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1.
Andrologia ; 50(1)2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28224697

RESUMEN

Diabetes mellitus (DM) affects the male ejaculatory function. This study was designed to evaluate the role of oxidative stress in the development of diabetes-induced dysfunction of vas deferens (VD) in the rat. DM was induced by streptozotocin in 40 male Wistar rats. Subsequently, the diabetic animals were divided into three groups: DM group, DM + Eda group and DM + Tau group. These groups were administered saline, edaravone and taurine, respectively, daily for 4 weeks. Another group of ten rats served as a control group. DM was diagnosed in the 40 streptozotocin-injected rats. DM significantly reduced the VD weight. Additionally, DM induced in vitro VD hypercontractility, VD histological abnormalities and increased the serum and VD tissue concentration of malondialdehyde. VD immunohistochemistry revealed overexpression of three markers of oxidative stress. DM significantly reduced serum testosterone levels. No live birth was documented in all DM rats in mating experiments. Antioxidants significantly improved all the aforementioned parameters, except the testosterone levels. This study indicates a deleterious impact of DM-induced oxidative stress on VD histological and functional features. Antioxidant treatment may provide an adjunct tool to alleviate ejaculatory disorders for male patients with type 1 diabetes.


Asunto(s)
Antioxidantes/farmacología , Diabetes Mellitus Experimental/fisiopatología , Estrés Oxidativo/efectos de los fármacos , Conducto Deferente/efectos de los fármacos , Animales , Antipirina/análogos & derivados , Antipirina/farmacología , Diabetes Mellitus Experimental/metabolismo , Edaravona , Masculino , Malondialdehído/metabolismo , Ratas , Ratas Wistar , Taurina/farmacología , Conducto Deferente/fisiopatología
2.
Dis Esophagus ; 30(12): 1-5, 2017 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-28881881

RESUMEN

Basaloid squamous cell carcinoma (BSC) of the esophagus is classified as an epithelial malignant tumor and is a rare variant of squamous cell carcinoma (SCC). Most previous reports have suggested that advanced BSC has a poorer prognosis than typical SCC because of its high biological malignancy, but the biological activity of superficial BSC remains unclear. Twenty cases of superficial BSC, which underwent surgical resection in Tokai University Hospital between January 2004 and December 2013, were analyzed retrospectively. Among these cases, 19 cases with a T1 depth of invasion (BSC group) were compared with 180 cases of SCC that were resected during the same period and were pathologically diagnosed as T1 (SCC group). The frequency of lymph node metastasis in the T1 BSC group was significantly lower (2 patients, 11%) than that in the SCC group (84 patients, 47%) (P = 0.005). The frequency of lymphatic invasion in the BSC group was also lower (9 patients, 47%) than that in the SCC group (131 patients, 73%) (P = 0.021). The pathological type of the metastatic lymph node was BSC in all the superficial BSC cases with lymph node metastasis. This study demonstrated that lymph node metastasis was less likely to occur in cases with superficial BSC than in cases with superficial SCC.


Asunto(s)
Carcinoma de Células Escamosas/patología , Neoplasias Esofágicas/patología , Ganglios Linfáticos/patología , Anciano , Anciano de 80 o más Años , Carcinoma de Células Escamosas/secundario , Carcinoma de Células Escamosas/cirugía , Neoplasias Esofágicas/cirugía , Femenino , Humanos , Metástasis Linfática , Vasos Linfáticos/patología , Masculino , Persona de Mediana Edad , Invasividad Neoplásica , Estudios Retrospectivos , Tasa de Supervivencia
3.
Microbiology (Reading) ; 162(2): 420-432, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26678992

RESUMEN

Lactobacillus plantarum strains produce either glycerol (Gro)- or ribitol (Rbo)-backbone wall teichoic acid (WTA) (Gro-WTA and Rbo-WTA, respectively). The strain WCFS1 has been shown to be able to activate the tarIJKL locus involved in Rbo-WTA synthesis when the tagD1F1F2 locus for Gro-WTA synthesis was mutated, resulting in switching of the native Gro-WTA into Rbo-WTA. Here, we identify a regulator involved in the WTA backbone alditol switching and activation of the tarIJKL locus. Promoter reporter assays of the tarI promoter (Ptar) demonstrated its activity in the Rbo-WTA-producing mutant derivative (ΔtagF1-2) but not in the parental strain WCFS1. An electrophoresis mobility shift assay using a Ptar nucleotide fragment showed that this fragment bound to Ptar-binding protein(s) in a cell-free extract of WCFS1. Three proteins were subsequently isolated using Ptar bound to magnetic beads. These proteins were isolated efficiently from the lysate of WCFS1 but not from the lysate of its ΔtagF1-2 derivative, and were identified as redox-sensitive transcription regulator (Lp_0725), catabolite control protein A (Lp_2256) and TetR family transcriptional regulator (Lp_1153). The role of these proteins in Ptar regulation was investigated by knockout mutagenesis, showing that the Δlp_1153 mutant expressed the tarI gene at a significantly higher level, supporting its role as a repressor of the tarIJKL locus. Notably, the Δlp_1153 mutation also led to reduced expression of the tagF1 gene. These results show that Lp_1153 is a regulatory factor that plays a role in WTA alditol switching in Lb. plantarum WCFS1 and we propose to rename this gene/protein wasR/WasR, for WTA alditol switch regulator.


Asunto(s)
Regulación Bacteriana de la Expresión Génica , Lactobacillus plantarum/genética , Nucleotidiltransferasas/genética , Fosfotransferasas/genética , Deshidrogenasas del Alcohol de Azúcar/genética , Ácidos Teicoicos/biosíntesis , Pared Celular/química , Lactobacillus plantarum/metabolismo , Nucleotidiltransferasas/biosíntesis , Fosfotransferasas/biosíntesis , Deshidrogenasas del Alcohol de Azúcar/biosíntesis
4.
Rev Laryngol Otol Rhinol (Bord) ; 135(4-5): 171-4, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-26521363

RESUMEN

INTRODUCTION: The 35delG mutation in the connexin 26 gene is the most common mutation that generates deafness, but its frequency in different countries is strongly based on its ethnicity. Brazilians belong to different ethnic groups. OBJECTIVES: To report the frequency of homo and heterozygosis 35delG mutation in a population with severe to profound bilateral sensorineural deafness, and separate them by ethnicity. METHODS: 100 individuals were studied with severe to profound hearing loss, with no other etiology found, and tested for 35delG mutation. The group presented the following ethnicity distribution: 25% Blacks; 30% Latin Europeans; 26.2% Blacks/Latin Europeans and 2.3% native. RESULTS: The 35delG mutation was found in 20% of patients: 15% were heterozygous and 5% homozygous. All homozygous were of Latin European origin. CONCLUSION: Ethnicity shows marked determination of the presence of the 35delG mutation, and it was only found in homozygosis in the group of Latin Europeans.


Asunto(s)
Población Negra/estadística & datos numéricos , Conexinas/genética , Eliminación de Gen , Pérdida Auditiva Sensorineural/etnología , Pérdida Auditiva Sensorineural/genética , Hispánicos o Latinos/estadística & datos numéricos , Población Blanca/estadística & datos numéricos , Adolescente , Biomarcadores/metabolismo , Brasil/etnología , Conexina 26 , Consanguinidad , Estudios Transversales , Femenino , Pérdida Auditiva Sensorineural/diagnóstico , Heterocigoto , Homocigoto , Humanos , Masculino , Grupos de Población/estadística & datos numéricos , Valor Predictivo de las Pruebas , Medición de Riesgo , Factores de Riesgo , Sensibilidad y Especificidad , Índice de Severidad de la Enfermedad
5.
Br J Cancer ; 109(6): 1537-42, 2013 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-24002591

RESUMEN

BACKGROUND: Oestrogens usually stimulate the progression of oestrogen receptor (ER)-positive breast cancer. Paradoxically, high-dose oestrogens suppress the growth of these tumours in certain circumstances. METHODS: We prospectively examined the efficacy and safety of ethinylestradiol treatment (3 mg per day oral) in postmenopausal patients with advanced or recurrent ER-positive breast cancer who had previously received endocrine therapies, especially those with resistance to aromatase inhibitors. RESULTS: Eighteen patients were enrolled with the median age of 63 years and the mean observation time of 9.2 months. Three cases withdrew within 1 week due to oestrogen flare reactions with nausea, fatigue and muscle-skeletal pain. The response rate was 50% (9 out of 18), and the clinical benefit rate was 56% (10 out of 18). The stable disease (<6 months) was 17% (3 out of 18) and another 2 cases were judged as progressive disease. Time-to-treatment failure including 2 on treatment was a median of 5.6 months (range 0.1 to 14.5(+)). Although vaginal bleeding or endometrial thickening was observed in patients receiving long-term treatment, there were no severe adverse events, such as deep venous thrombosis or other malignancies. CONCLUSION: Although the mechanism of this treatment has not been fully understood, our data may contribute to change the common view of late-stage endocrine therapy.


Asunto(s)
Antineoplásicos Hormonales/uso terapéutico , Inhibidores de la Aromatasa/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Estrógenos/uso terapéutico , Etinilestradiol/uso terapéutico , Anciano , Anciano de 80 o más Años , Antineoplásicos Hormonales/administración & dosificación , Antineoplásicos Hormonales/efectos adversos , Inhibidores de la Aromatasa/administración & dosificación , Neoplasias de la Mama/patología , Estrógenos/efectos adversos , Etinilestradiol/efectos adversos , Femenino , Humanos , Estimación de Kaplan-Meier , Persona de Mediana Edad , Metástasis de la Neoplasia , Proyectos Piloto , Posmenopausia , Estudios Prospectivos
6.
Anaesthesia ; 68(5): 478-83, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23521655

RESUMEN

We performed a randomised, crossover study to investigate the effects of intravenous sedation on grip strength and bite force. Twenty male volunteers received a bolus intravenous injection of midazolam (0.02 mg.kg(-1)) together with a 30-min propofol infusion designed to achieve an effect-site concentration of 1.0 µg.ml(-1). Observed variables included bispectral index, observer's assessment of alertness/sedation, correct answer rate of Stroop colour-word test, grip strength and bite force. Grip strength decreased from a median (IQR [range]) of 483 (443-517 [380-586]) N to 358 (280-405 [108-580]) N (p < 0.001) during sedation and recovered following flumazenil administration, while bite force increased from 818 (593-1026 [405-1406]) N to 1377 (1243-1585 [836-2357]) N (p < 0.001) during sedation. Although bite force gradually returned to baseline following flumazenil administration, it remained increased throughout the experimental period. We conclude that bite force increased during intravenous sedation and that this may have clinical implications.


Asunto(s)
Fuerza de la Mordida , Fuerza de la Mano/fisiología , Hipnóticos y Sedantes/farmacología , Midazolam/farmacología , Fuerza Muscular/efectos de los fármacos , Músculo Esquelético/efectos de los fármacos , Propofol/farmacología , Adulto , Sedación Consciente , Monitores de Conciencia , Estudios Cruzados , Flumazenil/farmacología , Humanos , Hipnóticos y Sedantes/administración & dosificación , Inyecciones Intravenosas , Masculino , Midazolam/administración & dosificación , Dinamómetro de Fuerza Muscular , Pruebas Neuropsicológicas , Propofol/administración & dosificación , Tamaño de la Muestra , Test de Stroop
7.
Kyobu Geka ; 65(5): 397-400, 2012 May.
Artículo en Japonés | MEDLINE | ID: mdl-22569499

RESUMEN

Neoplasm and cardiac diseases are rarely found at the same time. If the standard treatment for both of these diseases is operation, several problems arise;1 stage or 2 stage operation, which operation should be done 1st etc. Especially, if cardiac operation needs cardiopulmonary bypass, neoplasm may grow faster. In such cases, we must decide operative procedure carefully.


Asunto(s)
Procedimientos Quirúrgicos Cardíacos , Neoplasias/complicaciones , Anciano , Femenino , Neoplasias Cardíacas/cirugía , Defectos del Tabique Interatrial/cirugía , Máquina Corazón-Pulmón , Humanos , Neoplasias Pulmonares/complicaciones , Neoplasias Pulmonares/cirugía , Masculino , Persona de Mediana Edad , Neoplasias del Recto/complicaciones , Neoplasias del Recto/cirugía
8.
Phys Rev E ; 106(2-2): 025205, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-36109929

RESUMEN

A developing supercritical collisionless shock propagating in a homogeneously magnetized plasma of ambient gas origin having higher uniformity than the previous experiments is formed by using high-power laser experiment. The ambient plasma is not contaminated by the plasma produced in the early time after the laser shot. While the observed developing shock does not have stationary downstream structure, it possesses some characteristics of a magnetized supercritical shock, which are supported by a one-dimensional full particle-in-cell simulation taking the effect of finite time of laser-target interaction into account.

9.
Phys Rev E ; 105(2-2): 025203, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35291161

RESUMEN

We present an experimental method to generate quasiperpendicular supercritical magnetized collisionless shocks. In our experiment, ambient nitrogen (N) plasma is at rest and well magnetized, and it has uniform mass density. The plasma is pushed by laser-driven ablation aluminum (Al) plasma. Streaked optical pyrometry and spatially resolved laser collective Thomson scattering clarify structures of plasma density and temperatures, which are compared with one-dimensional particle-in-cell simulations. It is indicated that just after the laser irradiation, the Al plasma is magnetized by a self-generated Biermann battery field, and the plasma slaps the incident N plasma. The compressed external field in the N plasma reflects N ions, leading to counterstreaming magnetized N flows. Namely, we identify the edge of the reflected N ions. Such interacting plasmas form a magnetized collisionless shock.

10.
Kyobu Geka ; 64(5): 383-6, 2011 May.
Artículo en Japonés | MEDLINE | ID: mdl-21591439

RESUMEN

With the overall increase in ischemic heart disease (IHD), cases combining arteriosclerosis obliterans (ASO) of the lower extremities and IHD are on the rise. Therefore, it is necessary to consider methods and timing of operation. These cases have occasionally large collateral pathways from the internal thoracic artery (ITA) to the femoral artery via the epigastric artery. To prevent irreversible ischemia of the lower limbs after harvesting of ITA, we planned to perform a one-stage operation for ASO-combined IHD. Revascularization of the lower extremities was performed 1st. Subsequently coronary artery bypass grafting with ITA was completed. The operative courses were uneventful.


Asunto(s)
Arteriosclerosis Obliterante/cirugía , Puente de Arteria Coronaria/métodos , Pierna/irrigación sanguínea , Isquemia Miocárdica/cirugía , Procedimientos Quirúrgicos Vasculares/métodos , Anciano , Arteriosclerosis Obliterante/complicaciones , Humanos , Masculino , Isquemia Miocárdica/complicaciones
11.
J Exp Med ; 162(1): 393-8, 1985 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-2989412

RESUMEN

A human T cell leukemia/lymphoma virus (HTLV)-I-infected B cell clone expressed Tac antigen on its cell surface and responded to recombinant interleukin 2 (IL-2) by increased production of IgM without any increase in proliferation. Anti-Tac antibody completely inhibited the IL-2-induced differentiation of this HTLV-I-infected B cell clone. This study demonstrates that HTLV-I can directly infect normal mature human B cells, and that the Tac antigen, which may be induced by infection with HTLV-I, is the functional receptor for IL-2-induced B cell differentiation. The availability of such cell lines and clones should provide useful tools to delineate precisely the differentiation step in the human B cell cycle.


Asunto(s)
Linfocitos B/inmunología , Transformación Celular Viral , Deltaretrovirus/inmunología , Interleucina-2/inmunología , Antígenos de Superficie/inmunología , Diferenciación Celular , Células Clonales/inmunología , Humanos , Inmunoglobulina M/biosíntesis , Activación de Linfocitos , Linfocinas/farmacología , Receptores Inmunológicos/inmunología , Receptores de Interleucina-2 , Infecciones por Retroviridae/inmunología , Miembro 7 de la Superfamilia de Receptores de Factores de Necrosis Tumoral
12.
J Pathol ; 217(1): 42-53, 2009 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-18973187

RESUMEN

Necl-5 is an immunoglobulin-like molecule that was originally identified as a poliovirus receptor. Although Necl-5 expression is often up-regulated in cancer cells, its pathophysiological significance in the development of cancer remains unclear. We investigated the roles of Necl-5 in the development of colitis-associated neoplasia. Necl-5-deficient mice were generated and treated with dimethylhydrazine (DMH) and/or dextran sodium sulphate (DSS) to induce colitis and its associated neoplasias. Colon tissues were examined for histology, Ki-67 expression by immunohistochemistry and K-ras gene mutation. Colon tumours occurred significantly less frequently in heterozygous (Necl-5(+/-)) or homozygous Necl-5-deficient (Necl-5(-/-)) mice than in wild-type (WT) mice with DMH/DSS treatment. Total ulcer index and inflammatory cell infiltration were significantly lower in Necl-5(-/-) mice than in WT mice with DSS alone or DMH/DSS treatment. Colon tumours in both WT and Necl-5(-/-) mice showed high cell proliferation ability but lacked K-ras mutation. The total Ki-67 labelling index in non-neoplastic colon epithelium was significantly higher in WT (45.9 +/- 0.94) than in Necl-5(+/-) (34.3 +/- 1.40) or Necl-5(-/-) (27.7 +/- 1.15) mice with DMH/DSS treatment (p < 0.001). Necl-5 plays a role in the development of colitis-associated cancer by up-regulating colonic mucosal cell proliferation.


Asunto(s)
Antígenos de Neoplasias/fisiología , Moléculas de Adhesión Celular/fisiología , Neoplasias Colorrectales/fisiopatología , Proteínas de Neoplasias/fisiología , Animales , Peso al Nacer , Moléculas de Adhesión Celular/deficiencia , Colitis Ulcerosa/inducido químicamente , Colitis Ulcerosa/complicaciones , Colitis Ulcerosa/patología , Colon/patología , Neoplasias Colorrectales/etiología , Neoplasias Colorrectales/patología , Sulfato de Dextran , Dimetilhidrazinas , Modelos Animales de Enfermedad , Genes ras/genética , Crecimiento , Mucosa Intestinal/patología , Antígeno Ki-67/metabolismo , Ratones , Ratones Noqueados , Mutación , Proteínas de Neoplasias/deficiencia , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/métodos
13.
J Chem Phys ; 133(10): 104301, 2010 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-20849166

RESUMEN

We find that the most stable fullerene isomers, C(70)-C(94), form efficiently in close-to central collisions between keV atomic ions and weakly bound clusters of more than 15 C(60)-molecules. We observe extraordinarily high yields of C(70) and marked preferences for C(78) and C(84). Larger even-size carbon molecules, C(96)-C(180), follow a smooth log-normal (statistical) intensity distribution. Measurements of kinetic energies indicate that C(70)-C(94) mainly are formed by coalescence reactions between small carbon molecules and C(60), while C(n) with n≥96 are due to self-assembly (of small molecules) and shrinking hot giant fullerenes.


Asunto(s)
Fulerenos/química , Iones/química , Cinética , Estereoisomerismo , Termodinámica
14.
Clin Exp Immunol ; 155(1): 16-20, 2009 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19016805

RESUMEN

The regenerating gene (Reg) was originally isolated from regenerating rat pancreatic islets and revealed recently to constitute a multi-gene family in humans. REG Ialpha protein is known to be overexpressed not only in various human inflammatory diseases but also in various experimental models of inflammation in animal tissues. However, its involvement in pathophysiology of the minor salivary gland (MSG) is not clear. We investigated REG Ialpha expression in the MSG of patients with primary Sjögren's syndrome (SS) and assessed its role in ductal epithelial cell proliferation in such tissues. Lip biopsy specimens were obtained from 40 patients with primary SS and examined using immunohistochemistry for REG Ialpha protein, Ki67 and single-strand DNA (ssDNA). The relationships among clinicopathological factors and expression of REG Ialpha protein, Ki67 and ssDNA in the MSG were then analysed. REG Ialpha protein was expressed rarely in ductal epithelial cells of the normal MSG but was apparently overexpressed in those of patients with SS. The labelling indices for both Ki67 and ssDNA in the ductal cells of the MSGs were significantly higher in SS patients than in controls. Moreover, these labelling indices were significantly higher in REG Ialpha-positive than in negative SS patients. REG Ialpha protein may play a role in the regeneration of ductal epithelial cells in the MSGs of patients with SS.


Asunto(s)
Células Epiteliales/fisiología , Litostatina/análisis , Regeneración/fisiología , Conductos Salivales/fisiología , Glándulas Salivales Menores , Síndrome de Sjögren/patología , Adolescente , Adulto , Anciano , Biomarcadores/análisis , División Celular/fisiología , ADN de Cadena Simple/análisis , Células Epiteliales/metabolismo , Células Epiteliales/patología , Femenino , Humanos , Inmunohistoquímica , Antígeno Ki-67/análisis , Litostatina/metabolismo , Masculino , Persona de Mediana Edad , Conductos Salivales/metabolismo , Conductos Salivales/patología , Síndrome de Sjögren/metabolismo , Adulto Joven
16.
Clin Nephrol ; 71(5): 508-13, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-19473610

RESUMEN

BACKGROUND: Diabetes mellitus (DM) and deficiency in n-3 long-chain polyunsaturated fatty acids (n-3 LCPUFAs) are known to increase the incidence of cardiovascular disease (CVD). However, it has not yet been reported whether n-3 LCPUFAs are related to arteriosclerosis in patients under long-term hemodialysis (HD). METHODS: Pulse wave velocity from the brachium to the ankle (baPWV) was measured as a marker of arteriosclerosis with a volume-plethysmographic apparatus in 147 long-term HD patients (non-diabetic (non-DM): 51 males/42 females, 62 +/- 14 y; and DM: 33 males/21 females, 67 +/- 9 y). The fatty acid composition of the total phospholipid fraction from washed RBCs was analyzed by gas chromatography. Analyses were adjusted for age, sex, diastolic blood pressure, pulse, body mass index, duration of HD treatment, smoking status, LDL/HDL-cholesterol ratios and diabetes mellitus (DM). RESULTS: The mean baPWV was 18.9 +/- 5.2 and 23.7 +/- 6.3 m/s in non-DM and DM patients, respectively. The mean baPWV in DM patients was significantly higher than that of non-DM patients after adjustment (p = 0.0002). Multiple regression analysis showed that there was a significant inverse association between baPWV and docosahexaenoic acid (DHA) levels (p = 0.017) and DHA/arachidonic acid (AA) ratios (p = 0.012) in RBC in non-DM patients after adjustment but not in DM patients. CONCLUSIONS: We suggest that n-3 LCPUFAs may be a negative risk factor of CVD also in non-DM HD patients. In DM patients the effects of n-3 PUFAs on the vascular system became undetectable probably because DM overwhelmingly affected PWV. Further studies in a prospective manner are necessary.


Asunto(s)
Aterosclerosis/fisiopatología , Arteria Braquial/fisiología , Diabetes Mellitus/sangre , Ácidos Grasos Omega-3/sangre , Flujo Pulsátil/fisiología , Diálisis Renal/métodos , Anciano , Aterosclerosis/sangre , Aterosclerosis/epidemiología , Colesterol/sangre , Cromatografía de Gases , Cromatografía en Capa Delgada , Diabetes Mellitus/terapia , Femenino , Estudios de Seguimiento , Humanos , Incidencia , Japón/epidemiología , Fallo Renal Crónico/sangre , Fallo Renal Crónico/fisiopatología , Fallo Renal Crónico/terapia , Masculino , Persona de Mediana Edad , Pletismografía , Pronóstico , Factores de Riesgo , Factores de Tiempo
17.
J Chem Phys ; 131(1): 014301, 2009 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-19586099

RESUMEN

We present a detailed study of the electronic structure and the stability of C(60) dianions in the gas phase. Monoanions were extracted from a plasma source and converted to dianions by electron transfer in a Na vapor cell. The dianions were then stored in an electrostatic ring, and their near-infrared absorption spectrum was measured by observation of laser induced electron detachment. From the time dependence of the detachment after photon absorption, we conclude that the reaction has contributions from both direct electron tunneling to the continuum and vibrationally assisted tunneling after internal conversion. This implies that the height of the Coulomb barrier confining the attached electrons is at least approximately 1.5 eV. For C(60)(2-) ions in solution electron spin resonance measurements have indicated a singlet ground state, and from the similarity of the absorption spectra we conclude that also the ground state of isolated C(60)(2-) ions is singlet. The observed spectrum corresponds to an electronic transition from a t(1u) lowest unoccupied molecular orbital (LUMO) of C(60) to the t(1g) LUMO+1 level. The electronic levels of the dianion are split due to Jahn-Teller coupling to quadrupole deformations of the molecule, and a main absorption band at 10,723 cm(-1) corresponds to a transition between the Jahn-Teller ground states. Also transitions from pseudorotational states with 200 cm(-1) and (probably) 420 cm(-1) excitation are observed. We argue that a very broad absorption band from about 11,500 cm(-1) to 13,500 cm(-1) consists of transitions to so-called cone states, which are Jahn-Teller states on a higher potential-energy surface, stabilized by a pseudorotational angular momentum barrier. A previously observed, high-lying absorption band for C(60)(-) may also be a transition to a cone state.

18.
Lett Appl Microbiol ; 49(6): 715-20, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19818009

RESUMEN

AIMS: Human bifidobacteria are more sensitive to external environmental factors than animal bifidobacteria, and it is difficult to ensure their stable survival in yogurt. The purpose of this investigation was to observe the survival of human bifidobacteria in yogurts produced under various production conditions. METHODS: Frozen or lyophilized bifidobacteria starters containing Bifidobacterium longum BB536 originally isolated from an infant, and commercial lyophilized yogurt starters were used for yogurt preparation. After producing yogurts under various conditions, the survival of bifidobacteria in these yogurts over various storage periods was observed. RESULTS: Although there were some differences in bifidobacterial survival in yogurt between various production conditions, more than 1.0 x 10(7) CFU g(-1) of Bif. longum survived in yogurt after 35 days' storage at 5 degrees C. Lower fermentation temperature (37 degrees C) and inclusion of Lactococcus lactis in the starter significantly (P < 0.05) improved survival of Bif. longum in the yogurt. CONCLUSION: In this investigation, the human bifidobacterial strain Bif. longum survived adequately in yogurt, although the fermentation temperature and starter composition affect bifidobacterial survival. SIGNIFICANCE AND IMPACT OF THE STUDY: This investigation indicates that stable probiotic yogurt using human bifidobacteria can be produced by choosing optimal production conditions.


Asunto(s)
Bifidobacterium/crecimiento & desarrollo , Microbiología de Alimentos , Probióticos , Yogur/microbiología , Bifidobacterium/aislamiento & purificación , Recuento de Colonia Microbiana , Fermentación , Humanos , Lactococcus lactis , Temperatura
19.
Radiat Prot Dosimetry ; 184(3-4): 294-297, 2019 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-31330016

RESUMEN

This paper describes our trial experience of the use of high radiation area for radiation education. We used environmental samples collected from the high radiation area in Fukushima prefecture and India, for the practice of radiation measurement and health risk assessment in Nagasaki University Medical School. We also carried out the field monitoring seminar for students in the existing exposure areas in Tottori prefecture and the Yamakiya observatory in Fukushima. Although the evaluation of educational effectiveness is still underway, both types of education appeared attractive for the students mostly due to the exposure from natural environment in our real life which was not achieved by using an artificial radiation source in a classroom.


Asunto(s)
Radiación de Fondo , Accidente Nuclear de Fukushima , Monitoreo de Radiación/métodos , Radiobiología/educación , Medición de Riesgo/métodos , Contaminantes Radiactivos del Suelo/análisis , Monitoreo del Ambiente , Humanos , India , Japón , Plantas de Energía Nuclear
20.
Br J Cancer ; 98(10): 1682-9, 2008 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-18443596

RESUMEN

Although stromal cell-derived factor (SDF)-1 alpha and its receptor CXCR4 are experimentally suggested to be involved in tumorigenicity, the clinicopathological significance of their expression in human disease is not fully understood. We examined SDF-1 alpha and CXCR4 expression in colorectal cancers (CRCs) and their related lymph nodes (LNs), and investigated its relationship to clinicopathological features. Specimens of 60 primary CRCs and 27 related LNs were examined immunohistochemically for not only positivity but also immunostaining patterns for SDF-1 alpha and CXCR4. The relationships between clinicopathological features and SDF-1 alpha or CXCR4 expression were then analysed. Stromal cell-derived factor-1 alpha and CXCR4 expression were significantly associated with LN metastasis, tumour stage, and survival of CRC patients. Twenty-nine of 47 CXCR4-positive CRCs (61.7%) showed clear CXCR4 immunoreactivity in the nucleus and a weak signal in the cytoplasm (nuclear type), whereas others showed no nuclear immunoreactivity but a diffuse signal in the cytoplasm and at the plasma membrane (cytomembrane type). Colorectal cancer patients with nuclear CXCR4 expression showed significantly more frequent LN metastasis than did those with cytomembrane expression. Colorectal cancer patients with nuclear CXCR4 expression in the primary lesion frequently had cytomembrane CXCR4-positive tumours in their LNs. In conclusion, expression of SDF-1 alpha and nuclear CXCR4 predicts LN metastasis in CRCs.


Asunto(s)
Biomarcadores de Tumor/análisis , Quimiocina CXCL12/análisis , Neoplasias Colorrectales/química , Neoplasias Colorrectales/patología , Ganglios Linfáticos/química , Ganglios Linfáticos/patología , Receptores CXCR4/análisis , Adulto , Anciano , Anciano de 80 o más Años , Western Blotting , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Inmunohistoquímica , Metástasis Linfática , Masculino , Persona de Mediana Edad , Análisis Multivariante , Estadificación de Neoplasias , Modelos de Riesgos Proporcionales , Análisis de Supervivencia
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