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1.
Sci Rep ; 10(1): 2926, 2020 02 19.
Artículo en Inglés | MEDLINE | ID: mdl-32076042

RESUMEN

In animal models of inflammation and in farm animals, dietary inclusion of spray-dried porcine plasma (SDP) reduces mucosal inflammation. Here, we study whether these effects could be mediated by changes in the intestinal microbiota and if these changes are similar to those induced by oral antibiotics. Weaned 21-day-old C57BL/6 mice were divided into 3 groups: the CTL group, fed the control diet; the COL group, administered low doses of neomycin and colistin; and the SDP group, supplemented with 8% SDP. After 14 days, analysis of the fecal microbiome showed that the microbiota profiles induced by SDP and the antibiotics were very different, thus, SDP has prebiotic rather than antibiotic effects. At the phylum level, SDP stimulated the presence of Firmicutes, considerably increasing the lactobacilli population. It also enhanced the growth of species involved in regulatory T-lymphocyte homeostasis and restoration of the mucosal barrier, as well as species negatively correlated with expression of pro-inflammatory cytokines. At the mucosal level, expression of toll-like receptors Tlr2, Tlr4 and Tlr9, and mucous-related genes Muc2 and Tff3 with regulatory and barrier stability functions, were increased. SDP also increased expression of Il-10 and Tgf-ß, as well as markers of macrophages and dendritic cells eventually promoting an immune-tolerant environment.


Asunto(s)
Suplementos Dietéticos , Microbioma Gastrointestinal , Plasma/metabolismo , Prebióticos , Animales , Antibacterianos/farmacología , Bacterias/efectos de los fármacos , Desecación , Heces/microbiología , Microbioma Gastrointestinal/efectos de los fármacos , Mucosa Intestinal/efectos de los fármacos , Mucosa Intestinal/inmunología , Masculino , Ratones Endogámicos C57BL , Filogenia , Análisis de Componente Principal , Porcinos
2.
Med Mal Infect ; 49(8): 602-606, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31088756

RESUMEN

OBJECTIVE: Japanese encephalitis (JE) is a rare but severe disease. It is a potential threat for people traveling to endemic areas. The risk of developing JE is low (<1%), but the associated case fatality is high (30%). There is no specific treatment for JE, but a vaccine is available. We performed an observational survey to assess practices of French health professionals regarding JE vaccination. METHODS: Standardized questionnaires were sent by email to a sample of French health professionals practicing in vaccination centers. Participation was on a voluntary and anonymous basis. The questionnaires requested socio-demographic details, and included multiple choice questions. RESULTS: The response rate was 38.5%. Most participating health professionals had been working for more than three years in a vaccination center and declared not to be reluctant to perform JE vaccination. Reluctance was mostly based on the vaccine cost and on the difficulty to properly assess the risk for patients. The rapid protocol was largely preferred except in the overseas regions (P<0.05, Fisher's exact test). Traveling to South Asia and backpacking were considered at-risk conditions. Participants proposed the vaccination all year round. Most participants would not have proposed the JE vaccination for the concrete case outlined in the questionnaire. CONCLUSIONS: French health professionals are globally favorable to JE vaccination. However, assessing the risk of exposure is difficult in routine practice.


Asunto(s)
Encefalitis Japonesa/prevención & control , Vacunas contra la Encefalitis Japonesa , Pautas de la Práctica en Medicina , Vacunación/normas , Adulto , Femenino , Francia , Encuestas de Atención de la Salud , Personal de Salud , Humanos , Masculino , Persona de Mediana Edad
3.
Rev Esp Cir Ortop Traumatol ; 60(6): 346-354, 2016.
Artículo en Inglés, Español | MEDLINE | ID: mdl-27546866

RESUMEN

BACKGROUND: Bone loss in the distal femur is a common problem in knee revision surgeries. The problem is exacerbated in the context of an active infection. In extreme cases this bone loss could compromise the feasibility of a two-stage exchange protocol using dynamic spacers due to the inherent instability of this type of spacers. Use of a hip prefabricated spacer in a "reverse" way forming a ball-and- socket joint is a therapeutic option in cases of massive bone defect and infection. MATERIAL AND METHODS: A retrospective review was performed of our institutional database to identify all cases of massive distal femoral defect in which this technique was used from January 2010 to December 2013. A record was made of the epidemiological data, characteristics of the infection (clinical and microbiological), and adverse event during the spacer stage. The main end-point was the infection eradication rate (minimum: 18 months of follow-up). The complications associated with the technique were also assessed. Finally, each patient completed a visual analogue pain scale, and a satisfaction questionnaire (SAPS). RESULTS: This technique was successfully used in six cases so far, controlling the infection in all cases. Mean femoral defect was 117cm (range: 32-191cm). Mean time with spacer was 7.6 months, with no major complications. All but one patient reached second stage reconstruction with a mega-prosthesis, and mean time since second stage was 34.7 months. All patients stated high levels of satisfaction with the technique employed, as well as and low pain scores (mean visual analogue pain scale: 1; range: 0-4). CONCLUSION: A reproducible and safe technique is described. Patients report a high level of satisfaction with the procedure, and there were no cases of recurrence of the infection after a minimum follow-up of 18 months.


Asunto(s)
Artroplastia de Reemplazo de Rodilla/instrumentación , Infecciones por Escherichia coli/cirugía , Fémur/patología , Prótesis de la Rodilla/efectos adversos , Infecciones Relacionadas con Prótesis/cirugía , Reoperación/instrumentación , Infecciones Estafilocócicas/cirugía , Anciano , Anciano de 80 o más Años , Artroplastia de Reemplazo de Rodilla/métodos , Infecciones por Escherichia coli/patología , Femenino , Fémur/cirugía , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Infecciones Relacionadas con Prótesis/patología , Reoperación/métodos , Estudios Retrospectivos , Infecciones Estafilocócicas/patología , Resultado del Tratamiento
4.
Arch Orthop Trauma Surg ; 132(5): 719-24, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-22258179

RESUMEN

This technical note describes an intraoperatively custom-made, antibiotic-loaded bone cement roof, used in conjunction with a prefabricated hip spacer to improve component stability, as part of the first stage of a two-stage procedure for an infected hip implant. This technique was successfully used in seven cases who presented with extensive superior and/or posterio-superior acetabular defect, which created a risk of spacer dislocation. With this technique we were able to avoid any further dislocation in these seven cases. We believe that the technique may reduce postoperative spacer dislocation in cases with extensive acetabular defects, while improving clinical outcomes.


Asunto(s)
Antibacterianos/administración & dosificación , Artroplastia de Reemplazo de Cadera , Cementos para Huesos , Infecciones Relacionadas con Prótesis/cirugía , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Infecciones Relacionadas con Prótesis/diagnóstico , Infecciones Relacionadas con Prótesis/patología , Reoperación
5.
Rev Esp Enferm Dig ; 102(11): 631-6, 2010 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21142383

RESUMEN

INTRODUCTION: Pancreatic cancer presents the worst survival rates of all neoplasms. Surgical resection is the only potentially curative treatment, but is associated with high complication rates and outcome is bad even in those resected cases. Therefore, candidates amenable for resection must be carefully selected. Identification of prognostic factors preoperatively may help to improve the treatment of these patients, focusing on individually management based on the expected response. PATIENTS AND METHODS: We perform a retrospective study of 59 patients with histological diagnosis of pancreatic carcinoma between 1999 and 2003, looking for possible prognostic factors. RESULTS: We analyze 59 patients, 32 males and 27 females with a mean age of 63.8 years. All the patients were operated, performing palliative surgery in 32% and tumoral resection in 68%, including pancreaticoduodenectomies in 51% and distal pancreatectomy in 17%. Median global survival was 14 months (Range 1-110).We observed that preoperative levels of hemoglobin under 12 g/dl (p = 0.0006) and serum albumina under 2.8 g/dl (p = 0.021) are associated with worse survival. CONCLUSION: Preoperative levels of hemoglobin and serum albumina may be prognostic indicators in pancreatic cancer.


Asunto(s)
Hemoglobinas/análisis , Neoplasias Pancreáticas/sangre , Neoplasias Pancreáticas/mortalidad , Albúmina Sérica/análisis , Femenino , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Cuidados Preoperatorios , Pronóstico , Estudios Retrospectivos , Tasa de Supervivencia
6.
Med Oral Patol Oral Cir Bucal ; 11(2): E206-9, 2006 Mar 01.
Artículo en Inglés, Español | MEDLINE | ID: mdl-16505803

RESUMEN

Basal cell adenoma of the salivary glands is an uncommon type of monomorphous adenoma. Its most frequent location is the parotid gland. It usually appears as a firm and mobile slow-growing mass. Histologically, isomorphic cells in nests and interlaced trabecules with a prominent basal membrane are observed. It is also characterized by the presence of a slack and hyaline stroma and the absence of myxoid or condroid stroma. In contrast to pleomorphic adenoma, it tends to be multiple and its recurrence rate after surgical excision is high. Due to prognostic implications, differential diagnosis with basal cell adenocarcinoma, adenoid cystic carcinoma and basaloid squamous cell carcinoma is mandatory. We describe a case of basal cell adenoma of the parotid gland. We also review the literature and discuss the diagnosis and management of this rare entity.


Asunto(s)
Adenoma/patología , Neoplasias de la Parótida/patología , Adulto , Femenino , Humanos
7.
J Membr Biol ; 206(1): 43-51, 2005 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16440180

RESUMEN

Fluid and electrolyte absorption by colonic crypts depends on the transport properties of crypt cellular and paracellular routes and of the pericryptal sheath. As a low-Na(+) diet increases aldosterone and angiotensin II secretion, either hormone could affect absorption. Control and adrenalectomized (ADX) Sprague-Dawley rats were kept at a high-NaCl (HS) diet and then switched to low-NaCl (LS) diet for 3 days. Aldosterone or angiotensin II plasma concentrations were maintained using implanted osmotic mini-pumps. The extracellular Na(+) concentration in isolated rat distal colonic mucosa was determined by confocal microscopy using a low-affinity Na(+) -sensitive fluorescent dye (Sodium red, and Na(+) -insensitive BODIPY) bound to polystyrene beads. Crypt permeability to FITC-labelled dextran (10 kDa) was monitored by its rate of escape from the crypt lumen into the pericryptal space. Mucosal ion permeability was estimated by transepithelial electrical resistance (TER) and amiloride-sensitive short-circuit current (SCC). The epithelial Na(+) channel, ENaC, was determined by immunolocalization. LS diet decreased crypt wall permeability to dextran by 10-fold and doubled TER. Following ADX, aldosterone decreased crypt wall dextran permeability, increased TER, increased Na(+) accumulation in the pericryptal sheath and ENaC expression even in HS. Infusion of angiotensin II to ADX rats did not reverse the effects of aldosterone deprivation. These findings indicate that aldosterone alone is responsible for both the increase in Na(+) absorption and the decreased paracellular and pericryptal sheath permeability.


Asunto(s)
Aldosterona/metabolismo , Angiotensina II/metabolismo , Colon/metabolismo , Dieta Hiposódica/métodos , Absorción Intestinal/fisiología , Sodio en la Dieta/metabolismo , Adaptación Fisiológica/fisiología , Animales , Masculino , Permeabilidad , Ratas , Ratas Sprague-Dawley
8.
J Membr Biol ; 206(1): 53-9, 2005 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16440181

RESUMEN

Pericryptal myofibroblast growth in descending colonic crypts correlates with the activation of the renin-angiotensin-aldosterone system. Earlier work showed that during the transition from a high-Na(+) (HS) to low-Na(+) (LS) diet there are changes in the colonic crypt wall and pericryptal sheath. As LS diet increases both aldosterone and angiotensin II, the aim here was to determine their individual contributions to the trophic changes in colonic crypts. Experiments were conducted on control and adrenalectomized Sprague-Dawley rats fed an HS diet and then switched to LS diet for 3 days and supplemented with aldosterone or angiotensin II. The actions of the angiotensin-converting enzyme inhibitor captopril, the angiotensin receptor antagonist losartan and the aldosterone antagonist spironolactone on extracellular matrix proteins, claudin 4 and E-cadherin myofibroblast proteins, alpha-smooth muscle actin (alpha-SMA) and OB-cadherin (cadherin 11), angiotensin type 1 and TGFbetar1 membrane receptors were determined by immunolocalization in fixed distal colonic mucosa. The LS diet or aldosterone supplementation following ADX in HS or LS increased extracellular matrix, membrane receptors and myofibroblast proteins, but angiotensin alone had no trophic effect on alpha-SMA. These results show that aldosterone stimulates myofibroblast growth in the distal colon independently of dietary Na(+) intake and of angiotensin levels. This stimulus could be a genomic response or secondary to stretch of the pericryptal sheath myofibroblasts accompanying enhanced rates of crypt fluid absorption.


Asunto(s)
Aldosterona/metabolismo , Angiotensina II/metabolismo , Colon Descendente/metabolismo , Dieta Hiposódica/métodos , Miocitos del Músculo Liso/fisiología , Sodio en la Dieta/metabolismo , Adaptación Fisiológica/fisiología , Animales , Colon Descendente/citología , Absorción Intestinal/fisiología , Masculino , Miocitos del Músculo Liso/citología , Permeabilidad , Ratas , Ratas Sprague-Dawley
9.
Eur J Neurosci ; 17(11): 2457-61, 2003 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-12814377

RESUMEN

The role of the piriform cortex (PC) in olfactory information processing remains mainly unknown. Indeed, until recently, only a few studies have investigated the response of PC neurons to odours and these studies did not take into account the functional heterogeneity of the PC previously described using an electrical stimulation paradigm. In this experiment, extracellular activity in response to odour was recorded in urethane anaesthetized rats in the different parts of the cortex ranging from anterior to posterior. A large percentage of cortical cells were silent at rest, and this percentage increased from anterior to posterior. Analysis of odour evoked activity revealed a large percentage of nonresponsive cells that increased from anterior to posterior. Cell activity was largely synchronized with breathing and different temporal patterns were observed. The anterior PC was characterized by odour-evoked responses phase-locked with the inhalation-exhalation transition period. By contrast, activity in the posterior PC was mainly phase-locked with inhalation or exhalation. These data confirm the spatial functional heterogeneity previously reported in the PC. Functional anatomy of the PC suggests that activity in the anterior PC can be mainly driven by afferent activity coming from the OB whereas posterior cells were certainly entrained by more complex mechanisms.


Asunto(s)
Neuronas/fisiología , Odorantes , Vías Olfatorias/fisiología , Animales , Estimulación Eléctrica , Electrofisiología/métodos , Potenciales Evocados/fisiología , Masculino , Inhibición Neural , Vías Nerviosas , Bulbo Olfatorio/fisiología , Vías Olfatorias/anatomía & histología , Neuronas Receptoras Olfatorias , Ratas , Ratas Wistar , Respiración
10.
Bull Soc Pathol Exot ; 95(2): 66-70, 2002 Jun.
Artículo en Francés | MEDLINE | ID: mdl-12145959

RESUMEN

The aims of this paper were to assess resistance of Helicobacter pylori to antibiotics included in the so-called French triple regimens and to identify the possible causes of therapeutic failure in Reunion island. Antibiotic resistance was determined for 109 strains. All the strains were sensitive to amoxicillin and tetracycline, 93.6% were sensitive to ciprofloxacin, 92.7% to erythromycin and 60.6% to metronidazole. Fifty three patients who had previously tested positive for H. pylori received for one week regimen of amoxicillin (1 g bd), clarithromycin (0.5 g bd) and omeprazole (20 mg bd). Eradication rate after therapy was of 73.6%. Therapeutic failure was analysed for 9 patients using random amplified polymorphic DNA and the presence or not of antibiotic resistance. One cause of failure is clarithromycin resistance. These data show that triple therapy can be used in Reunion Island. In case of failure, sensitivity must be detected because the rate of resistance to metronidazole is over 30%.


Asunto(s)
Antibacterianos/uso terapéutico , Infecciones por Helicobacter/tratamiento farmacológico , Helicobacter pylori/efectos de los fármacos , Úlcera Gástrica/microbiología , Amoxicilina/uso terapéutico , Antiulcerosos/uso terapéutico , Distribución de Chi-Cuadrado , Ciprofloxacina/uso terapéutico , Claritromicina/uso terapéutico , Intervalos de Confianza , ADN Bacteriano/análisis , Farmacorresistencia Bacteriana/genética , Eritromicina/uso terapéutico , Femenino , Helicobacter pylori/genética , Humanos , Masculino , Metronidazol/uso terapéutico , Persona de Mediana Edad , Omeprazol/uso terapéutico , Penicilinas/uso terapéutico , Técnica del ADN Polimorfo Amplificado Aleatorio , Reunión , Úlcera Gástrica/tratamiento farmacológico , Tetraciclina/uso terapéutico , Insuficiencia del Tratamiento
11.
Poult Sci ; 78(8): 1126-31, 1999 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10472838

RESUMEN

Transmural potential difference (PD), short-circuit current (Isc), and electrical resistance (R) were measured in the isolated mucosa of the duodenum, jejunum, ileum, proximal cecum, and rectum in order to characterize the electrical properties of the chicken small and large intestine. The chicken intestine was classified into three categories, regarding its electrical characteristics: 1) the duodenum, with four to five times higher R than the other segments and the lowest PD; 2) the group formed by the jejunum, the ileum, and the proximal cecum, with high PD and low R; 3) the rectum, with low PD and low R. In all segments, the addition of D-glucose into the luminal side stimulates Isc, and this effect can be reversed by phloridzin, indicating that the glucose-induced Isc increase is due to Na+-D-glucose co-transport. The effect of glucose is maximal in the rectum, with a fivefold Isc increase, suggesting that this segment may have an important role in the absorption of Na+ as well as of nutrients co-transported with Na+.


Asunto(s)
Pollos/fisiología , Fenómenos Fisiológicos del Sistema Digestivo , Glucosa/metabolismo , Mucosa Intestinal/fisiología , Animales , Impedancia Eléctrica , Glucosa/farmacología , Masculino , Canales de Sodio/fisiología
12.
An Med Interna ; 16(6): 301-4, 1999 Jun.
Artículo en Español | MEDLINE | ID: mdl-10422301

RESUMEN

Necrotizing Histiocytic Lymphadenitis or Kikuchi-Fujimoto disease is a benign process of lymphatic system that consists of lymphadenopathy which may be accompanied by fever, rash and some haematological alterations as anaemia. It affects usually young people, mostly women. Although it is more frequent in Oriental countries, there have been some notices about this disease in Europe recently. We present six patients that have been diagnosed in our Hospital between 1986 and 1996. All presented as cervical masses and fever. The diagnostic procedure was the lymph node biopsy, which showed the typical pathology of this disease: some foci of necrosis which contained plasmocytoides cells and atypical lymphocytes. It is also suggestive of this entity the absence of polymorphonuclear cells. Then, the diagnosis of the Necrotizing Histiocytic Lymphadenitis is made by the histology. The treatment is symptomatic. In all cases the evolution is the whole remission of symptoms. In our patients the illness was self-limited and none presented any other symptom. Our proposal with this article is to remind the clinicians of this entity when people ask for cervical masses and fever.


Asunto(s)
Linfadenitis Necrotizante Histiocítica , Adolescente , Adulto , Biopsia , Femenino , Linfadenitis Necrotizante Histiocítica/diagnóstico , Linfadenitis Necrotizante Histiocítica/patología , Humanos , Ganglios Linfáticos/patología , Masculino
13.
Rev Esp Cardiol ; 52(1): 13-20, 1999 Jan.
Artículo en Español | MEDLINE | ID: mdl-9989132

RESUMEN

We presented the first report of the national database of heart tumors. We described the origin, development and goals reached during the years 1996 and 1997, the way the data was collected and the form used. The cases collected until 31st of December of 1997 include 165 tumors in 155 patients distributed all around the country. Age and gender distribution, way of diagnosis, morphologic classification, treatment and follow-up of this pathology is reported.


Asunto(s)
Neoplasias Cardíacas/epidemiología , Sistema de Registros/estadística & datos numéricos , Adolescente , Adulto , Distribución por Edad , Anciano , Anciano de 80 o más Años , Cardiología , Causas de Muerte , Niño , Preescolar , Femenino , Humanos , Lactante , Masculino , Persona de Mediana Edad , Distribución por Sexo , Sociedades Médicas , España/epidemiología
14.
Neurochirurgie ; 44(4): 278-82, 1998 Nov.
Artículo en Francés | MEDLINE | ID: mdl-9864701

RESUMEN

We report a case of intra-orbital Dacryops in a 7-year-old child. The presenting sign was progressive exophtalmus. The patient was operated via a lateral approach allowing total removal of the cyst without recurrence after one year. The clinical, radiological (CT Scan and MRI) and therapeutical aspects are discussed.


Asunto(s)
Quistes/cirugía , Enfermedades del Aparato Lagrimal/cirugía , Enfermedades Orbitales/cirugía , Niño , Quistes/diagnóstico , Humanos , Enfermedades del Aparato Lagrimal/diagnóstico , Imagen por Resonancia Magnética , Masculino , Enfermedades Orbitales/diagnóstico , Tomografía Computarizada por Rayos X
15.
J Neurophysiol ; 80(5): 2718-26, 1998 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-9819276

RESUMEN

The origin of plateau action potentials was studied in short-term cultures of dorsal paired median (DPM) neurons dissociated from the terminal abdominal ganglion of the cockroach, Periplaneta americana. Spontaneous plateau action potentials were recorded by intracellular microelectrodes in cell bodies that had neurite stumps. These action potentials featured a fast initial depolarization followed by a plateau. However, only fast spikes of short duration were observed when the cell was hyperpolarized from the resting membrane potential. These two different components of the action potentials could be separated by applying depolarizing current pulses from a hyperpolarized holding potential. Application of 200 nM tetrodotoxin (TTX) abolished both fast and slow phases, but depolarization to the original resting potential by steady current injection triggered slow monophasic action potentials that could be blocked by 3 mM CoCl2. In contrast, DPM neurons without neurites were not spontaneously active. In these cells, calcium-dependent slow monophasic action potentials were only recorded immediately after impalement or with current pulse stimulation. Immunocytochemical observations showed that dorsal unpaired median (DUM) neuron cell bodies, which are known to exhibit spontaneous sodium-dependent action potentials, reacted with an antibody directed against a synthetic peptide corresponding to the SP19 segment of voltage-activated sodium channels. In contrast, the antibody did not stain DPM neuron cell bodies but gave intense, patchy staining only in the neurite. Whole cell patch-clamp experiments performed on isolated DPM neuron cell bodies without a neurite revealed the presence of an inward current that did not inactivate completly within the duration of the test pulse. This current was insensitive to both 100 nM TTX and sodium-free saline. It was defined as a high-voltage-activated calcium current according to its high threshold of activation (-30 mV) and its sensitivity to 1 mM CdCl2 and 100 nM omega-conotoxin GVIA. Our findings demonstrate that spontaneous sodium-dependent spikes arising from the neurite are required to initiate slow somatic calcium-dependent action potentials in DPM neurons.


Asunto(s)
Calcio/fisiología , Ganglios de Invertebrados/fisiología , Neuronas/fisiología , Potenciales de Acción/fisiología , Animales , Canales de Calcio/fisiología , Ganglios de Invertebrados/citología , Ganglios de Invertebrados/metabolismo , Ganglios de Invertebrados/ultraestructura , Inmunohistoquímica , Técnicas In Vitro , Membranas Intracelulares/metabolismo , Masculino , Microelectrodos , Neuritas/metabolismo , Neuritas/fisiología , Neuritas/ultraestructura , Neuronas/metabolismo , Neuronas/ultraestructura , Técnicas de Placa-Clamp , Periplaneta , Canales de Sodio/metabolismo
16.
J Insect Physiol ; 43(12): 1125-1131, 1997 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-12770485

RESUMEN

Activation of gamma-aminobutyric acid (GABA) receptors in insect dorsal paired median (DPM) neurons induced two types of response which appeared to be mediated by two different GABA receptor subtypes. When activated by bath application of GABA, one receptor subtype, insensitive to picrotoxin (PTX), mediated a drastic reduction in the firing frequency, leading to a blockade of the spontaneous electrical activity. These effects were accompanied by decreases in the amplitude and duration of the plateau action potential (AP) and the spike after-hyperpolarization (AHP). In most cases, a slight depolarization of the resting membrane potential occurred. Bath application of the vertebrate GABA(B) receptor agonists 3-aminopropyl(methyl)phosphinic acid (SKF 97541) and 3-aminopropylphosphinic acid (CGA 147823/CGP 27492) induced similar responses. Another GABA receptor subtype, less sensitive to GABA, mediated a chloride dependent hyperpolarization that was suppressed by bath application of PTX. The approximate locations of these two GABA receptor subtypes were determined by local pressure microapplications of GABA and vertebrate GABAergic agonists. The PTX-sensitive receptors were located predominantly on the surface of the ganglion where the apical pole of the soma is situated, while the PTX-resistant receptors appeared to be located deeper within the ganglion.These results reveal the existence of two GABA receptor subtypes on the DPM neurons and provide evidence for a functional role for PTX-resistant GABA receptors in the regulation of spontaneous firing.

17.
Neurosci Res ; 29(3): 263-8, 1997 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-9436652

RESUMEN

The proctolinergic nature of dorsal paired median (DPM) neurons generating plateau action potentials (PAPs) of the cockroach CNS has been demonstrated using a double labelling technique (lucifer yellow staining and proctolin-like immunochemistry). Electrophysiological results support morphological evidence that a direct pathway exists from axons passing throughout the proctodeal nerves to electrically active DPM neuron somata. However, the occurrence of spike failure along the neuritic membrane and the existence of a neuritic spike initiating site has been postulated because spontaneous PAPs recorded intracellularly were not associated on a one-to-one basis with peripheral axon spikes.


Asunto(s)
Neuronas/fisiología , Neuropéptidos , Neurotransmisores/análisis , Oligopéptidos/análisis , Periplaneta/fisiología , Potenciales de Acción , Animales , Axones/fisiología , Axones/ultraestructura , Electrofisiología/métodos , Colorantes Fluorescentes , Inmunohistoquímica/métodos , Isoquinolinas , Masculino , Neuritas/fisiología , Neuronas/citología
18.
Am J Physiol ; 271(4 Pt 2): R1085-9, 1996 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-8898004

RESUMEN

The kinetic parameters of hexose uptake by the small and large intestine of the chicken have been determined in vitro. Rates of initial influx of alpha-methyl-D-glucoside and L-glucose were measured in everted sleeves of the duodenum, jejunum, ileum, proximal cecum, and rectum. Results show the following. 1) Maximal transport capacity values for alpha-methyl-D-glucoside show that the jejunum is the segment that is best suited for Na(+)-mediated uptake. 2) The calculated apparent Michaelis constant values were (in mmol/l) 11.6 for duodenum, 7.8 for jejunum, 3.5 for ileum, 2.4 for proximal cecum, and 7.1 for rectum. This suggests that, with the exception of the rectum, the affinity of the carrier for alpha-methyl-D-glucoside progressively increases in the distal direction. 3) Diffusion constant values indicate that influx of hexoses by a passive mechanism in the duodenum and proximal cecum is significantly higher than in the other segments. 4) The sum of passive and mediated mechanisms confers to the duodenum and jejunum a high capacity to absorb hexoses. The ileum, proximal cecum, and rectum have a quantitatively minor role, albeit significant, in completing the absorptive function.


Asunto(s)
Pollos/metabolismo , Hexosas/farmacocinética , Intestino Grueso/metabolismo , Intestino Delgado/metabolismo , Animales , Carbohidratos/farmacocinética , Glucosa/farmacocinética , Absorción Intestinal , Masculino , Metilglucósidos/farmacocinética
19.
Neurochirurgie ; 42(2): 95-9, 1996.
Artículo en Francés | MEDLINE | ID: mdl-8952903

RESUMEN

We present a case of brain abscess caused by Cladosporium trichoides which reappeared fifteen months later, in spite of a surgical procedure and antifungal chemotherapy. The importance of a complete neurosurgical resection of the lesion which determines the prognosis is emphasized. Based on amphotericine B, flucytosine, and itraconazole, the antifungal treatment is not fully standardized. Regular clinical and CT scan controls are necessary because of frequent recurrence.


Asunto(s)
Absceso Encefálico/etiología , Cromoblastomicosis/complicaciones , Absceso Encefálico/diagnóstico por imagen , Absceso Encefálico/cirugía , Humanos , Masculino , Persona de Mediana Edad , Seudotumor Cerebral/etiología , Recurrencia , Tomografía Computarizada por Rayos X
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