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1.
Clin Radiol ; 75(7): 543-551, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32209236

RESUMEN

AIM: To investigate whether contrast-enhanced (CE)-magnetic resonance imaging (MRI) improves identification of implantation site of ectopic pregnancy. MATERIALS AND METHODS: This retrospective study enrolled 63 patients in whom implantation sites had been confirmed at histopathology. Two expert radiologists for gynaecological imaging and two inexpert radiologists independently reviewed non-CE MRI and a combination of non-CE and CE-MRI (non-CE+CE-MRI), then determined implantation site with a confidence level. The following MRI features were also evaluated: extrauterine gestational sac (GS)-like structure (shape, signal intensities at T1-weighted imaging [WI], T2WI, and diffusion-weighted imaging [DWI], presence of the three rings appearance, and distinct low intensity areas at T2WI, presence of tree or dot-like components, degree of contrast enhancement), fallopian tube (dilatation, dilatation with haematoma, degree of contrast enhancement, enhanced components within the tube), and ascites. These findings were compared for non-CE and non-CE+CE-MRI data, and for expert and inexpert groups. RESULTS: The expert group identified implantation sites correctly in 58/63 (92%) cases for non-CE and non-CE+CE-MRI. In the inexpert group, the correct identification was improved from 54/63 (86%) using non-CE MRI to 58/63 (92%) using non-CE+CE-MRI, but was not significant (p=0.29). In comparison between non-CE and non-CE+CE-MRI, dilation of the fallopian tubes was observed more frequently (p=0.004) and the confidence level was elevated significantly in the non-CE+CE-MRI (p<0.0001) in the inexpert group. Intergroup comparison revealed that confidence level was significantly higher in the expert group than in the inexpert group using non-CE MRI (p<0.0001), although the difference was not significant at non-CE+CE MRI (p=0.49). CONCLUSION: CE-MRI did not significantly improve correct identification of ectopic pregnancy implantation sites, although the addition of contrast enhancement did enable inexpert radiologists to diagnose confidently.


Asunto(s)
Imagen por Resonancia Magnética/métodos , Embarazo Ectópico/diagnóstico por imagen , Adulto , Medios de Contraste , Imagen de Difusión por Resonancia Magnética/métodos , Femenino , Humanos , Embarazo , Embarazo Ectópico/diagnóstico , Estudios Retrospectivos , Adulto Joven
2.
Dis Esophagus ; 29(6): 598-602, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26338205

RESUMEN

Historically, total pharyngolaryngectomy with total esophagectomy has been the standard radical surgical treatment for synchronous cancer of the thoracoabdominal esophagus and pharyngolaryngeal region, and for cancer of the cervical esophagus that has invaded as far as the thoracic esophagus. Although definitive chemoradiotherapy that enables preservation of the larynx has often been the first choice of treatment for cancers involving the cervical esophagus, total pharyngolaryngectomy with total esophagectomy is required as a salvage therapy for cases involving failure of complete remission or locoregional recurrence after chemoradiotherapy. However, salvage esophageal surgery after definitive high-dose chemoradiotherapy is generally associated with high morbidity and mortality. The aim of this study was to examine the short-term outcome of salvage total pharyngolaryngectomy with total esophagectomy. From 2001 to 2014, nine patients underwent salvage total pharyngolaryngectomy with total esophagectomy at the Department of Gastroenterological Surgery, Nagoya University. The mortality and morbidity rates were high at 22% and 89%, respectively. Four patients (44%) developed tracheal necrosis, which in two patients eventually led to lethal hemorrhage. Salvage total pharyngolaryngectomy with total esophagectomy is an uncommon and highly demanding surgical procedure that should be carefully planned and conducted in selected centers of excellence. Measures must be taken to preserve the tracheal blood supply, thus avoiding fatal complications.


Asunto(s)
Carcinoma de Células Escamosas/terapia , Neoplasias Esofágicas/terapia , Esofagectomía , Neoplasias de Cabeza y Cuello/terapia , Neoplasias Laríngeas/terapia , Laringectomía , Neoplasias Primarias Múltiples/terapia , Neoplasias Faríngeas/terapia , Faringectomía , Anciano , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Quimioradioterapia , Cisplatino/administración & dosificación , Carcinoma de Células Escamosas de Esófago , Fluorouracilo/administración & dosificación , Humanos , Masculino , Persona de Mediana Edad , Terapia Neoadyuvante , Estudios Retrospectivos , Terapia Recuperativa , Carcinoma de Células Escamosas de Cabeza y Cuello , Resultado del Tratamiento
3.
Int J Oral Maxillofac Surg ; 52(6): 621-629, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36470693

RESUMEN

The aim of this study was to assess changes in the quality of life and psychological distress of patients with tongue cancer undergoing total/subtotal glossectomy (TG) or extended hemiglossectomy (HG) and free flap transfer. Differences between the two groups were compared using the Short Form 8-Item Health Survey (SF-8) and Hospital Anxiety and Depression Scale (HADS). Of the 43 patients with tongue cancer, 24 (56%) underwent TG and 19 (44%) underwent HG. The general health and social functioning scores in the SF-8 and depression in the HADS were significantly worse in the TG group than in the HG group at 12 months after surgery, indicating that patients in the TG group may experience social isolation and psychological distress, and have difficulty in employability even 12 months after surgery. In contrast, all items of the SF-8 in the HG group were nearly equal to those in the general population. Due to the extensive psychological impact on patients with tongue cancer who are planned for an extended resection, curative surgery with free flap transfer and multidisciplinary psychiatric support are essential to improve quality of life and manage psychological distress.


Asunto(s)
Colgajos Tisulares Libres , Procedimientos de Cirugía Plástica , Distrés Psicológico , Neoplasias de la Lengua , Humanos , Glosectomía , Neoplasias de la Lengua/cirugía , Calidad de Vida , Antebrazo , Lengua/cirugía
4.
Clin Exp Immunol ; 164(3): 417-27, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21413942

RESUMEN

While Gr1(+)CD11b(+) cells are known to regulate immune responses and accumulate in most cancer tissues, the function of Gr1(+)CD11b(+) cells in inflammation is poorly understood. We investigated the role of Gr1(+)CD11b(+) cells in a dextran sulphate sodium (DSS)-treated mouse model of ulcerative colitis (UC). C57BL/6 mice were treated with 2% DSS in drinking water for 5 days. Disease progression and recovery were assessed by body weight, disease activity index score (DAI) score and colon length. Splenic Gr1(+)CD11b(+) cell number was greatly increased during the recovery phase of DSS-induced colitis. DSS-derived splenic Gr1(+)CD11b(+) cells were administered intravenously to recipient (C57BL/6) mice during the early phase of DSS treatment. The transplanted splenic DSS-induced Gr1(+)CD11b(+) cells improved DSS-induced colitis and promoted efficient colonic mucosal healing. We found that the CD11b(+) single positive cells increased in the course of DSS-induced colitis in lamina propria. The transplantation of splenic Gr1(+)CD11b(+) cells induced feedback suppression of myeloid-lineage cell development. Namely, the transplantation of splenic Gr1(+)CD11b(+) cells greatly suppressed the migration of CD11b(+) single positive cells to the lamina propria. Further, transplantation of Gr-1(+)CD11b(+) cells greatly suppressed the increase of the same population, especially during the late phase of DSS colitis both in spleen and bone marrow.


Asunto(s)
Trasplante de Células , Colitis Ulcerosa/inmunología , Colitis Ulcerosa/terapia , Colon/patología , Bazo/metabolismo , Animales , Antígeno CD11b/biosíntesis , Recuento de Células , Diferenciación Celular , Movimiento Celular , Células Cultivadas , Colitis Ulcerosa/inducido químicamente , Colitis Ulcerosa/fisiopatología , Sulfato de Dextran/administración & dosificación , Modelos Animales de Enfermedad , Progresión de la Enfermedad , Humanos , Ratones , Ratones Endogámicos C57BL , Receptores de Superficie Celular/biosíntesis , Bazo/inmunología , Bazo/patología
5.
Int J Immunogenet ; 38(3): 249-54, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21385326

RESUMEN

Sudden sensorineural hearing loss (SSNHL) and Ménière's disease are the most common inner ear diseases in which the causes are unknown. As recent magnetic resonance imaging has demonstrated disruption of the blood-labyrinth barrier in these inner ear diseases, inflammatory reaction associated with increased permeability of the blood vessels may be involved. The genotypes of interleukin 1A (IL1A) (-889C/T; rs1800587) and interleukin 1B (IL1B) (-511C/T; rs16944) were determined using an allele-specific primer-polymerase chain reaction method in 72 patients with SSNHL, 68 patients with Ménière's disease, and 2202 control subjects living almost in the same area as the patients. A significantly higher prevalence of the IL1A-889T allele was observed in SSNHL and Ménière's disease compared with controls, although no significant difference in distribution of IL1B-511C/T genotypes was observed between the patients and controls. Adjusted odd ratios for SSNHL and Ménière's disease risks in the -889TT genotypes were 25.89 (95% confidence interval (CI) 12.19-54.98) and 18.20 (95% CI 7.80-42.46), respectively, after age and gender were taken as moderator variables. Our results suggested that IL1A is closely associated with susceptibility of SSNHL and Ménière's disease.


Asunto(s)
Pérdida Auditiva Súbita/genética , Interleucina-1/genética , Enfermedad de Meniere/genética , Polimorfismo Genético , Adulto , Anciano , Anciano de 80 o más Años , Alelos , Femenino , Frecuencia de los Genes/genética , Predisposición Genética a la Enfermedad , Genotipo , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven
6.
Int J Oral Maxillofac Surg ; 50(3): 316-322, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32826125

RESUMEN

In the head and neck region, preoperative evaluation of the free flap volume is challenging. The current study validated preoperative three-dimensional (3D) virtual surgical simulation for soft tissue reconstruction by assessing flap volume and evaluated fat and muscle volume changes at follow-up in 13 head and neck cancer patients undergoing anterolateral craniofacial resection. Patients received 3D virtual surgical simulation, and the volume of the planned defects was estimated by surgical simulation. Following en bloc resection of the tumor, the defect in the skull base was covered using a rectus abdominis myocutaneous flap. Following surgery, computed tomography scans were acquired at day 1 and at 6 and 12 months. Virtual planned defect was on average 227 ml (range, 154-315) and was 10% smaller than the actual flap volume in patients without skin involvement of the tumor. Between day 1 and 12 months post-surgery, the volume of fat and muscle tissue in the free flap dropped by 9% and 58%, respectively. Our results indicate that 3D virtual surgical simulation provides essential information in determining the accurate volume of the required free flap for surgical defect repair and may thus help improve surgical planning and functional and esthetic outcome.


Asunto(s)
Colgajos Tisulares Libres , Neoplasias de Cabeza y Cuello , Colgajo Miocutáneo , Procedimientos de Cirugía Plástica , Estética Dental , Estudios de Factibilidad , Neoplasias de Cabeza y Cuello/diagnóstico por imagen , Neoplasias de Cabeza y Cuello/cirugía , Humanos
7.
J Nutr Health Aging ; 23(3): 251-255, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30820513

RESUMEN

AIM: Phase angle (PhA) can be determined through bioelectrical impedance analysis and is a unique variable for skeletal muscle. The objective of this study was to evaluate the relationship between PhA and muscle mass/quality in older adults. In addition, we attempted to determine the cutoff value of PhA for poor muscle function. METHODS: Community-dwelling Japanese older men (n=285, 81.1±7.1 years) and women (n=724, 80.4±6.8 years) participated in this study and were classified into four groups based on the Asian Working Group for Sarcopenia (normal, presarcopenia, dynapenia, and sarcopenia). We measured PhA using bioelectrical impedance analysis, muscle quantity and quality indicators using ultrasonography, muscle strength, and physical performance and compared them in four groups. We also tried to determine the cutoff value of PhA for poor muscle function. RESULTS: We found a significant difference in PhA among the four groups in men (P<0.05), and the dynapenia (3.61±0.75°) and sarcopenia groups (3.40±0.74°) showed significantly lower values than the normal group (4.50±0.86°) (P<0.05), but not the presarcopenia group (4.12±0.85°). In women, a significant difference was also observed among the four groups (P<0.05), and the dynapenia (3.41±0.65°) and sarcopenia groups (3.31±0.66°) showed significantly lower measures than the normal group (4.14±0.71°) (P<0.05), but not the presarcopenia group (4.07±0.51°). The receiver-operating characteristic curve analysis indicated the best cutoff value of PhA (men: 4.05°, women: 3.55°) to discriminate sarcopenia and dynapenia from normal and presarcopenia. CONCLUSION: These findings suggest that PhA is a useful indicator for muscle function.


Asunto(s)
Impedancia Eléctrica/uso terapéutico , Fuerza Muscular/fisiología , Sarcopenia/fisiopatología , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino
8.
J Nutr Health Aging ; 22(7): 819-823, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30080226

RESUMEN

BACKGROUND: Although several previous studies have found benefits for amino acid supplementation in terms of muscle function, the role of plasma amino acid concentrations on sarcopenia are not well addressed yet. OBJECTIVE: The aim of this study was to compare the amino acid concentrations at each stage of sarcopenia (normal, pre-sarcopenia, dynapenia, and sarcopenia) in community-dwelling older Japanese adults. SETTING AND SUBJECTS: Community-dwelling older Japanese women (n=232, 79.4±7.0 years) participated in this study. MEASUREMENTS: We measured plasma amino acid concentrations, 5-m walking speed, grip strength, and skeletal muscle mass using a bioelectrical impedance data acquisition system and compared them among participants at each stage of sarcopenia. RESULTS: The proportions of normal, pre-sarcopenia, dynapenia, and sarcopenia patients were 40.5% (n=94), 12.1% (n=28), 26.3% (n=61), and 21.1% (n=49), respectively. Significant differences were observed for concentrations of leucine, branched-chain amino acid (BCAAs), and essential amino acid (EAAs) among the four groups (p<0.05), and the dynapenia and sarcopenia groups showed significantly lower concentrations of leucine than the normal group (p<0.05). CONCLUSIONS: This study indicated a positive relationship between plasma leucine, BCAA and EAA concentrations and muscle function. A longitudinal study is needed to determine the causal relationship between leucine/BCAA concentrations and muscle function.


Asunto(s)
Aminoácidos de Cadena Ramificada/sangre , Aminoácidos Esenciales/sangre , Fuerza de la Mano/fisiología , Fuerza Muscular/fisiología , Músculo Esquelético/fisiología , Sarcopenia/fisiopatología , Anciano , Impedancia Eléctrica , Femenino , Humanos , Vida Independiente , Japón , Estudios Longitudinales , Caminata/fisiología
9.
J Laryngol Otol ; 130(10): 914-922, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-27604559

RESUMEN

OBJECTIVES: To verify the effectiveness and safety of the addition of adipose-derived regenerative cells to autologous fat injection therapy. METHODS: Unilateral vocal fold paralysis models were made by cutting the right recurrent laryngeal nerve in two pigs. At day 30, 0.5 ml adipose-derived regenerative cells mixed with 1 ml autologous fat was injected into the right vocal fold of one pig, with the other receiving 0.5 ml Ringer's solution mixed with 1 ml autologous fat. At day 120, fibrescopy, laser Doppler flowmeter, computed tomography, vocal function evaluation and histological assessment were conducted. RESULTS: Although histological assessment revealed atrophy of the thyroarytenoid muscle fibre in both pigs, there was remarkable hypertrophy of the thyroarytenoid muscle fibre in the area surrounding the adipose-derived regenerative cells injection site. CONCLUSION: The addition of a high concentration of adipose-derived regenerative cells to autologous fat injection therapy has the potential to improve the treatment outcome for unilateral vocal fold paralysis.


Asunto(s)
Adipocitos/trasplante , Tejido Adiposo/trasplante , Trasplante de Células Madre/métodos , Parálisis de los Pliegues Vocales/terapia , Adipocitos/citología , Tejido Adiposo/citología , Animales , Modelos Animales de Enfermedad , Hipertrofia/etiología , Músculos Laríngeos/patología , Laringe/patología , Atrofia Muscular/etiología , Proyectos Piloto , Porcinos , Trasplante Autólogo , Resultado del Tratamiento , Pliegues Vocales/patología
10.
Exp Hematol ; 28(8): 950-60, 2000 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10989196

RESUMEN

Intrathymic T-cell differentiation is characterized by two selection events: positive and negative selection. It has been shown that thymic epithelial cells in the cortex are involved in the positive selection, while macrophages and dendritic cells, derived from hemopoietic stem cells, are involved in the negative selection. Here we investigate whether donor-derived bone marrow stromal cells can migrate into the thymus and participate there in positive selection after bone marrow transplantation plus bone grafts (to recruit bone marrow stromal cells). Allogeneic bone marrow transplantation with or without bone grafts was carried out in the [C57BL/6-->C3H] combination. Fluorescence-activated cell sorter analyses of recipient thymic adherent cells showed that donor-type bone marrow stromal cells exist in the thymus of mice that received bone marrow plus bone grafts but not in the mice that received bone marrow cells alone. Histological examination using confocal microscopy also confirmed the existence of donor-type stromal cells in the thymus of mice that received bone marrow cells plus bones. Both T-cell proliferation and plaque-forming cell assays indicated that the T cells of such mice show donor-type major histocompatibility complex-restriction. These findings strongly suggest that stromal cells can migrate from the bone marrow to the thymus, where they participate in the positive selection of thymocytes.


Asunto(s)
Células de la Médula Ósea/citología , Trasplante de Médula Ósea , Trasplante Óseo , Células del Estroma/citología , Células del Estroma/fisiología , Timo/citología , Animales , Células Presentadoras de Antígenos/inmunología , Antígenos/inmunología , Adhesión Celular , Movimiento Celular , Antígenos H-2/inmunología , Humanos , Activación de Linfocitos , Complejo Mayor de Histocompatibilidad , Ratones , Ratones Endogámicos C3H , Ratones Endogámicos C57BL , Microscopía Confocal , Linfocitos T/inmunología , Donantes de Tejidos
11.
Neuroscience ; 290: 18-30, 2015 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-25613686

RESUMEN

Nicotinic acetylcholine receptors (nAChRs) are distributed widely in the central nervous system and play important roles in higher brain functions, including learning, memory, and recognition. However, functions of the cholinergic system in spinal motoneurons remain poorly understood. In this study, we investigated the actions of presynaptic and postsynaptic nAChRs in spinal ventral horn neurons by performing whole-cell patch-clamp recordings on lumbar slices from male rats. The application of nicotine or acetylcholine generated slow inward currents and increased the frequency and amplitude of spontaneous excitatory postsynaptic currents (sEPSCs). Slow inward currents by acetylcholine or nicotine were not inhibited by tetrodotoxin (TTX) or glutamate receptor antagonists. In the presence of TTX, the frequency and amplitude of miniature excitatory postsynaptic currents (mEPSCs) were also increased by acetylcholine or nicotine. A selective α4ß2 nicotinic receptor antagonist, dihydro-ß-erythroidine hydrobromide (DhßE), significantly decreased nicotine-induced inward currents without affecting the enhancement of sEPSCs and mEPSCs. In addition, a selective α7 nicotinic receptor antagonist, methyllycaconitine, did not affect either nicotine-induced inward currents or the enhancement of sEPSCs and mEPSCs. These results suggest that α4ß2 AChRs are localized at postsynaptic sites in the spinal ventral horn, non-α4ß2 and non-α7 nAChRs are located presynaptically, and nAChRs enhance excitatory synaptic transmission in the spinal ventral horn.


Asunto(s)
Células del Asta Anterior/fisiología , Receptores Nicotínicos/metabolismo , Sinapsis/fisiología , Transmisión Sináptica/fisiología , Animales , Células del Asta Anterior/efectos de los fármacos , Potenciales Postsinápticos Excitadores/efectos de los fármacos , Potenciales Postsinápticos Excitadores/fisiología , Región Lumbosacra , Masculino , Potenciales Postsinápticos Miniatura/efectos de los fármacos , Potenciales Postsinápticos Miniatura/fisiología , Técnicas de Placa-Clamp , Ratas Sprague-Dawley , Sinapsis/efectos de los fármacos , Transmisión Sináptica/efectos de los fármacos , Técnicas de Cultivo de Tejidos
12.
Immunobiology ; 197(1): 31-43, 1997 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-9241529

RESUMEN

The male (NZW x BXSB)F1 (W/BF1) mouse, a murine model for autoimmune diseases, shows hepatosplenomegaly with lymphoid cell infiltration in the liver by 20 weeks of age. The majority of infiltrating cells are T cells, B cells and plasma cells, as seen in autoimmune hepatitis. Together with the increase in serum glutamate pyruvate transaminase (GPT) levels, anti-dsDNA antibody (Ab) and circulating immune complex (CIC) levels increase with age. These findings are compatible with those of autoimmune hepatitis in humans. In addition, a unique finding in this mouse is the accumulation of CD4+ Mac-1+ Class II+ cells in the sinusoidal space. The cells have the capacity to proliferate and differentiate into macrophages in vitro, indicating that they are the precursors of macrophages. This W/BF1 mouse provides a useful tool for not only analyzing the pathogenesis of autoimmune hepatitis but also establishing a new therapeutic strategy for it. In addition, we discuss the significance of the appearance of abnormal cells in autoimmune-prone mice.


Asunto(s)
Enfermedades Autoinmunes/etiología , Antígenos CD4/análisis , Hepatitis Animal/inmunología , Antígenos de Histocompatibilidad Clase II/análisis , Hígado/inmunología , Antígeno de Macrófago-1/análisis , Animales , Enfermedades Autoinmunes/inmunología , Enfermedades Autoinmunes/patología , Diferenciación Celular/inmunología , Movimiento Celular/inmunología , Separación Celular , Células Clonales , Cruzamientos Genéticos , Modelos Animales de Enfermedad , Citometría de Flujo , Hepatitis Animal/etiología , Hepatitis Animal/patología , Inmunofenotipificación , Hígado/patología , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos NZB
13.
Immunobiology ; 202(3): 213-25, 2000 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11045658

RESUMEN

The ALY-alyl/aly mouse is a new and unique animal model of primary immunodeficiency with autosomal recessive inheritance. The ALY mouse is devoid of superficial and profound lymph nodes and Peyer's patches. Furthermore, the lymphoid follicles and marginal zones are not clearly identified in the spleen. In addition to these structural defects, in the present study, we show that some B subpopulations are defective. Firstly, the thymic B lymphocytes are very rare. Secondly, the B220hi sIghi B subpopulation in the bone marrow is not detected as a clear cluster on FACS analyses. Thirdly, the B220 slg+ cells in the bone marrow are very rare in both ALY-aly/aly and ALY-alyl+ mice. By contrast, the NK activity is normal. Taken together, the ALY mouse is an invaluable model to elucidate the immunological networks between the lymphoid structures (lymph nodes, Peyer's patches, lymphoid follicles, etc.) and functions.


Asunto(s)
Síndromes de Inmunodeficiencia/patología , Ganglios Linfáticos/inmunología , Ganglios Linfáticos Agregados/inmunología , Animales , Linfocitos B/inmunología , Células de la Médula Ósea/inmunología , Síndromes de Inmunodeficiencia/inmunología , Células Asesinas Naturales/inmunología , Ratones , Ratones Endogámicos BALB C , Ratones Mutantes , Bazo/patología , Timo/citología , Timo/inmunología
14.
J Biochem ; 114(6): 761-2, 1993 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-8138527

RESUMEN

New crystals of a blue copper protein, pseudoazurin from denitrifier Achromobacter cycloclastes IAM1013, have been obtained by means of vapor diffusion with ammonium sulfate as a precipitant at pH 6.0 and 4 degrees C. The crystals belong to the orthorhombic system, space group P2(1)2(1)2(1), with unit cell dimensions of a = 56.69(2), b = 61.53(2), and c = 30.20(1) A. The asymmetric unit includes one molecule of pseudoazurin with a Vm value of 2.04 A3/Da. The crystals are so stable against X-ray irradiation that a complete data set up to 1.54 A has been collected using a single native crystal. Solution of the structure was performed by means of the Patterson search techniques, and the current crystallographic R-factor is 17.5% at 3.0 A resolution. Refinement at higher resolution is in progress.


Asunto(s)
Alcaligenes/química , Azurina/análogos & derivados , Azurina/química , Azurina/aislamiento & purificación , Cristalografía por Rayos X
15.
Neurol Res ; 11(3): 165-8, 1989 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-2573852

RESUMEN

To ascertain the critical thresholds of intracranial pressure (ICP) and cerebral perfusion pressure (CPP) for cerebral circulation and brain function, the extra- and intracranial haemodynamics and electrical brain responses were evaluated noninvasively with Doppler ultrasonography and multimodality evoked potentials (MEP's) in 50 patients with severe head injury. Both extra- and intracranial blood flow velocities changed monotonically depending on the changes in ICP and CPP. They were decreased when ICP increased to 20-30 mmHg and when CPP decreased to 40-50 mmHg. The changes in elasticity index of the pulse wave of the common carotid artery was proportional to those of blood flow velocities. The frequency and degree of abnormalities of MEP's were proportionally increased with the rise of ICP and reduction of CPP. When ICP increased to higher than 31 mmHg, MEP's were classified as moderately or severely abnormal in more than 76% of the recordings. These results indicate that noninvasive study by use of Doppler ultrasonography and MEP's can provide valuable information on critical brain ischaemia and brain dysfunction in patients with acute intracranial hypertension.


Asunto(s)
Lesiones Encefálicas/fisiopatología , Circulación Cerebrovascular , Presión Intracraneal , Ultrasonografía , Adolescente , Adulto , Anciano , Velocidad del Flujo Sanguíneo , Lesiones Encefálicas/diagnóstico , Humanos , Persona de Mediana Edad
16.
J Biosci Bioeng ; 87(2): 155-60, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-16232443

RESUMEN

The growth inhibition of Pyrococcus furiosus by acetic acid was stronger than that by hydrogen and could be described by a non-competitive inhibition model in which the inhibition constants of undissociated acetic acid, K(p) and n, were estimated to be 0.69 mM (25 mM total acetic acid at pH 6.5; pKa=4.96; 98 degrees C) and 1.0, respectively. In order to reduce the acetic acid inhibition, repeated-batch culturing was performed using a filtration module. This yielded 0.49 g of dry cells l(-1) after growth for 12 h after inoculation. It became impossible, however, to continue repeated-batch culturing manually because the time intervals for medium replacement became too short. In order to automatically maintain a low concentration of acetic acid, a perfusion culture was carried out in which medium feeding coupled to a pH-auxostat was performed. In this perfusion culture, it was possible to maintain the acetic acid concentration below 7.6 mM during exponential growth of P. furiosus, resulting in 1.8 g of dry cells l(-1) at 15 h after inoculation.

17.
J Biosci Bioeng ; 91(2): 153-8, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-16232967

RESUMEN

In a batch culture of Neocallimastix frontalis in a medium (pH 6.8) containing 8 g.l(-1) cellulose, the concentrations of the fermentation products and the cellulolytic and xylanolytic enzymes did not increase in comparison with those of cultures in a medium containing 4 g.l(-1) cellulose. Therefore, kinetic studies were performed to determine the effect that products such as acetate, formate, lactate and ethanol have in inhibiting the growth. The reduction of the specific growth rate by the fermentation products could be expressed by using a noncompetitive inhibition model, and it was found that at low concentrations, acetate was the strongest inhibitor among the inhibitory products studied. In order to reduce the inhibition by the fermentation products, a repeated batch culture was carried out whereby none of the fatty acids exceeded 50 mM. In this repeated batch culture, xylanase, endoglucanase, beta-glucosidase, and avicelase were continuously produced in the medium during cultivation, and 18200, 4550, 3790 and 129 IU g.l(-1) of these enzymes, respectively, were produced up to 20 d of culture.

18.
J Biosci Bioeng ; 90(6): 661-4, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-16232928

RESUMEN

By the addition of 150 mM acetate into a batch culture at an initial pH of 6.8, the production of 2,3-butanediol (BDL) by Paenibacillus polymyxa reached 248 mM, yielding 0.87 mol.mol(-1) glucose, where the ratio of acetate consumed to glucose consumed (A/C ratio) was calculated as 0.35 mol acetate mol(-1) glucose. Therefore, a fed-batch culture was carried out by feeding glucose and acetate at a ratio of 0.35 mol acetate mol(-1) glucose. In the fed-batch culture performed at pH 6.8, BDL production reached 637 mM, yielding 0.81 mol.mol(-1) glucose, although the A/C ratio was only 0.18 mol acetate mol(-1) glucose. By decreasing pH to 6.3 in the fed-batch culture, BDL production reached 566 mM, yielding 0.88 mol.mol(-1) glucose and the A/C ratio was 0.32 mol acetate mol(-1) glucose. The optical purity of BDL, which was expressed as enantiomeric excess, was retained at more than 98% of the (R, R)-stereoisomer at the end of culture, which was comparable to that without acetate addition.

19.
J Biosci Bioeng ; 87(5): 625-9, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-16232529

RESUMEN

The effect of the extracellular polymeric substance (EPS) derived from a marine photosynthetic bacterium, Rhodovulum sp., on the flocculation of kaolin is described. The amount of EPS obtained and its flocculating activity were highly dependent on the extraction temperature and duration: high flocculating activity was obtained at a relatively low temperature (30 degrees C) and long extraction time (60 min). The EPS was classified as a weak-anionic high-polymer group based on its pH profile, and its promoting effect on flocculation was dependent on the concentration of cationic ions and their valence. The relative influence of cations on the critical flocculating concentration (Cs,cr) followed the Schulze-Hardy rule for colloidal flocculation. This suggests that the promotion of flocculation by the additions of EPS and cations occurred as a result of the synergistic effect of the release of electrical repulsion by the cations and the formation of bridges between the EPS and the cations.

20.
J Biosci Bioeng ; 88(4): 410-5, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-16232636

RESUMEN

Removal of phosphorous compounds from the mud sediment of an oyster farm was carried out by a series of bio-processes under anaerobic conditions. Anaerobic acidogenic fermentation of a mud sediment suspension (200 g wet wt/l artificial sea water) was initially carried out. With the addition of vitamins such as thiamine, nicotinic acid and biotin, acidogenic fermentation was enhanced to yield acetic acid of approximately 2 g/l. Furthermore, approximately 20 mg/l of PO4(3-) (10% of total phosphorus on mud weight) and 5300 mg/l of COD(Cr) (82% of organic matter on mud weight) were released into the culture broth after fermentation for 7 d. The supernatant of this culture broth was used to cultivate Rhodobacter sphaeroides IL106, a denitrifying photosynthetic bacterium. After 4 d, 3.32 g/l of biomass containing carotenoid and ubiquinone was obtained, and COD(Cr) and acetic acid were reduced by 58% and 72%, respectively. In addition, PO4(3-) was reduced by 97%, suggesting that the removal of PO4(3-) from the mud sediment might be possible by combining anaerobic acidogenic fermentation with R. sphaeroides cultivation.

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