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1.
Rev Sci Instrum ; 85(11): 11D819, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25430232

RESUMEN

A Nd:YAG Thomson scattering system has been developed for Heliotron J. The system consists of two 550 mJ 50 Hz lasers, large collection optics, and 25 radial channel (∼1 cm spatial resolution) interference polychromators. This measurement system achieves a S/N ratio of ∼50 for low-density plasma (ne ∼ 0.5 × 10(19) m(-3)). A time evolution of electron temperature profiles was measured with this system for a high-intensity gas-puff (HIGP) fueling neutral-beam-injection plasma. The peripheral temperature of the higher-density phase after HIGP recovers to the low-density pre-HIGP level, suggesting that improving particle transport in the HIGP plasma may be possible.

2.
Transl Psychiatry ; 4: e393, 2014 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-24893064

RESUMEN

Empathy cultivates deeper interpersonal relationships and is important for socialization. However, frequent exposure to emotionally-demanding situations may put people at risk for burnout. Burnout has become a pervasive problem among medical professionals because occupational burnout may be highly sensitive to empathy levels. To better understand empathy-induced burnout among medical professionals, exploring the relationship between burnout severity and strength of empathy-related brain activity may be key. However, to our knowledge, this relationship has not yet been explored. We studied the relationship between self-reported burnout severity scores and psychological measures of empathic disposition, emotional dissonance and alexithymia in medical professionals to test two contradictory hypotheses: Burnout is explained by (1) 'compassion fatigue'; that is, individuals become emotionally over involved; and (2) 'emotional dissonance'; that is, a gap between felt and expressed emotion, together with reduced emotional regulation. Then, we tested whether increased or decreased empathy-related brain activity measured by fMRI was associated with burnout severity scores and psychological measures. The results showed that burnout severity of medical professionals is explained by 'reduced' empathy-related brain activity. Moreover, this reduced brain activity is correlated with stronger emotional dissonance and alexithymia scores and also greater empathic disposition. We speculate that reduced emotion recognition (that is, alexithymia) might potentially link with stronger emotional dissonance and greater burnout severity alongside empathy-related brain activity. In this view, greater empathic disposition in individuals with higher burnout levels might be due to greater difficulty identifying their own emotional reactions. Our study sheds new light on the ability to predict empathy-induced burnout.


Asunto(s)
Síntomas Afectivos/fisiopatología , Agotamiento Profesional/fisiopatología , Corteza Cerebral/fisiopatología , Empatía/fisiología , Enfermeras y Enfermeros/psicología , Adulto , Femenino , Neuroimagen Funcional , Humanos , Imagen por Resonancia Magnética , Masculino , Índice de Severidad de la Enfermedad , Adulto Joven
3.
Kyobu Geka ; 58(4): 341-3, 2005 Apr.
Artículo en Japonés | MEDLINE | ID: mdl-15828259

RESUMEN

A 51-year-old woman presented with a painful sternal lump. Nine years earlier she had undergone right modified mastectomy for breast cancer, followed by chemotherapy. Computed tomography and bone scintigraphy demonstrated a solitary sternal bone metastasis. The patient was treated by partial sternectomy. Thereafter, the sternal defect was reconstructed with Marlex mesh and rectus abdominis myocutaneous flap. The postoperative course was uneventful. The patient subsequently developed brain metastasis and died within 52 months after sternal resection. The stability of the chest wall was well preserved for the duration of follow-up.


Asunto(s)
Neoplasias Óseas/secundario , Neoplasias Óseas/cirugía , Neoplasias de la Mama/patología , Carcinoma Ductal de Mama/secundario , Esternón , Neoplasias Encefálicas/secundario , Neoplasias de la Mama/cirugía , Carcinoma Ductal de Mama/cirugía , Femenino , Humanos , Mastectomía Radical Modificada , Persona de Mediana Edad , Procedimientos de Cirugía Plástica/métodos , Recto del Abdomen/cirugía , Colgajos Quirúrgicos
4.
Dis Aquat Organ ; 56(1): 65-74, 2003 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-14524503

RESUMEN

We report the enigmatic parasite Dermocystidium ranae in a green frog population (Solomeo, Umbria, Italy) of the Rana esculenta complex, consisting of the parental species R. lessonae (L) and hybrid form R. esculenta (E). In this population a rapid 50% decline of the parental form L was observed. Large dermal U-shaped cysts of D. ranae were found primarily on the ventral aspect of infected individuals, with a significantly higher incidence of infection in the parental species compared to the clonal hybrid. In each form, however, there was little pathological change associated with infection, and the cause of the recent declines of R. lessonae at this site remains unknown. In this paper we present the first ultrastructural description of an amphibian Dermocystidium sp. and we review the taxonomy of Dermocystidium, Dermosporidium and Dermomycoides spp. from amphibians. We conclude that Dermosporidium multigranulare Broz & Kulda, 1954 is synonymous with Dermocystidium ranae Guyénot & Naville, 1922 and, due to lack of sufficient differences between genera and significant dissimilarities with fish Dermocystidium spp., the 3 amphibian genera are synonymous. We propose that they should be designated to a new genus, Amphibiocystidium n. gen., and Dermocystidium retained for those species parasitic in fish.


Asunto(s)
Hongos/clasificación , Hongos/fisiología , Hongos/ultraestructura , Rana esculenta/parasitología , Animales , Interacciones Huésped-Parásitos , Italia , Microscopía Electrónica , Filogenia
5.
Eur J Morphol ; 39(4): 215-21, 2001 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11880936

RESUMEN

In this study the ultrastructure of Rana esculenta skin is described. Cytochemical methods were used to localize guanylate cyclase in the presence of atrial natriuretic peptide and immunocytochemical methods showed the presence of the atrial natriuretic peptide in various levels of skin. The peptide is mainly found in the epithelium and in the lymph sacs of the tela subcutanea. Its receptors are located in the same zones and are indicated by guanylate cyclase activity. We demonstrate that frog skin is a target organ for atrial natriuretic peptide and propose that, at this level, the peptide carries out an important osmoregulatory role.


Asunto(s)
Factor Natriurético Atrial/biosíntesis , Animales , Epitelio/metabolismo , Epitelio/ultraestructura , Histocitoquímica , Inmunohistoquímica , Rana esculenta
6.
Eur J Morphol ; 38(1): 41-50, 2000 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10550800

RESUMEN

In this study on the internal gills of the larvae of Bufo bufo we examined the ultrastructural features and, using cytochemical methods, showed the localization of guanylate cyclase in the presence of atrial natriuretic peptide. The gill apparatus consists of a series of arches each with a dorsal part or gill rakers with filtering and glandular functions. In the epithelium, cells were found that contain granular secretions similar to those atrial natriuretic factor-immunoreactive granules of larval Bufo arenarum gill rakers. The ventral portion of the gill arches is made up of gill tufts with a respiratory function. The cytochemical localization of the guanylate cyclase in the presence of exogenous atrial natriuretic peptide demonstrates that the internal gills of the larvae are an important target organ for the peptide and therefore, it is proposed that, at this level, the atrial natriuretic peptide carries out an important osmoregulatory role.


Asunto(s)
Factor Natriurético Atrial/fisiología , Bufonidae/crecimiento & desarrollo , Bufonidae/metabolismo , Branquias/enzimología , Guanilato Ciclasa/metabolismo , Animales , Factor Natriurético Atrial/farmacología , Branquias/efectos de los fármacos , Branquias/crecimiento & desarrollo , Branquias/ultraestructura , Histocitoquímica , Larva/enzimología , Larva/ultraestructura , Microscopía Electrónica , Distribución Tisular
7.
Anat Histol Embryol ; 28(1): 31-7, 1999 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10208032

RESUMEN

The carpal organ of adult female wild swine is a sweat-type gland which secretes an odorous substance. The gland consists of 5-7 lobes, each made up of lobules with convoluted glandular tubules. The gland secretion is transported in large excretory canals which empty from 5 to 7 clearly visible pores. An ultrastructural examination showed that the glandular tubules are made up of single-layered epithelium with different types of cells. One type, with rather electron-dense cytoplasm, is secretory cells full of granular material which empties into the tubule lumen. A second cell type has a glycogen-rich, transparent cytoplasm. Its role appears to be secreting a watery, electrolyte-containing liquid. In the intermediate zone of the tubules, there is a third type of cell with transparent cytoplasm. Its ultrastructural characteristics seem to indicate that its function is to reabsorb the excess watery component. In the wall of the glandular tubules, outside the epithelium, there are myoepithelial cells which facilitate the movement of the secretions toward the collector canal.


Asunto(s)
Glándulas Sudoríparas/anatomía & histología , Porcinos/anatomía & histología , Animales , Animales Salvajes , Citoplasma/ultraestructura , Femenino , Miembro Anterior , Fibras Nerviosas/ultraestructura , Glándulas Sudoríparas/citología , Glándulas Sudoríparas/ultraestructura
8.
J Submicrosc Cytol Pathol ; 30(3): 355-63, 1998 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-9723195

RESUMEN

The ultracytochemical localization of particulate guanylate cyclase (GC) has been studied in Rana esculenta choroid plexus after activation with rat atrial natriuretic peptide (ANP), porcine brain natriuretic peptide (BNP) and porcine C-type natriuretic peptide (CNP). This study shows that the three peptides are activators of GC in the choroid plexus as demonstrated by the presence of reaction products at the level of the epithelium and sinusoids. In the apical zone of the epithelial cells predominantly BNP seems to activate GC, while ANP and CNP activate GC mainly at the level of the lateral surfaces. Moreover, ANP stimulates the enzyme along the basal membrane of the epithelial cells as well as the membranes of the endothelium of the sinusoids. In the presence of CNP, enzyme stimulation can also be found at the level of the endocellular membranes. These results confirm that the choroid plexus is an organ with receptors for the natriuretic peptides which are involved in the processes of osmoregulation and the control of cerebrospinal fluid production.


Asunto(s)
Factor Natriurético Atrial/farmacología , Plexo Coroideo/enzimología , Guanilato Ciclasa/metabolismo , Proteínas del Tejido Nervioso/farmacología , Proteínas/farmacología , Animales , Membrana Celular/efectos de los fármacos , Membrana Celular/enzimología , Membrana Celular/ultraestructura , Plexo Coroideo/ultraestructura , Activación Enzimática , Células Epiteliales/enzimología , Células Epiteliales/ultraestructura , Guanilato Ciclasa/análisis , Microscopía Electrónica , Péptido Natriurético Encefálico , Péptido Natriurético Tipo-C , Rana esculenta , Ratas , Porcinos
9.
Microsc Res Tech ; 40(6): 446-54, 1998 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-9551625

RESUMEN

The importance of cyclic nucleotides in the regulation of the processes of differentiation and embryonic development is known. The possible role that cyclic adenosine monophosphate (cAMP) plays during the development of the posterior limb of Bufo bufo is studied by the cytochemical localization of adenylate cyclase (AC), an enzyme that catalyzes the synthesis of the cyclic nucleotide. The method is based on the reaction between the enzyme AC and its specific substrate AMP-PNP (5'-adenylylimidodiphosphate) in the presence of lead. The lead precipitates that form as secondary reaction products are evidence of enzymatic activity. Reaction products are present only at the epithelial level in the limb bud; initially, such products are visible only at the base of the bud, particularly on the epithelial fascia located at the boundary with the body. During successive elongation and toe formation, AC activity is only present on the cells of the proximal portion of each new segment. Enzymatic activity is never present in correspondence to the ectodermal apical crest. cAMP is probably not involved in the processes of cellular proliferation but, rather, in the processes of inducing differentiation of the internal mesenchymal cells.


Asunto(s)
Adenilil Ciclasas/análisis , Embrión no Mamífero/enzimología , Miembro Posterior/enzimología , Esbozos de los Miembros/enzimología , Animales , Bufo bufo , Diferenciación Celular , AMP Cíclico/biosíntesis , Epitelio/enzimología , Epitelio/ultraestructura , Miembro Posterior/embriología , Miembro Posterior/crecimiento & desarrollo , Larva , Esbozos de los Miembros/embriología , Esbozos de los Miembros/crecimiento & desarrollo , Esbozos de los Miembros/ultraestructura , Microscopía Electrónica , Morfogénesis/fisiología
10.
Nihon Sanka Fujinka Gakkai Zasshi ; 48(10): 883-7, 1996 Oct.
Artículo en Japonés | MEDLINE | ID: mdl-8921520

RESUMEN

The aim of this study was to determine the influence of cytoreductive surgery followed by chemotherapy on quality of life (QOL) in patients with advanced ovarian cancer. A total of 33 patients, who underwent the treatment after telling the truth and gave us the information on QOL 11 to 42 months after the discharge, were entered into the present study. Survival and length of hospital stay were calculated. QOL including emotional and physical well-being were assessed with a structure questionnaire which gives 110 points as full marks. The estimated 5-year survival rate was 49.6%. The mean survival time and length of hospital stay were 1,257 and 382 days, respectively. The mean QOL score was estimated to be 93.2. THe scores for both sociality and mentality showed a tendency to increase after completion of the treatment. Thirty-two of 33 cases (97.0%) obtained a good response for telling the truth. Alopecia and emesis due to chemotherapy were serious problems for patients. The present study showed that telling the truth was useful for well-informed consent and the QOL of patients with advanced ovarian cancer was not disturbed by cytoreductive surgery or chemotherapy.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Histerectomía , Neoplasias Ováricas/rehabilitación , Calidad de Vida , Cisplatino/administración & dosificación , Ciclofosfamida/administración & dosificación , Doxorrubicina/administración & dosificación , Femenino , Humanos , Persona de Mediana Edad , Neoplasias Ováricas/tratamiento farmacológico , Neoplasias Ováricas/cirugía , Encuestas y Cuestionarios
11.
Brain Res ; 705(1-2): 295-301, 1995 Dec 24.
Artículo en Inglés | MEDLINE | ID: mdl-8821760

RESUMEN

This study shows that in the choroid plexus of Rana esculenta particulate guanylate cyclase (GC) is appreciably stimulated by porcine brain natriuretic peptide (BNP). Ultracytochemical tests for GC show that BNP notably increases the enzymatic reaction product along the apical surfaces of the epithelial cells. It can therefore be hypothesized that the apical zone of the epithelial cells possess receptors which have a particular affinity for BNP produced in the central nervous system and dumped into the cerebrospinal fluid. These results, together with those of a previous study [32], confirm that the choroid plexus is an organ which has receptors for the natriuretic peptides which are involved in the processes of osmoregulation and the control of cerebrospinal fluid production.


Asunto(s)
Plexo Coroideo/enzimología , Guanilato Ciclasa/metabolismo , Proteínas del Tejido Nervioso/farmacología , Animales , Epéndimo/enzimología , Células Epiteliales , Epitelio/enzimología , Guanilato Ciclasa/efectos de los fármacos , Histocitoquímica , Microscopía Electrónica , Microvellosidades/enzimología , Péptido Natriurético Encefálico , Rana esculenta , Porcinos
12.
Tissue Cell ; 27(2): 233-40, 1995 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-7778097

RESUMEN

This study shows that the choroid plexus of Rana esculenta contains a guanylate cyclase particulate (GCp), similar to that identified in Mammalia, that is quite sensitive to the atrial natriuretic factor (ANF). The cytochemical tests for GCp show that ANF increases the enzymatic reaction products. Deposits are observed on the apical portion, at the basal level and along the lateral edges of the epithelial cells, with the exclusion of some intercalary epithelial cells with reaction-lacking microvilli. In particular, ANF seems to intensely stimulate the GCp activity along the lateral membranes of the epithelial cells delimiting enlarged intercellular spaces, which are probably dilated for the transport of water and solutes. These data confirm the osmoregulatory role of the hormone and its control of cephalorachidian liquid composition.


Asunto(s)
Factor Natriurético Atrial/farmacología , Plexo Coroideo/efectos de los fármacos , GMP Cíclico/biosíntesis , Guanilato Ciclasa/metabolismo , Rana esculenta/metabolismo , Animales , Polaridad Celular/efectos de los fármacos , Plexo Coroideo/citología , Plexo Coroideo/enzimología , Células Epiteliales , Epitelio/efectos de los fármacos , Epitelio/enzimología , Histocitoquímica , Rana esculenta/anatomía & histología , Transducción de Señal/efectos de los fármacos
13.
Tissue Cell ; 26(1): 9-17, 1994 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-8171424

RESUMEN

An ultrastructural and cytochemical analysis of the anterior choroid plexus in adult Rana esculenta was undertaken. The epithelial cells are implicated in the production of cephalorachidian liquid by transporting metabolites from the blood and by synthesizing and secreting activity. The epithelial cells are also capable of re-absorbing catabolites from the cephalorachidian liquid. The presence of adenylate cyclase, along the basal and lateral membranes in some epithelial cells and along the apical membranes of others, leads us to hypothesize that the epithelium of the plexus is made up of two cell types, one type with a secretory function and another type with an absorption function.


Asunto(s)
Adenilil Ciclasas/análisis , Plexo Coroideo/enzimología , Plexo Coroideo/ultraestructura , Animales , Células Epiteliales , Epitelio/enzimología , Histocitoquímica , Rana esculenta
14.
J Morphol ; 219(1): 7-13, 1994 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-8114107

RESUMEN

A study of the ultrastructure and function of the paraphysis in Bufo bufo larvae was carried out. The structure is a tubular-ramified gland made up of numerous tubules with monolayered epithelial walls surrounded by connective tissue and sinusoids. The epithelial cells secrete glycoprotein to contribute to production of the cephalorachidian fluid. The role of the paraphysis in the transport of fluids and electrolytes from the blood to the cephalorachidian fluid in regulation of ionic and osmotic homeostasis is discussed.


Asunto(s)
Bufo bufo/anatomía & histología , Telencéfalo/ultraestructura , Animales , Vasos Sanguíneos/ultraestructura , Bufo bufo/crecimiento & desarrollo , Larva , Telencéfalo/irrigación sanguínea , Telencéfalo/crecimiento & desarrollo
15.
Comp Biochem Physiol Comp Physiol ; 105(2): 319-22, 1993 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-8101159

RESUMEN

1. During the first stages of embryonic development of Bufo bufo, the levels of cAMP and cGMP showed interesting opposite trends analogous to the trends of their respective enzymes. 2. In the late segmentation, the high increase of guanylate cyclase specific activity and the corresponding rise of embryonic level of cGMP, could indicate the involvement of this nucleotide in cellular proliferation. 3. During the following stage of the gastrulation, the increase of adenylate cyclase specific activity, coupled to the loss of guanylate cyclase specific activity, could suggest the importance of cAMP in the phenomena of differentiation induction. 4. Furthermore, the cytochemical investigation of adenylate and guanylate cyclase localization seems to confirm the prominent role of cAMP during the differentiation phases.


Asunto(s)
Adenilil Ciclasas/metabolismo , Bufo bufo/embriología , AMP Cíclico/metabolismo , GMP Cíclico/metabolismo , Guanilato Ciclasa/metabolismo , Animales , Bufo bufo/metabolismo , Diferenciación Celular/fisiología , División Celular/fisiología , Fase de Segmentación del Huevo/metabolismo , Gástrula/metabolismo , Histocitoquímica , Sistema Nervioso/embriología
16.
Anat Rec ; 227(2): 264-70, 1990 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-2350014

RESUMEN

Morphogenesis of the frontal organ in Bufo bufo was examined under transmission electron microscope. Many remarkable similarities to the frontal organ of other Amphibia Anura are observed. It originates from a diverticulum in the dorsal region of the neural tube. It is egg-shaped, has an eccentric lumen, and is made up of three kinds of cells: 1) photoreceptors, which protrude into the lumen; 2) supportive cells; and 3) ganglion cells, which make synaptic contact with the photoreceptors. Peculiar to Bufo bufo is the melanin-like pigments around the light-sensitive part of the photoreceptors. These pigments may prevent light dispersion. The frontal organ in Bufo bufo starts degenerating during the early premetamorphic stages.


Asunto(s)
Encéfalo/embriología , Bufonidae/embriología , Animales , Encéfalo/citología , Encéfalo/ultraestructura , Larva , Células Fotorreceptoras/ultraestructura
17.
J Morphol ; 204(2): 171-176, 1990 May.
Artículo en Inglés | MEDLINE | ID: mdl-29865707

RESUMEN

The mouth apparatus in Branchiobdella pentodonta was studied by electron microscopy. The opening is situated dorsal to the adhesive disk of the anterior sucker and is surrounded by a ring of 16 papillae. The papillae have mono-layered epithelium, muscle fibers, glandular processes, and taste and olfactory organs like "sensitive buttons." The oral cavity contains jaws with horny teeth and "sensitive buttons," and is surrounded by a ring of circular muscle fibers that connect to the muscle fiber of the papillae. This apparatus shows some analogies to that of Hirudinea, such as the presence of sucker and jaws with horny teeth.

20.
Cell Tissue Res ; 236(2): 345-9, 1984.
Artículo en Inglés | MEDLINE | ID: mdl-6733761

RESUMEN

The epidermal cells that migrate over the surface during the wound closure stage of head regeneration in Dugesia lugubris s.l. were examined by scanning electron microscopy. The effect of cytochalasin B on epidermal cell migration was also examined. During the first few hours after decapitation epidermal cells at the edges of the wound showed significant changes of shape related to the process of migration that was accomplished approximately 10 h after wounding. Flattening of the marginal cells was associated with active epidermal spreading throughout the healing period. Suitable support for migrating cells appeared to be a rhabditic network attached to the wound tissue. Epidermal cell migration was inhibited by cytochalasin B. These results demonstrate that the basis for cell movement in planarians is similar to that of many other systems.


Asunto(s)
Planarias/fisiología , Turbelarios/fisiología , Cicatrización de Heridas , Animales , Movimiento Celular/efectos de los fármacos , Citocalasina B/farmacología , Microscopía Electrónica de Rastreo , Regeneración , Piel/citología , Fenómenos Fisiológicos de la Piel
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