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Subsequent Disappearance (subsequent + disappearance)

Distribution by Scientific Domains

Medical Sciences	50%

Selected Abstracts

Could rising aquatic carbon dioxide concentrations favour the invasion of elodeids in isoetid-dominated softwater lakes?

FRESHWATER BIOLOGY, Issue 9 2009
P. SPIERENBURG
Summary 1. During the past century, isoetid vegetation types in softwater lakes have often been invaded by faster-growing elodeids. In these C-limited systems, this may be related to rising aquatic CO2 levels. 2. In a laboratory experiment we tested the growth response of two elodeid species, Myriophyllum alterniflorum and Callitriche hamulata, at four different CO2 levels, ranging from 20 to 230 ,mol L,1. In addition, we tested the effect of the nutrient status of the sediment on the growth of C. hamulata at the different CO2 levels. 3. Shoot and root growth increased with rising CO2 availability. Irrespective of sediment type, growth was minimal to negative at the lowest CO2 treatment level, while becoming positive at CO2 levels around 40,50 ,mol L,1. Substantial growth was only obtained when the macrophytes were growing on mesotrophic sediments. The plants reached close to maximal growth at CO2 levels of c. 100 ,mol L,1. 4. Within this experiment, the growth of C. hamulata at CO2 levels above 90 ,mol L,1 may have been limited by N and P availability in both sediment types. The growth rate of M. alterniflorum did not seem to be limited by N and P availability, most likely due to its much higher relative root production. 5. The experimental results show that neither M. alterniflorum nor C. hamulata is able to invade isoetid-dominated softwater lakes at very low aquatic CO2 concentrations. However, if the sediments contain enough nutrients, a rise in aquatic CO2 could allow the invasion of elodeid species leading to the subsequent disappearance of slow-growing isoetids. [source]

Idiopathic myelofibrosis with extramedullary haemopoiesis involving the urinary bladder in a Chinese lady

INTERNATIONAL JOURNAL OF LABORATORY HEMATOLOGY, Issue 1 2002
Y. K. MAK
Extramedullary haemopoiesis (EMH) associated with idiopathic myelofibrosis most commonly involves the reticuloendothelial organs, such as the spleen and liver, although ectopic haemopoietic tissue has also been described rarely in the lymph nodes, skin, gastrointestinal tract, pleura, peritoneum, central nervous system, and genital and urinary tracts. We report on a 54-year-old Chinese lady with a long history of idiopathic myelofibrosis who presented with gross haematuria and left hydronephrosis due to EMH in the bladder trigone. Cystoscopic examination revealed a sessile necrotic papillary growth at the trigone, obstructing the left ureteric orifice. Transurethral resection of the bladder tumour was performed, and microscopic examination of the tumour chips demonstrated atypical megakaryocytes, immature granulocytes and normoblasts, confirming the presence of EMH. The residual bladder tumour responded well to low dose radiotherapy, with subsequent disappearance of haematuria and normalization of ultrasonogram findings. [source]

Raman spectroscopic signature of life in a living yeast cell

JOURNAL OF RAMAN SPECTROSCOPY, Issue 7 2004
Yu-San Huang
Abstract We have discovered a Raman spectroscopic signature that sharply reflects the metabolic activity of a mitochondrion in a living yeast cell. Raman mapping experiments on a GFP-labeled yeast cell showed that this signature originated exclusively from mitochondria. Addition of KCN caused a rapid decrease and subsequent disappearance of the signature followed by gradual changes of the phospholipid Raman bands, indicating that respiration was first inhibited by KCN and then lowered metabolic activity gradually deteriorated the double-membrane structure of a mitochondrion. We can now monitor the life and death of a single cell by time- and space-resolved Raman spectroscopy. Copyright © 2004 John Wiley & Sons, Ltd. [source]

Transient pancytopenia preceding acute lymphoblastic leukaemia (pre-ALL) precipitated by parvovirus B19

BRITISH JOURNAL OF HAEMATOLOGY, Issue 4 2001
Erik D. Heegaard
A preleukaemic phase, typified by pancytopenia and bone marrow (BM) hypoplasia, is an uncommon but well-documented prelude to acute lymphoblastic leukaemia (pre-ALL) in children. Parvovirus B19 (B19) exhibits a marked tropism to human BM and replicates only in erythroid progenitor cells acting as a confounding, but treatable agent in immunocompromised patients. We present the first case of B19-associated pre-ALL characterized by severe and recurring transient pancytopenia in a child who developed ALL 5 months later. The advent of B19-specific IgG at the time of infection and the subsequent disappearance 1·5 years later has not previously been described. In this patient the observed cytopenias were probably the result of B19 acting in concert with the failing BM and B19 is possibly one of several factors capable of triggering the onset of pre-ALL. [source]