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1.
Osteoporos Int ; 30(3): 697, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30806728

RESUMEN

The article Lower grip strength and dynamic body balance in women with distal radial fractures, written by. K. Fujita, H. Kaburagi, A. Nimura, T. Miyamoto, Y. Wakabayashi, Y. Seki, H. Aoyama, H. Shimura, R. Kato, A. Okawa was originally published electronically on the publisher's internet portal.

2.
Osteoporos Int ; 30(5): 949-956, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30607458

RESUMEN

In this case-control study, we concluded that women with distal radial fractures who were surgically treated showed lower grip strength and dynamic body balancing than those of controls. These results suggest that measurements of grip strength and dynamic body balance may be useful screening tools to assess future fracture risk. INTRODUCTION: Patients with distal radial fractures (DRFs) are at risk of future fragility fractures. However, their physical characteristics and tendencies for falls remain unclear. We aimed to compare the physical characteristics of women with and without distal radial fractures. METHODS: We included 128 women with a DRF as their first fragility fracture (fracture group) who underwent surgical treatment. Concurrently, 128 age- and sex-matched participants without a history of fragility fractures were selected as controls (control group). The participants underwent assessments of grip strength and the body balancing ability test. Measurements were taken twice in the fracture group, at 2 weeks and 6 months postoperatively, and once in the control group. The body balancing ability test included the Functional Reach Test, Timed Up and Go test (TUG), 2-Step test (2ST), and Timed Uni-pedal Stance test. The participants also completed questionnaires about their health. RESULTS: There were no significant differences (p > 0.05) in patient characteristics between the groups. The fracture group showed lower grip strength across all age groups. In the DRF group, prolonged TUG time was observed at 2 weeks postoperatively in all age groups and at 6 months in participants aged 55-74 years; the 2ST score was significantly lower in participants aged between 65 and 74 years. CONCLUSIONS: Women with DRF demonstrated lower grip strength and dynamic body balancing ability. Lower grip strength and dynamic body balancing ability were identified as significant risk factors in women with DRF, suggesting that these may be useful screening tools to assess fracture risk.


Asunto(s)
Fuerza de la Mano/fisiología , Fracturas Osteoporóticas/fisiopatología , Equilibrio Postural/fisiología , Fracturas del Radio/fisiopatología , Accidentes por Caídas , Adulto , Anciano , Densidad Ósea/fisiología , Estudios de Casos y Controles , Femenino , Humanos , Persona de Mediana Edad , Osteoporosis Posmenopáusica/complicaciones , Osteoporosis Posmenopáusica/fisiopatología , Fracturas Osteoporóticas/etiología , Periodo Posoperatorio , Curva ROC , Fracturas del Radio/etiología , Fracturas del Radio/cirugía , Medición de Riesgo/métodos , Factores de Riesgo
3.
Nat Mater ; 13(6): 611-8, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24705382

RESUMEN

Resonant X-ray diffraction (RXD) uses X-rays in the vicinity of a specific atomic absorption edge and is a powerful technique for studying symmetry breaking by motifs of various multipole moments, such as electric monopoles (charge), magnetic dipoles (spin) and electric quadrupoles (orbital). Using circularly polarized X-rays, this technique has been developed to verify symmetry breaking effects arising from chirality, the asymmetry of an object upon its mirroring. Chirality plays a crucial role in the emergence of functionalities such as optical rotatory power and multiferroicity. Here we apply spatially resolved RXD to reveal the helix chirality of Dy 4f electric quadrupole orientations and its domain structure in DyFe3(BO3)4, which shows a reversible phase transition into an enantiomorphic space-group pair. The present study provides evidence for a helix chiral motif of quadrupole moments developed in crystallographic helix chirality.

4.
Phys Rev Lett ; 113(9): 096403, 2014 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-25215998

RESUMEN

Ultrafast photoinduced transitions of a one-dimensional Mott insulator into two distinct electronic phases, metal and charge-density-wave (CDW) state, were achieved in a bromine-bridged Pd-chain compound [Pd(en)2Br](C5-Y)2H2O (en=ethylenediamine and C5-Y=dialkylsulfosuccinate), by selecting the photon energy of a femtosecond excitation pulse. For the resonant excitation of the Mott-gap transition, excitonic states are generated and converted to one-dimensional CDW domains. For the higher-energy excitation, free electron and hole carriers are produced, giving rise to a transition of the Mott insulator to a metal. Such selectivity in photoconversions by the choice of initial photoexcited states opens a new possibility for the developments of advanced optical switching and memory functions.

5.
Reprod Domest Anim ; 49(2): 338-42, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24484509

RESUMEN

This study evaluated the effects of follicular phase administration of TAK-683, an investigational metastin/kisspeptin analog, on follicular growth, ovulation, luteal function and reproductive hormones in goats. After confirmation of ovulation by transrectal ultrasonography (Day 0), PGF2α (2 mg/head of dinoprost) was administered intramuscularly on Day 10 to induce luteal regression. At 12 h after PGF2α administration, intravenous administration of vehicle or 35 nmol (50 µg)/head of TAK-683 was performed in control (n = 4) and treatment (n = 4) groups, respectively. Blood samples were collected at 6-h intervals for 96 h and then daily until the detection of subsequent ovulation (second ovulation). After the second ovulation, ultrasound examinations and blood sampling were performed every other day or daily until the subsequent ovulation (third ovulation). Mean concentrations of LH and FSH in the treatment group were significantly higher 6 h after TAK-683 treatment than those in the control group (12.0 ± 10.7 vs 1.0 ± 0.7 ng/ml for LH, 47.5 ± 28.2 vs 15.1 ± 3.4 ng/ml for FSH, p < 0.05), whereas mean concentrations of oestradiol in the treatment group decreased immediately after treatment (p < 0.05) as compared with the control group. Ovulation tended to be delayed (n = 2) or occurred early (n = 1) in the treatment group as compared with the control group. For the second ovulation, ovulatory follicles in the treatment group were significantly smaller in maximal diameter than in the control group (3.8 ± 0.5 vs 5.4 ± 0.2 mm, p < 0.05, n = 3). Administration of TAK-683 in the follicular phase stimulates gonadotropin secretion and may have resulted in ovulation of premature follicles in goats.


Asunto(s)
Cabras/fisiología , Kisspeptinas/farmacología , Folículo Ovárico/fisiología , Animales , Cuerpo Lúteo/efectos de los fármacos , Cuerpo Lúteo/fisiología , Dinoprost/administración & dosificación , Dinoprost/farmacología , Esquema de Medicación , Femenino , Kisspeptinas/administración & dosificación , Ovulación/efectos de los fármacos , Ovulación/fisiología
6.
Phys Rev Lett ; 106(5): 052502, 2011 Feb 04.
Artículo en Inglés | MEDLINE | ID: mdl-21405387

RESUMEN

The ß-decay half-lives of 38 neutron-rich isotopes from (36)Kr to (43)Tc have been measured; the half-lives of (100)Kr, (103-105)Sr, (106-108)Y, (108-110)Zr, (111,112)Nb, (112-115)Mo, and (116,117)Tc are reported here. The results when compared with previous standard models indicate an overestimation in the predicted half-lives by a factor of 2 or more in the A≈110 region. A revised model based on the second generation gross theory of ß decay better predicts the measured half-lives and suggests a more rapid flow of the rapid neutron-capture process (r-matter flow) through this region than previously predicted.

7.
Phys Rev Lett ; 106(20): 202501, 2011 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-21668223

RESUMEN

The low-lying states in ¹°6Zr and ¹°8Zr have been investigated by means of ß-γ and isomer spectroscopy at the radioactive isotope beam factory (RIBF), respectively. A new isomer with a half-life of 620 ± 150 ns has been identified in ¹°8Zr. For the sequence of even-even Zr isotopes, the excitation energies of the first 2⁺ states reach a minimum at N = 64 and gradually increase as the neutron number increases up to N = 68, suggesting a deformed subshell closure at N = 64. The deformed ground state of ¹°8Zr indicates that a spherical subshell gap predicted at N = 70 is not large enough to change the ground state of ¹°8Zr to the spherical shape. The possibility of a tetrahedral shape isomer in ¹°8Zr is also discussed.

8.
Domest Anim Endocrinol ; 74: 106522, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-32841888

RESUMEN

Heat stress disrupts reproductive function in cattle. In summer, high ambient temperature and humidity elevate core body temperature, which is considered to be detrimental to reproductive abilities in cattle. Neurokinin B (NKB) is a factor that generates pulsatile GnRH and subsequent LH secretion in mammals. Recent studies have reported that NKB-neurokinin 3 receptor (NK3R) signaling is associated with heat-defense responses in rodents. The present study aimed to clarify the role of NKB-NK3R signaling in thermoregulation in cattle. We examined the effects of an NK3R-selective agonist, senktide, on vaginal temperature as an indicator of core body temperature in winter and summer. In both seasons, continuous infusion of senktide for 4 h immediately decreased vaginal temperature, and the mean temperature change in the senktide-treated group was significantly lower than that of both vehicle- and GnRH-treated groups. Administration of GnRH induced LH elevation, but there was no significant difference in vaginal temperature change between GnRH- and vehicle-treated groups. Moreover, we investigated the effects of senktide on ovarian temperature. Senktide treatment seemed to suppress the increase in ovarian temperature from 2 h after the beginning of administration, although the difference between groups was not statistically significant. Taken together, these results suggest that senktide infusion caused a decline in the vaginal temperature of cattle, in both winter and summer seasons, and this effect was not due to the gonadotropin-releasing action of senktide. These findings provide new therapeutic options for senktide to support both heat-defense responses and GnRH/LH pulse generation.


Asunto(s)
Temperatura Corporal/efectos de los fármacos , Bovinos/fisiología , Respuesta al Choque Térmico/efectos de los fármacos , Fragmentos de Péptidos/farmacología , Receptores de Neuroquinina-3/agonistas , Sustancia P/análogos & derivados , Animales , Regulación de la Temperatura Corporal/efectos de los fármacos , Regulación de la Temperatura Corporal/fisiología , Femenino , Hormona Liberadora de Gonadotropina/fisiología , Hormona Luteinizante/fisiología , Neuroquinina B/fisiología , Ovario/fisiología , Fragmentos de Péptidos/uso terapéutico , Receptores de Neuroquinina-3/fisiología , Transducción de Señal/fisiología , Sustancia P/farmacología , Sustancia P/uso terapéutico , Vagina/fisiología
9.
Anticancer Res ; 41(5): 2661-2667, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33952497

RESUMEN

BACKGROUND/AIM: The significance of epidermal growth factor receptor (EGFR) mutation in untreated patients with non-small cell lung cancer (NSCLC) remains uncertain. We aimed to determine the significance of EGFR mutation in patients who received best supportive care (BSC) alone, and compare the outcomes of only EGFR- tyrosine kinase inhibitors (TKI)-treated vs. BSC patients. PATIENTS AND METHODS: Between April 1991-August 2018, 1,197 patients diagnosed with unresectable NSCLC at our institutions were enrolled in the study. RESULTS: Among 226 patients who underwent EGFR mutation analysis and received BSC alone, 35 and 191 did and did not harbor the mutation, and the median survival times (MST) did not differ significantly between these groups. A comparison of only EGFR-TKI-treated and BSC patients with EGFR mutation revealed that the former had a three times longer MST than the latter. CONCLUSION: Our results may help explain the benefit of EGFR-TKI for patients who would be directed towards BSC.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Inhibidores de Proteínas Quinasas/administración & dosificación , Anciano , Anciano de 80 o más Años , Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Pulmón de Células no Pequeñas/patología , Supervivencia sin Enfermedad , Receptores ErbB/genética , Femenino , Humanos , Masculino , Mutación/genética , Inhibidores de Proteínas Quinasas/efectos adversos , Resultado del Tratamiento
10.
Sci Rep ; 10(1): 22109, 2020 Dec 17.
Artículo en Inglés | MEDLINE | ID: mdl-33335175

RESUMEN

Ti2O3 exhibits unique metal-insulator transition (MIT) at ~ 450 K over a wide temperature range of ~ 150 K. The close relationship between MIT and crystal deformation has been proposed. However, as physical properties are governed by the thermodynamic equilibrium in bulk systems, conducting experimental studies under different lattice deformations remains challenging. Epitaxial thin films can offer high flexibility to accommodate adaptive crystal lattices and provide efficient platforms for investigating the MIT. In this study, we report the synthesis of corundum-type Ti2O3 films on various growth temperatures. We found that the metallic ground states appeared in the films grown at low temperatures. The electronic ground states were further investigated by the electronic-structure calculations. Results suggest that the electrical properties of Ti2O3 films were governed by the c/a ratio of the crystal structure, and the absence of the MIT was attributed to the lattice deformation characterized by an elongated c lattice constant.

11.
Domest Anim Endocrinol ; 68: 83-91, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-30908995

RESUMEN

Pulsatile gonadotropin-releasing hormone (GnRH) secretion is indispensable for reproduction in mammals. Kisspeptin neurons in the hypothalamic arcuate nucleus (ARC), referred to as KNDy neurons because of the coexpression of neurokinin B and dynorphin A, are considered as components of the GnRH pulse generator that produces rhythmic GnRH secretion. The present study aimed to investigate if peripheral administration of PF-4455242, a κ-opioid receptor (KOR, a dynorphin A receptor) antagonist, facilitates pulsatile luteinizing hormone (LH) secretion and GnRH pulse generator activity in estrogen-treated ovariectomized Shiba goats to determine the possibility of using KOR antagonists to artificially control ovarian activities. PF-4455242 was intravenously infused for 4 h (1 or 10 µmol/kg body weight/4 h) or as a single subcutaneous injection (1 or 10 µmol/kg body weight). In a separate experiment, the same KOR antagonist (10 µmol/kg body weight/4 h) was intravenously infused during the recording of multiple unit activity (MUA) in the ARC that reflects the activity of the GnRH pulse generator to test the effects of KOR antagonist administration on GnRH pulse generator activity. Intravenous infusion and single subcutaneous injection of the KOR antagonist significantly increased the frequency of LH pulses compared with controls. Intravenous infusion of KOR antagonist also significantly increased the frequency of episodic bursts in the MUA. The present study demonstrates that peripherally administered KOR antagonist stimulates pulsatile LH secretion by acting on the GnRH pulse generator, and peripheral administration of PF-4455242 can be used to facilitate pulsatile LH secretion, which in turn facilitates ovarian activities in farm animals.


Asunto(s)
Compuestos de Bifenilo/farmacología , Estrógenos/administración & dosificación , Cabras/fisiología , Hormona Liberadora de Gonadotropina/metabolismo , Receptores Opioides kappa/antagonistas & inhibidores , Sulfonamidas/farmacología , Animales , Compuestos de Bifenilo/administración & dosificación , Femenino , Regulación de la Expresión Génica/efectos de los fármacos , Inyecciones Intravenosas , Inyecciones Subcutáneas , Ovariectomía/veterinaria , Sulfonamidas/administración & dosificación
12.
Mucosal Immunol ; 12(5): 1201-1211, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31417161

RESUMEN

Uncontrolled interferon γ (IFNγ)-mediated T-cell responses to commensal microbiota are a driver of inflammatory bowel disease (IBD). Interleukin-10 (IL-10) is crucial for controlling these T-cell responses, but the precise mechanism of inhibition remains unclear. A better understanding of how IL-10 exerts its suppressive function may allow identification of individuals with suboptimal IL-10 function among the heterogeneous population of IBD patients. Using cells from patients with an IL10RA deficiency or STAT3 mutations, we demonstrate that IL-10 signaling in monocyte-derived dendritic cells (moDCs), but not T cells, is essential for controlling IFNγ-secreting CD4+ T cells. Deficiency in IL-10 signaling dramatically increased IL-1ß release by moDCs. IL-1ß boosted IFNγ secretion by CD4+ T cells either directly or indirectly by stimulating moDCs to secrete IL-12. As predicted a signature of IL-10 dysfunction was observed in a subgroup of pediatric IBD patients having higher IL-1ß expression in activated immune cells and macroscopically affected intestinal tissue. In agreement, reduced IL10RA expression was detected in peripheral blood mononuclear cells and a subgroup of pediatric IBD patients exhibited diminished IL-10 responsiveness. Our data unveil an important mechanism by which IL-10 controls IFNγ-secreting CD4+ T cells in humans and identifies IL-1ß as a potential classifier for a subgroup of IBD patients.


Asunto(s)
Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD4-Positivos/metabolismo , Células Dendríticas/inmunología , Células Dendríticas/metabolismo , Interferón gamma/metabolismo , Interleucina-10/metabolismo , Interleucina-1beta/metabolismo , Transducción de Señal , Adolescente , Comunicación Celular , Niño , Susceptibilidad a Enfermedades , Humanos , Enfermedades Inflamatorias del Intestino/etiología , Enfermedades Inflamatorias del Intestino/metabolismo , Enfermedades Inflamatorias del Intestino/patología , Enfermedades Inflamatorias del Intestino/terapia
13.
Oncogene ; 26(28): 4171-8, 2007 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-17311004

RESUMEN

Although several familial cancer genes with high-penetrance mutations have been identified, the major genetic component of susceptibility to sporadic cancers is attributable to low-penetrance alleles. These 'weak' tumor susceptibility genes do not segregate as single Mendelian traits and are therefore difficult to find in studies of human populations. Previously, we have proposed that a combination of germline mapping and analysis of allele-specific imbalance in tumors may be used to refine the locations of susceptibility genes using mouse models of cancer. Here, we have used linkage analysis and congenic mouse strains to map the major skin tumor susceptibility locus Skts1 within a genetic interval of 0.9 cM on proximal chromosome 7. This interval lies in an apparent recombination cold spot, and corresponds to a physical distance of about 15 Mb. We therefore, used patterns of allele-specific imbalances in tumors from backcross and congenic mice to refine the location of Skts1. We demonstrate that this single tumor modifier locus has a dramatic effect on the allelic preference for imbalance on chromosome 7, with at least 90% of tumors from the congenics showing preferential gain of markers on the chromosome carrying the susceptibility variant. Importantly, these alterations enabled us to refine the location of Skts1 at higher resolution than that attained using the congenic mice. We conclude that low-penetrance susceptibility genes can have strong effects on patterns of allele-specific somatic genetic changes in tumors, and that analysis of the directionality of these somatic events provides an important and rapid route to identification of germline genetic variants that confer increased cancer risk.


Asunto(s)
Alelos , Predisposición Genética a la Enfermedad , Neoplasias Cutáneas/genética , Animales , Línea Celular , Hibridación Fluorescente in Situ
14.
Diabet Med ; 25(7): 875-7, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18644076

RESUMEN

AIM: To determine the intravitreous concentration of monokine induced by interferon-gamma (Mig) in patients with diabetic retinopathy (DR) and the relation between Mig and vascular endothelial growth factor (VEGF). RESEARCH DESIGN AND METHODS: Vitreous samples were obtained at the time of vitrectomy from 41 eyes of 38 DR patients (30 with active DR and 11 with inactive DR) and from 15 eyes of 15 non-diabetic patients who had macular disease (control subjects). Human Mig and VEGF were quantified using a FACS Caliber flow cytometer. RESULTS: The vitreous concentration of Mig was increased significantly in patients with both active and inactive DR [148.0 (31.6-997.2; median range) and 82.3 (25.7-347.7) pg/ml, respectively] compared with control subjects [21.0 (5.2-74.3) pg/ml; P < 0.0001 and P < 0.001, respectively]. In DR patients, a significant (P < 0.01) correlation was observed between vitreous concentrations of Mig and VEGF. CONCLUSION: Our results suggest that Mig may play an important role in the pathogenesis of DR and works in consort with VEGF in the progression of pathological angiogenesis in DR.


Asunto(s)
Diabetes Mellitus Tipo 1/etiología , Diabetes Mellitus Tipo 2/etiología , Retinopatía Diabética/etiología , Interferón gamma/fisiología , Monocinas/metabolismo , Cuerpo Vítreo/metabolismo , Anciano , Estudios de Casos y Controles , Femenino , Humanos , Masculino , Persona de Mediana Edad , Factor A de Crecimiento Endotelial Vascular/metabolismo
15.
New Microbes New Infect ; 18: 18-21, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28491325

RESUMEN

Propionimicrobium lymphophilum is an anaerobic Gram-positive bacillus that exists in human skin and urinary tract. The pathogenicity is, however, not well known. Only two cases of urinary tract infection have been described recently. In the case presented here, the bacterium was isolated, concomitant with Actinotignum schaalii, from blood culture of a patient with fever and difficulty of urination. The bacteria were identified by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry and 16S rRNA sequencing. The case was successfully treated with ampicillin/sulbactam.

16.
Transplant Proc ; 38(9): 2819-22, 2006 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-17112838

RESUMEN

INTRODUCTION: Focal segmental glomerulosclerosis (FSGS) has a tendency to recur frequently after kidney transplantation. We evaluated 12 cases to examine the incidence and long-term outcomes of recurrent FSGS. MATERIALS AND METHODS: Twelve patients with renal failure caused by FSGS received kidney allografts from living related donors. Tacrolimus or cyclosporine was used in combination with prednisolone and azathioprine or mycophenolate mofetil. RESULTS: The mean graft survival was 87.4 +/- 46.8 months. The graft survival rates in FSGS recipients were at 1 year, 100%; 5 years, 79.6%; 10 years, 68.2%. Two out of four recipients experienced graft loss due to chronic rejection. The other two out of four recipients with graft loss displayed severe proteinuria diagnosed as recurrence of FSGS. To treat recurrent FSGS, plasma exchange was partially effective to reduce proteinuria. CONCLUSION: Our incidence of recurrent FSGS is 16.7% with graft survivals at 5 and 10 years of 79.6% and 68.2%, respectively. The recurrence of FSGS happened after scheduled reductions in immunosuppressants. Careful observation is required with maintenance of immunosuppression in these patients.


Asunto(s)
Glomeruloesclerosis Focal y Segmentaria/cirugía , Trasplante de Riñón/fisiología , Biopsia , Familia , Femenino , Estudios de Seguimiento , Glomeruloesclerosis Focal y Segmentaria/patología , Supervivencia de Injerto , Humanos , Donadores Vivos , Masculino , Trasplante Homólogo , Resultado del Tratamiento
17.
J Natl Cancer Inst ; 71(4): 749-54, 1983 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-6578370

RESUMEN

Normal Japanese women had significantly more of their blood 17 beta-estradiol (E2) bound to sex hormone-binding globulin (SHBG) (53%) than British women (30%) and conversely less bound to albumin. While the proportion of SHBG-bound E2 increased with SHBG capacity and while binding fell as weight increased, the differences between the races do not appear to be explicable in terms of SHBG capacity or weight. At a given SHBG capacity, the Japanese women had more E2 bound to the protein than the British women. Where weights in the 2 populations overlapped, the Japanese women still had more of their E2 bound to SHBG than did the British women. Our results suggested that the affinity of albumin for E2 is lower in Japanese women.


Asunto(s)
Estradiol/sangre , Albúmina Sérica/metabolismo , Globulina de Unión a Hormona Sexual/metabolismo , Adulto , Peso Corporal , Inglaterra , Femenino , Humanos , Japón , Persona de Mediana Edad , Análisis de Regresión
18.
Cancer Res ; 40(1): 162-5, 1980 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-6765916

RESUMEN

4-(N-Butylnitrosamino)-4-hydroxybutyric acid lactone (BBAL) was synthesized as a possible intermediate produced by metabolic activation of a selective bladder carcinogen, N-butyl-N-(3-carboxypropyl)nitrosamine. BBAL was stable in neutral sodium phosphate buffer (ionic strength, 0.2), having a half-life of more than 30 hr at 25 degrees. The mutagenic effects of BBAL were tested with the use of Salmonella typhimurium TA1535 and Escherichia coli B/rWP2-try-, WP2-try-hcr-, and Sd4. The gene-damaging effects were assayed by repair tests with Bacillus subtilis H17 (rec+) and M45 (rec-). BBAL showed potent effects in the mutation and repair tests on all the strains tested without activation. A possibility is suggested for the metabolic activation of N-butyl-N-(3-carboxypropyl)nitrosamine to BBAL by alpha-hydroxylation at the site of the 3-carboxypropyl chain followed by lactonization in target tissues prior to interaction with macromolecules to lead to carcinogenesis.


Asunto(s)
Mutágenos , Nitrosaminas/farmacología , Bacillus subtilis/efectos de los fármacos , Biotransformación , Escherichia coli/efectos de los fármacos , Nitrosaminas/síntesis química , Nitrosaminas/metabolismo , Salmonella typhimurium/efectos de los fármacos
19.
Cancer Res ; 56(7): 1512-6, 1996 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-8603395

RESUMEN

Irsogladine used clinically as an anti-gastric ulcer agent, at 10(-6)-10(-4)M, inhibited cell proliferation and tubular morphogenesis of vascular endothelial cells, but the proliferation of human epidermoid cancer or glioma cells was not inhibited by this drug, even at 10(-4)M. In vivo studies demonstrated that p.o. administration of irsogladine significantly inhibited tumor growth of human glioma cells in mice, and histological analysis showed a dramatic decrease of the neovascularization in the tumors. In mice transplanted with chambers containing human glioma cells or hepatic cancer cells, irsogladine also inhibited angiogenesis. These in vivo and in vitro assays demonstrate that irsogladine may be a unique and potent inhibitor of tumor angiogenesis.


Asunto(s)
Antiulcerosos/farmacología , Antineoplásicos/farmacología , Neovascularización Patológica/prevención & control , Triazinas/farmacología , Animales , Línea Celular , Humanos , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Neoplasias Experimentales/tratamiento farmacológico
20.
Oncogene ; 20(37): 5243-7, 2001 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-11526516

RESUMEN

BALB/c is a susceptible strain for the development of gamma-ray induced mouse thymic lymphoma whereas MSM shows resistance. Association analysis of 220 backcross mice between the two strains using 67 markers was carried out to identify loci involved in the control of susceptibility. The genotype of mice with lymphoma showed excess heterozygosity relative to MSM homozygosity at D2Mit15 and D4Mit12 and was skewed toward MSM-derived alleles at D5Mit5. The P values in Mantel-Cox test were 0.0048 (D2Mit15), 0.0034 (D4Mit12) and 0.0048 (D5Mit5), suggesting association at the three loci in the susceptibility. Cooperative effect on lymphomagenesis was also observed among the three loci. To obtain independent evidence for linkage at D4Mit12, we made partially congenic mice in which a D4Mit12 region in BALB/c was replaced by MSM-derived homolog. Examination for the lymphoma susceptibility in 78 progeny of the congenic mice confirmed the effect of the locus near D4Mit12 (P=0.0037). The result, together with the linkage analysis, shows that the locus near D4Mit12 is regarded as a confirmed linkage but the other two loci as marginally suggestive.


Asunto(s)
Rayos gamma , Predisposición Genética a la Enfermedad , Linfoma/etiología , Linfoma/genética , Neoplasias Experimentales/genética , Neoplasias Inducidas por Radiación/genética , Neoplasias del Timo/etiología , Neoplasias del Timo/genética , Alelos , Animales , Cruzamientos Genéticos , Femenino , Marcadores Genéticos , Genotipo , Heterocigoto , Homocigoto , Pérdida de Heterocigocidad , Masculino , Ratones , Ratones Congénicos , Ratones Endogámicos BALB C
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