Ox40-ligand has a critical costimulatory role in dendritic cell:T cell interactions

The tumor necrosis factor family molecule Ox40-ligand (Ox40L) has been identified as a potential costimulatory molecule and also has been implicated in T cell homing and B cell activation. To ascertain the essential functions of Ox40L, we generated and characterized Ox40L-deficient mice. Mice lacking Ox40L exhibit an impaired contact hypersensitivity response, a dendritic cell-dependent T cell-mediated response, due to defects in T cell priming and cytokine production. In contrast, Ox40L-deficient mice do not have defects in T cell homing or humoral immune responses. In vitro, Ox40L-deficient dendritic cells are defective in costimulating T cell cytokine production. Thus, Ox40L has a critical costimulatory function in vitro and in vivo for dendritic cell:T cell interactions.

Synergistic operation of the CAR2 (Ornithine transaminase) promoter elements in Saccharomyces cerevisiae

Dal82p binds to the UIS(ALL) sites of allophanate-induced genes of the allantoin-degradative pathway and functions synergistically with the GATA family Gln3p and Gat1p transcriptional activators that are responsible for nitrogen catabolite repression-sensitive gene expression. CAR2, which encodes the arginine-degradative enzyme ornithine transaminase, is not nitrogen catabolite repression sensitive, but its expression can be modestly induced by the allantoin pathway inducer. The dominant activators of CAR2 transcription have been thought to be the ArgR and Mcm1 factors, which mediate arginine-dependent induction. These observations prompted us to investigate the structure of the CAR2 promoter with the objectives of determining whether other transcription factors were required for CAR2 expression and, if so, of ascertaining their relative contributions to CAR2's expression and control. We show that Rap1p binds upstream of CAR2 and plays a central role in its induced expression irrespective of whether the inducer is arginine or the allantoin pathway inducer analogue oxalurate (OXLU). Our data also explain the early report that ornithine transaminase production is induced when cells are grown with urea. OXLU induction derives from the Dal82p binding site, which is immediately downstream of the Rap1p site, and Dal82p functions synergistically with Rap1p. This synergism is unlike all other known instances of Dal82p synergism, namely, that with the GATA family transcription activators Gln3p and Gat1p, which occurs only in the presence of an inducer. The observations reported suggest that CAR2 gene expression results from strong constitutive transcriptional activation mediated by Rap1p and Dal82p being balanced by the down regulation of an equally strong transcriptional repressor, Ume6p. This balance is then tipped in the direction of expression by the presence of the inducer. The formal structure of the CAR2 promoter and its operation closely follow the model proposed for CAR1.

Nutrition, fertility and steady-state population dynamics in a pre-industrial community in Penrith, northern England

The effect of nutrition on fertility and its contribution thereby to population dynamics are assessed in three social groups (elite, tradesmen and subsistence) in a marginal, pre-industrial population in northern England. This community was particularly susceptible to fluctuations in the price of grains, which formed their basic foodstuff. The subsistence class, who formed the largest part of the population, had low levels of fertility and small family sizes, but women from all social groups had a characteristic and marked subfecundity in the early part of their reproductive lives. The health and nutrition of the mother during pregnancy was the most important factor in determining fertility and neonatal mortality. Inadequate nutrition had many subtle effects on reproduction which interacted to produce a complex web of events. A population boom occurred during the second half of the 18th century; fertility did not change but there was a marked improvement in infant mortality and it is suggested that the steadily improving nutritional standards of the population, particularly during crucial periods in pregnancy (i.e. the last trimester), probably made the biggest contribution to the improvement in infant mortality and so was probably the major factor in triggering the boom.

Low uptake of eye services in rural India: a challenge for programs of blindness prevention

OBJECTIVES

To investigate service uptake in a rural Indian population served by outreach eye camps and to identify barriers to uptake.

PARTICIPANTS AND METHODS

A routine eye camp was conducted within 5 km of each of 48 randomly selected villages of typically Hindu, backward-caste communities. Subsequently, participatory rural appraisal-community mapping, focus groups, matrix ranking, and semistructured interviews-was undertaken to explore community views of eye problems. An eye examination was conducted on persons with eye problems who did not attend the eye camp. Predictors of attendance were identified by multilevel regression analysis.

RESULTS

Of 749 adults with an eye problem, 51 (6.8%) attended the eye camp. Independent predictors of attendance were being male (odds ratio = 2.3; 95% confidence interval, 1.2-4.5) and living within 3 km of the camp (odds ratio = 4.5; 95% confidence interval, 1.7-12.5). Of the 552 persons who did not attend the eye camps and had an eye examination, 242 (43.8%) had low vision (visual acuity <6/18 to > or =3/60 in presenting better eye) and 38 (6.9%) were blind in both eyes. Cataract surgery was recommended for 197 (35.8%) of the persons who did not attend the eye camps. Of 109 persons with a previous cataract operation, 42 (38.5%) had low vision and 11 (10.1%) were blind. Fear (principally of eye damage), cost (direct and indirect), family responsibilities, ageism, fatalism, and an attitude of being able to cope (with low or no vision) were the principal barriers to attending the eye camps.

CONCLUSIONS

A high proportion of people who could have benefited from eye treatment were not using available services. Poor visual outcomes were observed in surgically treated persons.

Breast cancer. Making the diagnosis

The approach to women with breast complaints must be individualized based on the presenting problem, patients' age, and the degree of clinical suspicion. Needle-biopsy, techniques are often cost-effective. In patients with suspicious breast abnormalities, a thorough imaging workup facilitates the selection of definitive local therapy.

Novel inhibitors of advanced glycation endproducts

Enhanced formation and accumulation of advanced glycation endproducts (AGE's) have been proposed to play a major role in the pathogenesis of diabetic complications, aging, atherosclerosis, and Alzheimer disease leading to progressive and irreversible intermolecular protein crosslinkings. This process is accelerated in diabetes and has been postulated to contribute to the development of a range of diabetic complications including nephropathy, retinopathy and neuropathy. Several potential drug candidates as AGE inhibitors have been reported recently. Aminoguanidine is the first drug extensively studied both in vitro and in vivo. We have developed a new class of compounds as potent inhibitors of glycation and AGE formation. The novel inhibitors reported here are aryl (and heterocyclic) ureido, and aryl (and heterocyclic) carboxamido phenoxy isobutyric acids and related molecules, which were found by in vitro assay methods to be potent inhibitors of multiple stage of glycation and AGE formation.

Father sues doctor over right to be told of alternative therapy for child's brain tumor

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A novel four-drug ablative regimen with hemopoietic stem cell rescue for patients with breast cancer: a phase II study

High-dose chemotherapy and autologous hemopoietic stem cell transplantation (HSCT) may provide durable progression-free survival in some patients with stage IV breast cancer (S4Brca). We have studied a new four-drug intensive preparative regimen with HSCT in a group of 158 women with S4Brca to define the risk and potential benefit of this regimen in this patient population. From May 1988 through May 1997, 158 women with S4Brca at a single center were treated with cisplatin, etoposide, thiotepa, and cyclophosphamide (PETCy) plus autologous HSCT Eligible patients were also treated with posttransplant involved-field radiation therapy. Patients with estrogen-receptor positive tumors not previously treated with tamoxifen also received this therapy for 5 years following transplantation. All patients experienced significant toxicity requiring blood-product support and parenteral nutrition. Eighteen patients (11%) died of regimen-related toxic events. With a median follow-up of 540 days for surviving patients, a retrospective Kaplan-Meier analysis projects an overall survival of 38+/-8.5% (95% CI) at 890 days with a maximum follow-up of 8.8 years. For 52 patients in sensitive relapse, the median event-free survival time is 767 days, with 46.2+/-15.3% (95% CI) predicted to be alive at 884 days with a maximal follow-up of almost 9 years. Nearly one-half of patients in this study with S4Brca in sensitive relapse have experienced durable remissions following PETCy ablation and HSCT. Although toxicity is significant, the PETCy regimen produces a favorable balance between efficacy (event-free survival) and treatment failure (relapse + regimen-related toxic death) compared with published results. These data suggest that within the high-dose range for preparative therapy, a steep dose-response may exist for breast cancer. Trials comparing the dose intensity of preparative regimens are warranted.

Automated malaria detection by depolarization of laser light

Anecdotal experience with full blood count (FBC) technology incorporating analysis of depolarized laser light (DLL) for the enumeration of eosinophils showed that malaria infection generated unusual distributions in the white cell channels. The objective of this study was to identify and define criteria for a diagnosis of malaria using this technology. To determine sensitivity, specificity, and positive and negative predictive values, 224 directed samples referred specifically for malaria were used; true positives were defined as those in which malaria was identified by microscopic and/or immunological methods. For the DLL method, positive was defined as one or more large mononuclear cell(s) for which the 90 degrees depolarized signal exceeded the 90 degrees polarized signal. To determine possible utility in a routine haematology laboratory setting, 220 random undirected FBC samples were evaluated for possible malaria infection by the DLL method. Of the 224 directed samples, 95 were malaria positive as determined by microscopic and/or immunological methods, and 129 were negative. For the DLL method, overall sensitivity was 72% (90% in the case of Black Africans), and specificity 96%. Positive and negative predictive values overall were 93% and 82% respectively. In the utility study a single positive result was identified among the 220 samples studied. This was found to be from a patient with malaria. The detection of unexpected malaria by automated screening FBC analysis could substantially lower the mortality and morbidity from unascertained infection, especially in indigenous African peoples.

Mild illness at or after measles vaccination does not reduce seroresponse in young children

We analyzed data from a randomized trial of AIK-C, high-titre (EZ-H) or medium-titre EZ (EZ-M) vaccines in 3.5 and 6 month old infants in Kinshasa, Zaire, in which the occurrence of rhinorrhoea, cough, diarrhoea, fever, conjunctivitis or rash was monitored for 15 days post-vaccination (including the day of vaccination, day 0). We compared sero-response at 6 weeks and 6 months post-vaccination among children with and without mild illness at or after vaccination. Seroresponse tended to be higher in children with mild illness after vaccination than those without, whether days 0-7 or 8-15 were examined. For most symptoms, these differences did not reach statistical significance after adjusting for prevaccination maternal antibody level. However, in the EZ-M group, the proportion of children attaining at least the median post-vaccination antibody level was significantly higher in children with rhinorrhoea in days 0-7 post-vaccination than those without (adjusted odds ratio 2.6, 95% CI 1.08-6.27), as was that among children with at least one symptom in days 0-7 compared with children with no symptoms (adjusted OR 4.55, 95% CI 1.18-17.57). There were no significant differences in post-vaccination antibody levels among children with symptoms compared either to those without the specific symptom or those with no symptoms. Fever on the day of vaccination or at home visits on 7, 10 or 14 days post-vaccination, did not affect seroconversion or GMTs. Regression models showed no relation between the cumulative number of days with symptoms and antibody increase after vaccination. Analysis of antibody levels at 6 months post-vaccination showed no consistent differences according to presence or absence of symptoms. These findings provide further strong support to recommendations that mild illness is not a reason to delay measles vaccination.

Comparing the Strengths and Difficulties Questionnaire and the Child Behavior Checklist: is small beautiful?

The Strengths and Difficulties Questionnaire (SDQ) is a brief behavioral screening questionnaire that can be completed in 5 minutes by the parents or teachers of children aged 4 to 16; there is a self-report version for 11- to 16-year-olds. In this study, mothers completed the SDQ and the Child Behavior Checklist (CBCL) on 132 children aged 4 through 7 and drawn from psychiatric and dental clinics. Scores from the SDQ and CBCL were highly correlated and equally able to discriminate psychiatric from dental cases. As judged against a semistructured interview, the SDQ was significantly better than the CBCL at detecting inattention and hyperactivity, and at least as good at detecting internalizing and externalizing problems. Mothers of low-risk children were twice as likely to prefer the SDQ.

Development of a dual glow-signal firefly and Renilla luciferase assay reagent for the analysis of G-protein coupled receptor signalling

Several reporter gene assays have been described where gene transcription is activated as a consequence of a specific signal transduction event, such as activation of adenylyl cyclase (1.2). Reporter genes typically consist of specific responsive elements placed upstream of a minimal promoter, which together control the expression of a readily detectable reporter protein, such as luciferase. We have developed a dual glow-signal firefly and Renilla luciferase assay, which allows the simultaneous measurement of two reporter genes in the same well of a 96-well plate. In this report we demonstrate the use of this assay for the simultaneous analysis of agonist activity at two G-protein coupled receptors which signal through activation of the G-protein alpha sub-unit, G alpha S. Chinese hamster ovary (CHO) cells stably transfected with a cAMP responsive firefly luciferase reporter were further transfected with the human Vasopressin V2 receptor. Similarly, CHO cells stably transfected with a cAMP responsive Renilla luciferase reporter were further transfected with the human beta 2-adrenoceptor. The two cell lines were mixed in individual wells of a 96-well plate and a number of compounds were screened to determine their activity at both receptors. Stimulation with vasopressin and beta 2-adrenoceptor agonists resulted in the activation of the firefly and Renilla luciferases respectively. Stimulation with forskolin, which directly stimulates adenylyl cyclase, caused the activation of both reporter genes, and stimulation with a range of further compounds with no activity at either receptor did not generate a reporter response. The dual luciferase assay allows the simultaneous screening of two receptors in a 96-well format resulting in significant time and cost savings.

Angiotensin II signaling in vascular smooth muscle cells under high glucose conditions

The mechanisms responsible for the accelerated cardiovascular disease in diabetes, as well as the increased hypertrophic effects of angiotensin II (Ang II) under hyperglycemic conditions, are not very clear. We examined whether the culture of vascular smooth muscle cells (VSMC) under hyperglycemic conditions to simulate the diabetic state can lead to increased activation of key growth- and stress-related kinases, such as the mitogen-activated protein kinases (MAPKs), in the basal state and in response to Ang II. Treatment of porcine VSMC for short time periods (0.5 to 3 hours) with high glucose (HG; 25 mmol/L) markedly increased the activation of the extracellular signal-regulated kinase (ERK1/2) and c-Jun/N-terminal kinase (JNK) relative to cells cultured in normal glucose (NG; 5.5 mmol/L). p38 MAPK also was activated by HG, and this effect remained sustained for several hours. Ang II treatment increased the activity of all 3 families of MAPKs. Ang II-induced ERK activation was potentiated nearly 2-fold in cells treated with HG for 0.5 hour. However, Ang II-induced JNK was not altered. In VSMC cultured for 24 hours with HG, Ang II and HG displayed an additive response on p38 MAPK activity. MAPKs can lead to activation of transcription factors such as activator protein-1 (AP-1). HG alone significantly increased AP-1 DNA-binding activity. Furthermore, Ang II and HG combined had additive effects on AP-1 activity. These results suggest that increased activation of specific MAPKs and downstream transcription factors, such as AP-1, may be key mechanisms for the increased VSMC growth potential of HG alone and of Ang II under HG conditions.

Donor cell induced CD69 expression and intracellular IL-2 and IL-4 production by peripheral blood lymphocytes isolated from kidney transplant recipients

Flow cytometry assays, which measure CD69 activation and intracellular cytokine production, have been used to measure peripheral blood lymphocyte (PBL) responses to in vitro antigen exposure. In the present study, we show that, in healthy individuals and immunosuppressed kidney transplant recipients, CD69 expression and intracellular cytokine production by peripheral blood T cells compare favorably to thymidine uptake as a measure of PBL response to alloantigen in mixed leukocyte culture (MLC). Heparinized whole blood from 23 healthy individuals was incubated for 24-48 h with 3rd party allogeneic monocytes; blood from twelve kidney transplant recipients was incubated with monocytes from their kidney donor and with monocytes from unrelated individuals. The percentage of T cells expressing surface CD69 or intracellular IL-2 or IL-4 was determined by 3-color flow cytometry. We identified 5 donor-specific response patterns in our kidney transplant group. One transplant recipient was hyporesponsive; his cells did not express CD69 or produce IL-2 in response to either donor or 3rd party allogeneic cells. All other transplant recipients expressed CD69 and IL-2 in response to 3rd party allogeneic cells. Two had no response to donor cells (donor-specific hyporesponsiveness), three had donor-specific anergy (CD69 expression without cytokine production in response to donor cells), five had a donor-specific Thl response (CD69 expression and IL-2 production in response to donor cells), and one had a donor-specific Th2 response (CD69 expression and IL-4 but not IL-2 production in response to donor cells). Rapid measures of donor-specific hyporesponsiveness such as CD69 activation antigen expression and intracellular cytokine production may prove valuable in monitoring lymphocyte function and aid in the long-term management of kidney transplant recipients.

ATM associates with and phosphorylates p53: mapping the region of interaction

The human genetic disorder ataxia-telangiectasia (AT) is characterized by immunodeficiency, progressive cerebellar ataxia, radiosensitivity, cell cycle checkpoint defects and cancer predisposition. The gene mutated in this syndrome, ATM (for AT mutated), encodes a protein containing a phosphatidyl-inositol 3-kinase (PI-3 kinase)-like domain. ATM also contains a proline-rich region and a leucine zipper, both of which implicate this protein in signal transduction. The proline-rich region has been shown to bind to the SH3 domain of c-Abl, which facilitates its phosphorylation and activation by ATM. Previous results have demonstrated that AT cells are defective in the G1/S checkpoint activated after radiation damage and that this defect is attributable to a defective p53 signal transduction pathway. We report here direct interaction between ATM and p53 involving two regions in ATM, one at the amino terminus and the other at the carboxy terminus, corresponding to the PI-3 kinase domain. Recombinant ATM protein phosphorylates p53 on serine 15 near the N terminus. Furthermore, ectopic expression of ATM in AT cells restores normal ionizing radiation (IR)-induced phosphorylation of p53, whereas expression of ATM antisense RNA in control cells abrogates the rapid IR-induced phosphorylation of p53 on serine 15. These results demonstrate that ATM can bind p53 directly and is responsible for its serine 15 phosphorylation, thereby contributing to the activation and stabilization of p53 during the IR-induced DNA damage response.

The effects of population density and malnutrition on the dynamics of whooping cough

Liverpool, a seaport in NW England, suffered severely from lethal infectious diseases in the second half of the 19th century: the population was densely crowded and malnourished and life expectancy was low. Time-series analysis shows that the epidemics of whooping cough (i) had an interepidemic interval of 2.9 years, 1863-85, which lengthened to 3.4 years, 1885-1900 (ii) were strongly coherent with wheat prices (P < 0.001) and (iii) also correlated with cycles of seasonal weather conditions. It is suggested from mathematical modelling that the epidemics in this compromised population were maintained (i.e. the system was driven) by an oscillation of malnutrition and by seasonal weather conditions. A model that incorporates both the dynamics of whooping cough and the demographic characteristics of the population is presented. It has been shown to replicate the dynamics of the epidemics and has been used to predict the changes with time of (i) the force of the infection and (ii) the proportion of those infected with whooping cough who died.

Insulin potentiates platelet-derived growth factor action in vascular smooth muscle cells

Correlative studies have indicated that hyperinsulinemia is present in many individuals with atherosclerosis. Insulin resistance has also been linked to cardiovascular disease. It has proved to be difficult to decipher whether hyperinsulinemia or insulin resistance plays the most important role in the pathogenesis of atherosclerosis and coronary artery disease. In this study, we demonstrate that insulin increases the amount of farnesylated p21Ras in vascular smooth muscle cells (VSMC), thereby augmenting the pool of cellular Ras available for activation by platelet-derived growth factor (PDGF). In VSMC incubated with insulin for 24 h, PDGF's influence on GTP-loading of Ras was significantly increased. Furthermore, in cells preincubated with insulin, PDGF increased thymidine incorporation by 96% as compared with a 44% increase in control cells (a 2-fold increment). Similarly, preincubation of VSMC with insulin increased the ability of PDGF to stimulate gene expression of vascular endothelial growth factor 5- to 8-fold. The potentiating influence of insulin on PDGF action was abrogated in the presence of a farnesyltransferase inhibitor. Thus, the detrimental influence of hyperinsulinemia on the arterial wall may be related to the ability of insulin to augment farnesyltransferase activity and provide greater amounts of farnesylated p21Ras for stimulation by various growth promoting agents.

Towards a psycho-social theoretical framework for sexual health promotion

Numerous interventions have been designed to promote safer sexual behaviour amongst young people. However, relatively few have proved effective, which is, at least partially, due to the lack of development of theoretically based programmes. An understanding of the origins and control of sexual behaviour can be derived from basic social science research. Unless this is applied to the design of behaviour-change programmes they are unlikely to target the most important determinants of young people's sexual behaviour and are, therefore, unlikely to be effective. This paper outlines some of the key theoretical insights which have been drawn upon in the development of a new sex education programme currently being tested in Scottish schools. The theoretical basis is intentionally eclectic, combining social psychological cognitive models with sociological interpretations, since we are not concerned to advance any particular theory but to find which are most useful in promoting sexual health. First, the social influences on sexual behaviour are considered, and then the way in which these translate into individual perceptions and beliefs. Finally, the paper attempts to develop a theoretical understanding of sexual interaction and the social contexts of sexual behaviour.

Nociception activates Elk-1 and Sap1a following expression of the ORL1 receptor in Chinese hamster ovary cells

Nociceptin stimulation of the ORL1 receptor expressed in Chinese hamster ovary (CHO) cells results in the activation of the extracellular signal regulated kinases ERK1 and ERK2. ERK1/ERK2 activation is inhibited by pertussis toxin, the MEK inhibitor PD 98059 and by transient expression of alpha-transducin, indicating that ORL1 up-regulation of these kinases occurs as a consequence of the release of the G-protein betagamma complex following the activation of pertussis-toxin sensitive Galphai-family G-proteins. Using specific reporter genes we demonstrate that the transcription factors Elk-1 and Sapla are activated in a pertussis toxin-sensitive manner as a consequence of ORL1 upregulation of ERK1/ERK2 to induce changes in gene expression. The activation of these transcription factors is also inhibited following treatment with PD 98059 and following coexpression of alpha-transducin.