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1.
J Appl Microbiol ; 134(4)2023 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-37024272

RESUMEN

It is known that members of the bacterial genus Azospirillum can promote the growth of a great variety of plants, an ability harnessed by the industry to create bioproducts aimed to enhance the yield of economically relevant crops. Its versatile metabolism allows this bacterium to adapt to numerous environments, from optimal to extreme or highly polluted. The fact of having been isolated from soil and rhizosphere samples collected worldwide and many other habitats proves its remarkable ubiquity. Azospirillum rhizospheric and endophytic lifestyles are governed by several mechanisms, leading to efficient niche colonization. These mechanisms include cell aggregation and biofilm formation, motility, chemotaxis, phytohormone and other signaling molecules production, and cell-to-cell communication, in turn, involved in regulating Azospirillum interactions with the surrounding microbial community. Despite being infrequently mentioned in metagenomics studies after its introduction as an inoculant, an increasing number of studies detected Azospirillum through molecular tools (mostly 16S rRNA sequencing) as part of diverse, even unexpected, microbiomes. This review focuses on Azospirillum traceability and the performance of the available methods, both classical and molecular. An overview of Azospirillum occurrence in diverse microbiomes and the less-known features explaining its notorious ability to colonize niches and prevail in multiple environments is provided.


Asunto(s)
Azospirillum , ARN Ribosómico 16S/genética , ARN Ribosómico 16S/metabolismo , Azospirillum/genética , Azospirillum/metabolismo , Reguladores del Crecimiento de las Plantas/metabolismo , Plantas/microbiología , Transducción de Señal , Rizosfera , Raíces de Plantas/microbiología , Microbiología del Suelo
2.
Lett Appl Microbiol ; 74(4): 604-612, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-34967451

RESUMEN

The use of Azospirillum brasilense as a crop inoculant has increased in recent years. Thus, the compatibility of the inoculation technology with seed treatments using pesticides needs to be evaluated. In this study, we evaluated the effect of an insecticide and fungicide formulation on A. brasilense strain FP2 population by culturing and culture-independent approaches. In addition, we evaluated the impact of these pesticides on the ability of A. brasilense to promote plant growth by monitoring biometric traits (root and shoot dry mass and length) of wheat grown in Greenhouse conditions. Seed pesticide dressings, mainly fungicide, led to a significant mortality of A. brasilense over time. The ability of A. brasilense to promote wheat growth also decreased due to pesticide treatments combined with sowing delay. Considering that pesticides confer fitness advantages to the wheat in field condition, our results suggest that sowing within the first 4 h after inoculation maintain the beneficial effects of A. brasilense on wheat growth promotion. Furthermore, we conclude that inoculation and treatment of seeds with pesticides may be compatible techniques when carried out immediately before sowing.


Asunto(s)
Azospirillum brasilense , Fungicidas Industriales , Insecticidas , Fungicidas Industriales/farmacología , Insecticidas/farmacología , Raíces de Plantas , Semillas , Triticum
3.
AJNR Am J Neuroradiol ; 39(10): 1867-1870, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-30139755

RESUMEN

3D rotational angiography provides remarkable spatial resolution for cerebrovascular disorders; however, it cannot be integrated directly into gamma knife planning due to the discrepancy of DICOM "tag" information, and most physicians still cannot benefit from 3D rotational angiography. Here, we describe a simple and easy technique to enable the integration of 3D rotational angiography.


Asunto(s)
Angiografía Cerebral/métodos , Imagenología Tridimensional/métodos , Radiocirugia/métodos , Planificación de la Radioterapia Asistida por Computador/métodos , Femenino , Humanos , Masculino
4.
Rev Sci Instrum ; 87(4): 043503, 2016 04.
Artículo en Inglés | MEDLINE | ID: mdl-27131670

RESUMEN

In TST-2 Ohmic discharges, local current is measured using a Rogowski probe by changing the angle between the local magnetic field and the direction of the hole of the Rogowski probe. The angular dependence shows a peak when the direction of the hole is almost parallel to the local magnetic field. The obtained width of the peak was broader than that of the theoretical curve expected from the probe geometry. In order to explain this disagreement, we consider the effect of sheath in the vicinity of the Rogowski probe. A sheath model was constructed and electron orbits were numerically calculated. From the calculation, it was found that the electron orbit is affected by E × B drift due to the sheath electric field. Such orbit causes the broadening of the peak in the angular dependence and the dependence agrees with the experimental results. The dependence of the broadening on various plasma parameters was studied numerically and explained qualitatively by a simplified analytical model.

5.
Med Phys ; 42(9): 5568-77, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26329003

RESUMEN

PURPOSE: Skin toxicity caused by radiotherapy has been visually classified into discrete grades. The present study proposes an objective and continuous assessment method of skin erythema in digital images taken under arbitrary lighting conditions, which is the case for most clinical environments. The purpose of this paper is to show the feasibility of the proposed method. METHODS: Clinical data were gathered from six patients who received carbon beam therapy for lung cancer. Skin condition was recorded using an ordinary compact digital camera under unfixed lighting conditions; a laser Doppler flowmeter was used to measure blood flow in the skin. The photos and measurements were taken at 3 h, 30, and 90 days after irradiation. Images were decomposed into hemoglobin and melanin colors using independent component analysis. Pixel values in hemoglobin color images were compared with skin dose and skin blood flow. The uncertainty of the practical photographic method was also studied in nonclinical experiments. RESULTS: The clinical data showed good linearity between skin dose, skin blood flow, and pixel value in the hemoglobin color images; their correlation coefficients were larger than 0.7. It was deduced from the nonclinical that the uncertainty due to the proposed method with photography was 15%; such an uncertainty was not critical for assessment of skin erythema in practical use. CONCLUSIONS: Feasibility of the proposed method for assessment of skin erythema using digital images was demonstrated. The numerical relationship obtained helped to predict skin erythema by artificial processing of skin images. Although the proposed method using photographs taken under unfixed lighting conditions increased the uncertainty of skin information in the images, it was shown to be powerful for the assessment of skin conditions because of its flexibility and adaptability.


Asunto(s)
Eritema/etiología , Radioterapia de Iones Pesados/efectos adversos , Imagen Molecular , Piel/efectos de la radiación , Anciano , Eritema/metabolismo , Femenino , Humanos , Neoplasias Pulmonares/radioterapia , Masculino , Persona de Mediana Edad , Pigmentación/efectos de la radiación , Piel/metabolismo
7.
Transplant Proc ; 44(8): 2503-4, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23026631

RESUMEN

Endoscopic treatment of biliary tract complications after Roux-en-Y surgery is still a challenge. With balloon enteroscopy, we can reach previously inaccessible areas changing the management of biliopancreatic diseases in patients with surgically altered anatomy. We report a case of single-balloon enteroscopy plus endoscopic retrograde cholangiopancreatography for the treatment of a pinpoint stricture in a hepaticojejunal anastomosis after liver transplantation.


Asunto(s)
Anastomosis en-Y de Roux/efectos adversos , Colangiopancreatografia Retrógrada Endoscópica/métodos , Coledocostomía/efectos adversos , Colestasis Extrahepática/cirugía , Conducto Colédoco/cirugía , Trasplante de Hígado/efectos adversos , Adulto , Colangiopancreatografia Retrógrada Endoscópica/instrumentación , Colestasis Extrahepática/diagnóstico , Colestasis Extrahepática/etiología , Conducto Colédoco/patología , Constricción Patológica , Dilatación , Humanos , Resultado del Tratamiento
8.
Transplant Proc ; 44(8): 2505-6, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23026632

RESUMEN

In pancreas and kidney transplantations, the donor duodenum and pancreas are frequently anastomosed to the jejunum to allow exocrine drainage by creation of a Roux-en-Y jejunal loop. In this situation, those organs are relatively inaccessible using standard endoscopes. We present a case of the use of single-balloon enteroscopy in the treatment of cronic pancreatitis in the donor pancreas.


Asunto(s)
Anastomosis en-Y de Roux/efectos adversos , Colangiopancreatografia Retrógrada Endoscópica , Drenaje/métodos , Trasplante de Riñón/efectos adversos , Trasplante de Páncreas/efectos adversos , Pancreatitis Crónica/cirugía , Esfinterotomía Endoscópica , Anciano , Duodeno/cirugía , Humanos , Yeyuno/cirugía , Masculino , Pancreatitis Crónica/diagnóstico , Pancreatitis Crónica/etiología , Recurrencia , Resultado del Tratamiento
9.
Med Phys ; 39(6Part9): 3699, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28519043

RESUMEN

PURPOSE: To determine a planning target volume (PTV) margin for lung cancer patients using a four-dimensional cone-beam CT (4D CBCT) acquired during volumetric modulated arc therapy (VMAT) treatment. METHODS: A VMAT plan for lung cancer patients was created by Pinnacle v9.0 (Philips) treatment planning system (TPS), where the gross target volume (GTVs) in each breathing phase was delineated by using 4D-planning CT scan (TOSHIBA and ANZAI). The VMAT treatment was performed with a stereotactic body frame after the registration using Elekta X-ray volume imaging (XVI) unit. Simultaneous cone-beam projection images were acquired for 3 or 4 fractions of 10 patients. The in-treatment 4D CBCT was reconstructed by dividing into four breathing phase bins. A total of 38 in-treatment 4D-CBCT sets were exported to Pinnacle TPS. The isocenter of in-treatment 4D CBCT was matched with that of 4D-planning CT. The tumor motion during treatment was manually tracked on in-treatment 4D CBCT, and the center-of-mass (COM) location of the tumor was estimated. Analyzing the tumor regions observed by in-treatment 4D CBCT, a PTV margin in our system was derived. RESULTS: The average difference in COM location of the tumor was less than 1mm for all directions, while the standard deviations (SD's) were about 1.3mm, 1.6mm, and 2.1mm for the lateral, the vertical, and the longitudinal directions, respectively. The large discrepancy more than 3mm was observed for one patient. The required PTV margin was about 3-4mm for the lateral and the vertical directions, whereas it was about 5mm for the longitudinal direction. CONCLUSIONS: The uncertainties of the tumor motion caused by respiration were observed by in-treatment 4D CBCT images. It was feasible to determine the PTV margin from 4D volume images. K. Nakagawa receives research funding from Elekta.

10.
Braz J Med Biol Res ; 39(7): 883-8, 2006 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16862278

RESUMEN

Diabetes mellitus (DM) is a highly prevalent complex genetic disorder. There has been a worldwide effort in the identification of susceptibility genes for DM and its complications, and the 5-10-methylenetetrahydrofolate reductase (MTHFR) and apolipoprotein-E (APOE) genes have been considered good candidate susceptibility genes to this condition. The objectives of the present study were to determine if the 677T MTHFR and epsilon2/epsilon3/epsilon4 APOE alleles are risk factors for DM and for severity of diabetic retinopathy (DR). A total of 248 individuals were studied: 107 healthy individuals and 141 diabetic patients (46 with type 1 diabetes and 95 with type 2 diabetes), who also had DR (81 with non-proliferative DR and 60 with proliferative DR). The polymorphisms were analyzed by PCR followed by digestion with restriction enzyme or the single-nucleotide primer extension method. No evidence of association between the 677TT genotype of MTHFR gene and DM [cases: TT = 10/95 (10.6%); controls: TT = 14/107 (13%)] or with severity of DR was observed [cases: TT = 5/60 (8.5%); controls: TT = 9/81 (11.1%); P > 0.05]. We also did not find evidence of an association between APOE alleles and proliferative DR (epsilon2, epsilon3 and epsilon4 in cases: 9, 76, and 15%, and in controls: 5, 88, and 12%, respectively) but the carriers of epsilon2 allele were more frequent among patients with type 2 DM and DR than in controls [cases: 15/95 (15.8%); controls: 7/107 (6.5%); P < 0.05]. Therefore, our results suggest that the epsilon2 allele/APOE might be a risk factor for diabetes in the Brazilian population.


Asunto(s)
Apolipoproteínas E/genética , Diabetes Mellitus Tipo 1/genética , Diabetes Mellitus Tipo 2/genética , Retinopatía Diabética/genética , Metilenotetrahidrofolato Reductasa (NADPH2)/genética , Anciano , Alelos , Estudios de Casos y Controles , Femenino , Frecuencia de los Genes , Predisposición Genética a la Enfermedad , Genotipo , Humanos , Masculino , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa , Polimorfismo Genético , Factores de Riesgo , Índice de Severidad de la Enfermedad
11.
Braz. j. med. biol. res ; 39(7): 883-888, July 2006. tab
Artículo en Inglés | LILACS | ID: lil-431559

RESUMEN

Diabetes mellitus (DM) is a highly prevalent complex genetic disorder. There has been a worldwide effort in the identification of susceptibility genes for DM and its complications, and the 5-10-methylenetetrahydrofolate reductase (MTHFR) and apolipoprotein-E (APOE) genes have been considered good candidate susceptibility genes to this condition. The objectives of the present study were to determine if the 677T MTHFR and epsilon2/epsilon3/epsilon4 APOE alleles are risk factors for DM and for severity of diabetic retinopathy (DR). A total of 248 individuals were studied: 107 healthy individuals and 141 diabetic patients (46 with type 1 diabetes and 95 with type 2 diabetes), who also had DR (81 with non-proliferative DR and 60 with proliferative DR). The polymorphisms were analyzed by PCR followed by digestion with restriction enzyme or the single-nucleotide primer extension method. No evidence of association between the 677TT genotype of MTHFR gene and DM [cases: TT = 10/95 (10.6 percent); controls: TT = 14/107 (13 percent)] or with severity of DR was observed [cases: TT = 5/60 (8.5 percent); controls: TT = 9/81 (11.1 percent); P > 0.05]. We also did not find evidence of an association between APOE alleles and proliferative DR (epsilon2, epsilon3 and epsilon4 in cases: 9, 76, and 15 percent, and in controls: 5, 88, and 12 percent, respectively) but the carriers of epsilon2 allele were more frequent among patients with type 2 DM and DR than in controls [cases: 15/95 (15.8 percent); controls: 7/107 (6.5 percent); P < 0.05]. Therefore, our results suggest that the epsilon2 allele/APOE might be a risk factor for diabetes in the Brazilian population.


Asunto(s)
Humanos , Persona de Mediana Edad , Apolipoproteínas E/genética , Diabetes Mellitus Tipo 1/genética , /genética , Retinopatía Diabética/genética , /genética , Alelos , Estudios de Casos y Controles , Frecuencia de los Genes , Predisposición Genética a la Enfermedad , Genotipo , Reacción en Cadena de la Polimerasa , Polimorfismo Genético , Factores de Riesgo , Índice de Severidad de la Enfermedad
12.
BJU Int ; 92(7): 803-9, 2003 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-14616470

RESUMEN

OBJECTIVE: To investigate the effects of castration on the expression of endothelins (ETs), ET receptors and ET converting enzyme-1 (ECE-1) in the rat seminal vesicle (RSV). MATERIALS AND METHODS: Sprague-Dawley rats (3 months old) were surgically castrated or sham-operated, and then killed 7 days after surgery. Biochemical and pharmacological properties and the location of ET receptors in the RSV were determined by a series of binding experiments with [125I]ET-1, using membrane particulates and slide-mounted frozen sections of RSV. Expression levels of ETA and ETB receptor subtypes, ET-1, ET-3 and ECE-1 mRNAs were assessed by relative multiplex reverse-transcription polymerase chain reaction (RT-PCR). RESULTS: The density of total ET receptors increased significantly in the seminal vesicle of the castrated rat. The predominance of the ETA receptor subtype in the RSV did not change with castration. Autoradiographic studies showed the presence of ET receptors on the smooth muscle and epithelium of the RSV. In addition, RT-PCR showed an up-regulation in the expression of ETA and ETB receptor subtypes, ET-1 and ECE-1 mRNAs in the seminal vesicle of the castrated rat. However, castration caused no significant change in the expression levels of ET-3 mRNA. CONCLUSION: These findings suggest a regulatory role for testosterone in the expression of the ET receptor system in the RSV.


Asunto(s)
Ácido Aspártico Endopeptidasas/metabolismo , Castración , Endotelinas/metabolismo , Receptores de Endotelina/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Vesículas Seminales/metabolismo , Animales , Autorradiografía/métodos , Enzimas Convertidoras de Endotelina , Masculino , Metaloendopeptidasas , Ratas , Ratas Sprague-Dawley , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/métodos
13.
Pacing Clin Electrophysiol ; 24(10): 1563-5, 2001 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11707052

RESUMEN

Amiodarone is a highly effective antiarrhythmic agent for the prevention of life-threatening arrhythmias. Two cases are described of patients who developed bronchial asthma after treatment with amiodarone. The bronchial asthma resolved after the dose of amiodarone was decreased in both patients. To our knowledge, an association between amiodarone and severe bronchial asthma has previously been reported only once in the medical literature. Physicians should note that amiodarone may cause bronchospasm in susceptible patients.


Asunto(s)
Amiodarona/efectos adversos , Antiarrítmicos/efectos adversos , Asma/inducido químicamente , Anciano , Femenino , Humanos , Masculino
15.
Ann Thorac Cardiovasc Surg ; 7(4): 232-4, 2001 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11578264

RESUMEN

A 13-year-old girl presented with dyspnea and chest pain. Chest radiography showed a massive left pleural effusion. Computed tomography revealed a tumor of the fourth rib. A large bloody effusion was drained. Her anemia worsened (hemoglobin: 4.8 g/dl), and hemorrhagic shock ensued. An emergency thoracotomy was performed. Bleeding from the ruptured tumor was identified. The fourth rib, the tumor, and the adjacent tissues were resected. Histopathologic examination revealed a ruptured primary osteosarcoma of the rib with pleural dissemination.


Asunto(s)
Neoplasias Óseas/complicaciones , Osteosarcoma/complicaciones , Fracturas de las Costillas/complicaciones , Costillas/lesiones , Choque Hemorrágico/etiología , Adolescente , Femenino , Humanos , Rotura/complicaciones
16.
Kyobu Geka ; 54(11): 973-6, 2001 Oct.
Artículo en Japonés | MEDLINE | ID: mdl-11593738

RESUMEN

A 48-years old man complained of dyspnea and was admitted to the hospital. Chest enhanced CT confirmed the presence of the thrombus in the pulmonary artery. Cardiac catheterization showed severe pulmonary hypertension (mean PAP 75 mmHg). ATIII level, protein C and S antigen were within normal range. Anticardiolipin antibody and lupus anti-coagulant determination were negative. He was diagnosed as chronic pulmonary thromboembolism, and underwent pulmonary thromboendarterectomy via median sternotomy under deep hypothermic intermittent circulatory arrest. At the same time IVC filter was inserted. The origin of the thrombus was not detected before operation, but after surgery, MR angiography of total body showed a cavernous hemangioma at left lower limb. We speculated this lesion was the origin of pulmonary embolism.


Asunto(s)
Endarterectomía , Hemangioma Cavernoso/complicaciones , Embolia Pulmonar/cirugía , Enfermedad Crónica , Humanos , Pierna , Masculino , Persona de Mediana Edad , Embolia Pulmonar/etiología
17.
Br J Radiol ; 74(885): 821-4, 2001 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11560830

RESUMEN

The purpose of this study was to evaluate the correlation between fluorine-18 fluorodeoxyglucose (FDG) thymic uptake and a normal appearing thymus on CT. Non-attenuation corrected FDG positron emission tomography (PET) data from 94 young persons (mean age 25.4 years, range 18-29 years) with a normal thymus diagnosed on CT were retrospectively evaluated. No subject had clinical symptoms suggestive of thymus-related disease or mediastinal tumour (follow-up period 6-69 months). PET images were visually assessed and the count ratio between the thymus and the lung (T/L ratio) was calculated. Increased FDG uptake occurred in 32 (34%) subjects. In these 32 cases, the T/L ratio was 2.86+/-0.49 (range 2.02-3.99). In 86 subjects whose CT images were available to calculate the CT attenuation of the thymus (CAT), the CAT value was -17.5+/-45.7 HU (range -103.6 HU to 79.9 HU). The T/L ratio correlated with the CAT value (r=0.58). CAT values in subjects with positive PET findings were significantly higher than CAT values in subjects with negative PET findings (p<0.001, unpaired t-test). These results suggest that even in young adults, if the thymus has a relatively high CT attenuation value, the presence of physiological thymic uptake in FDG-PET is a normal variant. In this study, the diagnosis of normal thymus was based on CT appearance and clinical course. Further studies are needed to clarify the relationship between histopathology and FDG uptake in the thymus.


Asunto(s)
Fluorodesoxiglucosa F18/farmacocinética , Radiofármacos/farmacocinética , Timo/diagnóstico por imagen , Tomografía Computarizada de Emisión , Tomografía Computarizada por Rayos X , Adolescente , Adulto , Humanos , Estudios Retrospectivos , Timo/metabolismo
19.
Pacing Clin Electrophysiol ; 24(8 Pt 1): 1293-4, 2001 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11523620

RESUMEN

Intravenous administration of isoproterenol restored the ST-segment configuration to nearly normal in the right precordial leads and completely prevented spontaneous VF attacks in a patient with Brugada syndrome. The formation of a Brugada-type ECG has been attributed to the transmural dispersion of repolarization of the right ventricular epicardium and related to modulation of the autonomic nervous system. Our case may provide clues to the pathophysiological mechanism of this syndrome.


Asunto(s)
Bloqueo de Rama/complicaciones , Cardiotónicos/uso terapéutico , Isoproterenol/uso terapéutico , Fibrilación Ventricular/prevención & control , Adulto , Muerte Súbita Cardíaca/prevención & control , Electrocardiografía , Humanos , Infusiones Intravenosas , Masculino , Recurrencia , Síndrome , Fibrilación Ventricular/etiología
20.
Jpn J Thorac Cardiovasc Surg ; 49(5): 279-81, 2001 May.
Artículo en Inglés | MEDLINE | ID: mdl-11431945

RESUMEN

OBJECTIVE: Despite the many procedures introduced to prevent surgical site infection during cardiothoracic surgery, serious infections still occur. We attempted to reduce surgical site infection by spraying antibiotic solution in the operative field--a procedure since introduced at 4 other Japanese institutions. METHODS: In the latter half of 1990, we began spraying an antibiotic solution of cefazolin (1g) and gentamicin (40 mg)/40 ml of saline placed in a 50 ml syringe and dispensed through an 18 G needle bent at 60 to 80 degrees to clean the wound during surgery. RESULT: No deep surgical site infections or deaths due to infection have occurred among the 502 patients undergoing cardiothoracic surgery under cardiopulmonary bypass at our hospital. This method was used in over 2,100 cases of similar procedures at 4 other institutions. There were 3 deaths due to severe surgical site infection (0.11%). At one institution treating over 1,000 cases a year, the incidence of death due to surgical site infection decreased significantly after this method was introduced. CONCLUSION: These preliminary experiences show that spraying antibiotic solution in the operative field reduces the risk of surgical site infection in cardiothoracic surgery.


Asunto(s)
Antibacterianos/administración & dosificación , Procedimientos Quirúrgicos Cardíacos/métodos , Infección de la Herida Quirúrgica/prevención & control , Aerosoles , Humanos , Quirófanos
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