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Investigation into the early hydration of Portland cement was performed by in situX-ray diffraction (XRD). Technical white cement was used for the XRD analysis on a D5000 diffractometer (Siemens). All diffraction patterns of the in situmeasurement which were recorded up to 22 h of hydration at defined temperatures were analyzed by Rietveld refinement. The resulting phase composition was transformed with respect to free water and C-S-H leading to the total composition of the cement paste. The hydration reactions can be observed by dissolution of clinker phases as well as by the formation of the hydrate phases ettringite and portlandite. With increasing temperatures the reactions proceed faster. The formation of ettringite is directly influenced by the rate of dissolution of anhydrite and tricalcium aluminate (C3A). The beginning of the main period of hydration is marked by the start of portlandite formation. The experiments point out that a quantitative phase analysis of the cement hydration is feasible with standard laboratory diffractometers.

Both mycophenolate mofetil (MMF) and azathioprine (AZA) are immunosuppressive drugs that inhibit purine synthesis. In theory, MMF selectively inhibits lymphocyte proliferation, while AZA has well-known effects on red blood cells and thrombocytes as well. In renal transplant recipients we replaced CsA therapy by MMF in an attempt to reduce the immunosuppressive load 1 year after kidney transplantation. During this study we observed the effect of MMF on haematological parameters such as haemoglobin (Hb), leukocytes, and thrombocytes.

Triple drug treatment consisting of mycophenolate mofetil (MMF), in a standard dose of 2 g daily, combined with cyclosporine (CsA) and prednisone, has become the standard immunosuppressive regimen after kidney transplantation in many centers. The need for therapeutic drug monitoring of mycophenolic acid (MPA) has not yet been established. Several drug interactions with MMF are known. We investigated the influence of CsA withdrawal on MPA trough levels in renal transplant patients.

24 heart transplant recipients were treated with OKT3 together with azathioprine for 7 days as a rejection prophylaxis. The plasma OKT3 concentration ranged from 280 to 1600 ng/ml. During treatment the T cells in peripheral blood disappeared but returned modulated without TcR‐α/β‐chains and with low CD3 expression. Antimurine antibodies were induced and median IgG antimurine antibody concentrations increased from 9.6 mg/l pretransplant to 52.1 mg/l as measured by ELISA. In 13 out of 24 patients, anti‐idiotypic antibodies were present at a level that caused over 50% inhibition of OKT3 binding to T cells. The extent of inhibition was positively correlated with the increase in IgG antimurine antibody levels, both in relative (> 3 times pre‐transplant level, p < 0.05) and in absolute terms (more than 50 mg/l, p < 0.001). In 9 patients, who received two prophylactic courses of OKT3, we found a decrease in anti‐OKT3 antibody levels after the second course of OKT3 which can be caused by the additional cyclosporin A (CsA) immune suppression. The second course also resulted in a rapid depletion of circulating functional T cells despite the presence of anti‐OKT3 antibodies generated after the first course.

Abstract:  Stereoselectivity in the oxidation of ferrocenyl sulphides with several species of microorganisms such as Corynebacterium equi was reversed between (methylthiomethyl)ferrocene and (t-butylthiomethyl)ferrocene, indicating that the size of the side chain could control the stereochemical course of the biooxidation. The size seems to be effective within some limit, because the more bulky compound, (phenylthiomethyl)ferrocene, was a poor substrate. On the other hand, the microbial oxidation of (methylthiomethyl)ruthenocene and -osmocene with Mortierella isabellina and that of (t-butylthiomethyl)ruthenocene and -osmocene with C. equi gave levorotatory sulphoxides (85–97% e.e.), which were all found to have R absolute configuration. These stereoselectivities were the same as those for the corresponding ferrocenyl sulphides. Thus, the central atom of the metallocenic sulphides seems not to affect the stereoselectivity in the biooxidation. The microbial oxidation is a useful method to prepare several kinds of chiral metallocenic sulphoxides with high optical purity.

In order to elucidate the reaction scheme of the oscillatory malonic acid-KBrO3system in sulphuric acid the products extracted from the reaction system by ether are analysed by gas chromatography and mass spectrometry. After 2 hours reaction time implying approx. 80 to 100 cycles malonic acid, monobromomalonic acid and dibromoacetic acid are identified in a relative ratio of about 1.0, 0.14 and 0.023.

Summary A multidimensional concept of diagnosis and treatment of mental disorders is presented. Major contributions to basic research come from pharmacological experiments. Clinical outcome in treatment of endogenous depression can be assessed by rating scales and psychophysiological tests and correlated with the serum level of the drug. In the case of maprotiline there seems to be a correlation between serum level and clinical outcome.

Sixteen kidney transplant recipients received the IgG2a anti-CD3 monoclonal antibody OKT3 and azathioprine as rejection prophylaxis during the first two postoperative weeks. Concomitant immunosuppression consisted of low dose steroids while cyclosporine A therapy was instituted on day 12. Side effects included fever, bronchospasm, hypotension and diarrhoea. OKT3 caused T cell modulation resulting in CD3 dim +, CD4+ or CD8+, CD5+, WT31− and 11F2−cells. Anti-OKT3 antibodies were found in approximately 50% of the patients. The protocol induced a 100% patient and graft survival and a 81% actuarial freedom of rejection at 18 months. It prevented CsA associated nephrotoxicity in the direct postoperative phase.

We studied the effects of a single intravenous injection of rabbit ATG (RIVM, Bilthoven, The Netherlands) in a dose of 8 mg/kg body weight administered 6 h after kidney transplantation on graft survival, rejection incidence, T-cell subsets, and cost-effectiveness. A total of 58 (37 male/21 female) consecutive renal allograft recipients were entered in this trial. Treatment results were compared with 56 patients treated with intravenous cyclosporin (CyA). In all patients concomitant medication consisted of steroids and azathioprine, followed by oral CyA. Following rabbit ATG, T cells (WT31) quickly disappeared from the peripheral blood and a return to greater than 100/mm3 was observed at a median of 7 (range 3–21) days. Graft survival was the same in both groups, as was the incidence of primary nonfunction. The rate of acute rejection was significantly lower in the rabbit ATG-treated patients (12% vs 50%). We conclude that a single shot of rabbit ATG is an attractive, easy, and cost-effective induction scheme with a low incidence of delayed graft function and acute rejection episodes. A relatively high incidence of vascular thrombosis of the graft, however, warrants further study before this treatment regimen can be generally applied.

In a double-blind, randomized, placebo-controlled trial, BT563, a murine IgGt anti-IL-2R antibody, was given as a rejection prophylaxis after kidney transplantation. Drug-related side effects were not observed. During the 10-day course of BT563, no rejections (0/27) were found, whereas a rejection episode occurred in 7 patients (7/29) (P=0.01) during placebo treatment. Within the first 4 postoperative weeks, freedom from rejection in the BT563 group and in the placebo group was 96 vs. 76 (P=0.05). Due to rejection in the placebo group, 2 grafts were lost. At 3 months, an overall rejection incidence in the BT563 and placebo group was found of 3/27 (11) vs. 8/29 (28) patients (P=0.18). Infectious complications were distributed equally between the 2 groups. CMV disease, found in 3 placebo-treated patients, occurred after rejection treatment (2/3). Within the BT563 group, 1 patient lost his graft due to renal artery thrombosis, 2 grafts were lost as a result of technical failure, and 2 patients had a squamous cell carcinoma that could be treated curatively. We conclude that the use of the anti-IL-2R mAb BT563 effectively prevents rejection after kidney transplantation without increasing infectious complications.

Abstract The TNF-α system is thought to play a central role in the reduced immunity of haemodialysis patients. The imbalance between the high levels of soluble TNF receptors R 1 and R 2 and the low levels of immunoactive TNF-α results in an increased TNF-α buffering capacity leading to reduced immune responses. Apart from impaired renal clearance of the receptors, inefficient TNF-α production as a result of the uraemia may also contribute to the imbalance between this cytokine and its receptors. In patients receiving a living-related kidney transplant, renal function is nearly normalized in a very short period. This restoration of renal function may result in a state of better immunocompetence, either as a result of improved clearance of the receptors or as a result of reversal of the uraemic state. To differentiate between these two possibilities, we measured TNF-α protein, mRNA and the soluble TNF receptors R 1 and R 2 before and after successful renal transplantation. TNF-α mRNA was not affected by transplantation, indicating constant TNF-α production. The imbalance in the TNF-α system was markedly improved after transplantation, although normal values of the soluble receptors were not reached. One year after transplantation in stable kidney transplant recipients there was still an imbalance in the TNF-α system caused by persistently elevated levels of the soluble TNF-receptors. These results suggest that even after successful kidney transplantation the TNF-α system remains activated. However, despite immunosuppressive therapy, recipients of a living-related kidney do have a better balanced TNF-α system compared to haemodialysis patients.

A simple and reliable method for the determination of piracetam in serum and brain homogenates is presented.

Objectives Biochemical markers for Alzheimer's disease would be of great value, especially to help in diagnosis early in the course of the disease. A pronounced increase in CSF tau protein (CSF-tau) is found in most patients with Alzheimer's disease. However, the specificity has to be further studied, as an increase in CSF-tau has also been found in other dementias, especially in vascular dementia. As most previous CSF studies have been based on selected inpatients, it was considered of special interest to examine the diagnostic potential of CSF-tau in a community population based sample of consecutive patients with dementia. Such patient material has been examined at the Pitea River Valley Hospital in Northern Sweden since 1986, and includes all those with memory disturbances in the community. The aim was also to study if an increase in CSF-tau is found early in the disease process, and whether CSF-tau changes during the progression of disease. Methods Participants: Community population based sample of 75 demented patients (43 with Alzheimer's disease, 21 with vascular dementia, and 11 with mixed Alzheimer's disease/vascular dementia), 18 healthy subjects, and 18 neurological controls. A follow up investigation (including analysis of a new CSF sample) was performed in all patients after about one year. Main outcome measures Concentrations of total (both normal tau and PHF-tau) tau in CSF, clinical measures (duration and severity of dementia), and apoE polymorphism. Results CSF-tau was markedly increased in Alzheimer's disease, 41/43 (95%) patients had values above the cut off level (mean+2 SD) in controls (306 pg/ml). High CSF-tau concentrations were also found in most patients with vascular dementia, preferentially in patients with vascular dementia without progressive leukoaraiosis on CT, whereas patients with vascular dementia with progressive leukoaraiosis had normal CSF-tau. Concentrations of CSF-tau were stable at one year follow up in both patients with Alzheimer's disease and patients with vascular dementia, and there was no correlation between CSF-tau and either duration or severity of dementia. Conclusions The findings confirm the high sensitivity of CSF-tau for the diagnosis of Alzheimer's disease, but high CSF-tau was also found in vascular dementia, resulting in a lower specificity. However, high CSF-tau is preferentially found in patients with vascular dementia without progressive leukoaraiosis, which may constitute a group with concomitant Alzheimer's disease pathology. High CSF-tau may be present during the whole course of the disease in Alzheimer's disease. Possibly, therefore, the same high CSF-tau concentrations may be present before the onset of clinical dementia. Follow up studies on such patients will tell whether analysis of CSF-tau is useful as a biochemical marker for early Alzheimer's disease.

The first-passage problem is considered for the process [image omitted]  where V(s) is an Ornstein-Uhlenbeck process with an additive constant term μ friction parameter β, and variance σ2 starting from V(O)=μ+μ Global explicit analytic approximations to the first-passage density are derived for the case of a one-sided fixed barrier at distance x from X (0). By a series of simulations the quality of these approximations is studied for varies χ,ν,β,μ,σ2. We also consider an application to stochastic models for particle sedimentation in fluids where the first-passage problem of an integrated Ornstein-Uhlenbeck process naturally arises.

The γ radiolysis of carbon tetrachloride at 77 K results in the formation of free radicals which are stable at 185 K and have been identified as ĊCl3. These radicals trapped in crystallites of CCl4 or at 'boundaries' give very different E.S.R. spectra. Their a13C coupling constants are practically identical (117 G et 114 G). The structure of ĊCl3 radicals has been determined: it is nonplanar and the [image omitted] angle has a value of 116°. The action of O2 on the ĊCl3 radicals leads to the CCl3[image omitted]2 peroxide radicals whose a13C coupling at 200 K is 6·15 G.Après irradiation γ à 77 K du tétrachlorure de carbone, le seul radical stable à 185 K est le radical ĊCl3. Le radical ĊCl3, suivant qu'il est piégé au sein des cristallites de CCl4 ou aux joints de grains, donne un spectre R.P.E. très différent.Pour les deux types de radicaux, les constantes de couplage a13C sont voisines (117 G et 114 G). On peut ainsi en déduire que le radical CCl3 est non plan avec une valeur de 116° pour l'angle [image omitted]. Par action de l'oxygène sur le radical ĊCl3, on a observé à 200 K le radical CCl3[image omitted]2 dont la constante de couplage a13C est 6,15 G.