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1.
Biophys J ; 123(4): 502-508, 2024 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-38243596

RESUMEN

Cell dimensions of rod-shaped bacteria such as Escherichia coli are connected to mass growth and chromosome replication. During their interdivision cycle (τ min), cells enlarge by elongation only, but at faster growth in richer media, they are also wider. Changes in width W upon nutritional shift-up (shortening τ) occur during the division process. The elusive signal directing the mechanism for W determination is likely related to the tightly linked duplications of the nucleoid (DNA) and the sacculus (peptidoglycan), the only two structures (macromolecules) existing in a single copy that are coupled, temporally and spatially. Six known parameters related to the nucleoid structure and replication are reasonable candidates to convey such a signal, all simple functions of the key number of replication positions n(=C/τ), the ratio between the rates of growth (τ-1) and of replication (C-1). The current analysis of available literature-recorded data discovered that, of these, nucleoid complexity NC[=(2n-1)/(n×ln2)] is by far the most likely parameter affecting cell width W. The exceedingly high correlations found between these two seemingly unrelated measures (NC and W) indicate that coupling between them is of major importance to the species' survival. As an exciting corollary, to the best of our knowledge, a new, indirect approach to estimate DNA replication rate is revealed. Potential involvement of DNA topoisomerases in W determination is also proposed and discussed.


Asunto(s)
Proteínas de Escherichia coli , Escherichia coli , División Celular , Replicación del ADN , Proteínas de Escherichia coli/metabolismo , Bacterias/genética , Cromosomas Bacterianos/metabolismo , Proteínas Bacterianas/metabolismo
2.
Headache ; 60(10): 2389-2405, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32997813

RESUMEN

OBJECTIVE: In this experimental study, we aimed to determine whether guided music listening (GML) - a music intervention based on models of mood mediation and attention modulation - modulates masticatory muscle activity and awake bruxism in subjects with chronic painful muscular temporomandibular disorders (TMD myalgia, mTMD), a condition causing a significant burden to patients, their families, and healthcare systems. BACKGROUND: Awake bruxism - a stress behavior characterized by clenching of the teeth - is a strong contributor to chronic mTMD. GML modulates psychological stress and motor responses and could thus reduce muscle activity in chronic musculoskeletal conditions, including mTMD. METHODS: We recorded the electromyographic (EMG) activity in the right masseter of 14 women with chronic (>6 months) mTMD (median [IQR] = 39.5.3 [24.3] years) and 15 pain-free women (median [IQR] = 30.0 [3.5] years) during a GML session, including 3 music (stressful, relaxing, and participants' favorite music) and a no-music (pink noise) control blocks, each lasting 15 minutes. We measured the motor effort of the right masseter relative to the participants' maximum voluntary contraction (MVC), the muscular effort to maintain mandibular posture (EMGposture ), and to produce spontaneous awake bruxism episodes (EMGbruxism ), and the duration and frequency of spontaneous awake bruxism episodes. We tested between-group and within-group (between blocks) differences, as well as the effect of the interaction group by experimental block on these outcome measures. RESULTS: In both groups, EMGposture was significantly affected by the interaction group by experimental block (P < .001). Compared to pink noise [mean (95% CI); mTMD: 2.2 (1.6-2.8) %MVC; Controls: 1.1 (0.5-1.7) %MVC], EMGposture increased during the stressful music block [contrast estimate (95% CI); mTMD: +0.8 (0.7-0.8) %MVC; Controls: +0.3 (0.3-0.4) %MVC; both P < .001], and decreased during the relaxing [mTMD: -0.4 (-0.5 to -0.4) %MVC; Controls: -0.3 (-0.4 to -0.3) %MVC; both P < .001] and favorite [mTMD: -0.5 (-0.6 to -0.5) %MVC; Controls: -0.5 (-0.5 to -0.4) %MVC; both P < .001] music blocks. EMGposture was greater in mTMD individuals than controls during the favorite music [contrast estimate (95% CI): +1.1 (0.2-1.9) %MVC; P = .019] and the pink noise [+1.1 (0.2-2.0) %MVC; P = .014] blocks. EMGbruxism was significantly affected by the interaction group by experimental block (P < .001). In mTMD participants, compared to the pink noise block [mean (95% CI); 23.8 (16.0-31.6) %MVC], EMGbruxism increased during the stressful music block [contrast estimate (95% CI); +10.2 (8.6-11.8) %MVC], and decreased during the relaxing [-6.2 (-8.1 to -4.3) %MVC; P < .001] and favorite [-10.2 (-12.2 to -9.1) %MVC; P < .001] music blocks. These effects were not observed in the control group [mean (95% CI); pink noise: 19.3 (10.9-27.6); stressful: 21.2 (12.9-29.4) %MVC; relaxing: 21.6 (13.3-29.9) %MVC; favorite: 24.2 (15.8-32.7) %MVC; all P > .05]. EMGbruxism was significantly greater in mTMD participants than controls during the stressful music block [contrast estimate (95% CI): +12.9 (1.6-24.2) %MVC; P = .026). GML did not affect the duration or the frequency of awake bruxism in either group (median [IQR], mTMD: 23.5 [96.7] s, range 1-1300 seconds; Controls: 5.5 [22.5], range 0-246 seconds; P = .108). The frequency of awake bruxism episodes was greater in the mTMD group compared to controls only during the pink noise block (median [IQR], mTMD: 5 [15.3] episodes, range 0-62 episodes; Controls: 1 [3] episode, range 0-27 episodes; P = .046). No significant between-group differences were found in either the overall time spent engaging in awake bruxism (median [IQR], mTMD: 23.5 [96.7] s, range 1-1300 seconds; Controls: 5.5 [22.5], range 0-246 seconds; P = .108), or during each block (all P > .05). CONCLUSIONS: In subjects with chronic mTMD, relaxing music and the individual's favorite music decreased the muscular effort during spontaneous awake bruxism episodes by 26% and 44% (relative changes), respectively. In contrast, stressful music increases it by about 43%. Because of its positive effects on awake bruxism, GML with selected music could be a promising and non-invasive component of a multimodal approach for the management of chronic mTMD.


Asunto(s)
Bruxismo , Dolor Crónico , Musicoterapia , Música , Mialgia , Trastornos de la Articulación Temporomandibular , Adulto , Bruxismo/complicaciones , Bruxismo/fisiopatología , Bruxismo/psicología , Bruxismo/terapia , Dolor Crónico/etiología , Dolor Crónico/fisiopatología , Dolor Crónico/psicología , Dolor Crónico/terapia , Electromiografía , Femenino , Humanos , Músculo Masetero/fisiopatología , Persona de Mediana Edad , Mialgia/etiología , Mialgia/fisiopatología , Mialgia/psicología , Mialgia/terapia , Trastornos de la Articulación Temporomandibular/fisiopatología , Trastornos de la Articulación Temporomandibular/psicología , Trastornos de la Articulación Temporomandibular/terapia
3.
Neurosurg Focus ; 45(4): E2, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-30269595

RESUMEN

There is inadequate pediatric neurosurgical training to meet the growing burden of disease in low- and middle-income countries (LMIC). Subspecialty expertise in the management of hydrocephalus and spina bifida-two of the most common pediatric neurosurgical conditions-offers a high-yield opportunity to mitigate morbidity and avoid unnecessary death. The CURE Hydrocephalus and Spina Bifida (CHSB) fellowship offers an intensive subspecialty training program designed to equip surgeons from LMIC with the state-of-the-art surgical skills and equipment to most effectively manage common neurosurgical conditions of childhood. Prospective fellows and their home institution undergo a comprehensive evaluation before being accepted for the 8-week training period held at CURE Children's Hospital of Uganda (CCHU) in Mbale, Uganda. The fellowship combines anatomy review, treatment paradigms, a flexible endoscopic simulation lab, daily ward and ICU rounds, radiology rounds, and clinic exposure. The cornerstone of the fellowship is the unique operative experience that includes a high volume of endoscopic third ventriculostomy with choroid plexus cauterization, myelomeningocele closure, and ventriculoperitoneal shunting, among many other procedures performed at CCHU. Upon completion, fellows return to their home institution to establish or rejuvenate a robust pediatric practice as part of a worldwide network of CHSB trainees committed to the care of underserved children. To date, the fellowship has graduated 33 surgeons from 20 different LMIC who are independently performing thousands of hydrocephalus and spina bifida operations each year.


Asunto(s)
Becas , Hidrocefalia/cirugía , Neurocirugia/educación , Pediatría/educación , Disrafia Espinal/cirugía , Plexo Coroideo/cirugía , Países en Desarrollo , Becas/métodos , Recursos en Salud , Humanos , Modelos Educacionales , Tercer Ventrículo/cirugía , Uganda , Ventriculostomía/métodos
5.
J Intensive Care Med ; 30(6): 351-7, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24509493

RESUMEN

BACKGROUND: Interhospital transportation of critically ill patients is challenging. The risk incurred by the patient is compounded when stabilization and application of appropriate therapies are delayed. The purpose of this study was to first develop an interhospital intensive care unit (ICU) transfer instrument to systematize communication and determine feasibility of use. Then, the transfer instrument was tested for effects on patient mortality, stability on arrival, and recommended therapy implementation. METHOD: The instrument was developed and pilot tested for 6 months to optimize function and applicability. Then, a before-and-after quasi-experimental study tested this instrument by assessing several key outcomes. Outcomes measured included 48-hour mortality, ICU mortality, hospital mortality, emergent intubation, emergent central venous catheter insertion, immediate change in antibiotics, and addition of vasopressors immediately on arrival. Patients were compared by age, gender, cause for admission, and Acute Physiology and Chronic Health Evaluation (APACHE) II score. A standardized mortality ratio was calculated using the patient's APACHE II score. Pretransport recommendations to referring physicians and adherence to recommendations were also measured. RESULTS: The preintervention group consisted of 134 patients collected continuously over 6 months. The postintervention group was collected continuously over a 6-month period and included 77 patients. The interhospital ICU transfer instrument was associated with fewer emergent central venous catheter insertions and fewer changes in antibiotics on arrival. Recommendations to transferring physicians were followed 90% of the time. CONCLUSIONS: The interhospital ICU transfer instrument is a tool that is effective in coordinating the transfer of medical ICU patients. Implementation leads to timely critical interventions and may reduce mortality.


Asunto(s)
Cuidados Críticos/normas , Servicios Médicos de Urgencia/estadística & datos numéricos , Unidades de Cuidados Intensivos/normas , Transferencia de Pacientes/normas , APACHE , Adulto , Anciano , Cuidados Críticos/métodos , Cuidados Críticos/estadística & datos numéricos , Enfermedad Crítica/mortalidad , Servicios Médicos de Urgencia/normas , Estudios de Factibilidad , Femenino , Mortalidad Hospitalaria , Humanos , Unidades de Cuidados Intensivos/estadística & datos numéricos , Tiempo de Internación , Masculino , Persona de Mediana Edad , Ensayos Clínicos Controlados no Aleatorios como Asunto , Evaluación de Resultado en la Atención de Salud , Transferencia de Pacientes/estadística & datos numéricos , Proyectos Piloto
6.
Biol Lett ; 9(5): 20130144, 2013 Oct 23.
Artículo en Inglés | MEDLINE | ID: mdl-23925831

RESUMEN

The outer armour of fossil jawless fishes (Heterostraci) is, predominantly, a bone with a superficial ornament of dentine tubercles surrounded by pores leading to flask-shaped crypts (ampullae). However, despite the extensive bone present in these early dermal skeletons, damage was repaired almost exclusively with dentine. Consolidation of bone, by dentine invading and filling the vascular spaces, was previously recognized in Psammolepis and other heterostracans but was associated with ageing and dermal shield wear (reparative). Here, we describe wound repair by deposition of dentine directly onto a bony scaffold of fragmented bone. An extensive wound response occurred from massive deposition of dentine (reactionary), traced from tubercle pulp cavities and surrounding ampullae. These structures may provide the cells to make reparative and reactionary dentine, as in mammalian teeth today in response to stimuli (functional wear or damage). We suggest in Psammolepis, repair involved mobilization of these cells in response to a local stimulatory mechanism, for example, predator damage. By comparison, almost no new bone is detected in repair of the Psammolepis shield. Dentine infilling bone vascular tissue spaces of both abraded dentine and wounded bone suggests that recruitment of this process has been evolutionarily conserved over 380 Myr and precedes osteogenic skeletal repair.


Asunto(s)
Desarrollo Óseo , Dentina/metabolismo , Peces/fisiología , Fósiles , Heridas y Lesiones/metabolismo , Animales
8.
PLoS One ; 17(5): e0268191, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35522625

RESUMEN

Assessing levels of aggression-specifically reactive violence-has been a challenge in the past, since individuals might be reluctant to self-report aggressive tendencies. Furthermore, experimental studies often lack ecological validity. Immersive Virtual Reality (IVR) offers a reliable, ethically safe environment, and is the most realistic virtual simulation method currently available. It allows researchers to test participants' aggressive responses to realistic provocations from virtual humans. In the current study, 116 participants completed our IVR aggression task, in which they encountered avatars who would either approach them in a friendly or provocative fashion. Participants had the option either to shake hands or hit the virtual human, in congruent and incongruent trials. In congruent trials, the response required of the participant matched the approach with the avatar (e.g., hitting the avatar after provocation). In incongruent trials there was a mismatch between the avatars approach and the participants required response. Congruent trials were designed to measure the immediate reaction towards the virtual human, and incongruent trials to assess response inhibition. Additionally, participants also completed traditional questionnaire-based measures of aggression, as well as reporting their past violent behaviour. We found that the immediate aggressive responses in the IVR task correlated with the established questionnaire measures (convergent validity), and we found that the IVR task was a stronger predictor of past violent behaviour than traditional measures (discriminant validity). This suggests that IVR might be an effective way to assess aggressive behaviour in a more indirect, but realistic manner, than current questionnaire assessment.


Asunto(s)
Realidad Virtual , Simulación por Computador , Humanos , Encuestas y Cuestionarios , Violencia
9.
Epilepsia ; 50(5): 1256-61, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-19175392

RESUMEN

Epilepsy prevalence in the developing world is many fold that found in developed countries. For individuals whose conditions failed to respond to pharmacotherapy, surgery is the only opportunity for cure. In Uganda, we developed a center for treatment of intractable temporal lobe epilepsy (iTLE) that functions within the technologic and expertise constraints of a severely low resource area. Our model relies on partnership with epilepsy professionals and training of local staff. Patients were prescreened at regional clinics for iTLE. Individuals meeting inclusion criteria were referred to the treating Ugandan hospital (CURE Children's' Hospital of Uganda, CCHU) for video-EEG (electroencephalography), computed tomography (CT) imaging, and neuropsychological evaluation. Data were transferred to epilepsy experts for analysis and treatment recommendations. Ten patients were diagnosed with iTLE and surgically treated at CCHU. Six (60%) were seizure free, and there was no neurologic morbidity or mortality. Our model for surgical treatment of pharmacoresistant TLE has functioned successfully in a true developing world low resource setting.


Asunto(s)
Epilepsia del Lóbulo Temporal/cirugía , Procedimientos Neuroquirúrgicos/métodos , Adolescente , Electroencefalografía/métodos , Epilepsia del Lóbulo Temporal/diagnóstico , Epilepsia del Lóbulo Temporal/epidemiología , Femenino , Humanos , Masculino , Pruebas Neuropsicológicas , Proyectos Piloto , Tomografía Computarizada por Rayos X , Uganda/epidemiología , Adulto Joven
11.
Proc (Bayl Univ Med Cent) ; 31(1): 6-8, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29686543

RESUMEN

Out-of-hospital cardiac arrest (OHCA) is a major cause of mortality that is responsible for over 300,000 deaths in the United States each year. Underlying cardiac etiologies remain the most common culprit. Despite medical advances in the treatment of coronary artery disease, the mortality following OHCA remains dismal. Additionally, of those who survive the initial event, many are left with debilitating and irreversible anoxic brain injuries. Therefore, improving survival as well as neurologic outcome is of primary importance in this group. Our goal was to evaluate the underlying etiologies, neurologic outcomes, and cardiac interventions being performed in patients with OHCA presenting to our large tertiary care center. We retrospectively reviewed 181 charts of patients presenting to our emergency department over a 1-year time period with a diagnosis of OHCA. Following exclusion criteria, 130 patients remained, with 17 of those surviving to hospital admission. Of the 17 initial survivors, only 9 survived to hospital discharge and only 6 of those obtained good neurologic outcomes. Additionally, there was no mortality benefit in the 4 patients who had coronary angiography or percutaneous intervention.

12.
Proc (Bayl Univ Med Cent) ; 30(3): 301-302, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28670063

RESUMEN

We describe a man with the Marfan syndrome and a prior ascending aortic aneurysm resection who presented with knee pain and concern of endocarditis. Transesophageal echocardiogram showed no vegetations, and computed tomography angiogram of the heart showed a possible pseudoaneurysm. Cardiac catheterization and aortogram revealed the diagnosis of an aorto-right atrial fistula, which was then operatively repaired. This case highlights the role that cardiac catheterization with aortogram can play in the detection of aorto-atrial fistula.

13.
PLoS One ; 12(1): e0170133, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28076403

RESUMEN

[This corrects the article DOI: 10.1371/journal.pone.0164374.].

15.
PLoS One ; 11(10): e0164374, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27723826

RESUMEN

The nature of moral action versus moral judgment has been extensively debated in numerous disciplines. We introduce Virtual Reality (VR) moral paradigms examining the action individuals take in a high emotionally arousing, direct action-focused, moral scenario. In two studies involving qualitatively different populations, we found a greater endorsement of utilitarian responses-killing one in order to save many others-when action was required in moral virtual dilemmas compared to their judgment counterparts. Heart rate in virtual moral dilemmas was significantly increased when compared to both judgment counterparts and control virtual tasks. Our research suggests that moral action may be viewed as an independent construct to moral judgment, with VR methods delivering new prospects for investigating and assessing moral behaviour.


Asunto(s)
Nivel de Alerta/fisiología , Frecuencia Cardíaca/fisiología , Juicio/fisiología , Obligaciones Morales , Adulto , Femenino , Humanos , Masculino , Interfaz Usuario-Computador
16.
Aerosp Med Hum Perform ; 86(5): 497-500, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25945677

RESUMEN

Howard CT, Vu P. You're the flight surgeon: hand, foot, and mouth disease. Aerosp Med Hum Perform. 2015; 86(5):497-500.


Asunto(s)
Enfermedad de Boca, Mano y Pie/diagnóstico , Adulto , Medicina Aeroespacial , Diagnóstico Diferencial , Enfermedad de Boca, Mano y Pie/fisiopatología , Enfermedad de Boca, Mano y Pie/prevención & control , Humanos , Masculino , Personal Militar
18.
FEBS Lett ; 531(3): 505-8, 2002 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-12435601

RESUMEN

Type X collagen expression is restricted to hypertrophic chondrocytes in the endochondral growth plate. Transient transfection of reporter constructs containing the human collagen X promoter into primary growth plate chondrocytes identified a cis-acting positive regulatory DNA element(s) that has cell-specific enhancer properties and binds a nuclear protein expressed specifically in growth plate chondrocytes. Functional disruption of this region results in a significant reduction in the activation of reporter gene transcription. The identified enhancer is a major element controlling both high-level and cell-specific expression of type X collagen gene.


Asunto(s)
Colágeno Tipo X/genética , Elementos de Facilitación Genéticos , Regulación de la Expresión Génica/genética , Secuencia de Bases , Células Cultivadas , Cloranfenicol O-Acetiltransferasa/genética , Condrocitos/metabolismo , ADN , Humanos , Regiones Promotoras Genéticas
19.
Am J Primatol ; 15(2): 171-180, 1988.
Artículo en Inglés | MEDLINE | ID: mdl-31968898

RESUMEN

The effects of physical and chemical restraint on glucose clearance and insulin secretion were evaluated during intravenous glucose tolerance testing in Macaca nigra. Conscious monkeys placed in plexiglas cylindrical restraining devices (CRD) appeared relaxed, but glucose clearance and insulin secretion were impaired. A combination of midazolam with ketamine, compared to ketamine alone, did not cause detectable changes in the intravenous glucose tolerance tests; midazolam also reduced adverse reactions to ketamine and extended the duration of anesthesia. The cylindrical restraining device can be convenient for examining monkeys, but it is limited by its adverse affects on metabolic and hormonal measurements in intravenous glucose-tolerance tests. Chemical restraint using ketamine with midazolam was more effective than ketamine alone.

20.
Am J Primatol ; 11(2): 147-162, 1986.
Artículo en Inglés | MEDLINE | ID: mdl-31979457

RESUMEN

Rhesus macaques (Macaca mulatta) from Cayo Santiago were examined for evidence of carbohydrate intolerance indicative of potential development of non-insulin-dependent diabetes mellitus (NIDDM). Monkeys 6 to >20 years from natal Groups J, M, and P, an AGED Group (all >20 years), and unrelated monkeys removed from the island in association with other groups (CAYO), were examined with intravenous glucose tolerance tests (iv-GTT). Morphometric measurements were made on all tested monkeys. Impairments included fasting hyperglycemia (>115 mg/dl), impaired glucose clearance (K <2.0%/min), fasting hyperinsulinemia (>150 µU/ml) or hypoinsulinemia (<20 µU/ml), and insulin secretory abnormalities (>500 µU/ml or <75 µU/ml). Natal groups J and M had 31% with impairments, group P had 0% the AGED group had 45%, and the CAYO group had 33%. Impaired glucose clearance was usually attributable to a reduced insulin response. Impairments correlated significantly (p ⩽ 0.05) to body weight and a modified Quetelet index, but not to sex, acute stress, or islet cell antibodies; the relationships to age could not be delineated in this survey. Impairements in monkeys are indicative of various stages in the asynchronous development of carbohydrate intolerance leading to NIDDM.

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