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1.
Sci Adv ; 7(16)2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33863726

RESUMO

Dislocations are one-dimensional defects in crystals, enabling their deformation, mechanical response, and transport properties. Less well known is their influence on material chemistry. The severe lattice distortion at these defects drives solute segregation to them, resulting in strong, localized spatial variations in chemistry that determine microstructure and material behavior. Recent advances in atomic-scale characterization methods have made it possible to quantitatively resolve defect types and segregation chemistry. As shown here for a Pt-Au model alloy, we observe a wide range of defect-specific solute (Au) decoration patterns of much greater variety and complexity than expected from the Cottrell cloud picture. The solute decoration of the dislocations can be up to half an order of magnitude higher than expected from classical theory, and the differences are determined by their structure, mutual alignment, and distortion field. This opens up pathways to use dislocations for the compositional and structural nanoscale design of advanced materials.

2.
Sci Adv ; 7(11)2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33712466

RESUMO

Glucose-dependent insulinotropic polypeptide (GIP) communicates nutrient intake from the gut to islets, enabling optimal levels of insulin secretion via the GIP receptor (GIPR) on ß cells. The GIPR is also expressed in α cells, and GIP stimulates glucagon secretion; however, the role of this action in the postprandial state is unknown. Here, we demonstrate that GIP potentiates amino acid-stimulated glucagon secretion, documenting a similar nutrient-dependent action to that described in ß cells. Moreover, we demonstrate that GIP activity in α cells contributes to insulin secretion by invoking paracrine α to ß cell communication. Last, specific loss of GIPR activity in α cells prevents glucagon secretion in response to a meal stimulus, limiting insulin secretion and driving glucose intolerance. Together, these data uncover an important axis by which GIPR activity in α cells is necessary to coordinate the optimal level of both glucagon and insulin secretion to maintain postprandial homeostasis.


Assuntos
Diabetes Mellitus Tipo 2 , Incretinas , Polipeptídeo Inibidor Gástrico , Glucagon , Glucose , Humanos , Receptores Acoplados a Proteínas G , Receptores dos Hormônios Gastrointestinais
3.
Eur J Health Econ ; 19(9): 1243-1257, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29680926

RESUMO

BACKGROUND: Multiple sclerosis (MS) imposes high economic costs on society, but the patients and their families have to bear some of these costs. OBJECTIVE: We aimed to estimate the magnitude of these economic costs in Norway. METHOD: We collected data through a postal questionnaire survey targeting 922 MS patients in Hordaland County, western Norway, in 2013-2014; 546 agreed to participate and were included. The questionnaire included clinical and demographic characteristics, volume and cost of MS-related resource use, work participation, income, government financial support, and disability status. RESULTS: The mean annual total economic costs for the patients and their families were €11,603. Indirect costs accounted for 66% and were lower for women than for men. The direct costs were nearly identical for men and women. The costs increased up to Expanded Disability Status Scale score 6 except for steps between 3 and 4 where it remained nearly constant. The costs reduced from EDSS 6 to 8, and increased from 8 to 9. Lifetime costs ranged from €24,897 to €70,021 for patients with late disease onset and slow progression, and between €441,934 and €574,860 for patients with early onset and rapid progression. CONCLUSION: The economic costs of MS impose a heavy burden on the patients and their families. Supplementing the information on the cost of MS to society, our finding should be included as background information in decisions on reimbursing and allocating public resources for the well-being of MS patients and their families.


Assuntos
Efeitos Psicossociais da Doença , Saúde da Família/economia , Gastos em Saúde/estatística & dados numéricos , Esclerose Múltipla/economia , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Econométricos , Noruega , Inquéritos e Questionários
4.
Biochem Pharmacol ; 131: 78-88, 2017 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-28237651

RESUMO

Alternative processing of the precursor protein pro-GIP results in endogenously produced GIP(1-30)NH2, that by DPP-4 cleavage in vivo results in the metabolite GIP(3-30)NH2. We showed previously that GIP(3-30)NH2 is a high affinity antagonist of the human GIPR in vitro. Here we determine whether it is suitable for studies of GIP physiology in rats since effects of GIP agonists and antagonists are strictly species-dependent. Transiently transfected COS-7 cells were assessed for cAMP accumulation upon ligand stimulation or assayed in competition binding using human 125I-GIP(1-42) as radioligand. In isolated perfused rat pancreata, insulin, glucagon, and somatostatin-releasing properties were evaluated. Competition binding demonstrated that on the rat GIP receptor (GIPR), rat GIP(3-30)NH2 bound with high affinity (Ki of 17nM), in contrast to human GIP(3-30)NH2 (Ki of 250nM). In cAMP studies, rat GIP(3-30)NH2 inhibited GIP(1-42)-induced rat GIPR activation and schild-plot analysis showed competitive antagonism with a pA2 of 13nM and a slope of 0.9±0.09. Alone, rat GIP(3-30)NH2 displayed weak, low-potent partial agonistic properties (EC50>1µM) with an efficacy of 9.4% at 0.32µM compared to GIP(1-42). In perfused rat pancreata, rat GIP(3-30)NH2 efficiently antagonized rat GIP(1-42)-induced insulin, somatostatin, and glucagon secretion. In summary, rat GIP(3-30)NH2 is a high affinity competitive GIPR antagonist and effectively antagonizes GIP-mediated G protein-signaling as well as pancreatic hormone release, while human GIP(3-30)NH2, despite a difference of only one amino acid between the two (arginine in position 18 in rat GIP(3-30)NH2; histidine in human), is unsuitable in the rat system. This underlines the importance of species differences in the GIP system, and the limitations of testing human peptides in rodent systems.


Assuntos
Polipeptídeo Inibidor Gástrico/fisiologia , Glucagon/metabolismo , Insulina/metabolismo , Fragmentos de Peptídeos/farmacologia , Receptores dos Hormônios Gastrointestinais/antagonistas & inibidores , Somatostatina/metabolismo , Sequência de Aminoácidos , Animais , Células COS , Chlorocebus aethiops , Polipeptídeo Inibidor Gástrico/química , Polipeptídeo Inibidor Gástrico/farmacologia , Humanos , Secreção de Insulina , Masculino , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/fisiologia , Ratos , Ratos Wistar , Homologia de Sequência de Aminoácidos
5.
Br J Pharmacol ; 173(1): 27-38, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26359804

RESUMO

BACKGROUND AND PURPOSE: Specific, high potency receptor antagonists are valuable tools when evaluating animal and human physiology. Within the glucose-dependent, insulinotropic polypeptide (GIP) system, considerable attention has been given to the presumed GIP receptor antagonist, (Pro3)GIP, and its effect in murine studies. We conducted a pharmacological analysis of this ligand including interspecies differences between the rodent and human GIP system. EXPERIMENTAL APPROACH: Transiently transfected COS-7 cells were assessed for cAMP accumulation upon ligand stimulation and assayed in competition binding using (125) I-human GIP. Using isolated perfused pancreata both from wild type and GIP receptor-deficient rodents, insulin-releasing, glucagon-releasing and somatostatin-releasing properties in response to species-specific GIP and (Pro3)GIP analogues were evaluated. KEY RESULTS: Human (Pro3)GIP is a full agonist at human GIP receptors with similar efficacy (Emax ) for cAMP production as human GIP, while both rat and mouse(Pro3)GIP were partial agonists on their corresponding receptors. Rodent GIPs are more potent and efficacious at their receptors than human GIP. In perfused pancreata in the presence of 7 mM glucose, both rodent (Pro3)GIP analogues induced modest insulin, glucagon and somatostatin secretion, corresponding to the partial agonist activities observed in cAMP production. CONCLUSIONS AND IMPLICATIONS: When evaluating new compounds, it is important to consider interspecies differences both at the receptor and ligand level. Thus, in rodent models, human GIP is a comparatively weak partial agonist. Human (Pro3)GIP was not an antagonist at human GIP receptors, so there is still a need for a potent antagonist in order to elucidate the physiology of human GIP.


Assuntos
Agonismo Parcial de Drogas , Polipeptídeo Inibidor Gástrico/farmacologia , Receptores dos Hormônios Gastrointestinais/agonistas , Receptores dos Hormônios Gastrointestinais/antagonistas & inibidores , Animais , Ligação Competitiva/efeitos dos fármacos , Células COS , Chlorocebus aethiops , AMP Cíclico/metabolismo , Relação Dose-Resposta a Droga , Polipeptídeo Inibidor Gástrico/análogos & derivados , Glucagon/metabolismo , Humanos , Insulina/metabolismo , Radioisótopos do Iodo/metabolismo , Masculino , Camundongos , Pâncreas/metabolismo , Ensaio Radioligante , Ratos , Somatostatina/metabolismo , Especificidade da Espécie
6.
Horm Metab Res ; 47(7): 537-43, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25602348

RESUMO

TLQP-21 is a VGF-derived neuropeptide proposed to be involved in regulation of metabolism. More specifically it has been suggested that TLQP-21 has the ability to enhance glucose stimulated insulin secretion, making it a candidate for treatment of patients with type 2 diabetes.In this study, we investigated the impact of TLQP-21 on insulin, glucagon, and somatostatin secretion in the perfused rat pancreas. We found that administration of 5 and 50 nM TLQP-21 had no impact on pancreatic hormone secretion at 3.5 or 8 mM glucose levels. Increasing TLQP-21 (200 nM) and glucose concentration (3.5 and 16 mM) led to a nonsignificant decrease in glucagon secretion, though insulin and somatostatin secretory patterns remained unaffected. In a final set of experiments, perfusions were performed with infusion of 50 and 1 000 nM TLQP-21 to ensure sufficient stimulation. However, administration of TLQP-21 under this setup showed no impact on the pancreatic hormone secretion either. In conclusion, the outcome of this study does not concur with previous findings, suggesting that the effect of TLQP-21 does not directly involve silent hormone secretion.


Assuntos
Glucagon/metabolismo , Insulina/metabolismo , Pâncreas/efeitos dos fármacos , Fragmentos de Peptídeos/farmacologia , Somatostatina/metabolismo , Animais , Glucose/farmacologia , Secreção de Insulina , Masculino , Pâncreas/metabolismo , Ratos , Ratos Wistar
7.
Eur J Health Econ ; 13(1): 81-91, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21080024

RESUMO

Health economic aspects have been increasingly important during introduction of new treatments for multiple sclerosis. As a partial response for Norway, a cost-of-illness study was carried out to estimate the yearly cost of the illness to society and relate costs and patients' quality of life to illness severity. Estimated cost to society was Euro 439 million in 2002 exclusive of the cost of reduced quality of life. The cost per patient was close to Euro 65,000. Account taken of methodological differences, the results compare to results for Sweden, Norway's closest neighboring country. The illness reduced patients' quality of life with 0.26. More patients were early retired because of their MS in Norway than in any of nine other European countries comprised by a recent European study, illustrating a liberal practice in Norway. The Norwegian cost of unpaid assistance was almost identical to the Swedish cost that was the lowest found across the countries in the European study. When related to illness severity, the cost per patient increased, and the patients' experienced quality of life decreased with increasing EDSS levels in line with what has been found for other countries. Cost-of-MS studies have been carried out for a number of countries. Together they contribute to our understanding of the economic consequences of multiple sclerosis and, if their results are related to illness severity, also provide valuable information for further economic analyses of treatment and medication. Our study adds to this.


Assuntos
Esclerose Múltipla/economia , Adulto , Efeitos Psicossociais da Doença , Custos e Análise de Custo/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Noruega , Qualidade de Vida , Inquéritos e Questionários
8.
Diabetes Obes Metab ; 13 Suppl 1: 89-94, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21824261

RESUMO

Glucagon secretion plays an essential role in the regulation of hepatic glucose production, and elevated fasting and postprandial plasma glucagon concentrations in patients with type 2 diabetes (T2DM) contribute to their hyperglycaemia. The reason for the hyperglucagonaemia is unclear, but recent studies have shown lack of suppression after oral but preserved suppression after isoglycaemic intravenous glucose, pointing to factors from the gut. Gastrointestinal hormones that are secreted in response to oral glucose include glucagon-like peptide-1 (GLP-1) that strongly inhibits glucagon secretion, and GLP-2 and GIP, both of which stimulate secretion. When the three hormones are given together on top of isoglycaemic intravenous glucose, glucagon suppression is delayed in a manner similar to that observed after oral glucose. Studies with the GLP-1 receptor antagonist, exendin 9-39, suggest that endogenous GLP-1 plays an important role in regulation of glucagon secretion during fasting as well as postprandially. The mechanisms whereby GLP-1 regulates glucagon secretion are debated, but studies in isolated perfused rat pancreas point to an important role for a paracrine regulation by somatostatin from neighbouring D cells. Clinical studies of the antidiabetic effect of GLP-1 in T2DM suggest that the inhibition of glucagon secretion is as important as the stimulation of insulin secretion.


Assuntos
Diabetes Mellitus Tipo 2/metabolismo , Peptídeo 1 Semelhante ao Glucagon/metabolismo , Glucagon/metabolismo , Incretinas/metabolismo , Receptores de Glucagon/metabolismo , Animais , Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/fisiopatologia , Peptídeo 1 Semelhante ao Glucagon/farmacologia , Receptor do Peptídeo Semelhante ao Glucagon 1 , Humanos , Ratos
9.
J Athl Train ; 31(3): 197, 1996 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16558398
10.
Leukemia ; 10(2): 327-32, 1996 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8637242

RESUMO

In 18 cases of monoclonal gammopathy of undetermined significance, MGUS (monoclonal gammopathy of undetermined significance), admitted for diagnosed or suspected peripheral neuropathy, 11 patients showed other co-existing autoimmune manifestations. Two had POEMS syndrome (polyneuropathy, organomegaly, endocrinopathy, M-component, and skin symptoms), the others mainly endocrinopathy and polyclonal pseudolymphoma. There were 13 cases of sensorimotor neuropathy, two cases of neuritis, while neuropathy could not be confirmed in three cases. Compared with a retrospective review of autoimmunity in a randomly selected CLL (chronic lymphocytic leukemia) cohort of 115 patients, 13 out of 42 patients with clinical and/or laboratory features of autoimmunity showed co-expression of autoimmune signs, the dominating traits being Coombs positive AIHA (auto-immune hemolytic anemia), platelet autoantibodies, endocrinopathy mainly associated with the thyroid gland, serological and/or rheumatological symptoms, but only one case of sensorimotor neuropathy. Viewed from a current model of acquired autoimmunity it is perhaps not surprising that such autoimmunity is seen predominantly in patients with monoclonal gammopathy. Thus, a high concentration of cross-reacting polyreactive autoantibodies related to the M-component might be present in these patients. Furthermore, quantitative defects of the immunoglobulins including the hypogammaglobulinemia associated with M-components can presumably give rise to a defect of the anti-idiotypic network's regulation of natural autoantibodies and autoimmune manifestations in vivo. Such autoimmune manifestations, which are easily overlooked in CLL may call for additional treatment with immunosuppression and/or intravenous, polyclonal IgG.


Assuntos
Doenças Autoimunes/etiologia , Leucemia Linfocítica Crônica de Células B/complicações , Paraproteinemias/etiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Anti-Idiotípicos/metabolismo , Doenças Autoimunes/imunologia , Autoimunidade , Feminino , Humanos , Leucemia Linfocítica Crônica de Células B/imunologia , Masculino , Pessoa de Meia-Idade , Síndrome POEMS/etiologia , Síndrome POEMS/imunologia , Paraproteinemias/imunologia
11.
Fertil Steril ; 56(3): 540-6, 1991 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-1894034

RESUMO

OBJECTIVE: We compared the pregnancy rates (PRs) after intrauterine insemination (IUI) with frozen donor sperm prepared in Ham's F-10 medium (Irvine Scientific, Santa Ana, CA) with bicarbonate buffer and synthetic human tubal fluid with HEPES buffer (Irvine Scientific). DESIGN: Women (n = 101) were randomized upon entry into the program, receiving sperm prepared in either Ham's F-10 or human tubal fluid medium their first treatment cycle. If pregnancy did not occur, the alternate medium was used to prepared sperm for the following cycle. SETTING: All patients were treated in our private care center. PATIENTS: Patients entering this study were normally ovulating women undergoing IUI with frozen donor sperm. MAIN OUTCOME MEASURE: Pregnancy was used as our main outcome measure of success. RESULTS: After 324 cycles of treatment, the PR per cycle of IUI was 17.5% with sperm prepared in human tubal fluid which was significantly different (P = 0.05) from the PR (9.8%) after insemination with sperm prepared in Ham's F-10. There was no statistical difference in the number of motile cells inseminated in each of these groups. CONCLUSIONS: Transitory exposure of the sperm in Ham's F-10 medium to the environment during preparation for insemination may result in an alkalinization of the medium that has a lasting influence on sperm fertility.


Assuntos
Bicarbonatos/farmacologia , Criopreservação , HEPES/farmacologia , Inseminação Artificial Heteróloga , Gravidez/efeitos dos fármacos , Espermatozoides , Soluções Tampão , Meios de Cultura , Feminino , Humanos , Hormônio Luteinizante/urina , Masculino , Estudos Prospectivos , Motilidade dos Espermatozoides , Fatores de Tempo
12.
Mutat Res ; 255(2): 163-73, 1991 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-1922148

RESUMO

Over 10-fold larger fluences were required to inhibit both DNA synthesis and cell division in wild-type C. elegans embryos as compared with other model systems or C. elegans rad mutants. In addition, unlike in other organisms, the molecular weight of daughter DNA strands was reduced only after large, superlethal fluences. The molecular weight of nascent DNA fragments exceeded the interdimer distance by up to 19-fold, indicating that C. elegans embryos can replicate through non-instructional lesions. This putative trans-lesion synthetic capability may explain the refractory nature of UV radiation on embryonic DNA synthesis and nuclear division in C. elegans.


Assuntos
Caenorhabditis/genética , DNA/biossíntese , Raios Ultravioleta , Animais , Caenorhabditis/embriologia , Caenorhabditis/efeitos da radiação , Divisão Celular , DNA/efeitos da radiação , Dano ao DNA , Microscopia de Fluorescência , Mutação
13.
Science ; 236(4798): 181-2, 1987 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-17789782

RESUMO

The melting curve of iron, the primary constituent of Earth's core, has been measured to pressures of 250 gigapascals with a combination of static and dynamic techniques. The melting temperature of iron at the pressure of the core-mantle boundary (136 gigapascals) is 4800 +/- 200 K. whereas at the inner core-outer core boundary (330 gigapascals), it is 7600 +/- 500 K. Corrected for melting point depression resulting from the presence of impurities, a melting temperature for iron-rich alloy of 6600 K at the inner core-outer core boundary and a maximum temperature of 6900 K at Earth's center are inferred. This latter value is the first experimental upper bound on the temperature at Earth's center, and these results imply that the temperature of the lower mantle is significantly less than that of the outer core.

17.
Acta Psychiatr Scand ; 55(3): 161-4, 1977 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-848330

RESUMO

In Scandinavia during the past decade forensic psychiatry has been the subject of discussions, which have occasionally reached the height of vehement attacks. Changes in penal laws have expressed a declining interest in the cooperation of psychiatrists in the evaluation and treatment of offenders. Scandinavian forensic psychiatrists, lawyers and criminologists have analyzed and discussed the present situation and have found that there is still a need and justification for forensic psychiatry. Higher priority, however, should be given to psychiatric contributions at the stage after disposition, at the post-trial level. The diagnostic activities at the pre-trial level should be limited to what is necessary for further dispositions. The development of forensic (penal) psychiatry and the trends with the individual Scandinavian countries differ considerably.


Assuntos
Psiquiatria Legal , Previsões , Opinião Pública , Países Escandinavos e Nórdicos , Ajustamento Social , Mudança Social
18.
Acta Psychiatr Scand ; 55(3): 165-75, 1977 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-848331

RESUMO

An attempt is made to give a description of the functions of forensic psychiatry in the Scandinavian countries, including some statistical information on activities and persons involved. Definitions are given. Organizational differences in preparing psychiatric reports to the court in the five countries are outlined, as are the ways in which psychiatrists participate at the post-trial level. Some problems and divergent trends are mentioned. It is concluded that a demand for psychiatric evaluation and treatment of offenders who are psychotic or moderately and more severely mentally retarded will continue to exist, whereas it seems unclear how psychiatrists should deal with the psychiatric problems of offenders with other mental abnormalities. Forensic psychiatric research should include analysis of the functions of this discipline (frequency studies, studies of content, organization and effect).


Assuntos
Psiquiatria Legal , Assistência Ambulatorial , Atitude Frente a Saúde , Previsões , Hospitais Psiquiátricos , Humanos , Legislação como Assunto , Prisões , Países Escandinavos e Nórdicos , Serviço Social em Psiquiatria
19.
Acta Psychiatr Scand ; 55(3): 176-80, 1977 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-848332

RESUMO

In Denmark the desire for psychiatric cooperation within the juridical system has on the whole been on the decline during the past decades. This applies both to the writing of psychiatric reports to the court, and to the sanction system. Within civil forensic psychiatry, practice is almost unchanged and unchallenged, while the demand for one form of social forensic psychiatry has been drastically reduced with the literalization of abortion and sterilization laws. The present practice of penal forensic psychiatry is described. Remarks on the future organization and research are made.


Assuntos
Psiquiatria Legal , Crime , Dinamarca , Previsões , Humanos , Mudança Social
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