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1.
Facts Views Vis Obgyn ; 15(3): 251-258, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37742202

RESUMEN

Background: Coronavirus disease 19 (COVID-19) has affected many aspects of the lives of medical professionals. Postgraduate training has also been affected and mitigation plans are still ongoing. Objective: To understand the perspectives of trainees in obstetrics and gynaecology (ObGyn) during the pandemic. Materials and Methods: A cross-sectional exploratory survey conducted electronically from 20th of April 2020 to 1st July 2020. Main outcome measures: The original questionnaire comprised of 40 questions and a free-text option. The free-text questions covered five main domains: effect of the pandemic on training, worries about training, acquisition of skills during the pandemic, training period and extensions and responsibilities outside training during the pandemic. The responses to these questions in the survey were analysed using pragmatic thematic analysis. Results: Trainees felt there was lack of training as well as training opportunities. Some took the pandemic as an opportunity to gain new skills. Trainees were also worried about time in training and uncertainty about extensions. Lastly, many had concerns pertaining to patient care, an inability to contribute to departmental organisation, and dissatisfaction with the implemented policies. Conclusion: The difficulties in Obstetrics and gynaecology training due to the pandemic need to be mitigated. When planning for reshaping the training programmes to accommodate for the discrepancies caused, trainers need to consider the perspectives of trainees and actively involve them in the decision making, designing and executing future plans. What is new?: Efforts are currently underway to address the training time lost during the pandemic in Europe. Recognising the paramount importance of providing exceptional care for women and children across the continent, it becomes imperative to consider the valuable perspectives and insights offered by those who represent the future generation of specialists in the field.

2.
Neuroscience ; 87(4): 925-31, 1998 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-9759980

RESUMEN

Agonist-induced endocytosis and recycling of G protein-coupled receptors contributes to desensitization and resensitization of the receptors. In this study, we have used fluorescence immunohistochemistry, confocal microscopy and digital image analysis to quantify the proportion of receptor in the cytoplasm and on the surfaces of nerve cells in the guinea-pig ileum. With these methods we examined the dynamics of internalization of the neurokinin 1 receptor in response to agonist, return of receptor to the cell membrane and its capacity to be re-internalized in response to further exposure to agonist. The basal level of neurokinin 1 receptor immunoreactivity in the cytoplasm was 12-15% of total cellular immunoreactivity. Concentration-response relations were generated for neurokinin 1 receptor internalization after incubation of isolated ileum with 10(-11) to 10(-6) M substance P at 4 degrees C and warming to 37 degrees C for 20 min. The threshold concentration for cytoplasmic receptor to exceed baseline was 10(-11) M and the proportion of receptor in the cytoplasm increased with increasing substance P concentration. The effect of two exposures to agonist was studied using 10(-8) M and 10(-6) M substance P. After equilibration with substance P at 4 degrees C for 1 h followed by 20 min at 37 degrees C with no substance P, neurokinin 1 receptor immunoreactivity in the cytoplasm increased significantly from 12% to 36+/-3% for incubation with 10(-8) M and to 64+/-3% for 10(-6) M. When return of receptor to the surface was blocked with monensin (10(-5) M), 90% of the receptor was in the cytoplasm after 1 h at 37 degrees C following exposure to 10(-6) M substance P. After 60 min without substance P and no monensin, receptor in the cytoplasm decreased to 19+/-2% (10(-8) M) and 38+/-4% (10(-6) M). A second period of equilibration with substance P at 4 degrees C for 1 h followed by 20 min at 37 degrees C, without substance P, resulted in a second wave of endocytosis; the fractions of receptor in the cytoplasm were 47+/-2% (10(-8) M) and 70 2% (10(-6) M). These results indicate that most of the receptors on the cell surface are available for internalization and that the receptors that return to the cell surface after endocytosis rapidly regain their ability to bind ligand and undergo endocytosis.


Asunto(s)
Endocitosis , Plexo Mientérico/metabolismo , Proteínas del Tejido Nervioso/metabolismo , Neuronas/metabolismo , Receptores de Neuroquinina-1/metabolismo , Animales , Transporte Biológico , Membrana Celular/metabolismo , Endosomas/metabolismo , Endosomas/ultraestructura , Femenino , Proteínas de Unión al GTP/metabolismo , Cobayas , Calor , Íleon/inervación , Masculino , Microscopía Confocal , Monensina/farmacología , Plexo Mientérico/citología , Receptores de Neuroquinina-1/agonistas , Sustancia P/administración & dosificación , Sustancia P/farmacología
3.
Science ; 231(4742): 1200, 1986 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-17818556
4.
J Insur Med ; 33(3): 277-89, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11558411

RESUMEN

Evaluation of applicants for life insurance who have elevations of their liver function tests or an increased probability of alcohol abuse has always been difficult for underwriters. This paper reports the results of an intercompany study in which the pooled mortality experience of a group of insureds with evidence of alcohol abuse, an adverse driving record or elevations of the liver transaminases or gamma-glutamyl transferase is summarized.


Asunto(s)
Alcoholismo , Hepatopatías , Adulto , Anciano , Alcoholismo/enzimología , Alcoholismo/mortalidad , Aspartato Aminotransferasas/sangre , Conducción de Automóvil , Biomarcadores/sangre , Femenino , Humanos , Seguro de Vida , Hepatopatías/enzimología , Hepatopatías/mortalidad , Masculino , Persona de Mediana Edad , Factores Sexuales , Encuestas y Cuestionarios , gamma-Glutamiltransferasa/sangre
5.
Histochem Cell Biol ; 106(6): 563-71, 1996 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-8985744

RESUMEN

Immunoreactivity for NK1 receptors is confined to specific nerve cell bodies in the guinea-pigileum, including inhibitory motor neurons and secretomotor neurons. In the present work, endocytosis of NK1 receptors in these enteric neurons was studied following addition of substance P (SP) to isolated ileum. NK1 receptors were localised with antibodies against the C-terminus of this receptor. Some preparations were incubated with SP tagged with the fluorescent label, Cy3.18, so that the fate of SP bound to receptors could be followed. Preparations were analysed by confocal microscopy. In tissue that was incubated at 4 degrees C in the absence of SP, most NK1 receptor immunoreactivity (IR) was confined to surface membranes of nerve cells. At 37 degrees C in the presence of 10(-7) M SP (plus 3 x 10(-7)M tetrodotoxin to prevent indirect activation via other neurons) the neuronal NK1 receptor was rapidly internalised. After 5 min, NK1 receptor IR was partially internalised, at 20 min NK1 receptor IR was throughout the cytoplasm and in perinuclear aggregates and at 30 min it was again at the cell surface. SP-induced NK1 receptor endocytosis was inhibited by the specific NK1 receptor antagonist, SR140333. Cy3-SP was colocalised with NK1 receptor IR and was internalised with the NK1 receptor. These results show that enteric neurons exhibit authentic NK1 receptors that are rapidly internalised when exposed to their preferred ligand.


Asunto(s)
Endocitosis/fisiología , Neuronas/química , Receptores de Neuroquinina-1/metabolismo , Sustancia P/metabolismo , Animales , Anticuerpos Bloqueadores , Endocitosis/efectos de los fármacos , Femenino , Colorantes Fluorescentes , Cobayas , Intestino Delgado/química , Intestino Delgado/citología , Intestino Delgado/inervación , Ligandos , Masculino , Microscopía Confocal , Neuronas/citología , Neuronas/metabolismo , Receptores de Neuroquinina-1/agonistas , Receptores de Neuroquinina-1/inmunología , Sustancia P/farmacología
6.
Cell Tissue Res ; 292(1): 37-45, 1998 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-9506910

RESUMEN

Agitation of villi evokes reflexes that affect the motility of the guinea-pig small intestine. NK1 receptor endocytosis was used to investigate the possible involvement of tachykinins acting on neuronal NK1 receptors in these reflexes. Segments of guinea-pig ileum were incubated at 37 degrees C in Krebs physiological saline containing 3x10(-6) M nicardipine, with or without agitation of the villi by gas bubbles. Gut segments were fixed after 0-75 min and processed for immunohistochemistry to reveal the NK1 receptors, following which cells were imaged by confocal microscopy. Initially, receptors were located on the surface and in the cytoplasm of myenteric neurons. In gut incubated without movement of the villi, NK1 receptors returned to the cell surface. After 45 and 60 min, NK1 receptors were detected almost exclusively at the cell surface of 83% and 97% (respectively) of nerve cells that were immunoreactive for NK1 receptors and only 12%-13% of the NK1 receptor fluorescence was located in the cytoplasm. Following the return of receptor to the cell surface, agitation of the villi caused a new wave of endocytosis of the NK1 receptors in 70%-80% of the NK1 receptor-immunoreactive neurons. The percentage of the NK1 receptor fluorescence that was in the cytoplasm increased more than 2-fold to 27+/-2% after 15 min villous agitation. Action potential blockade by tetrodotoxin (3x10(-7) M) prevented the internalisation of the NK1 receptor in response to villous agitation. The degree of internalisation caused by bubbling was similar to that caused by 2x10(-9) M substance P. These results indicate that, when enteric reflex circuits are activated by villous movement, tachykinins are released and cause endocytosis of the NK1 receptor in a subpopulation of myenteric neurons.


Asunto(s)
Endocitosis/fisiología , Íleon/inervación , Mucosa Intestinal/fisiología , Mucosa Intestinal/ultraestructura , Plexo Mientérico/metabolismo , Neuronas Aferentes/metabolismo , Receptores de Neuroquinina-1/metabolismo , Animales , Membrana Celular/metabolismo , Relación Dosis-Respuesta a Droga , Endocitosis/efectos de los fármacos , Femenino , Motilidad Gastrointestinal/fisiología , Cobayas , Técnicas In Vitro , Mucosa Intestinal/metabolismo , Masculino , Microvellosidades/fisiología , Plexo Mientérico/fisiología , Neuronas Aferentes/efectos de los fármacos , Neuronas Aferentes/fisiología , Tetrodotoxina/farmacología
7.
J Auton Nerv Syst ; 52(2-3): 107-16, 1995 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-7542292

RESUMEN

Retrograde dye tracing was combined with immunohistochemistry to determine the distributions of nitric oxide synthase (NOS) immunoreactive nerve cells that project to prevertebral ganglia from the gastrointestinal tract and spinal cord of the guinea pig. An antiserum was raised against the neuronal form of NOS by selecting an amino-acid sequence specific to this form as immunogen. The antiserum recognised a single band at 150 kDa on Western blots of rat brain extract. Enteric nerve cells that were labelled by Fast Blue injected into the coeliac ganglion were not NOS immunoreactive in the small intestine, whereas 40-70% were reactive in the large intestine. Retrograde dye injected into the inferior mesenteric ganglion labels cells in the colon and rectum; 60-70% were immunoreactive for NOS. The NOS-immunoreactive nerve fibres arising in the intestine appear to end selectively around somatostatin-immunoreactive nerve cells in the coeliac and inferior mesenteric ganglia. Preganglionic nerve cell bodies in the intermediolateral column and dorsal commissural nucleus from T12 to L2 were labelled from the inferior mesenteric ganglion. Nearly 70% of neurons at each level were NOS immunoreactive. Thus, two sources of NOS terminals in prevertebral ganglia have been identified, intestinofugal neurons of the large, but not the small intestine, and sympathetic preganglionic neurons.


Asunto(s)
Aminoácido Oxidorreductasas/metabolismo , Ganglios Autónomos/metabolismo , Neuronas/enzimología , Amidinas , Secuencia de Aminoácidos , Animales , Western Blotting , Femenino , Colorantes Fluorescentes , Ganglios Autónomos/citología , Ganglios Simpáticos/citología , Ganglios Simpáticos/enzimología , Cobayas , Inmunohistoquímica , Masculino , Datos de Secuencia Molecular , Óxido Nítrico Sintasa , Ratas
8.
Xenobiotica ; 34(10): 901-15, 2004 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-15764410

RESUMEN

The pharmacokinetics of gefitinib and its metabolites in rat and dog were investigated in preclinical studies conducted to support the safety evaluation and clinical development of gefitinib, the first EGFR tyrosine kinase inhibitor approved for the treatment of non-small-cell lung cancer. Following intravenous dosing (5 mg kg(-1), gefitinib plasma half-life was 3-6h in rats and dogs, although studies using a more sensitive HPLC-MS assay produced longer estimates of half-life (7-14h). In these studies, plasma clearance was high (male rat: 25 ml min(-1) kg(-1); female rat: 16 ml min(-1) kg(-1); male dog: 16 ml min(-1) kg(-1)), as was the volume of distribution (8.0-10.41 kg(-1) in rat; 6.31 kg(-1) in dog), and exposure in female rats was double that in males. Following administration of [14C]-gefitinib, concentrations of radioactivity in plasma exceeded gefitinib throughout the profile, indicating the presence of circulating metabolites in both rat and dog. An HPLC-MS assay was developed to measure concentrations of gefitinib and five potential metabolites in plasma. All five metabolites were detected in the rat, but at levels much lower than gefitinib. In the dog, exposure to gefitinib and M523595 was similar, with much lower concentrations of M537194 and only trace levels of the other metabolites. This profile of metabolites is similar to that observed in man.


Asunto(s)
Receptores ErbB/antagonistas & inhibidores , Proteínas Tirosina Quinasas/antagonistas & inhibidores , Quinazolinas/sangre , Quinazolinas/farmacocinética , Administración Oral , Animales , Antineoplásicos/administración & dosificación , Antineoplásicos/sangre , Antineoplásicos/farmacocinética , Perros , Evaluación Preclínica de Medicamentos , Femenino , Gefitinib , Inyecciones Intravenosas , Masculino , Inhibidores de Proteínas Quinasas/administración & dosificación , Inhibidores de Proteínas Quinasas/sangre , Inhibidores de Proteínas Quinasas/farmacocinética , Quinazolinas/administración & dosificación , Ratas , Ratas Wistar , Factores Sexuales , Especificidad de la Especie
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