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The newly synthesized discotic dimer, bis(pentakis(pentyloxy)triphenylenyloxy)decane (DTHE5) is structurally and mesomorphically similar to monomer interims of association between spacer and free alkyl chains and spacer length. X-ray diffraction studies confirm the assignment of a THE5 muscle discotic phase and yield lattice parameters. Deuterium NMR spectroscopy of DTHE 5 reveals line shapes related to monomeric subunit-based, restricted, high-amplitude planar vibrations.

Long term data series (1996-2009) for eleven acidic, headwater streams (<10 km²) in Sweden were analyzed to determine factors controlling concentrations of trace metals. In-stream chemical data as well climatic, flow, and deposition chemistry data were used to develop models predicting concentrations of chromium (Cr), lead (Pb), and zinc (Zn). Data were initially analyzed using partial least squares to determine a set of variables that could predict metal concentrations across all sites. Organic matter (as absorbance) and iron related positively to Pb and Cr while pH related negatively to Pb and Zn. Other variables such as conductivity, manganese, and temperature were important as well. Multiple linear regression was then used to determine minimally adequate prediction models which explained an average of 35% (Cr), 52% (Zn), and 72% (Pb) of metal variation across all sites. While models explained at least 50% of variation in the majority of sites for Pb (10) and Zn (8), only three sites met this criterion for Cr. Investigation of variation between site models for each metal revealed geographical (altitude), chemical (sulfate), and land use (silvaculture) influences on predictive power of the models. Residual analysis revealed seasonal differences in the ability of the models to predict metal concentrations as well. Expected future changes in model variables were applied and results showed the potential for long term increases (Pb) or decreases (Zn) for trace metal concentrations at these sites. [ABSTRACT FROM AUTHOR]

Thirty-two patients (10 male, 22 female; age 37–82 years) undergoing maintenance haemodialysis or haemofiltration were studied by means of Holter device capable of simultaneously analysing rhythm and ST changes in three leads. Twenty-five patients were on haemodialysis, seven on haemofiltration, mean duration of haemodialysis/haemofiltration being 3.4±3 years. Incidence of ventricular tachycardia was low, being detected only in 1 of 32 patients. Ventricular premature beats in excess of 10/h during a period of 2 h were found in 8 of 32 patients and 100 supraventricular premature beats for 2 h or more in 4 of 32 patients. Both ventricular premature beats and supraventricular premature beats were most frequently recorded during the last hour of haemodialysis/haemofiltration. ECG signs of ischaemia were detected in eight patients, four of whom were asymptomatic. Ischaemia also occurred predominantly during the last hour of haemodialysis/haemofiltration. Two symptomatic patients displayed neither arrhythmias nor ST-changes while being monitored. The study shows that silent ischaemia and arrhythmias in patients under going chronic haemodialysis/haemofiltration may not be infrequent. Recognition of these events could be of importance in the management of these patients. [ABSTRACT FROM PUBLISHER]

Temporal trends for concentrations of mercury (Hg), lead (Pb) and cadmium (Cd) were evaluated from year 2000-2020 in 20 (Hg), 23 (Pb) and 11 (Cd) watercourses in remote forest catchments in Europe. Decreasing trends were observed in 15% (Hg), 39% (Pb) and 45% (Cd) of the watercourses during the period of evaluation. Decreasing trends were mainly observed between 2000 and 2005 for Hg and between 2000 and 2015 for Pb and Cd. For the last five years of the studied time period (2015-2020), more watercourses showed significant increasing, rather than decreasing Hg, Pb and Cd trends. This was interpreted as a legacy effect of metals still retained in catchment soils. The overall negative trends during the earlier part of the study period were likely driven by declining deposition of metals over Europe, especially for Pb and Cd. Other changes related to metal transport and chemistry may have contributed to the observed trends as well, including recovery from acidification and the ongoing browning of surface waters at northern latitudes. Here we found that organic carbon could explain the seasonal variation in Hg and Pb, but was not related the interannual trends. This study highlights the need for long-term monitoring and robust statistical methods that can detect multidirectional, long-term change in water chemistry., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Phosphorus (P) is often a limiting nutrient in freshwaters and most management actions aim to reduce eutrophication associated with excess anthropogenic P inputs. Here, we report on the opposite problem, persistent and widespread oligotrophication (i.e., declining P concentrations) in northern rivers (56 o -66 o N) that appears unrelated to reductions in anthropogenic loading. Over the past forty years, P concentrations and fluxes in rivers draining forest dominated Swedish catchments have declined by nearly 50 %, with steeper declines in nutrient poor locations. Trends are negatively correlated with forest growth, temperature, pH and alkalinity. They are unrelated to trends in calcium, organic carbon and runoff. Declining P trends were strongest in locations draining catchments with shallow, nutrient poor soils and P concentrations in most locations are currently below estimated reference levels. These widespread and ongoing P declines highlight the need for new surface water management paradigms addressing the consequences of both nutrient scarcity and surplus., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Martyn Futter reports financial support was provided by the Swedish Environmental Protection Agency. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

For more than 50 years, aluminum (Al)-salts have been used with varying degrees of success to inactivate excess mobile phosphorus (P) in lake sediments and restore lake water quality. Here, we analyzed the factors influencing effectiveness and longevity of Al-treatments performed in six Swedish lakes over the past 25 years. Trends in post-treatment measurements of total phosphorus (TP), Chlorophyll a (Chl&#95;a), Secchi disk depth (SD) and internal P loading rates (Li) were analyzed and compared to pre-treatment conditions. All measured water quality parameters improved significantly during at least the first 4 years post-treatment and determination of direct effects of Al-treatment on sediment P release (Li) was possible for three lakes. Improvements in TP (-29 to -80%), Chl&#95;a (-50 to -78%), SD (7 to 121%) and Li (-68 to -94%) were observed. Treatment longevity, determined via decreases in surface water TP after treatment, varied from 7 to >47 years. Lake type, Al dose, and relative watershed area were related to longevity. In addition, greater binding efficiency between Al and P was positively related to treatment longevity, which has not previously been shown. Our findings also demonstrate that adequate, long-term monitoring programs, including proper determination of external loads, are crucial to document the effect of Al-treatment on sediment P release and lake water quality., (Copyright © 2021. Published by Elsevier Ltd.)

Historical accumulation of phosphorus (P) in lake sediment often contributes to and sustains eutrophic conditions in lakes, even when external sources of P are reduced. The most cost-effective and commonly used method to restore the balance between P and P-binding metals in the sediment is aluminum (Al) treatment. The binding efficiency of Al, however, has varied greatly among treatments conducted over the past five decades, resulting in substantial differences in the amount of P bound per unit Al. We analyzed sediment from seven previously Al treated Swedish lakes to investigate factors controlling binding efficiency. In contrast to earlier work, lake morphology was negatively correlated to binding efficiency, meaning that binding efficiency was higher in lakes with steeply sloping bathymetry than in lakes with more gradually sloping bottoms. This was likely due to Al generally being added directly into the sediment, and not to the water column. Higher binding efficiencies were detected when Al was applied directly into the sediment, whereas the lowest binding efficiency was detected where Al was instead added to the water column. Al dose, mobile sediment P and lake morphology together explained 87% of the variation in binding efficiency among lakes where Al was added directly into the sediment. This led to the development of a model able to predict the optimal Al dose to maximize binding efficiency based on mobile sediment P mass and lake morphology. The predictive model can be used to evaluate cost-effectiveness and potential outcomes when planning Al-treatment using direct sediment application to restore water quality in eutrophic lakes., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 The Authors. Published by Elsevier Ltd.. All rights reserved.)

The major stimulus for atrial natriuretic peptide (ANP) release is atrial stretch and increased values are observed in volume overload states such as chronic renal failure. Since successful kidney transplantation restores volume homeostasis, we compared the effects of human cadaveric kidney transplantation on time course and changes of plasma ANP in the early postoperative period in 4 patients with successful and 4 patients with failed transplantation. ANP concentrations were elevated before transplantation in both groups (91 +/- 16 and 70 +/- 32 pmol/l) and decreased after successful (50 +/- 27 pmol/l, day 16) but increased after failed transplantation (146 +/- 45 pmol/l, day 16). Moreover, there was a close correlation between changes of body weight and ANP concentrations. Plasma renin activity decreased and plasma noradrenaline increased non-significantly in both groups, the latter more so after failed transplantation (116 +/- 42 to 194 +/- 156 vs 156 +/- 157 to 425 +/- 287 ng/l). No correlation was found between changes of renin activity or plasma catecholamines and ANP concentrations. The results indicate that the mechanisms governing release of atrial natriuretic peptide are operative in patients with chronic end-stage renal failure and after successful kidney transplantation with a return of atrial natriuretic peptide concentrations towards normal in the latter.

261 patients who received a kidney transplant under cyclosporin-A immunosuppression were reviewed in order evaluate the benefits and the risks of renal graft biopsies. 240 graft biopsies were performed in 124 of the 261 patients. The biopsy diagnoses were 103x rejection, 90x cyclosporin-A toxicity, 8x acute tubular necrosis, 8x glomerulonephritis, 9x different biopsy results, and 12 cases of normal renal tissue. In 214 cases the clinical course was well explained by the biopsy result. The histological results led to therapeutical changes in 199 cases. 221 of the 240 biopsies were performed without any complications. There was only one biopsy with irreversible and there were 19 biopsies with reversible complications.

Twelve consecutive first cadaveric kidney transplant recipients received cyclosporine G (CsG)(initial dose 12 mg/kg per day) as basic immunosuppressive treatment along with prednisone (initial dose 0.5 mg/kg per day) for the first three months after transplantation. Thereafter CsG was replaced by Sandimmun (cyclosporine, CsA). Evaluation of the immunosuppressive efficacy and assessment of possible side effects of CsG was made and compared with the results in 38 historical control patients starting with the same dose of CsA as part of the same immunosuppressive dosage schedule. Statistically, there was no difference in patient survival at three (91% in CsG group versus 95% in CsA group) and twelve months (91% in CsG group versus 92% in CsA group), or in graft survival at three (75% in CsG group versus 89% in CsA group) and twelve months (75% in CsG group versus 84% in the CsA group). At equivalent oral doses of CsG and CsA significantly higher blood levels of CsG were observed (2P less than 0.05). Nephrotoxicity assessed by graft biopsy could be demonstrated to a similar extent in both groups, whereas hepatotoxicity was more pronounced during CsG treatment. Sequential measurements of bilirubin revealed a significant increase in all patients but median values were significantly higher in the CsG patients. A pronounced and concordant elevation of liver enzymes occurred during CsG treatment in three out of 12 patients. Liver biopsies performed in these patients revealed histological alterations consistent with toxic liver injury. Thus, in human kidney transplant recipients CsG and CsA appeared to be equally immunosuppressive and nephrotoxic but more hepatotoxic. On the basis of this limited experience we conclude that in human kidney transplant recipients CsG has no advantage over CsA.

A method is described for distinguishing between graft rejection and cyclosporin nephrotoxicity in renal allograft recipients by analyzing fresh morning urine samples. The technique combines classic Papanicolaou with immunocytochemical staining and was performed in urine specimens from a series of 42 patients. Early-stage cyclosporin toxicity was usually associated with increased numbers of proximal tubular cells only, whereas in rejection and late-stage toxicity there were increases in both tubular cells and in lymphocytes and monocytes (greater than 2000 cells/ml urine). Differentiation between these two clinical conditions was achieved by immunostaining, which revealed that increased numbers of CD25+ and CD8+ cells, as well as an increase in the HLA-DR/Lu5 ratio, were typical of rejection. CD25 positivity proved to be the best indicator of rejection, with a sensitivity and specificity of more than 90%. A cytodiagnostic algorithm is presented that is based on cell numbers and types, including immunophenotypes. The proposed method has the advantage of being noninvasive and appears to represent a reliable and rapid adjunct for the monitoring of graft function, especially in high-risk patients on cyclosporin immunosuppression.

23 living related kidney transplant donors were prospectively studied to determine the degree of hyperfiltration which occurs after uninephrectomy and to monitor potential consequences of this procedure such as hypertension, microalbuminuria or renal functional impairment. Standard inulin and PAH clearance studies were performed immediately before (n = 23), one week after (n = 22) and one year after nephrectomy (n = 12). Hyperfiltration was defined as the ratio of (post-nephrectomy inulin clearance)/(0.5 x pre-nephrectomy inulin clearance), hyperperfusion was defined in an analogous way for PAH clearance. One week after uninephrectomy, hyperfiltration averaged 134 +/- 6% (SEM) and hyperperfusion was 138 +/- 6%. The degree of hyperfiltration did not correlate with donor age. One year after nephrectomy, hyperfiltration was nearly unchanged (130 +/- 7%) whereas hyperperfusion had significantly decreased to 119 +/- 8% (p less than 0.05). Blood pressure did not increase after nephrectomy and no new cases of hypertension were observed during follow-up. In contrast, there were two new cases of microalbuminuria at one week and one year after nephrectomy. Further follow-up of these kidney donors is warranted.

The extreme lack of renal grafts for transplantation stimulated us to analyze how strict the selection criteria of kidney donors must be. We investigated therefore if preexisting lesions in renal grafts influence initial and late renal function. 147 zero-hour biopsies of 101 donors (mean age 33, from 6-64 years) were examined. By ligh microscopy 38% of biopsies showed no, 44% showed nonspecific and 18% specific lesions. Nonspecific lesions comprised intimal fibrosis of small arteries in 44%, interstitial fibrosis in 8% and an arteriolar hyalinosis in 29%. Out of 102 immunohistologically examined biopsies 74.5% showed nonspecific IgM/C3 deposits in glomeruli and/or arterioles. An age dependent decrease of normal renal biopsies was found which was most evident in donors older than 40 years. Specific findings consisted of glomerulosclerosis (n = 4), glomerulonephritis (n = 11), intravascular coagulation (n = 10) and eclamptic kidney (n = 1). In case of nonspecific immunohistologic findings and in glomerulonephritis rebiopsies showed that antigen deposits usually disappeared within 4 months. Independent of morphologic findings 82% of transplant recipients had a good initial and late renal function. Since donor age, glomerulosclerosis, glomerulonephritis, intravascular coagulation or eclamptic changes seem not to compromise renal function after transplantation a more liberal choice of donors should be considered.

Oral hairy leukoplakia was initially reported only in HIV-infected patients and was considered pathognomonic for HIV infection. The presence of Epstein-Barr virus and the decrease in Langerhans cells seem to be necessary for the development of oral hairy leukoplakia. HIV antigen is not present in oral hairy leukoplakia. We report on seven renal transplant recipients with oral hairy leukoplakia. In six of these patients no HIV infection was present. All patients showed marked immunosuppression following a vigorous immunosuppressive regimen. Five patients each had several rejection episodes, which were treated with further immunosuppressive therapy in addition to the basic immunosuppressive regimen. One patient was infected with HIV from the renal graft and another suffered from liver cirrhosis with portal hypertension caused by chronic hepatitis B infection. We believe that oral hairy leukoplakia is a marker for severe immunosuppression that is not necessarily associated with HIV infection. Organ transplant recipients undergoing dermatological check-up should be examined for oral hairy leukoplakia.

We report on two brothers with adult polycystic kidney disease, malignant teratomas and other genital malformations. Because of the unusual accumulation of malformations of embryologically related organs, we postulate a connection between malformations of the kidneys and the genital tract, on the one hand, and teratomas on the other. No genetic coherence is known so far. It is unlikely that immunosuppression with cyclosporin after transplantation had caused these tumours.

Various thrombosis related parameters of the hemostatic system were evaluated in 11 patients who had had bone marrow transplantation (BMT). At 0, 1, 3 and 6 months after BMT, antithrombin III, heparin cofactor II, protein S (PS), factor VIII:C, von Willebrand factor (vWF:Ag, vWF:RiCof), tissue plasminogen activator (tPA), plasminogen activator inhibitor, thrombin antithrombin III complexes (TAT), d-dimers (DD) and antiphospholipid antibodies (APA) were determined. A statistically significant rise in the levels of vWF was observed after BMT, with a similar trend for tPA. High TAT and/or DD were detected in 10/11 patients and positive APA only in 5/11. Of the other parameters only free PS was permanently low, with normal total PS and C4bBP. These findings suggest persistent thrombin generation peri- and post-BMT. The significantly high vWF and the low free PS could foster a procoagulant state.

In 17 consecutive cadaver kidney transplant recipients treated with cyclosporine (CsA) and steroids, the median of antigenic and functional levels of von Willebrand factor (vWF) and factor VIII (FVIII) before transplantation were elevated (vWF:Ag: 206%, vWF:RCof: 202%; FVIII:Ag: 248%, FVIII:C: 224%; normal values 50-150%). Sequential measurements after transplantation and during CsA treatment revealed a transient significant increase of median values with highest amounts of vWF:Ag of 362% (2 p less than 0.0001), FVIII:Ag of 398% (2 p less than 0.001) and FVIII:C of 360% (2 p less than 0.0001) (Friedman test). vWF:RCof did not show statistically significant changes. After 4 months, levels of vWF and FVIII comparable to those obtained before transplantation were observed. In univariate statistical analysis no correlation was found between vWF of FVIII on the one hand and plasma creatinine levels, CsA dose or CsA whole blood through levels on the other hand. However, multivariate statistics revealed to some extent a positive influence of CsA blood levels on vWF:Ag levels. Patients with vascular rejection or chronic CsA nephrotoxicity showed significantly lower levels of vWF:Ag as compared with patients without endothelial cell damage in the kidney (2 p less than 0.05). However, the difference in vWF:Ag levels already existed before transplantation. In contrast to recent reports, plasma vWF levels were not indicative of vascular injury in kidney graft recipients nor was the marked elevation of vWF and FVIII associated with thromboembolic complications ascribed to CsA treatment.

We have studied 39 patients with asymptomatic microhematuria (AM) over a mean period of 3.7 years (2.6 to 5.3). In 28 patients, the etiology of the AM had remained unknown despite extensive work-up at the time of AM diagnosis. During follow-up, the urine was examined by the dipstick method and a urine sediment was prepared by standard techniques. Erythrocyturia was judged as grade I or grade II (3-9 or less than 9 erythrocytes/hpf) and classified by phase-contrast microscopy as glomerular or non-glomerular (greater than 30% or less than 30% of erythrocytes with glomerular characteristics). The results were as follows. All patients were in good health during the whole follow-up. None developed significant proteinuria or gross hematuria. AM persisted in 28 of the 39 patients (72%) and in 22 of the 28 with AM of unknown etiology (79%). Persistence of AM was independent of grade and morphology of AM. Among the patients with AM of unknown cause, the fifteen who initially showed grade I AM had grade I AM in 92% and grade II AM in 8% of follow-up urinalyses, and the seven with grade II AM at the first examination had grade II AM in 65% and grade I AM in 35% of follow-up urinalyses (p = 0.007). The last morphologic classification of AM corresponded to the first in all patients with grade II AM, but only in 74% of patients with grade I AM. The following conclusions were drawn. (1) Most AM of unknown etiology persists over several years irrespective of grade and morphology of erythrocyturia.(ABSTRACT TRUNCATED AT 250 WORDS)