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1.
Osteoporos Int ; 30(3): 697, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30806728

RESUMO

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.
Artigo em Inglês | MEDLINE | ID: mdl-30607458

RESUMO

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.


Assuntos
Força da Mão/fisiologia , Fraturas por Osteoporose/fisiopatologia , Equilíbrio Postural/fisiologia , Fraturas do Rádio/fisiopatologia , Acidentes por Quedas , Adulto , Idoso , Densidade Óssea/fisiologia , Estudos de Casos e Controles , Feminino , Humanos , Pessoa de Meia-Idade , Osteoporose Pós-Menopausa/complicações , Osteoporose Pós-Menopausa/fisiopatologia , Fraturas por Osteoporose/etiologia , Período Pós-Operatório , Curva ROC , Fraturas do Rádio/etiologia , Fraturas do Rádio/cirurgia , Medição de Risco/métodos , Fatores de Risco
3.
Nat Mater ; 13(6): 611-8, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24705382

RESUMO

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.
Artigo em Inglês | MEDLINE | ID: mdl-25215998

RESUMO

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.
Artigo em Inglês | MEDLINE | ID: mdl-24484509

RESUMO

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.


Assuntos
Cabras/fisiologia , Kisspeptinas/farmacologia , Folículo Ovariano/fisiologia , Animais , Corpo Lúteo/efeitos dos fármacos , Corpo Lúteo/fisiologia , Dinoprosta/administração & dosagem , Dinoprosta/farmacologia , Esquema de Medicação , Feminino , Kisspeptinas/administração & dosagem , Ovulação/efeitos dos fármacos , Ovulação/fisiologia
6.
Phys Rev Lett ; 106(20): 202501, 2011 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-21668223

RESUMO

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.

7.
Phys Rev Lett ; 106(5): 052502, 2011 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-21405387

RESUMO

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.

8.
Domest Anim Endocrinol ; 74: 106522, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32841888

RESUMO

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.


Assuntos
Temperatura Corporal/efeitos dos fármacos , Bovinos/fisiologia , Resposta ao Choque Térmico/efeitos dos fármacos , Fragmentos de Peptídeos/farmacologia , Receptores da Neurocinina-3/agonistas , Substância P/análogos & derivados , Animais , Regulação da Temperatura Corporal/efeitos dos fármacos , Regulação da Temperatura Corporal/fisiologia , Feminino , Hormônio Liberador de Gonadotropina/fisiologia , Hormônio Luteinizante/fisiologia , Neurocinina B/fisiologia , Ovário/fisiologia , Fragmentos de Peptídeos/uso terapêutico , Receptores da Neurocinina-3/fisiologia , Transdução de Sinais/fisiologia , Substância P/farmacologia , Substância P/uso terapêutico , Vagina/fisiologia
9.
Anticancer Res ; 41(5): 2661-2667, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33952497

RESUMO

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.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Inibidores de Proteínas Quinases/administração & dosagem , Idoso , Idoso de 80 Anos ou mais , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Intervalo Livre de Doença , Receptores ErbB/genética , Feminino , Humanos , Masculino , Mutação/genética , Inibidores de Proteínas Quinases/efeitos adversos , Resultado do Tratamento
10.
Sci Rep ; 10(1): 22109, 2020 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-33335175

RESUMO

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.
Artigo em Inglês | MEDLINE | ID: mdl-30908995

RESUMO

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.


Assuntos
Compostos de Bifenilo/farmacologia , Estrogênios/administração & dosagem , Cabras/fisiologia , Hormônio Liberador de Gonadotropina/metabolismo , Receptores Opioides kappa/antagonistas & inibidores , Sulfonamidas/farmacologia , Animais , Compostos de Bifenilo/administração & dosagem , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Injeções Intravenosas , Injeções Subcutâneas , Ovariectomia/veterinária , Sulfonamidas/administração & dosagem
12.
Mucosal Immunol ; 12(5): 1201-1211, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31417161

RESUMO

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.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Interferon gama/metabolismo , Interleucina-10/metabolismo , Interleucina-1beta/metabolismo , Transdução de Sinais , Adolescente , Comunicação Celular , Criança , Suscetibilidade a Doenças , Humanos , Doenças Inflamatórias Intestinais/etiologia , Doenças Inflamatórias Intestinais/metabolismo , Doenças Inflamatórias Intestinais/patologia , Doenças Inflamatórias Intestinais/terapia
13.
Oncogene ; 26(28): 4171-8, 2007 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-17311004

RESUMO

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.


Assuntos
Alelos , Predisposição Genética para Doença , Neoplasias Cutâneas/genética , Animais , Linhagem Celular , Hibridização in Situ Fluorescente
14.
Diabet Med ; 25(7): 875-7, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18644076

RESUMO

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.


Assuntos
Diabetes Mellitus Tipo 1/etiologia , Diabetes Mellitus Tipo 2/etiologia , Retinopatia Diabética/etiologia , Interferon gama/fisiologia , Monocinas/metabolismo , Corpo Vítreo/metabolismo , Idoso , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fator A de Crescimento do Endotélio Vascular/metabolismo
15.
New Microbes New Infect ; 18: 18-21, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28491325

RESUMO

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.
Artigo em Inglês | MEDLINE | ID: mdl-17112838

RESUMO

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.


Assuntos
Glomerulosclerose Segmentar e Focal/cirurgia , Transplante de Rim/fisiologia , Biópsia , Família , Feminino , Seguimentos , Glomerulosclerose Segmentar e Focal/patologia , Sobrevivência de Enxerto , Humanos , Doadores Vivos , Masculino , Transplante Homólogo , Resultado do Tratamento
17.
J Natl Cancer Inst ; 71(4): 749-54, 1983 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-6578370

RESUMO

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.


Assuntos
Estradiol/sangue , Albumina Sérica/metabolismo , Globulina de Ligação a Hormônio Sexual/metabolismo , Adulto , Peso Corporal , Inglaterra , Feminino , Humanos , Japão , Pessoa de Meia-Idade , Análise de Regressão
18.
Cancer Res ; 40(1): 162-5, 1980 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-6765916

RESUMO

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.


Assuntos
Mutagênicos , Nitrosaminas/farmacologia , Bacillus subtilis/efeitos dos fármacos , Biotransformação , Escherichia coli/efeitos dos fármacos , Nitrosaminas/síntese química , Nitrosaminas/metabolismo , Salmonella typhimurium/efeitos dos fármacos
19.
Cancer Res ; 56(7): 1512-6, 1996 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-8603395

RESUMO

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.


Assuntos
Antiulcerosos/farmacologia , Antineoplásicos/farmacologia , Neovascularização Patológica/prevenção & controle , Triazinas/farmacologia , Animais , Linhagem Celular , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Neoplasias Experimentais/tratamento farmacológico
20.
Oncogene ; 16(21): 2747-54, 1998 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-9652741

RESUMO

A total of 429 gamma-ray-induced thymic lymphomas were obtained from F1 and backcross mice between BALB/c and MSM strains, about a half of which carried a p53-deficient allele. A genome-wide allelic loss analysis has revealed two loci exhibiting frequent allelic losses but no allelic preference, one is localized within a 2.9 cM region between D12Mit53 and D12Mit279 loci on chromosome 12, and the other is near the D16Mit122/D16Mit162 loci on chromosome 16. The frequency of allelic loss in the D12Mit279 region is 62% and does not differ in tumors between the presence and absence of the p53-deficient allele. In contrast, the loss frequency of D16Mit122 is raised by the existence of p53-deficient allele: 62% for p63(-/+) and 13% for p53(+/+), suggesting co-operative function of the two losses. The D12Mit279 and D16Mit122 regions probably harbor different types of tumor suppressor gene that play key roles in lymphoma development.


Assuntos
Mapeamento Cromossômico , Genes Supressores de Tumor , Perda de Heterozigosidade , Linfoma/genética , Neoplasias do Timo/genética , Animais , Feminino , Raios gama , Genótipo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Proteína Supressora de Tumor p53/genética
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