43,994 research outputs found
Progressive deterioration of beta-cell function in non-obese type 2 diabetic subjects. Post-prandial level of plasma C-peptide is an indication of insulin dependency.
No full textThe purpose of the present study was to characterize secondary failure (SF) to oral hypoglycaemic agents by assessment of threshold insulin-secretion values in relation to diabetes duration. One hundred and forty-seven nonobese diabetic patients, 35 to 80 years of age, with disease duration ranging from 1 to 36 years, were studied. Beta-cell function was assessed by meal-stimulated (ΔCP) and glucagon-stimulated (ΔaCP) C-peptide concentrations. The quality of glycaemic control was considered good if mean daily blood glucose was less than 8.5 mmol/l. One group with good (NOb-GC) and another with poor control (NOb-SF) were established. Mean daily glycaemia was negatively correlated with ΔCP or ΔaCP (r = -0.703 vs r = -0.696; p <0.001) more than with basal C-peptide (r = -0.453; p<0.001). A close positive correlation between meal-stimulated (ΔCP) and glucagon-stimulated (ΔaCP) C-peptide concentrations was observed {r = 0.869; p<0.001). Residual beta-cell function (ΔCP and ΔaCP) was significantly correlated with known disease duration in both groups (GC : r = -0.693 and SF: r = -0.680 ; p < 0.001). Nonobese patients with SF showed early impaired secretion during the first years of disease, meal-stimulated ΔCP being below 0.350 mmol/l. The most useful result in this study was the incremental value of C-peptide (ΔCP), which showed minimal overlapping between the two groups. Basal, postprandial or postglucagon absolute values were less discriminating. The daily profile allowed measurement of both glycaemic control and insulin production after a regular meal. The validity of this measurement was confirmed by the strong correlation between meal-stimulated and glucagon-stimulated ΔC-peptide concentrations. This parameter is a useful physiological marker of secondary failure
Is type 2 diabetes mellitus a different disease in non-obese and obese patients?
No full textThe main purpose of this work was to study the possible differences in insulin secretion in a large group of type 2 diabetic patients in relation to diabetes duration, obesity, and the presence of secondary failure after treatment with oral hypoglycemic agents. RESEARCH DESIGN AND METHODS - There were 147 nonobese and 215 obese type 2 diabetic subjects, aged 35-80 years, investigated in a cross-sectional descriptive study. Subjects were grouped according to whether glycemic control was good (mean blood glucose <8.5 mmol/l) or poor. β-Cell function was assessed by measuring meal-stimulated insulin and C-peptide concentrations, as the mean of the three postprandial increments above the premeal value. RESULTS - Basal C-peptide concentrations were significantly higher in obese than nonobese patients of both groups. The mean of meal-stimulated C-peptide concentrations was also significantly higher in obese than nonobese patients with good glycemic control, but not in the secondary failure groups. In nonobese and obese patients considered separately, a significant negative correlation between the mean of daily blood glucose and meal-stimulated C-peptide was observed (r = -0.705 and r= -0.679, respectively, P < 0.001) and the residual β-cell function was significantly correlated with the known duration of diabetes and metabolic control, but not with BMI, in both groups. CONCLUSIONS - On average, obese diabetic subjects showed higher meal-stimulated C- peptide than nonobese subjects only in well-controlled groups. In both obese and nonobese patients, an inverse association between meal-stimulated insulin secretion and duration of diabetes was observed. In obese patients, as in nonobese patients, the lower β-cell function seems likely to be the major pathogenetic factor in the appearance of secondary failure, while being overweight plays only a minor role, thus showing that type 2 diabetes is the same disease in obese and nonobese patients
The L-p-to-L-q boundedness of commutators with applications to the Jacobian operator
No full textSupplying the missing necessary conditions, we complete the characterisation of the L-p -> L-q boundedness of commutators [b, T] of pointwise multiplication and Calderon-Zygmund operators, for arbitrary pairs of 1 q, our results are new even for special classical operators with smooth kernels. As an application, we show that every f is an element of L-p(R-d) can be represented as a convergent series of normalised Jacobians J(u) = det del uof u is an element of (over dot(W))(1,dp)(R-d)(d). This extends, from p = 1 to p > 1, a result of Coifman, Lions, Meyer and Semmes about J:. (over dot(W))(1,d)(R-d)(d) -> H-1(R-d), and supports a conjecture of Iwaniec about the solvability of the equation Ju = f is an element of L-p(R-d). (C) 2021 The Author(s). Published by Elsevier Masson SAS.Peer reviewe
Gastrokinetic effects of levosulpiride in dyspeptic patients with diabetic gastroparesis.
No full textDe Maiestate / Praeside M. Jacobo Thomasio, Moralis Philosoph. P. P., publice disputabit Johannes Dunte, R. L. Author & Respon: ad diem 9. Septembr. H L. Q. C.
No full textDE MAIESTATE / PRAESIDE M. JACOBO THOMASIO, MORALIS PHILOSOPH. P. P., PUBLICE DISPUTABIT JOHANNES DUNTE, R. L. AUTHOR & RESPON: AD DIEM 9. SEPTEMBR. H L. Q. C.
De Maiestate / Praeside M. Jacobo Thomasio, Moralis Philosoph. P. P., publice disputabit Johannes Dunte, R. L. Author & Respon: ad diem 9. Septembr. H L. Q. C. (1)
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Going Beyond Counting First Authors in Author Co-citation Analysis
No full textThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Recommendations for the use of cardiovascular tests in diagnosing diabetic autonomic neuropathy
No full textDespite its prevalence, clinical and prognostic impact, diabetic autonomic neurop- athy, is widely under-diagnosed. The need for training and expertise to perform the cardiovas- cular tests (usually the task of diabetologists) is one possible reason. The availability of computer-assisted systems has allowed a wider diffusion of testing, but has also highlighted the need for an adequate knowledge of physiopathological backgrounds for their correct appli- cation and interpretation. The recommendations presented here were developed by the Neuropathy Study Group of the Italian Society of Diabetology and then endorsed by the Italian Association for the Study of Neurovegetative System, to promote the widespread adoption of good clinical practice in diabetic cardiovascular autonomic testing by outlining main evidence- based aspects, i.e. which tests, how to perform them, adequate interpretation of the results and their diagnostic use, confounding conditions that can impact on tests reliability. There- fore, these recommendations include the essential aspects of the physiopathological substrate of the tests, the controversial points in their analysis, their diagnostic characteristics, as well as safety. Detailed information is given on the physiological (age, weight, body position, resting heart rate and blood pressure, respiratory pattern, exercise, meals, acute blood glucose changes) and pathophysiological confounding factors, with emphasis on the effects of drugs. Instructions on how to perform the tests and interpret their results are also consid- ered together with indications of candidate patients and periodicity of testing. A patient instruction sheet on why and how to perform the tests is included. Finally, the specific require- ments for computerized systems to perform and evaluate cardiovascular tests are provided
Appropriate Similarity Measures for Author Cocitation Analysis
No full textWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
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Raul Morin, author of 'Among the Valiant' shakes hands with Dr. Hector P. Garcia (photograph)
No full text(L. to R.): Raul Morin, author of 'Among the Valiant' shakes hands with Dr. Hector P. Garcia
Dispelling the Myths Behind First-author Citation Counts
No full textWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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