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1.
J Arthroplasty ; 38(3): 476-483, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36252742

RESUMEN

BACKGROUND: Consensus regarding prior dental problems on the outcomes of total knee arthroplasty (TKA) patients is lacking. Therefore, our objectives were to determine the association of dental caries or dental implant placement in TKA patients on the following: (1) medical complications; (2) health care utilization (lengths of stay and readmissions); (3) implant-related complications; and (4) expenditures. METHODS: A retrospective query was performed using an administrative claims database for 3 patient cohorts undergoing primary TKA from 2010 to 2020. Patients who had a history of dental caries or implant placement 1 year prior to TKA (n = 1,466) and 1 year after TKA (n = 1,127) were case-matched to patients who did not have a dental history by age and comorbidities. Outcomes included 90-day complications, health care utilization parameters, 2-year implant complications, and expenditures. Logistic regression models computed odds ratios (OR) of complications and readmissions. P values less than 0.005 were significant. RESULTS: Patients who had a dental implant placement prior to TKA had higher frequency of complications (20.05 versus 14.01%; OR: 1.53, P < .0001), including myocardial infarctions (2.52 versus 1.23%; OR: 2.08, P = .0002) and pneumonia (2.52 versus 1.24%; OR: 2.06, P = .0002). Lengths of stay (3.28 versus 2.98 days; P = .255), readmission rates (4.71 versus 4.28%; P = .470), and implant-related complications including periprosthetic joint infections (3.14 versus 2.63%; OR: 1.20, P = .279) were similar between patients lacking dental history. Expenditures were higher in patients who had a postoperative and preoperative dental history ($19,252 versus $19,363 versus 17,980; P < .001). CONCLUSION: Dental caries or implant placement may reflect overall worse medical condition resulting in more complications and higher costs after TKA. Dental history screening preoperatively may assist arthroplasty surgeons in minimizing complications.


Asunto(s)
Artroplastia de Reemplazo de Rodilla , Caries Dental , Implantes Dentales , Humanos , Artroplastia de Reemplazo de Rodilla/efectos adversos , Estudios Retrospectivos , Caries Dental/complicaciones , Caries Dental/epidemiología , Caries Dental/cirugía , Susceptibilidad a Caries Dentarias , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología , Tiempo de Internación , Readmisión del Paciente , Factores de Riesgo
2.
Zhonghua Yu Fang Yi Xue Za Zhi ; 57(10): 1674-1681, 2023 Oct 06.
Artículo en Zh | MEDLINE | ID: mdl-37859388

RESUMEN

The improvement of food labeling can improve consumers' health awareness, reduce the burden of chronic diseases on the health and economy, and promote the development of the healthy food industry. Disease Risk Reduction Claim has been developed in European Union and the U.S. for over 20 years, with mature management methods and experience, but it is still lacking in China. Learning and drawing on the international management experience of food disease risk reduction claims can assist China to establish food disease risk reduction claims and improve the food health claims and labeling system.


Asunto(s)
Industria de Alimentos , Etiquetado de Alimentos , Humanos , Estados Unidos , Unión Europea , China/epidemiología
3.
Lett Appl Microbiol ; 73(1): 26-30, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33786882

RESUMEN

Dendrobium viroid (DVd) was first reported in China in 2020, and it is the only viroid known to infect Orchidaceae family plants. In this study, we developed a simple reverse transcription-polymerase chain reaction (RT-PCR) method for the rapid detection of DVd in Dendrobium plants. When extracting the sap template from the leaves, they are first clamped between two layers of plastic film, and the sap is pressed out and collected with a pipette. Using this sap, DVd was detected by dot-blot and RT-PCR methods and, the expected amplicons were confirmed by sequencing analysis. The batch analysis of field samples revealed that this method can be used to detect DVd rapidly. The detection method also reduces cross-contamination between different samples and minimizes false positives. Thus, this sap-direct RT-PCR method allows effective and rapid DVd detection in the study of Orchidaceae plants.


Asunto(s)
Dendrobium/virología , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Viroides/genética , Virología/métodos , China , Transcripción Reversa , Viroides/aislamiento & purificación
4.
Allergol Immunopathol (Madr) ; 48(3): 306-312, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31477390

RESUMEN

Over the past three decades, the number of obese people has risen steadily. The chronic low-grade inflammatory state and the non-specific activation of the immune system have contributed greatly to the development of obesity-related immunology. Food allergy as a kind of inflammatory disease with abnormal immune response may be associated with obesity. This review begins with the pro-inflammatory immunological effects of adipose tissue in obesity, and explains the possible effects of obesity on food allergy. In short, obesity not only directly causes imbalance of allergic-related immune cells in adipose tissue, but also indirectly causes this consequence through affecting expression of adipocytokines and peroxisome proliferator-activated receptor gamma (PPARγ) in adipose tissue. As a result, circulating levels of pro-inflammatory factors which are partly derived from adipose tissue increase, which might cause intestinal barrier injury. Therefore, obesity may increase the risk of food allergy.


Asunto(s)
Tejido Adiposo/metabolismo , Hipersensibilidad a los Alimentos/inmunología , Mediadores de Inflamación/metabolismo , Intestinos/patología , Obesidad/inmunología , Adipoquinas/metabolismo , Alérgenos/inmunología , Animales , Alimentos , Humanos , Inflamación , PPAR gamma/metabolismo
5.
Ann Oncol ; 30(1): 85-95, 2019 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-30371735

RESUMEN

Background: Early cancer diagnosis might improve survival rates. As circulating tumor DNA (ctDNA) carries cancer-specific modifications, it has great potential as a noninvasive biomarker for detection of incipient tumors. Patients and methods: We collected cell-free DNA (cfDNA) samples of 1002 elderly without a prior malignancy, carried out whole-genome massive parallel sequencing and scrutinized the mapped sequences for the presence of (sub)chromosomal copy number alterations (CNAs) predictive for a malignancy. When imbalances were detected, 6-monthly clinical follow-up was carried out. Results: In 3% of participants chromosomal imbalances were detected. Follow-up analyses, including whole-body MRI screening, confirmed the presence of five hematologic malignancies: one Hodgkin lymphoma (HL), stage II; three non-HL (type chronic lymphocytic leukemia, Rai I-Binet A; type SLL, stage III; type mucosa-associated lymphoid tissue, stage I) and one myelodysplastic syndrome with excess blasts, stage II. The CNAs detected in cfDNA were tumor-specific. Furthermore, one case was identified with monoclonal B-cell lymphocytosis, a potential precursor of B-cell malignancy. In 24 additional individuals, CNAs were identified but no cancer diagnosis was made. For 9 of them, the aberrant cfDNA profile originated from peripheral blood cells. For 15 others the origin of aberrations in cfDNA remains undetermined. Conclusion(s): Genomewide profiling of cfDNA in apparently healthy individuals enables the detection of incipient hematologic malignancies as well as clonal mosaicism with unknown clinical significance. CNA screening of cellular DNA of peripheral blood in elderly has established that clonal mosaicism for these chromosomal anomalies predicts a 5- to 10-fold enhanced risk of a subsequent cancer. We demonstrate that cfDNA screening detects CNAs, which are not only derived from peripheral blood, but even more from other tissues. Since the clinical relevance of clonal mosaics in other tissues remains unknown, long-term follow-up is warranted. Taken together, this study demonstrates that genomewide cfDNA analysis has potential as an unbiased screening approach for hematological malignancies and premalignant conditions.


Asunto(s)
ADN Tumoral Circulante/análisis , Variaciones en el Número de Copia de ADN , ADN de Neoplasias/análisis , Detección Precoz del Cáncer/métodos , Neoplasias/diagnóstico , Neoplasias/genética , Secuenciación Completa del Genoma/métodos , Anciano , Anciano de 80 o más Años , ADN Tumoral Circulante/genética , Estudios de Cohortes , ADN de Neoplasias/genética , Femenino , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Humanos , Masculino , Persona de Mediana Edad , Neoplasias/sangre , Pronóstico
6.
Osteoporos Int ; 30(3): 555-563, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30519756

RESUMEN

We performed a study to identify potential causes and risk factors of vertebral fracture cascade. Vertebral fracture cascade is a severe clinical event in patients with bone fragility. Only half of patients have an identified cause of secondary osteoporosis. INTRODUCTION: Vertebral fracture (VF) is the most common osteoporotic fracture, and a strong risk factor of subsequent VFs leading to VF cascade (VFC). We prompted a study to identify potential causes and risk factors of VFC. METHODS: VFC observations were collected retrospectively between January 2016 and April 2017. VFC was defined as an occurrence of at least three VFs within 1 year. RESULTS: We included in 10 centers a total of 113 patients with VFC (79.6% of women, median age 73, median number of VFs in the cascade, 5). We observed 40.5% and 30.9% of patients with previous major fractures and a previous VF, respectively, and 68.6% with densitometric osteoporosis; 18.9% of patients were currently receiving oral glucocorticoids and 37.1% in the past. VFC was attributed by the physician to postmenopausal osteoporosis in 54% of patients. A secondary osteoporosis associated with the VFC was diagnosed in 52 patients: glucocorticoid-induced osteoporosis (25.7%), non-malignant hemopathies (6.2%), alcoholism (4.4%), use of aromatase inhibitors (3.6%), primary hyperparathyroidism (2.7%), hypercorticism (2.7%), anorexia nervosa (2.7%), and pregnancy and lactation-associated osteoporosis (1.8%). A total of 11.8% of cases were reported following a vertebroplasty procedure. A total of 31.5% patients previously received an anti-osteoporotic treatment. In six patients, VFC occurred early after discontinuation of an anti-osteoporotic treatment, in the year after the last dose effect was depleted: five after denosumab and one after odanacatib. CONCLUSION: The results of this retrospective study showed that only half of VFC occurred in patients with a secondary cause of osteoporosis. Prospective studies are needed to further explore the determinants of this severe complication of osteoporosis.


Asunto(s)
Fracturas Osteoporóticas/etiología , Fracturas de la Columna Vertebral/etiología , Anciano , Anciano de 80 o más Años , Conservadores de la Densidad Ósea/uso terapéutico , Femenino , Francia/epidemiología , Glucocorticoides/efectos adversos , Humanos , Masculino , Persona de Mediana Edad , Osteoporosis/complicaciones , Osteoporosis/tratamiento farmacológico , Osteoporosis/epidemiología , Osteoporosis Posmenopáusica/complicaciones , Osteoporosis Posmenopáusica/tratamiento farmacológico , Osteoporosis Posmenopáusica/epidemiología , Fracturas Osteoporóticas/epidemiología , Recurrencia , Estudios Retrospectivos , Factores de Riesgo , Fracturas de la Columna Vertebral/epidemiología
7.
Allergol Immunopathol (Madr) ; 47(5): 506-512, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31248582

RESUMEN

Hypersensitivity occurs when the body is stimulated by an antigen, resulting in an immune response, and leads to a physiological disorder or abnormal tissue trauma. Various immune cells, cytokines, and inflammatory mediators are involved in the immune responses related to allergic diseases, which are the core of anaphylaxis. Estrogen receptors are widely distributed in immune cells, which combine with estrogen and participate in allergic responses by affecting immune cells, cytokines, and inflammatory factors. We aimed to summarize the association between estrogen and allergic reactions to provide a scientific basis for understanding and studying the mechanisms of allergic diseases.


Asunto(s)
Anafilaxia/metabolismo , Estrógenos/metabolismo , Hipersensibilidad/inmunología , Mastocitos/inmunología , Receptores de Estrógenos/metabolismo , Células Th2/inmunología , Animales , Citocinas/metabolismo , Humanos , Inmunidad Celular , Mediadores de Inflamación/metabolismo , Transducción de Señal
8.
Osteoporos Int ; 29(11): 2389-2397, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-29909470

RESUMEN

Inflammatory bowel diseases (IBDs) are associated with a decreased bone mineral density, but the impact on fractures is unknown. In our study, global risk of fracture is increased for patients with IBDs versus controls. This result will help to determine the appropriate assessment with early screening and management of osteoporosis. Inflammatory bowel diseases (IBDs), such as Crohn's disease (CD) and ulcerative colitis (UC), are associated with a decreased bone mineral density (BMD). However, the impact on fracture risk is unknown and data are contradictory across studies. In this systematic review and meta-analysis, we aimed to assess the risk of fracture and presence of low BMD in patients with IBDs compared to healthy controls. A systematic search of literature was conducted of MEDLINE, EMBASE, the Cochrane library and abstracts from appropriate scientific congresses. Studies were selected if they compared the incidence of fractures and/or BMD measurement by dual-energy X-ray absorptiometry in patients with IBDs and healthy sex- and age-matched controls. Data were extracted by two independent investigators. Meta-analysis was performed with the inverse variance approach to estimate pooled odds ratios (ORs) and risk ratios (RRs) with their 95% confidence intervals (CIs). Twenty-four studies met the inclusion criteria. On the basis of nine studies, global risk of fracture was increased for patients with IBDs versus controls (RR = 1.38, 95% CI 1.11-1.73; p = 0.005). Fracture risk with IBDs was significantly increased for vertebral fractures (OR = 2.26, 95% CI 1.04-4.90; p < 0.001), but not for any other site. The analysis of 16 studies evaluating BMD showed a significant decrease in mean BMD and Z-scores for IBD patients versus controls at all sites. In our meta-analysis, patients with IBDs have an increased risk of fractures, especially in the spine, and significant decreased BMD at all sites, which suggests the need for identifying high-risk individuals among this population.


Asunto(s)
Enfermedades Inflamatorias del Intestino/complicaciones , Osteoporosis/etiología , Fracturas Osteoporóticas/etiología , Densidad Ósea/fisiología , Humanos , Enfermedades Inflamatorias del Intestino/epidemiología , Enfermedades Inflamatorias del Intestino/fisiopatología , Osteoporosis/epidemiología , Osteoporosis/fisiopatología , Fracturas Osteoporóticas/epidemiología , Fracturas Osteoporóticas/fisiopatología , Medición de Riesgo/métodos
9.
J Biol Regul Homeost Agents ; 31(1): 157-162, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28337886

RESUMEN

This study analyzes the performance of SBA-15 mesoporous particles carrying oxytocin (OT) in promoting osteogenesis in vitro and in vivo. The SBA-15 particles synthesized in the previous studies (about 30 µm in diameter and containing 10 nm deep pores) were loaded with the drug oxytocin and cultured with human osteosarcoma MG-63 cell line in vitro. The influence of particles on cell proliferation was studied. The level of the osteogenic marker (alkaline phosphatase and type I collagen) was measured. For in vivo studies, the connectivity defects of rabbit skull were prepared, and SBA-15 suspensions were regularly injected at the defect sites. The changes in the defect site calcium salt deposition were measured, and morphological changes were observed by microscopy. The material had to promote effect on osteogenesis-related indicators such as alkaline phosphatase and collagen I in bone sarcoma cell line MG-63. In vivo, the calcium salt deposition in OT/SBA-15 group was significantly higher than in the blank group. SBA-15 carriers appeared to persist in the region of the defect after the injection and release the drugs slowly, thus playing a more distinct role in promoting bone repair of local bone defects. The results showed that SBA-15 particles with OT could slow the release drugs and could help in promoting osteogenesis.


Asunto(s)
Preparaciones de Acción Retardada/metabolismo , Portadores de Fármacos/metabolismo , Osteoblastos/efectos de los fármacos , Osteogénesis/efectos de los fármacos , Oxitócicos/farmacología , Oxitocina/farmacología , Dióxido de Silicio/metabolismo , Fosfatasa Alcalina/genética , Fosfatasa Alcalina/metabolismo , Animales , Biomarcadores/metabolismo , Calcificación Fisiológica/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Colágeno Tipo I/genética , Colágeno Tipo I/metabolismo , Preparaciones de Acción Retardada/química , Portadores de Fármacos/química , Expresión Génica , Humanos , Osteoblastos/citología , Osteoblastos/metabolismo , Tamaño de la Partícula , Conejos , Dióxido de Silicio/química , Cráneo/efectos de los fármacos , Cráneo/lesiones , Cráneo/metabolismo
10.
Nature ; 474(7350): 184-7, 2011 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-21633355

RESUMEN

During magnetic reconnection, the field lines must break and reconnect to release the energy that drives solar and stellar flares and other explosive events in space and in the laboratory. Exactly how this happens has been unclear, because dissipation is needed to break magnetic field lines and classical collisions are typically weak. Ion-electron drag arising from turbulence, dubbed 'anomalous resistivity', and thermal momentum transport are two mechanisms that have been widely invoked. Measurements of enhanced turbulence near reconnection sites in space and in the laboratory support the anomalous resistivity idea but there has been no demonstration from measurements that this turbulence produces the necessary enhanced drag. Here we report computer simulations that show that neither of the two previously favoured mechanisms controls how magnetic field lines reconnect in the plasmas of greatest interest, those in which the magnetic field dominates the energy budget. Rather, we find that when the current layers that form during magnetic reconnection become too intense, they disintegrate and spread into a complex web of filaments that causes the rate of reconnection to increase abruptly. This filamentary web can be explored in the laboratory or in space with satellites that can measure the resulting electromagnetic turbulence.

11.
Clin Exp Rheumatol ; 33(6): 851-7, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26411931

RESUMEN

OBJECTIVES: Nowadays, the recommended measures for optimal monitoring of axial Spondyloarthritis (ax-SpA) disease activity are either BASDAI and CRP, or ASDAS-CRP. However, there could be a gap between recommendations and daily practice. We aimed to determine the measures collected by rheumatologists in an ax-SpA follow-up visit, and to determine the impact of a meeting (where rheumatologists reached a consensus on the measures to be collected) on the collection of such measures. METHODS: A consensual meeting of a local network of 32 rheumatologists proposed, four months later, to report at least the BASDAI score in the medical file of every ax-SpA patient at every follow-up visit. An independent investigator reviewed the medical files of 10 consecutive patients per rheumatologist, seen twice during the year (e.g. before and after the meeting). The most frequently collected measures were assessed, and then, the frequency of collection before and after the meeting was compared. RESULTS: A total of 456 medical files from 228 patients were reviewed. Treatment (>60%), CRP (51.3%) and total BASDAI (28.5%) were the most reported measures in medical files. Before/After the meeting, the frequencies of collected measures in medical files were 28.5%/51.7%, 51.3%/52.2%, 16.7%/31.6% and 0.9%/6.1% for BASDAI, CRP, BASDAI + CRP and ASDAS, respectively reaching a statistically significance for BASDAI, ASDAS and BASDAI+CRP (p<0.05). CONCLUSIONS: This study revealed a low rate of systematic report of the recommended outcome measures in ax-SpA. However, it suggests that a consensual meeting involving practicing rheumatologists might be relevant to improve the implementation of such recommendations.


Asunto(s)
Evaluación de Procesos y Resultados en Atención de Salud , Reumatología , Espondilitis Anquilosante , Adulto , Femenino , Francia , Encuestas de Atención de la Salud , Necesidades y Demandas de Servicios de Salud , Indicadores de Salud , Humanos , Masculino , Persona de Mediana Edad , Evaluación de Procesos y Resultados en Atención de Salud/métodos , Evaluación de Procesos y Resultados en Atención de Salud/organización & administración , Mejoramiento de la Calidad , Reumatología/métodos , Reumatología/normas , Espondilitis Anquilosante/diagnóstico , Espondilitis Anquilosante/terapia
12.
Hum Reprod ; 29(6): 1238-43, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24664129

RESUMEN

STUDY QUESTION: Does uterine peristalsis influence the chance of clinical pregnancy in an embryo transfer cycle? SUMMARY ANSWER: The uterine peristaltic wave frequency before embryo transfer is inversely related to the clinical pregnancy rates in fresh and frozen-thawed embryo transfer cycles. WHAT IS KNOWN ALREADY: Uterine peristalsis participates in regulating fluid migration after mock embryo transfer, but whether it could potentially influence pregnancy outcomes had remained unclear. STUDY DESIGN, SIZE, DURATION: This prospective cohort study included a total of 292 infertile women and was conducted between March 2013 and August 2013. PARTICIPANTS/MATERIALS, SETTING, METHODS: Patients underwent fresh embryo transfer in a fresh stimulation cycle with a long down-regulation protocol, a natural frozen-thawed embryo transfer cycle or an artificial frozen-thawed embryo transfer cycle. Uterine peristaltic activity was assessed before embryo transfer by transvaginal ultrasonography. MAIN RESULTS AND THE ROLE OF CHANCE: The uterine peristaltic wave frequencies of most patients were between 1.1 and 3.0 waves/min before embryo transfer (ET). The clinical pregnancy rate was the highest when <2.0 waves/min was observed and it decreased with an increasing wave frequency thereafter, with an especially dramatic decrease with >3.0 waves/min. Uterine peristaltic wave frequencies of the non-pregnant patient group were higher than that of the clinically-pregnant patient group in all types of transfer, fresh embryo transfer, natural FET or artificial FET cycle. Binary logistic regression analysis demonstrated that the association between uterine peristaltic wave frequency before embryo transfer and clinical pregnancy was independently significant (odds ratio: 0.49; 95% confidence interval: 0.34-0.70, P < 0.001). LIMITATIONS, REASONS FOR CAUTION: Uterine peristalsis after embryo transfer was not observed in case any possible negative effect of the observation disturbed embryo implantation or caused psychological stress. Uterine peristalsis after embryo transfer may differ from that before embryo transfer. Another limitation of the present study was the lack of uterine peristaltic wave type analysis which is also an important parameter to assess uterine activity. WIDER IMPLICATIONS OF THE FINDINGS: Patients with uterine peristalsis of <3.0 waves/min before embryo transfer had a higher chance of pregnancy compared with those with higher frequencies. This could be a promising quantitative marker of uterine receptivity and pregnancy outcome in an embryo transfer cycle. The predictive validity of the cut-off value needs to be tested in further study. STUDY FUNDING/COMPETING INTEREST(S): The study is supported by Hunan Provincial Innovation Foundation for Postgraduates. The authors declare that they have no competing interests in this study.


Asunto(s)
Transferencia de Embrión , Infertilidad Femenina/terapia , Peristaltismo/fisiología , Útero/fisiopatología , Adulto , Estudios de Cohortes , Femenino , Humanos , Infertilidad Femenina/fisiopatología , Inducción de la Ovulación , Embarazo , Resultado del Embarazo , Índice de Embarazo , Estudios Prospectivos
13.
Hum Reprod ; 29(2): 279-85, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24277748

RESUMEN

STUDY QUESTION: What is the effect of uterine peristalsis on fluid migration after mock embryo transfer? SUMMARY ANSWER: Uterine peristaltic wave frequency was positively correlated with the distance that fluid moved after it was deposited in the uterine cavity. WHAT IS KNOWN ALREADY: Embryos have been found outside the uterine cavity after embryo transfer. It has been suggested that uterine contractions expelled these embryos. STUDY DESIGN, SIZE, DURATION: A prospective cohort study of a total of 112 infertile women was conducted between March 2013 and May 2013. PARTICIPANTS/MATERIALS, SETTING, METHODS: Uterine peristaltic activity was assessed before and after a mock embryo transfer, in which 20 µl of ultrasound contrast agent was placed in the uterine lumen 3 days after ovulation in a natural cycle. The movement of this fluid was measured by ultrasound at 0, 15 and 30 min after placement. MAIN RESULTS AND THE ROLE OF CHANCE: The uterine peristaltic wave frequency was significantly higher after than before mock transfer (3.06 ± 0.99 versus 2.24 ± 0.74, P < 0.01). At the conclusion of the 30-min monitoring period, the fluid had remained in place (N = 94), leaked into the cervix (N = 5), or moved into the Fallopian tubes or the cornua of the uterus (N = 11). The fluid movement was positively correlated with uterine peristaltic wave frequencies before (r = 0.518, P < 0.01) and after embryo transfer (r = 0.371, P < 0.01) and uterine peristaltic wave frequency was significantly higher both before and after embryo transfer in cases where the fluid was extruded. LIMITATIONS, REASONS FOR CAUTION: Mock embryo transfer was performed in the luteal phase of a natural cycle instead of a controlled ovarian stimulation cycle. The endometrial environment and uterine peristalsis may be different in a stimulated cycle. WIDER IMPLICATIONS OF THE FINDINGS: Uterine peristalsis exerts control over embryo migration and could adversely affect the chances of pregnancy if the wave frequency is too high. It could be used as a predictor of uterine irritability before embryo transfer. STUDY FUNDING/COMPETING INTEREST(S): The authors declare that they have not received any particular study funding and do not have competing interests in this study.


Asunto(s)
Transferencia de Embrión/métodos , Peristaltismo/fisiología , Útero/diagnóstico por imagen , Útero/fisiología , Medios de Contraste/química , Implantación del Embrión/fisiología , Endometrio/diagnóstico por imagen , Femenino , Humanos , Ovulación , Inducción de la Ovulación , Embarazo , Estudios Prospectivos , Programas Informáticos , Factores de Tiempo , Ultrasonografía , Útero/patología
14.
Phys Rev Lett ; 112(6): 061101, 2014 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-24580684

RESUMEN

The observed steep kinetic scale turbulence spectrum in the solar wind raises the question of how that turbulence originates. Observations of keV energetic electrons during solar quiet time suggest them as a possible source of free energy to drive kinetic turbulence. Using particle-in-cell simulations, we explore how the free energy released by an electron two-stream instability drives Weibel-like electromagnetic waves that excite wave-wave interactions. Consequently, both kinetic Alfvénic and whistler turbulence are excited that evolve through inverse and forward magnetic energy cascades.

15.
Nature ; 443(7111): 553-6, 2006 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-17024088

RESUMEN

A long-standing problem in the study of space and astrophysical plasmas is to explain the production of energetic electrons as magnetic fields 'reconnect' and release energy. In the Earth's magnetosphere, electron energies reach hundreds of thousands of electron volts (refs 1-3), whereas the typical electron energies associated with large-scale reconnection-driven flows are just a few electron volts. Recent observations further suggest that these energetic particles are produced in the region where the magnetic field reconnects. In solar flares, upwards of 50 per cent of the energy released can appear as energetic electrons. Here we show that electrons gain kinetic energy by reflecting from the ends of the contracting 'magnetic islands' that form as reconnection proceeds. The mechanism is analogous to the increase of energy of a ball reflecting between two converging walls--the ball gains energy with each bounce. The repetitive interaction of electrons with many islands allows large numbers to be efficiently accelerated to high energy. The back pressure of the energetic electrons throttles reconnection so that the electron energy gain is a large fraction of the released magnetic energy. The resultant energy spectra of electrons take the form of power laws with spectral indices that match the magnetospheric observations.

16.
Phys Rev Lett ; 107(13): 135001, 2011 Sep 23.
Artículo en Inglés | MEDLINE | ID: mdl-22026861

RESUMEN

Previous 2D simulations of reconnection using a standard model of initially antiparallel magnetic fields have detected electron jets outflowing from the x point into the ion outflow exhausts. Associated with these jets are extended "outer electron diffusion regions." New PIC simulations with an ion to electron mass ratio as large as 1836 (an H(+) plasma) now show that the jets are strongly deflected and the outer electron diffusion region is broken up by a very weak out-of-plane magnetic guide field, even though the diffusion rate itself is unchanged. Jet outflow and deflection are interpreted in terms of electron dynamics and are compared to recent measurements of jets in the presence of a small guide field in Earth's magnetosheath.

17.
Nanotechnology ; 22(42): 425706, 2011 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-21941034

RESUMEN

The effects of Mg concentration and annealing temperature on the characteristics of nanocrystalline Mg(x)Zn(1 - x)O thin films (where x = 0-0.4) were studied using electron microscopy and photoluminescence. The films were prepared by a sol-gel method. The solid solubility limit of MgO in ZnO for the sol-gel-derived Mg(x)Zn(1 - x)O films in the present study was determined to be ∼ 20 at.%. Microstructural characterization of the films showed that the wurtzite crystallites decrease in size with increase in Mg concentration up to the solubility limit. Increasing Mg concentration beyond the solubility limit resulted in a decrease in crystallinity of the films. The bandgap energy was found to increase with Mg concentration whereas the linewidth first increased and then decreased when the Mg concentration was increased beyond the solubility limit. Photoluminescence properties have been correlated to the microstructure of the films. A growth mechanism for Mg(x)Zn(1 - x)O nanocrystalline films under the present processing conditions has also been proposed.

18.
Phytopathology ; 101(7): 859-69, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21323467

RESUMEN

A study was conducted to identify volatile organic compounds or volatiles produced by Candida intermedia strain C410 using gas chromatography-mass spectrometry, and to determine efficacy of the volatiles of C. intermedia in suppression of conidial germination and mycelial growth of Botrytis cinerea and control of Botrytis fruit rot of strawberry. Results showed that, among 49 volatiles (esters, alcohols, alkenes, alkanes, alkynes, organic acids, ketones, and aldehydes) identified from C. intermedia cultures on yeast extract peptone dextrose agar, two compounds, 1,3,5,7-cyclooctatetraene and 3-methyl-1-butanol, were the most abundant. Synthetic chemicals of 1,3,5,7-cyclooctatetraene; 3-methyl-1-butanol; 2-nonanone; pentanoic acid, 4-methyl-, ethyl ester; 3-methyl-1-butanol, acetate; acetic acid, pentyl ester; and hexanoic acid, ethyl ester were highly inhibitory to conidial germination and mycelial growth of B. cinerea. Inhibition of conidial germination and mycelial growth of B. cinerea by volatiles of C. intermedia was also observed. Meanwhile, results showed that incidence and severity of Botrytis fruit rot of strawberry was significantly (P < 0.01) reduced by exposure of the strawberry fruit to the volatiles from C. intermedia cultures or C. intermedia-infested strawberry fruit. These results suggest that the volatiles of C. intermedia C410 are promising biofumigants for control of Botrytis fruit rot of strawberry.


Asunto(s)
Antifúngicos/farmacología , Botrytis/crecimiento & desarrollo , Candida/química , Fragaria/microbiología , Enfermedades de las Plantas/microbiología , Compuestos Orgánicos Volátiles/farmacología , Antifúngicos/clasificación , Bioensayo , Botrytis/efectos de los fármacos , Botrytis/patogenicidad , Candida/crecimiento & desarrollo , Frutas/microbiología , Cromatografía de Gases y Espectrometría de Masas/métodos , Micelio/efectos de los fármacos , Micelio/crecimiento & desarrollo , Esporas Fúngicas/efectos de los fármacos , Esporas Fúngicas/crecimiento & desarrollo , Compuestos Orgánicos Volátiles/clasificación
19.
J Dairy Sci ; 94(2): 676-83, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21257036

RESUMEN

Food components with the ability to suppress preadipocyte proliferation and intracellular lipid accumulation may be helpful in the prevention of obesity, which is a worldwide health concern. Casein glycomacropeptide (GMP), which has pronounced gastric inhibitory activity, could potentially possess fat synthesis inhibition properties and an obesity-alleviating capacity. The objective of the present study was to investigate the effect of GMP on the proliferation and differentiation of preadipocytes as well as triglyceride accumulation and glycerol-3-phosphate dehydrogenase activity in preadipocytes isolated from Sprague-Dawley rats. Different dosages (0, 0.31, 0.625, 1.25, 2.5, and 5.0 mg/mL) of GMP were co-incubated with preadipocytes. The proliferation activity of preadipocytes significantly decreased in the GMP-treated group compared with that of the control group without GMP supplementation. The GMP exhibited an inhibitory effect against preadipocyte proliferation in a dose-dependent manner; the maximal antiproliferative effect was obtained with 2.5 mg/mL. The GMP also attenuated differentiation, as revealed by decreased lipid content, and the effect was more pronounced when cells were treated with GMP before or at the beginning of differentiation induction than at later stages of cell differentiation. Cultured preadipocytes treated with GMP accumulated fewer triglycerides and had lower glycerol-3-phosphate dehydrogenase activity than did the control cells without GMP supplementation. In conclusion, GMP can inhibit the proliferation, differentiation, and lipid accumulation of preadipocytes in vitro.


Asunto(s)
Adipocitos/efectos de los fármacos , Caseínas/farmacología , Diferenciación Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Metabolismo de los Lípidos/efectos de los fármacos , Adipocitos/fisiología , Animales , Células Cultivadas , Técnicas In Vitro , Masculino , Ratas , Ratas Sprague-Dawley
20.
Nan Fang Yi Ke Da Xue Xue Bao ; 41(11): 1600-1608, 2021 Nov 20.
Artículo en Zh | MEDLINE | ID: mdl-34916184

RESUMEN

OBJECTIVE: To explore the correlation of triglyceride-glucose product (TyG) index with chronic kidney disease (CKD) in elderly population in Lanzhou (Gansu Province, China). METHODS: From May to September, 2011, a total of 3868 middleaged and elderly individuals without CKD from 3 communities in Lanzhou were selected as the cohort study population and were followed for an average of 3.1 years (from June, 2014 to August, 2015). After excluding those with missing follow-up data, a total of 3439 individuals were included for analysis, who were divided according to the quartile of TyG index into Q1 group (TyG≤8.47), Q2 group (TyG 8.48-8.84), Q3 group (TyG 8.85-9.20) and Q4 group (TyG>9.20). The estimated glomerular filtration rate (eGFR) and urinary albumin/creatinine ratio (UACR) were used to evaluate the renal function of the participants. RESULTS: In this cohort, a high TyG index was found to correlate with a high risk of CKD (P < 0.05). Analysis of the follow-up data showed that the TyG index was significantly higher in patients who developed CKD during the follow-up than in those without CKD (P < 0.05). Logistic regression analysis showed that TyG index was an independent risk factor for abnormal eGFR and CKD (P < 0.05). CONCLUSION: A high TyG index is an independent risk factor for CKD in middle-aged and elderly population.


Asunto(s)
Glucosa , Insuficiencia Renal Crónica , Anciano , China/epidemiología , Humanos , Persona de Mediana Edad , Estudios Prospectivos , Insuficiencia Renal Crónica/epidemiología , Triglicéridos
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