 405-7, 1998 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-9482196

RESUMEN

OBJECTIVE AND IMPORTANCE: Ruptured arteriovenous malformations (AVMs) are important causes of spontaneous intracerebral hemorrhages. This is a report of emergency hematoma removal, avoiding damage to the nidus of the AVM, using intraoperative color Doppler imaging. CLINICAL PRESENTATION: A 38-year-old woman suddenly presented with coma. The patient underwent emergency surgery immediately after admission, without preoperative angiographic examination, because of progressive neurological deterioration caused by a massive hematoma in the right basal ganglia, as diagnosed with computed tomographic scanning. INTERVENTION: A right frontotemporoparietal craniotomy was performed. Intraoperative ultrasound imaging with a color Doppler system (EUP-NS32, 5 MHz; Hitachi Medical, Tokyo, Japan) clearly demonstrated a nidus complex in the hematoma. Based on the imaging, effective decompression of the hematoma was performed without damage to the AVM complex. CONCLUSION: Color Doppler imaging (with real-time availability) of an atypical hematoma provided significant information on the vascular lesion causing the hematoma and could reduce the surgical risks during emergency evacuation of large intracerebral hemorrhages resulting from ruptured AVMs.


Asunto(s)
Hemorragia Cerebral/etiología , Hemorragia Cerebral/terapia , Servicios Médicos de Urgencia , Hematoma/etiología , Hematoma/terapia , Malformaciones Arteriovenosas Intracraneales/complicaciones , Ultrasonografía Doppler en Color , Adulto , Angiografía Cerebral , Hemorragia Cerebral/diagnóstico , Femenino , Hematoma/diagnóstico , Humanos , Malformaciones Arteriovenosas Intracraneales/diagnóstico , Tomografía Computarizada por Rayos X
12.
Neurol Res ; 23(7): 724-30, 2001 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11680512

RESUMEN

Subarachnoid hemorrhage (SAH) elicits an inflammatory response in the subarachnoid space, which is mediated by the release of various cytokines. To assess their involvement in post-hemorrhagic complications, we determined the source and time-course of the release of inflammatory cytokines and acute-phase proteins in cerebrospinal fluid (CSF) following SAH. Concentrations of interleukin (IL)- 1beta, IL-6, transforming growth factor-beta1 (TGF-beta1) and C-reactive protein (CRP) in CSF of 36 patients with SAH were measured by enzyme-linked immunoabsorbent assay (ELISA). Floating cells collected from the CSF were centrifuged four to six days after SAH, and examined immunohistochemically. Intracellular IL-1beta and IL-6 were examined by flow cytometric analysis. The molecular weight of TGF-beta1 in CSF of 30 patients was examined by Western blot analysis. The TGF-beta1 levels of patients who had undergone ventriculoperitoneal (VP) shunt (n = 19) was significantly higher than nonshunt group (n = 16). The CRP levels of VP shunt group was significantly higher than nonshunt group. IL-6 concentration was maximal within day 0-1 and it was secreted by neutrophils and monocytes. ELISA showed consistently low levels of IL-1beta, whereas a proportion of monocytes and lymphcytes were IL- 1beta-positive by flow cytometric analysis. TGF-beta1 levels were also maximal on day 0-1 according to ELISA, although it tended to be in the inactive form derived from platelets. A 25 kDa band of TGF-1 was detectable for at least 13 days after SAH, which may have been secreted in part by neutrophils and monocytes. CRP levels in CSF peaked on day 2-3. The present results suggest that leukocytes induced by SAH play an important role in post-hemorrhagic inflammation in the subarachnoid space by releasing IL-6 and TGF-beta1. The CRP and TGF-beta1 levels in CSF are strongly concerned with communicating hydrocephalus after SAH.


Asunto(s)
Líquido Cefalorraquídeo/metabolismo , Quimiotaxis de Leucocito/inmunología , Citocinas/líquido cefalorraquídeo , Encefalitis/líquido cefalorraquídeo , Encefalitis/etiología , Leucocitos/metabolismo , Hemorragia Subaracnoidea/complicaciones , Hemorragia Subaracnoidea/fisiopatología , Adulto , Anciano , Anciano de 80 o más Años , Western Blotting , Proteína C-Reactiva/líquido cefalorraquídeo , Proteína C-Reactiva/inmunología , Líquido Cefalorraquídeo/inmunología , Citocinas/inmunología , Encefalitis/inmunología , Ensayo de Inmunoadsorción Enzimática , Femenino , Citometría de Flujo , Humanos , Inmunohistoquímica , Interleucina-1/líquido cefalorraquídeo , Interleucina-1/inmunología , Interleucina-6/líquido cefalorraquídeo , Interleucina-6/inmunología , Leucocitos/inmunología , Masculino , Persona de Mediana Edad , Monocitos/inmunología , Monocitos/metabolismo , Neutrófilos/inmunología , Neutrófilos/metabolismo , Factor de Crecimiento Transformador beta/líquido cefalorraquídeo , Factor de Crecimiento Transformador beta/inmunología
13.
Chem Biol Interact ; 116(3): 181-98, 1998 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-9920461

RESUMEN

We studied atrazine (ATZ) metabolism in male and female rat liver microsomes in vitro, and the major metabolite was deisopropylatrazine (DeiPr-ATZ) with deethylatrazine (DeEt-ATZ) and 1-hydroxyisopropylatrazine (iPrOH-ATZ) as minor metabolites in both sexes. The enzyme kinetics of ATZ biotransformation were examined by means of Eadie-Hofstee analyses. Although no remarkable sex difference of Michaelis Menten values for each pathway was observed, Cl(int)S (Vmax/Km) for DeiPr-ATZ, DeEt-ATZ and iPrOH-ATZ were slightly higher in female than in male rats. The formation of DeiPr-ATZ, DeEt-ATZ and iPrOH-ATZ from ATZ was substantially inhibited by SKF-525A, metyrapone, diallyl sulfide, 7-ethoxycoumarin, benzphetamine, nicotine, testosterone and lauric acid in both sexes. Cimetidine effectively inhibited the formation of all metabolites in male rats. On the other hand, the inhibition rates of the formation of DeiPr-ATZ and iPrOH-ATZ by cimetidine in female rats were lower than those in male rats, and DeEt-ATZ was hardly affected by the chemicals. In contrast with the results for cimetidine, the inhibition of ATZ biotransformation by bufuralol was more effective in female than in male rats. Anti-rat CYP2B1 and CYP2E1 antibodies effectively inhibited DeiPr-ATZ, DeEt-ATZ and iPrOH-ATZ formations in both sexes. Anti-rat CYP2C11 antibody also inhibited the three metabolites in both sexes, with the inhibition rates higher in male than in female rats, similar to cimetidine. In the case of anti-rat CYP2D1 antibody, the inhibitory effect on ATZ biotransformation in male rats was less than that in female rats. On the other hand, anti-rat CYP1A2, CYP3A2 and CYP4A1 antibodies did not affect the ATZ biotransformation in either sex. There was no significant correlation between the formation rate of ATZ metabolites and P450 isoform levels in either sex. These results may mean that CYP2B2, CYP2C11, CYP2D1 (only iPrOH-ATZ formation) and CYP2E1 in male rats, and CYP2B2, CYP2D1 and CYP2E1 in female rats are involved ATZ metabolism in liver, and that the substrate specificity of P450 isoforms for ATZ is broad.


Asunto(s)
Atrazina/farmacocinética , Sistema Enzimático del Citocromo P-450/metabolismo , Herbicidas/farmacocinética , Isoenzimas/metabolismo , Microsomas Hepáticos/enzimología , Animales , Anticuerpos/farmacología , Atrazina/metabolismo , Biotransformación , Cromatografía Líquida de Alta Presión , Inhibidores Enzimáticos del Citocromo P-450 , Sistema Enzimático del Citocromo P-450/inmunología , Interacciones Farmacológicas , Femenino , Herbicidas/metabolismo , Immunoblotting , Isoenzimas/antagonistas & inhibidores , Isoenzimas/inmunología , Cinética , Masculino , Microsomas Hepáticos/metabolismo , Ratas , Ratas Sprague-Dawley , Factores Sexuales
14.
Clin Nephrol ; 51(4): 255-6, 1999 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10230560

RESUMEN

Sulpyrine is commonly used in Japan. We report a case of acute renal failure due to acute tubulointerstitial nephritis (ATIN), which we believe was associated with the use of sulpyrine.


Asunto(s)
Antiinflamatorios no Esteroideos/efectos adversos , Dipirona/efectos adversos , Nefritis Intersticial/inducido químicamente , Enfermedad Aguda , Lesión Renal Aguda/inducido químicamente , Lesión Renal Aguda/patología , Resultado Fatal , Femenino , Humanos , Riñón/patología , Persona de Mediana Edad , Nefritis Intersticial/patología
15.
Clin Nephrol ; 49(5): 321-4, 1998 May.
Artículo en Inglés | MEDLINE | ID: mdl-9617498

RESUMEN

A 57-year-old man with monoclonal gamma-globulinemia was admitted because of edema and proteinuria. A renal biopsy specimen showed lobular glomerulonephritis associated with deposition of material that was positive for IgG, C3, C1q, fibrin, kappa light chain, and lambda light chain but was not stained by Congo red. Glomeruli showed massive electron-dense deposits with two kinds of unusual, highly organized crystalline structures in the mesangial matrix and peripheral capillary loops. Clinically, the patient had nephrotic syndrome, microscopic hematuria, and hypertension. No Bence-Jones protein or cryoglobulin was found in the urine or serum. Immunoelectrophoresis of blood and urine revealed increased IgG-lambda paraprotein, but no free light chains were found. This case was not associated with amyloidosis, systemic lupus erythematosus, light chain deposition disease, cryoglobulinemia, or multiple myeloma. Immunotactoid glomerulopathy was diagnosed. Treatment with oral prednisone was effective for the management of nephrotic syndrome and renal dysfunction. Glomerular deposition of two kinds of microtubular structure in immunotactoid glomerulopathy has rarely been reported.


Asunto(s)
Glomerulonefritis/patología , Inmunoglobulina G/análisis , Cadenas lambda de Inmunoglobulina/análisis , Glomérulos Renales/ultraestructura , Microtúbulos/ultraestructura , Paraproteinemias/complicaciones , Humanos , Masculino , Persona de Mediana Edad
16.
Clin Nephrol ; 58(2): 161-5, 2002 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-12227690

RESUMEN

A 47-year-old Japanese woman with both Takayasu's arteritis (TA) and systemic lupus erythematosus (SLE) presented with unequal pulses in the upper extremities, diarrhea and proteinuria. In 1986, when she was 38 years old, angiography revealed stenosis of the left subclavian artery. In 1994, SLE was diagnosed on the basis of clinical and laboratory findings, including renal dysfunction, hematologic and immunologic abnormalities, a high titer of antinuclear antibody and a positive lupus band test on the skin. Renal biopsy showed lupus nephritis and glomerular lesions with a bubble-like appearance of the glomerular capillary wall with TA. Lupus nephritis coexisting with glomerulonephropathy associated with TA has rarely been reported.


Asunto(s)
Membrana Basal/patología , Glomérulos Renales/patología , Nefritis Lúpica/complicaciones , Arteritis de Takayasu/complicaciones , Biopsia , Diagnóstico Diferencial , Femenino , Glomerulonefritis Membranosa/complicaciones , Glomerulonefritis Membranosa/diagnóstico , Humanos , Lupus Eritematoso Sistémico/complicaciones , Lupus Eritematoso Sistémico/diagnóstico , Nefritis Lúpica/diagnóstico , Persona de Mediana Edad , Arteritis de Takayasu/diagnóstico
17.
Food Chem Toxicol ; 22(6): 409-14, 1984 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-6539729

RESUMEN

The metabolism in rats of sucrose esters of stearic acid and palmitic acid was studied in vivo and in vitro using esters labelled with 14C at the sucrose of fatty-acid moiety. In excretion studies, the ratio of expired radioactivity to absorbed radioactivity after oral administration of the sucrose esters labelled at the sucrose moiety was similar to that after the administration of [14C]sucrose. A similar correlation between the ester labelled at the fatty-acid moiety and the free [14C]fatty acid was also observed. No intact sucrose ester was detected in the urine. Studies in vitro using everted intestinal sacs showed that there was virtually no transport of 14C-labelled sucrose esters from the mucosal to the serosal solution through the intestinal tissues, and that the enzymes in the intestinal mucosa played a more important role in the hydrolysis of sucrose esters than did those in the digestive fluid. In studies of intestinal absorption through the mesenteric lymphatic system, during the 24 hr after ingestion 1.8% of the administered radioactivity was recovered in the lymph after dosing with [U-14C]sucrose monostearate whereas 20% was recovered in the lymph after dosing with sucrose [1-14C]monostearate. This difference in levels of recovery of administered radioactivity indicated that sucrose monostearate was absorbed only after hydrolysis. No intact ester was detected in the lymph or in the portal or femoral blood. The results of all of these experiments show that the sucrose esters are hydrolysed to sucrose and fatty acids prior to intestinal absorption.


Asunto(s)
Sacarosa/análogos & derivados , Absorción , Administración Oral , Animales , Heces/análisis , Hidrólisis , Técnicas In Vitro , Absorción Intestinal , Sistema Linfático/metabolismo , Masculino , Sistema Porta/metabolismo , Ratas , Ratas Endogámicas , Sacarosa/sangre , Sacarosa/metabolismo , Sacarosa/orina
18.
Food Chem Toxicol ; 41(3): 359-74, 2003 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-12504168

RESUMEN

Stevia mixture, sweeteners extracted from the leaves of Stevia rebaudiana Bertoni, consists mainly of stevioside and rebaudioside A (glycosides of the diterpene derivative steviol). The aim of this study was to investigate human intestinal metabolism of stevia mixture and its alpha-glucose derivative (known in Japan as enzymatically modified stevia) by LC/MS/ESI analysis. Degradation was examined by incubating stevia mixture, enzymatically modified stevia, stevioside, rebaudioside A, alpha-monoglucosylstevioside, alpha-monoglucosylrebaudioside A and the aglycone, steviol with pooled human faecal homogenates (obtained from five healthy volunteers) for 0, 8 and 24 h under anaerobic conditions. Stevia mixture, enzymatically modified stevia, stevioside and rebaudioside A (0.2 mg/ml) were completely eliminated within 24 h, whereas no degradation of steviol (0.08 and 0.2 mg/ml) appeared to be found during the incubation period. Stevia mixture, stevioside and rebaudioside A appeared to be hydrolyzed to steviol by human intestinal microflora: this observation is consistent with previous rat metabolism studies. Similarly, enzymatically modified stevia appeared to be metabolized via stevia components and, finally, to steviol. This study suggests that there are apparently no species differences in intestinal metabolism of stevia mixture between rats and humans.


Asunto(s)
Sistema Digestivo/microbiología , Diterpenos de Tipo Kaurano , Heces/química , Glucósidos/metabolismo , Extractos Vegetales/metabolismo , Stevia/química , Edulcorantes/metabolismo , Adulto , Anaerobiosis , Animales , Bacterias Anaerobias/metabolismo , Cromatografía por Intercambio Iónico , Cromatografía Liquida , Diterpenos/química , Heces/microbiología , Cromatografía de Gases y Espectrometría de Masas , Glucósidos/química , Humanos , Hidrólisis , Cinética , Masculino , Peso Molecular , Extractos Vegetales/química , Extractos Vegetales/farmacocinética , Ratas , Especificidad de la Especie , Stevia/metabolismo , Relación Estructura-Actividad , Edulcorantes/química , Edulcorantes/farmacocinética , Terpenos/química
19.
J Clin Neurosci ; 8(1): 23-6, 2001 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11322121

RESUMEN

Owing to the deep location of the posterior cerebral artery (PCA) and its close relationship with the brainstem and surrounding vital structures, surgical treatment of aneurysms in this region is complex. This study was undertaken in an attempt to better delineate the surgical risks of PCA aneurysms. A retrospective analysis was undertaken in 11 patients with PCA aneurysm surgically treated between 1988 and 1996 at Shinshu University and its affiliated hospitals. Data regarding surgical strategy, surgical complications and outcomes were analysed. Seven aneurysms were saccular (including one mycotic) and the other four were fusiform, dissecting, thrombosed and an infundibular dilatation. The locations of the aneurysms were at the P1 segment in two patients, P1-P2 junction in two, P2 segment in six and P3 segment in one. Six saccular non-mycotic aneurysms were treated with neck clipping and the other five aneurysms were treated each with proximal occlusion of the parent artery, excision of the aneurysm or wrapping. All aneurysms were satisfactorily exposed except one large saccular aneurysm. Surgical outcomes were either good recovery or moderate disability in 10 patients, and severe disability in one patient with a large aneurysm due to temporal lobe contusion. In conclusion it is the responsibility of the surgeon dealing with rare PCA aneurysms to be aware of these specific characteristics and to appreciate which surgical technique is appropriate for each patient.


Asunto(s)
Aneurisma Intracraneal/patología , Aneurisma Intracraneal/cirugía , Arteria Cerebral Posterior/patología , Arteria Cerebral Posterior/cirugía , Adulto , Anciano , Encéfalo/irrigación sanguínea , Encéfalo/patología , Encéfalo/fisiopatología , Angiografía Cerebral , Circulación Cerebrovascular , Humanos , Aneurisma Intracraneal/diagnóstico por imagen , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Arteria Cerebral Posterior/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Resultado del Tratamiento
20.
J Vet Med Sci ; 54(5): 837-43, 1992 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-1420562

RESUMEN

A Japanese black calf with cyanosis, tachycardia, tachypnea and systolic murmur died of hypoxemia and cardiac insufficiency on the 38th day after birth. We could not establish the diagnosis during it's life. However, anatomically corrected malposition (ACM) with ventricular septal defect was confirmed at autopsy. There was situs solitus of the viscera and atria with atrio-ventricular discordance and ventriculo-arterial concordance. The ventricles demonstrated l-loop, i.e. on the right-sided ventricle there was a markedly enlarged morphologic left ventricle, and on the left-sided ventricle there was a hypoplastic morphologic right ventricle with a stenotic tricuspid valve and Ebstein-like deformity. The right posterior aorta originated from the left ventricle. The pulmonary artery arose from the left-sided right ventricle via infundibulum. There was a fibrous continuity between the aortic and mitral valve. We considered that this is the first reported case of bovine ACM.


Asunto(s)
Bovinos/anomalías , Cardiopatías Congénitas/veterinaria , Animales , Ecocardiografía/veterinaria , Corazón/fisiopatología , Cardiopatías Congénitas/patología , Cardiopatías Congénitas/fisiopatología , Pruebas de Función Cardíaca/veterinaria , Masculino , Miocardio/patología
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