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1.
Dis Aquat Organ ; 150: 69-83, 2022 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-35833546

RESUMEN

Marine mammals, regarded as sentinels of aquatic ecosystem health, are exposed to different pathogens and parasites under natural conditions. We surveyed live South American fur seals Arctocephalus australis and South American sea lions Otaria flavescens in Uruguay for Leptospira spp., canine distemper virus (CDV), Mycobacterium spp., Toxoplasma gondii, and Neospora caninum. Samples were collected from 2007 to 2013. The seroprevalence of Leptospira spp. was 37.6% positive, 50.9% negative, and 11.5% suspect for A. australis (n = 61) while for O. flavescens (n = 12) it was 67% positive, 25% negative, and 8% suspect. CDV RNA was not detected in any of the analyzed samples. Most animals tested seropositive to tuberculosis antigens by WiZo ELISA (A. australis: 29/30; O. flavescens: 20/20); reactivity varied with a novel ELISA test (antigens MPB70, MPB83, ESAT6 and MPB59). Seroprevalence against N. caninum and T. gondii was 6.7 and 13.3% positive for O. flavescens and 0 and 2.2% positive for A. australis respectively. To evaluate possible sources of infection for pinnipeds, wild rats Rattus rattus and semi-feral cats Felis catus were also tested for Leptospira spp. and T. gondii respectively. Water samples tested for Leptospira revealed saprofitic L. bioflexa. Pathogenic Leptospira were detected in the kidneys of 2 rats, and cats tested positive for T. gondii (100%). These results represent a substantial contribution to the study of the health status of wild pinnipeds in Uruguay.


Asunto(s)
Caniformia , Enfermedades de los Gatos , Coccidiosis , Lobos Marinos , Leptospira , Enfermedades de los Roedores , Toxoplasma , Toxoplasmosis Animal , Animales , Animales Salvajes , Anticuerpos Antiprotozoarios , Gatos , Coccidiosis/parasitología , Coccidiosis/veterinaria , Ecosistema , Ratas , Estudios Seroepidemiológicos , Toxoplasmosis Animal/epidemiología , Toxoplasmosis Animal/parasitología , Uruguay/epidemiología
2.
J Helminthol ; 94: e8, 2018 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-30428941

RESUMEN

Hookworms of the genus Uncinaria parasitize pinniped pups in various locations worldwide. Four species have been described, two of which parasitize pinniped pups in the southern hemisphere: Uncinaria hamiltoni parasitizes Otaria flavescens and Arctocephalus australis from the South American coast, and Uncinaria sanguinis parasitizes Neophoca cinerea from the Australian coast. However, their geographical ranges and host specificity are unknown. Uncinaria spp. are morphologically similar, but molecular analyses have allowed the recognition of new species in the genus Uncinaria. We used nuclear genetic markers (internal transcribed spacer (ITS) and large subunit (LSU) rDNA) and a mitochondrial genetic marker (cytochrome c oxidase subunit I (COI)) to evaluate the phylogenetic relationships of Uncinaria spp. parasitizing A. australis and O. flavescens from South American coasts (Atlantic and Pacific coasts). We compared our sequences with published Uncinaria sequences. A Generalized Mixed Yule Coalescent (GMYC) analysis was also used to delimit species, and principal component analysis was used to compare morphometry among Uncinaria specimens. Parasites were sampled from A. australis from Peru (12°S), southern Chile (42°S), and the Uruguayan coast, and from O. flavescens from northern Chile (24°S) and the Uruguayan coast. Morphometric differences were observed between Uncinaria specimens from both South American coasts and between Uncinaria specimens from A. australis in Peru and southern Chile. Phylogenetic and GMYC analyses suggest that south-eastern Pacific otariid species harbour U. hamiltoni and an undescribed putative species of Uncinaria. However, more samples from A. australis and O. flavescens are necessary to understand the phylogenetic patterns of Uncinaria spp. across the South Pacific.


Asunto(s)
Ancylostomatoidea/crecimiento & desarrollo , Ancylostomatoidea/aislamiento & purificación , Caniformia/parasitología , Infecciones por Uncinaria/veterinaria , Ancylostomatoidea/clasificación , Ancylostomatoidea/genética , Animales , Chile , ADN de Helmintos/genética , ADN Espaciador Ribosómico/genética , Lobos Marinos/parasitología , Infecciones por Uncinaria/parasitología , Perú , Filogenia
3.
J Exp Med ; 194(2): 227-34, 2001 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-11457897

RESUMEN

gp49B1 is an immunoglobulin (Ig) superfamily member that inhibits FcstraightepsilonRI-induced mast cell activation when the two receptors are coligated with antibodies in vitro. The critical question of in vivo function of gp49B1 is now addressed in gene-disrupted mice. gp49B1-deficient mice exhibited a significantly increased sensitivity to IgE-dependent passive cutaneous anaphylaxis as assessed by greater tissue swelling and mast cell degranulation in situ. Importantly, by the same criteria, the absence of gp49B1 also resulted in a lower threshold for antigen challenge in active cutaneous anaphylaxis, in which the antigen-specific antibody levels were comparable in gp49B1-deficient and sufficient mice. Moreover, the absence of gp49B1 resulted in a significantly greater and faster death rate in active systemic anaphylaxis. These results indicate that gp49B1 innately dampens adaptive immediate hypersensitivity responses by suppressing mast cell activation in vivo. In addition, this study provides a new concept and target for regulation of allergic disease susceptibility and severity.


Asunto(s)
Anafilaxia/etiología , Glicoproteínas de Membrana/deficiencia , Receptores Inmunológicos , Anafilaxia/inmunología , Anafilaxia/patología , Animales , Antígenos de Superficie/genética , Antígenos de Superficie/inmunología , Edema/etiología , Edema/inmunología , Edema/patología , Femenino , Masculino , Mastocitos/inmunología , Mastocitos/patología , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/inmunología , Ratones , Ratones Endogámicos BALB C , Ratones Noqueados , Ovalbúmina/inmunología , Anafilaxis Cutánea Pasiva/genética , Anafilaxis Cutánea Pasiva/inmunología
4.
J Exp Med ; 165(3): 615-27, 1987 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-3102674

RESUMEN

The ability of mouse IL-3-dependent, bone marrow culture-derived mast cells (BMMC) to generate serosal mast cells (SMC) in vivo after adoptive transfer to mast cell-deficient mice has been defined by chemical and immunochemical criteria. BMMC differentiated and grown from WBB6F1-+/+ mouse progenitor cells in medium containing PWM/splenocyte-conditioned medium synthesized a approximately 350,000 Mr protease-resistant proteoglycan bearing approximately 55,000 Mr glycosaminoglycans, as defined by gel filtration of each. Approximately 85% of the glycosaminoglycans bound to the cell-associated BMMC proteoglycans were chondroitin sulfates based upon their susceptibility to chondroitinase ABC digestion; HPLC of the chondroitinase ABC-generated unsaturated disaccharides revealed these glycosaminoglycans to be chondroitin sulfate E. As determined by heparinase and nitrous acid degradations, approximately 10% of the glycosaminoglycans bound to BMMC proteoglycans were heparin. In contrast, mast cells recovered from the peritoneal cavity of congenitally mast cell-deficient WBB6F1-W/Wv mice 15 wk after intraperitoneal injection of BMMC synthesized approximately 650,000 Mr protease-resistant proteoglycans that contained approximately 80% heparin glycosaminoglycans of approximately 105,000 Mr. Thus, after adoptive transfer, the SMC of the previously mast cell-deficient mice were like those recovered from the normal WBB6F1-+/+ mice that were shown to synthesize approximately 600,000 Mr proteoglycans that contained approximately 80% heparin glycosaminoglycans of approximately 115,000 Mr. As assessed by indirect immunofluorescence staining and flow cytometry using the B1.1 rat mAb (an antibody that recognizes an epitope located on the neutral glycosphingolipid globopentaosylceramide), approximately 5% of BMMC bound the antibody detectably, whereas approximately 72% of the SMC that were harvested from mast cell-deficient mice 15 wk after adoptive transfer of BMMC were B1.1-positive; approximately 82% of SMC from WBB6F1-+/+ mice bound the antibody. These biochemical and immunochemical data are consistent with the results of previous adoptive transfer studies that characterized mast cells primarily on the basis of morphologic and histochemical criteria. Thus, IL-3-dependent BMMC developed in vitro, cells that resemble mucosal mast cells, can give rise in vivo to SMC that express phenotypic characteristics of connective tissue mast cells.


Asunto(s)
Células de la Médula Ósea , Mastocitos/citología , Animales , Sulfatos de Condroitina/metabolismo , Cromatografía Líquida de Alta Presión , Técnica del Anticuerpo Fluorescente , Antígeno de Forssman/análisis , Glicosaminoglicanos/metabolismo , Heparina/metabolismo , Histocitoquímica , Mastocitos/metabolismo , Mastocitos/trasplante , Ratones , Ratones Mutantes , Cavidad Peritoneal/citología , Fenotipo , Proteoglicanos/metabolismo
5.
Photodermatol Photoimmunol Photomed ; 26(6): 303-10, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21091788

RESUMEN

BACKGROUND/PURPOSE: Trans-urocanic acid is isomerized to cis-urocanic acid (C-UCA) by ultraviolet radiation. C-UCA suppresses immunity in vitro and in vivo in animals; its effect on human skin is unknown. We sought to determine whether its topical application to normal skin suppresses induction of immunity to dinitrochlorobenzene (DNCB). METHODS: Forty subjects applied C-UCA (0%, 0.02%, 0.2%, or 2%) for 17 days. A 40-mcg dose of DNCB was then applied to induce immunity. Subjects were challenged for immunity at 6-week follow-up by occluding doses of DNCB (0, 3.125, 6.25, or 12.5 mcg) on untreated normal skin. Induced immunity was measured by area of erythema and induration 2 and 4 days postchallenge. RESULTS: No significant differences were found in incidence of sensitization by C-UCA concentration (P=.59). DNCB sensitization developed in all 10 subjects induced through 0% C-UCA (placebo); only 23 of 30 patients were sensitized through skin treated with C-UCA. Mean areas of erythema and induration induced through C-UCA-treated skin were less than those in controls (P < 0.05). The number of Langerhans cells in C-UCA-treated skin was unaffected. Laboratory tests of immune function and lymphocyte numbers were unchanged. CONCLUSION: Topically applied C-UCA blunts normal induction responses to a cutaneous sensitizer.


Asunto(s)
Inmunosupresores/efectos adversos , Piel/inmunología , Rayos Ultravioleta/efectos adversos , Ácido Urocánico/efectos adversos , Adulto , Dinitroclorobenceno/administración & dosificación , Dinitroclorobenceno/inmunología , Eritema/inmunología , Femenino , Humanos , Inmunosupresores/administración & dosificación , Inmunosupresores/inmunología , Células de Langerhans/inmunología , Masculino , Persona de Mediana Edad , Estereoisomerismo , Factores de Tiempo , Ácido Urocánico/administración & dosificación , Ácido Urocánico/inmunología
6.
J Eur Acad Dermatol Venereol ; 24(2): 119-24, 2010 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-20175860

RESUMEN

Corticosteroids are a mainstay of topical therapy for psoriasis. While efficacious and relatively safe when used carefully, the potential for side effects, notably skin atrophy and adrenal suppression, have been associated with excesses in potency, prolonged or widespread use. The International Psoriasis Council Working Group on Topical Therapy has reviewed the efficacy and safety of topical corticosteroids and recommends strategies for safe, long-term use of these agents.


Asunto(s)
Corticoesteroides/uso terapéutico , Psoriasis/tratamiento farmacológico , Administración Tópica , Corticoesteroides/administración & dosificación , Corticoesteroides/efectos adversos , Humanos
7.
Science ; 185(4153): 796-8, 1974 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-4843380

RESUMEN

Rats trained on 16 two-odor discrimination problems showed rapid acquisition of a learning set and one-trial learning by the end of the problem series. Learning to sample odor cues before responding and adoption of a "win-stay, lose-shift" strategy probably accounts for the virtually errorless learning. Learning-set performance of rats trained with odor stimulus comparable to that reported for primates trained on visual cues.


Asunto(s)
Aprendizaje Discriminativo , Olfato , Animales , Odorantes , Solución de Problemas , Ratas
8.
Science ; 268(5208): 270-1, 1995 Apr 14.
Artículo en Inglés | MEDLINE | ID: mdl-17814790

RESUMEN

The thiophene oligomer alpha-hexathienylene (alpha-6T) has been successfully used as the active semiconducting material in thin-film transistors. Field-induced conductivity in thin-film transistors with alpha-6T active layers occurs only near the interfacial plane, whereas the residual conductivity caused by unintentional doping scales with the thickness of the layer. The two-dimensional nature of the field-induced conductivity is due not to any anisotropy in transport with respect to any molecular axis but to interface effects. Optimized methods of device fabrication have resulted in high field-effect mobilities and on/off current ratios of > 10(6). The current densities and switching speeds are good enough to allow consideration of these devices in practical large-area electronic circuits.

9.
Science ; 269(5230): 1560-2, 1995 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-17789448

RESUMEN

Organic field-effect transistors have been developed that function as either n-channel or p-channel devices, depending on the gate bias. The two active materials are alpha-hexathienylene (alpha-6T) and C(60). The characteristics of these devices depend mainly on the molecular orbital energy levels and transport properties of alpha-6T and C(60). The observed effects are not unique to the two materials chosen and can be quite universal provided certain conditions are met. The device can be used as a building block to form low-cost, low-power complementary integrated circuits.

10.
Science ; 254(5037): 1485-7, 1991 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-17773297

RESUMEN

Polar orientation of molecules in solids leads to materials with potentially useful properties such as nonlinear optical and electrooptical activity, electrochromism, and pyroelectricity. A simple self-assembly procedure for preparing such materials is introduced that yields multiple polar dye monolayers on solid surfaces joined by zirconium phosphate-phosphonate interlayers. Second harmonic generation (SHG) shows that the multilayers have polar order that does not decrease with increasing numbers (up to a large number) of monolayers in the film. The inorganic interlayers, as determined by SHG, impart excellent orientational stability to the dye molecules, with the onset of orientational randomization above 150 degrees C.

11.
Folia Morphol (Warsz) ; 68(4): 277-86, 2009 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-19950080

RESUMEN

The South American fur seal reproductive histophysiology is scarcely described. This study provides a histological description of prepuberal South American fur seal (Arctocephalus australis) ovaries as well as three-dimensional reconstructions of subcapsular crypts and primordial follicles. Ovaries from fresh dead animals were processed for histology and sliced into serial sections. A portion of the superficial cortex was photographed, and the images were processed using BioVis3d software in order to generate 3-dimensional reconstructions. A. australis prepuberal ovaries conform to the basic structure of pinnipedian species, with a subcapsular crypts system made up of interconnecting cisternae and tubules with multiple openings to the surface. Generally, the primordial follicles were arranged in a monolayer beneath the tunica albuginea and were closely associated with subcapsular crypts. The large number of interstitial cells distributed throughout the cortex was the main histological feature in comparison with previous reports in other seals. Three-dimensional reconstructions modelled the subcapsular crypts microarchitecture and showed the close spatial relationship between the crypts and the primordial follicles. Despite the fact that the general ovarian histological structure was similar to that of other pinnipeds, the large number of interstitial cells is a distinctive feature that raises the question about the origin and function in A. australis with regard to the steroidogenic activity reported in other seal species.


Asunto(s)
Lobos Marinos/anatomía & histología , Folículo Ovárico/anatomía & histología , Ovario/anatomía & histología , Animales , Femenino , Tamaño de los Órganos , Folículo Ovárico/citología , Ovario/citología , Células Tecales/citología
12.
J Clin Invest ; 103(12): 1737-43, 1999 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10377180

RESUMEN

SLP-76 is an adapter protein expressed in T cells and myeloid cells that is a substrate for ZAP-70 and Syk. SLP-76-deficient mice exhibit a profound block in T-cell development. We found that although SLP-76 is expressed in mouse mast cells, SLP-76(-/-) mice have normal numbers of mast cells in their skin and bronchi. SLP-76(-/-) mice are resistant to IgE-mediated passive anaphylaxis. SLP-76(-/-) mice sensitized with IgE anti-dinitrophenyl (DNP) and then challenged with DNP-HSA developed only mild and transient tachycardia, failed to increase their plasma histamine level, and all survived the antigen challenge. Bone marrow-derived mast cells (BMMCs) from SLP76(-/-) mice failed to release beta-hexosaminidase and to secrete IL-6 after FcepsilonRI cross-linking. Tyrosine phosphorylation of phospholipase C-gamma1 (but not of Syk) and calcium mobilization in response to IgE cross-linking were reduced in SLP-76-deficient BMMCs. These results suggest that SLP-76 plays an important role in FcepsilonRI-mediated signaling in mast cells.


Asunto(s)
Mastocitos/metabolismo , Fosfoproteínas/deficiencia , Fosfoproteínas/genética , Receptores de IgE/fisiología , Transducción de Señal/genética , Proteínas Adaptadoras Transductoras de Señales , Traslado Adoptivo , Animales , Sitios de Unión/genética , Células de la Médula Ósea/metabolismo , Células de la Médula Ósea/fisiología , Degranulación de la Célula/genética , Diferenciación Celular/genética , Células Cultivadas , Citocinas/metabolismo , Inmunoglobulina E/administración & dosificación , Inmunoglobulina E/fisiología , Mastocitos/fisiología , Ratones , Ratones Endogámicos , Ratones Noqueados , Anafilaxis Cutánea Pasiva , Fosfoproteínas/biosíntesis , Receptores de IgE/genética , Receptores de IgE/inmunología
13.
J Clin Invest ; 91(3): 1176-82, 1993 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-8450046

RESUMEN

Mast cell-deficient mutant mice and their normal littermates were used to determine whether activation of mast cells by anti-IgE enhances airway responsiveness to bronchoactive agonists in vivo. Pulmonary conductance was used as an index of airway response as the mice were challenged with increasing intravenous doses of methacholine (Mch) or 5-hydroxytryptamine (5-HT). Mast cell activation with anti-IgE enhanced pulmonary responsiveness to Mch in both types of normal mice (P < 0.0001 by analysis of variance) but not in either genotype of mast cell-deficient mouse. Additionally, anti-IgE pretreatment of genetically mast cell-deficient W/Wv mice whose mast cell deficiency had been repaired by infusion of freshly obtained bone marrow cells or bone marrow-derived cultured mast cells from congenic normal mice led to significant (P < 0.0001) enhancement of Mch responsiveness. 5-HT responsiveness was not significantly influenced by anti-IgE pretreatment in any of the mice studied. The data support the hypothesis that IgE-mediated activation of mast cells enhances pulmonary responsiveness to cholinergic stimulation.


Asunto(s)
Pulmón/fisiología , Mastocitos/fisiología , Cloruro de Metacolina/farmacología , Análisis de Varianza , Animales , Anticuerpos Monoclonales , Trasplante de Médula Ósea/fisiología , Relación Dosis-Respuesta a Droga , Inmunoglobulina E/inmunología , Pulmón/citología , Pulmón/efectos de los fármacos , Mastocitos/trasplante , Ratones , Ratones Endogámicos , Ratones Mutantes , Pruebas de Función Respiratoria , Serotonina/farmacología , Fenómenos Fisiológicos de la Piel
14.
J Am Acad Dermatol ; 57(2): 257-64, 2007 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-17188780

RESUMEN

BACKGROUND: Seborrheic dermatitis is commonly treated with anti-inflammatory products, including topical corticosteroids. Pimecrolimus cream 1% also exerts anti-inflammatory activity by inhibiting T-cell cytokine production. OBJECTIVE: We sought to compare the efficacy and safety of twice-daily pimecrolimus for treatment of moderate to severe facial seborrheic dermatitis. METHODS: This double-blind, vehicle-controlled, 4-week trial randomized patients with seborrheic dermatitis to pimecrolimus or vehicle (1:1). Clinical assessments (erythema [0-3] and scaling [0-3] combined for a total area score [0-6]) were performed at weeks 0, 2, and 4. Inclusion criteria included total area score 4 or greater and erythema 2 or greater. The prespecified primary variable, change from baseline in total area score at week 4, was analyzed using a two-sample t test for intent-to-treat and per protocol populations. RESULTS: In all, 96 adults of mean age 59.6 years, 88.5% male, were randomized (n = 47 pimecrolimus; 49 vehicle). At week 4, the mean change from baseline in total area score was 3.7 versus 3.3 for pimecrolimus and vehicle groups, respectively (intent-to-treat: P = .1913; 95% confidence interval (CI) for difference [-0.195, 0.961]). Per protocol analysis (n = 41 pimecrolimus; 46 vehicle) indicated a significant difference between groups (mean change 3.9 pimecrolimus vs 3.2 vehicle; P = .0156; CI [0.129, 1.197]). The superiority of pimecrolimus was observed as early as week 2 (intent-to-treat: P = .0062; CI [0.132, 0.777]; per protocol: P = .0012; CI [0.410, 1.593]). No drug-related serious adverse events occurred. The most frequent drug-related adverse events were local, mild, and transient (pimecrolimus = 26%; vehicle = 12%). LIMITATIONS: Generalizability is limited by the elderly male study population. CONCLUSION: This study suggests that pimecrolimus cream 1% is an effective and well-tolerated treatment for moderate to severe facial seborrheic dermatitis.


Asunto(s)
Antiinflamatorios no Esteroideos/uso terapéutico , Dermatitis Seborreica/tratamiento farmacológico , Dermatosis Facial/tratamiento farmacológico , Tacrolimus/análogos & derivados , Adulto , Anciano , Anciano de 80 o más Años , Antiinflamatorios no Esteroideos/administración & dosificación , Antiinflamatorios no Esteroideos/efectos adversos , Dermatitis Seborreica/patología , Método Doble Ciego , Esquema de Medicación , Erupciones por Medicamentos/etiología , Dermatosis Facial/patología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Satisfacción del Paciente , Índice de Severidad de la Enfermedad , Tacrolimus/administración & dosificación , Tacrolimus/efectos adversos , Tacrolimus/uso terapéutico , Resultado del Tratamiento
15.
J Natl Cancer Inst ; 60(5): 1023-8, 1978 May.
Artículo en Inglés | MEDLINE | ID: mdl-642024

RESUMEN

A sublethal dose of 100 mg lucanthone hydrochioride/kg (Miracil D, Nilodin; NSC-14574) administered ip into Chinese hamsters [median lethal dose for 30-day survival (LD50/30) of 315 mg/kg] reduced the radiation tolerance of the small intestine and had little or no effect on the radiation tolerance of the bone marrow. Lucanthone hydrochloride was administered at various times before and after whole-body 60Co gamma-irradiation. The median lethal dose for 7-day survival (LD50/7), indicative of death from gastrointestinal epithelial denudation, was reduced from 1,235 rads to minimum values of 995 rads or 985 rads by lucanthone hydrochloride inoculation 10 hours before irradiation or 7.5 hours post irradiation, respectively. The LD50/30, indicative of death from bone marrow stem cell depletion, remained unaltered at approximately 990 rads over the entire treatment scheme, which indicated that the radioresponsiveness of bone marrow stem cells was unaffected by lucanthone hydrochloride. The lucanthone hydrochloride effect was reversible in that control values of LD50/7 were attained by 40 hours post inoculation. Serum concentration of lucanthone hydrochloride in the Chinese hamster, determined spectrophotometrically, reached a peak of 8 microgram/ml by 1.5 hours post inoculation and then decreased exponentially with a half-life of approximately 6 hours, so that by 30 hours post inoculation it was unmeasurable.


Asunto(s)
Médula Ósea/efectos de los fármacos , Intestino Delgado/efectos de los fármacos , Lucantona/farmacología , Fármacos Sensibilizantes a Radiaciones , Animales , Antibióticos Antineoplásicos/farmacología , Médula Ósea/efectos de la radiación , Células Cultivadas , Cricetinae , Cricetulus , Relación Dosis-Respuesta a Droga , Relación Dosis-Respuesta en la Radiación , Femenino , Rayos gamma , Intestino Delgado/efectos de la radiación , Dosificación Letal Mediana , Lucantona/sangre , Lucantona/toxicidad , Masculino , Factores de Tiempo
16.
Diabetes ; 43(2): 289-96, 1994 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-8288053

RESUMEN

Both glucose and insulin are important regulators of glucose uptake and hepatic glucose release. Because insulin concentrations rarely if ever increase under daily living conditions, unless glucose concentrations also increase, we sought to determine whether hepatic and extrahepatic responses to changes in insulin and glucose concentration are impaired in patients with non-insulin-dependent diabetes mellitus (NIDDM). To address this question, glucose metabolism was measured in diabetic and nondiabetic subjects. A computer-driven infusion system was used to produce a nondiabetic postprandial insulin profile in both groups while sufficient exogenous glucose was infused to mimic nondiabetic postprandial glucose concentrations. Although NIDDM was associated with greater (P < 0.05) hepatic glucose release both before and during the prandial insulin infusion, suppression did not differ in the diabetic and nondiabetic subjects (-1.06 +/- 0.20 vs. -0.86 +/- 0.15 mmol/kg every 4 h). In contrast, stimulation of both glucose disappearance (0.77 +/- 0.27 vs. 1.68 +/- 0.27 mmol/kg every 4 h) and forearm glucose uptake (187 +/- 81 vs. 550 +/- 149 mumol/dl every 4 h) was lower (P < 0.05) in diabetic than in nondiabetic subjects. Thus, despite increased basal rates of glucose production, obese individuals with NIDDM had decreased stimulation of glucose disappearance but normal suppression of hepatic glucose release in response to nondiabetic prandial glucose and insulin concentrations. These data indicate that the increase in glucose that occurs with carbohydrate ingestion is likely to compensate for hepatic but not extrahepatic insulin resistance.


Asunto(s)
Glucemia/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Insulina/sangre , Insulina/farmacología , Hígado/metabolismo , Glucemia/efectos de los fármacos , Péptido C/sangre , Radioisótopos de Carbono , Diabetes Mellitus Tipo 2/sangre , Ingestión de Alimentos , Femenino , Antebrazo/irrigación sanguínea , Glucagón/sangre , Glucosa/metabolismo , Humanos , Lactatos/sangre , Masculino , Persona de Mediana Edad , Ácido Palmítico , Ácidos Palmíticos/sangre , Valores de Referencia , Factores de Tiempo
17.
Genetics ; 131(2): 423-47, 1992 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-1353738

RESUMEN

We report the construction of a genetic linkage map of the mouse, consisting entirely of genetic markers that can be rapidly typed by polymerase chain reaction and that show a high degree of polymorphism among inbred laboratory strains. Specifically, the map contains 317 simple sequence length polymorphisms at an average spacing of 4.3 cM and is detectably linked to approximately 99% of the mouse genome. In typical crosses between inbred laboratory strains, about 50% of the markers are polymorphic, making it straightforward to follow inheritance in almost any cross.


Asunto(s)
Marcadores Genéticos , Genoma , Ratones/genética , Polimorfismo de Longitud del Fragmento de Restricción , Animales , Secuencia de Bases , Mapeo Cromosómico , Ligamiento Genético , Ratones Endogámicos/genética , Datos de Secuencia Molecular , Reacción en Cadena de la Polimerasa , Secuencias Repetitivas de Ácidos Nucleicos
18.
Chem Sci ; 6(3): 1905-1909, 2015 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-28717452

RESUMEN

We show that a class of oligosilane-arene σ, π-hybrid materials exhibits distinct and enhanced solid-state electronic properties relative to its parent components. In the single crystal structure, the σ-conjugation axis of one molecule points towards the π-face of a neighboring molecule due to an unusual gauche conformation. This organization is hypothesized to be beneficial for charge transport. We show that solution-deposited crystalline films of the hybrid materials show up to a 100-fold increase in space-charge limited current (SCLC) mobility relative to literature reports of photoinduced hole transport in oligosilane films. The discovery that σ, π-hybrids are more than the sum of their parts offers a design opportunity for new materials.

19.
J Clin Endocrinol Metab ; 66(3): 640-4, 1988 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-3350911

RESUMEN

PDN-21, the carboxyl-terminal flanking peptide encoded by the calcitonin (CT) gene, has been found in plasma of patients with medullary thyroid carcinoma and reportedly is cosecreted with CT. To test whether PDN-21 and CT are cosecreted in normal subjects, we developed a RIA for PDN-21 and measured immunoreactive CT and PDN-21 in whole plasma and silica or C18 cartridge extracts of plasma (exCT, exPDN-21) before and after calcium (Ca) infusion (2 mg Ca/kg over 5 min) in nine normal men and nine normal women. Plasma CT and immunoreactive PDN-21 levels were often below the assay detection limits. In contrast, basal exCT and exPDN-21 were detectable in all plasma samples, and the concentrations of both were significantly higher in men than in women [basal exCT (mean +/- SE): men, 4.8 +/- 0.3 ng/L; women, 2.4 +/- 0.3 (P less than 0.001); basal exPDN-21: men, 4.7 +/- 0.3 ng/L; women, 3.3 +/- 0.3 (P less than 0.01)]. Ca infusion sharply increased CT and PDN-21 concentrations in both sexes, but the increments were greatest in men [mean (+/-SE) increment of exCT: men, 37.2 +/- 3.9 ng/L; women, 15.7 +/- 4.3 (P less than 0.002); mean increment of exPDN-21: men, 29.7 +/- 4.7 ng/L; women, 11.0 +/- 3.1 (P less than 0.005)]. The molar concentrations of exCT and exPDN-21 were closely correlated (r = 0.97; P less than 0.001). With our antiserum, the extraction-concentration technique for measurement of PDN-21 had increased sensitivity and decreased nonspecific interference compared to the whole plasma assay. We conclude that CT and PDN-21 are cosecreted from normal thyroid C-cells under the control of extracellular fluid Ca, and that men have greater secretory capacity for both peptides than women. Plasma PDN-21 may serve alternatively to CT as a marker for C-cell activity.


Asunto(s)
Calcitonina/sangre , Fragmentos de Péptidos/sangre , Adulto , Calcio/farmacología , Femenino , Humanos , Masculino , Radioinmunoensayo/métodos , Valores de Referencia
20.
Am J Psychiatry ; 146(5): 603-8, 1989 May.
Artículo en Inglés | MEDLINE | ID: mdl-2627208

RESUMEN

The Boston Psychotherapy Study found no major differences in the effects of insight-oriented and supportive psychotherapies in the treatment of schizophrenia. The authors of the current study looked beyond the assignments to those treatment designations and used blindly rated transcripts of tape-recorded sessions to examine the relationship of therapist interventions and patient outcomes at 2 years. They found significant relationships between skillfully conducted psychodynamic exploration and greater improvements in negative symptom areas of schizophrenia. The authors note the limitations and implications of these findings for clinical practice and research.


Asunto(s)
Psicoterapia , Esquizofrenia/terapia , Humanos , Evaluación de Procesos y Resultados en Atención de Salud , Psicoterapia Centrada en la Persona , Análisis de Regresión , Psicología del Esquizofrénico , Grabación en Cinta
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