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Biomedical subjects

K P Jones

Publications and source records attributed to K P Jones.

At least 19 recordsLinked to original sources
PubMed2006

Role of leucocytes in damage to the vascular endothelium during ischaemia-reperfusion injury.

During this investigation, a model of tourniquet-induced forearm ischaemia-reperfusion injury is employed to investigate the role of leucocytes in damage to the vascular endothelium during ischaemia-reperfusion injury. Leucocyte entrapment is investigated by measuring the concentration of leucocytes in venous blood leaving the arm. Neutrophil and monocyte leucocyte subpopulations are isolated by density gradient centrifugation techniques. Cell surface expression of CD11b and the intracellular production of hydrogen peroxide are measured via flow cytometry. Plasma concentrations of elastase and von Willebrand factor (vWF) are measured using enzyme-linked immunosorbemt assay (ELISA) techniques. During ischaemia-reperfusion, there was an increase in CD11b cell surface expression on neutrophils (P=0.040) and monocytes (P=0.049), and a decrease in peripheral blood leucocytes (P=0.019). There was an increase in the intracellular production of hydrogen peroxide by leucocyte subpopulations (P=0.027 [neutrophils], P=0.091 [monocytes]) and in the plasma elastase concentration (P=0.05). There was also a trend to increasing plasma concentration of vWF (P=0.0562), which was measured as a marker of endothelial damage. Ischaemia-reperfusion results in increased adhesiveness, entrapment and activation of leucocytes. Even following a mild ischaemic insult, this leucocyte response was followed immediately by evidence of endothelial damage. These results may have important implications for understanding the development of chronic diseases that involve mild ischaemic episodes.

Adult↗
PubMed2004

Human leucocyte antigen polymorphisms in nut-allergic patients in South Wales.

BACKGROUND: Peanuts and tree nuts are among the most common foods provoking severe allergic reactions including fatal anaphylaxis. However, little is known of the underlying genetic and immunological mechanisms involved. OBJECTIVE: Based on findings in other allergic diseases, we have investigated whether specific human leucocyte antigens (HLA) are associated with nut allergy. METHOD: Eighty-four patients presenting at the allergy clinic with symptoms of nut allergy were typed for the HLA Class I (HLA-A and B) and Class II (HLA-DRB1 and DQB1) loci by PCR using sequence-specific primers. Carriage frequencies were compared with 82 atopic non-nut-allergic subjects and 1798 random blood donors. RESULTS: The frequency of HLA-B(*)07 (28.57%) and DRB1(*)11 (15.48%) was increased in the nut-allergic patients compared to the atopic controls (12.20% and 3.66%, respectively) but not when compared to the blood donors (28.86% and 10.12%). DRB1(*)13 and DQB1(*)06 were both increased in frequency in the nut allergy patients over both the atopic and blood donor controls. However, none of these increased frequencies were significant when corrected for the number of comparisons undertaken. CONCLUSION: At HLA '2-digit resolution' and with undifferentiated patients with nut allergy, there are no major disturbances in the frequency of HLA-A, B, DRB1 or DQB1 types. However, the difference in frequency of HLA-DRB1(*)11 between the nut allergy patients and the atopic controls merits further investigation as this may represent an important phenotypic relationship.

Adolescent↗
PubMed2003

Honey stimulates inflammatory cytokine production from monocytes.

Clinical observations indicate that honey may initiate or accelerate the healing of chronic wounds and has, therefore, been claimed to have anti-inflammatory properties. The aim of this study was to investigate the effects of honey on the activation state of immunocompetent cells, using the monocytic cell line, MonoMac-6 (MM6), as a model. We investigated the effect of each of the three honeys (manuka, pasture and jelly bush) on the release of important inflammatory cytokines from MM6 cells. These honeys, together with a sugar syrup control (artificial honey), were incubated with MM6 cells at a concentration of 1% (w/v) for 0-24h. Cell culture supernatants were tested using specific ELISA assays for tumour necrosis factor-alpha (TNF-alpha) and interleukin (IL)-1beta and IL-6. All honeys significantly increased the TNF-alpha, IL-1beta and IL-6 release from MM6 cells (and human monocytes) when compared with untreated and artificial-honey-treated cells (P<0.001). Jelly bush honey significantly induced the maximal release of each cytokine compared with manuka, pasture or artificial honeys (P<0.001). These results suggest that the effect of honey on wound healing may in part be related to the stimulation of inflammatory cytokines from monocytic cells. Such cell types are known to play an important role in healing and tissue repair.

Cell Line↗
PubMed2002

Polymorphism in the STAT6 gene encodes risk for nut allergy.

Nut allergy is an important and potentially life threatening food allergy with a prevalence of one in 150 children in the UK population. STAT6 (signal transducer and activator of transcription) is an important molecule in the induction and regulation of an allergic response, which maps to chromosome 12q in a region previously linked with total serum IgE concentration and atopy in different populations. We have examined the frequency of a single nucleotide polymorphism (SNP) in the 3'UTR region of STAT6 gene in 71 UK Caucasoid patients diagnosed with nut allergy and 45 atopic patients without nut allergy using PCR-RFLP and compared these with 184 UK healthy controls. The STAT6 G allele frequency was significantly increased in nut allergy patients compared with blood donor controls (P < 0.0001, OR = 2.9, 95% CI: 1.7-4.9), which was under a recessive model (GG vs GA+AA, P = 0.0001, OR = 3.2, 95% CI: 1.7-5.8) but not in atopic patients without nut allergy. The G allele was most frequent in the severe cases and GG homozygosity was associated with the increased risk of severe reaction (OR = 3.9, 95% CI: 1.9-8.3). We conclude that STAT6 3'UTR polymorphism is associated with susceptibility and severity in nut allergic patients in our population.

Child↗
PubMed2001

Stimulation of TNF-alpha release in monocytes by honey.

Although evidence exists for the antibacterial effects of honey there is limited objective evidence for direct promotion of healing. We investigated the effect of manuka, pasture and an artificial honey on macrophage function. Reactive oxygen intermediate (ROI) production was assessed by luminol enhanced chemoluminescence and tumour necrosis factor-alpha (TNF-alpha) release was determined by immunoassay. ROI production was significantly (P<0.001) decreased by pasture honey and manuka honey. TNF-alpha release was significantly enhanced (P<0.001) in unprimed MM6 cells by manuka and pasture honey but was not altered in primed cells. These results could explain the suggested therapeutic properties of honey in promoting wound healing.

Cell Line↗
PubMed2001

Dipalmitoylphosphatidylcholine modulates inflammatory functions of monocytic cells independently of mitogen activated protein kinases.

Phosphatidylcholine (PC) is the major phospholipid of pulmonary surfactant and it is hypothesized that PC and its subspecies modulate the functions of alveolar macrophages. The most abundant of these subspecies is dipalmitoylphosphatidylcholine (DPPC). This study was undertaken to determine the effect of PC on monocyte function using a human monocytic cell line, MonoMac-6 (MM6). This study showed that preincubation of MM6 cells with DPPC at 125 microg/ml for 2 h inhibited the oxidative response to either zymosan or phorbol-12-myristate-13-acetate (PMA) by 30% (P < 0.001). This inhibition with DPPC was independent of LPS priming. When DPPC was replaced with 1-palmitoyl-2-arachidonoyl phosphatidylcholine (PAPC) there was no inhibition and in contrast a significant increase in oxidant production was observed. We also demonstrated that total PC (tPC; a heterogeneous species of PC from egg) and DPPC but not PAPC significantly inhibited the release of TNF-alpha from MM6 cells (P < 0.05). DPPC did not inhibit phosphorylation of the mitogen activated protein kinases (MAPKs) p44/p42 or p38 in stimulated cells. Measurements of membrane fluidity with spin label EPR spectroscopy indicate that DPPC incorporation significantly alters the membrane fluidity of MM6 cells. These results suggest that DPPC, the major component of pulmonary surfactant, may play a role in modulating leucocyte inflammatory responses in the lung. This may in part be related to membrane effects but does not include alterations in p44/p42 or p38 MAPK signalling.

1,2-Dipalmitoylphosphatidylcholine↗
PubMed2000

Seasonal variation in interleukin 4 in patients with hayfever.

This study was performed to investigate the value of interleukin 4 as a marker of activity in mild atopic disease. We compared IL-4 levels to eosinophil cationic protein (ECP), a suggested inflammatory marker in allergic disease, in patients with hayfever. Patients with hayfever were assessed during January and then in late June at the height of the grass pollen season, and their levels of serum ECP and IL-4 compared. Serum ECP was determined by radio-immunoassay and serum IL-4 by a high-sensitivity enzyme-linked immunosorbent assay. ECP was found to increase significantly in patients with hayfever during the grass pollen season (P<0.01). Conversely, serum levels of IL-4 were found to decrease significantly over the same period when compared with winter values. ECP and IL-4 were not seen to correlate significantly with each other. The fall in serum IL-4 seen during the grass pollen season in the hayfever patients may reflect allergen driven upregulation of membrane IL-4 receptor expression or sequestration of cytokine producing cells to inflammatory sites. These findings suggest that serum IL-4 is a poor indicator of inflammatory status in allergic disease.

Blood Proteins↗
PubMed2000

Prostaglandin E(2) and tumour necrosis factor-alpha release by monocytes are modulated by phospholipids.

The regulation of pro- and anti-mediator release from cells within the alveolar space would represent a desirable mechanism serving to protect this delicate gas-exchanging region of the lung. This study investigates the effect of alveolar surfactant lipids on the regulation of tumour necrosis factor alpha (TNF-alpha), a potent inflammatory cytokine, and prostaglandin E(2)(PGE(2)), a lipid mediator with anti-inflammatory properties. The results of this investigation reveal a marked effect on the release of these two important mediators from a monocytic cell line, MonoMac 6 (MM6), by phosphatidylcholine (PC), phosphatidylethanolamine (PE), cholesterol (Chol) and sphingomyelin (SM). PC, PE and Chol demonstrated marked downregulation of TNF-alpha production at lipid concentrations of 125 and 250 microg/ml. Interestingly, SM significantly up regulated the release of TNF-alpha at these concentrations. However, the release of PGE(2)in MM6 cells incubated with the same lipids was significantly increased with PC and Chol, and significantly decreased in cells pre-treated with SM. This indicates a role for these lipids in alveolar immunoregulation.

Cell Line↗
PubMed2000

Demographic characteristics and primary health care utilization patterns of strictly orthodox Jewish and non-Jewish patients.

BACKGROUND: The importance of providing health care services that are acceptable to different cultural groups is widely acknowledged. Strictly orthodox Jewish communities have particular health care needs that reflect their religious teaching and beliefs. OBJECTIVE: To describe the demographic characteristics and health care usage patterns of the strictly orthodox Jewish population of Gateshead. METHODS: Registration and claims data were used in combination with encounter data from computerized and manual practice records. Jewish patients were identified and comparisons made between Jewish and non-Jewish populations registered at the same practices. RESULTS: The orthodox Jewish population was predominantly young (69% aged under 20). The birth rate in orthodox Jewish women aged 20-44 was much higher (294 per 1000) than non-Jewish women. Rates of uptake of cervical screening and childhood immunizations were significantly lower in the orthodox Jewish population. Uptake of breast screening and attendance at diabetic clinics did not differ significantly. The average number of consultations and home visits per annum was higher in Jewish than in non-Jewish patients. CONCLUSIONS: The demographic and health care utilization patterns of orthodox Jewish and non-Jewish patients in Gateshead are different. There are implications for the provision of primary care services, particularly with regard to preventative health care.

Adolescent↗
PubMed1999

Oral contraception: current use and attitudes.

Oral contraception (OC) has been available for almost four decades. During this time, changes in contraceptive use in general and OC in particular have occurred. Knowledge and attitudes about OC may not always reflect trends in use. Contraceptive use data from 1965-1995 show that OC continue to be the method chosen consistently by more than one-quarter of women contraceptors. Probably even more women would use the pill if they had more accurate information regarding the higher failure rates with barrier methods (especially the condom), if misperceptions about OC safety were put to rest, and if greater awareness of the noncontraceptive health benefits of OC could be achieved. Increased education and awareness of women as well as their healthcare providers has the potential to positively affect future contraceptive use.

Breast Neoplasms↗
PubMed1999

A simplified coculture system using homologous, attached cumulus tissue results in improved human embryo morphology and pregnancy rates during in vitro fertilization.

PURPOSE: This study was undertaken to evaluate simplified methods of human embryo coculture using either attached or nonattached autologous cumulus tissue. METHODS: Eight hundred one zygotes were cultured for 48 hr in a prospective, randomized trial comparing culture of embryos either with intact cumulus tissue, with cumulus tissue added to the droplet of culture medium, or without any cumulus tissue. In a follow-up study, embryo quality, pregnancy rates, and implantation rates were compared in 120 consecutive patients undergoing in vitro fertilization with a coculture system using cumulus tissue compared to a cohort of 127 patients undergoing IVF immediately preceding the institution of the coculture protocol. RESULTS: Embryo morphology was significantly improved (P < 0.05) following culture with attached cumulus tissue (5.61 +/- 0.29) and culture with added cumulus tissue (4.72 +/- 0.31) compared to that of embryos grown in culture medium without cumulus tissue (3.95 +/- 0.26). The clinical pregnancy rate improved from 39.4% (50/127) to 49.2% (59/120) following institution of a system of coculture with attached cumulus tissue. CONCLUSIONS: These data indicate that a simple coculture system using autologous cumulus tissue can result in improved embryo morphology, implantation rates, and clinical pregnancy rates during in vitro fertilization. This coculture system is simple, is non-labor intensive, and eliminates many of the risks which may be present in other embryo coculture systems.

Cell Culture Techniques↗
PubMed1999

Self-treatment of asthma: possibilities and perspectives from the practitioner's point of view.

OBJECTIVES: Self-management of asthma is becoming more and more widespread. The implementation of this treatment strategy requires changes in the role and attitude of the GP. These changes may be hindered by obstacles both expected and experienced. As self-treatment of asthma is more common in the UK, comparison between UK and Dutch GPs provides a good opportunity to identify possible obstacles in general practice to the implementation of self-treatment of asthma with inhaled corticosteroids. METHODS: We carried out a qualitative descriptive study with self-administered questionnaires and interviews. Questionnaires were sent to 500 randomly selected Dutch GPs. Interviews were held with 20 Dutch and 25 British GPs in order to acquire more in-depth information. The outcome measures were attitude towards, knowledge regarding and experiences with self-treatment of asthma; organizational requirements; and expectations of consequences of self-treatment in general practice. RESULTS: The Dutch and British GPs investigated have a positive attitude towards self-treatment of asthma. Though knowledge about self-treatment is present among a majority of the GPs, self-treatment by patients is not yet as common in The Netherlands as it is in the UK. Nineteen per cent of the Dutch GPs had experience with a written peak-flow-based self-treatment plan related to the usage of inhaled steroids. According to our findings, present expected obstacles are probably mainly of the organizational kind, such as the availability of time, money and materials. CONCLUSIONS: There is a positive attitude towards the implementation of self-treatment plans in general practice, but problems relating to certain identified obstacles need to be addressed. There is a need to define which patients might profit from self-treatment, and further proof of both the clinical effectiveness and the cost-effectiveness of self-treatment needs to be acquired.

Administration, Inhalation↗
PubMed1998

A randomized, prospective analysis of five sperm preparation techniques before intrauterine insemination of husband sperm.

OBJECTIVE: To evaluate pregnancy rates (PRs) in women undergoing artificial insemination with sperm alternately prepared by one of five techniques: sperm washing, Percoll gradient centrifugation, swim-up, swim-down, or refrigeration/heparin treatment. DESIGN: Each treatment group alternated in a different order through the five sperm preparations. Pregnancy rates were compared for each sperm preparation. SETTING: Two infertility centers, one located in an academic institution and the other a regional hospital. PATIENT(S): Three hundred sixty-three women undergoing 898 artificial inseminations with husband semen with a progressive motile sperm count of >20 million sperm per mL were randomly placed in the five treatment groups. MAIN OUTCOME MEASURE(S): Pregnancy rates. RESULT(S): The overall ongoing PR per insemination was 9.7% (87/898), including 6.12% for natural cycles (n = 196), 12.8% for clomiphene citrate-stimulated cycles (n = 101), and 10.3% for gonadotropin-stimulated cycles (n = 601). The highest ongoing PRs for sperm preparations followed the swim-up technique (13.2%, 26/197) and the Percoll gradient centrifugation technique (12.7%, 26/204). CONCLUSION(S): These data suggest that the swim-up and Percoll gradient preparations result in higher PRs than the wash, swim-down, and refrigeration/heparin techniques.

Centrifugation, Density Gradient↗