Microbial community shifts induced by plastic and zinc as substitutes of tire abrasion.

Aquatic environments serve as a sink for anthropogenic discharges. A significant part of the discharge is tire wear, which is increasingly being released into the environment, causing environmental disasters due to their longevity and the large number of pollutants they contain. Main components of tires are plastic and zinc, which therefore can be used as substitutes for tire abrasion to study the effect on microbial life. We investigate environmentally realistic concentrations of plastic and zinc on a freshwater microeukaryotic community using high-throughput sequencing of the 18S V9 region over a 14-day exposure period. Apart from a generally unchanged diversity upon exposure to zinc and nanoplastics, a change in community structure due to zinc is evident, but not due to nanoplastics. Evidently, nanoplastic particles hardly affect the community, but zinc exposure results in drastic functional abundance shifts concerning the trophic mode. Phototrophic microorganisms were almost completely diminished initially, but photosynthesis recovered. However, the dominant taxa performing photosynthesis changed from bacillariophytes to chlorophytes. While phototrophic organisms are decreasing in the presence of zinc, the mixotrophic fraction initially benefitted and the heterotrophic fraction were benefitting throughout the exposure period. In contrast to lasting changes in taxon composition, the functional community composition is initially strongly imbalanced after application of zinc but returns to the original state.

Protistan and fungal diversity in soils and freshwater lakes are substantially different.

Freshwater and soil habitats hold rich microbial communities. Here we address commonalities and differences between both habitat types. While freshwater and soil habitats differ considerably in habitat characteristics organismic exchange may be high and microbial communities may even be inoculated by organisms from the respective other habitat. We analyze diversity pattern and the overlap of taxa of eukaryotic microbial communities in freshwater and soil based on Illumina HiSeq high-throughput sequencing of the amplicon V9 diversity. We analyzed corresponding freshwater and soil samples from 30 locations, i.e. samples from different lakes across Germany and soil samples from the respective catchment areas. Aside from principle differences in the community composition of soils and freshwater, in particular with respect to the relative contribution of fungi and algae, soil habitats have a higher richness. Nevertheless, community similarity between different soil sites is considerably lower as compared to the similarity between different freshwater sites. We show that the overlap of organisms co-occurring in freshwater and soil habitats is surprisingly low. Even though closely related taxa occur in both habitats distinct OTUs were mostly habitat-specific and most OTUs occur exclusively in either soil or freshwater. The distribution pattern of the few co-occurring lineages indicates that even most of these are presumably rather habitat-specific. Their presence in both habitat types seems to be based on a stochastic drift of particularly abundant but habitat-specific taxa rather than on established populations in both types of habitats.

Polymer-supported carbene complexes of palladium: well-defined, air-stable, recyclable catalysts for the Heck reaction

N-Heterocyclic dicarbene chelate complexes of formula [cis-CH2N(H)C=C(H)N(R)C2PdX2] (X = Br, I; R = (CH2)nOH; n = 2, 3) have been prepared and structurally characterized (for X= I, n = 2). The complexes were immobilized on a functionalized polystyrene support (Wang resin) through one of the oxygen centres. The complexes efficiently catalyze the Heck reaction of activated and non-activated arylbromides, are recyclable under aerobic conditions and exhibit hardly any leaching, which is in line with our theoretical investigations on ligand dissociation energies related to Pd0 and PdII centres.

Effect of green lentils on colonic function, nitrogen balance, and serum lipids in healthy human subjects.

Green lentils are an increasingly popular food, but their effects on human colonic function and serum lipids have been studied little. Nine healthy males aged 19-38 y consumed for 3-wk periods a controlled Western diet and the same diet supplemented with 130 g dry lentils/d [which contained 11.8 g non-starch polysaccharide (NSP)] incorporated into loaves, cakes, and soups. Protein was equilibrated with soy protein isolate and carbohydrate with soft drinks. Radioopaque markers were used to calculate mean transit time (MTT) and to correct fecal weight for infrequency of bowel movements. Feces were collected throughout the study and blood was taken on 2 d at the end of each period. Lentils increased fecal weight from 131 +/- 12 g/d (means +/- SEM) to 189 +/- 17.4 g/d (44.9%) (P < 0.005). MTT was unchanged: 46 +/- 6 h for the control diet and 43 +/- 4 h for the lentils (NS). Fecal nitrogen was increased to 2.49 +/- 0.08 g/d for lentils compared with 1.74 +/- 0.09 g/d for the control diet (P < 0.001) and urine nitrogen decreased to 15.31 +/- 0.52 g/d with the lentils compared with 15.90 +/- 0.51 g/d for the control diet (P < 0.05); nitrogen balance was unaffected. Serum lipids were unchanged by addition of lentils to the diet. Green lentils were effective in increasing fecal weight and can therefore make a valuable contribution to a healthy diet.

Intake of carbohydrate and its components--international comparisons, trends over time, and effects of changing to low-fat diets.

Carbohydrate constitutes the major source of dietary energy for all peoples of the world. However, it has been difficult to make accurate determinations of intakes of carbohydrate and its constituents because of lack of individual assessments in which carbohydrate components are included. For many countries, only food balance information is available and values for total carbohydrate are often derived by difference. Available information indicates that carbohydrate consumption decreased in many industrialized nations as prosperity led to an increased consumption of fat. Fat intakes have fallen over the past two decades and carbohydrate intakes have increased, but still do not approach the 60-70%contribution of carbohydrate to total energy in developing countries. A negative image for carbohydrate has led to a reluctance to accept it as a legitimate dietary component, particularly in North America. New evidence of the beneficial effects of starch in the diet indicates that increased consumption of carbohydrate, especially in the form of starch, should be promoted in Western countries.

[Quality assurance in legal social security evaluation--results and practical experiences with a quality assurance program]. / Qualitätssicherung in der Rentenbegutachtung--Ergebnisse und praktische Erfahrungen mit einem Qualitätssicherungsprogramm.

In the medical department of a statutory pension insurance bureau a quality assurance programme was established and tested. This programme is based on the "integrative assessment" of sociomedical expertises by means of a catalogue of 12 quality indicators. The results of a two-year period of working with this programme are discussed. The consequences with respect to qualifying procedures are also emphasised; these are based on individual and total data. Basing on the demands be made on the quality assurance programme--especially with regard to motivation, use, minimising costs, improving quality and acceptance--the handling of the procedure must be critically assessed. In addition, the author discusses the question as to which modifications would be more appropriate and promising.

Trends in individual fat consumption in the UK 1900-1985.

Mortality from coronary heart disease is decreasing in a number of Western countries, although the pattern of the decrease differs from country to country. In the UK the mortality rate from coronary heart disease has declined since 1979, whereas in the USA mortality from this disease began to fall in 1968 and has continued since that time. Of many factors suggested as reasons for the decline, diet has been implicated, particularly dietary fat intake. However, food balance information suggests little change in fat intake. A recent examination of all published studies from the USA where individual fat intake has been reported indicated that fat intake in that country has fallen steadily since the mid 1960s. The present study describes a similar compilation of all published studies from the UK giving individual fat intakes. Ninety-seven studies, representing information for 24,045 individuals, were used. Studies ranged in size from two to 3581 individuals and were drawn from all regions of the UK. Most studies used 7 d weighed intakes as the method of dietary assessment. Quadratic regression equations were applied to the fat intakes from all studies over time, with each study weighted by the number of individuals surveyed. Data were also divided into 10-year periods and weighted fat intakes for each decade were calculated. Data were expressed for all studies, then subdivided into males, females, children and the elderly. Comparisons between Scotland and the South-East of England were made. Results indicate that fat represented 30% or less of dietary energy in the UK until the 1930s, when it began to rise. This rise was curtailed by rationing during and after the Second World War, after which the rise continued, reaching a plateau of about 40% energy in the late 1950s, with little change until the late 1970s. Trends were similar in all age-groups, but less change has occurred recently in Scotland compared with South-East England. These results differ from the pattern in the USA and suggest that if greater changes in mortality from coronary heart disease are to be seen in the UK a greater reduction in dietary fat intake will have to occur.

[Clinical aspects, pathophysiology, therapy and expert evaluation of splenectomy]. / Klinik, Pathophysiologie, Therapie und Begutachtung des Milzverlustes.

Splenectomy increases on principle and for life the risk to die of a foudroyant postsplenectomy infection, the so called OPSI-syndrome. The main factors determining the frequency of the OPSI-syndrome are the age at time of operation and the indication for splenectomy. Postsplenectomy infection is mostly caused by pneumococci. In general the important pathophysiological factors are a lack of filtration capacity, a decreased opsonisation activity and a deficiency of early immunoglobulin production. The increased risk of children is probably caused by a physiologically reduced immune response and a cumulation of primary infections. In the foudroyant course of postsplenectomy infection therapy is mostly taken not in time, and mortality ranges between 50 and 80%. For this reason it is necessary to stress prophylaxis as: antibiotics, vaccination, autotransplantation and preserving surgery. The effectivity and application of these prophylactic measurements are clearly limited. Therefore it is very important to inform all patients and their parents about the low, but lifelong risk of infection following splenectomy in order to begin the antibiotic therapy as soon as possible even in cases of banal infections. In expert opinion about the loss of spleen the real situation of the splenectomized individual has to be regarded in making very precise analysis of the course of disease. This has to be done in considering the branch of insurance ordering the opinion (legal accident insurance, legal pensions insurance, social compensation law, private accident or life insurance). If infections or other illness often appear after splenectomy, these have to recognized as resulting impairment, provided that other causes have been excluded. In uncomplicated course it is not justified to suppose disability only by immanent risk.

Immunosuppressive effects of recombinant interferon-alpha during long-term treatment of cancer patients.

Interferons (IFN) are known to modulate immune responses in an either stimulatory or inhibitory manner. Most of the knowledge about immunomodulatory activities of IFN comes from investigations of IFN effects on cells in vitro. This study examines the influence which long-term treatment with recombinant interferon-alpha 2 exerts on immune functions in cancer patients. Serial in vitro immune function studies of peripheral blood mononuclear cells were done to determine parameters of B-cell and T-cell functions as well as natural killer (NK)-cell activity. The authors detected profound suppression of in vitro immunoglobulin synthesis and lymphocyte proliferation as well as depression of NK-cell activity during IFN treatment. All suppressed immune functions normalized on discontinuation of IFN therapy. The authors conclude from these observations that, apart from their beneficial effects, IFN produce substantial immunosuppression.

Abnormalities of B cell activation and immunoregulation in patients with chronic inflammatory liver diseases.

The immunoglobulin production capacities of peripheral blood lymphocytes obtained from patients with various chronic inflammatory liver diseases and from normal individuals were compared. Using a reverse hemolytic plaque assay, immunoglobulin-secreting cells (ISC) were counted immediately after isolation (immediate ISC) and again after 6-day, in vitro cultivation without stimulant (spontaneous ISC) or in the presence of pokeweed mitogen, PWM (PWM-induced ISC). An increased number of immediate ISC were observed in patients with chronic active hepatitis (CAH) of the autoimmune type (n = 7) or with CAH type B (n = 32), probably reflecting a defect of the in vivo suppressor cell system as previously demonstrated. In vitro preincubation of cells with 5 x 10(-8) M prednisolone reduced the increase in the number of immediate ISC in patients with CAH of the autoimmune type. On the other hand, lymphocytes obtained from patients with CAH-type NANB (n = 9) and with primary biliary cirrhosis (PBC) (n = 12) showed an impaired capacity to generate ISC upon stimulation with PWM. Spontaneous ISC from patients' lymphocytes were not significantly different from those of normal individuals. Using allogeneic co-cultures with lymphocytes from normal individuals and from patients with CAH NANB hepatitis or primary biliary cirrhosis, we observed no increase in suppressor cell activity. Therefore, the diminished responses to PWM are probably attributable to an alteration in the peripheral helper T-cell compartment.

Modulation of immune functions by long-term treatment with recombinant interferon-alpha 2 in a patient with hairy-cell leukemia.

Serial in vitro immune function studies of peripheral blood mononuclear cells (PBMC) were carried out during the long-term treatment with recombinant interferon-alpha 2 (IFN-alpha 2) in a patient with hairy-cell leukemia (HCL). Parameters of B- and T-cell functions as well as NK-cell activity were determined. Treatment with IFN-alpha 2 is associated with temporary and long-term depression of some immune functions, but can also normalize immune responses: in vitro-induced immunoglobulin synthesis, which was normal at diagnosis, was inhibited during the first weeks of IFN therapy but subsequently rose to normal levels. Lymphocyte proliferative responses to mitogens and antigens that were markedly reduced pretherapeutically were further depressed by IFN treatment but, with the exception of pokeweed mitogen (PWM)-induced responses, normalized completely by the 15th to 17th week of treatment. Cocultivation of PBMC with monocytes from normal individuals enhanced depressed lymphocyte proliferative responses. NK-cell activity, which was low at diagnosis, did not rise to the normal range during IFN treatment, but rapidly normalized when IFN therapy was stopped. A discussion is presented on the implications of the alteration of immune functions by treatment with IFN.

Chronic myelocytic leukemia as a second neoplasia in the course of chronic lymphocytic leukemia. Case report and review of the literature.

A patient with chronic lymphocytic leukemia developed Ph1-positive chronic myelocytic leukemia after a 6-yr course of CLL. Chemotherapy for CLL consisted of chlorambucil and steroids, later vincristine and bleomycin; after resistance to these agents, cyclophosphamide, vincristine and prednisolone were applied. When CML was diagnosed, we found two morphologically distinct populations of malignant cells in the bone marrow; the Ph1-chromosome was identified, and immunological surface marker studies also demonstrated two distinct malignant cell populations. Up to now, only five cases of CML have been reported following CLL and one case accompanying it. Three patients were treated with cytostatic drugs, one patient by total body irradiation and two patients received no therapy. At present, it is not clear whether the development of CML during CLL represents a therapy-induced complication or an increased susceptibility to second malignancies due to the leukemic process itself or possibly to immunological deficiencies in CLL. Since two patients received no treatment for CLL, previous therapy does not seem to be a prerequisite for the development of CML.

Coincident change of cellular function and phenotype in the course of a suppressor T cell acute lymphocytic leukaemia.

The phenotypic and functional characteristics of the leukaemic cells from one patient with T suppressor ALL were studied at the time of diagnosis and in relapse. At the time of diagnosis, the phenotype corresponded to the intermediate stage between the cortical and medullary phases of normal thymocyte differentiation with a high proportion of T8+ cells (E-R+, TdT+, C3bR-, T3-, T4-, T6+, T8++, T10+). Functionally, the cells did not respond to mitogens but mediated strong suppressor activity to allogeneic B-cells, as measured in a reversely haemolytic plaque test. Clinically, the patient exhibited the uncommon feature of hypogammaglobulinaemia. Induction therapy led to complete remission, which continued for 12 months. In the relapse, the phenotype remained essentially stable except for a dramatic decrease of the T8+ cell fraction and an increase of the T10+ cell fraction. Functionally, the suppressor activity was completely lost, indicating a close correlation between phenotype and functional activity in this leukaemic cell population.

Impaired B lymphocyte reactivity in patients after radiotherapy.

The effect of therapeutic irradiation upon B lymphocyte function was investigated in patients with various malignancies. The test system used was a reverse hemolytic plaque assay, which made it possible to study the activation and differentiation of B lymphocytes into immunoglobulin-secreting cells (ISC). Peripheral blood lymphocytes from normal individuals and patients before and after radiotherapy were stimulated in vitro with the polyclonal B cell activator pokeweed mitogen, and the number of ISC was estimated. B cell reactivity was markedly reduced in those patients who had received irradiation within the last six months. In patients in whom radiotherapy had been terminated more than 12 months before the lymphocytes were tested, B cell reactivity was comparable to that of patients prior to radiotherapy. By means of marker analyses, there was a reduction of B lymphocytes and T lymphocytes in the peripheral blood with a preponderance of T helper cells. Several mechanisms--e.g., reduced or defective B cell differentiation, altered regulatory T-helper or suppressor cell function or activation of suppressive monocytes--could be responsible for impaired B cell reactivity after radiotherapy.

Abnormalities of B-cell activation and immunoregulation in splenectomized patients.

Using a reverse hemolytic plaque assay as the effector system, we studied B-lymphocyte function in 12 patients after posttraumatic splenectomy, as well as in 25 normal individuals. The time interval between the splenectomy and the immunological studies varied between 2 days and 7 years. Compared to normal individuals, the splenectomized patients had markedly elevated numbers of spontaneous immunoglobulin-secreting cells (ISC) and severely decreased responses to the polyclonal activator pokeweed mitogen. A tendency towards normalization of these abnormalities, especially the high spontaneous ISC levels, could be observed during the time interval extending up to 7 years after splenectomy. In order to characterize the mechanism responsible for the altered immune response in splenectomized patients, co-culture experiments with unseparated and separated lymphocytes were performed. These revealed an impaired T-helper cell capacity as well as an intrinsic B-cell defect. Marker analyses with monoclonal antibodies revealed normal proportions with the exception of OKT 4 positive and B 1 positive cells that identify T-helper/inducer and peripheral B-cells respectively. We conclude that immune dysfunction in peripheral blood lymphocytes of splenectomized patients involves mainly the B-cell as well as the T-helper/inducer-cell population.

[Characterization of the leukemic cell population in a patient with T-ALL at disease beginning and in recurrence: parallel changes in phenotypic and functional behavior]. / Charakterisierung der leukämischen Zellpopulation bei einem Patienten mit T-ALL im Krankheitsbeginn und im Rezidiv: Parallele Veränderungen im phänotypischen und funktionellen Verhalten.

The phenotypic and functional characteristics of the leukemic cells from one patient with a suppressor T-ALL were studied. At the time of diagnosis a high proportion of OKT8 positive (suppressor/cytotoxic) cells were identified which mediated strong suppressor activity to the differentiation of allogenic B-cells. A complete remission of 12 months duration was achieved by chemotherapy. In the relapse the marker analysis showed a dramatic decrease of the OKT8 positive cell fraction. Functionally the suppressor activity was completely lost indicating a close correlation between phenotype and functional activity also in a leukemic cell population.

Chronic lymphocytic leukemia B-lymphocytes forming SRBC-rosettes not due to an anti-SRBC activity of monoclonal surface immunoglobulin.

A case of chronic lymphocytic leukemia is described in which large numbers of peripheral blood lymphocytes expressed immunoglobulin on their membrane and rosetted spontaneously with sheep red blood cells (SRBC) at 4 degrees C. They also showed weak staining with a heterologous antiserum against T-cells as well as with a monoclonal antibody (OKT11) with specificity for an epitope associated with the SRBC-receptor, but failed to react with other T-lineage-restricted monoclonal antibodies. The B-cell origin of the leukemic cells was documented by the presence of light-chain-restricted monoclonal surface immunoglobulin, reactivity with various monoclonal anti-B-cell reagents, presence of Ia-like antigens, their capability to synthesize intracytoplasmic immunoglobulin on exposure to phorbol ester TPA, their lack of response to T-cell mitogen PHA, and their inability to help or suppress the allogeneic B-cell response upon PWM stimulation. Extensive blocking studies with both specific antisera and Forsmann antigen-rich guinea pig kidney extracts, which did not prevent SRBC-rosetting, lend support to the hypothesis that SRBC-rosette formation in this case was not attributable to an anti-SRBC affinity of the surface immunoglobulin on the cells. This case will be discussed in relation to the recent finding of SRBC-rosette expression on some cultured chronic lymphocytic leukemia B-lymphocytes.