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Query: UMLS:C0011849 (diabetes)
 277,896 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Although the new nonionic contrast agents are safer than ionic agents, renal insufficiency and even death still occur occasionally. Therefore, we have explored the use of carbon dioxide (CO2) as an alternative angiographic contrast agent used in combination with digital subtraction angiography. Clinical observations have been made in over 800 patients. The images obtained are of equivalent diagnostic quality compared with those using conventional iodinated contrast agents. Recent advances in imaging, including "stacking," provide images comparable with iodinated contrast. Very small vessels, equivalent to third-order branches of the renal artery, can be imaged satisfactorily with CO2. Occasional studies with CO2 yield information not apparent with iodinated contrast agents, including excellent visualization of arteriovenous shunts, collateral circulations, malignant tumors, and minute amounts of arterial bleeding. Many of the advantages and disadvantages of CO2 derive from its special physical and chemical properties. The advantages include no allergic potentiation and no renal metabolism of CO2, because CO2 is cleared by the lungs and does not recirculate. Other advantages include delivery by very small catheters because of the low viscosity of CO2, minimal discomfort on injection, and very low cost. However, the low-density and compressibility of CO2 poses some special problems. Imaging requires digital subtraction angiography with electronic enhancement and injections require an experienced investigator and, ideally, a dedicated CO2 injector. The dedicated CO2 injector provides calculated, controlled dosing and rates for injection, while excluding the possibility of air contamination. The buoyancy of CO2 inhibits good filling of dependent vessels. Accordingly, CO2 does not normally produce good nephrographic images, although proximal renal arteries are normally shown clearly. Experimental studies in dogs, whose renal arteries have been injected repeatedly with very large doses of CO2, demonstrate only transient changes in renal blood flow and no endothelial cell damage. However, these studies also showed clearly that renal ischemia can occur due to a "vapor lock" phenomenon if the kidney is positioned vertically above the injection site, and recurrent injections are given without time for absorption of the arterially delivered CO2 boluses. Uncontrolled studies in over 800 patients have confirmed that CO2 likely has a very low renal toxicity. At the University of Florida, CO2 is the radiologic contrast agent of choice in patients with renal insufficiency, especially those with diabetes mellitus, and in those with pre-existing allergy to iodinated contrast agents. Further controlled clinical studies are required to define the true clinical utility and safety of CO2 compared with conventional radiologic contrast agents.
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PMID:CO2 digital angiography: a safer contrast agent for renal vascular imaging? 794 29

This study examined the effect of the aldose reductase inhibitor (ARI), ponalrestat, on decreased motor nerve conduction velocity (MNCV) and increased resistance to hypoxic conduction block (RHCB) in diabetic rats. The effects of 5 mmol/L, and 25 mmol/L glucose on RHCB were also determined. Twenty streptozotocin-diabetic rats formed two groups; untreated and ponalrestat-treated (300 mg/kg diet/day); 10 non-diabetic rats acted as controls. MNCV was measured in vivo after 4 weeks of diabetes +/- treatment in the sciatic/tibialis system and rats were killed 48-72 h later. The median nerves were removed and assayed for polyol pathway metabolites by gas chromatography. The sciatic nerves were dissected to form endoneurial preparations for the recording of compound action potentials (CAPs) in vitro and maintained in media with either 5 (standard) or 25 (high) mmol/L glucose and initially gassed with 95% O2/5% CO2. Oxygen content was then reduced to 8% for 40 min to study the effect of this period of hypoxia on CAP amplitude. MNCV (m/s +/- SD) in diabetic rats (43.86 +/- 4.86) was decreased compared to controls (52.24 +/- 6.59) and this decrease was absent in the ARI-treated group (52.24 +/- 6.90). The decline in CAP amplitude during a 40-min hypoxic period was greater in controls than in diabetics. Ponalrestat treatment caused a decline which was mid-way between these two in standard medium and closer to that seen in control preparations in high glucose medium. These findings give further support to the involvement of the sorbitol pathway in the development of the acute MNCV deficit in diabetic rats and indicate that it may have a partial role in the development of increased resistance to hypoxic conduction block in peripheral nerves.
J Diabetes Complications
PMID:Increased resistance to hypoxic conduction block in sciatic nerves of diabetic rats: effects of extracellular glucose concentration and of aldose reductase inhibition. 816 85

Daily variations of the aspiration CO2 carbon isotope content (CIC) were studied at three metabolic states: norm, insulin-dependent diabetes (IDD), and obesity. The groups of subjects were studied in a clinic during 24 hours. Analysis of the delta 13C daily curves of the exhaled air CO2 allowed us to find the link between variations of CIC with daily rhythms in the organism and with metabolic shifts at IDD and obesity. At metabolic norm it is possible two phases on the daily curve, corresponding to daytime and nighttime metabolism types with hormonally regulated transition between them. The daytime phase of the curve consists of altering maxima and minima, linked to periodicity in feeding and movement activity. The nighttime phase is characterized by continuous enrichment of CO2 by 12C. At IDD in insulin therapy conditions the most prominent difference from norm and obesity is the stable CIC at nighttime. At daytime during weakening of the exogenous insulin action there appear horizontal regions on the delta 13C CO2 curves, similar to the nighttime behaviour. At obesity the daily curves are close to the normal ones, but they are more smooth and impoverished in 13C. No clear transition between the daytime and nighttime metabolism types can be observed. At obesity and IDD the character of the daily curves can be observed.
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PMID:[Daily changes in the carbon isotope composition of CO2 in expired air of persons with various metabolic disorders]. 819 5

The treatment of the diabetic foot is a common and sometimes difficult problem. The treatment of the characteristic lesions of the diabetic foot involves many forms of therapy: these include contact dressings and topical treatments. The different therapies that have been applied do not often give satisfactory results. Therefore, for this purpose, we have studied the effect of biostimulation of wound-healing by utilising the CO2 laser together with the action of the KTP laser on 25 patients (11 females and 14 males), all suffering from diabetes mellitus with polyneuropathic ulcers of the foot. Low out-put laser irradiation may stimulate granulation tissue and collagen production in fibroblasts. Many studies observed a regeneration of microcirculation in the ulcer and a regeneration of lymphatic circulation. The laser irradiation method produces a sterilizing effect from bacteria that over-infect the diabetic ulcer too. Each patient underwent a surgical treatment of the edges of the ulcers with CO2 and KTP laser (wavelength 532 nm) focused, and a combined phototherapy (CO2 laser and afterwards KTP laser, defocused). The irradiation was carried out through laser beam (by optic fiber for KTP) manually directed, until all of the ulcer surface became irradiated. On the skin around the ulcer, an omental derived cream (fractionated porcine omental lipid extracts) was daily applied, independently from the laser treatment, to evaluate the angiogenic effect of this substance.(ABSTRACT TRUNCATED AT 250 WORDS)
Diabetes Res Clin Pract 1993 Jul
PMID:The diabetic foot. General considerations and proposal of a new therapeutic and preventive approach. 825 21

We have shown previously that prolonged exposure to insulin and glucose impairs the insulin-responsive glucose transport system in primary cultured adipocytes. To assess the ability of insulin and glucose to regulate other cellular insulin actions, epididymal rat adipocytes were cultured in media containing 0-15 mM D-glucose and with or without insulin (50 ng/ml). After 24 h, cells were washed and basal and maximally insulin-stimulated rates of 2-deoxy-D-glucose uptake, L-leucine incorporation into protein, glucose oxidation to CO2, glucose incorporation into lipids, and glycogen synthase activity were measured. The results confirmed that glucose potentiates insulin's chronic ability to decrease basal and maximal glucose transport rates by approximately 50% at 5 mM glucose and by approximately 70% at 15 mM glucose compared with control cells. However, neither glucose nor insulin, alone or in combination, affected rates of leucine incorporation into protein. In addition, basal and maximal rates of glucose oxidation and of glucose incorporation into lipids were not regulated by glucose, and maximal responses declined approximately 50% over 24 h only when insulin was not present during preincubation (i.e., chronic insulin exposure was necessary to maintain full maximal responses). Glycogen synthase activity was measured in a cell-free system (0.5 mM UDP-glucose, with 10 or 0.01 mM glucose-6-phosphate) after exposing intact cells to glucose and insulin. Both short-term (1 h) and long-term (24 h) exposure to glucose alone led a dose-dependent increase in I-form and D-form glycogen synthase activity. Chronic exposure to insulin also increased total glycogen synthase activity (I- plus D-form) but did not affect absolute rates of maximally stimulated I-form activity. Glucose (but not insulin) increased the cellular content of immunoreactive glycogen synthase by 70% after 1 h. These results show that 1) chronic exposure to glucose and insulin impairs insulin responsiveness of the glucose transport system but does not affect rates of amino acid incorporation into protein; 2) the chronic presence of insulin is necessary for the maintenance of normal maximally stimulated rates of glucose oxidation and of glucose incorporation into lipids in cultured cells; and 3) glucose increases both D-form and I-form glycogen synthase activity, in part by increasing the amount of synthase protein, whereas chronic insulin exposure increases total glycogen synthase activity without altering maximal absolute rates of I-form activity.(ABSTRACT TRUNCATED AT 400 WORDS)
Diabetes 1994 Jan
PMID:Biological actions of insulin are differentially regulated by glucose and insulin in primary cultured adipocytes. Chronic ability to increase glycogen synthase activity. 826 17

When in some selected patients, a direct arterial surgery (DAS) procedure or an endoluminal surgery (ES) are required for a chronic arterial ischemia (III or IV degrees), and an arteriography with contrast is absolutely contraindicated (because of severe renal failure without hemodialysis program or a severe congestive heart failure or a hyperthyroidism or a seriously demonstrated hypersensibility against the contrast agents); an angiography by digital subtraction with carbon dioxide (DIVAS-CO2) is indicated. This technique provides good quality images with minimal risks for the patient and an adequate study for ulterior treatment. We report a case of a 67-years-old woman, with diabetes-II, ischemic cardiopathy, arterial hypertension and a demonstrated hypersensibility against the iodide compounds. The patient was admitted because of a chronic ischemia (IV degree) with ischemic ulcerations on some fingers from the left foot. High doses of analgesic drugs were needed. Because the hypersensibility against the iodide compounds, an angiography with CO2 was carried out. The good quality images provided by this technique showed the factibility of a revascularization.
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PMID:[Digital subtraction angiography with carbon dioxide in severe arterial ischemia and allergy to iodinated compounds]. 839 9

The ventilatory response to hyperoxic progressive hypercapnia was examined by comparing 3 test groups: 7 diabetic patients with AN, 8 diabetic patients without AN, and 8 normal control subjects. In each group, a significant linear correlation was found between PaCO2 and VE. The slopes of the regression curves relating PaCO2 to VE were significantly steeper in the healthy control subjects and diabetic patients without AN than in those with AN (P < 0.01). We conclude that the ventilatory response to progressive hypercapnia is reduced in diabetic patients with AN. By analyzing the power spectrum and the amplitude behavior of the diaphragmatic EMG (calculated from the fc and RMS, respectively), we could exclude a disturbance of neural descending pathways and respiratory muscle dysfunction as possible causal mechanisms for the impaired ventilatory response to increasing CO2. By using lung function analysis, causal factors such as alterations in respiratory system mechanics also could be excluded. As diabetes is known to affect the endogenous opioid system, which, in turn, affects the ventilatory response to CO2, naloxone, as a specific opioid antagonist, was administered in all 3 test groups. Naloxone produced a significant increase of ventilatory response to hypercapnia in the healthy control subjects (P < 0.01), but produced no effect in either of the diabetic groups.(ABSTRACT TRUNCATED AT 250 WORDS)
Diabetes 1993 Feb
PMID:No effect of naloxone on ventilatory response to progressive hypercapnia in IDDM patients. 842 64

The effect of diabetes mellitus on the cerebrovascular response to CO2 is unclear. We examined the effects of diabetes on cerebral blood flow (CBF) and cerebral oxygen uptake (CMRO2) during CO2 alterations. Four groups of dogs were studied: nondiabetic, normoglycemic controls; non-diabetic acute hyperglycemia; diabetic (pancreatectomy) with high-dose insulin treatment to maintain blood glucose between 4.0 and 6.0 mM; and diabetic with low-dose insulin treatment to maintain blood glucose at 13.2 +/- 0.4 mM. Six weeks after either sham surgery or pancreatectomy, dogs were anesthetized with fentanyl (50 micrograms/kg) plus pentobarbital (10 mg/kg), and microsphere determinations of CBF were made during normo-, hypo-, and hypercapnia. On the day of the study, arterial glucose levels in the control, acute hyperglycemia, and high- and low-dose insulin diabetic groups were 4.0 +/- 0.3, 14.9 +/- 2.5, 3.3 +/- 0.8, and 13.3 +/- 0.7 mM, respectively, at control. The corresponding baseline CMRO2 levels were 2.8 +/- 0.2, 3.0 +/- 0.2, 4.1 +/- 0.4, and 4.0 +/- 0.3 ml O2.100 g-1 x min,1, and the values in both diabetic groups were higher than control. Normocapnic CBF in the acute hyperglycemia, high-dose insulin, and low-dose insulin groups was elevated from control (54 +/- 3, 50 +/- 3, 51 +/- 3 vs. 36 +/- 1 ml x 100 g-1 x min-1) and cerebrovascular resistance was lower (2.24 +/- 0.15, 2.51 +/- 0.14, 2.38 +/- 0.21 vs. 3.35 +/- 0.18 mmHg.ml-1 x 100 g.min). CBF responses to both hypercapnia and hypocapnia were similar among groups. Thus both acute hyperglycemia and diabetes decrease cerebrovascular resistance and increase CBF.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Cerebral blood flow responsivity to CO2 in anesthetized chronically diabetic dogs. 847 84

Prospective registry of newly diagnosed cases of insulin-dependent diabetes mellitus in subjects under 20 years began in 1988 in Aquitaine, Lorraine, Basse- and Haute-Normandie (population base = 2,288,018 inhabitants under 20). The registry gave a complete coverage of the population as the capture-recapture method gave a 98% yield. The mean annual incidence was 7.6/100,000 for the period 1988-1990. A specific survey aimed at describing clinical and biological presentation at diagnosis. The main symptom was polyuria in 98% of the cases, fatigue in 58% and weight loss in 44%. Abdominal pain was reported in 34% of the cases. Diagnosis was ascertained by measurement of plasma glucose, which was > or = 11 mmol/l in 95% of the cases and associated with ketonuria in 84% of the children. Coma in 13% of the children and acidosis (total CO2 < or = 18 mmol/l) in 48% showed the severity at diagnosis. Ketonuria and acidosis were significantly more frequent in the younger age group (0-4 yr). Diagnosis was made by a general practitioner in the majority of the cases; conversely insulinotherapy was initiated at the hospital in 95% of the cases. Initial insulin treatment was 2 daily injections. Following the French experience the collaborative network EURODIAB ACE has undertaken the same survey among the European Registries. Important geographical variations in incidence rates of IDDM in children has been reported across Europe but it is not known whether this interferes with presentation at diagnosis of the disease.
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PMID:[Diagnosis of insulin-dependent diabetes in children: data from the incidence registry]. 893 70

In symptomatic endstage coronary artery disease after full medical therapy (antianginal drugs, betablockers and ACE-inhibitors) further therapeutical options both for the interventional cardiologist with little hope for improvement by PTCA, stent, rotablation and atherectomy and for the cardiac surgeon with bypass surgery and endarterectomy are not available by definition due to the diffuse arteriosclerotic vessel morphology. In those patients one can therefore consider transmyocardial laser therapy (TMR) as the ultimate treatment option. It then is primarily a palliative measure to reduce the patient's symptoms. Improving perfusion and prognosis remains the most important goals, however. TMR can be utilized as the only revascularizing treatment measure or in combination with CABG or PTCA. According to data from international registries, few controlled and several non controlled studies and our own registry in Marburg with now 101 patients improvement of angina and/or dyspnoea can be expected in more than 60% of patients with end stage coronary artery disease (CAD). The patient cohort comprises symptomatic individuals after CABG or multiple PTCAs or with diffuse CAD in diabetes mellitus or with most severe hypercholesterinemia. We consider these above mentioned criteria as the only validated criteria to enter patients with endstage CAD in our controlled study. Hypothetical options for treatment by TMR such as vasculopathies after heart transplantation, cardiomyopathies under the notion of a possible but not proven microangiopathy are not accepted in our institution at present. Before TMR all patients are assessed for their angina class according to the Canadian Cardiac Society (CCS I-IV)) and their exercise capacity according to the New York Heart Association classification (NYHA I-IV) and reassessed regularly after 3, 6 and 12 months. Thallium/Te MIBI scans at rest- and whenever possible at exercise as well as stress echocardiography are carried in the patients to assess symptomatic improvement, alterations in myocardial perfusion and functional efficacy by TMR. By intermediate analysis the 101 patients of our registry more than 60% of the patients had improved their angina class by at least one classe, some patients have improved perfusion as assessed by scintigraphy, which makes at present a trend but not yet a significant difference, whereas central hemodynamics and ejection fraction remained virtually unchanged in most patients reassessed after TMR. In our analysis mortality of the 101 TMR patients was assessed and plotted on Kaplan Meier survival curves. Mortality at 6 months was 11%. When compared to a historical group of patients with identical CCS and comparable NYHA classes, who were worked up in the manner of a case control study, the TMR mortality was marginally but not yet significantly lower than one would expect from these control patients with terminal CAD treated purely by medication: Their 6 months mortality was 14%. Remarkably but not unexpectedly patients with comparable CCS classes, who could still be treated by PTCA and/or CABG had a significantly lower 6 months mortality than TMR patients or patients on antianginal drugs only. The pathophysiological mechanisms for the symptomatic improvement by laser therapy are not yet fully understood. The 1 mm transmyocardial channels created by the CO2 laser have been postulated to permit perfusion from the ventricular cavity and to seek connection to capillaries and vessels present in the malperfused myocardium thus improving the perfusion by newly created connections and sinusoids from the ventricular cavity. Although there is clear evidence for the presence of open channels acutely and within a few days after TMR therapy little evidence in man is as yet available on the question whether the channels remain open in the long run and, if so, whether they can actually improve perfusion to a substantial degree...
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PMID:[Indications for transmyocardial laser therapy]. 906 76


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