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1.
CBE Life Sci Educ ; 20(4): ar54, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34546099

RESUMEN

Evidence-based teaching practices (EBPs) foster college science, technology, engineering, and mathematics (STEM) students' engagement and performance, yet our knowledge of what contributes to the effectiveness of these practices is less established. We propose a framework that links four social-cognitive variables-students' trust in their instructors, growth mindset, buy-in to instructional practices, and course engagement-to long-standing desired student outcomes of academic performance and intent to persist in science. This framework was tested in classrooms identified as having a high level of EBP implementation with a multi-institutional sample of 2102 undergraduates taught by 14 faculty members. Results indicate that the buy-in framework is a valid representation of college students' learning experiences within EBP contexts overall as well as across underrepresented student groups. In comparison to students' level of growth mindset, students' trust in their instructors was more than twice as predictive of buy-in to how the course was being taught, suggesting that students' views of their instructors are more associated with thriving in a high-EBP course environment than their views of intelligence. This study contributes to the dialogue on transforming undergraduate STEM education by providing a validated student buy-in framework as a lens to understand how EBPs enhance student outcomes.


Asunto(s)
Estudiantes , Confianza , Ingeniería , Humanos , Matemática , Enseñanza , Tecnología
2.
Adv Physiol Educ ; 45(4): 803-809, 2021 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-34581619

RESUMEN

This article captures a collective reflection on the successes and challenges we experienced when teaching physiology laboratories online during the COVID-19 pandemic. Physiology instructors from six institutions discussed their own efforts to redesign meaningful physiology laboratories that could be taught remotely, as the nation scrambled to respond to the sudden shift out of the classroom. Despite the complexity of this task, clear themes emerged as our courses transitioned to an online format in spring 2020 and were solidified in the fall of 2020. This article reflects on the history, features, benefits, and challenges of current laboratory teaching when applying a scientific teaching approach to facilitate the redesign process. We believe online networks like ours can facilitate information sharing, promote innovations, and provide support for instructors. The insights we gained through this collaboration will influence our thinking about the future of the physiology lab, whether online or in person.


Asunto(s)
COVID-19 , Educación a Distancia , Humanos , Pandemias , SARS-CoV-2 , Estudiantes
3.
CBE Life Sci Educ ; 20(2): es5, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33885327

RESUMEN

Student-centered teaching practices such as active learning continue to gain momentum in college science education. Many instructors committed to these innovative practices transform their classrooms beyond the standard lecture. Nevertheless, widespread implementation of these practices is limited, because the learning benefits for students are often attained through increased instructional complexity to which many instructors cannot commit. When co-instructors are teaching the course, the level of commitment to building a student-centered classroom may be even more profound. For these reasons, new tools are needed to help instructors and co-instructors plan, organize, evaluate, and communicate their classroom innovations. Pathway modeling is a tool with the potential to fill this gap. Unlike curriculum mapping-which identifies academic content gaps, redundancies, and misalignments by examining a series of courses within a plan of study-course pathway modeling creates a visual map of a single course and reveals how teaching practices influence short-, mid-, and long-term student learning outcomes. This essay demonstrates how course pathway modeling can help co-instructors better represent the complexity of student-centered teaching practices. We include guides for creating course pathway models and discuss how this approach offers the potential to improve curricular design, course evaluation, student assessment, and communication between co-instructors.


Asunto(s)
Estudiantes , Universidades , Curriculum , Humanos , Aprendizaje Basado en Problemas , Enseñanza
4.
Artículo en Inglés | MEDLINE | ID: mdl-32742547

RESUMEN

The Summer Institutes on Scientific Teaching (SI) is a faculty development workshop in which science, technology, engineering, and mathematics (STEM) instructors, particularly from biology, are trained in the Scientific Teaching (ST) pedagogy. While participants have generally reported positive experiences, we aimed to assess how the SI affected participants' teaching practices. Building on a previously developed taxonomy of ST practices, we surveyed SI participants from the 2004-2014 SI classes regarding specific ST practices. Participants' self-reported use and implementation of ST practices increased immediately after SI attendance as well as over a longer time frame, suggesting that implementation persisted and even increased with time. However, instructors reported implementation gains for some practices more than others. The practices with the highest gains were engaging students in their own learning, using learning goals in course design, employing formative assessment, developing overarching course learning goals, representing science as a process, and facilitating group discussion activities. We propose that the ST practices showing the greatest gains may serve as beneficial focal points for professional development programs, while practices with smaller gains may require modified dissemination approaches or support structures.

5.
J Neurophysiol ; 124(3): 740-749, 2020 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-32727273

RESUMEN

All inhalation anesthetics used clinically including isoflurane can suppress breathing; since this unwanted side effect can persist during the postoperative period and complicate patient recovery, there is a need to better understand how isoflurane affects cellular and molecular elements of respiratory control. Considering that astrocytes in a brainstem region known as the retrotrapezoid nucleus (RTN) contribute to the regulation of breathing in response to changes in CO2/H+ (i.e., function as respiratory chemoreceptors), and astrocytes in other brain regions are highly sensitive to isoflurane, we wanted to determine whether and how RTN astrocytes respond to isoflurane. We found that RTN astrocytes in slices from neonatal rat pups (7-12 days postnatal) respond to clinically relevant levels of isoflurane by inhibition of a CO2/H+-sensitive Kir4.1/5.1-like conductance [50% effective concentration (EC50) = 0.8 mM or ~1.7%]. We went on to confirm that similar levels of isoflurane (EC50 = 0.53 mM or 1.1%) inhibit recombinant Kir4.1/5.1 channels but not homomeric Kir4.1 channels expressed in HEK293 cells. We also found that exposure to CO2/H+ occluded subsequent effects of isoflurane on both native and recombinant Kir4.1/5.1 currents. These results identify Kir4.1/5.1 channels in astrocytes as novel targets of isoflurane. These results suggest astrocyte Kir4.1/5.1 channels contribute to certain aspects of general anesthesia including altered respiratory control.NEW & NOTEWORTHY An unwanted side effect of isoflurane anesthesia is suppression of breathing. Despite this clinical significance, effects of isoflurane on cellular and molecular elements of respiratory control are not well understood. Here, we show that isoflurane inhibits heteromeric Kir4.1/5.1 channels in a mammalian expression system and a Kir4.1/5.1-like conductance in astrocytes in a brainstem respiratory center. These results identify astrocyte Kir4.1/5.1 channels as novel targets of isoflurane and potential substrates for altered respiratory control during isoflurane anesthesia.


Asunto(s)
Anestésicos por Inhalación/farmacología , Astrocitos/efectos de los fármacos , Tronco Encefálico/efectos de los fármacos , Células Quimiorreceptoras/efectos de los fármacos , Isoflurano/farmacología , Canales de Potasio de Rectificación Interna/efectos de los fármacos , Fenómenos Fisiológicos Respiratorios/efectos de los fármacos , Animales , Animales Recién Nacidos , Modelos Animales de Enfermedad , Células HEK293 , Humanos , Ratas , Proteínas Recombinantes , Canal Kir5.1
6.
Elife ; 82019 04 26.
Artículo en Inglés | MEDLINE | ID: mdl-31025941

RESUMEN

Dravet syndrome (DS) is a form of epilepsy with a high incidence of sudden unexpected death in epilepsy (SUDEP). Respiratory failure is a leading cause of SUDEP, and DS patients' frequently exhibit disordered breathing. Despite this, mechanisms underlying respiratory dysfunction in DS are unknown. We found that mice expressing a DS-associated Scn1a missense mutation (A1783V) conditionally in inhibitory neurons (Slc32a1cre/+::Scn1aA1783V fl/+; defined as Scn1aΔE26) exhibit spontaneous seizures, die prematurely and present a respiratory phenotype including hypoventilation, apnea, and a diminished ventilatory response to CO2. At the cellular level in the retrotrapezoid nucleus (RTN), we found inhibitory neurons expressing the Scn1a A1783V variant are less excitable, whereas glutamatergic chemosensitive RTN neurons, which are a key source of the CO2/H+-dependent drive to breathe, are hyper-excitable in slices from Scn1aΔE26 mice. These results show loss of Scn1a function can disrupt respiratory control at the cellular and whole animal levels.


Asunto(s)
Epilepsias Mioclónicas/genética , Canal de Sodio Activado por Voltaje NAV1.1/genética , Respiración/genética , Convulsiones/genética , Potenciales de Acción/genética , Animales , Dióxido de Carbono/toxicidad , Modelos Animales de Enfermedad , Epilepsias Mioclónicas/fisiopatología , Humanos , Ratones , Mutación Missense/genética , Neuronas/metabolismo , Neuronas/patología , Convulsiones/fisiopatología , Muerte Súbita e Inesperada en la Epilepsia/patología
7.
CBE Life Sci Educ ; 17(1)2018.
Artículo en Inglés | MEDLINE | ID: mdl-29351911

RESUMEN

Graduate teaching assistants (GTAs) play important instructional roles in introductory science courses, yet they often have little training in pedagogy. The most common form of teaching professional development (PD) for GTAs is a presemester workshop held at the course, department, or college level. In this study, we compare the effectiveness of presemester workshops at three northeastern research universities, each of which incorporated scientific teaching as the pedagogical content framework. The comparison of GTA PD program outcomes at three different institutions is intended to test theoretical assertions about the key role of contextual factors in GTA PD efficacy. Pretest and posttest surveys were used to assess changes in GTA teaching self-efficacy and anxiety following the workshops, and an objective test was used to assess pedagogical knowledge. Analysis of pretest/posttest data revealed statistically significant gains in GTA teaching self-efficacy and pedagogical knowledge and reductions in teaching anxiety across sites. Changes in teaching anxiety and self-efficacy, but not pedagogical knowledge, differed by training program. Student ratings of GTAs at two sites showed that students had positive perceptions of GTAs in all teaching dimensions, and relatively small differences in student ratings of GTAs were observed between institutions. Divergent findings for some outcome variables suggest that program efficacy was influenced as hypothesized by contextual factors such as GTA teaching experience.


Asunto(s)
Educación de Postgrado , Evaluación de Programas y Proyectos de Salud , Enseñanza , Universidades , Femenino , Humanos , Conocimiento , Masculino , Autoeficacia , Estudiantes/estadística & datos numéricos , Encuestas y Cuestionarios , Adulto Joven
8.
CBE Life Sci Educ ; 17(1)2018.
Artículo en Inglés | MEDLINE | ID: mdl-29378750

RESUMEN

There is growing consensus regarding the effectiveness of active-learning pedagogies in college science courses. Less is known about ways that student-level factors contribute to positive outcomes in these contexts. The present study examines students' (N = 245) trust in the instructor-defined as perceptions of their instructor's understanding, acceptance, and care-and students' attitudes toward learning within an anatomy and physiology course featuring active learning. Analyses indicate that student trust of instructor and students' views of their own intelligence are both associated with student commitment to, and engagement in, active learning. Student-reported trust of the instructor corresponded to final grade, while students' views of their own intelligence did not. In an active-learning context in which students are more fully engaged in the learning process, student trust of the instructor was an important contributor to desired student outcomes.


Asunto(s)
Actitud , Curriculum , Aprendizaje Basado en Problemas , Ciencia/educación , Estudiantes , Confianza , Universidades , Femenino , Humanos , Masculino , Análisis Multivariante , Percepción , Análisis de Regresión
9.
J Thorac Dis ; 10(12): 6742-6752, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30746219

RESUMEN

BACKGROUND: The Chinese government has pay attention about tuberculosis infection among medical staff in infectious disease hospitals, but the effects have not yet been reported. This study will explore latent infection and immune function in the medical staff and systematically analyze the associated influencing factors. METHODS: Ninety-four medical staffs were enrolled and 20 medical staffs were defined as low risk group and others were high risk group. We used IFN-γ release assay and flow cytometry to analyze the latent TB infection status and immune function. Logistic regression analyses were performed to identify the independent risk factors of latent TB infection. RESULTS: This study explored and compared the infection status of medical workers and found that the rate of positive TB-IGRA results was higher among high risk group than in low risk group. Working environment, occupational history and work type were risk factors for TB infection in hospital. This study also found that high risk group had higher IFN-γ expression and a lower ratio of CD4+ to CD8+ T cells and further analysis found that this immune disorder is associated with wards and occupations. CONCLUSIONS: This study through rigorous sample collection and analysis found the risk factors of latent tuberculosis infection in health care workers. This finding may provide a theoretical basis to be used by the countries with a high TB burden to further improve their strategies for the prevention of TB infections in hospitals and may give an indication for improving the personal health of medical staff in infectious disease hospitals.

10.
J Clin Lab Anal ; 32(1)2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-28220979

RESUMEN

OBJECTIVE: Tuberculosis (TB)-interferon gamma release assay (IGRA) test has the characteristics of short time, high specificity, and high sensitivity, but it lacks the correlation research between TB-IGRA test results and body's immune cells, disease progression and prognosis, which is explored in this study. DESIGN: A retrospective study was carried out on positive TB-IGRA patients who were infected with TB and diagnosed at our hospital from January 2014 to June 2015. The TB-IGRA, routine blood test, T-cell subgroup data were collected for statistical analysis. RESULTS: TB-IGRA results were in positive proportion to the lymphocytes, CD4+ T cells and CD4+ CD28+ T cells, whereas negative to the Treg cells. Patient with unilateral pulmonary lesion had higher TB-IGRA than those with bilateral pulmonary lesions. After the stimulation of TB-specific antigen, the proportion of CD4+ IFN-γ+ and CD8+ IFN-γ+ T Tcells were both increased and the CD4+ IFN-γ+ T had positive correlation with the value of TB-IGRA. CONCLUSIONS: IFN-γ was tested with TB-IGRA in patients with TB by the specific TB T cells and correlated with the lymphocytes, while the lymphocytes also closely related to the host's anti-TB immunity and disease outcome. Hence the result of TB-IGRA could reflect the specific anti-TB immunity ability of the host, disease progression and prognosis. This study further expands the application scope of TB-IGRA technology in the diagnosis of TB and lays a foundation for clinical practice to understand the immunity state of the patients with TB and the application of auxiliary clinical immunity regulators.


Asunto(s)
Ensayos de Liberación de Interferón gamma/estadística & datos numéricos , Tuberculosis/inmunología , Adulto , Linfocitos T CD4-Positivos/inmunología , Femenino , Humanos , Interferón gamma/análisis , Interferón gamma/inmunología , Interferón gamma/metabolismo , Leucocitos Mononucleares/inmunología , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Tuberculosis/diagnóstico , Tuberculosis/epidemiología
11.
Artículo en Inglés | MEDLINE | ID: mdl-32476829

RESUMEN

A 32-year-old woman was diagnosed as pulmonary tuberculosis 15 years ago and recurred several times due to long-term nonstandard treatment. Drug sensitivity test indicated that multidrug-resistant tuberculosis had emerged and we determined relevant therapeutic schedule according to this result. However, it didn't show any amelioration of the disease after 3-month chemotherapy. We formulated 3-course CIK immunotherapy based on patient's condition. After 3 courses of immunotherapy, we found obvious amelioration of the patient's condition. And there was no recurrence during the follow-up in the past 3 years. Therefore, we considered that the CIK immunotherapy is an effective method for tuberculosis treatment and recurrence prevention. (Sarcoidosis Vasc Diffuse Lung Dis 2017; 34: 97-99).

12.
CBE Life Sci Educ ; 15(4)2016.
Artículo en Inglés | MEDLINE | ID: mdl-27909026

RESUMEN

The benefits of introducing active learning in college science courses are well established, yet more needs to be understood about student buy-in to active learning and how that process of buy-in might relate to student outcomes. We test the exposure-persuasion-identification-commitment (EPIC) process model of buy-in, here applied to student (n = 245) engagement in an undergraduate science course featuring active learning. Student buy-in to active learning was positively associated with engagement in self-regulated learning and students' course performance. The positive associations among buy-in, self-regulated learning, and course performance suggest buy-in as a potentially important factor leading to student engagement and other student outcomes. These findings are particularly salient in course contexts featuring active learning, which encourage active student participation in the learning process.


Asunto(s)
Curriculum , Aprendizaje Basado en Problemas , Ciencia/educación , Estudiantes , Universidades , Adolescente , Adulto , Demografía , Femenino , Humanos , Masculino , Modelos Educacionales , Negociación , Adulto Joven
13.
Adv Physiol Educ ; 39(2): 102-7, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26031726

RESUMEN

Laboratory courses serve as important gateways to science, technology, engineering, and mathematics education. One of the challenges in assessing laboratory learning is to conduct meaningful and standardized practical exams, especially for large multisection laboratory courses. Laboratory practical exams in life sciences courses are frequently administered by asking students to move from station to station to answer questions, apply knowledge gained during laboratory experiments, interpret data, and identify various tissues and organs using various microscopic and gross specimens. This approach puts a stringent time limit on all questions regardless of the level of difficulty and also invariably increases the potential risk of cheating. To avoid potential cheating in laboratory courses with multiple sections, the setup for practical exams is often changed in some way between sections. In laboratory courses with multiple instructors or teaching assistants, practical exams may be handled inconsistently among different laboratory sections, due to differences in background knowledge, perceptions of the laboratory goals, or prior teaching experience. In this article, we describe a design for a laboratory practical exam that aims to align the assessment questions with well-defined laboratory learning objectives and improve the consistency among all laboratory sections.


Asunto(s)
Disciplinas de las Ciencias Biológicas/educación , Educación Profesional/normas , Evaluación Educacional/normas , Laboratorios/normas , Encuestas y Cuestionarios/normas , Enseñanza/normas , Instrucción por Computador/normas , Curriculum , Educación Profesional/métodos , Escolaridad , Humanos , Aprendizaje , Desarrollo de Programa , Control de Calidad , Enseñanza/métodos , Factores de Tiempo
14.
World J Gastroenterol ; 20(28): 9519-27, 2014 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-25071347

RESUMEN

AIM: To investigate the protective effects of remote ischemic postconditioning (RIP) against limb ischemia-reperfusion (IR)-induced gastric mucosal injury. METHODS: Gastric IR was established in male Wistar rats by placing an elastic rubber band under a pressure of 290-310 mmHg on the proximal part of both lower limbs for 3 h followed by reperfusion for 0, 1, 3, 6, 12 or 24 h. RIP was performed using three cycles of 30 s of reperfusion and 30 s of reocclusion of the femoral aortic immediately after IR and before reperfusion for up to 24 h. Rats were randomly assigned to receive IR (n = 36), IR followed by RIP (n = 36), or sham treatment (n = 36). Gastric tissue samples were collected from six animals in each group at each timepoint and processed to determine levels of malondialdehyde (MDA), superoxide dismutase (SOD), xanthine oxidase (XOD) and myeloperoxidase (MPO). Additional samples were processed for histologic analysis by hematoxylin and eosin staining. Blood samples were similarly collected to determine serum levels of lactate dehydrogenase (LDH), creatine kinase (CK), tumor necrosis factor (TNF)-α and interleukin (IL)-10. RESULTS: The pathologic changes in gastric tissue induced by IR were observed by light microscopy. Administration of RIP dramatically reduced the gastric damage score after 6 h of reperfusion (5.85 ± 0.22 vs 7.72 ± 0.43; P < 0.01). In addition, RIP treatment decreased the serum activities of LDH (3.31 ± 0.32 vs 6.46 ± 0.03; P < 0.01), CK (1.94 ± 0.20 vs 4.54 ± 0.19; P < 0.01) and the concentration of TNF-α (53.82 ± 0.85 vs 88.50 ± 3.08; P < 0.01), and elevated the concentration of IL-10 (101.46 ± 5.08 vs 99.77 ± 4.32; P < 0.01) induced by IR at 6 h. Furthermore, RIP treatment prevented the marked elevation in MDA (3.79 ± 0.29 vs 6.39 ± 0.81) content, XOD (7.81 ± 0.75 vs 10.37 ± 2.47) and MPO (0.47 ± 0.05 vs 0.82 ± 0.03) activities, and decrease in SOD (4.95 ± 0.32 vs 3.41 ± 0.38; P < 0.01) activity in the gastric tissue as measured at 6 h. CONCLUSION: RIP provides effective functional protection and prevents cell injury to gastric tissue induced by limb IR via anti-inflammatory and antioxidant actions.


Asunto(s)
Mucosa Gástrica/irrigación sanguínea , Miembro Posterior/irrigación sanguínea , Precondicionamiento Isquémico/métodos , Daño por Reperfusión/prevención & control , Animales , Antioxidantes/metabolismo , Biomarcadores/sangre , Modelos Animales de Enfermedad , Mucosa Gástrica/metabolismo , Mucosa Gástrica/patología , Mediadores de Inflamación/sangre , Masculino , Ratas Wistar , Flujo Sanguíneo Regional , Daño por Reperfusión/sangre , Daño por Reperfusión/etiología , Daño por Reperfusión/patología , Factores de Tiempo , Torniquetes
16.
J Neurophysiol ; 107(5): 1489-99, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22131386

RESUMEN

Nitric oxide (NO) is an important signaling molecule that regulates numerous physiological processes, including activity of respiratory motoneurons. However, molecular mechanism(s) underlying NO modulation of motoneurons remain obscure. Here, we used a combination of in vivo and in vitro recording techniques to examine NO modulation of motoneurons in the hypoglossal motor nucleus (HMN). Microperfusion of diethylamine (DEA; an NO donor) into the HMN of anesthetized adult rats increased genioglossus muscle activity. In the brain slice, whole cell current-clamp recordings from hypoglossal motoneurons showed that exposure to DEA depolarized membrane potential and increased responsiveness to depolarizing current injections. Under voltage-clamp conditions, we found that NO inhibited a Ba(2+)-sensitive background K(+) conductance and activated a Cs(+)-sensitive hyperpolarization-activated inward current (I(h)). When I(h) was blocked with Cs(+) or ZD-7288, the NO-sensitive K(+) conductance exhibited properties similar to TWIK-related acid-sensitive K(+) (TASK) channels, i.e., voltage independent, resistant to tetraethylammonium and 4-aminopyridine but inhibited by methanandamide. The soluble guanylyl cyclase blocker 1H-(1,2,4)oxadiazole(4,3-a)quinoxaline-1-one (ODQ) and the PKG blocker KT-5823 both decreased NO modulation of this TASK-like conductance. To characterize modulation of I(h) in relative isolation, we tested effects of NO in the presence of Ba(2+) to block TASK channels. Under these conditions, NO activated both the instantaneous (I(inst)) and time-dependent (I(ss)) components of I(h). Interestingly, at more hyperpolarized potentials NO preferentially increased I(inst). The effects of NO on I(h) were retained in the presence of ODQ and blocked by the cysteine-specific oxidant N-ethylmaleimide. These results suggest that NO activates hypoglossal motoneurons by cGMP-dependent inhibition of a TASK-like current and S-nitrosylation-dependent activation of I(h).


Asunto(s)
GMP Cíclico/fisiología , Canales Catiónicos Regulados por Nucleótidos Cíclicos/metabolismo , Nervio Hipogloso/fisiología , Neuronas Motoras/fisiología , Óxido Nítrico/fisiología , Canales de Potasio de Dominio Poro en Tándem/antagonistas & inhibidores , Canales de Potasio de Dominio Poro en Tándem/fisiología , Animales , Masculino , Proteínas del Tejido Nervioso , Ratas , Ratas Wistar
17.
Microbiol Immunol ; 55(4): 217-23, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21272062

RESUMEN

The purpose of this study was to assess human ß-defensin-2 (hBD-2) gene transfection in human bladder epithelial cells and its therapeutic efficacy in a rat urinary tract infection (UTI) model via liposome mediated gene transfer. A large amount of hBD2 production (36.5 ± 3.2 ng/10(6) cells) was demonstrated in transfected cells' supernatants. In addition, a detectable amount of hBD-2 was identified in rats' urine (4.77 ± 1.4 ng/mL) by ELISA. Expression of the transgene hBD-2 in transfected cells and rats' bladders was also confirmed by RT-PCR and Western blotting. Immunohistochemistry revealed that the transgene hBD-2 expressed in the entire epithelial layer of the transduced bladders. Numbers of bacterial colony-forming units in urine and bladders from hBD2 gene treated UTI rats were significantly lower than those from the UTI rats administered PBS at 24, 36, and 72 hr after infection (P < 0.05). In addition, in vivo expression of hBD-2 reduced mucosal damage, interstitial edema and inflammatory cell infiltration in UTI animals. The results indicate that successful inhibition of UTI progression can be produced by hBD2 gene therapy. The liposome-mediated hBD2 plasmid DNA transfection system appears to be a promising method for antimicrobial gene therapy of UTI.


Asunto(s)
Terapia Genética/métodos , Transfección/métodos , Infecciones Urinarias/genética , Infecciones Urinarias/terapia , beta-Defensinas/genética , Administración Intravesical , Animales , Línea Celular , Modelos Animales de Enfermedad , Femenino , Terapia Genética/instrumentación , Humanos , Liposomas , Ratones , Ratas , Ratas Wistar , Transfección/instrumentación , Infecciones Urinarias/microbiología , beta-Defensinas/administración & dosificación , beta-Defensinas/uso terapéutico
18.
Neuroreport ; 21(17): 1116-20, 2010 Dec 08.
Artículo en Inglés | MEDLINE | ID: mdl-20890228

RESUMEN

We sought to understand the mechanisms underlying glucose sensing in Drosophila melanogaster. We found that insulin-producing cells (IPCs) of adult Drosophila respond to glucose and glibenclamide with a burst-like pattern of activity. Under controlled conditions IPCs have a resting membrane potential of -62+/-4 mV. In response to glucose or glibenclamide, IPCs generate action potentials at a threshold of -36+/-1.4 mV with an amplitude of 46+/-4 mV and width of 9.3+/-1.8 ms. Real-time Ca imaging confirms that IPCs respond to glucose and glibenclamide with increased intracellular Ca. These results provide the first detailed characterization of electrical properties of IPCs of adult Drosophila and suggest that these cells sense glucose by a mechanism similar to mammalian pancreatic ß cells.


Asunto(s)
Calcio/fisiología , Drosophila melanogaster/citología , Drosophila melanogaster/metabolismo , Glucosa/metabolismo , Células Secretoras de Insulina/fisiología , Insulina/metabolismo , Canales KATP/fisiología , Animales , Señalización del Calcio/efectos de los fármacos , Señalización del Calcio/fisiología , Drosophila melanogaster/fisiología , Glucosa/farmacología , Gliburida/farmacología , Homeostasis/efectos de los fármacos , Homeostasis/fisiología , Hipoglucemiantes/farmacología , Secreción de Insulina , Células Secretoras de Insulina/citología , Células Secretoras de Insulina/efectos de los fármacos , Canales KATP/efectos de los fármacos , Potenciales de la Membrana/efectos de los fármacos , Potenciales de la Membrana/fisiología , Modelos Animales
19.
Int J Neural Syst ; 19(5): 309-30, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19885961

RESUMEN

A linear third-order model of the ocular motor plant for horizontal saccadic eye movements is presented consisting of a linear ocular motor plant and a time-optimal saccadic controller based on physiological considerations. The ocular motor plant consists of the eyeball and two extraocular muscles. All parameters and initial conditions are estimated or measured from physiological data. The neural inputs are described by pulse-slide-step waveforms with a post inhibitory rebound burst and based on a time-optimal controller. Model parameters are estimated using the system identification technique. The static and dynamic behaviors of the model are in excellent agreement with the experimental data.


Asunto(s)
Potenciales de Acción/fisiología , Modelos Neurológicos , Neuronas/fisiología , Movimientos Sacádicos/fisiología , Vías Visuales/fisiología , Algoritmos , Animales , Humanos , Macaca mulatta , Red Nerviosa/fisiología , Músculos Oculomotores/fisiología , Orientación/fisiología , Factores de Tiempo
20.
IEEE Trans Biomed Eng ; 55(8): 1966-72, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18632359

RESUMEN

Calculation of approximate entropy (ApEn) requires a priori determination of two unknown parameters, m and r. While the recommended values of r, in the range of 0.1-0.2 times the standard deviation of the signal, have been shown to be applicable for a wide variety of signals, in certain cases, r values within this prescribed range can lead to an incorrect assessment of the complexity of a given signal. To circumvent this limitation, we recently advocated finding the maximum ApEn value by assessing all values of r from 0 to 1, and found that maximum ApEn does not always occur within the prescribed range of r values. Our results indicate that finding the maximum ApEn leads to the correct interpretation of a signal's complexity. One major limitation, however, is that the calculation of all choices of r values is often impractical due to the computational burden. Our new method, based on a heuristic stochastic model, overcomes this computational burden, and leads to the automatic selection of the maximum ApEn value for any given signal. Based on Monte Carlo simulations, we derive general equations that can be used to estimate the maximum ApEn with high accuracy for a given value of m. Application to both synthetic and experimental data confirmed the advantages claimed with the proposed approach.


Asunto(s)
Algoritmos , Inteligencia Artificial , Modelos Biológicos , Reconocimiento de Normas Patrones Automatizadas/métodos , Procesamiento de Señales Asistido por Computador , Simulación por Computador , Diagnóstico por Computador , Entropía
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