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1.
J Craniofac Surg ; 32(6): 2110-2113, 2021 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-33405455

RESUMEN

ABSTRACT: The presenting report describes the use of a posterior cranial vault distraction procedure in resolving a Chiari malformation with associated syringomyelia following a surgically-treated nonsyndromic craniosynostosis. Chiari malformations are typically treated with posterior fossa decompression with or without expansion duraplasty. The objective of this report is to describe the effectiveness in resolving both Chiari malformation and secondary syringomyelia with posterior cranial vault distraction osteogenesis. A 5-year-old male, with a history of surgery for sagittal synostosis during infancy, presented with daily severe headaches and dysesthesias in the hands and feet. Imaging demonstrated a copper-beaten calvarium and a Chiari 1 malformation with a 7 mm diameter C4-T1 syrinx. He underwent posterior cranial vault distraction osteogenesis over 3 months to increase his intracranial volume. The patients' headaches improved significantly, and his dysesthesias resolved postoperatively. A magnetic resonance imaging performed 7 months after completion of distraction demonstrated resolution of the Chiari malformation and decompression of his syrinx. A computed tomography scan at 9 months postdistraction showed resolution of the copper-beaten calvarium. Patients with a history of craniosynostosis can develop inadequate cranial volume over time due to abnormal skull growth, leading to secondary Chiari malformation with or without syringomyelia. Posterior vault distraction is an effective strategy to address these conditions and can be employed later in childhood to treat the underlying pathology. The mechanism potentially expands both calvarium and dura, which in turn addresses both the Chiari malformation and secondary syringomyelia.


Asunto(s)
Malformación de Arnold-Chiari , Craneosinostosis , Osteogénesis por Distracción , Siringomielia , Malformación de Arnold-Chiari/complicaciones , Malformación de Arnold-Chiari/cirugía , Preescolar , Craneosinostosis/complicaciones , Craneosinostosis/diagnóstico por imagen , Craneosinostosis/cirugía , Descompresión Quirúrgica , Humanos , Imagen por Resonancia Magnética , Masculino , Cráneo/cirugía , Siringomielia/cirugía , Resultado del Tratamiento
2.
Aesthet Surg J ; 41(5): 627-634, 2021 04 12.
Artículo en Inglés | MEDLINE | ID: mdl-32291444

RESUMEN

BACKGROUND: Cosmetic surgery tourism is increasing exponentially. Patients seek cosmetic procedures within the United States and abroad, lured by lower cost procedures, shorter waiting lists, and affordable airfare and hotel accommodations. Unfortunately, operations are often performed by non-board-certified plastic surgeons, sometimes not even by plastic surgeons. Preoperative counseling, frequently limited to a video-chat with an office secretary, provides inadequate discussion regarding potential complications. Postoperative care is careless and rarely involves the operating surgeon. Complications are frequent, with management falling into the hands of plastic surgeons unfamiliar with the patient's care. Furthermore, the physician, rather than the patient or hospital, faces the largest cost burden. OBJECTIVES: The authors sought to explore their institution's experience treating complications of cosmetic tourism and investigate associated costs. METHODS: The retrospective review of 16 patients treated for complications related to cosmetic surgery tourism plus cost analysis revealed a substantial discrepancy between money saved by undergoing surgery abroad and massive costs accrued to treat surgical complications. RESULTS: The most common complication was infection, often requiring surgery or IV antibiotics on discharge. Mean cost per patient was $26,657.19, ranging from $392 (single outpatient visit) to $154,700.79 (prolonged admission and surgery). Overall, the hospital retained 63% of billed charges, while physicians retained only 9%. The greatest amount paid by any single patient was $2635.00 by a patient with private insurance. CONCLUSIONS: Cosmetic tourism has severe medical repercussions for patients and complications that burden hospitals, physicians, and the US medical system. Physicians treating the complications suffer the greatest financial loss.


Asunto(s)
Turismo Médico , Cirugía Plástica , Costos y Análisis de Costo , Humanos , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/terapia , Estudios Retrospectivos , Cirugía Plástica/efectos adversos , Turismo
3.
Age Ageing ; 49(5): 814-820, 2020 08 24.
Artículo en Inglés | MEDLINE | ID: mdl-32147721

RESUMEN

BACKGROUND: Data on drug utilisation patterns in nursing home populations is scarce. We aimed to describe drug use patterns in Danish nursing home residents. METHODS: We established a cohort of 5,179 individuals (63% women; median age of 84 years) admitted into 94 nursing homes across Denmark during 2015-2017. Data on prescription drug use and other census data were obtained from the nationwide Danish health registries. RESULTS: The total number of drug classes filled increased from a median of 6 drugs (interquartile range [IQR] 3-9) at 18-24 months before nursing home admission to a median of 8 drugs (IQR 6-11) just after admission, with the most common drug classes comprising paracetamol (61%), platelet inhibitors (41%), proton pump inhibitors (34%), statins (33%) and potassium supplements (31%). The incidence rate of new drug treatments increased from 21 new treatments/100 residents/month at 12-24 months before admission to a peak of 71 new treatments/100 residents/month in the month prior to admission, while it levelled off to about 34 new treatments/100 residents/month after 6-9 months. The drug classes primarily responsible for this peak were laxatives, antibiotics and analgesics. The largest absolute increases were seen for laxatives (53%), paracetamol (43%) and antidepressants (36%), all showing a marked increase up to and following admission. A high proportion of residents remained on therapy in the 3-year period following admission, with users of antidepressants and antidementia drugs being most persistent. CONCLUSION: Nursing home admission is associated with an increase in use of both predominantly preventive and non-preventive drug classes.


Asunto(s)
Utilización de Medicamentos , Casas de Salud , Antidepresivos , Estudios de Cohortes , Dinamarca/epidemiología , Femenino , Humanos , Masculino
4.
Biomacromolecules ; 20(1): 443-453, 2019 01 14.
Artículo en Inglés | MEDLINE | ID: mdl-30525515

RESUMEN

Cellulose fibers can be freed from the cell-wall skeleton via high-shear homogenization, to produce cellulose nanofibers (CNF) that can be used, for example, as the reinforcing phase in composite materials. Nanofiber production from agro-industrial byproducts normally involves harsh chemical-pretreatments and high temperatures to remove noncellulosic polysaccharides (20-70% of dry weight). However, this is expensive for large-scale processing and environmentally damaging. An enzyme-only pretreatment to obtain CNF from agro-industrial byproducts (potato and sugar beet) was developed with targeted commercial enzyme mixtures. It is hypothesized that cellulose can be isolated from the biomass, using enzymes only, due to the low lignin content, facilitating greater liberation of CNF via high-shear homogenization. Comprehensive Microarray Polymer Profiling (CoMPP) measured remaining extractable polysaccharides, showing that the enzyme-pretreatment was more successful at removing noncellulosic polysaccharides than alkaline- or acid-hydrolysis alone. While effective alone, the effect of the enzyme-pretreatment was bolstered via combination with a mild high-pH pretreatment. Dynamic rheology was used to estimate the proportion of CNF in resultant suspensions. Enzyme-pretreated suspensions showed 4-fold and 10-fold increases in the storage modulus for potato and sugar beet, respectively, compared to untreated samples. A greener yet facile method for producing CNF from vegetable waste is presented here.


Asunto(s)
Biotecnología/métodos , Celulosa/análogos & derivados , Residuos Industriales , Nanofibras/química , Verduras/química , Beta vulgaris/química , Biocatálisis , Hidrólisis , Solanum tuberosum/química
5.
Age Ageing ; 49(1): 67-73, 2019 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-31763682

RESUMEN

BACKGROUND: the increasing number of multimorbid older people places high demands on future health care systems. To inform the discussion on how to structure future care strategies, we aimed to describe the temporal relationship between admission, and morbidity and mortality in nursing home residents. METHODS: data on 5,179 older individuals admitted to 94 Danish nursing homes in 12 municipalities during 2015-2017 were linked to the nationwide Danish health registries to retrieve information on the temporal relation between nursing home admission and morbidity and mortality. RESULTS: at the time of nursing home admission, the majority were women (63%). Male residents were younger than women (median 82 vs 85 years) and had a higher prevalence of comorbidities (median Charlson score 2 vs 1 among women). The median survival after nursing home admission was 25.8 months, with the 3-year survival being 37%. Three-year survival was lower among men (29 vs 43% among women) and among the oldest residents (23% among those aged ≥90 years vs 64% among individuals ≤65 years). In addition to age and sex, predictors of mortality included hospitalisations prior to nursing home admission and a high burden of comorbidity. The rate of hospitalisations, primarily for reasons related to frailty, increased substantially during the 9 months prior to nursing home admission. CONCLUSION: we provide detailed information on differences in morbidity and mortality across age span and sex at the time of nursing home admission, thereby contributing to the ongoing discussion of how to structure the future health care system.


Asunto(s)
Morbilidad , Mortalidad , Casas de Salud/estadística & datos numéricos , Factores de Edad , Anciano , Anciano de 80 o más Años , Dinamarca/epidemiología , Femenino , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Sistema de Registros , Factores Sexuales , Análisis de Supervivencia , Factores de Tiempo
6.
Langmuir ; 33(39): 10143-10152, 2017 10 03.
Artículo en Inglés | MEDLINE | ID: mdl-28876958

RESUMEN

This work examines the anisotropic electroless plating of DNA-functionalized gold nanorods attached to a DNA origami template to fabricate continuous metal structures of rectanglar, square, and T shapes. DNA origami, a versatile method for assembling a variety of 2- and 3-D nanostructures, is utilized to construct the DNA breadboard template used for this study. Staple strands on selective sites of the breadboard template are extended with an additional nucleotide sequence for the attachment of DNA-functionalized gold nanorods to the template via base pairing. The nanorod-seeded DNA templates are then introduced into an electroless gold plating solution to determine the extent to which the anisotropic growth of the nanorods is able to fill the gaps between seeds to create continuous structures. Our results show that the DNA-functionalized nanorods grow anisotropically during plating at a rate that is approximately 4 times faster in the length direction than in the width direction to effectively fill gaps of up to 11-13 nm in length. The feasibility of using this directional growth at specific sites to enable the fabrication of continuous metal nanostructures with diameters as thin as 10 nm is demonstrated and represents important progress toward the creation of devices and systems based on self-assembled biological templates.


Asunto(s)
Nanotubos , Anisotropía , ADN , Oro , Nanoestructuras
7.
Langmuir ; 33(3): 726-735, 2017 01 24.
Artículo en Inglés | MEDLINE | ID: mdl-28075137

RESUMEN

An improved method for the metallization of DNA origami is examined in this work. DNA origami, a simple and robust method for creating a wide variety of nanostructured shapes and patterns, provides an enabling template for bottom-up fabrication of next-generation nanodevices. Selective metallization of these DNA templates is needed to make nanoelectronic devices. Here, we demonstrate a metallization process that uses gold nanorod seeds followed by anisotropic plating to provide improved morphology and greater control of the final metallized width of the structure. In our approach, gold nanorods are attached to an origami template to create a seed layer. Electroless gold deposition is then used to fill the gaps between seeds in order to create continuous, conductive nanowires. Importantly, growth during electroless deposition occurs preferentially in the length direction at a rate that is approximately 4 times the growth rate in the width direction, which enables fabrication of narrow, continuous wires. The electrical properties of 49 nanowires with widths ranging from 13 to 29 nm were characterized, and resistivity values as low as 8.9 × 10-7 Ω·m were measured. The anisotropic metallization process presented here represents important progress toward the creation of nanoelectronic devices by molecularly directed placement of functional components onto self-assembled biological templates.


Asunto(s)
ADN/química , Nanocables/química , Anisotropía , Conductividad Eléctrica , Galvanoplastia , Oro/química , Nanopartículas del Metal/química , Nanotubos/química , Conformación de Ácido Nucleico , Tamaño de la Partícula
8.
Pediatr Dermatol ; 34(3): 331-336, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28523875

RESUMEN

Infantile hemangiomas (IHs) are the most common tumors of infancy and usually follow a typical course of growth and involution. We report four soft tissue tumors that were referred to the pediatric dermatology clinic as IHs and the process by which they were diagnosed and treated. Clinicians should be aware of presentations of these uncommon, but serious soft tissue tumors. Many of these mimickers have a vastly different clinical prognosis, and early intervention to limit sequelae is crucial. Biopsy of atypical lesions should be considered early in the diagnostic process since they have varied prognosis and treatment strategies.


Asunto(s)
Hemangioma/diagnóstico , Neoplasias de los Tejidos Blandos/diagnóstico , Biopsia , Preescolar , Diagnóstico Diferencial , Humanos , Lactante , Recién Nacido , Masculino , Pronóstico , Neoplasias de los Tejidos Blandos/tratamiento farmacológico , Neoplasias de los Tejidos Blandos/cirugía
9.
Ecotoxicol Environ Saf ; 135: 267-275, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27750094

RESUMEN

Contaminated soil is a problem throughout the industrialized world, and a significant proportion of these sites are polluted with heavy metals such as copper. Ecological risk assessment of contaminated sites requires ecotoxicological studies with spiked soils as well as in-situ ecological observations. Here, we report laboratory and field assessment of copper toxicity for earthworms at a Danish site (Hygum) exclusively contaminated with an increasing gradient in copper from background to highly toxic levels (>1000mgkg-1 dry soil). More specifically, we report effects on field populations, body contents of copper, hatching of earthworm cocoons and reproduction of the common species Aporrectodea tuberculata. Abundance of earthworms and cocoons decreased significantly from about 400-150m-2 along the gradient as the soil copper concentration increased from ca. 50 to ca. 1000mgkg-1. At lower concentrations, the population was dominated by endogeic species, whereas at high concentrations the population was dominated by epigeic species. At high copper contents the internal concentration of copper was in the range 100-160mgkg-1 dry tissue. Despite the high internal copper contents, hatchability of field collected cocoons was not impaired in any species. The EC50 reproduction value of A. tuberculata was about 220mg copper kg-1 dry soil in the first two exposure periods, but nearly doubled in the third period suggesting that an acclimation response had occurred. Also in the laboratory reproduction test, cocoon hatchability was not reduced, but rather slightly stimulated by copper. Based on these results we discuss the possibility that acute exposure in laboratory experiments is more detrimental than exposure in a field situation, perhaps because increased tolerance may be acquired through natural selection and genetic adaptation through increased use of defense mechanisms such as metallothioneins. Further, we discuss that the rather high tissue copper level of earthworms from the Hygum site may have smaller effects in these free-ranging worms than it would have in acute-exposure laboratory tests because the copper is more efficiently sequestered and detoxified in the field situation where populations have been exposed for many generations.


Asunto(s)
Cobre/toxicidad , Oligoquetos/efectos de los fármacos , Reproducción/efectos de los fármacos , Contaminantes del Suelo/toxicidad , Aclimatación/efectos de los fármacos , Adaptación Fisiológica/genética , Animales , Biomasa , Cobre/análisis , Ecología , Metalotioneína/metabolismo , Metamorfosis Biológica/efectos de los fármacos , Oligoquetos/química , Selección Genética
10.
Altern Complement Ther ; 23(6): 236-243, 2017 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-29225455

RESUMEN

Objectives: The aims of this study were to assess the effects of an intervention of Iyengar yoga and coherent breathing at five breaths per minute on depressive symptoms and to determine optimal intervention yoga dosing for future studies in individuals with major depressive disorder (MDD). Methods: Subjects were randomized to the high-dose group (HDG) or low-dose group (LDG) for a 12-week intervention of three or two intervention classes per week, respectively. Eligible subjects were 18-64 years old with MDD, had baseline Beck Depression Inventory-II (BDI-II) scores ≥14, and were either on no antidepressant medications or on a stable dose of antidepressants for ≥3 months. The intervention included 90-min classes plus homework. Outcome measures were BDI-II scores and intervention compliance. Results: Fifteen HDG (Mage=38.4±15.1 years) and 15 LDG (Mage=34.7±10.4 years) subjects completed the intervention. BDI-II scores at screening and compliance did not differ between groups (p=0.26). BDI-II scores declined significantly from screening (24.6±1.7) to week 12 (6.0±3.8) for the HDG (-18.6±6.6; p < 0.001), and from screening (27.7±2.1) to week 12 (10.1±7.9) in the LDG (-17.7±9.3; p < 0.001). There were no significant differences between groups, based on response (i.e., >50% decrease in BDI-II scores; p=0.65) for the HDG (13/15 subjects) and LDG (11/15 subjects) or remission (i.e., number of subjects with BDI-II scores <14; p=1.00) for the HDG (14/15 subjects) and LDG (13/15 subjects) after the 12-week intervention, although a greater number of subjects in the HDG had 12-week BDI-II scores ≤10 (p=0.04). Conclusion: During this 12-week intervention of yoga plus coherent breathing, depressive symptoms declined significantly in patients with MDD in both the HDG and LDG. Both groups showed comparable compliance and clinical improvements, with more subjects in the HDG exhibiting BDI-II scores ≤10 at week 12.

11.
Dis Aquat Organ ; 118(2): 113-27, 2016 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-26912042

RESUMEN

Long-term monitoring of amphibians is needed to clarify population-level effects of ranaviruses (Rv) and the fungal pathogen Batrachochytrium dendrobatidis (Bd). We investigated disease dynamics of co-occurring amphibian species and potential demographic consequences of Rv and Bd infections at a montane site in the Southern Appalachians, Georgia, USA. Our 3-yr study was unique in combining disease surveillance with intensive population monitoring at a site where both pathogens are present. We detected sub-clinical Bd infections in larval and adult red-spotted newts Notophthalmus viridescens viridescens, but found no effect of Bd on body condition of adult newts. Bd infections also occurred in larvae of 5 anuran species that bred in our fishless study pond, and we detected co-infections with Bd and Rv in adult newts and larval green frogs Lithobates clamitans. However, all mortality and clinical signs in adult newts and larval anurans were most consistent with ranaviral disease, including a die-off of larval wood frogs Lithobates sylvaticus in small fish ponds located near our main study pond. During 2 yr of drift fence monitoring, we documented high juvenile production in newts, green frogs and American bullfrogs L. catesbeianus, but saw no evidence of juvenile recruitment in wood frogs. Larvae of this susceptible species may have suffered high mortality in the presence of both Rv and predators. Our findings were generally consistent with results of Rv-exposure experiments and support the purported role of red-spotted newts, green frogs, and American bullfrogs as common reservoirs for Bd and/or Rv in permanent and semi-permanent wetlands.


Asunto(s)
Notophthalmus/microbiología , Notophthalmus/virología , Estanques , Conducta Predatoria , Rana clamitans/microbiología , Rana clamitans/virología , Animales , Quitridiomicetos/inmunología , Infecciones por Virus ADN/epidemiología , Infecciones por Virus ADN/veterinaria , Infecciones por Virus ADN/virología , Georgia , Larva/microbiología , Larva/virología , Micosis/microbiología , Micosis/transmisión , Micosis/veterinaria , Rana clamitans/fisiología , Ranavirus/aislamiento & purificación , Estaciones del Año , Factores de Tiempo
12.
Cleft Palate Craniofac J ; 53(1): 64-72, 2016 01.
Artículo en Inglés | MEDLINE | ID: mdl-25489772

RESUMEN

OBJECTIVE: The aims of this retrospective study were to evaluate the volumetric outcome of mandibular symphyseal bone graft in patients with unilateral cleft lip and palate by estimating the bone fill 1-year postoperatively on cone beam computed tomography. The outcome was assessed in relation to the (1) root development stage of the cleft side canine, (2) presence/absence of a cleft side lateral incisor, and (3) volume size of the preoperative cleft defect. METHODS: The alveolar bone defect volume of 32 consecutive unilateral cleft lip and palate patients aged 8 years 1 month to 11 years 11 months was evaluated using a recently defined and standardized protocol. The outcome was calculated as the percentage of bone fill using the formula (VOLpre - VOLpost) / VOLpre) × 100. RESULTS: The preoperative mean alveolar cleft volume was 934 mm(3), and the average percentage bone fill was 87%. There was no significant difference between bone fill and root developmental stage of the cleft-side canine (P = .882) nor presence/absence of the cleft side lateral incisor (P = .803). The size of the cleft defect did not correlate with the bone fill (r = .03, P = .84). CONCLUSIONS: Secondary alveolar bone grafting with mandibular symphyseal bone graft in patients with unilateral cleft lip and palate is an attractive procedure assessed from the volumetric outcome using cone beam computed tomography. The 1-year average bone fill of 87% was not significantly influenced by root development stage of the cleft-side canine, presence or the absence of a cleft side lateral incisor, or size of the alveolar defect.


Asunto(s)
Injerto de Hueso Alveolar/métodos , Labio Leporino/cirugía , Fisura del Paladar/cirugía , Tomografía Computarizada de Haz Cónico/métodos , Mandíbula/trasplante , Niño , Dinamarca , Femenino , Humanos , Masculino , Estudios Retrospectivos , Resultado del Tratamiento
13.
Cleft Palate Craniofac J ; 52(3): e47-55, 2015 05.
Artículo en Inglés | MEDLINE | ID: mdl-25706336

RESUMEN

OBJECTIVE: The aims of this study were (1) to determine the three-dimensional anatomical boundaries of the alveolar bone defect in cleft lip and palate (CLP) patients, (2) to precisely translate these anatomical boundaries into reliable cephalometric landmarks and planes that can be used for cone beam computed tomography (CBCT) analysis, (3) to standardize image acquisition and reconstruction parameters, and (4) to test the reproducibility of the proposed protocol for measuring the predefined alveolar bone defect, using a third-party software. METHODS: The alveolar bone defect volume of 10 randomly selected patients with unilateral CLP (UCLP) aged 8 years and 6 months to 11 years and 2 months was evaluated on preoperative and 1-year postoperative CBCT scans using a semiautomatic, standardized protocol. The alveolar bone graft outcome was calculated as a percentage of the bone fill using the formula (VOLpre - VOLpost)/VOLpre) × 100. Intra- and interobserver reliability was assessed. RESULTS: Intra- and interobserver reproducibility was excellent for volumes and bone fill as no statistically significant difference (P < .001) was seen between the different sets of measurements, and Pearson correlation coefficients were large (intraobserver: r > .9849, interobserver: r > .8784). The Bland-Altman plots indicated that the differences between the plots were not patterned. CONCLUSIONS: Volume determination using CBCT, third-party medical image processing software, and the presently defined image acquisition and reconstruction parameters, including anatomical boundaries, is a reproducible and practical method for assessing the volumetric outcome of secondary alveolar bone grafting in patients with UCLP.


Asunto(s)
Injerto de Hueso Alveolar , Proceso Alveolar/anomalías , Proceso Alveolar/diagnóstico por imagen , Proceso Alveolar/cirugía , Tomografía Computarizada de Haz Cónico , Puntos Anatómicos de Referencia , Niño , Labio Leporino/diagnóstico por imagen , Labio Leporino/cirugía , Fisura del Paladar/diagnóstico por imagen , Fisura del Paladar/cirugía , Femenino , Humanos , Imagenología Tridimensional , Masculino , Interpretación de Imagen Radiográfica Asistida por Computador , Reproducibilidad de los Resultados , Programas Informáticos , Resultado del Tratamiento
14.
World J Microbiol Biotechnol ; 30(3): 1129-34, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24142427

RESUMEN

Competitiveness for nodulation is a desirable trait in rhizobia strains used as inoculant. In Sinorhizobium meliloti 1021 mutation in either of the trehalose utilization genes thuA or thuB influences its competitiveness for root colonization and nodule occupancy depending on the interacting host. We have therefore investigated whether mutation in the thuA ortholog in Mesorhizobium loti MAFF303099 also leads to a similar competitive phenotype on its hosts. The results show that M. loti thuA mutant Ml7023 was symbiotically effective and was as competitive as the wild type in colonization and nodule occupancy on Lotus corniculatus and Lotus japonicus. The thuA gene in M. loti was not induced during root colonization or in the infection threads unlike in S. meliloti, despite its induction by trehalose and high osmolarity in in vitro assays.


Asunto(s)
Proteínas Bacterianas/metabolismo , Lotus/microbiología , Mesorhizobium/enzimología , Mesorhizobium/crecimiento & desarrollo , Nodulación de la Raíz de la Planta , Trehalosa/metabolismo , Proteínas Bacterianas/genética , Mesorhizobium/metabolismo , Mesorhizobium/fisiología , Mutación , Raíces de Plantas/microbiología , Simbiosis
15.
J Bacteriol ; 195(17): 3797-807, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23772075

RESUMEN

The thu operon (thuEFGKAB) in Sinorhizobium meliloti codes for transport and utilization functions of the disaccharide trehalose. Sequenced genomes of members of the Rhizobiaceae reveal that some rhizobia and Agrobacterium possess the entire thu operon in similar organizations and that Mesorhizobium loti MAFF303099 lacks the transport (thuEFGK) genes. In this study, we show that this operon is dedicated to the transport and assimilation of maltitol and isomers of sucrose (leucrose, palatinose, and trehalulose) in addition to trehalulose, not only in S. meliloti but also in Agrobacterium tumefaciens. By using genetic complementation, we show that the thuAB genes of S. meliloti, M. loti, and A. tumefaciens are functionally equivalent. Further, we provide both genetic and biochemical evidence to show that these bacteria assimilate these disaccharides by converting them to their respective 3-keto derivatives and that the thuAB genes code for this ketodisaccharide-forming enzyme(s). Formation of 3-ketotrehalose in real time in live S. meliloti is shown through Raman spectroscopy. The presence of an additional ketodisaccharide-forming pathway(s) in A. tumefaciens is also indicated. To our knowledge, this is the first report to identify the genes that code for the conversion of disaccharides to their 3-ketodisaccharide derivatives in any organism.


Asunto(s)
Agrobacterium tumefaciens/metabolismo , Maltosa/análogos & derivados , Operón , Sinorhizobium meliloti/metabolismo , Sacarosa/metabolismo , Alcoholes del Azúcar/metabolismo , Trehalosa/metabolismo , Agrobacterium tumefaciens/química , Agrobacterium tumefaciens/genética , Transporte Biológico , Biotransformación , Prueba de Complementación Genética , Maltosa/metabolismo , Redes y Vías Metabólicas/genética , Sinorhizobium meliloti/química , Sinorhizobium meliloti/genética , Espectrometría Raman
16.
Anal Chem ; 85(15): 7264-70, 2013 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-23796054

RESUMEN

Having the ability to monitor metabolic activity at the scale of single bacterial cells noninvasively would enable us to follow changes in the distribution of activity in bacterial systems which is of major importance for topics such as integration of metabolism and development, metabolic engineering, microbial activity and drug resistance, cell-cell interactions, and quorum sensing. Here, we used laser tweezers Raman spectroscopy to monitor the in vivo real-time uptake and conversion of trehalose by single bacterial cells. This approach can be used for the quantitative determination of sugar uptake by a single bacterium and its metabolic response to the sugar application with time. We show that uptake of trehalose can be quantified in single living bacterial cells held in place by an optical trap while simultaneously collecting Raman spectra upon application of sugar to the medium. This technique yields real-time chemical information in a label-free manner, thus eliminating the limitations of toxicity of the isotopic probes common in studying transport processes. It can substitute the laborious and time-consuming analytical evaluation. Although the single-cell Raman spectroscopy method demonstrated here is focused on the study of trehalose uptake by Sinorhizobium meliloti, the demonstrated approach is applicable to many different organisms and carbohydrates in general.


Asunto(s)
Pinzas Ópticas , Sinorhizobium meliloti/metabolismo , Espectrometría Raman , Trehalosa/metabolismo , Transporte Biológico , Supervivencia Celular , Análisis de la Célula Individual , Sinorhizobium meliloti/citología , Microbiología del Suelo
17.
J Clin Psychopharmacol ; 33(5): 627-35, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23948785

RESUMEN

BACKGROUND: Bipolar disorder may be associated with mitochondrial dysfunction. Therefore, agents that enhance mitochondrial functioning may be efficacious in bipolar disorder. We performed a randomized placebo-controlled trial of the mitochondrial enhancers acetyl-L-carnitine (ALCAR) and α-lipoic acid (ALA) in patients with bipolar depression, and assessed markers of cerebral energy metabolism using phosphorus magnetic resonance spectroscopy. METHODS: We administered ALCAR (1000-3000 mg daily) plus ALA (600-1800 mg daily) or placebo for 12 weeks to 40 patients with bipolar depression and obtained imaging data at baseline, week 1, and week 12 of treatment in 20 patients using phosphorus 3-dimensional chemical-shift imaging at 4 T. Statistical analysis used random effects mixed models. RESULTS: We found no significant difference between ALCAR/ALA and placebo on change from baseline in the Montgomery-Asberg Depression Rating Scale in both the longitudinal (mean difference [95% confidence interval], -1.4 [-6.2 to 3.4], P = 0.58) and last-observation-carried-forward (-3.2 [-7.2 to 0.9], P = 0.12) analyses. ALCAR/ALA treatment significantly reduced phosphocreatine levels in the parieto-occipital cortex at week 12 (P = 0.002). Reduction in whole brain total nucleoside triphosphate levels from baseline to week 1 was associated with reduction in Montgomery-Asberg Depression Rating Scale scores (P = 0.02) in patients treated with ALCAR/ALA. However, this was likely a chance finding attributable to multiple statistical comparisons. CONCLUSIONS: Treatment with ALCAR and ALA at the dose and duration used in this study does not have antidepressant effects in depressed bipolar patients and does not significantly enhance mitochondrial functioning in this patient group.


Asunto(s)
Acetilcarnitina/uso terapéutico , Antidepresivos/uso terapéutico , Trastorno Bipolar/tratamiento farmacológico , Ácido Tióctico/uso terapéutico , Adulto , Trastorno Bipolar/diagnóstico , Trastorno Bipolar/metabolismo , Trastorno Bipolar/psicología , Encéfalo/efectos de los fármacos , Encéfalo/metabolismo , Distribución de Chi-Cuadrado , Quimioterapia Combinada , Metabolismo Energético/efectos de los fármacos , Femenino , Humanos , Modelos Lineales , Espectroscopía de Resonancia Magnética , Masculino , Persona de Mediana Edad , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Fosfocreatina/metabolismo , Escalas de Valoración Psiquiátrica , Factores de Tiempo , Resultado del Tratamiento
18.
Environ Sci Technol ; 47(15): 8674-83, 2013 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-23802136

RESUMEN

The aim of the present study was to evaluate the secondary ecotoxicological effects of soil amendment materials that can be added to contaminated soils in order to sequester harmful pollutants. To this end, a nonpolluted agricultural soil was amended with 0.5, 2, and 5% of the following four amendments: powder activated carbon (PAC), granular activated carbon, corn stover biochar, and ferric oxyhydroxide powder, which have previously been proven to sequester pollutants in soil. The resulting immediate effects (i.e., without aging the mixtures before carrying out tests) on the springtail Folsomia candida, the earthworm species Aporectodea caliginosa and Eisenia fetida, the marine bacteria Vibrio fischeri, a suite of ten prokaryotic species, and a eukaryote (the yeast species Pichia anomalia) were investigated. Reproduction of F. candida was significantly increased compared to the unamended soil when 2% biochar was added to it. None of the treatments caused a negative effect on reproduction. All amendments had a deleterious effect on the growth of A. caliginosa when compared to the unamended soil, except the 0.5% amendment of biochar. In avoidance tests, E. fetida preferred biochar compared to all other amendments including the unamended soil. All amendments reduced the inhibition of luminescence to V. fischeri, i.e., were beneficial for the bacteria, with PAC showing the greatest improvement. The effects of the amendments on the suite of prokaryotic species and the eukaryote were variable, but overall the 2% biochar dose provided the most frequent positive effect on growth. It is concluded that the four soil amendments had variable but never strongly deleterious effects on the bacteria and invertebrates studied here during the respective recommended experimental test periods.


Asunto(s)
Bacterias/efectos de los fármacos , Carbono/farmacología , Carbón Orgánico , Compuestos Férricos/farmacología , Invertebrados/efectos de los fármacos , Microbiología del Suelo , Suelo/química , Animales , Invertebrados/fisiología
19.
Psychiatry Res ; 191(3): 201-11, 2011 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-21334181

RESUMEN

Chronic marijuana (MRJ) use is associated with altered cognition and mood state, altered brain metabolites, and functional and structural brain changes. The objective of this study was to apply proton magnetic resonance spectroscopic imaging (MRSI) to compare proton metabolite levels in 15 young men with MRJ dependence and 11 healthy non-using (NU) young men. Spectra were acquired at 4.0 Tesla using 2D J-resolved MRSI to resolve coupled resonances in J-space and to quantify the entire J-coupled spectral surface of metabolites from voxels containing basal ganglia and thalamus, temporal and parietal lobes, and occipital white and gray matter. This method permitted investigation of high-quality spectra for regression analyses to examine metabolites relative to tissue type. Distribution of myo-inositol (mI)/creatine (Cr) was altered in the MRJ group whereas the NU group exhibited higher mI/Cr in WM than GM, this pattern was not observed in MRJ subjects. Significant relationships observed between global mI/Cr and distribution in WM, and self-reported impulsivity and mood symptoms were also unique between MRJ and NU groups. These preliminary findings suggest that mI, and distribution of this glial metabolite in WM, is altered by MRJ use and is associated with behavioral and affective features reported by young MRJ-dependent men.


Asunto(s)
Encéfalo/metabolismo , Encéfalo/patología , Fumar Marihuana/patología , Fibras Nerviosas Mielínicas/metabolismo , Adolescente , Adulto , Análisis de Varianza , Ácido Aspártico/análogos & derivados , Ácido Aspártico/metabolismo , Mapeo Encefálico , Colina/metabolismo , Creatina/metabolismo , Humanos , Espectroscopía de Resonancia Magnética , Masculino , Escalas de Valoración Psiquiátrica , Estadística como Asunto , Adulto Joven
20.
J Oral Maxillofac Surg ; 69(1): 104-13, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21050649

RESUMEN

PURPOSE: A prospective, controlled study of consecutive surgical-orthodontic patients was performed to assess how treatment affects the patients' psychosocial well-being. We evaluated patients' treatment motivations and motive fulfillment in relation to their satisfaction with the treatment and assessed the correlation between their satisfaction and their psychosocial well-being. PATIENTS AND METHODS: A total of 118 adult patients (51 men and 67 women, mean age 25 years) who had undergone surgical-orthodontic treatment were examined before the preoperative orthodontic treatment and 12 months after surgery or later. The motives for treatment, fulfillment of those motives, psychosocial well-being, and degree of post-treatment satisfaction were assessed using questionnaires validated for Danish patients. A total of 47 age- and gender-matched subjects without any current or previous need for orthodontic or surgical-orthodontic treatment served as the controls. RESULTS: The patients stated oral function and appearance as their main treatment motives, and most reported that their motives had been fulfilled. Both their motives and the actual fulfillment of their motives influenced their treatment satisfaction. Another significant outcome of treatment was improved self-concept and social interaction. The more self-concept and social interaction were improved by treatment, the greater the post-treatment satisfaction the patients expressed. CONCLUSIONS: Surgical-orthodontic treatment has significant potential to improve patients' psychosocial well-being. Patients' satisfaction with treatment correlated with the post-treatment psychosocial status. However, pretreatment motives significantly influenced the overall satisfaction after treatment. Thus, patients who weighted oral function motives greatest expressed the lowest degree of treatment satisfaction.


Asunto(s)
Salud Mental , Motivación , Ortodoncia Correctiva/psicología , Procedimientos Quirúrgicos Ortognáticos/psicología , Satisfacción del Paciente , Adulto , Actitud Frente a la Salud , Estudios de Casos y Controles , Oclusión Dental , Estética Dental , Femenino , Estudios de Seguimiento , Estado de Salud , Humanos , Relaciones Interpersonales , Masculino , Masticación/fisiología , Enfermedades Periodontales/prevención & control , Estudios Prospectivos , Autoimagen , Factores Sexuales , Habla/fisiología , Trastornos de la Articulación Temporomandibular/prevención & control , Pérdida de Diente/prevención & control
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