Biomedical subjects

A Waters

Publications and source records attributed to A Waters.

At least 19 recordsLinked to original sources

PubMed2001

Internal and external antecedents of binge eating episodes in a group of women with bulimia nervosa.

OBJECTIVE: This research examined the internal and external factors that predict whether a food craving develops into a binge in bulimia nervosa. METHOD: Fifteen bulimic women kept diary records of food cravings over the course of a week, noting their internal state, environmental triggers, and whether the craving developed into a binge. Eighty cravings were examined, of which approximately one half developed into binges. RESULTS: At the bivariate level, binge eating resulted from cravings more often if the women were alone, in the morning, and following eating the craved food. These factors interacted, so that binges were more likely if the women avoided a craved food in the morning, but not later in the day. CONCLUSIONS: These findings support a model of binge eating for which both internal states (craving, eating the craved food) and external factors (time of day, social circumstances) need to be taken into account. Relevant models of craving are discussed, along with their implications for clinical practice.

Adult↗

PubMed2000

HIV-specific CD8(+) T cells produce antiviral cytokines but are impaired in cytolytic function.

The use of peptide-human histocompatibility leukocyte antigen (HLA) class I tetrameric complexes to identify antigen-specific CD8(+) T cells has provided a major development in our understanding of their role in controlling viral infections. However, questions remain about the exact function of these cells, particularly in HIV infection. Virus-specific cytotoxic T lymphocytes exert much of their activity by secreting soluble factors such as cytokines and chemokines. We describe here a method that combines the use of tetramers and intracellular staining to examine the functional heterogeneity of antigen-specific CD8(+) T cells ex vivo. After stimulation by specific peptide antigen, secretion of interferon (IFN)-gamma, tumor necrosis factor (TNF)-alpha, macrophage inflammatory protein (MIP)-1beta, and perforin is analyzed by FACS((R)) within the tetramer-positive population in peripheral blood. Using this method, we have assessed the functional phenotype of HIV-specific CD8(+) T cells compared with cytomegalovirus (CMV)-specific CD8(+) T cells in HIV chronic infection. We show that the majority of circulating CD8(+) T cells specific for CMV and HIV antigens are functionally active with regards to the secretion of antiviral cytokines in response to antigen, although a subset of tetramer-staining cells was identified that secretes IFN-gamma and MIP-1beta but not TNF-alpha. However, a striking finding is that HIV-specific CD8(+) T cells express significantly lower levels of perforin than CMV-specific CD8(+) T cells. This lack of perforin is linked with persistent CD27 expression on HIV-specific cells, suggesting impaired maturation, and specific lysis ex vivo is lower for HIV-specific compared with CMV-specific cells from the same donor. Thus, HIV-specific CD8(+) T cells are impaired in cytolytic activity.

CD8-Positive T-Lymphocytes↗

PubMed2000

Does triacylglycerol biosynthesis require diacylglycerol acyltransferase (DAGAT)?

Microsomal membrane preparations from the developing seeds of sunflower (Helianthus annuus L.) catalyse the conversion of sn-glycerol-3-phosphate and acyl-CoA to triacylglycerol via phosphatidic acid and diacylglycerol. The formation of diacylglycerol from phosphatidic acid was Mg2+ dependent and in the presence of EDTA phosphatidic acid accumulated. This property was used to generate large quantities of endogenous radioactive phosphatidic acid in the membranes. On addition of Mg2+ the phosphatidic acid was used in triacylglycerol formation. Acyl-CoA had little effect on the label which accumulated in triacylglycerol from phosphatidic acid. Diacylglycerol acyltransferase, therefore, may not play a major role in oil formation as originally envisaged and other enzymes, including diacylglycerol:diacylglycerol transacylase [Stobart, Mancha, Lenman, Dahlqvist and Stymne (1997) Planta 203, 58-66] may have important biosynthetic functions.

Acyl Coenzyme A↗

PubMed1999

Massive plexiform neurofibroma of the sympathetic trunk.

A case report of a massive plexiform neurofibroma of the sympathetic trunk is reported. Symptoms included dysphagia, shortness of breath and paraesthesia of the right hand. The nerve of origin and extent of the tumour were unusual. The tumour mass partially filled the right hemithorax, surrounded the right brachial plexus, extended to the base of skull and invaded the cervical vertebrae threatening to compromise the spinal cord. Surgical resection required combined cardiothoracic, neurosurgical and plastic and reconstructive surgical teams. Early outcome following surgery was excellent. This case illustrates the need for a combined surgical approach for such a lesion and we believe it is the first reported case of plexiform neurofibroma of the sympathetic trunk.

Female↗

PubMed1997