Paludiculture can support biodiversity conservation in rewetted fen peatlands.

Paludiculture, the productive use of wet or rewetted peatlands, offers an option for continued land use by farmers after rewetting formerly drained peatlands, while reducing the greenhouse gas emissions from peat soils. Biodiversity conservation may benefit, but research on how biodiversity responds to paludiculture is scarce. We conducted a multi-taxon study investigating vegetation, breeding bird and arthropod diversity at six rewetted fen sites dominated by Carex or Typha species. Sites were either unharvested, low- or high-intensity managed, and were located in Mecklenburg-Vorpommern in northeastern Germany. Biodiversity was estimated across the range of Hill numbers using the iNEXT package, and species were checked for Red List status. Here we show that paludiculture sites can provide biodiversity value even while not reflecting historic fen conditions; managed sites had high plant diversity, as well as Red Listed arthropods and breeding birds. Our study demonstrates that paludiculture has the potential to provide valuable habitat for species even while productive management of the land continues.

An SEM compatible plasma cell for in situ studies of hydrogen-material interaction.

An in situ hydrogen (H) plasma charging and in situ observation method was developed to continuously charge materials, while tensile testing them inside a scanning electron microscope (SEM). The present work will introduce and validate the setup and showcase an application allowing high-resolution observation of H-material interactions in a Ni-based alloy, Alloy 718. The effect of charging time and pre-straining was investigated. Fracture surface observation showed the expected ductile microvoid coalescence behavior in the uncharged samples, while the charged ones displayed brittle intergranular and quasi-cleavage failure. With the in situ images, it was possible to monitor the sample deformation and correlate the different crack propagation rates with the load-elongation curves. H-charging reduced the material ductility, while increasing pre-strain decreased hydrogen embrittlement susceptibility due to the possible suppression of mechanical twinning during the tensile test and, therefore, a reduction in H concentration at grain and twin boundaries. All the presented results demonstrated the validity of the method and the possibility of in situ continuously charging of materials with H without presenting any technical risk for the SEM.

Bare, bio-active and hydrogel-coated coils for endovascular treatment of experimentally induced aneurysms. Long-term histological and scanning electron microscopy results.

Endovascular treatments of cerebral aneurysms with bare platinum coils have a higher rate of recurrence compared to surgical clipping. This may be related to failed vessel wall reconstruction since histological and scanning electron microscopy results following embolization failed to demonstrate neoendothelialization over the aneurysm neck. The present study tried to elucidate whether the use of modified coils resulted in a better rate of reconstructing the vessel wall over the aneurysm neck in experimental aneurysms. Aneurysms were created in 20 rabbits by intraluminal elastase incubation of the common carotid artery. Five animals each were assigned to the following groups: untreated, bare platinum coils, bioactive coils with polyglycolic/polylactic acid coating, and hydrogel-coated platinum coils. After 12 months, angiography, histology and scanning electron microscopy was performed. No neoendothelial layer was visualized in the bioactive and bare coil groups with a tendency to an increased layering of fibroblasts along the bioactive coils at the aneurysm fundus. However, at the aneurysm neck perfused clefts were present and although a thin fibrinous layer was present over some coils, no bridging neointimal or neoendothial layer was noted over different coils. Following loose Hydrogel coiling, a complete obliteration of the aneurysm was present with neoendothelialization present over different coil loops. The study demonstrates that with surface coil modifications complete and stable aneurysm obliteration may become possible. A smooth and dense surface over the aneurysm neck may be necessary for endothelial cells to bridge the aneurysm neck and to lead to vessel wall reconstruction.

Magnetic versus manual guidewire manipulation in neuroradiology: in vitro results.

INTRODUCTION: Standard microguidewires used in interventional neuroradiology have a predefined shape of the tip that cannot be changed while the guidewire is in the vessel. We evaluated a novel magnetic navigation system (MNS) that generates a magnetic field to control the deflection of a microguidewire that can be used to reshape the guidewire tip in vivo without removing the wire from the body, thereby potentially facilitating navigation along tortuous paths or multiple acute curves. METHOD: The MNS consists of two permanent magnets positioned on either side of the fluoroscopy table that create a constant precisely controlled magnetic field in the defined region of interest. This field enables omnidirectional rotation of a 0.014-inch magnetic microguidewire (MG). Speed of navigation, accuracy in a tortuous vessel anatomy and the potential for navigating into in vitro aneurysms were tested by four investigators with differing experience in neurointervention and compared to navigation with a standard, manually controlled microguidewire (SG). RESULTS: Navigation using MG was faster (P=0.0056) and more accurate (0.2 mistakes per trial vs. 2.6 mistakes per trial) only in less-experienced investigators. There were no statistically significant differences between the MG and the SG in the hands of experienced investigators. One aneurysm with an acute angulation from the carrier vessel could be navigated only with the MG while the SG failed, even after multiple reshaping manoeuvres. CONCLUSION: Our findings suggest that magnetic navigation seems to be easier, more accurate and faster in the hands of less-experienced investigators. We consider that the features of the MNS may improve the efficacy and safety of challenging neurointerventional procedures.

Efficacy of an EMG-biofeedback therapy in fibromyalgia patients. A comparative study of patients with and without abnormality in (MMPI) psychological scales.

OBJECTIVE: The aim of the present study was to investigate the efficacy of EMG-biofeedback in female fibromyalgia patients with and without abnormality in the MMPI. METHODS: According to their MMPI profile out of a total of 24 patients, 12 patients were classified as 'psychologically abnormal' (at least one scale with a T-score higher than 70) and 12 as 'normal'. In a quasi-experimental setting, all patients underwent EMG-biofeedback therapy (12 sessions, twice weekly), after a waiting period of six weeks. Clinical symptoms (pressure point sensitivity, secondary symptoms), subjective pain dimensions as well as quality of life were assessed before and after the waiting period, immediately after the biofeedback training and at a three month follow up. RESULTS: Within the 'psychologically abnormal' patients primarily depressive, hypochondriacal and hysterical symptoms were found. Statistical evaluation showed that 'psychologically normal' patients experience long-term relief from pain measured in terms of pressure point sensitivity; vitality and mental health. 'Psychologically abnormal' patients, on the other hand, showed improvements in all the measured parameters (clinical symptoms, sensory and affective pain components, quality of life) after EMG-biofeedback. Long-term improvement, however, was observed only in pressure point sensitivity and the sensory pain dimension. CONCLUSION: The results suggest, that assessment of FM-patients should not only consist of commonly used ACR diagnostic criteria but should also include psychodiagnostic criteria, as these may co-determine treatment outcome. One approach to treating FM patients with additional psychological abnormality might be combining EMG-biofeedback that enhances self-efficacy with psychotherapy that helps patients to become aware of their basic psychological problems.

Type 2 diabetes. How new insights, new drugs are changing clinical practice.

In 1997, the American Diabetes Association recommended a normal fasting blood glucose of < 126 mg/dL as the criteria for diagnosis of type 2 diabetes. Since then, new data have suggested that post-prandial glucose may have a stronger correlation with cardiovascular disease than fasting blood glucose. Two trials, the DCCT and UKPDS, provided evidence of the relationship between hyperglycemia and long-term diabetic complications. Preventing short-term complications, such as cognitive decline, is a more immediate goal and less well-studied. Type 2 diabetes is understood to result most often from insulin resistance and insulin deficiency. New classes of drugs offer expanded therapeutic options for managing this dual metabolic defect. These drugs have invalidated the former therapeutic paradigm of diet, sulfonylureas, and then insulin therapy.

Proarrhythmia of azimilide and other class III antiarrhythmic agents in the adrenergically stimulated rabbit.

The ventricular proarrhythmic actions of five class III antiarrhythmic agents were compared in the Carlsson rabbit model. In adrenergically stimulated anesthetized rabbits, azimilide, clofilium, dofetilide, sematilide, and d,l-sotalol caused premature ventricular contractions and nonsustained and sustained ventricular tachyarrhythmias (NSVT and SVT) at pharmacologically equivalent intravenous doses that increased QTc intervals 20% (ED20). There were no significant differences between agents in the percentage of rabbits with serious arrhyhthmias at the ED20 doses of 5.2, 0.033, 0.015, 0.66, and 2.8 mg/kg i.v., respectively. Proarrhythmia was dose-dependent. Linear regression analysis of arrhythmia score versus log dose estimated the NSVT doses as 6.2, 0.055, 0.0089, 1.5, and 5.7, respectively. Analysis of arrhythmia states during a 10-min window after infusion when QTc prolongation was 20% showed that the compounds differed significantly in the proportion of time treated rabbits spent in SVT and combined NSVT and SVT. Rabbits treated with azimilide spent significantly less time in SVT and combined NSVT and SVT, followed in order of increasing time by d,l-sotalol, sematilide, clofilium, and dofetilide.

[Electromyography biofeedback therapy in fibromyalgia]. / EMG-Biofeedback-Therapie bei Fibromyalgie.

Nineteen patients with fibromyalgia underwent a course of treatment with EMG-biofeedback (EMG-BFB) technique. On completion of treatment, there was a statistically significant lowering of sensitivity to pain at pressure points typical for fibromyalgia (p = 0.017), which could be observed also 2 months after completion of treatment. In addition, there was a reduction both in the affective (p = 0.04) and in the sensory (p = 0.007) components of pain. Furthermore, there was a statistically significant improvement in the accompanying disease parameters of sleep disturbance (p = 0.004) and head ache (p = 0.031). Since EMG-BFB training might contribute not only to a reduction of pain and muscle tension but also to an improvement of quality of life, it can be recommended as part of a multimodal pain therapy in fibromyalgia patients.

Efficacy of total parenteral nutrition in a series of end-stage AIDS patients: a case-control study.

The aims of this study were to document the risks and benefits of total parenteral nutrition (TPN) by comparing two groups of patients with advanced HIV disease. This case-control study took place from June 1992 through June 1994. Medical Records were the primary source of data. Bailey-Boushay House, a 24-h skilled nursing facility in Seattle, Washington was the resident location of participating patients. TPN was commonly used in this long-term care facility for persons with AIDS. Eighty patients with AIDS, 40 of whom were receiving TPN and 40 of whom were not receiving TPN but who had central venous access (control group) were chosen. No significant differences were found between the two groups in the number of positive blood cultures (10% vs. 3%), however, the number of abnormal lab values was higher in the TPN group (6 vs. 4) (p < 0.05). The TPN group also gained an average of 2.2 kg in weight compared to an average loss of 1.4 kg in the control group (p < 0.05); the control group had a higher number of patients with weight loss > 10% of admit weight (28% vs. 8%) (p < 0.05). The length of stay was similar between groups (91 vs. 77 days), as were several quality of life indicators. The conclusions of the investigators was that TPN did not appear to lead to clinically important positive or negative health effects when compared to a group not receiving TPN but with central venous access. Benefits or detriments to certain sub-groups of AIDS patients may well exist that were not apparent in this study.

Suppression of inducible ventricular arrhythmias by intravenous azimilide in dogs with previous myocardial infarction.

The class III antiarrhythmics azimilide dihydrochloride and dl-sotalol were evaluated for ability to suppress induction of ventricular tachyarrhythmias (VT) in anesthetized, male mongrel dogs 4-6 days after surgical infarction of the left ventricle (LV) produced by ligation/reperfusion of the left anterior descending coronary artery. Postmortem infarcts averaged 28.2 +/- 3.3% and 27.5 +/- 3.9% of the LV for azimilide- and sotalol-treated dogs, respectively. Both agents (0.3-30 mg/kg i.v.) increased ventricular effective refractory period as a function of dose in LV normal and infarcted zones without increasing conduction time. Azimilide was well tolerated hemodynamically up to 30 mg/kg i.v., whereas sotalol produced a significant and dose-related decrease in both blood pressure and heart rate. Azimilide was effective in five (56%) of nine dogs in preventing induction of ventricular arrhythmias by programmed electrical stimulation (PES) at doses from 1 to 30 mg/kg. Efficacy was seen for nonsustained and sustained VT and for ventricular fibrillation. Although sotalol (0.3-10 mg/kg) was effective in all five VT dogs tested, one of two nonsustained ventricular tachyarrhythmia (NSVT) dogs and two of three sustained ventricular tachyarrhythmia (SVT) dogs were reinducible with the baseline arrhythmia at doses higher than the effective dose, and one dog died after 30 mg/kg of sotalol. Both agents increased the cycle length of VT. Thus azimilide simultaneously increased refractoriness and provided antiarrhythmic efficacy as suppression of PES-induced ventricular arrhythmias in infarcted dogs without the hemodynamic depression seen with sotalol.

Tumor necrosis factor: its role in HIV/AIDS.

AIDS: Tumor necrosis factor (TNF, cachectin), a cytokine secreted by macrophages and T-cells, mediates inflammatory and immune responses, and is associated with wasting in persons with malignancies or AIDS. In inflammation, TNF attracts and activates neutrophils, stimulating phagocytic function of neutrophils and macrophages. TNF also increases hepatic cell resistance to damaging parasitic effects; enhances endothelial permeability, causing edema; aids in wound healing by stimulating tissue and vascular growth; enhances lymphocytic activity through cytokine activation; acts with interleukin (IL) to produce fever, anorexia, lethargy and sleep; and possesses antitumor activity, particularly against the presumed origin of Kaposi's sarcoma, capillary endothelial cells. The host has an acute phase response (APR) following TNF- and IL-induced immunologic activation. TNF and IL decrease production and activity of lipoprotein lipase (LPL), resulting in reduced uptake and improper storage of fat; and they stimulate anabolism of fatty acids, causing hypertriglyceridemia. This "futile cycling" causes shuttling of fatty acids between adipose tissue and the liver, and use of muscle protein as the main fuel source. This, along with further muscular breakdown due to the increased caloric demands of fever, may affect cachexia. TNF benefits the HIV-infected through selective killing of HIV-infected cells, although effects may be dose and time dependent. The negative effects of TNF may be impeded by anti-cytokine therapy. Possible therapies include dietary N-3 fatty acid (fish oil), an inhibitor of TNF and IL production in vitro; pentoxifylline (Trental), another TNF production inhibitor; anti-TNF monoclonal antibodies; and soluble TNF receptors.^ieng

Patient-reported experience with Velosulin human insulin in continuous subcutaneous insulin infusion.

A multicenter, retrospective survey of 339 patients with insulin-dependent diabetes mellitus was done to evaluate patient experience with Velosulin Human insulin, a regular insulin in a phosphate buffer, used in continuous subcutaneous insulin infusion. Patients had used this insulin exclusively for 3 months preceding the survey. Responses were elicited through interviews conducted by physicians or nurses. Patients were queried as to the occurrence of specific complications associated with pump therapy that occurred while using Velosulin Human insulin, including hypoglycemia, diabetic ketoacidosis, unexplained hyperglycemia, tubing obstruction, and infection or abscess at the infusion site. Most patients reported that they did not experience any of these complications during the preceding 3 months. The most frequently cited complication was hyperglycemia unexplained by dosage, exercise, or dietary changes, reported by 110 (32%) patients. The second most frequently reported complication was tubing obstruction, reported by 99 (29%) patients. The reported frequencies of the other complications were: severe hypoglycemia, 45 (13%) patients; diabetic ketoacidosis, 28 (8%) patients; and infection or abscess at the infusion site, 26 (8%) patients. The low morbidity reported by the patients in this survey probably was due in large part to careful patient selection, a high level of motivation on the part of the patients, and experience and education on the part of the health care team, as well as to the use of buffered regular human insulin.

Long-term prospective study of postpartum thyroid dysfunction in women with insulin dependent diabetes mellitus.

Postpartum thyroid dysfunction (PPTD) is a common autoimmune disorder. Type I diabetes mellitus (IDDM) is an autoimmune disease with a high incidence of concomitant autoimmune thyroid failure. We hypothesized that women with IDDM would have an increased incidence of PPTD. Women with IDDM in New York City, were followed prospectively during the second and third trimester of pregnancy and at 6 weeks, 3 months, 6 months, 9 months, and 1 yr postpartum. A long-term follow-up was performed at 31 months postpartum. Forty-one women with IDDM were recruited at their initial prenatal visit. Two women (4.8%) had thyroid function test abnormalities observed at screening, three (7.3%) had a spontaneous miscarriage, and eight (19.5%) women were noncompliant with follow-up. Twenty-eight women (68.2%) completed the study. Thyroid function tests and thyroid autoantibody determinations were obtained at all visits. PPTD was defined as a TSH greater than 5.0 or less than 0.2 mU/L in the postpartum period with documented normal thyroid function tests during pregnancy. The incidence of PPTD in women with IDDM was 25%. This is a 3-fold increase compared to a similar study by our group in a nondiabetic population. Forty-three percent of the women (3/7) who developed PPTD required treatment in the immediate postpartum period and at long-term follow-up. The remainder of the women with PPTD, as well as all women who did not develop PPTD were euthyroid at 31 months postpartum. Women with IDDM are at high risk for PPTD. We recommend that all women with IDDM be screened for thyroid hormonal abnormalities during pregnancy and at 3 months postpartum for postpartum thyroid dysfunction. Long-term follow-up did not reveal an increased incidence of hypothyroidism in women who did not require treatment in the first postpartum year.

The effects of lipid lowering on diabetic retinopathy.

The effect of lipid lowering on hard exudates was determined in six consecutive patients with insulin-dependent diabetes mellitus. Diet and hypolipidemic drug therapy including the use of pravastatin, a new inhibitor of 3-hydroxy-3-methylglutaryl coenzyme-A reductase, were used to treat patients for one year. The total cholesterol concentration decreased from a mean baseline value of 231 mg/dl to a treatment mean value of 165 mg/dl. The mean low-density lipoprotein cholesterol concentration decreased from 157 mg/dl to 93 mg/dl. Masked grading of fundus photographs indicated an improvement in hard exudates in all six patients and a decrease in microaneurysms in four patients. Visual acuity improved in one patient and did not change (one line or less change) in five patients. No remarkable side effects resulting from treatment were observed. Our pilot study suggests that aggressive therapy of diabetic patients with hyperlipidemia may have a beneficial effect on background retinopathy.

Comparison of the effects of intravenous LNC-834, a new antiarrhythmic agent, and quinidine in canine models of arrhythmia.

The effects of intravenous LNC-834, a new antiarrhythmic agent, and quinidine sulfate were evaluated and compared in 24-h infarction, programmed electrical stimulation (PES), and ventricular fibrillation threshold (VFT) canine models of cardiac arrhythmias. In the 24-h infarction model (24 h after myocardial infarction), animals averaged 85% arrhythmic beats before treatment. LNC-834 gave greater suppression of these spontaneous arrhythmias (97%) and had a longer duration of action (150 min) than did quinidine (70% and 85 min, respectively) at 10 mg of base/kg, although plasma levels were comparable (1.82 +/- 0.19 and 1.50 +/- 0.27 micrograms/ml of plasma for LNC-834 and quinidine, respectively). At 10 mg of base/kg, LNC-834 and quinidine increased effective refractory periods by 9 and 7%, respectively. In the PES model, LNC-834 (3 mg of base/kg) suppressed ventricular tachycardia (VT) in 33% (2/6) of the dogs tested: none of the six quinidine-treated animals displayed suppression of VT at cumulative doses of 0.3 to 30 mg of base/kg. In PES dogs, inducible and noninducible, mortality was less with LNC-834 treatment than with quinidine [9% (1/11) and 36% (4/11), respectively]. Neither LNC-834 nor quinidine elevated VFT in naive, anesthetized dogs. Although no treatment significantly affected the intrinsic heart rate in VFT dogs, both LNC-834 and quinidine produced significant hypotension; however, LNC-834 caused less hypotension than did quinidine at equal doses. This study demonstrates that LNC-834 may be a useful antiarrhythmic agent with efficacy comparable to and hemodynamic advantages over quinidine.

Relation of hemoglobin A1 and blood glucose to cardiac function in diabetes mellitus.

To examine the relation of short- and long-term changes in glucose metabolism to cardiac function, radionuclide cineangiography and echocardiography were performed in 10 young insulin-dependent diabetic patients without clinical evidence of heart disease. Cardiac assessments were performed before and after both acute variations in blood glucose, and induction of chronic "tight glucose control" involving normalization of hemoglobin A1 concentrations. In diabetic patients, left ventricular (LV) ejection fraction (EF) at normal blood glucose concentration was indistinguishable from values in 11 normal subjects. However, during hyperglycemia (about 300 mg/dl), the average EF at rest was 61%, significantly higher than that during normoglycemia (56%, p less than 0.001). No significant change in LV diastolic dimension was noted in association with shifts between high and normal blood glucose concentrations. Normalization of hemoglobin A1 was achieved within 6 to 25 weeks. This alteration had no significant effect on LVEF, mitral valve E-F slope, or the response of systolic function to blood glucose levels. In addition, no correlation was found between LVEF and hemoglobin A1 concentrations in 4 of 5 evaluation periods. Thus, in young insulin-dependent diabetic patients without overt heart disease, variation in blood glucose concentration is associated with small but significant variation in EF at rest; normalization of hemoglobin A1 has no significant effect on LVEF or the response of systolic function to blood glucose levels.

A randomized comparative crossover evaluation of glucose monitoring technologies.

Twenty-four diabetic patients receiving insulin were randomized to 3 groups. Group I began self blood glucose monitoring by meter and switched to visually read strips at 3 months. Group II began self blood glucose monitoring by visually read strips and switched to meter readings at 3 months. Group III monitored urine glucoses for the 6 months of the trial. Professional interaction time was the same for all patients and each patient was placed on the same insulin delivery scheme (3 shots NPH and/or regular). Mean C-peptide levels 6 min following intravenous glucagon was comparable in all 3 groups. Patients monitoring blood glucose showed a significant decrease in glycosylated hemoglobin values (p less than 0.01) from patients monitoring urine at 6 months of the trial. Patients subjectively felt meters were more accurate than visual strips but both groups I and II showed lower glycosylated hemoglobin levels (p less than 0.02 at 6 months) and sequence analysis revealed no sequence effect. The trial confirms that blood glucose monitoring technologies have advantages over urine monitoring in helping patients achieve improved glucose levels. Patients perform equally well in terms of blood glucose "control" whether visually read strips or meters are used for initial teaching or maintenance if patients are instructed appropriately in each methodology. These findings have economic implications for large scale treatment programs.

Nocturnal food-related hyperdipsia in the adult spontaneously hypertensive rat.

Male adult spontaneously hypertensive rats (SHR) ate the same but drank more and had a higher water to food ratio (W:F) than did Wistar-Kyoto (WKY) rats in 24-hr when they had continuous access to standard laboratory pellets and tap water. When rats ate in the day phase of a 12:12 light/dark cycle after 24-hr food deprivation, SHR rats ate and drank the same ad did WKY rats in a 60-min test. When the same rats ate at night after 24-hr food deprivation, however, SHR rats were hyperdipsic: They ate the same as did WKY rats, but SHR rats drank more and had a higher W:F. This relative hyperdipsia reflected the increased ability of ingestion of food to stimulate drinking in SHR, because when food was absent for a 60-min test at night SHR drank the same as did WKY rats. Three dipsogens which are candidate components for eating-elicited drinking in the rat, cellular dehydration, histamine and angiotensin II, elicited drinking differentially in SHR and WKY rats: SHR drank more than did WKY rats in response to (1) cellular dehydration produced by IP hypertonic saline, (2) large doses of SC histamine, and (3) SC angiotensin II. These results demonstrate that SHR exhibit a nocturnal food-related hyperdipsia which may reflect differential sensitivity to stimuli important for eating-elicited drinking such as increased osmolality and endogenous histamine or angiotensin.

The role of insulin purification: an overview.

Besides the obvious toxicity of overdosage and hypoglycemia, insulin administration may also be complicated by a variety of local cutaneous reactions and systemic allergic complications. Although these responses are by no means universal among patients injecting insulin, they may pose significant clinical problems. This is particularly true for the localized skin reactions such as lipoatrophy and the systemic insulin allergy leading to insulin resistance. Most commercially available insulin preparations are extracts of pork or beef pancreas. One approach to reducing insulin complications is to improve the homogeneity of commercial preparations by further purification, which has been afforded by recent technology. A priori, the preparations most resembling human insulin with the fewest contaminants should provide the optimal therapy for diabetic patients. Whether this will prove to be the case remains to be documented.