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J Edwards

Publications and source records attributed to J Edwards.

At least 91 records · Page 5Linked to original sources
PubMed2001

Isolation of bovine viral diarrhea virus from a free-ranging mule deer in Wyoming.

A noncytopathic type 1a bovine viral diarrhea virus (BVDV) was isolated from a free-ranging yearling female mule deer (Odocoileus hemionus) from northwestern Wyoming (USA). The mule deer was emaciated, weak, and salivating, and Arcanobacterium pyogenes was cultured from lung abscesses. Bovine viral diarrhea virus was isolated from lung, however, BVDV antigen was not detected by immunohistochemistry. The BVDV genotype was determined by reverse transcriptase polymerase chain reaction and the RNA sequences from the 5'UTR and E2 genes compared with sequences of a type 1a BVDV isolated from cattle from the same area as the deer. The sequences from the deer BVDV were distinct from those of the bovine type 1a BVDV, but similar to other bovine type 1a BVDVs. Seventy-four (60%) of 124 sera collected from mule deer in this area had serum neutralizing antibody titers to type 1a BVDV of > or = 1:32. The high prevalence of seropositive mule deer and isolation of BVDV suggests that this virus circulates in the mule deer population. The isolate described in this report is the second reported BVDV isolate from free-ranging deer in North America and the first from a mule deer.

Animal Diseases↗
PubMed2001

Potential dermal and inhalation exposure to chlorpyrifos in Australian pesticide workers.

Chlorpyrifos inhalation, dermal exposure and working practices of 28 pesticide applicators in Western Australia were assessed during a series of single property applications of a 0.5% (n=2) or 1% (n=26) concentration of active ingredient in water solution. Deposition on new cotton gloves worn beneath applicators' usual protective gloves was 2.4 (range 0.12-86.1) mg h(-1). Median deposition of chlorpyrifos onto a new cotton overall worn over other clothing (24 sections removed, corrected for body proportions) was 11.1 (range 0.2-41.9) mg h(-1). Deposition onto seven patches taped to the applicators' skin was 0.04 (range 0.01-4.7) mg h(-1). Inhalation concentration was 5.7 (range 0.7-219) microg m(-3) time weighted average. In one group of 17 applicators' applying to existing properties, breathing zone air concentration correlated (P<0.05) with ambient air temperature (15-38 degrees C). The questionnaire results (29 respondents) indicated applicators' practices led to increased exposure, in particular concerning poor usage and condition of protective equipment and a high frequency of splashes and spills onto the body. Prevention of deposition on clothing, in particular on the lower body is suggested, as well as improved working practices.

Chlorpyrifos↗
PubMed2000

Sequence and analysis of chromosome 5 of the plant Arabidopsis thaliana.

The genome of the model plant Arabidopsis thaliana has been sequenced by an international collaboration, The Arabidopsis Genome Initiative. Here we report the complete sequence of chromosome 5. This chromosome is 26 megabases long; it is the second largest Arabidopsis chromosome and represents 21% of the sequenced regions of the genome. The sequence of chromosomes 2 and 4 have been reported previously and that of chromosomes 1 and 3, together with an analysis of the complete genome sequence, are reported in this issue. Analysis of the sequence of chromosome 5 yields further insights into centromere structure and the sequence determinants of heterochromatin condensation. The 5,874 genes encoded on chromosome 5 reveal several new functions in plants, and the patterns of gene organization provide insights into the mechanisms and extent of genome evolution in plants.

Animals↗
PubMed2000

Effects of vagus nerve stimulation on respiration during sleep: a pilot study.

BACKGROUND: Vagus nerve stimulation (VNS) is associated with respiratory effects such as hoarseness, dyspnea, and laryngeal irritation. The effects of VNS on sleep-related breathing in humans have not been reported previously. METHODS: Four epilepsy patients underwent polysomnography (PSG) before and after 3 months of treatment with VNS. Two of the four patients also underwent follow-up PSG to assess the effects of changing stimulus parameters on sleep-related breathing. RESULTS: All patients showed consistent sleep-related decreases in airflow and effort coinciding with VNS activation, although most events did not meet laboratory criteria for apneas or hypopneas. Apneas and hypopneas were more frequent during VNS activation than during nonactivation. Apnea-hypopnea index (AHI) for three subjects during VNS treatment PSG was <5 apneas and hypopneas/hour. In one patient with obstructive sleep apnea (OSA) before VNS treatment, AHI rose from 4 (pretreatment) to 11.3 (treatment). In this patient and in another patient without clinically significant OSA, lowering stimulus frequency, but not stimulus intensity, pulse width, or on-time, ameliorated VNS-related apneas and hypopneas. CONCLUSIONS: VNS is associated with adverse changes in respiration during sleep. In patients without preexisting OSA, this VNS effect is probably not clinically significant. In patients with preexisting OSA, VNS should be administered with care. Lowering VNS stimulus frequency or prolonging off-time may prevent exacerbation of OSA.

Adult↗
PubMed2000

A distinctive clade B HIV type 1 is heterosexually transmitted in Trinidad and Tobago.

HIV-1 transmission worldwide is predominantly associated with heterosexual activity, and non-clade B viruses account for the most spread. The HIV-1 epidemic in Trinidad/Tobago and the Caribbean shares many features with such heterosexual epidemics, including a prominent role for coincident sexually transmitted diseases. This study evaluates the molecular epidemiology of HIV-1 in Trinidad/Tobago during a period when abrupt transition from homosexual to heterosexual transmission occurred in the absence of injecting drug use, concomitant with a rapid rise in HIV-1 prevalence in the heterosexual population. Of 31 viral isolates studied during 1987-1995, all cluster with subtype B reference strains. In the analysis of full env genes from 22 early seroconverters, the Trinidad isolates constitute a significant subcluster within the B subtype. The Trinidad V3 consensus sequence differs by a single amino acid from the prototype B V3 consensus and demonstrates stability over the decade of this study. In the majority of isolates, the V3 loop of env contains a signature threonine deletion that marks the lineage of the Trinidad HIV-1 clade B epidemic from pre-1984. No phenotypic features, including syncitium induction, neutralization profiles, and chemokine receptor usage, distinguish this virus population from other subtype B viruses. Thus, although the subtype B HIV-1 viruses being transmitted in Trinidad are genetically distinguishable from other subtype B viruses, this is probably the result of a strong founder effect in a geographically circumscribed population rather than genetic selection for heterosexual transmission. These results demonstrate that canonical clade B HIV-1 can generate a typical heterosexual epidemic.

Amino Acid Sequence↗
PubMed2000

Selection of protective action guides for nuclear incidents. EPA.

In 1991 the Environmental Protection Agency (EPA) published its revised Manual of Protective Action Guides and Protective Actions for Nuclear Incidents. The protective action guides contained in the manual represent EPA's formal recommendations to Federal, State, and local emergency response officials for protecting public health and safety during a nuclear incident. These guides are expressed in terms of the projected dose at which action(s) should be taken to reduce or eliminate that dose. In determining the appropriate values for the protective action guides, the Agency considered the following four principles: (1) acute health effects should be avoided, (2) the risk of delayed health effects should be minimized, (3) the values should not be higher than justified by a cost-benefit analysis, and (4) the risk to health from implementing the protective action should not be greater than the risk from the dose avoided. This paper examines each of these principles and their application in the selection of the evacuation and sheltering protective action guides for the early, or immediate, phase of a nuclear incident.

Disaster Planning↗
PubMed2000

Interaction of the gonococcal porin P.IB with G- and F-actin.

The invasion of epithelial cells by N. gonorrheae is accompanied by formation of a halo of actin filaments around the enveloped bacterium. The transfer of the bacterial major outer membrane protein, porin, to the host cell membrane during invasion makes it a candidate for a facilitator for the formation of this halo. Western analysis shows here that gonococcal porin P.IB associates with the actin cytoskeleton in infected cells. Using the pyrene-labeled Mg forms of yeast and muscle actins, we demonstrate that under low ionic strength conditions, P.IB causes formation of filamentous actin assemblies, although they, unlike F-actin, cannot be internally cross-linked with N,N'-4-phenylenedimaleimide (PDM). In F-buffer, low porin concentrations appear to accelerate actin polymerization. Higher P.IB concentrations lead to the formation of highly decorated fragmented F-actin-like filaments in which the actin can be cross-linked by PDM. Co-assembly of P.IB with a pyrene-labeled mutant actin, S(265)C, prevents formation of a pyrene excimer present with labeled S(265)C F-actin alone. Addition of low concentrations of porin to preformed F-actin results in sparsely decorated F-actin. Higher P.IB concentrations extensively decorate the filaments, thereby altering their morphology to a state like that observed when the components are copolymerized. With preformed labeled S(265)C F-actin, P.IB quenches the pyrene excimer. This decrease is prevented by the F-actin stabilizers phalloidin and to a lesser extent beryllium fluoride. P.IB's association with the actin cytoskeleton and its ability to interact with and remodel actin filaments support a direct role for porin in altering the host cell cytoskeleton during invasion.

Actins↗
PubMed2000

Comparative genomic sequence analysis of the human and mouse cystic fibrosis transmembrane conductance regulator genes.

The identification of the cystic fibrosis transmembrane conductance regulator gene (CFTR) in 1989 represents a landmark accomplishment in human genetics. Since that time, there have been numerous advances in elucidating the function of the encoded protein and the physiological basis of cystic fibrosis. However, numerous areas of cystic fibrosis biology require additional investigation, some of which would be facilitated by information about the long-range sequence context of the CFTR gene. For example, the latter might provide clues about the sequence elements responsible for the temporal and spatial regulation of CFTR expression. We thus sought to establish the sequence of the chromosomal segments encompassing the human CFTR and mouse Cftr genes, with the hope of identifying conserved regions of biologic interest by sequence comparison. Bacterial clone-based physical maps of the relevant human and mouse genomic regions were constructed, and minimally overlapping sets of clones were selected and sequenced, eventually yielding approximately 1.6 Mb and approximately 358 kb of contiguous human and mouse sequence, respectively. These efforts have produced the complete sequence of the approximately 189-kb and approximately 152-kb segments containing the human CFTR and mouse Cftr genes, respectively, as well as significant amounts of flanking DNA. Analyses of the resulting data provide insights about the organization of the CFTR/Cftr genes and potential sequence elements regulating their expression. Furthermore, the generated sequence reveals the precise architecture of genes residing near CFTR/Cftr, including one known gene (WNT2/Wnt2) and two previously unknown genes that immediately flank CFTR/Cftr.

Animals↗
PubMed2000

Fetoprotectivity of the flavanolignan compound siliphos against ethanol-induced toxicity.

Of the three flavanolignans that are found in silymarin (Silybum marianum [L.] Gaertn.), silybin is thought to be the primary therapeutic constituent. To test the capacity of silybin to protect the rat fetus from toxic effects of maternally ingested EtOH we did the following: Adult female rats were assigned to one of four groups; EtOH, EtOH/silybin, pair-fed control, and chow fed control. Silybin was orally administered as Siliphos(R), which is one part silybin to two parts phosphatidylcholine. All groups except the chow-fed control were maintained on a liquid diet throughout pregnancy. On day 21 of pregnancy the rats were killed and the fetuses removed. Gamma glutamyl transpeptidase (GGTP) activity and glutathione (GSH) levels were determined for liver and brain tissue for both the fetuses and the dams. Maternal and fetal GGTP activity in the EtOH rats was significantly higher than that of pair-fed controls, whereas the GGTP activity observed in the Siliphos(R)/EtOH rats was not elevated. Fetal mortality rates in the EtOH rats significantly exceeded those of all three other groups.

Administration, Oral↗
PubMed2000

Interventions for treating plantar heel pain.

BACKGROUND: Ten percent of people may experience pain under the heel (plantar heel pain) at some time. Injections, insoles, heel pads, strapping and surgery have been common forms of treatment offered. The absolute and relative effectiveness of these interventions are poorly understood. OBJECTIVES: The objective of this review was to identify and evaluate the evidence for effectiveness of treatment in treating plantar heel pain. SEARCH STRATEGY: MEDLINE (from 1966 to December 1997), EMBASE and the Cochrane Library were searched. Three podiatry journals (The Foot, The Chiropodist (later The Journal of British Podiatric Medicine), and The British Journal of Podiatric Medicine) were handsearched. We contacted known investigators in the field to identify unpublished data or research in progress. Non English language reports were excluded from the review. SELECTION CRITERIA: Randomised and quasi randomised trials of interventions for plantar heel pain in adults. DATA COLLECTION AND ANALYSIS: Two reviewers independently evaluated studies for inclusion, extracted data and assessed study quality. Additional information was obtained by direct contact with investigators. No poolable data were identified. Where measures of variance were available we have calculated the weighted mean differences based on visual analogue scale (VAS) scores. MAIN RESULTS: Eleven randomised trials involving 465 participants were included. Study quality was generally poor, and pooling of data was not possible. All studies measured a reduction in heel pain as the primary outcome. Seven trials evaluated interventions against placebo/dummy or no treatment. There was limited evidence for the effectiveness of topical corticosteroid, administered by iontophoresis in reducing pain. There was no evidence for the effectiveness of injected corticosteroid. There was limited evidence for the effectiveness of low energy extracorporeal shock wave therapy in reducing night pain, resting pain and pressure pain in the short term (12 weeks). In individuals with chronic pain (longer than six months), there was limited evidence for the effectiveness of dorsiflexion night splints in reducing pain. There was no evidence to support the effectiveness of therapeutic ultrasound, low-intensity laser therapy, exposure to an electron generating device or insoles with magnetic foil. No randomised trials evaluating orthotic devices, surgery, or radiotherapy against a control population were identified. There was limited evidence for the superiority of corticosteroid injections over orthotic devices. REVIEWER'S CONCLUSIONS: Although there is limited evidence for the effectiveness of local corticosteroid therapy, the effectiveness of other frequently employed treatments in altering the clinical course of plantar heel pain has not been established in comparative studies. Well designed and conducted randomised studies are required.

Adrenal Cortex Hormones↗
PubMed2000

Single dose paracetamol (acetaminophen), with and without codeine, for postoperative pain.

BACKGROUND: Patient surveys have shown that postoperative pain is often not managed well, and there is a need to assess the efficacy and safety of commonly used analgesics as newer treatments become available. Paracetamol (acetaminophen) is an important non-opiate analgesic, commonly prescribed, as well as being available for retail sale. This review seeks to examine the efficacy of paracetamol alone and in combination with codeine, and also considers adverse effects. OBJECTIVES: To assess the analgesic efficacy and adverse effects of a single dose of oral paracetamol (acetaminophen) alone and in combination with codeine for moderate to severe postoperative pain. SEARCH STRATEGY: Published trials were identified from: Medline (1966 to May 1996), Embase (1980 to 1996), Cochrane Library (Issue 2 1996) and the Oxford Pain Relief Database (1950 to 1994). Additional trials were identified from reference lists of retrieved studies. Date of most recent searches: July 1998. SELECTION CRITERIA: Inclusion criteria were: full journal publication, postoperative pain, postoperative oral administration, adult patients, baseline pain of moderate to severe intensity, double-blind design, and random allocation to treatment groups which compared paracetamol with placebo or a combination of paracetamol and codeine with either placebo or the same dose of paracetamol alone. DATA COLLECTION AND ANALYSIS: Data were extracted by two independent reviewers, and trials were quality scored. Summed pain intensity and pain relief data were extracted and converted into dichotomous information to yield the number of patients with at least 50% pain relief. This was used to calculate the relative benefit and number-needed-to-treat (NNT) for one patient to achieve at least 50% pain relief over 4 to 6 hours compared with placebo. Adverse effects were used to calculate relative risk and number-needed-to-harm (NNH). MAIN RESULTS: We found 40 trials of paracetamol against placebo (4171 patients), 22 trials of paracetamol plus codeine against placebo (1407 patients) and 12 trials of paracetamol plus codeine against the same dose of paracetamol (794 patients). In postoperative pain paracetamol 1000 mg had an NNT of 4.6 (3.8-5.4) for at least 50% pain relief when compared with placebo, and paracetamol 600/650 mg had an NNT of 5.3 (4.1-7.2). Paracetamol 600/650 mg plus codeine 60 mg had an NNT of 3. 6 (2.9-4.5). Comparing paracetamol plus codeine 60 mg with the same dose of paracetamol alone gave an NNT of 7.7 (5.1-17) for at least 50% pain relief. Adverse effects: Relative risk estimates for paracetamol 600/650 mg plus codeine 60 mg versus placebo showed a significant difference for 'drowsiness'/somnolence (NNH 11 (7.5- 0)) and dizziness (NNH 27 (15-164)) but no significant difference for nausea/vomiting. REVIEWER'S CONCLUSIONS: Paracetamol is an effective analgesic with a low incidence of adverse effects. The addition of codeine 60 mg to paracetamol produces additional pain relief even in single oral doses, but may be accompanied by an increase in drowsiness and dizziness.

Acetaminophen↗
PubMed2000

How definition of mental health problems can influence help seeking in rural and remote communities.

The present study sought to understand the rural and remote influences on people's identification of, and response to, mental health problems. Twenty-two key informants living in northern and western South Australia were interviewed. They included mental health and generalist health professionals, other human service workers and mental health consumers. Three themes are reported here: reluctance to acknowledge mental health problems and the avoidance of appropriate help; stigma and the avoidance of mental health services; and the influence of rural and remote circumstances. Most informants considered that many mental health problems were amenable to help from generalist workers, with backup support from mental health specialists. Informants thought this intervention to be appropriate because a common view of mental health problems as 'insanity' and a culture of self-reliance created a reluctance to seek help from a mental health specialist. These themes need to be taken into account when designing mental health interventions for rural and remote communities.

Australia↗
PubMed2000

Is it feasible to construct a community profile of exposure to industrial air pollution?

OBJECTIVE: An epidemiological investigation to assess the validity of residential proximity to industry as a measure of community exposure. METHODS: 19 Housing estates in Teesside (population 1991: 77 330) in north east England were grouped into zones: A=near; B=intermediate; C=further from industry. With residential proximity of socioeconomically matched populations as a starting point a historical land use survey, historical air quality reports, air quality monitoring, dispersion modelling data, and questionnaire data, were examined. RESULTS: The populations in zones A, B, and C were similar for socioeconomic indicators and smoking history. Areas currently closest to industry had also been closest for most of the 20th century. Historical reports highlighted the influence of industrial emissions to local air quality, but it was difficult to follow spatial pollution patterns over time. Whereas contemporary NO(x) and benzene concentrations showed no geographical variation, dispersion modelling of emissions (116 industrial stacks, traffic, and domestic sources) showed a gradient associated with industry. The presumed exposure gradient of areas by proximity to industry (A>B>C) was evident for all of zone A and most of zones B and C. CONCLUSIONS: It was feasible to assemble a picture of community exposure by integration of measurements from different sources. Proximity of residence was a reasonable surrogate for complex community exposure.

Air Pollutants↗