Bio fuel ash in a road construction: impact on soil solution chemistry.

Limited natural resources and landfill space, as well as increasing amounts of ash produced from incineration of bio fuel and municipal solid waste, have created a demand for useful applications of ash, of which road construction is one application. Along national road 90, situated about 20 km west of Sollefteå in the middle of Sweden, an experiment road was constructed with a 40 cm bio fuel ash layer. The environmental impact of the ash layer was evaluated from soil solutions obtained by centrifugation of soil samples taken on four occasions during 2001-2003. Soil samples were taken in the ash layer, below the ash layer at two depths in the road and in the ditch. In the soil solutions, pH, conductivity, dissolved organic carbon (DOC) and the total concentration of cations (metals) and anions were determined. Two years after the application of the ash layers in the test road, the concentrations in the ash layer of K, SO4, Zn, and Hg had increased significantly while the concentration of Se, Mo and Cd had decreased significantly. Below the ash layer in the road an initial increase of pH was observed and the concentrations of K, SO4, Se, Mo and Cd increased significantly, while the concentrations of Cu and Hg decreased significantly in the road and also in the ditch. Cd was the element showing a potential risk of contamination of the groundwater. The concentrations of Ca in the ash layer indicated an ongoing hardening, which is important for the leaching rate and the strength of the road construction.

Exercise blood pressure response is related to left ventricular mass.

An exaggerated SBP response to exercise has been associated with increased left ventricular (LV) mass in some but not all studies. A total of 43 women and 34 men, aged 55-75 years, without evidence of cardiovascular disease, with a mean resting BP of 142+/-9/77+/-8 mmHg had their BP measured at rest and during maximal treadmill exercise. LV mass was measured using magnetic resonance imaging. LV mass was adjusted for lean body mass, which was assessed by dual energy X-ray absorptiometry. LV mass was within the normal range for the majority of the subjects. Among the resting and exercise BP indices, maximal SBP was the strongest correlate of LV mass (r=0.41, P<0.05). In multivariate analysis, maximal SBP was independently associated with LV mass after adjustment for lean body mass and gender, explaining 3% of the variance (P<0.05). Maximal exercise SBP is a modest but still independent predictor of LV mass in older persons with normal LV mass. These results raise the possibility that the SBP response to maximal exercise is an early marker of LV hypertrophy.

Fitness, fatness and activity as predictors of bone mineral density in older persons.

OBJECTIVES: To determine relationships of bone mineral density (BMD) with fitness, physical activity, and body composition and fat distribution. DESIGN: Cross-sectional. SETTING: General Clinical Research Center, Johns Hopkins Bayview Medical Center, Baltimore, Maryland. SUBJECTS: Men (n = 38) and women (n = 46), aged 55-75 years with high normal blood pressure or mild hypertension but otherwise healthy. METHODS: Aerobic fitness (oxygen uptake) on a treadmill, muscle strength by one-repetition maximum, activity by questionnaire, abdominal obesity by magnetic resonance imaging; anthropometrics, and body composition by dual energy X-ray absorptiometry (DXA) which measured total fat and lean mass, and BMD for the total skeleton, lumbar spine (L1-L4) and total hip. RESULTS: Aerobic fitness did not correlate with BMD. Using multivariate analysis to ascertain independent contributions to the variance in BMD, in women, with adjustment for hormone replacement therapy (HRT), total skeleton BMD was independently related to muscle strength and abdominal total fat; total hip BMD to body weight; lumbar spine BMD to abdominal total fat. HRT also influenced BMD in the lumbar spine. In men, lumbar spine BMD was independently related to abdominal total fat physical activity and total hip BMD related to lower body strength. P < 0.05 for all of these correlations. CONCLUSIONS: Abdominal obesity and muscle strength emerge as predominant correlates of BMD in older persons with stronger relationships seen in women. Body weight and HRT also explained portions of the variance in BMD in women. Whether abdominal obesity is simply a marker for general obesity or has independent protective effects on bone is yet to be determined.

Controlling mechanisms of aluminium in soil solution--an evaluation of 180 podzolic forest soils.

To monitor the level of soil acidification in the county of Värmland in the middle west of Sweden 180 podzolic forest soils were investigated. Soil solutions from four horizons were obtained by centrifugation and the soil was sampled for a determination of the exchangeable pool by extraction. The concentrations of inorganic Al and its fraction of the total Al in solution were greater in the south of the county (up to 50%). The factors influencing the total Al and free inorganic Al3+ in the soil solutions were evaluated. Saturation indices (SI) for five different mineral phases were calculated but none implied equilibrium conditions. The relationships between pAl3+ and pH (in the pH range 4-6.2) gave slopes of about 1, which indicated that ion exchange/complexation reactions may be important for determining the Al3+ concentration in the B and C horizons. In the E horizon solutions complexation with soluble organic acids seemed to be the major factor which influenced the Al3+ activity. The influence of organic matter on Al solubility was supported by partial least square (PLS) regressions.

Aluminium speciation in forest soil solution--modelling the contribution of low molecular weight organic acids.

The concentrations of Al bound to identified low molecular weight organic acids (LMWOAs), phosphate and humic compounds in soil solutions (O1, O2, E, B1 and B2 horizons) from Fennoscandinavian coniferous forest soils were calculated. Two models were evaluated: WHAM (Winderemere Humic Aqueous Model) and a model treating the natural organic acids as monoprotic. The WHAM model was calibrated to find an average charge balance of unity, and then used for Al speciation. This was achieved considering approximately 80% of the natural fulvic acid to be 'active'. For the monoprotic model, constants obtained from previous fitting of soil solution data were used and the model was calibrated using acid/base titrations. The modelling confirms that the low molecular weight acids are important complex formers, binding on average 11-42% (O), 19-20% (E), and 0-30% (B) of the total Al in solution depending on the model used. The monoprotic model yielded higher concentrations than WHAM. Both models predicted that the major part of Al in solution was organically complexed to humic substances and LMWOAs, which was consistent with analytical values of 'quickly reacting' Al (monomenc inorganic forms; 12-14% of Al(tot) on average in the E and B1 solutions). Both models could predict the magnitude of the analytical values (RMSD = 4-5 microM). On average the WHAM model showed a better fit for the E horizon solutions and the monoprotic model for the upper B horizon. The pH dependence of the low molecular weight fraction of Al was modelled in the pH range 3-5.5 for a 'typical' O1 and E solution assuming no other changes in soil solution composition. The extrapolation showed that the models had a different pH dependence. The concentration of Al bound to LMWOAs in WHAM decreased with higher pH while the opposite was seen for the monoprotic model. Also the influence of the concentration of total Al in solution was modelled. The models showed similar trends but for the 'typical' O1 horizon sample the monoprotic model yielded higher concentrations of Al bound to LMWOAs than WHAM.

MRI assessment of LV relaxation by untwisting rate: a new isovolumic phase measure of tau.

Most noninvasive measures of diastolic function are made during left ventricular (LV) filling and are therefore subject to "pseudonormalization," because variation in left atrial (LA) pressure may confound the estimation of relaxation rate. Counterclockwise twist of the LV develops during ejection, but untwisting occurs rapidly during isovolumic relaxation, before mitral opening. We hypothesized that the rate of untwisting might reflect the process of relaxation independent of LA pressure. Recoil rate (RR), the velocity of LV untwisting, was measured by tagged magnetic resonance imaging and regressed against the relaxation time constant (tau), recorded by catheterization, in 10 dogs at baseline and after dobutamine, saline, esmolol, and methoxamine treatment. RR correlated closely (average r = -0.86) with tau and was unaffected by elevated LA pressure. Multiple regression showed that tau, but not LA or aortic pressure, was an independent predictor of RR (P < 0.0001, P = 0.99, and P = 0.18, respectively). The rate of recoil of torsion, determined wholly noninvasively, provides an isovolumic phase, preload-independent assessment of LV relaxation. Use of this novel parameter should allow the detailed study of diastolic function in states known to affect filling rates, such as aging, hypertension, and congestive heart failure.

Occurrence of esophageal granular cell tumors in The Netherlands between 1988 and 1994.

Granular cell tumors (GCT) of the esophagus are rare. The tumor is generally beleived to be of neurogenic origin and shows a malignant course in 2-4% of cases. No unanimity has been reached regarding the management of this tumor. A national survey was conducted on the incidence of GCT of the esophagus, related symptoms, management, and follow-up. A national survey was performed on all newly registered esophageal GCTs in the PALGA system (Dutch register of all pathology diagnoses) for seven consecutive years (1988-1994). Fifty-two new cases (17 men, 35 women; median age 46 years, range 22-77 years) were registered. In 44 cases clinical data could be obtained (survey response 85%). The majority of the GCTs were solitary (42/44) and localized in the distal esophagus (33/44). At endoscopy the size of the tumor was estimated at <5 mm in 50%, 5-10 mm in 25%, and 10-30 mm in 18%. Most patients (40/44) presented with nonspecific gastrointestinal symptoms, only four had dysphagia (tumor size >1 cm). No malignancies were reported. Management of the tumor included excisional biopsy (1/44), endoscopic polypectomy (3/44), and surgical excision (1/44). Endoscopic follow up (1-60 months) in 16 out of 17 patients left untreated showed either a stable tumor size or regression of the tumor. In one case with multiple GCT's a slight tumor growth was seen after a follow-up period of 48 months. Esophageal GCTs in the Netherlands are rare, and mostly diagnosed incidentally. Most patients suffer from nonspecific symptoms; dysphagia occurs only with tumors >1 cm. The usual clinical course of esophageal GCTs is benign. Patients without dysphagia probably do not require routine endoscopic follow-up, provided they are instructed to contact their physician, once dysphagia develops.

Effects of GH and/or sex steroid administration on abdominal subcutaneous and visceral fat in healthy aged women and men.

Aging is associated with reduced GH, IGF-I, and sex steroid axis activity and with increased abdominal fat. We employed a randomized, double-masked, placebo-controlled, noncross-over design to study the effects of 6 months of administration of GH alone (20 microg/kg BW), sex hormone alone (hormone replacement therapy in women, testosterone enanthate in men), or GH + sex hormone on total abdominal area, abdominal sc fat, and visceral fat in 110 healthy women (n = 46) and men (n = 64), 65-88 yr old (mean, 72 yr). GH administration increased IGF-I levels in women (P = 0.05) and men (P = 0.0001), with the increment in IGF-I levels being higher in men (P = 0.05). Sex steroid administration increased levels of estrogen and testosterone in women and men, respectively (P = 0.05). In women, neither GH, hormone replacement therapy, nor GH + hormone replacement therapy altered total abdominal area, sc fat, or visceral fat significantly. In contrast, in men, administration of GH and GH + testosterone enanthate decreased total abdominal area by 3.9% and 3.8%, respectively, within group and vs. placebo (P = 0.05). Within-group comparisons revealed that sc fat decreased by 10% (P = 0.01) after GH, and by 14% (P = 0.0005) after GH + testosterone enanthate. Compared with placebo, sc fat decreased by 14% (P = 0.05) after GH, by 7% (P = 0.05) after testosterone enanthate, and by 16% (P = 0.0005) after GH + testosterone enanthate. Compared with placebo, visceral fat did not decrease significantly after administration of GH, testosterone enanthate, or GH + testosterone enanthate. These data suggest that in healthy older individuals, GH and/or sex hormone administration elicits a sexually dimorphic response on sc abdominal fat. The generally proportionate reductions we observed in sc and visceral fat, after 6 months of GH administration in healthy aged men, contrast with the disproportionate reduction of visceral fat reported after a similar period of GH treatment of nonelderly GH deficient men and women. Whether longer term administration of GH or testosterone enanthate, alone or in combination, will reduce abdominal fat distribution-related cardiovascular risk in healthy older men remains to be elucidated.

Strongyloides stercoralis infection: how to diagnose best?

Four patients are described with a Strongyloides stercoralis infection. Several techniques to diagnose this infection are discussed. The so-called Baermann method is emphasised. Especially in chronic infections the combination of serology and the Baermann method seems the best diagnostic approach. Treatment with albendazole or ivermectin are suggested treatments.

Independent effects of preload, afterload, and contractility on left ventricular torsion.

Shortening of oblique left ventricular (LV) fibers results in torsion. A unique relationship between volume and torsion is therefore expected, and the effects of load and contractility on torsion should be predictable. However, volume-independent behavior of torsion has been observed, and the effects of load on this deformation remain controversial. We used magnetic resonance imaging (MRI) with tagging to study the relationships between load and contractility, and torsion. In ten isolated, blood-perfused canine hearts, ejection was controlled by a servopump: end-diastolic volume (EDV) was controlled by manipulating preload parameters and end-systolic volume (ESV) by manipulating afterload using a three-element windkessel model. MRI was obtained at baseline, two levels of preload alteration, two levels of afterload alteration, and dobutamine infusion. An increase in EDV resulted in an increase in torsion at constant ESV (preload effect), whereas an increase in ESV resulted in a decrease in torsion at constant EDV (afterload effect). Dobutamine infusion increased torsion in association with an increase in LV peak-systolic pressure (PSP), even at identical EDV and ESV. Multiple regression showed correlation of torsion with preload (EDV), afterload (ESV), and contractility (PSP; r = 0.67). Furthermore, there was a close linear relationship between torsion and stroke volume (SV) and ejection fraction (EF) during load alteration, but torsion during dobutamine infusion was greater than expected for the extent of ejection. Preload and afterload influence torsion through their effects on SV and EF, and there is an additional direct inotropic effect on torsion that is independent of changes in volume but rather is force dependent. There is therefore potential for the torsion-volume relation to provide a load-independent measure of contractility that could be measured noninvasively.

Determination of low molecular weight organic acids in soil solution by HPLC.

An HPLC method employing an ion exclusion column was developed for the determination of low molecular weight organic acids in soil solution. The method includes extensive sample pretreatment using ultrafiltration and cation exchange. The method showed linear calibration graphs (r>0.99) and the limits of detection in the range 0.1-26 muM. The recovery of eleven added acids ranged from 89 to 102%. Soil solutions of five horizons of a podzolised soil were analysed. The results showed that these compounds made up 1-3% of the dissolved organic carbon and 0-14% of the acidity. Identification of the major acids was also carried out by capillary zone electrophoresis.

Noninvasive measurement of shortening in the fiber and cross-fiber directions in the normal human left ventricle and in idiopathic dilated cardiomyopathy.

BACKGROUND: Studies in anesthetized dogs have shown that myocardial fibers shorten approximately 8%. However, in the endocardium, shortening occurs to a much greater extent at 90 degrees to the fiber orientation ("cross-fiber shortening") than it does along the fiber direction. The purpose of this study was to estimate the extent of fiber and cross-fiber shortening in the normal human left ventricle and in patients with idiopathic dilated cardiomyopathy (IDC). METHODS AND RESULTS: Ten normal subjects and nine patients with IDC were imaged with magnetic resonance tissue tagging. Finite strain analysis was used to calculate endocardial and epicardial shortening in the fiber and cross-fiber directions using anatomic fiber angles from representative autopsy specimens as references. Anatomic fiber angles were not different between normal subjects and IDC patients. Epicardial fiber strain was -0.14+/-0.01 in normal subjects and -0.08+/-0.01 in IDC patients (P<.0001 versus normal subjects). Epicardial cross-fiber strain was -0.08+/-0.01 in normal subjects and -0.06+/-0.01 in IDC patients (P=NS). Endocardial fiber strain was -0.16+/-0.01 in normal subjects and -0.09+/-0.01 in IDC patients (P<.0001), and endocardial cross-fiber strain was -0.26+/-0.01 in normal subjects and -0.15+/-0.01 in IDC patients (P<.0001). Cross-fiber shortening was greater than fiber shortening at the endocardium in both normal subjects (P<.0001) and IDC patients (P<.05). CONCLUSIONS: In normal humans, the direction of maximal deformation aligns with the fiber direction in the epicardium but is perpendicular to the fiber direction in the endocardium. When strain in a coordinate system aligned to the fibers is estimated, cross-fiber shortening is found to be the dominant shortening strain at the endocardium. Normal fiber shortening is 15%, and this is markedly reduced in IDC. The normal transition in fiber orientation through the wall is not altered in IDC, and cross-fiber shortening is still the dominant strain at the endocardium, suggesting that interactions between myocardial layers persist in these patients.

Effects of afterload on regional left ventricular torsion.

OBJECTIVE: To determine if left ventricular torsion, as measured by magnetic resonance tissue tagging, is afterload dependent in a canine isolated heart model in which neurohumoral responses are absent, and preload is constant. METHODS: In ten isolated, blood perfused, ejecting, canine hearts, three afterloads were studied, while keeping preload constant: low afterload, high afterload (stroke volume reduced by approx. 50% of low afterload), and isovolumic loading (infinite afterload). RESULTS: There were significant effects of afterload on both torsion (P < 0.05) and circumferential shortening (P < 0.0005). Between low and high afterloads, at the anterior region of the endocardium only, where torsion was maximal, there was a significant reduction in torsion (15.1 +/- 2.2 degrees to 7.8 +/- 1.8 degrees, P < 0.05). Between high afterload and isovolumic loading there was no significant change in torsion (7.8 +/- 1.8 degrees to 6.2 +/- 1.5 degrees, P = NS). Circumferential shortening at the anterior endocardium was significantly reduced both between low and high afterload (-0.19 +/- 0.02 to -0.11 +/- 0.02, P < 0.0005), and also between high afterload and isovolumic loading (-0.11 +/- 0.02 to 0.00 +/- 0.02, P < 0.05). Plots of strains with respect to end-systolic volume demonstrated a reduction in both torsion and shortening with afterload-induced increases in end-systolic volume. Torsion, but not circumferential shortening, persisted at isovolumic loading. CONCLUSIONS: Maximal regional torsion of the left ventricle is afterload dependent. The afterload response of torsion appears related to the effects of afterload on end-systolic volume.

Low-amplitude distal esophageal spasm as a cause of severe dysphagia for solid food.

This case report presents a patient with progressive dysphagia, accompanied by weight loss, in the absence of organic disease. Esophageal motility studies initially failed to reveal a diagnosis. At simultaneous manometry and fluoroscopy, with bread/barium boluses, the diagnosis of esophageal spasm in a relatively weak esophagus was made. All conservative treatment modalities failed. Thoracoscopic myotomy resulted in partial field of symptoms. Finally, an esophagectomy was performed because of sever dysphagia accompanied by persisting weight loss.

Comparison of the efficacy and safety of 1.5 compared with 3.0 g oral slow-release mesalazine (Pentasa) in the maintenance treatment of ulcerative colitis. Dutch Pentasa Study Group.

OBJECTIVE: To investigate a possible dose-effect relationship with two dosages of oral slow-release mesalazine in patients with quiescent ulcerative colitis. METHOD: One hundred and sixty-nine patients with ulcerative colitis in remission were treated with either 1.5 or 3.0 g/day mesalazine for 1 year or until relapse into active colitis. RESULTS: Fewer of the 3.0 g dose group relapsed than of the 1.5 g dose group (33 compared with 46%). This difference failed to reach statistical significance (P = 0.057). A significant relationship between age and relapse rate was established. No dose-related adverse events were found. Three serious drug-related adverse events were, however, reported. All of the serious adverse reactions resolved after the medication was discontinued. CONCLUSION: There is a trend for high doses of oral mesalazine to be more effective in prevention of relapse of ulcerative colitis. These higher doses are not associated with a higher incidence of adverse reactions.

Assessment of changes in murine tumor oxygenation in response to nicotinamide using 19F NMR relaxometry of a perfluorocarbon emulsion.

The oxygen dependencies of the 19F NMR spin-lattice relaxation rates (R1 = 1/T1) of a perfluorocarbon emulsion sequestered in a murine tumor model has been used to evaluate nicotinamide, a radiosensitizer believed to act through enhanced tissue oxygenation. Fluorine-19 NMR spectroscopic measurements from solid Radiation-Induced Fibrosarcoma (RIF-1) tumors in C3H mice showed a statistically significant improvement in tumor pO2 for a Nicotinamide-treated group, with a delta pO2 = 4.7 +/- 3 torr ( = mm Hg) (Mean +/- SEM) at t = 60 min (P < .01), and 4.5 +/- 3 at t = 70 min post intraperitoneal injection (P < 0.02) as compared with saline-treated Controls, while several other time points for which t > 30 min were significant at the P < 0.05 level. Both groups had n = 10, and the statistics were based on Student's one-tailed group t test. By comparison, in another study group where breathing gas was switched from air to 100% O2, a statistically insignificant increase of 2 torr was realized in tumor pO2 (n = 9). The maximal treatment effect occurs at a delay of 60 to 70 min, consistent with results obtained by other investigators using radiobiology techniques. Fluorine-19 spectroscopic relaxometry can measure therapeutically meaningful changes in in vivo tumor pO2 and represents an improvement in expenditures of time, animal resources, and statistical power over conventional radiobiological methods.

A new perfluorocarbon for use in fluorine-19 magnetic resonance imaging and spectroscopy.

A new perfluorocarbon, PTBD (perfluoro-2,2,2',2'-tetramethyl-4,4'-bis(1,3-dioxolane)), is described for use in 19F MR imaging and spectroscopy. Two-thirds of the molecular fluorine in PTBD resonates at a single frequency and can be imaged without the use of frequency-selective spin-echo (SE) MRI pulse sequences to suppress chemical shift artifacts. The absence of strong homonuclear spin-spin coupling to the imagable -CF3 groups in PTBD minimizes signal attenuation in 19F SE MRI due to J-modulation effects. For equimolar concentrations of perfluorocarbon, PTBD gives an approximately 17% increase in sensitivity, relative to literature results for perfluorinated amines, at short values of TE (approximately 10 ms) in 19F SE MRI. These attributes allow 19F MRI of PTBD to be performed on standard clinical imaging instrumentation (without special hardware and/or software modification) and an in vivo example in a mouse is shown. This investigation involved characterizing the MR T1 and T2 relaxation times of PTBD as well as the MR spin-lattice relaxation rate, R1 (1/T1), of PTBD as a function of dissolved oxygen concentration. The T1 and T2 relaxation times and R1 relaxation rates of perfluorooctyl bromide (PFOB) were also obtained, under similar experimental conditions, to compare and contrast PTBD with a representative perfluorocarbon that has been widely employed for 19F MRI/MRS applications.

Sulphasalazine-induced eosinophilic pneumonia.

Eosinophilic pneumonia and skin rash developed in a 21-yr-old man while taking sulphasalazine. After discontinuation of the drug and treatment with steroids the pulmonary infiltrates and rash resolved completely. A short review of the literature concerning sulphasalazine-induced lung disease is presented.

Application of magnetic resonance imaging to physiologic and morphologic characterization of renal artery stenosis before and after angioplasty.

This study describes the application of dynamic gadolinium-enhanced magnetic resonance (MR) imaging and MR angiography in the diagnosis and evaluation of the physiology of renal artery stenosis (RAS) before and after angioplasty. The MR imaging findings are discussed and compared to those of renal arteriography. MR time intensity curves of the renal cortex and medulla are obtained. Dynamic gadolinium-enhanced and angiographic MR data were abnormal in the setting of RAS and improved after angioplasty. The diagnosis of RAS could be made by visual inspection of MR dynamic images or MR angiographic images alone. Dynamic MR provides cross-sectional physiologic imaging data that compliments MR angiographic data. The role of dynamic gadolinium-enhanced MR in the evaluation of renovascular hypertension requires further investigation.