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Expression of microRNAs can affect age of tumor onset and prognosis of cancer patients. However, nothing is known about the effects of microRNAs on altered age of cancer onset and disease-specific survival of soft-tissue sarcoma (STS) patients. The levels of miR-210, also known as hypoxia-regulated microRNA, were analyzed by quantitative real-time (RT)-PCR in the tumors of 78 STS patients. The patients were stratified according to their microRNA levels with low, intermediate and high expression levels and the association of microRNA expression and patients' survival was analyzed using multivariate Cox's regression hazard analyses. A significant correlation between an intermediate miR-210 expression and disease-specific death of STS patients [relative risk (RR) = 3.19; p = 0.018] was observed compared with patients with high expression levels in their tumors. Interestingly, the association between an intermediate expression of miR-210 and a poor prognosis was only significant in female STS patients (RR = 11.28; p = 0.010), but not observed in male individuals. Furthermore, the expression of miR-210 showed a significant association with the age of tumor onset in a gender-specific manner. Specifically, male patients with an intermediate expression of miR-210 associated with a 9.6-year later age of tumor onset ( p = 0.017) compared with males with a low expression of miR-210 in their tumors. However, no significant differences in the female patients were observed. This study provides the first evidence of a correlation of expression levels of a single microRNA ( miR-210) with the prognosis and age of tumor onset in a gender-specific manner in STS patients. [ABSTRACT FROM AUTHOR]

A 40-year-old man with multivisceral allograft developed acutely right-sided numbness 9 months after transplantation. Cranial magnetic resonance imaging (MRI) showed a small left parietal lesion, and cerebrospinal fluid analysis was unremarkable. Stereotactic brain biopsy was non-diagnostic. The patient continued to deteriorate, developed cerebral edema and died at 13 days after the onset of symptoms. Unexpectedly, autopsy demonstrated acanthamebic encephalitis. This case highlights diagnostic difficulties encountered with amebic encephalitis and expands the spectrum of opportunistic central nervous system (CNS) infections in solid and visceral organ transplant recipients. [ABSTRACT FROM AUTHOR]

A 37-year-old small bowel transplant recipient with a history of urolithiasis was admitted for dysuria after passing a urinary stone. His laboratory evaluation showed increased blood urea nitrogen and creatinine. Urinalysis showed increased white blood cells and positive leukocyte esterase. A computed tomography scan revealed signs of urinary tract obstruction and prostatic enlargement. He failed to respond initially to empiric antibiotic treatment with ciprofloxacin and ampicillin sulbactam while waiting for culture results. The pathogen recovered from both urine and blood culture was subsequently identified as Nocardia asteroides complex. The isolate was sensitive to ceftriaxone and sulfa but resistant to ciprofloxacin. The patient improved on ceftriaxone and trimethoprim-sulfamethoxazole and completed a 6-month course without any relapse. Nocardia prostatitis is an uncommon infection and must be treated with a long course of antibiotics guided by susceptibility testing. [ABSTRACT FROM AUTHOR]

Following the earlier reported detection of root nodules on a species of Colletia growing in the Glasgow Botanic Gardens, the authors' enquiries have revealed that Colletia species are nodulated in some other botanic gardens, both in Europe and elsewhere. Cytological study of the nodules under the electron microscope shows that the endophyte is a procaryotic, actinomycete-like organism consisting of septate, branching hyphae which are 0.37 to 0.53 μm in diameter and form terminal spherical vesicles 2.0 to 2.5 μm in diameter. The vesicles are internally sub-divided and lie peripherally within the host cell. The endophyte is enclosed within a thin layer (or capsule) of material which judging by previous studies of other non-legume nodules consists of carbohydrate-related substances laid down by the host cytoplasm. Data from long-term growth trials and acetylene assays show that Colletia nodules are nitrogen-fixing and capable of satisfying the nitrogen-needs of the host plant. Of the five genera of the Rhamnaceae that have so far been found to be nodule-bearing, four (namely Colletia, Discaria, Trevoa and Talguenea) are in the tribe Colletieae, while the fifth genus (Ceanothus) is placed elsewhere in the family by taxonomists. A very similar situation exists in the Rosaceae as regards the distribution of nodulating genera and species. It is concluded that in these families the habit of symbiosis with a nitrogen-fixing actinomycete probably arose, in some instances, prior to the establishment of now-existing genera, but in others at a later stage. This conclusion is consistent with the belief that nodule symbioses were initiated in an earlier era when plants in general were subject to nitrogen stress. [ABSTRACT FROM AUTHOR]

The acetylene assay was used to find how soon nitrogenase activity could be detected in young, nodulating alder plants. Samples taken at intervals initially of 2-3 days were assayed, starting as soon as external signs of nodulation were seen, and continuing for a further 33 days. Squash preparations made from the nodules of the assayed plants were examined microscopically to detect whether there was any relation between nitrogenase activity and the stage of differentiation of the nodule endophyte. No nitrogenase activity was detected on the first two assay occasions, on which the endophyte was confined to the hyphal stage in all the nodules present. Activity was detected on the subsequent occasions, its onset coinciding with the production of vesicles by the endophyte. Activity rose as the vesicles became more abundant, and in agreement with the limited previous evidence it was concluded that the vesicles, but not the hyphae, are nitrogen- fixing. The third type of structure produced by the alder endophyte, namely the bacteroid stage, was not detected in the young nodules studied here. The onset of nitrogenase activity in the nodules preceded by 16 days the increased greening of the leaves signifying the arrival in the shoot of products of nitrogen fixation. Ethylene production per plant increased in exponential manner over the period of the experiment, while ethylene production per unit weight of nodule tissue rose ten-fold. [ABSTRACT FROM AUTHOR]

By means of growth experiments and [sup15]N tests on whole plants and their parts, it is shown that the root nodules present on Myrica cordifolia and M. pilulifera fix atmospheric nitrogen to an extent which suffices to sustain good growth of the plants in a rooting medium free of combined nitrogen. Thus the nodules have the same properties and physiological significance as the nodules of M. gale and M. cerifera. The possession of this internal source of combined nitrogen doubtless explains in part the ability of M. cordifolia to flourish on sand dunes. [ABSTRACT FROM AUTHOR]

The article discusses the role of Dryas drummondii in vegetation development following ice recession at Glacier Bay, Alaska, giving special attention to its nitrogen fixation by root nodules. It highlights the importance of the study among students of the Pleistocence in interpreting vegetation change since the retreat of the continental ice sheets. It also affirms that the location, Glacier Bay, is well suited for the study since the rate of recession of glaciers there is probably more rapid than anywhere else in the world.