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1.
Adv Exp Med Biol ; 1194: 475-488, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32468564

RESUMEN

BACKGROUND: The European Health Risk Assessment Network on Electromagnetic Fields Exposure (EFHRAN) reported in 2012: "Children and adolescents represent the first generation of Europeans to be exposed to diffuse EMF since their conception and birth, thus, they are expected to be more sensitive to these fields." On the other hand, the body's physiologic processes are regulated by the autonomic nervous system (ANS) in a way that warrants further elucidation. OBJECTIVE: Age and duration of exposure are investigated for modifying the variance of the reported effects of mobile/cellular phone call (CPC) on ANS indexed, herein, by the heart rate variability (HRV). METHOD: Five studies targeted to 124 healthy subjects (aged 15.3-28.4 years (24.3 ± 5.2), who have been recorded in supine position before and/or sham versus real exposure (to a CPC lasting 5-32 minutes), are included in this meta-analysis. Age and duration of a CPC are evaluated as predictors in two separate meta-regressions. RESULTS: The meta-analysis identified a heterogeneity I2 = 63.2% for all outcomes and I2 = 65.2% for sympathovagal balance. Thus, we performed meta-regressions: for the sympathovagal balance rather than the combined parameters effect, the goodness of fit model presents significance only for age - the residual sum of squares compared to chi-square distribution (QR) is 4.24 for age (p = 0.12) - while, for minutes of exposure, QR = 8.2805 (p = 0.016). CONCLUSIONS: The sympathovagal balance - indispensible for health/homeostasis maintenance - is strongly predicted by age. Minutes of exposure did not affect overall HRV or sympathovagal balance. The results endorse/validate the EFHRAN 2012 suggestion for future research targeting to youngsters.


Asunto(s)
Sistema Nervioso Autónomo , Teléfono Celular , Campos Electromagnéticos , Adolescente , Adulto , Factores de Edad , Sistema Nervioso Autónomo/fisiología , Sistema Nervioso Autónomo/efectos de la radiación , Campos Electromagnéticos/efectos adversos , Voluntarios Sanos , Frecuencia Cardíaca , Humanos , Adulto Joven
2.
Int J Dent Hyg ; 9(3): 199-203, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21356019

RESUMEN

OBJECTIVES: To assess attitudes and perceptions towards oral hygiene tasks among geriatric nursing home staff, before and after a dental hygiene education. METHODOLOGY: A survey questionnaire was distributed to the nursing staff (n = 105), at a geriatric nursing home in Stockholm, Sweden. RESULTS: The response rate to the questionnaire was 83%. A vast majority (87%) of the nursing staff considered oral hygiene tasks unpleasant. The main reason for considering oral care unpleasant was a perceived unwillingness from the residents. The perceived unwillingness from the residents among the nursing staff was reduced after the dental hygiene education (chi-square test, P = 0.02). A vast majority of the nursing staff experienced, always or sometimes, resistance from the residents towards oral care. CONCLUSIONS: Nursing home staff members consider oral care tasks unpleasant, and frequently experience resistance from the nursing home residents towards oral care. The perceived unwillingness from the residents is reduced after an advanced dental hygiene education. Further studies are needed to evaluate the effects of education on nursing staff's attitudes and perceptions towards oral care tasks, with the overall aim of improving the oral health among older people in hospitals and nursing homes.


Asunto(s)
Actitud del Personal de Salud , Actitud Frente a la Salud , Hogares para Ancianos , Casas de Salud , Personal de Enfermería/psicología , Higiene Bucal , Anciano , Anciano de 80 o más Años , Terapia Cognitivo-Conductual , Demencia/enfermería , Educación en Salud Dental , Estado de Salud , Humanos , Relaciones Enfermero-Paciente , Asistentes de Enfermería/educación , Asistentes de Enfermería/psicología , Personal de Enfermería/educación , Salud Bucal , Cooperación del Paciente , Encuestas y Cuestionarios , Suecia , Enseñanza/métodos , Recursos Humanos
3.
Eur J Neurol ; 17(7): 903-12, e44-9, 2010 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-20642627

RESUMEN

BACKGROUND: Revision of the guidelines on the use of skin biopsy in the diagnosis of peripheral neuropathy, published in 2005, has become appropriate owing to publication of more relevant articles. Most of the new studies focused on small fiber neuropathy (SFN), a subtype of neuropathy for which the diagnosis was first developed through skin biopsy examination. This revision focuses on the use of this technique to diagnose SFN. METHODS: Task force members searched the Medline database from 2005, the year of the publication of the first EFNS guideline, to June 30th, 2009. All pertinent articles were rated according to the EFNS and PNS guidance. After a consensus meeting, the task force members created a manuscript that was subsequently revised by two experts (JML and JVS) in the field of peripheral neuropathy and clinical neurophysiology, who were not previously involved in the use of skin biopsy. RESULTS AND CONCLUSIONS: Distal leg skin biopsy with quantification of the linear density of intraepidermal nerve fibers (IENF), using generally agreed upon counting rules, is a reliable and efficient technique to assess the diagnosis of SFN (Recommendation Level A). Normative reference values are available for bright-field immunohistochemistry (Recommendation Level A) but not yet for confocal immunofluorescence or the blister technique. The morphometric analysis of IENF density, either performed with bright-field or immunofluorescence microscopy, should always refer to normative values matched for age (Recommendation Level A). Newly established laboratories should undergo adequate training in a well-established skin biopsy laboratory and provide their own stratified for age and gender normative values, intra- and interobserver reliability, and interlaboratory agreement. Quality control of the procedure at all levels is mandatory (Good Practice Point). Procedures to quantify subepidermal nerve fibers and autonomic innervated structures, including erector pili muscles, and skin vessels, are under development but need to be confirmed by further studies. Sweat gland innervation can be examined using an unbiased stereologic technique recently proposed (Recommendation Level B). A reduced IENF density is associated with the risk of developing neuropathic pain (Recommendation Level B), but it does not correlate with its intensity. Serial skin biopsies might be useful for detecting early changes of IENF density, which predict the progression of neuropathy, and to assess degeneration and regeneration of IENF (Recommendation Level C). However, further studies are warranted to confirm its potential usefulness as an outcome measure in clinical practice and research. Skin biopsy has not so far been useful for identifying the etiology of SFN. Finally, we emphasize that 3-mm skin biopsy at the ankle is a safe procedure based on the experience of 10 laboratories reporting absence of serious side effects in approximately 35,000 biopsies and a mere 0.19% incidence of non-serious side effects in about 15 years of practice (Good Practice Point).


Asunto(s)
Comités Consultivos , Fibras Nerviosas Mielínicas/patología , Enfermedades del Sistema Nervioso Periférico/diagnóstico , Enfermedades del Sistema Nervioso Periférico/patología , Células Receptoras Sensoriales/patología , Piel/inervación , Biopsia/métodos , Biopsia/normas , Biopsia/tendencias , Europa (Continente) , Humanos , Sociedades Médicas
4.
J Chem Phys ; 133(7): 074308, 2010 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-20726643

RESUMEN

The large polycyclic aromatic hydrocarbon molecules coronene, benzo[GHI]perylene, and anthracene have been ionized with femtosecond laser pulses at low laser intensities and the ionization process studied with velocity map imaging spectroscopy, supplemented with ion yield measurements. The electron spectra of coronene and benzo[GHI]perylene are structureless. Based on fluence and pulse duration dependence measurements, it is shown that the electron spectra are not produced in field ionization processes, and the ionization mechanism is identified to be a quasithermal statistical electron emission, previously suggested for the fullerenes C(60) and C(70). The anthracene photoelectron spectra are dominated by above threshold ionization features, but with some indication of quasithermal ionization at longer pulses.

5.
Histochem Cell Biol ; 131(2): 181-9, 2009 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18825402

RESUMEN

There are two oestrogen receptors (ERs), ERalpha and ERbeta. ERbeta protein is expressed in human skeletal muscle in the nuclei of both myofibres and endothelial cells, whether ERalpha protein is present in this tissue is unknown. We studied the expression of ERalpha protein in human skeletal muscle biopsies taken from vastus lateralis from four men, four women, two children and two postmenopausal women. Immunohistochemistry was used to determine the proportions of nuclei that were positively stained for ERalpha, the proportion of ERalpha-positive nuclei located in the muscle fibres and in capillaries and to test for possible co-expression of ERalpha and ERbeta. Both ERs were expressed in all subjects. Of all nuclei, 63% stained for ERalpha with no sex difference. ERalpha was localised both in myofibres and in endothelial cells of the capillaries, 25% of the ERalpha-positive nuclei were located in the capillaries. ERalpha and ERbeta were generally expressed in the same nuclei. The present study shows for the first time the expression of ERalpha protein in human skeletal muscle independently of age and sex. These results might improve understanding of the physiological role of oestrogen in human skeletal muscle and raise new questions about activation of ERs in skeletal muscle.


Asunto(s)
Receptor alfa de Estrógeno/análisis , Receptor beta de Estrógeno/análisis , Músculo Esquelético/química , Adulto , Factores de Edad , Núcleo Celular/química , Endotelio Vascular/química , Endotelio Vascular/ultraestructura , Femenino , Humanos , Inmunohistoquímica , Masculino , Persona de Mediana Edad , Músculo Esquelético/ultraestructura , Posmenopausia , Factores Sexuales
6.
Science ; 225(4668): 1326-34, 1984 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-6147896

RESUMEN

The development of sensitive histochemical-neuroanatomical techniques has made it possible to analyze the content of specific compounds in single nerve cells and their processes. In consequence, it has been possible to construct detailed maps of the distribution of various types of neurons on the basis of their transmitter substance. There are now many examples of neurons containing both a classical transmitter and a peptide. In some instances the peptides seem to support the action of the classical transmitters. This interaction may have applications in the prevention and treatment of nervous disease states.


Asunto(s)
Química Encefálica , Encéfalo/anatomía & histología , Animales , Técnica del Anticuerpo Fluorescente , Microscopía Fluorescente , Proteínas del Tejido Nervioso/análisis , Neuronas/análisis , Neurotransmisores/análisis , Norepinefrina/análisis , Ratas , Serotonina/análisis
7.
Science ; 184(4133): 177-9, 1974 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-4856104

RESUMEN

The existence of cortical dopamine nerve terminals is demonstrated with a highly sensitive modification of the Falck-Hillarp fluorescence technique. This confirms previous biochemical reports of high dopamine levels in the cortex. The histochemistry reveals that the distribution is regional and confined to the limbic cortex.


Asunto(s)
Dopamina/metabolismo , Sistema Límbico/metabolismo , Receptores de Droga , Esquizofrenia/metabolismo , Animales , Carbidopa/farmacología , Dihidroxifenilalanina/farmacología , Disulfuros/farmacología , Dopamina beta-Hidroxilasa/antagonistas & inhibidores , Humanos , Imidazoles/farmacología , Masculino , Microscopía Fluorescente , Ratas , Reserpina/farmacología
8.
Accid Anal Prev ; 132: 105248, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31419619

RESUMEN

E-bikes are becoming increasingly popular, and are given an important role in the green mobility of the future. However, some have raised concerns that the increased speed and the increased weight of the e-bike can lead to more accidents among cyclists riding an e-bike, as compared to conventional bicycles. Furthermore, it has been suggested that e-bikes may appeal to new groups of cyclists with little cycling experience, which may further impede cyclist safety. Previous research has not provided a clear picture. We investigate these questions with data from three surveys carried out in Norway (N = 7752). A logistic regression analysis comparing conventional and electric bicycles, controlling for age gender and exposure, shows an overall risk increase (all accidents) for e-bike users. The results suggest that this increased risk derives from females having a higher accident risk on e-bikes. For men there is no risk difference between e-bikes and conventional bikes. Some, but not all, of this elevated risk can be attributed to being unfamiliar with the bicycle. E-bikes are not more likely to cause serious accidents than conventional bicycles. In-depth analysis of accident causation showed that there was no difference in the factors leading to accidents, except that there was a somewhat higher prevalence of accidents resulting from balance problems with e-bikes.


Asunto(s)
Accidentes de Tránsito/estadística & datos numéricos , Ciclismo , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Noruega , Seguridad , Factores Sexuales , Encuestas y Cuestionarios
9.
PLoS One ; 14(5): e0216223, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31071155

RESUMEN

Satellite telemetry is an increasingly utilized technology in wildlife research, and current devices can track individual animal movements at unprecedented spatial and temporal resolutions. However, as we enter the golden age of satellite telemetry, we need an in-depth understanding of the main technological, species-specific and environmental factors that determine the success and failure of satellite tracking devices across species and habitats. Here, we assess the relative influence of such factors on the ability of satellite telemetry units to provide the expected amount and quality of data by analyzing data from over 3,000 devices deployed on 62 terrestrial species in 167 projects worldwide. We evaluate the success rate in obtaining GPS fixes as well as in transferring these fixes to the user and we evaluate failure rates. Average fix success and data transfer rates were high and were generally better predicted by species and unit characteristics, while environmental characteristics influenced the variability of performance. However, 48% of the unit deployments ended prematurely, half of them due to technical failure. Nonetheless, this study shows that the performance of satellite telemetry applications has shown improvements over time, and based on our findings, we provide further recommendations for both users and manufacturers.


Asunto(s)
Animales Salvajes/fisiología , Ecosistema , Monitoreo del Ambiente , Sistemas de Información Geográfica , Nave Espacial , Telemetría , Animales
10.
Appl Spectrosc ; 62(1): 66-72, 2008 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-18230210

RESUMEN

Photofragmentation laser-induced fluorescence (PF-LIF) is for the first time demonstrated to be a practical diagnostic tool for detection of hydrogen peroxide. Point measurements as well as two-dimensional (2D) measurements in free-flows, with nitrogen as bath gas, are reported. The present application of the PF-LIF technique involves one laser, emitting radiation of 266 nm wavelength, to dissociate hydrogen peroxide molecules into OH radicals, and another laser, emitting at 282.25 nm, to electronically excite OH, whose laser-induced fluorescence is detected. The measurement procedure is explained in detail and a suitable time separation between photolysis and excitation pulse is proposed to be on the order of a few hundred nanoseconds. With a separation time in that regime, recorded OH excitation scans were found to be thermal and the signal was close to maximum. The PF-LIF signal strength was shown to follow the same trend as the vapor pressure corresponding to the hydrogen peroxide liquid concentration. Thus, the PF-LIF signal appeared to increase linearly with hydrogen peroxide vapor-phase concentration. For 2D single shot measurements, a conservatively estimated value of the detection limit is 30 ppm. Experiments verified that for averaged point measurements the detection limit was well below 30 ppm.

11.
Med Hypotheses ; 106: 71-87, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28818275

RESUMEN

While a good number of studies have demonstrated that modern, man-made ambient electromagnetic fields can have both stimulatory and inhibitory effect on immune system function, the precise mechanisms have yet to be completely elucidated. It is hypothesized here that, depending on the parameters, one of the means by which long-term electromagnetic field exposure has the potential to eventually lead to immunosuppression is via downstream inhibition of the enzyme calcineurin - a protein phosphatase, which activates the T-cells of the immune system and can be blocked by pharmaceutical agents. Calcineurin is the target of a class of pharmaceuticals called calcineurin inhibitors (e.g., cyclosporine, pimecrolimus and tacrolimus). When organ transplant recipients take such pharmaceuticals to prevent or suppress organ transplant rejection, one of the major side effects is immunosuppression leading to increased risk of opportunistic infection: e.g., fungal, viral (Epstein-Barr virus, cytomegalovirus), atypical bacterial (Nocardia, Listeria, mycobacterial, mycoplasma), and parasitic (e.g., toxoplasmosis) infections. Frequent anecdotal reports, as well as a number of scientific studies, have shown that electromagnetic field exposures may indeed produce the same effect: a weakened immune system leading to an increase in the same or similar opportunistic infections: i.e., fungal, viral, atypical bacterial, and parasitic infections. Furthermore, numerous research studies have shown that man-made electromagnetic fields have the potential to open voltage-gated calcium channels, which can in turn produce a pathological increase of intracellular calcium, leading downstream to the pathological production of a series of reactive oxygen species. Finally, there are a number of research studies demonstrating the inhibition of calcineurin by a pathological production of reactive oxygen species. Hence, it is hypothesized here that exposures to electromagnetic fields have the potential to inhibit immune system response by means of an eventual pathological increase in the influx of calcium into the cytoplasm of the cell, which induces a pathological production of reactive oxygen species, which in turn can have an inhibitory effect on calcineurin. Calcineurin inhibition leads to immunosuppression, which in turn leads to a weakened immune system and an increase in opportunistic infection.


Asunto(s)
Inhibidores de la Calcineurina/efectos adversos , Campos Electromagnéticos/efectos adversos , Infecciones Oportunistas/etiología , Calcineurina/inmunología , Calcineurina/metabolismo , Canales de Calcio/metabolismo , Señalización del Calcio , Humanos , Tolerancia Inmunológica/efectos de los fármacos , Modelos Inmunológicos , Especies Reactivas de Oxígeno/metabolismo , Factores de Riesgo , Linfocitos T/inmunología
12.
Cancer Res ; 56(13): 2912-5, 1996 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-8674039

RESUMEN

Mutations in the breast cancer susceptibility gene 1 (BRCA1) may account for one half of all familial breast cancers. Because of the wide spectrum of different germline mutations, identification of BRCA1 mutation carriers using current techniques is laborious and difficult. The majority of the identified mutations, however, lead to aberrant expression of the gene product in tumor tissue, potentially allowing the detection of BRCA1-linked breast cancers using simple histochemical techniques. We performed quantitative mRNA in situ hybridization analysis on archival paraffin-embedded tumor specimens from 25 patients with characterized germline BRCA1 mutations or linkage and from 29 patients with sporadic breast cancers. BRCA1 mRNA levels were invariably low in tumors from BRCA1 mutation carriers. Normal breast epithelium surrounding the BRCA1 tumors showed higher mRNA levels than the tumor tissue, indicating that the low mRNA levels were due to somatic inactivation of the wild-type BRCA1 allele in the tumor tissue. The expression levels in the sporadic tumors were, on average, six times higher than in the BRCA1 tumors (P < 0.0001). The difference allowed identification of BRCA1-mutated and sporadic tumors with more than 95% specificity and sensitivity. We conclude that the analysis of BRCA1 gene expression by mRNA in situ hybridization may be useful in screening for patients with BRCA1-linked breast cancer.


Asunto(s)
Neoplasias de la Mama/genética , Mutación de Línea Germinal , Proteínas de Neoplasias/genética , ARN Mensajero/genética , Factores de Transcripción/genética , Adulto , Anciano , Proteína BRCA1 , Femenino , Marcadores Genéticos , Humanos , Hibridación in Situ , Persona de Mediana Edad , ARN Mensajero/análisis
13.
Med Hypotheses ; 86: 85-91, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26804604

RESUMEN

The International Agency for Research on Cancer recognises five viruses, one bacterium and three parasites as having a causal relationship to cancer, and one virus, HIV, that by suppressing the immune system assists in the development of cancer. In addition numerous researchers have claimed links between cancer and other viruses and bacteria, many of which have been isolated from tumours. Excluding the non-causal HIV, 33 infectious agents linked with cancer have been identified in the literature, 27 of which have one thing in common: they are all present in mosquitoes. There are over 3000 species of mosquito and very few have been fully analysed, so the six remaining infectious agents may be present in some unexamined species. This hypothesis proposes that more cancers than are presently appreciated may arise from the long-term outcome of a mosquito bite, which by releasing a complex cocktail of up to 60 infectious agents directly into the blood stream, often results in contemporaneous immuno-suppression and a multiplicity of co-infections. These co-infections may act synergistically in whole, or in part, and in complex ways. Whether and if so which type of cancer ensues will depend on the constituent ingredients in the cocktail, determined by multiple factors such as the mosquito's drinking and feeding patterns, number of previous blood-meals and the variety of intermediate hosts from which these meals are taken. Only a few mosquito species carry malaria, dengue fever, chikungunya and the other recognised serious human ailments. This hypothesis suggests that the number of species carrying the cancer cocktail will be few in number but collectively have a worldwide presence.


Asunto(s)
Culicidae/microbiología , Culicidae/virología , Mordeduras y Picaduras de Insectos/inmunología , Modelos Inmunológicos , Neoplasias/microbiología , Neoplasias/virología , Animales , Culicidae/inmunología , Neoplasias/inmunología
14.
J Invest Dermatol ; 99(6): 734-42, 1992 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-1281863

RESUMEN

The growth-associated protein 43 (GAP43) is a neuronal membrane protein involved in axonal growth and regeneration as well as in the modulation of synaptic plasticity. It is present in sensory and sympathetic neurons, where it is consistently associated with the expression of nerve growth factor receptor (NGFr). We investigated, by means of immunohistochemistry, the presence and distribution of the GAP43-immunoreactivity (IR) and of the NGFr-IR in the adult normal human skin from various body regions. In adjacent sections, a comparison with the distribution of the neuronal markers protein gene product 9.5 (PGP 9.5), substance P (SP), and calcitonin gene-related peptide (CGRP) was performed. Our results indicate that in adult human skin 1) a GAP43-IR is morphologically present in epidermal and dermal nerve fibers; 2) a NGFr-IR is associated with neuronal as well as non-neuronal elements of cutaneous nerves; 3) the basal epidermal cell layer expresses a NGFr-IR, which is unevenly distributed according to the different body areas; and 4) there is suggestive evidence for a simultaneous expression of GAP43-, NGFr-, PGP 9.5-, SP-, and CGRP-IR in at least part of the cutaneous nerve fibers. The presence of GAP43-immunoreactive nerve fibers might be a marker of a continuous synaptic remodeling in adult skin, whereas the distribution of the NGFr-IR could be relevant for our understanding of the maintenance of the neuronal-target relationship(s).


Asunto(s)
Glicoproteínas de Membrana/análisis , Proteínas del Tejido Nervioso/análisis , Receptores de Factor de Crecimiento Nervioso/análisis , Piel/ultraestructura , Adulto , Péptido Relacionado con Gen de Calcitonina/análisis , Femenino , Proteína GAP-43 , Humanos , Inmunohistoquímica , Masculino , Glicoproteínas de Membrana/inmunología , Persona de Mediana Edad , Proteínas del Tejido Nervioso/inmunología , Receptores de Factor de Crecimiento Nervioso/inmunología , Piel/química , Sustancia P/análisis , Tioléster Hidrolasas/análisis , Ubiquitina Tiolesterasa
15.
J Invest Dermatol ; 111(1): 114-8, 1998 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-9665396

RESUMEN

The nerve growth factor and its receptor are important in nerve growth, differentiation, maturation, and maintenance. In order to explore the exact distribution of p75 low-affinity nerve growth factor receptor (p75 NGFr) expression in cutaneous nerve fibers, p75 NGFr and neuron-specific enolase double immunofluorescence and immunoelectron microscopic studies were conducted on normal human skin samples. After p75 NGFr and neuron-specific enolase immunofluorescence double staining, the dermal nerves were strongly p75 NGFr-immunoreactive (IR); however, very few p75 NGFr-IR nerve fibers were found in the epidermis. p75 NGFr immunoreactivity was found mainly in the peripheral part of cutaneous nerve trunks and fibers, whereas neuron-specific enolase immunoreactivity was mainly seen within the axons. After ultrastructural immunostaining, the Schwann cell membrane was strongly p75 NGFr-IR. The Schwann cell membrane facing the connective tissue was more strongly p75 NGFr-IR than the part of the membrane close to the axon; the Schwann cell cytoplasm nearest to the membrane sometimes also showed a high p75 NGFr immunoreactivity, whereas the rest of the cytoplasm was generally more weakly p75 NGFr-IR; however, the axon itself seldom showed any such immunoreactivity; actually, only a few parts of the axonal membrane revealed a weak staining, leaving most of the membrane unstained. The axoplasm was not p75 NGFr-IR. The results--that in human cutaneous nerves it is mainly the Schwann cells that express p75 NGFr immunoreactivity--further stress the active role of the glial ensheathment in the control and maintenance of a normal target innervation.


Asunto(s)
Fibras Nerviosas/química , Receptores de Factor de Crecimiento Nervioso/análisis , Piel/inervación , Técnica del Anticuerpo Fluorescente , Humanos , Microscopía Inmunoelectrónica , Fosfopiruvato Hidratasa/análisis , Receptores de Factor de Crecimiento Nervioso/inmunología , Piel/ultraestructura
16.
J Invest Dermatol ; 104(1): 134-7, 1995 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-7798631

RESUMEN

To prove the existence of human intraepidermal nerve fibers at the electron microscopic level, we used both conventional and immunohistochemical ultrastructural techniques. Specimens were obtained from skin of the back, one of the most densely innervated areas of the human epidermis. The immunohistochemical marker protein gene product 9.5 was chosen because it is highly potent in labeling nerves. Thin nerve fibers were found in the basal, spinous, and granular layers of the epidermis with both techniques used, although it was more difficult to identify the nervous structures with the conventional method. The nerves appeared in the intercellular spaces and contacted keratinocyte cell bodies or cilia by membrane-membrane apposition, but without any specialized structures. Nerve fibers in the very superficial part of the vital human epidermis have not been described before at the ultrastructural level.


Asunto(s)
Fibras Nerviosas/ultraestructura , Piel/inervación , Humanos , Microscopía Electrónica , Fibras Nerviosas/química , Orgánulos/química , Piel/química , Tioléster Hidrolasas/análisis , Tioléster Hidrolasas/inmunología , Ubiquitina Tiolesterasa
17.
J Invest Dermatol ; 96(6): 852-6, 1991 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-2045674

RESUMEN

gamma-melanocyte stimulating hormone (gamma-MSH)-like immunoreactivity has been found by indirect immunofluorescence in nerve fibers and terminals as well as in neutrophilic granulocytes of normal human skin. A preferential localization to sensory nerves was seen; abundant nerve fibers displaying gamma-MSH immunoreactivity were observed as free nerve endings in the basal layer of the epidermis and in the upper dermis, close to the Merkel cells, in Meissner's corpuscles, around the external root sheath of the lower part of the hair follicles, and in nerve bundles of the deeper parts of the dermis. Very few fibers were seen to be associated with sweat glands and most blood vessels, although arterioles were densely innervated. Thus, gamma-MSH should be considered for possible role as a sensory or axon-reflex chemical messenger. Furthermore, the presence of gamma-MSH in neutrophilic granulocytes raises the possibility that gamma-MSH may play a role in the genesis of post-inflammatory hyperpigmentation, nevi, and melanomas.


Asunto(s)
Hormonas Estimuladoras de los Melanocitos/análisis , Fibras Nerviosas/química , Neutrófilos/química , Piel/química , Adulto , Secuencia de Aminoácidos , Epidermis/química , Femenino , Técnica del Anticuerpo Fluorescente , Humanos , Masculino , Persona de Mediana Edad , Datos de Secuencia Molecular , Piel/citología , Piel/inervación
18.
J Invest Dermatol ; 111(6): 1010-4, 1998 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-9856809

RESUMEN

Immunohistochemistry was applied in the investigation of the possible existence of serotonin in human skin. It was found that epidermal melanocytes express a serotonin-like immunoreactivity. The immunoreactivity was associated with both the cytoplasm and the cellular membrane, though the latter was only found in certain cells. The serotonin anti-serum labeled the same cells as NKI-beteb, which is known as a reliable marker of melanocytes. Blocking experiments showed that both serotonin and NKI-beteb have different epitopes in the melanocytes. In in vitro studies, serotonin-like immunoreactivity appeared in approximately 90% of cultured human melanocytes, and was found both in the cytoplasm and also in the nuclei. Thus, we believe the melanocytes to be the origin of serotonin (or a serotonin-like molecule) in the skin.


Asunto(s)
Melanocitos/inmunología , Serotonina/inmunología , Piel/citología , Piel/inmunología , Anticuerpos Monoclonales , Especificidad de Anticuerpos , Antígenos de Neoplasias/análisis , Biomarcadores/análisis , Células Cultivadas , Técnica del Anticuerpo Fluorescente Indirecta , Humanos
19.
J Comp Neurol ; 217(3): 264-70, 1983 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-6136532

RESUMEN

Striatal neurons containing both somatostatin- and avian pancreatic polypeptide (APP)-like immunoreactivities have been shown to be selectively stained by the histochemical method for nicotinamide adenine dinucleotide phosphate (NADPH)-diaphorase activity. In the present study, we have utilized this histochemical technique to examine the morphology of these striatal neurons at the light and electron microscopic levels. Our results indicate that the striatal somatostatin/APP/NADPH-diaphorase neurons occur throughout the striatum and have long, aspiny dendrites, oval, invaginated nuclei with prominent nucleoli, and receive few axosomatic contacts. These cells appear to correspond to a population of medium-sized aspiny interneurons reported previously in Golgi and electron microscopic studies of the striatum.


Asunto(s)
Cuerpo Estriado/metabolismo , NADH NADPH Oxidorreductasas/metabolismo , NADPH Deshidrogenasa/metabolismo , Polipéptido Pancreático/metabolismo , Somatostatina/metabolismo , Animales , Cuerpo Estriado/citología , Cuerpo Estriado/ultraestructura , Masculino , Microscopía Electrónica , Ratas , Ratas Endogámicas
20.
J Comp Neurol ; 337(3): 366-85, 1993 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-8282848

RESUMEN

The innervation of the mystacial pad in the rat was investigated with the aid of antihuman protein gene product (PGP) 9.5 immunofluorescence. PGP 9.5 is ubiquitin carboxyl-terminal hydrolase, which is distributed throughout neuronal cytoplasm. This technique revealed all previously known innervation as well as a wide variety of small-caliber axons and some endings of large-caliber afferents that had not been observed before. Newly revealed innervation affiliated with vibrissal-follicle sinus complexes included 1) fine-caliber, radially oriented processes in the epidermal rete ridge collar; 2) a loose network of fine-caliber, circumferentially arrayed processes in the centrifugal part of the mesenchymal sheath at the level of the ring sinus; 3) a loose haphazard network of fine-caliber and medium-caliber processes in the mesenchymal sheath and among the trabeculae of the cavernous sinus; 4) a loose network of circumferentially arrayed processes within the mesenchymal sheath of the cavernous sinus and in close proximity to the basement membrane; 5) a dense network of reticular-like endings provided by large-caliber afferents to the mesenchymal sheath in the upper part of the cavernous sinus; and 6) fine-caliber innervation to the dermal papilla at the base of all vibrissal shafts. In the intervibrissal skin, a dense distribution of fine-caliber individual and clustered profiles was detected in the epidermis. In addition to previously known innervation, Merkel endings were consistently observed in the epidermis at the mouths of guard hairs, loose networks of fine-caliber axons were found around the necks of occasional guard hairs, and fine-caliber profiles were frequently affiliated with vellus hairs. Vascular profiles were heavily innervated throughout the dermis. Axons and motor end plates of the facial nerve innervation to papillary muscles also were labeled. Transection of the infraorbital nerve eliminated all but the facial nerve innervation. Unilateral removal of the superior cervical ganglion eliminated the innervation to the dermal papillae but caused no other noticeable reduction. PGP 9.5-like immunofluorescence was also moderately expressed in apparent Schwann cells, in Merkel cells only in the external root sheath of vibrissal follicles, and in apparent dendritic and/or Langerhans cells usually located in the epidermis and occasionally in the follicles. PGP 9.5-like immunofluorescence persisted in highly vacuolated profiles along the usual courses of medium to large-caliber axons 2 weeks after nerve transection. The possible functional role of the newly discovered innervation is considered along with that of previously identified afferents.


Asunto(s)
Tioléster Hidrolasas/análisis , Vibrisas/inervación , Animales , Axones/fisiología , Epidermis/inervación , Epidermis/fisiología , Femenino , Técnica del Anticuerpo Fluorescente , Cabello/fisiología , Terminaciones Nerviosas/inmunología , Terminaciones Nerviosas/metabolismo , Neuronas Aferentes/fisiología , Ratas , Ratas Sprague-Dawley , Sistema Nervioso Simpático/citología , Sistema Nervioso Simpático/fisiología , Ubiquitina Tiolesterasa
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