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1.
J Eur Acad Dermatol Venereol ; 30(3): 442-5, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26818779

RESUMEN

BACKGROUND: Acanthosis nigricans (AN) can occur as a cutaneous manifestation of genetic diseases, one of which is associated with activating mutations of the fibroblast growth factor receptor 3 gene (FGFR3). OBJECTIVE: We explored familial AN patients with FGFR3 mutations and examined the effectiveness of glycolic acid (GA) peeling in improving their skin manifestations. METHODS: Sanger sequencing was performed for the genomic DNA extracted from leucocytes of the family members involving familial AN. GA peeling was carried out for the two patients of familial AN once every 2 weeks. RESULTS: Heterozygous c.1949A>C (p.K650T) mutation in FGFR3 was identified for the affected family members examined, whereas the wild-type sequence was found for two unaffected individuals. Hyperpigmentation and coarseness of the skin were improved by GA peeling at regular intervals with few adverse effects. CONCLUSION: We diagnosed our cases as familial generalized AN caused by heterozygous c.1949A>C (p.K650T) mutation of FGFR3. We propose that GA peeling is a useful and safe therapeutic option to treat familial AN.


Asunto(s)
Acantosis Nigricans/tratamiento farmacológico , ADN/genética , Glicolatos/administración & dosificación , Mutación , Receptor Tipo 3 de Factor de Crecimiento de Fibroblastos/genética , Piel/patología , Acantosis Nigricans/diagnóstico , Acantosis Nigricans/genética , Administración Tópica , Adolescente , Biopsia , Análisis Mutacional de ADN , Femenino , Humanos , Queratolíticos/administración & dosificación , Linaje , Receptor Tipo 3 de Factor de Crecimiento de Fibroblastos/metabolismo
7.
Phys Rev Lett ; 91(18): 183602, 2003 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-14611283

RESUMEN

We report an experimental demonstration and theoretical analysis of electromagnetically induced transparency in a GaAs quantum well, in which the absorption of an exciton resonance is reduced by more than twentyfold. The destructive quantum interference in this scheme is set up by a control pulse that couples to a resonance of biexcitons. These studies illustrate that many-particle interactions, which are inherent in semiconductors and are often detrimental to quantum coherences, can also be harnessed to manipulate these coherences.

8.
Phys Rev Lett ; 87(23): 237402, 2001 Dec 03.
Artículo en Inglés | MEDLINE | ID: mdl-11736475

RESUMEN

We report the experimental observation of coherently coupled heavy-hole-light-hole Stark shifts, i.e., light-hole exciton shifts under heavy-hole exciton pumping conditions, in InGaAs quantum wells. The theoretical analysis of the data is based on a full many-body approach (dynamics-controlled truncation formalism) in the third-order nonlinear optical regime. It is shown that the Stark shift data can be interpreted as strong evidence of suitably defined nonradiative intervalence band coherences in a semiconductor quantum well. Hence, the observations establish a semiconductor analog of Raman coherences in three-level atoms.

9.
Masui ; 50(3): 265-9, 2001 Mar.
Artículo en Japonés | MEDLINE | ID: mdl-11296437

RESUMEN

Spectral edge frequency 90 (SEF 90) and relative power in four frequency bands (beta, alpha, theta, delta) of the processed electroencephalogram were recorded in 20 patients undergoing elective gynecological surgery under total intravenous anesthesia (propofol-ketamine-fentanyl) (group PKF, n = 10) or nitrous oxide-oxygen-isoflurane (group GOI, n = 10) anesthesia. During anesthesia, mean SEF 90 and relative beta power increased more significantly in group PKF than in group GOI. At emergence from anesthesia, SEF 90 was 21.8 Hz in group PKF and 20.5 Hz in group GOI. These results suggest that it is difficult to evaluate the depth of anesthesia using pEEG under PKF anesthesia.


Asunto(s)
Periodo de Recuperación de la Anestesia , Anestesia por Inhalación , Anestesia Intravenosa , Electroencefalografía , Procedimientos Quirúrgicos Electivos , Femenino , Procedimientos Quirúrgicos Ginecológicos , Humanos , Ketamina , Monitoreo Intraoperatorio
10.
Cancer Lett ; 161(1): 97-103, 2000 Dec 08.
Artículo en Inglés | MEDLINE | ID: mdl-11078918

RESUMEN

The aim of the present study was to examine the chemopreventive efficacy of S-methylcysteine (SMC) on rat hepatocarcinogenesis induced by concurrent administration of sodium nitrite (NaNO(2)) and morpholine (Mor) using a medium-term rat liver carcinogenesis bioassay (Ito test). Administration of SMC caused significant reduction in the areas of glutathione S-transferase placental form positive foci along with a significant decrease of hepatocyte 5-bromo-2'-deoxyuridine (BrdU) labeling indices. These results demonstrated potent chemopreventive effects of SMC against hepatocarcinogenesis due to concurrent administration of Mor and NaNO(2). SMC could thus be an effective chemopreventive agent for decreasing the risk of carcinogenicity from environmental precursors of N-nitroso compounds.


Asunto(s)
Anticarcinógenos/farmacología , Cisteína/farmacología , Conservantes de Alimentos/toxicidad , Neoplasias Hepáticas Experimentales/prevención & control , Morfolinas/toxicidad , Nitrito de Sodio/toxicidad , Animales , Peso Corporal/efectos de los fármacos , Bromodesoxiuridina/metabolismo , Carcinógenos/farmacocinética , Carcinógenos/toxicidad , División Celular/efectos de los fármacos , Cisteína/análogos & derivados , Interacciones Farmacológicas , Conservantes de Alimentos/farmacocinética , Mucosa Gástrica/metabolismo , Glutatión Transferasa/metabolismo , Hígado/anatomía & histología , Hígado/efectos de los fármacos , Neoplasias Hepáticas Experimentales/inducido químicamente , Neoplasias Hepáticas Experimentales/enzimología , Masculino , Morfolinas/antagonistas & inhibidores , Morfolinas/farmacocinética , Nitrosaminas/metabolismo , Lesiones Precancerosas/inducido químicamente , Lesiones Precancerosas/enzimología , Lesiones Precancerosas/prevención & control , Ratas , Ratas Endogámicas F344 , Nitrito de Sodio/antagonistas & inhibidores , Nitrito de Sodio/farmacocinética
11.
Arch Ital Biol ; 136(3): 153-66, 1998 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-9645306

RESUMEN

Experiments were performed on 16 adult spinalized (L2) cats. Postsynaptic potentials (PSPs) produced by electrical stimulation of afferent nerves innervating foot pads were recorded from hindlimb motoneurons innervating the following hindlimb muscles: the posterior biceps and semitendinosus (PBSt), anterior biceps and semimembranosus (ABSm), lateral gastrocnemius and soleus (LGS), medial gastrocnemius (MG), plantaris (P1), tibialis anterior (TA), popliteus (Pop), flexor digitorum longus and flexor hallucis longus (FDHL) and peroneus longus (Per.l). The rate of occurrence of different types of PSPs (EPSPs, IPSPs and mixed PSPs), the size of the PSPs and their central latencies were analyzed for each group of motoneurons to identify the neural pathways from the afferents innervating foot pads to hindlimb motoneurons. The rates of occurrence of different types of PSPs did not depend on the foot pad stimulated in PBSt, ABSm and LGS motoneurons, but for other groups of motoneurons their rates of occurrence depended on the foot pad stimulated. It was often noted that the size of PSPs in the same motoneurons differed according to the foot pad stimulated. Measurements of the central latencies of the PSPs indicated that the shortest neural pathways for EPSPs and IPSPs were disynaptic (central latencies < 1.8 ms). The functional role of neuronal pathways from afferent nerves innervating foot pads to hindlimb motoneurons could be to maintain stability of the foot during different postural and motor activities.


Asunto(s)
Estado de Descerebración/fisiopatología , Miembro Posterior/inervación , Neuronas Motoras/fisiología , Neuronas Aferentes/fisiología , Animales , Gatos , Estimulación Eléctrica , Electrofisiología , Potenciales Postsinápticos Excitadores/fisiología , Femenino , Masculino , Vías Nerviosas/fisiopatología
12.
Brain Res ; 788(1-2): 327-31, 1998 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-9555080

RESUMEN

Postsynaptic potentials evoked in motoneurons innervating m. posterior biceps and semitendinosus (PBSt) and m. triceps surae (GS) by low threshold afferents from various tail muscles located at the level of the second-third caudal vertebrae were investigated in the non-anesthetized and spinalized cat. Afferent inputs from tail muscles on both sides predominantly evoked depolarizing potential in PBSt motoneurons and hyperpolarizing potential in GS motoneurons. The findings suggest that in general, tail muscle afferents facilitate flexor and inhibit extensor hindlimb motoneurons through polysynaptic pathways, so that the pelvic girdle is kept in a low position to maintain the stability of the body irrespective of different movements or posture of the tail.


Asunto(s)
Potenciales Postsinápticos Excitadores , Miembro Posterior/inervación , Neuronas Motoras/fisiología , Unión Neuromuscular/fisiología , Neuronas/fisiología , Vías Aferentes/fisiología , Animales , Gatos , Estado de Descerebración , Femenino , Masculino , Cola (estructura animal)/inervación
13.
Arch Ital Biol ; 136(1): 45-57, 1998 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-9492944

RESUMEN

Postsynaptic potentials (PSPs) were recorded in motoneurons innervating the m. posterior biceps and semitendinosus (PBSt-MN) and m. triceps surae (GS-MN) in 19 spinalized adult cats, after electrical stimulation of the dorsal and ventral tail cutaneous nerves (TDC and TVC). With stimulation at 1,5-5 time threshold, inhibitory PSPs (IPSPs), excitatory PSPs (EPSPs), and mixed PSPs (IPSP/EPSPs, EPSP/IPSPs) were recorded in approximately 90% of PBSt-MN and 70% of GS-MN. IPSPs (IPSPs, IPSP/EPSPs) after stimulation of the contralateral TVC and TDC were observed in 54% and 52% of PBSt motoneurons, respectively. EPSPs (EPSP, EPSP/IPSPs) were recorded after stimulation of ipsilateral TVC in 56% of PBSt motoneurons. IPSPs produced after stimulation of ipsilateral TDC and TVC were observed in 65% and 63%, respectively, of GS-MN showing PSPs after stimulation of tail cutaneous nerves. Measurement of segmental latencies of the earliest PSPs (PBSt-MN, IPSPs: 2.1-7.4 ms, EPSPs: 3.1-18.9 ms, GS-MN, IPSPs: 2.5-17.1 ms, EPSPs: 4.2-19.4 ms) suggested that most of the neural pathways from tail cutaneous afferents to hindlimb motoneurons are at least trisynaptic in the L7 spinal segments. Hemisection of spinal cord at S1-S2 indicated that neural pathways from both the ipsilateral and contralateral low threshold cutaneous afferents pass through the ipsilateral spinal cord at S1-S2. The neural pathways from tail cutaneous afferents to hindlimb motoneurons to maintain the balance of the pelvic girdle were discussed.


Asunto(s)
Estado de Descerebración/fisiopatología , Miembro Posterior/inervación , Neuronas Motoras/fisiología , Neuronas Aferentes/fisiología , Piel/inervación , Cola (estructura animal)/inervación , Animales , Gatos , Estimulación Eléctrica , Femenino , Masculino , Potenciales de la Membrana/fisiología , Vías Nerviosas/anatomía & histología , Vías Nerviosas/fisiología , Sinapsis/fisiología
14.
Arch Ital Biol ; 134(3): 207-15, 1996 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-8805951

RESUMEN

Responses of motoneurons supplying two tail muscles (m. extensor caudae lateralis [ECL] and m. flexor caudae longus [FCL]) to stimulation of the medial longitudinal fasciculus (MLF) and lateral vestibular nucleus (LVN) were studied using intracellular recording in the decerebrate cat. Stimulation of the MLF and the LVN produced mainly excitatory postsynaptic potentials (EPSPs) or mixed PSPs (EPSP/IPSPs), but inhibitory postsynaptic potentials (IPSPs) were also observed in a few motoneurons. The segmental latencies of early PSPs produced by MLF or LVN stimulation were distributed over a wide range, and PSPs with a segmental latency of mono- or disynaptic origin were observed in ECL and FCL motoneurons. The spatial facilitation technique indicated convergence of the descending pathways from MLF and LVN on a common interneuron.


Asunto(s)
Estado de Descerebración/fisiopatología , Neuronas Motoras/fisiología , Médula Espinal/fisiología , Cola (estructura animal)/inervación , Núcleos Vestibulares/fisiología , Animales , Gatos , Vías Eferentes/citología , Vías Eferentes/fisiología , Estimulación Eléctrica , Potenciales Evocados Somatosensoriales/fisiología , Femenino , Miembro Posterior/inervación , Miembro Posterior/fisiología , Interneuronas/fisiología , Masculino , Potenciales de la Membrana/fisiología , Músculo Esquelético/inervación , Músculo Esquelético/fisiología , Médula Espinal/citología , Núcleos Vestibulares/citología
15.
J Vet Med Sci ; 57(1): 87-92, 1995 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-7756432

RESUMEN

The postnatal development of motoneurons in two tail muscles, the extensor caudae medialis (ECM) and extensor caudae lateralis (ECL), and that of ECL muscle fibers were studied in cats 1 week to 2 months old. The location of ECL and ECM motoneurons in cats of different ages did not change postnatally. Somal size (average of maximal and minimal diameters) of ECL and ECM motoneurons gradually increased, and the size distribution of ECL was bimodal at 2 months. The activities of succinate dehydrogenase (SDH) and phosphofructokinase (PFK) were studied to determine oxidative and glycolytic activities in ECL growth. SDH activity rapidly decreased between 1 week and 2 weeks of age, while PFK activities increased gradually.


Asunto(s)
Gatos/crecimiento & desarrollo , Neuronas Motoras/fisiología , Desarrollo de Músculos , Músculo Esquelético/crecimiento & desarrollo , Cola (estructura animal)/anatomía & histología , Cola (estructura animal)/crecimiento & desarrollo , Animales , Músculo Esquelético/enzimología , Fosfofructoquinasa-1/metabolismo , Succinato Deshidrogenasa/metabolismo , Cola (estructura animal)/inervación , Factores de Tiempo
16.
J Chromatogr B Biomed Appl ; 663(1): 25-33, 1995 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-7704210

RESUMEN

Two human type V collagen sub-molecular species, designated [alpha 1(V)]2 alpha 2(V) and alpha 1(V)alpha 2(V)alpha 3(V), were purified chromatographically from a commercially available preparation, in which cystine-rich collagenous contaminants were contained, with a column packed with Fractogel EMD SO3-. From bovine crude preparations, the [alpha 1(V)]2 alpha 2(V) form free from the collagenous contaminants was purified. Type V collagen subunit chains were isolated from each type V collagen molecule by anion-exchange HPLC with a Bakerbond PEI Scout column. The highly purified human type V collagen molecules and their subunit chains were used to examine the inhibitory effect on human umbilical vein endothelial cell proliferation. It was confirmed that the alpha 1(V) chain has inhibitory activity and it was found that the inhibitory effect of the [alpha 1(V)]2 alpha 2(V) form is stronger than that of the alpha 1(V)alpha 2(V)alpha 3(V) form and that the alpha 3(V) chain has no inhibitory activity.


Asunto(s)
Adhesión Celular/efectos de los fármacos , Colágeno/aislamiento & purificación , Endotelio Vascular/citología , Animales , Bovinos , División Celular/efectos de los fármacos , Cromatografía Líquida de Alta Presión/métodos , Colágeno/química , Colágeno/farmacología , Electroforesis en Gel de Poliacrilamida , Femenino , Humanos , Sustancias Macromoleculares , Placenta/química , Tendones/química , Venas Umbilicales
17.
Nihon Jinzo Gakkai Shi ; 35(4): 365-70, 1993 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-8341014

RESUMEN

Renal tissues from 171 patients with different glomerulopathies and 6 normal controls were examined by an immunofluorescent technique. Specimens were stained in particular with anti-Amyloid P (AP) antisera, and were also stained for immunoglobulins and complement. The intensity and distribution pattern of AP staining were studied. The AP staining revealed a faint/linear pattern in normal controls, and was granular and linear in pathological specimens. The distribution of AP was found to be mesangial, capillary and mesangiocapillary. According to the degree of AP intensity, the patients were divided into two groups: group I (56 patients) exhibiting a faint intensity as seen in the normal controls, and group II (115 patients) with a strong intensity. The histological findings and laboratory data were compared between the two groups as well as among patients with different diseases. The incidence of sclerotic lesions and the amount of proteinuria were significantly higher in group II than in group I. Increased amounts of AP deposition in different glomerular diseases thus appear to be related to a diminished renal function or glomerular damage.


Asunto(s)
Glomerulonefritis/metabolismo , Componente Amiloide P Sérico/metabolismo , Adolescente , Adulto , Técnica del Anticuerpo Fluorescente , Glomerulonefritis Membranoproliferativa/metabolismo , Glomeruloesclerosis Focal y Segmentaria/metabolismo , Humanos , Persona de Mediana Edad
18.
Biomaterials ; 13(4): 235-9, 1992.
Artículo en Inglés | MEDLINE | ID: mdl-1520829

RESUMEN

The blood compatibility of a cellulose haemodialysis membrane whose surface was grafted with a methacrylate having a phospholipid polar group, 2-methacryloyloxyethyl phosphorylcholine, was evaluated with attention to platelet adhesion to the membrane surface and complement activation induced by the membrane. When the original cellulose membrane came in contact with platelet-rich plasma for 30 min, numerous platelets adhered to the surface and aggregated. On the other hand, the membrane grafted with 2-methacryloyloxyethyl phosphorylcholine effectively suppressed platelet adhesion and activation. This effect became more pronounced with increasing surface distribution. Especially, the 2-methacryloyloxyethyl phosphorylcholine grafted membranes, whose distribution exceeded 0.27, completely inhibited platelet adhesion, even when the contact time was 180 min. Moreover, the complement activation was also reduced with increased 2-methacryloyloxyethyl phosphorylcholine distribution on the surface of the membrane.


Asunto(s)
Celulosa/farmacología , Membranas Artificiales , Metacrilatos/farmacología , Fosforilcolina/análogos & derivados , Diálisis Renal/instrumentación , Animales , Materiales Biocompatibles , Proteínas Sanguíneas/efectos de los fármacos , Proteínas Sanguíneas/metabolismo , Celulosa/química , Activación de Complemento/efectos de los fármacos , Metacrilatos/química , Fosforilcolina/química , Fosforilcolina/farmacología , Adhesividad Plaquetaria/efectos de los fármacos , Conejos
19.
Am J Nephrol ; 12(1-2): 22-8, 1992.
Artículo en Inglés | MEDLINE | ID: mdl-1415361

RESUMEN

In order to clarify the difference of clinical and pathological features between the IgA nephropathy patients with acute and insidious onset, 427 patients were examined in this study. Seventy-eight patients with acute onset (group 1) were often associated with mucosal system infections at the abrupt onset. This group revealed macroscopic hematuria, more severe microscopic hematuria (more than 20/hpf), higher glomerular filtration rate (p less than 0.01) and lower serum levels of C3 (p less than 0.01). It had also a significantly higher incidence of exudative lesions (p less than 0.001). On the other hand, the onset of 349 patients (group 2) was noticed to be insidious without preceding infections. This group showed a more severe increase in mesangial cells (p less than 0.01) and a significantly higher incidence of adhesion, arterial sclerosis and tubulointerstitial changes. Deposition of Clq, C4 and IgM and detachment of visceral epithelium from the basement membrane were more frequently seen in group 2. Twenty-seven of 345 patients followed for at least 1 year after the biopsy were on maintenance hemodialysis: 1 patient was in group 1 and 26 were in group 2. These results clarified that there was a difference in clinical, laboratory and histopathological findings between the patients with IgA nephropathy with acute and insidious onset.


Asunto(s)
Glomerulonefritis por IGA/patología , Glomérulos Renales/patología , Enfermedad Aguda , Adolescente , Adulto , Anciano , Biopsia , Enfermedad Crónica , Complemento C1q/metabolismo , Complemento C4/metabolismo , Femenino , Tasa de Filtración Glomerular , Glomerulonefritis por IGA/complicaciones , Glomerulonefritis por IGA/metabolismo , Hematuria/etiología , Humanos , Inmunoglobulina A/metabolismo , Inmunoglobulina M/metabolismo , Masculino , Microscopía Electrónica , Persona de Mediana Edad
20.
Nihon Jinzo Gakkai Shi ; 33(11): 1135-40, 1991 Nov.
Artículo en Japonés | MEDLINE | ID: mdl-1808364

RESUMEN

A 26-year-old female patient complicated with reflux nephropathy and pheochromocytoma is reported. We could not find either intrinsic or extrinsic factor of urinary tract obstruction. The open bilateral renal biopsy was performed at the time of resection of the tumor. The renal biopsy specimen demonstrated minor glomerular change, severe tubular "thyroid-like" appearance and cast formation in the obvious reflux side. Otherwise focal glomerular sclerosis (FGS) lesion was found in less reflux side. In reflux nephropathy, FGS lesion is reported as main cause of progression, but mechanism of FGS lesion is unknown. This case which has both vesicoureteral reflux the high plasma nor-epinephrine concentration was considered to be important to emphasize circulative factor in the pathogenesis of FGS like lesion.


Asunto(s)
Neoplasias de las Glándulas Suprarrenales/complicaciones , Glomeruloesclerosis Focal y Segmentaria/etiología , Feocromocitoma/complicaciones , Reflujo Vesicoureteral/complicaciones , Adulto , Femenino , Glomeruloesclerosis Focal y Segmentaria/patología , Humanos , Riñón/patología , Norepinefrina/sangre , Reflujo Vesicoureteral/diagnóstico
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