RESUMO
Transitions from the liquid to the solid state of matter are omnipresent. They form a crucial step in the industrial solidification of metallic alloy melts and are greatly influenced by the thermophysical properties of the melt. Knowledge of the thermophysical properties of liquid metallic alloys is necessary in order to gain a tight control over the solidification pathway, and over the obtained material structure of the solid. Measurements of thermophysical properties on ground are often difficult, or even impossible, since liquids are strongly influenced by earth's gravity. Another problem is the reactivity of melts with container materials, especially at high temperature. Finally, deep undercooling, necessary to understand nucleus formation and equilibrium as well as non-equilibrium solidification, can only be achieved in a containerless environment. Containerless experiments in microgravity allow precise benchmark measurements of thermophysical properties. The electromagnetic levitator ISS-EML on the International Space Station (ISS) offers perfect conditions for such experiments. This way, data for process simulations is obtained, and a deeper understanding of nucleation, crystal growth, microstructural evolution, and other details of the transformation from liquid to solid can be gained. Here, we address the scientific questions in detail, show highlights of recent achievements, and give an outlook on future work.
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Type 2 diabetes mellitus (T2DM) increases cardiovascular complications. Diabetic vascular dysfunction is associated with the reduced activity of the different smooth muscle potassium (K+) channels. Thus, the objective of our study was to investigate the role of the adenosine triphosphate (ATP)-sensitive K+ (KATP) channels in the relaxant effect of potassium channel opener, pinacidil on the human saphenous vein (HSV) obtained from the patients with and without T2DM. The rings of HSV without the endothelium, obtained from the patients who had undergone coronary bypass surgery, were mounted in an organ bath system and isometric tension was recorded. The relaxation of HSV, precontracted with phenylephrine, was produced by pinacidil. The expression of KATP subunits (Kir6.1, Kir6.2 and SUR2B) was detected by immunohistochemistry and Western blot. Pinacidil produces comparable effects on HSV in patients with and without T2DM. The suppression of pinacidil effect and its maximal relaxation by glibenclamide, selective blocker of KATP channels, was more pronounced on HSV in patients without T2DM. All three types of KATP subunits are expressed on the smooth muscle cells of HSV. While there are no differences in the expression of Kir6.1 and Kir6.2, the expression of SUR2B is lower in HSV in patients with T2DM. Pinacidil produced comparable KATP-dependent and -independent relaxation of the HSV in patients with/without T2DM. According to the effect of glibenclamide and the applied molecular analysis, presented findings demonstrated that diabetes mellitus was associated with the reduced expression of SUR2B subunit in the vascular smooth muscle of HSV.
Assuntos
Diabetes Mellitus Tipo 2/metabolismo , Canais KATP/metabolismo , Pinacidil/farmacologia , Veia Safena/efeitos dos fármacos , Vasodilatação/efeitos dos fármacos , Vasodilatadores/farmacologia , Idoso , Diabetes Mellitus Tipo 2/fisiopatologia , Relação Dose-Resposta a Droga , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Técnicas de Cultura de Órgãos , Veia Safena/fisiologia , Vasodilatação/fisiologiaRESUMO
BACKGROUND: Stent-assisted coiling of intracranial aneurysms is an efficient alternative treatment to surgical clipping but requires prolonged antiplatelet therapy. Some patients are non-responsive to aspirin and/or clopidogrel. OBJECTIVE: To analyze the implications of this assessment using the 'whole blood aggregometry (WBA) by impedance' technique. MATERIALS AND METHODS: The Southwestern Tertiary Aneurysm Registry was reviewed between 2002 and 2012 for patients with unruptured aneurysms treated with stent-assisted coiling. The study population was divided into patients who were tested preoperatively for platelet responsiveness to aspirin and clopidogrel ('tested' patients) and those who were not ('non-tested'). Where necessary, tested patients received additional doses of antiplatelet drugs to achieve adequate platelet inhibition. Endpoints included the incidence of non-responsiveness, the rates of thrombotic and hemorrhagic complications, and the rates of permanent morbidity and mortality. RESULTS: A total of 266 patients fulfilled our selection criteria: 114 non-tested patients who underwent 121 procedures, and 152 tested patients who underwent 171 procedures. The two groups did not vary significantly in patient age, gender, and aneurysms location. Aspirin non-responsiveness was detected in 3 patients (1.75%) and clopidogrel non-responsiveness in 21 patients (12.3%). Non-tested patients had an 11.6% rate of thrombotic complications with a 4.1% permanent morbidity or mortality rate versus 2.3% and 0.6% in tested patients (p=0.0013). The incidence of hemorrhagic complications was similar between the two groups. CONCLUSIONS: Preoperative platelet inhibition testing using WBA can be useful to assess and correct antiaggregant non-responsiveness, and may reduce postoperative mortality and permanent morbidity.
Assuntos
Plaquetas/efeitos dos fármacos , Procedimentos Endovasculares/métodos , Aneurisma Intracraniano/terapia , Inibidores da Agregação Plaquetária/administração & dosagem , Agregação Plaquetária/efeitos dos fármacos , Stents , Idoso , Aspirina/administração & dosagem , Plaquetas/fisiologia , Clopidogrel , Gerenciamento Clínico , Feminino , Humanos , Aneurisma Intracraniano/sangue , Masculino , Pessoa de Meia-Idade , Agregação Plaquetária/fisiologia , Sistema de Registros , Estudos Retrospectivos , Stents/efeitos adversos , Ticlopidina/administração & dosagem , Ticlopidina/análogos & derivadosRESUMO
The ideal agent for prevention and treatment of uterine abnormal contractility has not been found. The polyphenol resveratrol possesses a wide spectrum of pharmacologic properties, but its influence on the contractility of human myometrium is not defined. The present study evaluated the effect of resveratrol on the oxytocin-induced contractions of human term pregnant myometrium in vitro and the contribution of different K(+) channels to resveratrol action. Resveratrol induced a concentration-dependent relaxation of myometrium contractions (pD2 value and maximal responses were 4.52 and 82.25%, respectively). Glibenclamide, a selective blocker of ATP-sensitive (KATP), iberiotoxin, a selective blockers of big-calcium sensitive (BK(Ca)) and 4-aminopiridine, a non-selective blocker of voltage-sensitive (Kv) channels induced a significant shift to the right of the concentration-response curves of resveratrol. Inhibition achieved by 0.1 mM resveratrol was insensitive to all K(+) channel blockers. A K(+) channel opener, pinacidil, inhibited oxytocin-induced contractions of pregnant myometrium with comparable potency and efficacy to resveratrol (pD2 values and maximal relaxation were 4.52 and 83.67%, respectively). Based on K(+) channel opener/blocker affinities, it appears that the inhibitory response of resveratrol involves different myometrial K(+) channels. When applied in high concentrations, resveratrol has an additional K(+)-channel-independent mechanism(s) of action. Furthermore, immunohistochemistry staining and western blot analyses detected the presence and distribution of KATP, BK(Ca) and Kv channel proteins in pregnant myometrium.
Assuntos
Miométrio/efeitos dos fármacos , Pinacidil/farmacologia , Estilbenos/farmacologia , Contração Uterina/efeitos dos fármacos , Feminino , Humanos , Técnicas In Vitro , Ocitocina/farmacologia , Canais de Potássio/metabolismo , Gravidez , ResveratrolRESUMO
This study was aimed to evaluate resveratrol (1-100 µM) effect on the spontaneous rhythmic contractions (SRC), oxytocin-induced (0.2 nM, POxC) phasic and tonic (20 nM, TOxC) contractions of isolated rat uterus. The SRC and POxC were more sensitive to resveratrol than TOxC (pD2 values: 4.53 and 4.66 versus 4.06). Different blockers of K(+) channels (glibenclamide, tetraethylamonium, iberiotoxin, 4-aminopyridine) antagonized the response to resveratrol on the SRC and phasic contractions, but did not antagonize the effect of resveratrol on the TOxC. In order to compare the relaxant activities of resveratrol on the TOxC with that of potassium channel openers, a separate experiments with NS 1619, a highly specific big Ca(2+)-sensitive K(+) (BKCa) channels opener and pinacidil, a predominant opener of ATP-sensitive K(+) (KATP) channels were done. NS 1619 (10-100 µM) and pinacidil (10-100 µM) produced more potent inhibition of TOxC than resveratrol (pD2 values were 6.00 and 5.29). Iberiotoxin, a highly selective BKCa channels blocker, antagonized the response to NS 1619 and glibenclamide, a highly selective KATP channels blocker, antagonized the response to pinacidil on the TOxC. To test K(+)- and extracellular Ca(2+)- independent mechanism(s) of resveratrol on TOxC, a K(+)-rich, Ca(2+)-free solution was used. Under this condition, only high concentrations (≥30 µM) of resveratrol inhibited TOxC. Western blots analysis confirmed expression of Kir6.1, Kir6.2, KCa1.1, Kv2.1 and Kv4.2. channel proteins in myometrium. Thus, the effect of resveratrol is dependent on the types of contractions. The inhibitory response of resveratrol on the SRC and phasic contractions involves different myometrial K(+)- channels. When applied in high concentrations, resveratrol has an additional K(+)- channels independent mechanism(s) of action. As the effects of NS 1619, pinacidil and resveratrol on the TOxC are different, we can conclud that resveratrol does not behave as a classical potassium channel opener.
Assuntos
Contração Isométrica/efeitos dos fármacos , Canais de Potássio/fisiologia , Estilbenos/farmacologia , Útero/efeitos dos fármacos , 4-Aminopiridina/farmacologia , Animais , Benzimidazóis/farmacologia , Feminino , Glibureto/farmacologia , Músculo Liso/efeitos dos fármacos , Músculo Liso/fisiologia , Ocitocina/farmacologia , Peptídeos/farmacologia , Pinacidil/farmacologia , Bloqueadores dos Canais de Potássio/farmacologia , Ratos , Ratos Wistar , Resveratrol , Tetraetilamônio/farmacologia , Útero/fisiologiaRESUMO
BACKGROUND AND PURPOSE: Hypothermia has been shown to be beneficial in the setting of acute SCI. However, widespread use has been hindered by the need for systemic hypothermia as the vehicle for achieving spinal cord hypothermia. This study demonstrates that localized spinal cord hypothermia can be achieved via a percutaneous approach while maintaining systemic normothermia. MATERIALS AND METHODS: Five Yucatan swine underwent catheterization of the subarachnoid space and infusion of room temperature, chilled, and iced PL solutions into the cervical spinal canal, with drainage from the lumbar canal. Thermocouples were placed within the spinal cord and in the subarachnoid space and recorded during infusions and recovery from hypothermia. RESULTS: Results demonstrated that hypothermia as low as 16.8°C is feasible in the spinal cord with retention of systemic normothermia, with strong (r = 0.95) correlation between the spinal cord temperature and the CSF temperature. Degrees of cooling varied with flow rates and with infusate temperature. CONCLUSIONS: While the data are preliminary in a small group of animals, the ability to rapidly create a wide range of controlled spinal cord hypothermia while preserving normal body temperature warrants wider exploration. The study also indicates that further investigation of the hypothesis that CSF temperature monitoring may be an acceptable surrogate for direct spinal cord temperature monitoring should be pursued.
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Temperatura Corporal/fisiologia , Hipotermia Induzida/métodos , Medula Espinal/fisiologia , Animais , SuínosRESUMO
Our aim was to define how different chemical properties of newly developed phenylpropiophenone derivates (PhPds) influenced their potency and efficacy to relax rat aorta. A contribution of ion channels in the PhPds and propafenone mechanism of vasodilatation was tested. PhPds were syntethysed by substitution in the benzyl moiety with -F, -CH3 or -CF3 groups on the ortho or para position. The vasodilatation by PhPds was examined on the rings of rat aorta precontracted with phenylephrine. In order to test involvement of voltage-gated Na+ and K+ channels and L-type Ca2+ channels in a mechanism of action of PhPds, we used their blockers: lidocaine, nifedipine and 4-aminopiridine, respectively. Aorta was more sensitive to 5-ortho-trifluoromethyl derivate than to propafenone and other PhPds. The 5-para-methyl derivate had lower potency and efficacy than propafenone and other PhPds. Lidocaine did not influenced relaxation induced by PhPds, but slightly inhibited the effect of propafenone. The 4-aminopiridine only inhibited relaxation induced by 5-para-methyl derivate. Nifedipine inhibited relaxation of the rat aorta induced by 5-ortho-trifluoromethyl derivate and by propafenone. Introduction of 5-ortho-trifluoromethyl and 5-para-methyl group in the benzyl moiety of propafenone molecule changed its potency, efficacy and mechanism of action in the rat aorta. The 4-aminopiridine- and nifedipine sensitive ion channels are involved in mechanism of action of 5-para-methyl and 5-ortho-trifluoromethyl derivate. The introduction of other tested groups in the benzyl moiety does not affect pharmacological properties of the PhPds in relation to propafenone.
Assuntos
Aorta/efeitos dos fármacos , Propiofenonas/farmacologia , Vasodilatação/efeitos dos fármacos , Animais , Aorta/fisiologia , Técnicas In Vitro , Lidocaína/farmacologia , Masculino , Nifedipino/farmacologia , Fenilefrina/farmacologia , Propafenona/farmacologia , Ratos , Ratos Wistar , Relação Estrutura-AtividadeRESUMO
The energetics of mixing and structural arrangement in liquid Al-Cr and Cr-Ni alloys has been analysed through the study of surface properties (surface tension and surface segregation), dynamic properties (chemical diffusion) and microscopic functions (concentration fluctuations in the long-wavelength limit and chemical short-range order parameter) in the framework of statistical mechanical theory in conjunction with quasi-lattice theory. The Al-Cr phase diagram exhibits the existence of different intermetallic compounds in the solid state, while that of Cr-Ni is a simple eutectic-type phase diagram at high temperatures and includes the low-temperature peritectoid reaction in the range near a CrNi(2) composition. Accordingly, the mixing behaviour in Al-Cr and Cr-Ni alloy melts was studied using the complex formation model in the weak interaction approximation and by postulating Al(8)Cr(5) and CrNi(2) chemical complexes, respectively, as energetically favoured.
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BACKGROUND/OBJECTIVES: Capacity development (CD) in food and nutrition is much more than formal training and includes human resource development, and organisational, institutional and legal framework development with the aim of enhancing nutrition-relevant knowledge and skills to support infrastructural development. The goal of the European Food Information Resource (EuroFIR) Network of Excellence has been to develop and integrate food composition data throughout Europe. EuroFIR joined forces in CD with the United Nations (UN) University and UN System Standing Committee on Nutrition, the Network for Capacity Development in Nutrition in Central and Eastern Europe, the Central and Eastern European Countries Food Data Systems network and with the Middle East and North African Capacity Building Initiative. The aim of this paper is to discuss an inventory of the status of food composition databases (FCDBs) and the training needs of compilers in non-EuroFIR countries in Central and Eastern Europe (CEE) and in the Middle East and North Africa (MENA), and to present the CD achieved through EuroFIR and other network collaborations. SUBJECTS/METHODS: Two online questionnaires were created addressing the FCDB status and specific training needs in countries of the targeted regions. Data were collected during 2006-2008 and then analysed. Subsequently, CD activities were organised. RESULTS: Contacts were established in 19 CEE and 7 MENA countries, of which several had national food composition tables, but no electronic versions. Education, training, workshops, networking and the sharing of experiences were uniformly requested. Subsequently, CD activities in EuroFIR were organised focussing on food composition courses, exchange visits, workshops and individual training for PhD students, junior scientists and other staff categories, as well as conferences linked to food composition research and food information. To facilitate CD activities, EuroFIR has signed a Memorandum of Understanding with the Czech Republic, Hungary, Slovenia, Croatia and Estonia. CONCLUSIONS: EuroFIR has created training activities that complement national activities. Collaboration with other networks has provided an overview of FCDB status and training needs, providing directions for CD activities in those countries. This provides a platform for new funding and further development and networking for CD, which would be conducive to European Commission objectives and public health strategies for CD.
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Sistemas de Gerenciamento de Base de Dados , Ciências da Nutrição , Inquéritos e Questionários , África do Norte , Escolaridade , Europa (Continente) , Alimentos , Humanos , Oriente Médio , Saúde Pública , Pesquisa , EnsinoRESUMO
Surface tension measurements are a central task in the study of surfaces and interfaces. For liquid metals, they are complicated by the high temperatures and the consequently high reactivity characterising these melts. In particular, oxidation of the liquid surface in combination with evaporation phenomena requires a stringent control of the experimental conditions, and an appropriate theoretical treatment. Recently, much progress has been made on both sides. In addition to improving the conventional sessile drop technique, new containerless methods have been developed for surface tension measurements. This paper reviews the experimental progress made in the last few years, and the theoretical framework required for modelling and understanding the relevant physico-chemical surface phenomena.
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Metais/química , Fenômenos Químicos , Modelos Químicos , Oxigênio/química , Tensão Superficial , Temperatura , TermodinâmicaRESUMO
BACKGROUND/OBJECTIVES: 'NutPlan' is developed within the EURRECA Network of Excellence (EURopean micronutrient RECommendations Aligned (http://www.eurreca.org). It is a user-friendly software programme with multiple functions: individual and group nutrition planning, recipe calculation, creating food labels, diet planning and nutrient intake assessment. This paper describes the newly developed software and its features. SUBJECTS/METHODS: 'NutPlan' contains the following databases: foods, dish recipes, meals, menus, average menus and glossary. These databases enable diet planning and diet analysis by comparing foods, dishes, meals or menus with currently available nutritional recommendations accessible by a link to EURRECA tool Nutri-RecQuest to meet individual/group nutritional needs.The software is upgraded by inserting new items (for example, foods, dishes, meals) and for a connection to other software programmes, thus allowing more advanced calculations to be completed. CONCLUSION: 'NutPlan' might be the software of choice for individual and group diet planning. It is aimed particularly at Eastern European and West Balkan countries, which currently lack dietary software. It is envisaged for use by small and medium enterprises in the food industry, as well as by health professionals, researchers and policy makers, and can be recommended for educational purposes. Given its characteristics of being upgraded to include new country-specific food data/database, it can be recognized as an important tool in nutritional capacity development in the Central Eastern European and other regions.
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Bases de Dados Factuais , Dieta/normas , Micronutrientes , Avaliação Nutricional , Software , Europa (Continente) , Humanos , Política Nutricional , Ciências da NutriçãoRESUMO
BACKGROUND: The EURRECA (EURopean micronutrient RECommendations Aligned) Network of Excellence collated current micronutrient recommendations. A user-friendly tool, Nutri-RecQuest, was developed to allow access to the collated data and to create a database source for use in other nutritional software tools. METHODS: Recommendations, that is, intakes of micronutrients sufficient to meet the requirements of the majority of healthy individuals of that population, from 37 European countries/organizations and eight key non-European countries/regions comprising 29 micronutrients were entered into a database. General information on the source of the recommendations, as well scientific background information, was added. RESULTS: A user-friendly web-based interface was developed to provide efficient search, comparison, display, print and export functions. CONCLUSION: Easy access to existing recommendations through the web-based tool may be valuable for bodies responsible for setting recommendations, as well as for users of recommendations including scientists, policy makers, health professionals and industry. Adding related dietary reference values such as average nutrient requirements and upper limits may extend the utility of the tool.
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Bases de Dados Factuais , Dieta/normas , Internet , Micronutrientes , Política Nutricional , Ferramenta de Busca , Europa (Continente) , HumanosRESUMO
The statistics for stroke in the USA reads like a familiar ad slogan cited in most papers pertaining to acute ischemic stroke (AIS). Stroke is the third leading cause of death in the USA. While stroke ranks third among all causes of death, behind diseases of the heart and cancer, it is the leading cause of serious long-term disability in the USA.(1) Approximately 795 000 people, 87% of whom are ischemic, suffer from stroke each year in the USA.(2) That means that on average, every 40 seconds someone within the USA develops a stroke. For 2009 the combined direct and indirect cost of stroke, from hospitalization and rehabilitation to institutionalization, is estimated at $68.9 billion within the USA.(2).
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Isquemia Encefálica/terapia , Revascularização Cerebral/métodos , Acidente Vascular Cerebral/terapia , Terapia Trombolítica/métodos , Doença Aguda , Isquemia Encefálica/diagnóstico , Revascularização Cerebral/tendências , Humanos , Acidente Vascular Cerebral/diagnóstico , Terapia Trombolítica/tendênciasRESUMO
Neck remodeling devices such as the Neuroform or Enterprise greatly facilitate the endovascular treatment of wide necked basilar apex aneurysms. The complex anatomy of the basilar apex affords opportunity for antegrade, multiple crossing and retrograde device placement strategies to facilitate coil embolization. A retrograde approach is possible in the presence of a posterior communicating artery large enough to allow device navigation. Our experience with a retrograde device placement strategy in three patients is reported. In two patients, device positioning extended from one P1 segment of the posterior cerebral artery to the other across the basilar apex. In one patient, device positioning extended from the P1 segment of the posterior cerebral artery across the basilar apex into the opposite superior cerebellar artery. All patients underwent reconstructive or deconstructive uncomplicated coil embolization after device placement with stable aneurysm occlusion on follow-up angiography. In appropriate anatomic situations, retrograde stent placement across the basilar apex through a posterior communicating artery may represent a preferred strategy for wide necked basilar apex aneurysms.
Assuntos
Oclusão com Balão/instrumentação , Oclusão com Balão/métodos , Aneurisma Intracraniano/terapia , Stents , Adulto , Angiografia Cerebral , Seguimentos , Humanos , Aneurisma Intracraniano/diagnóstico por imagem , Aneurisma Intracraniano/patologia , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Procedimentos Neurocirúrgicos/instrumentação , Procedimentos Neurocirúrgicos/métodos , Estudos Retrospectivos , Resultado do TratamentoRESUMO
This paper, which is based on another recent work, (Mezzasalma, S. A., Phys. Rev. E 55 (4), (1997)) deals with experiments and theory concerning an aqueous dispersed system formed from silicon nitride (Si3 N4 ), alumina (Al2 O3 ), and mixed silicon nitride + alumina (Si3 N4 + Al2 O3 ) solid agglomerates. From titration data applied to a thermodynamic equilibrium condition, the minimum number of each agglomerate species and their maximal average dimensions have been derived as functions of the aqueous solution pH. These parameters are of the order of, respectively, (1-2) &mgr;m for Si3 N4 and Al2 O3 agglomerates and (20-50) &mgr;m for the mixed agglomerates. The numbers of solid particles of all species are poorly correlated with changes in pH of the liquid phase. This behavior has been interpreted as intrinsically related to the complexity of the system which, due to the many interactions among the different species, probably becomes nondeterministic. In order to describe such behavior a probabilistic approach has been developed. The probability of finding a given solid agglomerate number within a scatter band varies with the suspension pH. Furthermore, the scatter band amplitude becomes negligible near the isoelectric point. Accordingly, only the numbers of aggregates derived in the neighborhood of the isoelectric point are predictable.
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Serum levels of gastrin, somatostatin and vasoactive intestinal polypeptide were evaluated in 105 noninsulin dependent diabetics (25 of them had a pyloric dysfunction). The serum levels were determined by RIA and blood was taken before and after the test meal. The basal gastrin level was significantly higher in patients with the pyloric dysfunction (p < 0.001). 45 minutes later the serum levels of vasoactive intestinal polypeptide and somatostatin were significantly higher in diabetics with the pyloric dysfunction (p < 0.001). The serum levels of gastrin, somatostatin and vasoactive intestinal polypeptide were impaired in diabetics with the pyloric dysfunction and might be associated with its pathogenesis.
Assuntos
Diabetes Mellitus Tipo 2/fisiopatologia , Gastrinas/sangue , Motilidade Gastrointestinal , Somatostatina/sangue , Peptídeo Intestinal Vasoativo/sangue , Diabetes Mellitus Tipo 2/sangue , Ingestão de Alimentos , Feminino , Esvaziamento Gástrico , Humanos , Masculino , Pessoa de Meia-Idade , Piloro/fisiopatologiaRESUMO
Parasympathetic function and plasma hPP response to a protein rich meal were evaluated in 105 insulin non-dependent diabetic patients: 20 with autonomic neuropathy (group A), diagnosed by Clonidin test; 35 patients with neurophysiological evidence of polyneuropath (group B); 30 patients with autonomic neuropathy and polineuropathy (group C), and 20 patients without any sign of neuropathy (group D). Plasma hPP levels were determined by RIA using an anti-hPP antiserum, kindly provided by Prof. S. R. Bloom (Hammersmith Hospital, London). Blood was taken at 0. 45 and 60 minutes after the beginning of the meal. In groups A and C, the meal induced hPP increase was significantly lower than in group D (p 0.001). All group B patients had a marked increase in the peptide, similar to that in diabetics without neuropathy. These result ssuggest that diabetic autonomic neuropathy is associated with dysfunction of hPP secretion, and that the evaluation of hPP response to test meal may be a sensitive and simple method for the assessment of paraympathetic impairment in diabetes.
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Doenças do Sistema Nervoso Autônomo/sangue , Diabetes Mellitus Tipo 2/sangue , Neuropatias Diabéticas/sangue , Proteínas Alimentares/administração & dosagem , Polipeptídeo Pancreático/sangue , Feminino , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
The aim of our work was to study specific aspects of statistical Weinstein-Bayes's analysis in order to find the most suitable program for presenting our results and for obtaining information which could be used as a guide in the clinical decision-making process. Our efforts resulted in a computer processing system based on modified Weinstein-Bayes receiver operating characteristics (ROC) analysis. The data analysis provides numeric values of sensitivity, specificity, positive predictive value and negative predictive values as output tumour marker databases, which would serve as graphic input. It becomes possible to plot the ROC curve as a graphical distribution of tumour marker levels. The computer program also allows the estimation of the potential utility of the serum tumour marker measured in patients with various diseases, simultaneous determination of serum tumour markers in diseased patients, and the real value of each serum tumour marker level in diseased patients.
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Biomarcadores Tumorais/sangue , Sistemas Inteligentes , Neoplasias/sangue , Adenocarcinoma/sangue , Antígenos Glicosídicos Associados a Tumores/sangue , Teorema de Bayes , Antígeno Carcinoembrionário/sangue , Neoplasias do Colo/sangue , Gráficos por Computador , Tomada de Decisões , Previsões , Humanos , Neoplasias/diagnóstico , Valor Preditivo dos Testes , Prevalência , Curva ROC , Neoplasias Retais/sangue , Sensibilidade e Especificidade , SoftwareRESUMO
Basal and postprandial levels of gastrin, somatostatin, vasoactive intestinal polypeptide (VIP) and pancreatic polypeptide (PP) were followed up in 105 patients with non insulin dependent diabetes mellitus (20 with autonomic neuropathy only, 35 with peripheric neuropathy only, 30 with autonomic and peripheric neuropathy simultaneously and 20 without any sign of neuropathy) and in the control group of 40 individuals. Serum levels of gastrin, somatostatin, VIP and PP are determined by a RIA (used kits of Prof. SR Bloom, Hammersmith Hospital, London). The results of investigation showed significantly higher basal and postprandial levels of gastrin and VIP in patients with autonomic neuropathy in comparison with the group without neuropathy and with the control group (p < 0.001). The serum levels of somatostatin did not differ significantly between the groups of diabetics with and without neuropathy. Basal level of PP was significantly lower and postprandial PP levels remained low in patients with autonomic neuropathy in comparison with the group without neuropathy (p < 0.001). We postulate that basal and postprandial gastrin and VIP levels raised secondary to partial vagotomy in diabetics with autonomic neuropathy. Measuring PP serum levels in diabetics after a protein rich meal can be useful to check vagus nerve function in the gastrointestinal tract in order to detect autonomic neuropathy.
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Doenças do Sistema Nervoso Autônomo/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Neuropatias Diabéticas/metabolismo , Hormônios Gastrointestinais/sangue , Adulto , Feminino , Gastrinas/sangue , Humanos , Masculino , Pessoa de Meia-Idade , Polipeptídeo Pancreático/sangue , Somatostatina/sangue , Peptídeo Intestinal Vasoativo/sangueRESUMO
In purpose of early diagnosis of gallbladder carcinoma, the serum levels of tumor markers CA 72-4, CA 19-9, CEA, AFP, Ferritin and beta HCG were determined in 124 patients with benign and malign diseases of gallbladder, before and 10 days after the operation. The most important clinical significance have CA 72-4 and CA 19-9, which are increased in Ca in situ and carcinoma of the first stage. These early stages of carcinoma cannot be diagnostified by preoperative echotomography, but radical operation is possible with recover by all means. These two tumor markers should be attended in risk group of patients for rising gallbladder carcinoma: calculosis and polyposis. The rest of tumor markers are increased in progressive carcinoma with infiltration of surrounding tissue and metastases.