Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 97
Filtrar
1.
J Genet Couns ; 30(5): 1285-1291, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34558759

RESUMEN

The COVID-19 pandemic poses a significant challenge to healthcare professionals and health systems around the world, most notably the disruption of its service delivery. The typical work setting for most genetic counselors (GCs) is in a clinic or hospital. However, during the COVID-19 pandemic, to help prevent the further spread of the virus, clinics and hospitals have restricted non-urgent in-person delivery of healthcare services, including genetic counseling. Patients' access to genetic counseling services has thus been limited, which prompted GCs in the country to utilize an alternative way to provide counseling through telegenetics. With the expansion of genetic services in the country, including the full implementation of expanded newborn screening, there is an increasing demand for genetic counseling and a growing need for telegenetics.


Asunto(s)
COVID-19 , Telemedicina , Asesoramiento Genético , Humanos , Recién Nacido , Pandemias , Filipinas , SARS-CoV-2
2.
Acta Medica Philippina ; : 394-399, 2020.
Artículo en Inglés | WPRIM (Pacífico Occidental) | ID: wpr-979898

RESUMEN

Introduction@#Midwives play an important role in promoting newborn screening (NBS) and they ensure that all Filipino newborns are offered screening for life-threatening metabolic conditions. Of the disorders included in NBS, Glucose 6 Phosphate Dehydrogenase (G6PD) deficiency is the most common disorder detected. @*Objectives@#This study aimed to assess the knowledge, self-perceived role, and experience of midwives who practice in urban and rural settings in educating parents of a newborn who are confirmed cases for G6PD deficiency. @*Method@#One-on-one semi structured interview was conducted among 21 midwives from Manila City and Lipa, Batangas, Philippines. @*Results@#The study findings indicate that midwives frequently serve as the primary information resource for parents of infants with G6PD deficiency. Assessment of knowledge showed that midwives have sufficient knowledge about the medical management and the necessary follow-up of infants with G6PD deficiency. However, it also revealed that they have inadequate knowledge of the underlying genetic cause of G6PD deficiency. The surveyed midwives recognized their role and the importance of proper education regarding G6PD deficiency. @*Conclusion@#The findings of this study identified gaps in the midwives’ knowledge on the genetic mechanisms and inheritance of G6PD deficiency, which could be a basis to improve the education and dissemination of information and to eventually improve parental education and care of newborns with G6PD deficiency


Asunto(s)
Asesoramiento Genético , Deficiencia de Glucosafosfato Deshidrogenasa , Tamizaje Neonatal
3.
Int J Mol Imaging ; 2011: 828151, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21603241

RESUMEN

Aim. To develop a method and obtain proof-of-principle for immunolymphoscintigraphy for identification of metastatic sentinel nodes. Methods. We selected one of four tumour-specific antibodies against human breast cancer and investigated (1), in immune-deficient (nude) mice with xenograft human breast cancer expressing the antigen if specific binding of the intratumorally injected, radioactively labelled, monoclonal antibody could be scintigraphically visualized, and (2) transportation to and retention in regional lymph nodes of the radioactively labelled antibody after subcutaneous injection in healthy rabbits. Results and Conclusion. Our paper suggests the theoretical possibility of a model of dual isotope immuno-lymphoscintigraphy for noninvasive, preoperative, malignant sentinel node imaging.

4.
Diabetes Obes Metab ; 11(8): 795-803, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19519868

RESUMEN

AIM/HYPOTHESIS: Combination therapies are increasingly common in the clinical management of type 2 diabetes. We investigated to what extent combined treatment with the human glucagon-like peptide-1 (GLP-1) analogue liraglutide and the dual PPARalpha/gamma agonist ragaglitazar would improve glycaemic control in overtly diabetic Zucker diabetic fatty (ZDF) rats. METHODS: Ninety overtly diabetic male ZDF rats were stratified into groups with matched haemoglobin A1c (HbA1c) (9.0+/-0.1%). Liraglutide (15 and 50 microg/kg subcutaneously twice daily), ragaglitazar (1 and 3 mg/kg perorally once daily) and their vehicles were studied as monotherapy and in combination in a 3x3 factorial design. RESULTS: After 4-week treatment, synergistic effects on HbA1c, non-fasting morning blood glucose (BG) and/or 24-h BG profiles were observed with three of the four combinations. The relationship between plasma insulin and BG in combination-treated animals approached that of historical lean ZDF rats representing normal glucose homeostasis, suggesting that insulin secretion and insulin sensitivity were markedly improved. Increased insulin immunostaining in islets further supports the improved beta-cell function and/or insulin sensitivity in combination-treated animals. The synergistic effect on glycaemic control was found without a similar synergistic increase in beta-cell mass in the combination groups. CONCLUSIONS/INTERPRETATION: Our data demonstrate that combination treatment with a human GLP-1 analogue and a dual PPARalpha/gamma agonist through distinct mechanism of actions synergistically improves glycaemic control in the ZDF rat.


Asunto(s)
Glucemia/efectos de los fármacos , Diabetes Mellitus/tratamiento farmacológico , Péptido 1 Similar al Glucagón/análogos & derivados , Hipoglucemiantes/farmacología , Oxazinas/uso terapéutico , Fenilpropionatos/uso terapéutico , Animales , Proliferación Celular/efectos de los fármacos , Modelos Animales de Enfermedad , Sinergismo Farmacológico , Péptido 1 Similar al Glucagón/uso terapéutico , Hemoglobina Glucada/análisis , Proteínas de Homeodominio/análisis , Homeostasis/efectos de los fármacos , Inmunohistoquímica , Insulina/sangre , Células Secretoras de Insulina/efectos de los fármacos , Células Secretoras de Insulina/inmunología , Liraglutida , Ratas , Ratas Zucker , Transactivadores/análisis
5.
Br J Dermatol ; 160(2): 284-96, 2009 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18945296

RESUMEN

BACKGROUND: Interleukin (IL)-20 is a recently discovered cytokine displaying increased levels in psoriatic lesions. Interestingly, IL-20 levels decrease with antipsoriatic treatment, correlating with clinical improvement. However, the role of IL-20 in the aetiology of psoriasis is unknown. OBJECTIVES: In this study, we investigate the effects both of blocking IL-20 signalling in psoriatic plaques and of adding IL-20 to nonlesional psoriasis skin. METHODS: We employed the human skin xenograft transplantation model in which psoriatic plaques and nonlesional keratome skin biopsies obtained from donors with moderate to severe plaque psoriasis were transplanted on to immuno-deficient mice. The transplanted mice were treated with anti-IL-20 antibodies or recombinant human IL-20. RESULTS: We demonstrate that blocking IL-20 signalling with anti-IL-20 antibodies induces psoriasis resolution and inhibits psoriasis induction. We also demonstrate that continuous IL-20 infusion, together with injection of additional nonactivated leucocytes, promotes induction of psoriasis in nonlesional skin from patients with psoriasis. CONCLUSIONS: The results suggest that IL-20 plays a critical role in the induction and maintenance of psoriasis, and IL-20 is suggested as a new possible specific target in psoriasis treatment.


Asunto(s)
Interleucinas/fisiología , Psoriasis/etiología , Transducción de Señal/inmunología , Trasplante de Piel , Adulto , Anciano , Animales , Especificidad de Anticuerpos/inmunología , Proliferación Celular , Humanos , Interleucinas/antagonistas & inhibidores , Interleucinas/inmunología , Ratones , Ratones SCID , Persona de Mediana Edad , Psoriasis/tratamiento farmacológico , Psoriasis/inmunología , Proteínas Recombinantes/inmunología , Inducción de Remisión , Trasplante Heterólogo
6.
Microvasc Res ; 75(2): 169-78, 2008 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-17976661

RESUMEN

The matrix-inserted surface transplantation model is an in vivo assay used to analyse the kinetics of tumor-vessel interactions during different stages of skin carcinoma progression. This system allows the study of host-tumor interface, i.e. penetration of tumor cells into normal host tissue as well as infiltration of normal host cells into the tumor. In the present study, image analysis algorithms for processing and quantifying the extent of such migratory and tissue remodeling events are presented. The proposed method is non-parametric and its originality lies in its particularity to take into account the specific geometry of tumor-host interface. This methodology is validated by evaluating the contribution of matrix metalloproteases (MMPs) in skin carcinoma invasion and vascularization through pharmacological and genetic approaches.


Asunto(s)
Neovascularización Patológica/patología , Procesamiento de Señales Asistido por Computador , Neoplasias Cutáneas/irrigación sanguínea , Neoplasias Cutáneas/patología , Algoritmos , Inhibidores de la Angiogénesis/farmacología , Inhibidores de la Angiogénesis/uso terapéutico , Animales , Línea Celular Tumoral , Movimiento Celular , Dipéptidos/farmacología , Dipéptidos/uso terapéutico , Cinética , Metaloproteinasas de la Matriz Secretadas/antagonistas & inhibidores , Metaloproteinasas de la Matriz Secretadas/genética , Metaloproteinasas de la Matriz Secretadas/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Modelos Estadísticos , Invasividad Neoplásica , Neovascularización Patológica/enzimología , Neovascularización Patológica/prevención & control , Inhibidores de Proteasas/farmacología , Inhibidores de Proteasas/uso terapéutico , Reproducibilidad de los Resultados , Neoplasias Cutáneas/enzimología , Neoplasias Cutáneas/prevención & control , Células del Estroma/patología
7.
J Thromb Haemost ; 5(9): 1936-44, 2007 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-17723133

RESUMEN

BACKGROUND: Degradation of extracellular matrix proteins, such as fibrin, is pivotal to tumor invasion. Inhibition of the interaction between urokinase plasminogen activator (u-PA) and its receptor (u-PAR), and hence pro-u-PA activation, is an attractive approach to anti-invasive cancer therapy. A number of inhibitors exist for the human system, but because of species specificity none of these are efficient in mice. We have recently generated an inhibitory monoclonal antibody (mAb) against mouse u-PAR (mR1) by immunization of u-PAR-deficient mice. OBJECTIVES: To evaluate the effect of mR1 in vivo in a physiological setting sensitive to deregulated fibrinolysis, we have administered mR1 systemically and quantitated the effect on liver fibrin accumulation. METHODS: Wild-type and tissue-type plasminogen activator (t-PA) deficient mice were administered with mR1, or control antibody, during 6 weeks. Thereafter, the livers were retrieved and the amount of liver fibrin measured by unbiased morphometrical analysis of immunofluorescence signal. RESULTS: Systemic administration of mR1 caused significantly increased fibrin signal in anti-u-PAR treated t-PA-deficient mice compared to mock-treated, which mimics the phenotype of u-PAR;t-PA double-deficient mice. Fibrin and fibronectin accumulated within the sinusoidal space and was infiltrated by inflammatory cells. Analysis of small and rare hepatic fibrin plaques observed in t-PA-deficient mice showed infiltrating macrophages that, contrary to surrounding Kuppfer cells, expressed u-PAR. CONCLUSION: We show that u-PAR-expressing macrophages are involved in cell-mediated fibrinolysis of liver fibrin deposits, and that the antimouse-u-PAR mAb is effective in vivo and thus suited for studies of the effect of targeting the u-PA/u-PAR interaction in mouse cancer models.


Asunto(s)
Anticuerpos Monoclonales/administración & dosificación , Fibrina/metabolismo , Hígado/efectos de los fármacos , Receptores de Superficie Celular/inmunología , Activador de Tejido Plasminógeno/genética , Animales , Anticuerpos Monoclonales/farmacología , Técnica del Anticuerpo Fluorescente , Hígado/metabolismo , Ratones , Ratones Endogámicos C57BL , Receptores del Activador de Plasminógeno Tipo Uroquinasa
8.
J Mol Endocrinol ; 35(2): 231-43, 2005 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16216905

RESUMEN

Growth hormone and prolactin are important growth factors for pancreatic beta-cells. The effects exerted by these hormones on proliferation and on insulin synthesis and secretion in beta-cells are largely mediated through the Janus kinase (JAK)/signal transducer and activator of transcription (STAT) signaling pathway. Suppressors of cytokine signaling (SOCS) proteins are specific inhibitors of the JAK/STAT pathway acting through a negative-feedback loop. To investigate in vivo effects of SOCS-3 in growth hormone (GH)/prolactin signaling in beta-cells we generated transgenic mice with beta-cell-specific overexpression of SOCS-3. The relative beta-cell proliferation and volume in the mice were measured by morphometry. Beta-cell volume of transgenic female mice was reduced by over 30% compared with beta-cell volume in wild-type female mice. Stimulation of transgenic islets in vitro with GH showed a reduced tyrosine phosphorylation of STAT-5 when compared with wild-type islets. Transduction of primary islet cultures with adenoviruses expressing various SOCS proteins followed by stimulation with GH or glucagon-like peptide-1 (GLP-1) revealed that SOCS-3 inhibited GH- but not GLP-1-mediated islet cell proliferation, indicating that the decreased beta-cell volume observed in female transgenic mice could be caused by an inhibition of GH-induced beta-cell proliferation by SOCS-3. In spite of the reduced beta-cell volume the transgenic female mice exhibited enhanced glucose tolerance compared with wild-type littermates following an oral glucose-tolerance test. Together these data suggest that SOCS-3 modulates cytokine signaling in pancreatic beta-cells and therefore potentially could be a candidate target for development of new treatment strategies for diabetes.


Asunto(s)
Proliferación Celular , Células Secretoras de Insulina/citología , Células Secretoras de Insulina/fisiología , Proteínas Supresoras de la Señalización de Citocinas/metabolismo , Animales , Glucemia/metabolismo , Peso Corporal , Femenino , Péptido 1 Similar al Glucagón/metabolismo , Prueba de Tolerancia a la Glucosa , Hormona del Crecimiento/metabolismo , Hibridación in Situ , Insulina/metabolismo , Janus Quinasa 1 , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos DBA , Ratones Transgénicos , Proteínas Tirosina Quinasas/metabolismo , Distribución Aleatoria , Ratas , Factor de Transcripción STAT5/metabolismo , Transducción de Señal/fisiología , Proteína 3 Supresora de la Señalización de Citocinas , Proteínas Supresoras de la Señalización de Citocinas/genética , Transgenes
9.
Clin Exp Immunol ; 141(3): 549-57, 2005 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16045746

RESUMEN

Summary CD4(+)CD25(+) regulatory T cells (T(regs)) are involved in the maintenance of peripheral tolerance and ensure a balanced immune response competent of fighting pathogens and at the same time recognizing commensals as harmless. This feature is lost in Crohn's disease (CD). The forkhead/winged helix transcription factor FoxP3 is a master gene for T(reg) function and defects in the FoxP3 gene lead to a clinical picture similar to inflammatory bowel disease (IBD). Murine colitis can be cured by adoptive transfer of T(regs) and ex vivo-generated gut-specific T(regs) represent an attractive option for therapy in CD. Thus, defective T(regs) could contribute to the development of CD. We cultured biopsies of colonic mucosa in the presence of high concentrations of interleukin (IL)-2 and IL-4 to overcome the anergic nature of naturally occurring CD4(+)CD25(+) T(regs) in the mucosa. We investigated the expression of FoxP3 and regulatory potential of gut-derived CD4(+)CD25(+) T cells cultured from patients with CD and healthy individuals. The FoxP3 expression was analysed by reverse transcriptase polymerase chain reaction (RT-PCR), and the suppressive effect of FoxP3(+)CD4(+)CD25(+) T cells on proliferation and cytokine production of autologous CD4(+) T cells was assessed by flow cytometry. Cultured gut-derived T cells with CD4(+)CD25(+) phenotype expressed FoxP3 and were able as the freshly isolated T(regs) from peripheral blood to suppress proliferation and cytokine production of autologous CD4(+) T cells. Thus, we demonstrate that FoxP3(+)CD4(+)CD25(+) T cells with regulatory properties can be propagated in vitro from inflamed mucosa of CD patients, which may be of interest in adoptive immunotherapy.


Asunto(s)
Linfocitos T CD4-Positivos/inmunología , Colon , Enfermedad de Crohn/inmunología , Proteínas de Unión al ADN/análisis , Mucosa Intestinal/inmunología , Receptores de Interleucina-2/análisis , Adulto , Linfocitos T CD4-Positivos/metabolismo , Estudios de Casos y Controles , Células Cultivadas , Proteínas de Unión al ADN/genética , Regulación hacia Abajo , Femenino , Citometría de Flujo , Factores de Transcripción Forkhead , Humanos , Interferón gamma/inmunología , Interleucina-2/inmunología , Interleucina-4/inmunología , Masculino , ARN Mensajero/análisis , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Factor de Necrosis Tumoral alfa/inmunología
10.
Artículo en Alemán | MEDLINE | ID: mdl-15605297

RESUMEN

We report on a 36 year old patient who collapsed at home and was resuscitated by prehospital medical emergency services. He presented on scene unconscious with severe ST-elevations on the ECG and hardly palpable pulses. His previous medical history included only idiopathic hypertension and his professional background as manager of a company was associated with high stress levels. The prehospital diagnosis was myocardial infarction with cardiogenic shock. A hypovolemic shock was excluded from the differential diagnosis because of the age of the patient, lack of a precipitating trauma and inconsistent symptoms. The patient died after terminating prolonged resuscitation. A post mortem showed as cause of death the rupture of a splenic artery aneurysm. We emphasize that a cardiovascular collapse in a young patient without specific history or trauma still can be caused by hypovolemic shock due to intra-abdominal or -thorac bleeding.


Asunto(s)
Aneurisma Roto/diagnóstico , Bazo/irrigación sanguínea , Enfermedades del Bazo/diagnóstico , Adulto , Diagnóstico Diferencial , Urgencias Médicas , Resultado Fatal , Femenino , Humanos , Resucitación
11.
Clin Exp Immunol ; 138(1): 66-74, 2004 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-15373907

RESUMEN

Integrin alpha4beta 7 is the principal gut-homing receptor, and it is assumed that expression of this specific integrin directs lymphocytes to the gut in vivo. Adoptive cellular immunotherapy against inflammatory bowel disease (IBD) may depend on the expression of integrin alpha4beta 7 to accomplish local delivery of intravenously injected regulatory T cells in inflamed gut mucosa. The present study aimed to investigate whether in vitro expanded human T cells from the colonic mucosa maintain integrin expression, show in vitro adhesion and retain in vivo gut-homing properties during cultivation. Whole colonic biopsies from healthy subjects were cultured in the presence of interleukin-2 (IL-2) and IL-4. The integrin expression of the cultured T cells was determined by flow cytometry and in vitro adhesion was assessed in a mucosal addressin cell adhesion molecule 1 (MAdCAM-1) adhesion assay. We studied the homing pattern after autologous infusion of 3 x 10(8 111)Indium ((111)In)-labelled T cells in five healthy subjects using scintigraphic imaging. The cultured CD4(+)CD45RO(+) gut-derived T cells express higher levels of integrin alpha4beta 7 than peripheral blood lymphocytes (PBLs) and show strong adhesion to MAdCAM-1 in vitro, even after (111)In-labelling. Scintigraphic imaging, however, showed no gut-homing in vivo. After prolonged transit through the lungs, the T cells migrated preferentially to the spleen, liver and bone marrow. In conclusion, it is feasible to infuse autologous T cells cultured from the gut mucosa, which may be of interest in adoptive immunotherapy. Despite high expression of the gut-homing integrin alpha4beta 7 and adhesion to MAdCAM-1 in vitro, evaluation by (111)In-scintigraphy demonstrated no gut-homing in healthy individuals.


Asunto(s)
Colon/inmunología , Inmunoglobulinas/inmunología , Integrinas/análisis , Mucosa Intestinal/inmunología , Mucoproteínas/inmunología , Linfocitos T/inmunología , Adulto , Antígenos CD/inmunología , Médula Ósea/inmunología , Adhesión Celular/inmunología , Moléculas de Adhesión Celular , Movimiento Celular/inmunología , Células Cultivadas , Femenino , Humanos , Radioisótopos de Indio , Integrinas/inmunología , Interleucina-2/inmunología , Interleucina-4/inmunología , Hígado/inmunología , Pulmón/inmunología , Masculino , Persona de Mediana Edad , Receptores Mensajeros de Linfocitos/inmunología , Bazo/inmunología
12.
Eur J Endocrinol ; 150(6): 893-904, 2004 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15191361

RESUMEN

OBJECTIVE: The aim was to investigate the possible interactions of the two peripheral hormones, leptin and ghrelin, that regulate the energy balance in opposite directions. METHODS: Leptin-receptor mutated Zucker diabetic fatty (ZDF) and lean control rats were treated with the ghrelin-receptor ligand, tabimorelin (50 mg/kg p.o.) for 18 days, and the effects on body weight, food intake and body composition were investigated. The level of expression of anabolic and catabolic neuropeptides and their receptors in the hypothalamic area were analysed by in situ hybridization. RESULTS: Tabimorelin treatment induced hyperphagia and adiposity (increased total fat mass and gain in body weight) in lean control rats, while these parameters were not increased in ZDF rats. Treatment with tabimorelin of lean control rats increased hypothalamic mRNA expression of the anabolic neuropeptide Y (NPY) mRNA and decreased hypothalamic expression of the catabolic peptide pro-opiomelanocortin (POMC) mRNA. In ZDF rats, the expression of POMC mRNA was not affected by treatment with tabimorelin, whereas NPY mRNA expression was increased in the hypothalamic arcuate nucleus. CONCLUSION: This shows that tabimorelin-induced adiposity and hyperphagia in lean control rats are correlated with increased hypothalamic NPY mRNA and decreased POMC mRNA expression. The elimination of tabimorelin-induced adiposity and hyperphagia in ZDF rats may be due to lack of POMC mRNA downregulation. In conclusion, we suggest that ghrelin-receptor ligands exert their adipogenic and orexigenic effects via hypothalamic mechanisms that are dependent on intact leptin-receptor signalling.


Asunto(s)
Composición Corporal/efectos de los fármacos , Dipéptidos/farmacología , Ingestión de Alimentos/efectos de los fármacos , Receptores de Superficie Celular/fisiología , Receptores Acoplados a Proteínas G/fisiología , Transducción de Señal , Tejido Adiposo/efectos de los fármacos , Animales , Peso Corporal/efectos de los fármacos , Expresión Génica , Hiperfagia/inducido químicamente , Hipotálamo/química , Hibridación in Situ , Mutación , Neuropéptido Y/genética , Proopiomelanocortina/genética , ARN Mensajero/análisis , Ratas , Ratas Zucker , Receptores de Superficie Celular/genética , Receptores Acoplados a Proteínas G/metabolismo , Receptores de Ghrelina , Receptores de Leptina
13.
J Contam Hydrol ; 61(1-4): 219-33, 2003 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-12598106

RESUMEN

Within the scope of a bilateral cooperation between Svensk Kärnbränslehantering (SKB) and Forschungszentrum Karlsruhe, Institut für Nukleare Entsorgung (FZK-INE), an actinide migration experiment is currently being performed at the Aspö Hard Rock Laboratory (HRL) in Sweden. This paper covers laboratory and in situ investigations on actinide migration in single-fractured granite core samples. For the in situ experiment, the CHEMLAB 2 probe developed by SKB was used. The experimental setup as well as the breakthrough of inert tracers and of the actinides Am, Np and Pu are presented. The breakthrough curves of inert tracers were analyzed to determine hydraulic properties of the fractured samples. Postmortem analyses of the solid samples were performed to characterize the flow path and the sorbed actinides. After cutting the cores, the abraded material was analyzed with respect to sorbed actinides. The slices were scanned optically to visualize the flow path. Effective volumes and inner surface areas were measured. In the experiments, only breakthrough of Np(V) was observed. In each experiment, the recovery of Np(V) was < or = 40%. Breakthrough of Am(III) and Pu(IV) as well as of Np(IV) was not observed.


Asunto(s)
Elementos de Series Actinoides/análisis , Dióxido de Silicio/química , Fenómenos Geológicos , Geología , Alemania , Cooperación Internacional , Residuos Radiactivos , Suecia
14.
Proc Natl Acad Sci U S A ; 100(3): 1438-43, 2003 Feb 04.
Artículo en Inglés | MEDLINE | ID: mdl-12552113

RESUMEN

Glucagon, the counter-regulatory hormone to insulin, is secreted from pancreatic alpha cells in response to low blood glucose. To examine the role of glucagon in glucose homeostasis, mice were generated with a null mutation of the glucagon receptor (Gcgr(-/-)). These mice display lower blood glucose levels throughout the day and improved glucose tolerance but similar insulin levels compared with control animals. Gcgr(-/-) mice displayed supraphysiological glucagon levels associated with postnatal enlargement of the pancreas and hyperplasia of islets due predominantly to alpha cell, and to a lesser extent, delta cell proliferation. In addition, increased proglucagon expression and processing resulted in increased pancreatic glucogen-like peptide 1 (GLP-1) (1-37) and GLP-1 amide (1-36 amide) content and a 3- to 10-fold increase in circulating GLP-1 amide. Gcgr(-/-) mice also displayed reduced adiposity and leptin levels but normal body weight, food intake, and energy expenditure. These data indicate that glucagon is essential for maintenance of normal glycemia and postnatal regulation of islet and alpha and delta cell numbers. Furthermore, the lean phenotype of Gcgr(-/-) mice suggests glucagon action may be involved in the regulation of whole body composition.


Asunto(s)
Glucemia/metabolismo , Glucagón/sangre , Islotes Pancreáticos/patología , Receptores de Glucagón/genética , Receptores de Glucagón/fisiología , Animales , Peso Corporal , Calorimetría , División Celular , AMP Cíclico/metabolismo , Epidídimo/metabolismo , Epinefrina/farmacología , Glucosa/metabolismo , Hormonas/metabolismo , Hiperplasia , Inmunohistoquímica , Insulina/metabolismo , Hígado/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Microscopía Fluorescente , Fenotipo , Factores de Tiempo
15.
Appl Radiat Isot ; 57(5): 687-95, 2002 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-12433043

RESUMEN

Based on a high affinity to the enzyme estrone sulfatase (ES), 16alpha-[18F]fluoroestradiol-3,17beta-disulfamate ([18F]FESDS) has been suggested as a potential PET radiotracer for imaging steroid-dependent breast tumours. The distribution of [18F]FESDS was studied in rats, tumour-bearing nude mice and piglets. In all species evidence for binding to a second target, the enzyme carbonic anhydrase (CA), was obtained. ES and CA inhibitors significantly reduced the radiotracer uptake in various organs but not in tumours. It is concluded that [18F]FESDS binds to ES and CA in vivo but this binding is not strong enough to allow tumour imaging with positron emission tomography (PET).


Asunto(s)
Estradiol/análogos & derivados , Radioisótopos de Flúor , Neoplasias Experimentales/diagnóstico por imagen , Radiofármacos , Animales , Neoplasias de la Mama/diagnóstico por imagen , Estradiol/síntesis química , Estradiol/farmacocinética , Femenino , Radioisótopos de Flúor/farmacocinética , Humanos , Ratones , Ratones Desnudos , Trasplante de Neoplasias , Radiofármacos/síntesis química , Radiofármacos/farmacocinética , Ratas , Ratas Wistar , Porcinos , Distribución Tisular , Tomografía Computarizada de Emisión , Trasplante Heterólogo , Células Tumorales Cultivadas
16.
Environ Sci Technol ; 36(21): 4483-8, 2002 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-12433155

RESUMEN

Groundwater colloids from the Gorleben site (Lower Saxony, Germany) are characterized in the presence of Eu(III) by tapping-mode atomic force microscopy (AFM) with phase contrast imaging. Using a liquid cell the method allows investigations of samples being in contact with aqueous solution. This ensures that complex structures are kept in their native hydrated state. Different types of colloids and aggregates are found by AFM, e.g., spherical particles, fibrous structures, and structures which appear to be hollow. A partial coating of the edges of clay particles with humic colloids can be assumed from phase contrast images. Therefore, aquatic colloids and their aggregates found in Gorleben groundwater can be characterized as a complex mixture of components, which may influence the migration of groundwater contaminants in different processes.


Asunto(s)
Coloides/análisis , Monitoreo del Ambiente/métodos , Contaminantes del Suelo/análisis , Contaminantes del Agua/análisis , Alemania , Sustancias Húmicas/análisis , Microscopía de Fuerza Atómica
17.
Appl Radiat Isot ; 56(6): 773-80, 2002 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-12102332

RESUMEN

16Alpha-fluoroestradiol-3,17beta-disulfamate (FESDS) strongly inhibits estrone sulfatase (ES), an enzyme which is also present in the brain. The enzyme is probably involved in important regulatory functions of neurosteroids which may be disturbed in certain brain diseases. In the present study, [18F]FESDS was used to measure the amount of ES in various rat brain regions using quantitative in vitro autoradiography. The obtained values vary between 0.29 pmol (mg protein)(-1) (pons) and 11.5 pmol (mg protein)(-1) (striatum). They are positively correlated with the enzyme activity measured in homogenates of the corresponding regions. Because this radiotracer binds also to carbonic anhydrase in the brain it is only of limited use for in vivo imaging studies.


Asunto(s)
Encéfalo/enzimología , Estradiol/farmacocinética , Radioisótopos de Flúor , Sulfatasas/metabolismo , Adenocarcinoma , Animales , Autorradiografía/métodos , Neoplasias de la Mama , Estradiol/análogos & derivados , Femenino , Humanos , Cinética , Especificidad de Órganos , Ratas , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Sulfatasas/genética , Transcripción Genética , Células Tumorales Cultivadas
18.
Appl Radiat Isot ; 55(5): 631-9, 2001 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11573796

RESUMEN

After 16alpha-[15F]fluoroestradiol ([18F]FES) has been successfully prepared in an automated module, the synthesis of 16alpha-[18F]fluoroestradiol-3,17beta-disulphamate ([18F]FESDS) is described as a module-assisted one-pot procedure which can provide 10GBq [18F]FESDS with a radiochemical purity better than 99%. The procedure is reliable and reproducible and requires a time of about 90 min. Because of its high sulphatase-inhibitory effect [15F]FESDS is thought to be a new PET tracer to image sites of high sulphatase activity.


Asunto(s)
Estradiol/síntesis química , Radiofármacos/síntesis química , Arilsulfatasas/antagonistas & inhibidores , Inhibidores Enzimáticos/síntesis química , Estradiol/análogos & derivados , Radioisótopos de Flúor , Humanos , Radioquímica/instrumentación , Radioquímica/métodos , Esteril-Sulfatasa , Tomografía Computarizada de Emisión
19.
Endocrine ; 14(1): 63-6, 2001 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11322502

RESUMEN

The growth hormone (GH)/insulin-like growth factor-1 axis is not only of importance for linear body growth during childhood, but it is also one of the major determinants of adult bone mass. Studies show that GH treatment increases bone mass in rodents as well as in adult GH-deficient humans, but the effect of GH treatment on bone mass in healthy humans has so far not been impressive. Recently, a new class of GH secretagogues (GHSs) has been developed. In humans, GHS treatment affects biochemical markers of bone turnover and increases growth velocity in selected short children with or without GH deficiency. In rodents, GHS treatment increase bone mineral content, but it has not yet been shown that GHS treatment can affect bone mass in adult humans.


Asunto(s)
Remodelación Ósea/efectos de los fármacos , Hormona Liberadora de Hormona del Crecimiento/farmacología , Hormona del Crecimiento/farmacología , Hormonas/farmacología , Hormonas Peptídicas , Adulto , Factores de Edad , Animales , Desarrollo Óseo/efectos de los fármacos , Resorción Ósea/fisiopatología , Huesos/anatomía & histología , Huesos/efectos de los fármacos , Ghrelina , Hormona del Crecimiento/deficiencia , Humanos , Indoles/farmacología , Oligopéptidos/farmacología , Tamaño de los Órganos , Péptidos/farmacología , Compuestos de Espiro/farmacología
20.
J Leukoc Biol ; 69(3): 397-404, 2001 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11261786

RESUMEN

Organisms belonging to the Mycobacterium avium complex (MAC) cause life-threatening bacteremia in immunocompromised patients. Monocytes and macrophages are thought to be responsible for ingestion and killing of MAC. However, it has been suggested that neutrophils may play a role in the early immune response to MAC infection. Here, neutrophils in autologous plasma were incubated (at 0 and 37 degrees C) with M. avium labeled with Auramine O, a potent fluorochrome. Neutrophil phagocytosis was measured by flow cytometry. Neutrophils incubated at 37 degrees C showed an increase in fluorescence over time with a maximum at 15 min, whereas neutrophils on ice showed no time-dependent increase in FL1. At 15 min Fl 1 at 37 degrees C was twice as high as FL1 at 0 degrees C. Examination under the fluorescent microscope showed multiple intracellular fluorescent mycobacteria. Results in nine independent experiments showed time-dependent decrease of colony-forming units in neutrophil-associated live M. avium. Significant killing was observed within 30 min and was complete by 120 min. Observation by electron microscopy clearly confirmed the presence of intraphagosomal MAC, both intact and with evidence of degradation. These data demonstrate that MAC is rapidly phagocytized and killed by human neutrophils. The newly established flow cytometry method should be useful in further studies of neutrophil function and of the role of G-CSF and other cytokines in MAC disease.


Asunto(s)
Complejo Mycobacterium avium/inmunología , Neutrófilos/inmunología , Fagocitosis/inmunología , Adulto , Benzofenoneido , Sedimentación Sanguínea , Colorantes , Citotoxicidad Inmunológica , Femenino , Citometría de Flujo , Humanos , Masculino , Microscopía Electrónica , Microscopía Fluorescente
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...