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V Hawkins

Publications and source records attributed to V Hawkins.

7 recordsLinked to original sources
PubMed2000

The prostate expression database (PEDB): status and enhancements in 2000.

The Prostate Expression Database (PEDB) is an online resource designed to access and analyze gene expression information derived from the human prostate. PEDB archives >55 000 expressed sequence tags (ESTs) from 43 cDNA libraries in a curated relational database that provides detailed library information including tissue source, library construction methods, sequence diversity and sequence abundance. The differential expression of each EST species can be viewed across all libraries using a Virtual Expression Analysis Tool (VEAT), a graphical user interface written in Java for intra- and inter-library species comparisons. Recent enhancements to PEDB include: (i) the functional categorization of annotated EST assemblies using a classification scheme developed at The Institute for Genome Research; (ii) catalogs of expressed genes in specific prostate tissue sources designated as transcriptomes; and (iii) the addition of prostate proteome information derived from two-dimensional electrophoreses and mass spectrometry of prostate cancer cell lines. PEDB may be accessed via the WWW at http://www.mbt.washington.edu/PEDB/

Databases, Factual↗
PubMed2000

Colloid solutions for fluid resuscitation.

BACKGROUND: Colloids are widely used in the replacement of fluid volume, however doubts remain as to their benefits. Different colloids vary in their molecular weight and therefore in the length of time they remain in the circulatory system. Because of this and their other characteristics, they may differ in their safety and efficacy. OBJECTIVES: To compare the effects of different colloid solutions in patients thought to need volume replacement. SEARCH STRATEGY: The Cochrane Injuries Group specialised register, The Cochrane Controlled trials register (all years), MEDLINE (1994-98), EMBASE (1974-98) were searched. Bibliographies of trials retrieved were searched and drug companies manufacturing colloids were contacted for information. SELECTION CRITERIA: Randomised and quasi randomised trials comparing colloid solutions in critically ill and surgical patients thought to need volume replacement. The main outcomes measured were death, amount of whole blood transfused and incidence of adverse reactions. DATA COLLECTION AND ANALYSIS: Two authors independently extracted the data and assessed the quality of the trials. MAIN RESULTS: 46 trials met the inclusion criteria, with a total of 2884 participants. Many of the trials were small. In the majority of trials quality was poor or uncertain. Deaths were obtained from 27 trials. Twenty three trials recorded the amount of blood transfused, however quantitative analysis was not possible due to skewness and variable reporting. Thirteen trials recorded adverse reactions, but none occurred. For albumin or PPF versus hydroxyethyl starch (HES) 20 trials reported mortality. The pooled relative risk (RR) was 1.17 (95% CI 0.91, 1.50). For albumin or PPF versus gelatin 3 trials reported mortality. The RR was 0.99 (0.69, 1.42). For gelatin vs HES 3 trials reported mortality, RR was 0.97 (0.65, 1.44). RR was not estimable in the albumin vs dextran, gelatin vs dextran, and HES vs dextran groups. REVIEWER'S CONCLUSIONS: From this review, there is no evidence that one colloid solution is more effective or safe than any other, although the confidence intervals are wide and do not exclude clinically significant differences between colloids. Larger trials of fluid therapy are needed if clinically significant differences in mortality are to be detected or excluded.

Blood Proteins↗
PubMed1999

Negative selection: a method for obtaining low-abundance cDNAs using high-density cDNA clone arrays.

The identification of the entire complement of genes expressed in a cell, tissue, or organism provides a framework for understanding biological properties and establishes a tool set for subsequent functional studies. The large-scale sequencing of randomly selected clones from cDNA libraries has been successfully employed as a method for identifying a large fraction of these expressed genes. However, this approach is limited by the inherent redundancy of cellular transcripts reflecting widely variant levels of gene transcription. As a result, a high percentage of transcript duplications are encountered as the number of sequenced clones accrues. To address this problem, we have developed a negative hybridization selection method that employs the hybridization of complex cDNA probes to high-density arrays of cDNA clones and the subsequent selection of clones with a null or low hybridization signal. This approach was applied to a cDNA library constructed from normal human prostate tissue and resulted in the reduction of highly expressed prostate cDNAs from 6.8 to 0.57% with an overall decline in clone redundancy from 33 to 11%. The selected clones also reflected a more diverse cDNA population, with 89% of the clones representing distinctly different cDNAs compared with 67% of the randomly selected clones. This method compares favorably with cDNA library re-association normalization approaches and offers several distinct advantages, including the flexibility to use previously prepared libraries, and the ability to employ an iterative screening approach for continued accrual of cDNAs representing rare transcripts.

DNA, Complementary↗
PubMed1999

PEDB: the Prostate Expression Database.

The Prostate Expression Database (PEDB) is a curated relational database and suite of analysis tools designed for the study of prostate gene expression in normal and disease states. Expressed Sequence Tags (ESTs) and full-length cDNA sequences derived from more than 40 human prostate cDNA libraries are maintained and represent a wide spectrum of normal and pathological conditions. Detailed library information including tissue source, library construction methods, sequence diversity and abundance are available in a library archive. Prostate ESTs are assembled into distinct species groups using the multiple alignment program CAP2 and are annotated with information from the GenBank, dbEST and Unigene public sequence databases. Annotated sequences in PEDB are searched using the BLAST algorithm. The differential expression of each EST species can be viewed across all libraries using a Virtual Expression Analysis Tool (VEAT), a graphical user interface written in Java for intra- and inter-library species comparisons. PEDB may be accessed via the World Wide Web at http://www.mbt.washington.edu/PEDB/

Base Sequence↗
PubMedDate not supplied

Kynostatin and 17beta-estradiol prevent the apoptotic death of human neuroblastoma cells exposed to HIV-1 protease.

A significant number of adult male patients with acquired immunodeficiency syndrome develop cerebral atrophy and progressive brain disorders such as dementia complex and neuropsychiatric problems. Upon entering the brain via activated macrophages or microglias, the human immunodeficiency type 1 virus (HIV-1) may produce cytotoxic factors such as HIV-1 envelope protein (gp120) and protease. Owing to significant proteolysis of nonviral proteins, the protease derived from HIV-1 may be detrimental to brain cells and neurons. Our results revealed that HIV-1 protease, at nanomolar concentrations, was as potent as gp120 in causing neurotoxicity in human neuroblastoma neurotypic SH-SY5Y cells. As shown by the Oncor ApopTag staining procedure, HIV-1 protease significantly increased the number of apoptotic cells over the serum-free controls. Moreover, HIV-1 protease-induced neurotoxicity was blocked by a selective protease inhibitor, kynostatin (KNI-272). Antioxidants such as 17beta-estradiol, melatonin, and S-nitrosoglutathione also prevented protease-induced neurotoxicity. These findings indicate that oxidative proteolysis may mediate HIV-1 protease-induced apoptosis and the degeneration of neurons and other brain cells. Centrally active protease inhibitors and antioxidants may play an important role in preventing cerebral atrophy and associated dementia complex caused by HIV-1.

Antioxidants↗