Search PubMed⌕ Search

Biomedical subjects

P Ford

Publications and source records attributed to P Ford.

At least 19 recordsLinked to original sources
PubMed2006

Deficiency of iNOS contributes to Porphyromonas gingivalis-induced tissue damage.

Periodontitis is a chronic inflammatory disease that results in extensive soft and hard tissue destruction of the periodontium. Porphyromonas gingivalis possesses an array of virulence factors and has been shown to induce expression of inducible nitric oxide synthase (iNOS) in inflammatory cells. The aim of this study was to investigate the effect of eliminating iNOS in a murine model of P. gingivalis infection. This was achieved by utilizing a P. gingivalis-induced skin abscess model, and an alveolar bone loss model employing an oral infection of P. gingivalis in iNOS knockout mice. The results indicated that iNOS knockout mice exhibit more extensive soft tissue damage and alveolar bone loss in response to P. gingivalis infection compared to wild-type mice. The local immune response to P. gingivalis in iNOS knockout mice was characterized by increased numbers of polymorphonuclear monocytes, while the systemic immune response was characterized by high levels of interleukin-12. The iNOS is required for an appropriate response to P. gingivalis infection.

Abscess↗
PubMed2005

Asymmetry in the osmotic response of a rat cortical collecting duct cell line: role of aquaporin-2.

Transition from antidiuresis to diuresis exposes cortical collecting duct cells (CCD) to asymmetrical changes in environment osmolality, inducing an osmotic stress, which activates numerous membrane-associated events. The aim of the present work was to investigate, either in the presence or not of AQP2, the transepithelial osmotic water permeability (P(osm)) following cell exposure to asymmetrical hyper- or hypotonic gradients. For this purpose, transepithelial net volume fluxes were recorded every minute in two CCD cell lines: one not expressing AQPs (WT-RCCD(1)) and another stably transfected with AQP2 (AQP2-RCCD(1)). Our results demonstrated that the rate of osmosis produced by a given hypotonic shock depends on the gradient direction (osmotic rectification) only in the presence of apical AQP2. In contrast, hypertonic shocks elicit P(osm) rectification independently of AQP2 expression, and this phenomenon may be linked to modulation of basolateral membrane permeability. No asymmetry in transepithelial resistance was observed under hypo- or hypertonicity, indicating that rectification cannot be attributed to a shunt through the tight junction path. We conclude that osmotic rectification may be explained in terms of dynamical changes in membrane permeability probably due to activation/incorporation of AQPs or transporters to the plasma membrane via some mechanism triggered by osmolality.

Animals↗
PubMed2003

An evaluation of the flexiguide introducer with the flexible laryngeal mask airway.

Insertion of the flexible Laryngeal Mask Airway has been achieved by a variety of techniques. We have evaluated the Flexiguide for aiding introduction of a flexible Laryngeal Mask Airway in 100 anaesthetised patients. We were successful in establishing a clear airway on the first attempt on 84 (84%) occasions and within two attempts in 97 (97%). The positioning of the laryngeal mask airway was assessed by five measures and was optimally placed in 85% of cases and good in 96%. A clear airway was achieved in 92% of cases. Insertion of the flexible Laryngeal Mask Airway with the Flexiguide was easy in 82 (82%) and slightly difficult in 15 (15%) of cases. Removal of the Flexiguide from the device was easy in 95 (95%) of cases. Airway manoeuvres were used to assist airway placement in 55% of cases with jaw thrust being most common. Minor complications occurred in three (3%) patients: two coughed and one experienced minor tissue trauma during mask insertion. There were no complications associated with use of the Flexiguide during the procedure or after anaesthesia. The Flexiguide is a useful tool to assist insertion of the flexible Laryngeal Mask Airway and is associated with few complications.

Adolescent↗
PubMed2002

Differential role of Na+/H+ exchange isoforms NHE-1 and NHE-2 in a rat cortical collecting duct cell line.

The Na+/H+ exchanger (NHE) constitutes a gene family containing several isoforms that display different membrane localization and are involved in specialized functions. Although basolateral NHE-1 activity was described in the cortical collecting duct (CCD), the localization and function of other NHE isoforms is not yet clear, This study examines the expression, localization, and regulation of NHE isoforms in a rat cortical collecting duct cell line (RCCD1) that has previously been shown to be a good model of CCD cells. Present studies demonstrate the presence of NHE-1 and NHE-2 isoforms, but not NHE-3 and NHE-4, in RCCD1 cells. Cell monolayers, grown on permeable filters, were placed on special holders allowing independent access to apical and basolateral compartments. Intracellular pH (pHi) regulation was spectrofluorometrically studied in basal conditions and after stimulation by NH4Cl acid load or by a hyperosmotic shock. In order to differentiate the roles of NHE-1 and NHE-2, we have used HOE-694, an inhibitor more selective for NHE-1 than for NHE-2. The results obtained strongly suggest that NHE-1 and NHE-2 are expressed in the basolateral membrane but that they have different roles: NHE-1 is responsible for pHi recovery after an acid load and NHE-2 is mainly involved in steady-state pHi and cell volume regulation.

Animals↗
PubMed2001

A comparison of manometric and membrane-electrode procedures for measuring rates of leaf decay.

Two instruments were compared for consistency of decay-rate measurements of four leaf types: Lolium perenne, Typha domingenesis, Casuarina cunninghamiana and Eucalyptus polyanthemos, via progressive biological oxygen demand (BOD). The instruments were (a) a dissolved oxygen probe (i.e. an oxygen-selective membrane electrode) used in two different modes: (1) measurements of sacrificial samples that were successively discarded, and (2) repeated measurements of the same sample, and (b) a mercury free manometer. Measurements of D-glucose:glutamic acid standards were similar for both instruments, and corresponded with values expected after five days of decay. During five days decay of the four leaf types, progressive measurements obtained by both applications of the dissolved oxygen probe were similar, and could be related linearly. Progressive leaf-decay measurements obtained by the manometer and dissolved oxygen probe could be related linearly also. Decay measurements obtained by both instruments were nearly identical for C. cunninghamiana and E. polyanthemos, but there were slight differences in the slopes of linear relationships for L. perenne and T. domingenesis. These comparisons indicate the feasibility of using both instruments for obtaining comparable measurements of leaf decay rates. It is also feasible to briefly reopen the same glass bottle to facilitate temporal BOD measurements with the dissolved oxygen probe. However, because slight differences in decay rates were evident in two comparisons, care should be exercised to derive and verify the association of data between instruments.

Biodegradation, Environmental↗
PubMed2001

A special case.

Explore the source record for details and available documents.

Aged↗
PubMed2000

Water permeability in rat oocytes at different maturity stages: aquaporin-9 expression.

Important functional and structural modifications occur in mammalian oocytes during their arrival to maturity. In this process, oocytes switch from a high activity level, implying an important metabolic rate and a coordinated movement of water and solutes, to a lower functional state. The aim of this work was to study the mechanisms involved in water movements during oocyte arrival to maturity. Volume changes, induced by an osmotic gradient, were followed by video microscopy in rat oocytes. The water osmotic permeability (P(osm)) of immature oocytes (proestrus) was sensitive to HgCl(2) and phloretin. In contrast, mature oocytes (estrus) had a reduced P(osm) that was not sensitive to these compounds. When proestrus oocytes were incubated in vitro at 37 degrees C they spontaneously arrived at maturity and its P(osm) decreased between four and six hours of incubation. RT-PCR experiments were performed using specific primers for all rat aquaporins that had been cloned. We found that aquaporin-9 transcript (AQP9) is present in proestrus oocytes but not in estrus oocytes. AQP9 has been recently described as a "broad selective channel" responsible for solute and water transfers in highly active cells. Our experiments showed that proestrus oocytes, but not estrus, are permeable to mannitol. It is concluded that during the process of maturation, P(osm) decreases and AQP9 transcripts disappear. We report here the first study correlating water permeability and aquaporin mRNA expression in mammalian oocytes.

Animals↗
PubMed2000

Mind-body innovations--an integrative care approach.

Integration of behavioral health and medicine has gained increased support recently within the new field of complementary medicine. Providers from both disciplines are acknowledging the "mind-body" connection and recognizing the value of treating the "whole" patient through working within an integrative delivery model. This paper describes two treatment programs which were developed using the principles of the mind-body connection and implemented within an integrative setting at a large HMO. The results of research studies are presented and discussed to demonstrate the efficacy of these programs.

Adult↗
PubMed2000

Future directions for gerontology: a nursing perspective.

This paper discusses the contribution nursing has made to the development of person-centred services, and the influence of gerontology upon such developments. It examines traditional attitudes to medicine and nursing, when curing was all-important and caring treated as secondary and the shift away from this attitude to a more holistic approach to nursing, where the dignity of the patient is an important issue. It argues that good practice utilizes different sources of knowledge, including intuitive knowledge, and discusses the integrated programme of policy, development, research and education activities that the Royal College of Nursing is developing. The options currently available to anyone wishing to study gerontology are discussed, and the pros and cons of the current emphasis on broad-based clinical and educational experience prior to specialization analysed. The key aim of the RCN is to develop the specialism of gerontological nursing and the quality of care experienced by older people. With this end in view, this paper describes the education programme being developed by the RCN, leading to the award of Gerontological Nurse Specialist--a person able to demonstrate knowledge of rehabilitation, clinical assessment, health care assessment and a holistic knowledge of the ageing process.

Aged↗
PubMed1999

Familial antiphospholipid antibody syndrome: criteria for disease and evidence for autosomal dominant inheritance.

OBJECTIVE: To develop diagnostic criteria for a familial form of antiphospholipid antibody syndrome (APS), identify families with >1 affected member, examine possible modes of inheritance, and determine linkage to potential candidate genes. METHODS: Family members of probands with primary APS were analyzed for clinical and laboratory abnormalities associated with APS. Families with > or =2 affected members were analyzed by segregation analysis and typed for candidate genetic markers. RESULTS: Seven families were identified. Thirty of 101 family members met diagnostic criteria for APS. Segregation studies rejected both environmental and autosomal recessive models, and the data were best fit by either a dominant or codominant model. Linkage analysis showed independent segregation of APS and several candidate genes. CONCLUSION: Clinical and laboratory criteria are essential to identify the spectrum of disease associated with APS. We believe a set of criteria was developed that can precisely define affected family members with APS. Modeling studies utilizing these criteria strongly support a genetic basis for disease in families with APS and suggest that a susceptibility gene is inherited in an autosomal dominant pattern. However, in these families, APS was not linked with HLA, Fas, or other candidate genes, including beta2-glycoprotein 1, HLA, T cell receptor beta chain, Ig heavy chain, antithrombin III, Fas ligand, factor V, complement factor H, IgK, and Fas.

Adolescent↗
PubMed1999

Urban and rural suicide differentials in migrants and the Australian-born, New South Wales, Australia 1985--1994.

We estimated risk of suicide in adults in New South Wales (NSW) by sex, country of birth and rural/urban residence, after adjusting for age; we also examined youth suicide (age 15-24 years). The study population was the entire population of NSW, Australia, aged > or =15 years during the period 1985-1994. Poisson regression was used to examine the relationship between predictor variables and the risk of suicide, with the focus on migrant status and area of residence. A significantly higher risk of suicide was found in male migrants from Northern Europe and Eastern Europe/former USSR, compared to Australian-born males; a significantly lower suicide risk occurred in males from Southern Europe, the Middle East and Asia. In female migrants, those from UK/Eire, Northern Europe, Eastern Europe/former USSR and New Zealand exhibited a significantly higher risk of suicide compared to Australian-born females. A significantly lower risk of suicide occurred in females from the Middle East. Male migrants overall were at significantly lower risk of suicide than the Australian-born, while female migrants overall had a significantly higher risk of suicide than Australian-born females. Among migrant males overall, the rural-urban suicide risk differential was significantly higher for those living in non-metropolitan areas (RR = 1.9; 95% CI: 1.7-2.1). Suicide risk was significantly higher in non-metropolitan male immigrants from the UK/Eire (RR = 1.4; 95% CI: 1.1-1.7), Southern Europe (RR = 1.7; 95% CI: 1.2-2.4), Northern/Western Europe (1.5; 95% CI: 1.2-1.9), the Middle East (RR = 3.8; 95% CI: 1.9-7.8), New Zealand (RR = 1.4; 95% CI: 1.0-1.8) and 'other' (RR = 2.6; 95% CI: 1.9-3.5), when compared to their urban counterparts. There was no statistically significant difference in suicide risk between rural and urban Australian-born males. For female suicide, significantly lower risk was found in female immigrants living in non-metropolitan areas who were from Northern/Western Europe (RR = 0.7; 95% CI: 0.4-0.96), as well as the Australian-born (RR = 0.7; 95% CI: 0.6-0.8), when compared to their urban counterparts. The non-metropolitan/metropolitan relative risk for suicide in female migrants overall was not significantly different from one. Among male youth there was a significantly higher suicide risk in non-metropolitan areas, with a relative risk estimate of 1.4 for Australian-born youth (95% CI: 1.2-1.5) and 1.7 for migrant youth (95% CI: 1.2-2.4), when compared with metropolitan counterparts. We conclude that suicide among migrant males living in non-metropolitan areas accounts for most of the excess of male suicide in rural NSW, and the significantly lower risk of suicide for non-metropolitan Australian-born women does not apply to migrant women.

Adolescent↗
PubMed1999

Determining older people's need for registered nursing in continuing healthcare: the contribution of the Royal College of Nursing's Older People Assessment Tool.

This paper presents an overview of the work of the Royal College of Nursing (RCN) in developing an assessment tool to determine the need for registered nursing by older people in continuing care. In the past, healthcare has been provided free and social care 'means-tested'. The erosion of the NHS's responsibility for continuing care provision through the development of eligibility criteria has resulted in the majority of older people having their care services means-tested, including their nursing care. The RCN has argued that older people have inter-related health and social care needs, that nursing care is an integral component of healthcare provision and that therefore older people should not have to pay for nursing care. This paper describes the work undertaken by the RCN to develop a tool for use in assessing older people's need for registered nursing--'The RCN Nursing Older People Assessment Tool'. The underpinning theoretical framework is outlined and the process of constructing the tool is described. In addition, the stages of assessment using the tool are outlined. A pilot study in seven nursing homes managed by three different companies was undertaken to test the reliability and acceptability of the tool. 178 paired assessments were completed (89% of the intended sample). The results of the pilot study demonstrated that the tool has a high degree of reliability and acceptability.

Aged↗