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1.
J Acquir Immune Defic Syndr ; 93(5): 395-402, 2023 08 15.
Artículo en Inglés | MEDLINE | ID: mdl-37104739

RESUMEN

BACKGROUND: Women with HIV in high-income settings have increasingly expressed a desire to breastfeed their infants. Although national guidelines now acknowledge this choice, detailed recommendations are not available. We describe the approach to managing care for breastfeeding women with HIV at a single large-volume site in the United States. METHODS: We convened an interdisciplinary group of providers to establish a protocol intended to minimize the risk of vertical transmission during breastfeeding. Programmatic experience and challenges are described. A retrospective chart review was conducted to report the characteristics of women who desired to or who did breastfeed between 2015 and 2022 and their infants. RESULTS: Our approach stresses the importance of early conversations about infant feeding, documentation of feeding decisions and management plans, and communication among the health care team. Mothers are encouraged to maintain excellent adherence to antiretroviral treatment, maintain an undetectable viral load, and breastfeed exclusively. Infants receive continuous single-drug antiretroviral prophylaxis until 4 weeks after cessation of breastfeeding. From 2015 to 2022, we counseled 21 women interested in breastfeeding, of whom 10 women breastfed 13 infants for a median of 62 days (range, 1-309). Challenges included mastitis (N = 3), need for supplementation (N = 4), maternal plasma viral load elevation of 50-70 copies/mL (N = 2), and difficulty weaning (N = 3). Six infants experienced at least 1 adverse event, most of which were attributed to antiretroviral prophylaxis. DISCUSSION: Many knowledge gaps remain in the management of breastfeeding among women with HIV in high-income settings, including approaches to infant prophylaxis. An interdisciplinary approach to minimizing risk is needed.


Asunto(s)
Lactancia Materna , Infecciones por VIH , Lactante , Femenino , Niño , Estados Unidos , Humanos , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/prevención & control , Colorado , Estudios Retrospectivos , Antirretrovirales/uso terapéutico , Transmisión Vertical de Enfermedad Infecciosa/prevención & control , Hospitales
2.
Science ; 378(6621): eabg3679, 2022 Nov 18.
Artículo en Inglés | MEDLINE | ID: mdl-36395225

RESUMEN

The Hippo signaling pathway is widely considered a master regulator of organ growth because of the prominent overgrowth phenotypes caused by experimental manipulation of its activity. Contrary to this model, we show here that removing Hippo transcriptional output did not impair the ability of the mouse liver and Drosophila eyes to grow to their normal size. Moreover, the transcriptional activity of the Hippo pathway effectors Yap/Taz/Yki did not correlate with cell proliferation, and hyperactivation of these effectors induced gene expression programs that did not recapitulate normal development. Concordantly, a functional screen in Drosophila identified several Hippo pathway target genes that were required for ectopic overgrowth but not normal growth. Thus, Hippo signaling does not instruct normal growth, and the Hippo-induced overgrowth phenotypes are caused by the activation of abnormal genetic programs.


Asunto(s)
Drosophila melanogaster , Ojo , Regulación del Desarrollo de la Expresión Génica , Vía de Señalización Hippo , Hígado , Transcripción Genética , Proteínas Coactivadoras Transcripcionales con Motivo de Unión a PDZ , Proteínas Señalizadoras YAP , Animales , Ratones , Drosophila melanogaster/embriología , Drosophila melanogaster/genética , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Ojo/embriología , Vía de Señalización Hippo/genética , Hígado/embriología , Tamaño de los Órganos , Proteínas Serina-Treonina Quinasas/genética , Proteínas Serina-Treonina Quinasas/metabolismo , Transactivadores/genética , Proteínas Coactivadoras Transcripcionales con Motivo de Unión a PDZ/metabolismo , Proteínas Señalizadoras YAP/metabolismo
3.
Facts Views Vis Obgyn ; 14(3): 265-273, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-36206801

RESUMEN

Background: Ovarian cancer cytoreductive surgery necessitates the use of advanced Simulation-Based Learning (SBL) to optimise skill-based teaching and achieve technical proficiency. Objective: We describe and appraise the role of a novel postgraduate cadaveric course for cytoreductive surgery for advanced ovarian/fallopian tube or primary peritoneal cancer. Materials and Methods: Several consultant-level surgeons with expertise in upper gastrointestinal, colorectal, hepatobiliary and urological surgery, were invited to teach their counterpart gynaecological oncology (GO) surgeons. The 2-day course curriculum involved advanced dissections on thiel-embalmed cadavers. All dissections included applicable steps required during GO cytoreductive surgeries. Outcome measures: We used a feedback questionnaire and structured interviews to capture trainers and delegates views respectively. Results: All delegates reported a positive educational experience and improvement of knowledge in all course components. There was no difference in the perception of feedback across junior versus senior consultants. Trainers perceived this opportunity as a "2-way learning" whether they got to explore in depth the GO perspective in how and which of their skills are applicable during cytoreductive surgery. Conclusions: Collaborating with other surgical specialities promotes a "learning from the experts" concept and has potential to meet the rapidly increased demand for multi-viscera surgical excellence in GO surgery. What's new?: The concept of involving experts from other surgical disciplines in advanced cadaveric courses for cytoreductive surgery in ovarian cancer, will solidify the effort to achieve excellence in the GO training. Such courses can be essential educational adjunct for most GO fellowships.

4.
Br J Anaesth ; 116(2): 163-76, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26787787

RESUMEN

BACKGROUND: This systematic review evaluated the evidence comparing patient-important outcomes in spinal or epidural vs general anaesthesia for total hip and total knee arthroplasty. METHODS: MEDLINE, Ovid EMBASE, EBSCO CINAHL, Thomson Reuters Web of Science, and the Cochrane Central Register of Controlled Trials from inception until March 2015 were searched. Eligible randomized controlled trials or prospective comparative studies investigating mortality, major morbidity, and patient-experience outcomes directly comparing neuraxial (spinal or epidural) with general anaesthesia for total hip arthroplasty, total knee arthroplasty, or both were included. Independent reviewers working in duplicate extracted study characteristics, validity, and outcomes data. Meta-analysis was conducted using the random-effects model. RESULTS: We included 29 studies involving 10 488 patients. Compared with general anaesthesia, neuraxial anaesthesia significantly reduced length of stay (weighted mean difference -0.40 days; 95% confidence interval -0.76 to -0.03; P=0.03; I2 73%; 12 studies). No statistically significant differences were found between neuraxial and general anaesthesia for mortality, surgical duration, surgical site or chest infections, nerve palsies, postoperative nausea and vomiting, or thromboembolic disease when antithrombotic prophylaxis was used. Subgroup analyses failed to find statistically significant interactions (P>0.05) based on risk of bias, type of surgery, or type of neuraxial anaesthesia. CONCLUSION: Neuraxial anaesthesia for total hip or total knee arthroplasty, or both appears equally effective without increased morbidity when compared with general anaesthesia. There is limited quantitative evidence to suggest that neuraxial anaesthesia is associated with improved perioperative outcomes. Future investigations should compare intermediate and long-term outcome differences to better inform anaesthesiologists, surgeons, and patients on importance of anaesthetic selection.


Asunto(s)
Anestesia Epidural/estadística & datos numéricos , Anestesia General/estadística & datos numéricos , Anestesia Raquidea/estadística & datos numéricos , Artroplastia de Reemplazo de Cadera , Artroplastia de Reemplazo de Rodilla , Investigación sobre la Eficacia Comparativa/estadística & datos numéricos , Humanos , Tiempo de Internación/estadística & datos numéricos , Complicaciones Posoperatorias/epidemiología , Estudios Prospectivos , Ensayos Clínicos Controlados Aleatorios como Asunto , Resultado del Tratamiento
5.
Aliment Pharmacol Ther ; 42(2): 231-8, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-26011446

RESUMEN

BACKGROUND: Proton pump inhibitor-responsive oesophageal eosinophilia (PPI-REE) is a recently described entity which resembles oeosinophilic oesophagitis (EoE), yet responds to acid suppressive treatment. AIM: To determine whether EoE shares similar staining features with PPI-REE or with gastro-oesophageal reflux disease (GERD). METHODS: This retrospective study consisted of patients with an established diagnosis of EoE, PPI-REE, or GERD identified from a database during a 1-year period. Immunohistochemistry (IHC) analysis was performed specifically targeting eotaxin-3 antibodies. All sections were qualitatively (intensity) and quantitatively (percentage of cells stained) assessed independently by two blinded pathologists. RESULTS: The cohort consisted of three groups of patients: EoE (n = 22), PPI-REE (n = 23) and GERD (n = 23) for a total of 68 patients. Study demographics included mean age 39 (14) years, 75% male and 77% Caucasian. There was a significant difference in the eotaxin-3 staining among EoE, PPI-REE and GERD groups [mean score (s.d.): 1.2 (1.2), 0.8 (1.0), 0.3 (0.7), P = 0.006]. Staining scores of EoE patients were significantly higher compared with GERD (P = 0.002) and a trend towards significance was seen between EoE and PPI-REE (P = 0.054). There was also a significant difference in EoE staining intensity score among the three groups (P = 0.006). Intensity scores of EoE were significantly higher compared with GERD [1.0 (0.9) vs. 0.22 (0.52), P < 0.001]. There was no significant difference between EoE and PPI-REE groups [1.0 (0.0) vs. 0.52 (0.75) P = 0.094]. CONCLUSIONS: A difference in eotaxin-3 staining was seen in the three groups of patients with oesophageal eosinophilia. Eotaxin-3 can distinguish EoE from GERD, but not from proton pump inhibitor responsive-oesophageal eosinophilia.


Asunto(s)
Quimiocinas CC/inmunología , Esofagitis Eosinofílica/diagnóstico , Esofagitis Eosinofílica/patología , Reflujo Gastroesofágico/patología , Adulto , Biomarcadores , Quimiocina CCL26 , Diagnóstico Diferencial , Esofagitis Eosinofílica/tratamiento farmacológico , Femenino , Reflujo Gastroesofágico/diagnóstico , Humanos , Inmunohistoquímica , Masculino , Persona de Mediana Edad , Inhibidores de la Bomba de Protones/uso terapéutico , Estudios Retrospectivos
6.
J Physiol ; 592(22): 5079-92, 2014 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-25217379

RESUMEN

G protein signalling within the central circadian oscillator, the suprachiasmatic nucleus (SCN), is essential for conveying time-of-day information. We sought to determine whether G protein-coupled inwardly rectifying potassium channels (GIRKs) modulate SCN physiology and circadian behaviour. We show that GIRK current and GIRK2 protein expression are greater during the day. Pharmacological inhibition of GIRKs and genetic loss of GIRK2 depolarized the day-time resting membrane potential of SCN neurons compared to controls. Behaviourally, GIRK2 knockout (KO) mice failed to shorten free running period in response to wheel access in constant darkness and entrained more rapidly to a 6 h advance of a 12 h:12 h light-dark (LD) cycle than wild-type (WT) littermate controls. We next examined whether these effects were due to disrupted signalling of neuropeptide Y (NPY), which is known to mediate non-photic phase shifts, attenuate photic phase shifts and activate GIRKs. Indeed, GIRK2 KO SCN slices had significantly fewer silent cells in response to NPY, likely contributing to the absence of NPY-induced phase advances of PER2::LUC rhythms in organotypic SCN cultures from GIRK2 KO mice. Finally, GIRK channel activation is sufficient to cause a non-photic-like phase advance of PER2::LUC rhythms on a Per2(Luc+/-) background. These results suggest that rhythmic regulation of GIRK2 protein and channel function in the SCN contributes to day-time resting membrane potential, providing a mechanism for the fine tuning responses to non-photic and photic stimuli. Further investigation could provide insight into disorders with circadian disruption comorbidities such as epilepsy and addiction, in which GIRK channels have been implicated.


Asunto(s)
Ritmo Circadiano , Canales de Potasio Rectificados Internamente Asociados a la Proteína G/metabolismo , Núcleo Supraquiasmático/metabolismo , Animales , Canales de Potasio Rectificados Internamente Asociados a la Proteína G/genética , Potenciales de la Membrana , Ratones , Ratones Endogámicos C57BL , Neuronas/metabolismo , Neuronas/fisiología , Neuropéptido Y/metabolismo , Proteínas Circadianas Period/genética , Proteínas Circadianas Period/metabolismo , Núcleo Supraquiasmático/citología , Núcleo Supraquiasmático/fisiología
7.
Br J Anaesth ; 112(2): 231-45, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24368556

RESUMEN

Simulation has long been integrated in anaesthesiology training, yet a comprehensive review of its effectiveness is presently lacking. Using meta-analysis and critical narrative analysis, we synthesized the evidence for the effectiveness of simulation-based anaesthesiology training. We searched MEDLINE, ERIC, and SCOPUS through May 2011 and included studies using simulation to train health professional learners. Data were abstracted independently and in duplicate. We included 77 studies (6066 participants). Compared with no intervention (52 studies), simulation was associated with moderate to large pooled effect sizes (ESs) for all outcomes (ES range 0.60-1.05) except for patient effects (ES -0.39). Compared with non-simulation instruction (11 studies), simulation was associated with moderate effects for satisfaction and skills (ES 0.39 and 0.42, respectively), large effect for behaviours (1.77), and small effects for time, knowledge, and patient effects (-0.18 to 0.23). In 17 studies comparing alternative simulation interventions, training in non-technical skills (e.g. communication) and medical management compared with training in medical management alone was associated with negligible effects for knowledge and skills (four studies, ES range 0.14-0.15). Debriefing using multiple vs single information sources was associated with negligible effects for time and skills (three studies, ES range -0.07 to 0.09). Our critical analysis showed inconsistency in measurement of non-technical skills and consistency in the (ineffective) design of debriefing. Simulation in anaesthesiology appears to be more effective than no intervention (except for patient outcomes) and non-inferior to non-simulation instruction. Few studies have clarified the key instructional designs for simulation-based anaesthesiology training.


Asunto(s)
Anestesiología/educación , Simulación por Computador , Educación Médica/métodos , Humanos
8.
Mol Oncol ; 8(1): 142-9, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24210755

RESUMEN

PURPOSE: Operable thoracic esophageal/gastroesophageal junction carcinoma (EC) is often treated with chemoradiation and surgery but tumor responses are unpredictable and heterogeneous. We hypothesized that aldehyde dehydrogenase-1 (ALDH-1) could be associated with response. METHODS: The labeling indices (LIs) of ALDH-1 by immunohistochemistry in untreated tumor specimens were established in EC patients who had chemoradiation and surgery. Univariate logistic regression and 3-fold cross validation were carried out for the training (67% of patients) and validation (33%) sets. Non-clinical experiments in EC cells were performed to generate complimentary data. RESULTS: Of 167 EC patients analyzed, 40 (24%) had a pathologic complete response (pathCR) and 27 (16%) had an extremely resistant (exCRTR) cancer. The median ALDH-1 LI was 0.2 (range, 0.01-0.85). There was a significant association between pathCR and low ALDH-1 LI (p ≤ 0.001; odds-ratio [OR] = 0.432). The 3-fold cross validation led to a concordance index (C-index) of 0.798 for the fitted model. There was a significant association between exCRTR and high ALDH-1 LI (p ≤ 0.001; OR = 3.782). The 3-fold cross validation led to the C-index of 0.960 for the fitted model. In several cell lines, higher ALDH-1 LIs correlated with resistant/aggressive phenotype. Cells with induced chemotherapy resistance upregulated ALDH-1 and resistance conferring genes (SOX9 and YAP1). Sorted ALDH-1+ cells were more resistant and had an aggressive phenotype in tumor spheres than ALDH-1- cells. CONCLUSIONS: Our clinical and non-clinical data demonstrate that ALDH-1 LIs are predictive of response to therapy and further research could lead to individualized therapeutic strategies and novel therapeutic targets for EC patients.


Asunto(s)
Adenocarcinoma/patología , Adenocarcinoma/terapia , Neoplasias Esofágicas/patología , Neoplasias Esofágicas/terapia , Esófago/patología , Isoenzimas/análisis , Retinal-Deshidrogenasa/análisis , Adenocarcinoma/diagnóstico , Adenocarcinoma/genética , Adulto , Anciano , Anciano de 80 o más Años , Familia de Aldehído Deshidrogenasa 1 , Línea Celular Tumoral , Quimioradioterapia , Neoplasias Esofágicas/diagnóstico , Neoplasias Esofágicas/genética , Esófago/efectos de los fármacos , Esófago/metabolismo , Esófago/efectos de la radiación , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Inmunohistoquímica , Isoenzimas/genética , Masculino , Persona de Mediana Edad , Pronóstico , Retinal-Deshidrogenasa/genética
9.
Br J Anaesth ; 111(3): 338-46, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23611912

RESUMEN

Cricoid pressure (CP) is commonly applied during rapid sequence intubation and may be protective during induction of anaesthesia; however, CP application by untrained practitioners may not be performed optimally. The objective of this systematic review was to synthesize the evidence regarding effectiveness of technology-enhanced simulation training to improve efficacy of CP application. Electronic databases from inception through May 11, 2011 were searched. Eligible studies evaluated CP simulation training. Independent reviewers working in duplicate extracted study characteristics, validity, and outcomes data. Pooled effect size (ES) with 95% confidence intervals (CIs) were estimated from each study that compared technology-enhanced simulation with no intervention or with other methods of CP training using random-effects model. Twelve studies (772 trainees) evaluated CP training as an outcome. Nine studies reported information on baseline skill, with 23% of providers being able to achieve the target CP before training. In a meta-analysis of 10 studies (570 trainees), CP training resulted in a large favourable impact on skills among trainees compared with no intervention (pooled ES 1.18; 95% CI 0.85-1.51; P<0.0001). Four studies found evidence of skills retention for CP application after training, but for a limited time (<4 weeks). Comparative effectiveness research shows beneficial effects to force feedback training over training without feedback. Simulation training significantly improves the efficacy of CP application. Future studies might evaluate the clinical impact of training on CP application during rapid sequence intubation, and the comparative effectiveness of different training approaches.


Asunto(s)
Competencia Clínica , Cartílago Cricoides , Intubación Intratraqueal/métodos , Maniquíes , Palpación/métodos , Humanos
10.
Br J Anaesth ; 110(4): 518-28, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23440367

RESUMEN

The objective of this systematic review with meta-analysis was to determine the risk for falls after major orthopaedic surgery with peripheral nerve blockade. Electronic databases from inception through January 2012 were searched. Eligible studies evaluated falls after peripheral nerve blockade in adult patients undergoing major lower extremity orthopaedic surgery. Independent reviewers working in duplicate extracted study characteristics, validity, and outcomes data. The Peto odds ratio (OR) with 95% confidence intervals (CIs) were estimated from each study that compared continuous lumbar plexus blockade with non-continuous blockade or no blockade using a fixed effects model. Ten studies (4014 patients) evaluated the number of falls as an outcome. Five studies did not contain comparison groups. The meta-analysis of five studies [four randomized controlled trials (RCTs) and one cohort] compared continuous lumbar plexus blockade (631 patients) with non-continuous blockade or no blockade (964 patients). Fourteen falls occurred in the continuous lumbar plexus block group when compared with five falls within the non-continuous block or no block group (attributable risk 1.7%; number needed to harm 59). Continuous lumbar plexus blockade was associated with a statistically significant increase in the risk for falls [Peto OR 3.85; 95% CI (1.52, 9.72); P=0.005; I(2)=0%]. Evidence was low (cohort) to high (RCTs) quality. Continuous lumbar plexus blockade in adult patients undergoing major lower extremity orthopaedic surgery increases the risk for postoperative falls compared with non-continuous blockade or no blockade. However, attributable risk was not outside the expected probability of postoperative falls after orthopaedic surgery.


Asunto(s)
Accidentes por Caídas/estadística & datos numéricos , Bloqueo Nervioso/efectos adversos , Procedimientos Ortopédicos , Nervios Periféricos , Complicaciones Posoperatorias/epidemiología , Anciano , Artroplastia de Reemplazo de Cadera , Artroplastia de Reemplazo de Rodilla , Protocolos Clínicos , Estudios de Cohortes , Recolección de Datos , Femenino , Humanos , Extremidad Inferior/cirugía , Plexo Lumbosacro , Masculino , Persona de Mediana Edad , Ensayos Clínicos Controlados Aleatorios como Asunto , Resultado del Tratamiento
11.
J Parasitol ; 99(1): 102-11, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22920147

RESUMEN

Myxobolus stanlii sp. n. was described from largescale stonerollers ( Campostoma oligolepis ) from the Mobile River Basin in Alabama. The parasite was described using critical identifying morphological features, and the 18S small subunit ribosomal RNA (SSU rRNA) gene sequence. The spore body was ovoid, 10.03 ± 0.7 (7.5-11.0) µm long and 8.8 ± 1.5 (6.3-11.3) µm wide in frontal view. Spore thickness was 6.3 ± 2.7 (6.2-8.6) µm in sutural view. Polar capsules were pyriform, of equal size, and oriented in plane with the sutural ridge. Polar capsules were 2.45 ± 1.5 (range 2.1-4.3) µm in width and 4.6 ± 2.7 (range 4.5-6.9) µm in length. Based on the SSU rRNA gene sequence of Myxobolus stanlii sp. n. is most closely related to M. pseudodispar.


Asunto(s)
Cyprinidae/parasitología , Enfermedades de los Peces/parasitología , Myxozoa/clasificación , Enfermedades Parasitarias en Animales/parasitología , Alabama/epidemiología , Animales , Secuencia de Bases , ADN Ribosómico/química , Enfermedades de los Peces/epidemiología , Procesamiento de Imagen Asistido por Computador , Microscopía Electrónica de Transmisión , Datos de Secuencia Molecular , Myxozoa/anatomía & histología , Myxozoa/genética , Enfermedades Parasitarias en Animales/epidemiología , Prevalencia , ARN Ribosómico 18S/genética , Ríos , Alineación de Secuencia , Esporas/ultraestructura , West Virginia/epidemiología
12.
Neuroscience ; 226: 1-9, 2012 Dec 13.
Artículo en Inglés | MEDLINE | ID: mdl-22986169

RESUMEN

Glycogen synthase kinase 3 (GSK3) is a serine/threonine kinase that has been implicated in psychiatric diseases, neurodevelopment, and circadian regulation. Both GSK3 isoforms, α and ß, exhibit a 24-h variation of inhibitory phosphorylation within the suprachiasmatic nucleus (SCN), the primary circadian pacemaker. We examined the hypothesis that rhythmic GSK3 activity is critical for robust circadian rhythmicity using GSK3α(21A/21A)/ß(9A/9A) knock-in mice with serine-alanine substitutions at the inhibitory phosphorylation sites, making both forms constitutively active. We monitored wheel-running locomotor activity of GSK3 knock-in mice and used loose-patch electrophysiology to examine the effect of chronic GSK3 activity on circadian behavior and SCN neuronal activity. Double transgenic GSK3α/ß knock-in mice exhibit disrupted behavioral rhythmicity, including significantly decreased rhythmic amplitude, lengthened active period, and increased activity bouts per day. This behavioral disruption was dependent on chronic activation of both GSK3 isoforms and was not seen in single transgenic GSK3α or GSK3ß knock-in mice. Underlying the behavioral changes, SCN neurons from double transgenic GSK3α/ß knock-in mice exhibited significantly higher spike rates during the subjective night compared to those from wild-type controls, with no differences detected during the subjective day. These results suggest that constitutive activation of GSK3 results in the loss of the typical day/night variation of SCN neuronal activity. Together, these results implicate GSK3 activity as a critical regulator of circadian behavior and neurophysiological rhythms. Because GSK3 has been implicated in numerous pathologies, understanding how GSK3 modulates circadian rhythms and neurophysiological activity may lead to novel therapeutics for pathological disorders and circadian rhythm dysfunction.


Asunto(s)
Potenciales de Acción/fisiología , Ritmo Circadiano/fisiología , Glucógeno Sintasa Quinasa 3/fisiología , Núcleo Supraquiasmático/fisiología , Animales , Animales Modificados Genéticamente , Western Blotting , Fenómenos Electrofisiológicos , Activación Enzimática/fisiología , Glucógeno Sintasa Quinasa 3/genética , Glucógeno Sintasa Quinasa 3/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Actividad Motora/fisiología , Neuronas/fisiología , Técnicas de Placa-Clamp , Fosforilación
13.
Environ Sci Technol ; 46(17): 9571-6, 2012 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-22834642

RESUMEN

Large-scale soil application of biochar may enhance soil fertility, increasing crop production for the growing human population, while also sequestering atmospheric carbon. But reaching these beneficial outcomes requires an understanding of the relationships among biochar's structure, stability, and contribution to soil fertility. Using quantitative (13)C nuclear magnetic resonance (NMR) spectroscopy, we show that Terra Preta soils (fertile anthropogenic dark earths in Amazonia that were enriched with char >800 years ago) consist predominantly of char residues composed of ~6 fused aromatic rings substituted by COO(-) groups that significantly increase the soils' cation-exchange capacity and thus the retention of plant nutrients. We also show that highly productive, grassland-derived soils in the U.S. (Mollisols) contain char (generated by presettlement fires) that is structurally comparable to char in the Terra Preta soils and much more abundant than previously thought (~40-50% of organic C). Our findings indicate that these oxidized char residues represent a particularly stable, abundant, and fertility-enhancing form of soil organic matter.


Asunto(s)
Carbón Orgánico/química , Suelo/química , Secuestro de Carbono , Espectroscopía de Resonancia Magnética
14.
Micron ; 40(1): 74-9, 2009 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-18378149

RESUMEN

The effect of the oxygen plasma treatment on the electronic states of multi-wall carbon nanotubes (MWCNTs) is analyzed by X-ray photoemission measurements (XPS) and UPS, both using synchrotron radiation. It is found that the plasma treatment effectively grafts oxygen at the CNT-surface. Thereafter, the interaction between evaporated Pd and pristine or oxygen plasma-treated MWCNTs is investigated. Pd is found to nucleate at defective sites, whether initially present or introduced by oxygen plasma treatment. The plasma treatment induced a uniform dispersion of Pd clusters at the CNT-surface. The absence of additional features in the Pd 3d and C 1s core levels spectra testifies that no Pd-C bond is formed. The shift of the Pd 3d core level towards high-binding energy for the smallest clusters is attributed to the Coulomb energy of the charged final state.

15.
Aesthetic Plast Surg ; 32(5): 743-7, 2008 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-18446403

RESUMEN

BACKGROUND: Well-documented evidence shows that estrogen increases the risk of deep vein thrombosis (DVT), and that the effects of DVT are compounded by the stress of surgery and an anesthetic. METHODS: This study sought to determine the current views and practice of plastic surgeons regarding combined oral contraceptive and surgery. In the United Kingdom, 285 consultant plastic surgeons were identified, and postal questionnaires were distributed to each surgeon. RESULTS: Of 286 postal questionnaires distributed to consultant plastic surgeons, 53% were returned and analyzed. Most of the surgeons considered combined oral contraceptive and surgery to be a risk factor for DVT, although only 54% discontinued it before surgery. Approximately 50% believed hormone-replacement therapy (HRT) is a risk, but fewer than a one-fourth of surgeons stopped its use before surgery. There was a range of distribution for the length of time HRT was discontinued for surgery. The majority of consultants discontinue HRT use for 5 to 6 weeks before surgery and until full ambulation after surgery. Data retrieved were used to compare documented evidence relating to combined oral contraceptive and surgery and its association with DVT. CONCLUSION: This survey shows that the management of patients taking estrogen-containing medication before plastic surgery varies, and guidelines regarding this should be sought.


Asunto(s)
Anticonceptivos Orales Combinados/efectos adversos , Terapia de Reemplazo de Estrógeno/efectos adversos , Cirugía Plástica/métodos , Tromboembolia/prevención & control , Trombosis de la Vena/prevención & control , Adulto , Actitud del Personal de Salud , Anticonceptivos Orales Combinados/administración & dosificación , Terapia de Reemplazo de Estrógeno/métodos , Femenino , Estudios de Seguimiento , Encuestas de Atención de la Salud , Humanos , Persona de Mediana Edad , Pautas de la Práctica en Medicina/normas , Pautas de la Práctica en Medicina/tendencias , Cuidados Preoperatorios , Prevención Primaria/métodos , Derivación y Consulta/estadística & datos numéricos , Medición de Riesgo , Sensibilidad y Especificidad , Encuestas y Cuestionarios , Tromboembolia/inducido químicamente , Resultado del Tratamiento , Reino Unido , Trombosis de la Vena/inducido químicamente
16.
Anat Embryol (Berl) ; 208(1): 7-18, 2004 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-15007643

RESUMEN

Limb buds develop from lateral plate-derived stationary mesenchyme and are invaded by cells from extrinsic regions. The largest populations of these cells are myogenic precursor cells that originate from the lateral dermomyotomes. After detachment under the influence of SF/HGF, myogenic precursor cells migrate in a proximo-distal direction and populate a dorsal and ventral zone. The patterning mechanism leading to the segregation of dorsal and ventral myogenic cells is at present not understood. Lmx1b, a LIM homeodomain transcription factor expressed in the dorsal mesenchyme of the developing limb bud, forms a sharp dorso-ventral boundary of expression within the limb. We have investigated the mechanisms of dorso-ventral patterning of muscle precursor cells in the limb buds with respect to Lmx1b expression using quail-chick chimeras and transgenic mice. Although cells appeared to be capable of migrating either ventrally or dorsally, their migration was restricted to the position they had attained during normal development or in the experimental situation. They were never found to cross the dorso-ventral boundary. Immunohistochemistry and histological analysis of mice carrying a LacZ reporter gene under the control of the endogenous Lmx1b locus confirmed that myogenic precursors in the limb bud were devoid of Lmx1b expression. In addition, it was shown that Lmx1b is not only expressed at early stages of limb development but maintains its pattern, at least until after birth. The present study provides new insights into migratory pathways of myogenic precursor cells and reveals details of Lmx1b expression on a cellular basis within the limb.


Asunto(s)
Extremidades/embriología , Proteínas de Homeodominio/metabolismo , Músculo Esquelético/embriología , Células Madre/fisiología , Animales , Movimiento Celular , Embrión de Pollo , Quimera , Coturnix , Embrión de Mamíferos/metabolismo , Embrión de Mamíferos/fisiología , Embrión no Mamífero/metabolismo , Embrión no Mamífero/fisiología , Desarrollo Embrionario y Fetal , Proteínas con Homeodominio LIM , Mesodermo/trasplante , Ratones , Ratones Transgénicos , Células Madre/metabolismo , Distribución Tisular , Factores de Transcripción
17.
Clin Physiol Funct Imaging ; 24(1): 46-57, 2004 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-14717748

RESUMEN

A method to estimate pulmonary diffusing capacity for O(2) (D(LO2)) during exercise based on routine O(2) and CO(2) transport variables is presented. It is based on the fitting of a mathematical model to gas exchange data. The model includes heterogeneity (described as two exchanging compartments), diffusion limitation and right-to-left shunt. Mass conservation equations and Bohr integration were solved to calculate partial pressures in each compartment. Diffusion was distributed with perfusion. Two-compartment ventilation and perfusion distributions were estimated at rest during conditions of negligible diffusion limitation. These distributions were used during hypoxic and normoxic exercise to obtain the D(LO2) from the model computations (D(LO2)2C) compatible with experimental data. Three normals, four sarcoid patients and four patients after lung resection were studied. An independent technique for carbon monoxide was used to provide experimental estimates of DLo2 (D(LO2)EXP, rebreathing technique for sarcoid patients and single breath for lung resection). D(LO2)2C was highly correlated with D(LO2)EXP (r2 = 0.95, P<0.001) and the slope of the regression line was not statistically different from 1. The mean (D(LO2)EXP - D(LO2)2C) difference was -1.0 +/- 7.4 ml min-1 mmHg-1. The results suggest that use of a refined analytical procedure allows for assessment of D(LO2) from routine O(2) and CO(2) measurements comparable with those obtained from independent carbon monoxide techniques. The method may be an alternative for estimates of D(LO2) during exercise.


Asunto(s)
Algoritmos , Dióxido de Carbono/metabolismo , Diagnóstico por Computador/métodos , Modelos Biológicos , Consumo de Oxígeno , Oxígeno/metabolismo , Intercambio Gaseoso Pulmonar , Sarcoidosis Pulmonar/fisiopatología , Adulto , Simulación por Computador , Difusión , Prueba de Esfuerzo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Sarcoidosis Pulmonar/diagnóstico , Sensibilidad y Especificidad
18.
J Contam Hydrol ; 67(1-4): 113-32, 2003 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-14607473

RESUMEN

A field experiment was conducted at Canadian Forces Base Borden (CFB Borden) to assess the air distribution from a single in situ air sparging injection point. This aquifer consists of fine to medium sand deposited in horizontal layers. The permeability at the study location varied from 10(-10) to 10(-14) m2 and distinct low permeability horizons were present at approximately 1.2, 2.0, and 2.9 m below the water table. Prior to air injection, a 15x15-m portion of the vadose zone was excavated to the water table (approximately 1 m below ground surface) in order to visually observe air release distribution at the water table. The water table was actively maintained 5 cm above the excavated surface. The sparging system operated for a period of 7 days with an injection flow rate of 200 m3/days (5 scfm). The resulting subsurface air distribution was assessed using a variety of techniques including neutron logging, borehole and surface ground penetrating radar, piezometric head measurements, surface visualization, and hydraulic testing. Through this combination of tests, it was demonstrated that variations in permeability and, hence, capillary pressure at the site were sufficient to cause the injected air to spread laterally, forming stratigraphically trapped air pockets beneath the low permeability horizons. The formation of these air pockets eventually resulted in a buildup of capillary pressure that exceeded the air entry pressure and allowed some air to migrate up through the lower permeability layers. Each of the assessment techniques employed generated information at different spatial scales that prevented a direct comparison of the results from the various techniques; however, the results from all techniques proved to be critical in the interpretation of the experimental data. As a consequence, the different assessment techniques should not be viewed as alternatives, but rather as complimentary techniques.


Asunto(s)
Suelo , Abastecimiento de Agua , Aire , Movimientos del Aire , Monitoreo del Ambiente , Contaminación Ambiental/prevención & control , Permeabilidad , Presión , Volatilización , Movimientos del Agua
19.
Peptides ; 24(2): 313-9, 2003 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-12668218

RESUMEN

In the present experimental paradigm, we examine the effect of L-prolyl-L-leucyl-glycinamide (PLG) co-administration with haloperidol on vacuous chewing movements (VCM) in rats-a model of tardive dyskinesia (TD) in humans. We examined the dose dependent induction of VCM through both injected and orally administered PLG (MIF-1). Our results show significant levels of VCM attenuation (P<0.05) in rats treated with 10mg/kg of PLG. Doses of 1 and 100mg/kg were ineffective. Reductions were present in both orally treated and injected rats. We also examined the therapeutic effect of a peptidomimetic of PLG-PAOPA. PAOPA was able to produce similar behavioral effects to PLG at a dose, which was 100-fold lower than the effective dose of PLG. These results suggest that PLG may play a role in D2 receptor expression and function, as well as providing a therapy for neuroleptic induced TD.


Asunto(s)
Hormona Inhibidora de la Liberación de MSH/farmacología , Masticación/efectos de los fármacos , Pirrolidinonas/farmacología , Administración Oral , Animales , Conducta Animal/efectos de los fármacos , Modelos Animales de Enfermedad , Relación Dosis-Respuesta a Droga , Discinesia Inducida por Medicamentos/tratamiento farmacológico , Haloperidol/administración & dosificación , Haloperidol/antagonistas & inhibidores , Humanos , Inyecciones , Masculino , Ratas , Ratas Sprague-Dawley , Factores de Tiempo
20.
J Environ Qual ; 32(2): 583-90, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-12708682

RESUMEN

Some soils develop severe and persistent water repellency following contamination with crude oil. This study was conducted to characterize and compare the spatial distribution of soil water repellency and residual oil contamination at 12 such sites. The molarity of ethanol droplet (MED) test was used to assess soil water repellency and the content of dichloromethane-extractable organics (DEO) was used to quantify residual oil in soil. We found a relatively strong positive correlation between MED and DEO in soil (r2 = 0.74). Both variables tended to decrease abruptly with depth at 11 of the 12 study sites. Dichloromethane-extractable organics similarly decreased with depth in control adjacent soil (MED = 0 M), but from an average concentration one to two orders of magnitude lower than in water-repellent soil. Using data from corresponding control adjacent and water-repellent soils, we determined that approximately 29 and 10% of measured total organic carbon in water-repellent A- and B-horizon soil, respectively, consists of dichloromethane-insoluble organic carbon of petroleum origin. We propose that this fraction contains most of the causative agents of soil water repellency at the studied sites.


Asunto(s)
Carbono/química , Petróleo , Contaminantes del Suelo/análisis , Solubilidad , Agua
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