Antibiotic associated diarrhea and Clostridium difficile associated diarrhea in the elderly

Antibiotic associated diarrhea (AAD) is a common complication when antibiotics are used and is frequent in the elderly. It has an impact on the length of hospital stay and increases the comorbidity. Together with the type of antibiotic that is given, the length of antibiotical treatment and the combination of antibiotics is more predictive for the evolution of diarrhea when compared to the total given dose. Mostly AAD is benign, but an infection with C. difficile should always be excluded. C. difficile-enterocolitis is frequent among residents in nursing homes and in hospitalised patients. The clinical presentation varies from asymptomatic colonisation tot severe debilitating disease. A rapid diagnosis can be performed by detection of C. difficile toxin by an enzyme-linked immunoassay. Oral metronidazole and oral vancomycine are equally effective in the therapy. In relapsing infection an extended tapering regimen is sometimes necessary.     

Actin associated with plasmodesmata

Summary We have used several methods to localise actin associated with plasmodesmata. In meristematic plant material fixed in 0.1% glutaraldehyde/1% paraformaldehyde and embedded in LR White resin, actin was localised (in TEM using 5 nm gold-labelled secondary antibody to C₄ anti-actin primary antibody) in the neck region by the plasma membrane and endoplasmic reticulum, and also down the length of the plasmodesma, deep in the cell wall. When the chemical fixation was replaced by rapid freezing in liquid propane (without cryoprotectants) and substitution in acetone, the plasmodesmata were labelled in similar positions, but with less background label on sections. While only 8–20% of plasmodesmata were labelled, the label was 10 to 100 fold denser over plasmodesmata than over the surrounding wall indicating specific association with plasmodesmata. We presume the apparent extracellular location of some label was due to the size of the antibodies between the site of attachment and the observed position of the gold particle. Gold label was found in similar locations in material fixed in 3% paraformaldehyde, infiltrated with sucrose, frozen, sectioned (10–12 m thick), then labelled with antibodies before resin embedding. Furthermore, cell walls in epidermal peels stained with rhodamine-phalloidin showed localised patches of fluorescence, presumably at the site of plasmodesmata (or primary pit-fields), which were connected on either side to fluorescent strands of actin in the cytoplasm. Suspension cultured cells ofNicotiana plumbaginifolia similarly stained showed very faint, narrow fluorescent strands crossing the walls of sister cells, which may indicate actin associated with individual plasmodesmata, shown in TEM to be sparsely distributed in these walls. In addition, the neck regions of cytochalasin-treated plasmodesmata were greatly enlarged and lacked the normal extracellular ring of particles. We propose that actin associated with plasmodesmata stabilizes the neck region and possibly also the cytoplasmic sleeve, and may be actively involved in regulating cell-to-cell transport.Abbreviations BSA bovine serum albumin - EDTA ethylenediaminetetraacetic acid - EGTA ethyleneglycol bis-(-aminoethyl ether)-N,N,N,N-tetraacetic acid - PAGE polyacrylamide gel electrophoresis - PBS phosphate buffered saline - Pipes piperazine-N,N-bis(2-ethanesulphonic acid) - Mes 2(N-morpholino)ethanesulfonic acid - SDS sodium dodecyl sulphate - Tris tris-(hydroxymethyl)aminomethane     

Friedelin and associated triterpenoids

The literature is reviewed for the natural occurrence of the pentacyclic triterpenes, friedelin and the epimeric 3-friedelanols. A summary of the literature relating to the structure elucidation, physical properties, synthesis and biosynthesis of these friedelane derivatives is presented. Compounds possessing the same carbon skeleton (D: A-friedelooleanane) and occurring with at least one of the above friedelane derivatives are also tabulated.     

Yeasts associated with Manteca

Manteca is a traditional milk product of southern Italy produced from whey deriving from Caciocavallo Podolico cheese-making. This study was undertaken to obtain more information about the microbiological properties of this product and particularly about the presence, metabolic activities, and technological significance of the different yeast species naturally occurring in Manteca. High numbers of yeasts were counted after 7 days ripening (10(4)-10(5) cfu g(-1)) and then decreased to 10(2) at the end. A total of 179 isolates were identified and studied for their phenotypic and genotypic characteristics. The most frequently encountered species were Trichosporon asahii (45), Candida parapsilosis (33), Rhodotorula mucilaginosa (32), Candida inconspicua (29). Some of these yeasts showed lipolytic activity (32 strains) and proteolytic activity (29 strains), NaCl resistance up to 10% and growth up to 45 degrees C (42 strains). Biogenic amines were formed by proteolytic strains, in particular phenylethylamine, putrescine and spermidine. Spermidine was produced by all the yeasts tested in this work, but only Trichosporon produced a great quantity of this compound. Histamine was not detectable. Caseinolytic activity was common to almost all strains, corresponding to the ability to efficiently split off amino-terminal amino acids. The highest and most constant activity expressed by all species was X-prolyl-dipeptidyl aminopeptidase. The findings suggest that the presence of yeasts may play a significant role in justifying interactions with lactic acid bacteria, and consequently with their metabolic activity in the definition of the peculiar characteristics of Manteca cheese.     

Recall of associated memories

A mechanism of serial association in the brain is discussed. The passage from one state to another is assumed to be effected by a control operated by the thalamus on the cortex. Memory failure mechanisms are discussed, such as insufficient imprint, as well as Freudian failure phenomena.     

The amylase activity associated with Cellulomonas flavigena is cell associated and inducible

Summary Analysis of the amylase activity associated withCellulomonas flavigena showed that it was a cell associated activity that could be released upon sonication, it was active against amylopectin and starch but showed no activity against pullulan and only slight activity against amylose. The enzyme was also found to have liquifying activity and to be inducible.     

AIDS and associated malignancies

INTRODUCTION It has been over twenty years since the onset of the AIDS epidemic, and in spite of the tremendous progress made towards the understanding of the disease, the virus that causes the disease and the development of highly ef- fective anti-retrov…     

AIDS and associated malignancies

AIDS associated malignancies (ARL) is a major complication associated with AIDS patients upon immunosuppression.Chronically immunocompromised patients have a markedly increased risk of developing lymphoproliferative disease. In the era of potent antiretrovirals therapy (ARV), the malignant complications due to HIV- 1 infection have decreased in developed nations where ARV is administered, but still poses a major problem in developing countries where HIV- 1incidence is high and ARV is still not yet widely available. Even in ARV treated individuals there is a concern that the prolonged survival of many HIV- 1 carriers is likely to eventually result in an increased number of malignancies diagnosed.Malignancies that were found to have high incidence in HIV-infected individuals are Kaposi‘s sarcoma (KS), Hodgkin‘s disease (HD) and non-Hodgkin‘s lymphoma (NHL). The incidence of NHL has increased nearly 200 fold in HIV-positive patients, and accounts for a greater percentage of AIDS defining illness in the US and Europe since the advent of HAART therapy. These AIDS related lymphomas are distinct from their counterparts seen in HIV- 1 seronegative patients.For example nearly half of all cases of ARL are associated with the presence of a gamma herpesvirus, Epstein Barr virus (EBV) or human herpesvirus-8 (HHV-8)/Kaposi‘s sarcoma associated herpesvirus (KSHV). The pathogenesis of ARLs is complex. B-cell proliferation driven by chronic antigenemia resulting in the induction of polyclonal and ultimately monoclonal lymphoproliferation may occur in the setting of severe immunosuppression.     

AIDS and associated malignancies

AIDS associated malignancies (ARL) is a major complication associated with AIDS patients upon immunosuppression. Chronically immunocompromised patients have a markedly increased risk of developing lymphoproliferative disease. In the era of potent antiretrovirals therapy (ARV), the malignant complications due to HIV-1 infection have decreased in developed nations where ARV is administered, but still poses a major problem in developing countries where HIV-1 incidence is high and ARV is still not yet widely available. Even in ARV treated individuals there is a concern that the prolonged survival of many HIV-1 carriers is likely to eventually result in an increased number of malignancies diagnosed. Malignancies that were found to have high incidence in HIV-infected individuals are Kaposi's sarcoma (KS), Hodgkin's disease (HD) and non-Hodgkin's lymphoma (NHL). The incidence of NHL has increased nearly 200 fold in HIV-positive patients, and accounts for a greater percentage of AIDS defining illness in the US and Europe since the advent of HAART therapy. These AIDS related lymphomas are distinct from their counterparts seen in HIV-1 seronegative patients. For example nearly half of all cases of ARL are associated with the presence of a gamma herpesvirus, Epstein Barr virus (EBV) or human herpesvirus-8 (HHV-8)/ Kaposi's sarcoma associated herpesvirus (KSHV). The pathogenesis of ARLs is complex. B-cell proliferation driven by chronic antigenemia resulting in the induction of polyclonal and ultimately monoclonal lymphoproliferation may occur in the setting of severe immunosuppression.     

AIDS and associated malignancies

AIDS associated malignancies （ARL） is a major complication associated with AIDS patients upon irnmunosuppression. Chronically immunocompromised patients have a markedly increased risk of developing lymphoproliferative disease. In the era of potent antiretrovirals therapy （ARV）, the malignant complications due to HIV-1 infection have decreased in developed nations where ARV is administered, but still poses a major problem in developing countries where HIV-1 incidence is high and ARV is still not yet widely available. Even in ARV treated individuals there is a concern that the prolonged survival of many HIV-1 carriers is likely to eventually result in an increased number of malignancies diagnosed. Malignancies that were found to have high incidence in HIV-infected individuals are Kaposi＇s sarcoma （KS）, Hodgkin＇s disease （HD） and non-Hodgkin＇s lymphoma （NHL）. The incidence of NHL has increased nearly 200 fold in HIV-positive patients, and accounts for a greater percentage of AIDS defining illness in the US and Europe since the advent of HAART therapy. These AIDS related lymphomas are distinct from their counterparts seen in HIV- 1 seronegative patients. For example nearly haft of all cases of ARL are associated with the presence of a gamma herpesvirus, Epstein Barr virus （EBV） or human herpesvirus-8 （HHV-8）/Kaposi＇s sarcoma associated herpesvirus （KSHV）. The pathogenesis of ARLs is complex. B-cell proliferation driven by chronic antigenemia resulting in the induction of polyclonal and ultimately monoclonal lymphoproliferation may occur in the setting of severe immunosuppression.     

Prototheca associated with banana

Prototheca stagnora was found to be a habitant of older harvested banana (Musa sapientum) and plantain (M. paradisiaca) stumps while P. wickerhamii colonized fresh Musa sp. stumps and flower bract water of Heliconia sp. While Prototheca sp. were known to habituate woody plants, this is the first evidence that herbaceous plants also serve as habitats.