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1.
J Eur Acad Dermatol Venereol ; 34(8): 1715-1721, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31838771

RESUMEN

BACKGROUND: Extramammary Paget's disease (EMPD) is a rare malignant skin cancer. One of the hallmarks of cancers, including EMPD, is an enhancement of aerobic glycolysis, which is also known as the Warburg effect. In the last step of glycolysis, the enzyme lactate dehydrogenase A (LDHA) catalyzes the conversion of pyruvate to lactic acid, the accumulation of which contributes to the creation of an acidic tumour microenvironment. This in turn results in immunosuppression in various types of cancers. However, the contribution of these pathways has not been well-studied in EMPD. OBJECTIVE: To investigate the significance of the Warburg effect and its contribution to the tumour immune microenvironment in EMPD. METHODS: The mRNA expression levels of molecules involved in glycolysis and immune-related cytokines were examined by ddPCR. The number of immune cells was assessed by immunohistochemistry (IHC). RESULTS: The levels of two glycolytic enzymes, HK2 and LDHA, in tumour tissues were significantly increased compared to those in paired-normal tissues. IHC analyses revealed increased numbers of PD-L1+ , PD-1+ , CD163+ M2 macrophages, Iba1+ macrophages and Foxp3+ Tregs that were associated with high LDHA levels in EMPD. ddPCR demonstrated that multiple cytokines including IL-4, IL-6, IL-10, TGF-ß and CCL-2 were upregulated and associated with high LDHA levels in EMPD. Statistical analyses showed that IL-6 mRNA expression correlated with the number of CD163+ , Iba-1+ and Foxp3+ cells. CONCLUSION: The Warburg effect contributes to immunomodulation in the tumour microenvironment and further elucidation may lead to better understanding of the pathogenesis of EMPD.


Asunto(s)
L-Lactato Deshidrogenasa/genética , Enfermedad de Paget Extramamaria/inmunología , Microambiente Tumoral , Humanos , Inmunohistoquímica , Enfermedad de Paget Extramamaria/genética
2.
Br J Dermatol ; 181(3): 505-511, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-30706452

RESUMEN

BACKGROUND: Although carcinoembryonic antigen (CEA) and cytokeratin 19 fragment (CYFRA) are useful markers for extramammary Paget disease (EMPD), serum CEA and CYFRA levels are not elevated in most patients with EMPD without metastasis. Cell-free (cf)DNA has attracted attention as an indicator of clinical conditions in several cancers. OBJECTIVES: To identify further useful biomarkers for the detection of EMPD, including early lesions, and to study the clinical implications of cfDNA in EMPD. METHODS: cfDNA were isolated from serum of patients with EMPD with and without metastasis, and from healthy volunteers. Serum extracts were amplified using polymerase chain reaction. RESULTS: Serum cfDNA levels were significantly elevated in patients with EMPD with or without metastasis compared with those in healthy controls. Serum cfDNA was a better diagnostic marker for the presence of EMPD than serum CYFRA. Moreover, the postoperative serum cfDNA levels were significantly lower than those from the preoperative samples, and the change in serum cfDNA levels reflected the clinical courses of patients with EMPD treated with chemotherapy. CONCLUSIONS: Taking the evidence together, serum cfDNA levels may be a useful marker for diagnosis and disease progression in EMPD. What's already known about this topic? Serum levels of carcinoembryonic antigen (CEA) and cytokeratin 19 fragment (CYFRA) are not elevated in most patients with extramammary Paget disease (EMPD) without metastasis. Cell-free (cf)DNA has attracted attention as an indicator of clinical conditions in several cancers. There are few reports of the clinical implications of cfDNA in dermatology. What does this study add? Serum cfDNA levels were significantly elevated in patients with EMPD with or without metastasis compared with those in healthy controls. Postoperative serum cfDNA levels were significantly lower than those from the preoperative samples. Changes in serum cfDNA levels reflected the clinical courses of patients with EMPD treated with chemotherapy. What is the translational message? Serum cfDNA levels in patients with EMPD are a useful marker for the detection of EMPD, including localized EMPD. Changes in serum cfDNA levels in an individual patient may reflect the clinical course of EMPD.


Asunto(s)
Biomarcadores de Tumor/sangre , Ácidos Nucleicos Libres de Células/sangre , Enfermedad de Paget Extramamaria/diagnóstico , Neoplasias Cutáneas/diagnóstico , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Antígenos de Neoplasias/sangre , Biomarcadores de Tumor/genética , Estudios de Casos y Controles , Progresión de la Enfermedad , Femenino , Humanos , Queratina-19/sangre , Masculino , Persona de Mediana Edad , Enfermedad de Paget Extramamaria/sangre , Enfermedad de Paget Extramamaria/genética , Enfermedad de Paget Extramamaria/cirugía , Periodo Posoperatorio , Periodo Preoperatorio , Piel/patología , Neoplasias Cutáneas/sangre , Neoplasias Cutáneas/genética , Neoplasias Cutáneas/cirugía , Adulto Joven
7.
Skin Health Dis ; 1(3): e37, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35663139

RESUMEN

Background: Deficiency of DNA mismatch repair (MMR) induces microsatellite instability (MSI). Pembrolizumab, an antibody targeting PD-1 (an immune checkpoint inhibitor), is more effective against MMR-deficient tumours than against MMR-proficient tumours. The status of MMR is a useful biomarker for predicting the effectiveness of pembrolizumab administration. Although the status of MMR has attracted attention in skin tumours, there are few reports on MSI in extramammary Paget's disease (EMPD). Objectives: To evaluate the status of MMR in patients with EMPD. Materials & Methods: One hundred one patients with EMPD were included. MMR status of the genomic DNA of each subject was analysed using Promega panel (approved as a companion diagnostic agent for the administration of pembrolizumab). Results: MSI testing showed the occurrence rates of MSI-high (more than two markers are unstable), MSI-low (one marker is unstable) and MSS (all markers are stable) tumour tissues were 0% (0/101), 1.0% (1/101) and 99.0% (100/101), respectively. Conclusion: The status of MMR may not be useful for the potential therapeutic application of pembrolizumab.

8.
J Neurosci ; 20(24): 9242-51, 2000 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-11125002

RESUMEN

Although nitrous oxide (N(2)O) has been used to facilitate surgery for >150 years, its molecular mechanism of action is not yet defined. Having established that N(2)O-induced release of norepinephrine mediates the analgesic action at alpha(2) adrenoceptors in the spinal cord, we now investigated whether activation of noradrenergic nuclei in the brainstem is responsible for this analgesic action and which alpha(2) adrenoceptor subtype mediates this property. In rats, Fos immunoreactivity was examined in brainstem noradrenergic nuclei after exposure to nitrous oxide. After selective lesioning of noradrenergic nuclei by intracerebroventricular application of the mitochondrial toxin saporin, coupled to the antibody directed against dopamine beta hydroxylase (DbetaH-saporin), the analgesic and sedative actions of N(2)O were determined. Null mice for each of the three alpha(2) adrenoceptor subtypes (alpha(2A), alpha(2B), and alpha(2C)), and their wild-type cohorts, were tested for their antinociceptive and sedative response to N(2)O. Exposure to N(2)O increased expression of Fos immunoreactivity in each of the pontine noradrenergic nuclei (A5, locus coeruleus, and A7). DbetaH-saporin treatment eliminated nearly all of the catecholamine-containing neurons in the pons and blocked the analgesic but not the sedative effects of N(2)O. Null mice for the alpha(2B) adrenoceptor subtype exhibited a reduced or absent analgesic response to N(2)O, but their sedative response to N(2)O was intact. Our results support a pivotal role for noradrenergic pontine nuclei and alpha(2B) adrenoceptors in the analgesic, but not the sedative effects of N(2)O. Previously we demonstrated that the analgesic actions of alpha(2) adrenoceptor agonists are mediated by the alpha(2A) subtype; taken together with these data we propose that exogenous and endogenous alpha(2) adrenoceptor ligands activate different alpha(2) adrenoceptor subtypes to produce their analgesic action.


Asunto(s)
Analgésicos/farmacología , Tronco Encefálico/efectos de los fármacos , Neuronas/efectos de los fármacos , Óxido Nitroso/farmacología , Receptores Adrenérgicos alfa 2/metabolismo , Animales , Tronco Encefálico/citología , Tronco Encefálico/metabolismo , Inmunotoxinas/administración & dosificación , Inyecciones Intraventriculares , Locus Coeruleus/citología , Locus Coeruleus/efectos de los fármacos , Locus Coeruleus/metabolismo , Masculino , Ratones , Ratones Noqueados , Neuronas/citología , Neuronas/metabolismo , Dimensión del Dolor/efectos de los fármacos , Puente/citología , Puente/efectos de los fármacos , Puente/metabolismo , Proteínas Proto-Oncogénicas c-fos/metabolismo , ARN Mensajero/metabolismo , Ratas , Ratas Sprague-Dawley , Receptores Adrenérgicos/metabolismo , Receptores Adrenérgicos alfa 2/genética , Tirosina 3-Monooxigenasa/metabolismo
9.
Biochim Biophys Acta ; 1119(2): 211-7, 1992 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-1540655

RESUMEN

Poly(L-lysine) exists in a random-coil formation at a low pH, alpha-helix at a pH above 10.6, and transforms into beta-sheet when the alpha-helix polylysine is heated. Each conformation is clearly distinguishable in the amide-I band of the infrared spectrum. The thermotropic alpha-to-beta transition was studied by using differential scanning calorimetry. At pH 10.6, the transition temperature was 43.5 degrees C and the transition enthalpy was 170 cal/mol residue. At pH 11.85, the measurements were 36.7 degrees C and 910 cal/mol residue, respectively. Volatile anesthetics (chloroform, halothane, isoflurane and enflurane) partially transformed alpha-helix polylysine into beta-sheet. The transformation was reversed by the application of hydrostatic pressure in the range of 100-350 atm. Apparently, the alpha-to-beta transition was induced by anesthetics through partial dehydration of the peptide side-chains (beta-sheet surface is less hydrated than alpha-helix). High pressure reversed this process by re-hydrating the peptide. Because the membrane spanning domains of channel and receptor proteins are predominantly in the alpha-helix conformation, anesthetics may suppress the activity of excitable cells by transforming them into a less than optimal structure for electrogenic ion transport and neurotransmission. Proteins and lipid membranes maintain their structural integrity by interaction with water. That which attenuates the interaction will destabilize the structure. These data suggest that anesthetics alter macromolecular conformations essentially by a solvent effect, thereby destroying the solvation water shell surrounding macromolecules.


Asunto(s)
Polilisina/química , Conformación Proteica , Anestésicos/farmacología , Calor , Concentración de Iones de Hidrógeno , Presión Hidrostática , Conformación Proteica/efectos de los fármacos , Solventes , Espectrofotometría Infrarroja
10.
Circulation ; 103(8): 1115-20, 2001 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-11222475

RESUMEN

BACKGROUND: Although endothelial nitric oxide synthase (NOS) is antiatherogenic, the role of inducible NOS (iNOS) in the development of atherosclerosis is not established. METHODS AND RESULTS: We compared the susceptibility of iNOS knockout (iNOS(-/-)) and wild-type (iNOS(+/+)) mice to the development of atherosclerosis induced by feeding an atherogenic diet for 15 weeks. Plasma lipid level, atherosclerotic lesion size, and cellular density in the lesions were all similar in the 2 strains (lesion size: iNOS(+/+) 285+/-73x10(3) microm(2), iNOS(-/-) 293+/-82x10(3) microm(2), n=10). iNOS mRNA was detected in the lesions of iNOS(+/+) but not iNOS(-/-) mice through RT-PCR. Immunohistochemically, iNOS(+/+) mice showed iNOS staining in macrophages and medial smooth muscle cells in the lesions. Nitrotyrosine staining showed a similar distribution, whereas it was absent in iNOS(-/-) mice. There was no apparent difference in the intensity or distribution of vascular cell adhesion molecule-1 staining in the lesions of the 2 strains. However, the lesions of iNOS(+/+) mice showed a markedly decreased extracellular collagen content compared with those of iNOS(-/-) mice CONCLUSIONS: iNOS induction does not affect the development of atherosclerosis in mice fed an atherogenic diet, but the resulting lesions show decreased levels of extracellular collagen and may be more fragile.


Asunto(s)
Arteriosclerosis/enzimología , Colágeno/metabolismo , Óxido Nítrico Sintasa/metabolismo , Animales , Aorta/enzimología , Arteriosclerosis/genética , Arteriosclerosis/metabolismo , Arteriosclerosis/patología , Dieta Aterogénica , Modelos Animales de Enfermedad , Susceptibilidad a Enfermedades/enzimología , Inducción Enzimática , Femenino , Predisposición Genética a la Enfermedad , Inmunohistoquímica , Lípidos/sangre , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Óxido Nítrico Sintasa/deficiencia , Óxido Nítrico Sintasa/genética , Óxido Nítrico Sintasa de Tipo II
11.
J Bone Joint Surg Br ; 87(1): 117-9, 2005 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-15686251

RESUMEN

We have compared the energy expenditure during walking in three patients, aged between 51 and 55 years, with unilateral disarticulation of the hip when using the mechanical-controlled stance-phase control knee (Otto Bock 3R15) and the microprocessor-controlled pneumatic swing-phase control knee (Intelligent Prosthesis, IP). All had an endoskeletal hip disarticulation prosthesis with an Otto Bock 7E7 hip and a single-axis foot. The energy expenditure was measured when walking at speeds of 30, 50, and 70 m/min. Two patients showed a decreased uptake of oxygen (energy expenditure per unit time, ml/kg/min) of between 10.3% and 39.6% when using the IP compared with the Otto Bock 3R15 at the same speeds. One did not show any significant difference in the uptake of oxygen at 30 m/min, but at 50 and 70 m/min, a decrease in uptake of between 10.5% and 11.6% was found when using the IP. The use of the IP decreased the energy expenditure of walking in these patients.


Asunto(s)
Miembros Artificiales , Desarticulación , Metabolismo Energético/fisiología , Caminata/fisiología , Femenino , Articulación de la Cadera/cirugía , Humanos , Masculino , Microcomputadores , Persona de Mediana Edad , Consumo de Oxígeno/fisiología , Diseño de Prótesis
12.
J Invest Dermatol ; 86(6): 673-7, 1986 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-3711680

RESUMEN

Reduction of a commercially available, pepsin-solubilized, bovine dermal collagen (Vitrogen 100) with sodium [3H]borohydride provided radiolabeled collagen preparations with specific activities ranging from 7.1-12.0 muCi/mg collagen. These specific activities were 2-3 times greater than those obtained by reduction of intact rat tail tendon collagen under similar conditions. The alpha, beta, and higher aggregate components of type I collagen were radiolabeled as well as the alpha component of a small amount of type III collagen present in the samples. Fractionation of cyanogen bromide peptides showed that alpha 1(I)CB7, alpha 1(I)CB8, and alpha 2(I)CB3,5 were the predominant peptides labeled by this procedure. Amino acid analysis indicated that the majority of the radioactivity was in reducible cross-links, precursors of these cross-links, and in hexosyllysine residues. Reconstitution experiments comparing this radiolabeled collagen with nonlabeled collagen showed them to be indistinguishable. Bacterial collagenase digestion of this reconstituted fibrillar collagen in both a lightly cross-linked (glutaraldehyde 0.0075%) and noncross-linked form provided evidence that digestion of labeled and nonlabeled collagens proceeded at similar rates. Thus, labeling did not change the properties of the collagen. Cross-linking made the preparation refractory to proteolytic degradation. Injection of fibrillar collagen preparations, spiked with radiolabeled collagen, into the guinea pig dermis followed by quantitation of the amount of radioactivity recovered from implant sites as a function of time, indicated that the lightly cross-linked samples also were more resistant to degradation in vivo than the noncross-linked preparation. The half-life of noncross-linked collagen was about 4 days while that of the cross-linked collagen was about 25 days. These degradation rates were much faster than observed for similar, nonlabeled samples injected into the dermis of humans, presumably due to a higher metabolic activity in the guinea pig dermis.


Asunto(s)
Colágeno/uso terapéutico , Animales , Autorradiografía/métodos , Materiales Biocompatibles , Borohidruros/metabolismo , Electroforesis en Gel de Poliacrilamida , Femenino , Fluorescencia , Cobayas , Dodecil Sulfato de Sodio , Trasplante Heterólogo , Tritio
13.
FEBS Lett ; 247(2): 353-7, 1989 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-2785459

RESUMEN

Expression of protein kinase C (PKC) subspecies was studied in various human leukemia-lymphoma cell lines. The PKC in most cell lines examined was resolved into two major fractions corresponding to type II (beta-sequence) and type III (alpha-sequence) PKC of the rat brain. The amounts of these two subspecies greatly varied among the cell lines. Type I PKC (gamma-sequence) was expressed in none of the cell lines tested, but PKCs with undefined structures were frequently detected. The differential co-expression of several PKC subspecies is presumably related to the state of cell differentiation.


Asunto(s)
Leucemia/enzimología , Linfoma/enzimología , Proteína Quinasa C/metabolismo , Animales , Linfocitos B , Encéfalo/enzimología , Cromatografía , Humanos , Immunoblotting , Inmunohistoquímica , Leucemia Eritroblástica Aguda/enzimología , Leucemia Mielomonocítica Aguda/enzimología , Ratas , Linfocitos T , Células Tumorales Cultivadas
14.
Immunobiology ; 201(1): 120-32, 1999 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10532285

RESUMEN

The role of the intestinal bacterial flora on the Vbeta repertoire was examined using the gnotobiotic murine model. The ratio of Vbeta6-positive T cells in the periphery of DBA/2 mice under SPF conditions was only 2.2% (mean, n = 4), since the cells were eliminated by the endogenous superantigen Mls(a). However, the ratio in germ-free (GF) mice was 31.7%. Similarly, the contamination of the GF Mice with the intestinal flora from SPF mice reduced the ratio of Vbeta6 in GF mice from 22.9% to 13.7%. In contrast, in BALB/c mice (Mls(b)) in which Vbeta6 cells do not react with this endogenous superantigen, the ratio of Vbeta6 cells do not react with this endogenous superantigen, the ratio of Vbeta6 of SPF mice (15.4%, mean, n = 3) was found to be comparable to that of GF mice (15.6%, n = 3). These data suggested that the absence of intestinal flora deteriorated a part of the Mls(a) determinant, which reacted with the Vbeta6 T cells and thereby eliminated them, thus resulting in an increase of these cells in GF mice. Moreover, the alloantigenicity of minor histocompatible alloantigen(s) (mHAg) in SPF mice, which was detected in H-2 identical MLR experiments and a murine graft-versus-host (GVH) model, was reduced in GF and decontaminated SPF mice, thus indicating that the intestinal flora upregulated the mHAg including a part of Mls determinant. These results therefore suggest that the intestinal flora plays a role in the upregulation of mHAg including a part of endogenous superantigen and the consequent tuning of the Vbeta repertoire.


Asunto(s)
Bacterias/inmunología , Intestinos/inmunología , Intestinos/microbiología , Linfocitos T/inmunología , Animales , Enfermedad Injerto contra Huésped/inmunología , Antígenos H-2/inmunología , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos DBA , Receptores de Antígenos de Linfocitos T alfa-beta/inmunología
15.
Immunobiology ; 204(4): 442-57, 2001 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11776399

RESUMEN

Although intestinal bacterial flora has been thought to play a role in the induction of oral tolerance, the mechanism has yet to be elucidated. We therefore examined the bacterial flora-dependent acquisition of susceptibility to oral tolerance induction using a gnotobiotic murine model. Germ-free (GF) mice exhibited a significant shortage of T cells in the PPs in comparison to SPF mice. A recovery in the number of such T cells was accomplished in the gnotobiotic mice associated with Bifidobacterium infantis or Escherichia coli but not in the gnotobiotic mice with Clostridium perfringens or Staphylococcus aureus. To examine the susceptibility to oral tolerance induction, these mice were orally given ovalbumin (OVA) as a tolerogen and then injected i.p. with the Ag. The Ag-specific IgG1 in the serum remained at a low level in both SPF and those gnotobiotic mice groups containing a sufficient number of T cells in the PPs. However, no such unresponsiveness in the Ab response was observed in GF or the other gnotobiotic mice groups containing only a few T cells in the tissues. Adoptive cell transfer analysis clearly showed that a sufficient number of T cells in the PPs is required for the induction of oral tolerance. Furthermore, the reduced expression of SLC (secondary lymphoid-tissue chemokine), which is responsible for T-cell migration to lymphoid organs, was observed in the PPs of GF mice, resulting in a shortage of T cells in the tissues. However, the reduced expression of SLC was restored even in the GF mice after conventionalization, thus suggesting that the failure of oral tolerance induction is functionally coupled to the innate absence of T cells under the GF condition.


Asunto(s)
Tolerancia Inmunológica/inmunología , Ganglios Linfáticos Agregados/inmunología , Linfocitos T/inmunología , Administración Oral , Animales , Bifidobacterium/inmunología , Quimiocina CCL21 , Quimiocinas CC/inmunología , Clostridium perfringens/inmunología , Escherichia coli/inmunología , Expresión Génica , Recuento de Linfocitos , Masculino , Ratones , Ratones Endogámicos BALB C , Ovalbúmina/inmunología , Ganglios Linfáticos Agregados/citología , Organismos Libres de Patógenos Específicos , Staphylococcus aureus/inmunología , Linfocitos T/citología
16.
Microsc Res Tech ; 37(5-6): 572-82, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-9220432

RESUMEN

We have investigated the development of the Harderian glands of Japanese white rabbits from birth to 4 months of age. Although two types of secretory cells comprise the glandular epithelium of the pink and white lobes in fully developed glands, the time of neonatal appearance is different between the two. Cells consisting of the pink lobe first appear on the third day of life, while cells of the white appear around seventh day of life. The ultrastructure of the Harderian glands from 1-week-old rabbits resembles that of adult animals. The gland can be divided into three parts on the basis of their epithelial cell composition at the electron microscopic level. The respective parts are composed of: (1) one type of cells with large vacuoles (pink lobe), (2) one type of cells with small vacuoles (white lobe), and (3) two types of cells with large and small vacuoles (pink-white mixed portion). The relative number of plasma cells per 1 mm2 is low in both pink and white lobes during early postnatal life. However, in adult animals, the white lobe has a larger number of plasma cells than the pink lobe. These results suggest the possibility that the white lobe participates in the immune system more than does the pink.


Asunto(s)
Glándula de Harder/crecimiento & desarrollo , Conejos/anatomía & histología , Animales , Recuento de Células , Células Epiteliales , Epitelio/crecimiento & desarrollo , Epitelio/ultraestructura , Femenino , Glándula de Harder/citología , Glándula de Harder/ultraestructura , Masculino , Células Plasmáticas/inmunología , Células Plasmáticas/ultraestructura , Vacuolas/ultraestructura
17.
J Med Microbiol ; 40(3): 179-87, 1994 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-8114067

RESUMEN

Growth of Clostridium difficile was inhibited more strongly in continuous flow (CF) culture with C. difficile-negative faeces of infants than with C. difficile-positive faeces. Culture of faecal flora of infants yielded a greater variety of bacterial species in C. difficile-negative than in C. difficile-positive faeces. In the mixed CF culture of C. difficile with Enterococcus avium, Bacteroides distasonis, Eubacterium lentum, C. ramosum, C. perfringens and either Escherichia coli or Klebsiella pneumoniae isolated from C. difficile-negative faeces, inhibition of growth of C. difficile was demonstrated when the pH of the culture medium was decreased. Amino-acid analysis of CF cultures showed considerable utilisation of aspartic acid, serine, threonine, arginine and asparagine. A marked increase in concentrations of citrulline and ornithine was found in the culture that inhibited growth of C. difficile. The addition of citrulline and ornithine into a Gifu anaerobic medium (GAM) broth produced no inhibition of growth of C. difficile. The addition of the mixture of the depleted amino acids (aspartic acid, serine, threonine, arginine and asparagine) to the culture filtrate or adjustment of the pH of the culture filtrate induced considerable growth of C. difficile. These results suggest that the inhibition of growth of C. difficile may be due to consumption of amino acids by intestinal flora, and not to the presence of inhibitors produced by the intestinal flora.


Asunto(s)
Bacterias/crecimiento & desarrollo , Clostridioides difficile/crecimiento & desarrollo , Heces/microbiología , Aminoácidos/análisis , Aminoácidos/metabolismo , Anaerobiosis , Candida albicans/crecimiento & desarrollo , Preescolar , Clostridioides difficile/aislamiento & purificación , Ácidos Grasos Volátiles/análisis , Humanos , Concentración de Iones de Hidrógeno , Lactante
18.
Eur J Pharmacol ; 427(1): 27-35, 2001 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-11553360

RESUMEN

In previous studies using Fos expression as a marker of neuronal activation, we showed that nitrous oxide (N(2)O) activates bulbospinal noradrenergic neurons in rats and that destruction of these neuronal pathways leads to loss of N(2)O antinociceptive action. Based on previous rat studies it has been proposed that these noradrenergic neurons are activated through opioid receptors through the release of endogenous opioid ligands in the periaqueductal gray. Using mice with a disrupted preproenkephalin gene (Penk2 -/-) and the opioid receptor antagonist naltrexone, we investigated the role of enkephalinergic mechanisms and opioid receptor activation in the behavioral and bulbospinal neuron responses to N(2)O in mice. The antinociceptive response to N(2)O was investigated using the tail-flick, hot-plate, and von Frey assays, the sedative/hypnotic response was measured using rotarod and loss of righting reflex, and bulbospinal neuronal activation was assessed with pontine Fos immunostaining. No differences were observed between wild-type and Penk2 -/- mice for the antinociceptive, sedative/hypnotic, and pontine neuronal activation effects of N(2)O. Similarly, naltrexone did not block N(2)O-induced antinociception, sedation, or hypnosis. We conclude that neither enkephalin nor opioid receptors participate in either the antinociceptive or the sedative/hypnotic actions of N(2)O in mice.


Asunto(s)
Analgésicos/farmacología , Encefalinas/efectos de los fármacos , Hipnóticos y Sedantes/farmacología , Óxido Nitroso/farmacología , Receptores Opioides/fisiología , Animales , Relación Dosis-Respuesta a Droga , Encefalinas/deficiencia , Encefalinas/genética , Encefalinas/metabolismo , Genotipo , Inmunohistoquímica , Masculino , Bulbo Raquídeo/citología , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Naltrexona/farmacología , Neuronas/química , Neuronas/efectos de los fármacos , Neuronas/metabolismo , Dolor/prevención & control , Dimensión del Dolor , Precursores de Proteínas/genética , Proteínas Proto-Oncogénicas c-fos/análisis
19.
Eur J Pharmacol ; 379(2-3): 141-9, 1999 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-10497900

RESUMEN

Fos protein expression has been used to reflect neuronal activation in pain processing pathways although analgesics may uncouple behavioral and Fos responses. We determine whether formalin-induced spinal c-fos mRNA expression (Northern blotting) correlates with nocifensive behavior following pretreatment with morphine, the alpha2-adrenoceptor agonist dexmedetomidine, or their respective antagonists naloxone and atipamezole. Both opiate and alpha2-adrenoceptor agonists reduced formalin-induced c-fos gene transcription and nocifensive behavior via their cognate receptors. Unexpectedly, blockade of either the opiate or alpha2-adrenergic receptors, alone, caused an increase in formalin-evoked c-fos mRNA; while blocking the opiate receptor had no effect on formalin-induced behavior, alpha2-adrenoceptor block had an analgesic effect, indicating discordance between c-fos message transcription and nocifensive behavior. We concluded that the formalin-induced spinal c-fos signal was a poor predictor of the behavioral response to pharmacological manipulation of pain processing pathways.


Asunto(s)
Analgésicos/farmacología , Dimensión del Dolor/efectos de los fármacos , Proteínas Proto-Oncogénicas c-fos/efectos de los fármacos , ARN Mensajero/efectos de los fármacos , Médula Espinal/efectos de los fármacos , Antagonistas de Receptores Adrenérgicos alfa 2 , Animales , Formaldehído/farmacología , Inflamación/inducido químicamente , Mediadores de Inflamación/farmacología , Masculino , Antagonistas de Narcóticos , Dolor/fisiopatología , Proteínas Proto-Oncogénicas c-fos/metabolismo , ARN Mensajero/metabolismo , Ratas , Ratas Sprague-Dawley , Receptores Adrenérgicos alfa 2/fisiología , Receptores Opioides/fisiología , Médula Espinal/metabolismo
20.
FEMS Immunol Med Microbiol ; 7(1): 73-80, 1993 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-8364525

RESUMEN

A 14-year-old female patient, admitted for a closer examination of liver tumour (hepatocellular adenoma), was diagnosed as having a congenital absence of the portal vein. The blood ammonia level (approximately 120 micrograms dl-1) in the superior mesenteric vein was markedly low compared to the normal value of 300-350 micrograms dl-1 in the portal vein. The decreased ammonia concentration and urease activity of the patient's faeces were demonstrated. The dominant intestinal flora in the faeces of the patient, before operation, was Bifidobacterium sp., Bifidobacterium breve, Bifidobacterium lonqum, Lactobacillus plantarum, and after the operation Bacteroides vulgatus, Veillonella parvula, Peptococcus magnus Bifidobacterium longum. In contrast, Bifidobacterium bifidum, Bacteroides ureolyticus, Bacteroides ovatus and Bacteroides distasonis, B. ovatus, Bifidobacterium adolescentis were dominant flora in the faeces of two healthy volunteers, respectively. Among microorganisms isolated from the patient, Morganella morganii, Candida sp., Eubacterium aerofacience and Eubacterium rectale were strongly positive in urease activity in vitro; Streptococcus mitior, Staphylococcus intermedius, Micrococcus kristinae, Selenomonas ruminantum, Bacteroides ureolyticus and Lactobacillus casei ss. pseudoplantarum from the healthy volunteers. These results imply the homeostatic regulation system of faecal ammonia concentration by urease-producing microorganisms in the patient.


Asunto(s)
Bacterias/aislamiento & purificación , Intestinos/microbiología , Vena Porta/anomalías , Adolescente , Amoníaco/metabolismo , Bacterias/enzimología , Heces/química , Femenino , Humanos , Concentración de Iones de Hidrógeno , Urea/metabolismo , Ureasa/metabolismo
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