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Summary Human natural killer (NK) cells play an important role in anti-viral immunity. However, studying their activation kinetics during infection is highly problematic. A clinical trial of a therapeutic virus provided an opportunity to study human NK cell activation in vivo in a controlled manner. Ten colorectal cancer patients with liver metastases received between one and five doses of oncolytic reovirus prior to surgical resection of their tumour. NK cell surface expression of the interferon-inducible molecules CD69 and tetherin peaked 24–48 h post-infection, coincident with a peak of interferon-induced gene expression. The interferon response and NK cell activation were transient, declining by 96 h post-infection. Furthermore, neither NK cell activation nor the interferon response were sustained in patients undergoing multiple rounds of virus treatment. These results show that reovirus modulates human NK cell activity in vivo and suggest that this may contribute to any therapeutic effect of this oncolytic virus. Detection of a single, transient peak of activation, despite multiple treatment rounds, has implications for the design of reovirus-based therapy. Furthermore, our results suggest the existence of a post-infection refractory period when the interferon response and NK cell activation are blunted. This refractory period has been observed previously in animal models and may underlie the enhanced susceptibility to secondary infections that is seen following viral infection.

Apoptosis leads to the fragmentation and packaging of cellular contents into discrete vesicles, a process known as 'blebbing'. Extracellular vesicles express membrane-bound sialic acids, which enable their capture by CD169 (sialoadhesin; Siglec-1) expressing macrophages in the lymph node and spleen. Furthermore, CD169 mediates vesicle trafficking and suppresses the immune response to exosomes-a type of extracellular vesicle released from living cells. In this study, we found that CD169(+) macrophages were the predominant splenic macrophage subset responsible for the capture of EL4 lymphoma-derived apoptotic vesicles (ApoVs) from circulation. CD169(-/-) mice had significantly enhanced in vivo cytotoxic T lymphocyte responses to antigen-pulsed ApoVs, indicating a suppressive role for CD169(+) macrophages to ApoV-associated antigen. In contrast to the observed immunogenic role of ApoVs, the co-administration of unpulsed ApoVs with antigen-pulsed dendritic cells (DCs) significantly suppressed DC-mediated cytotoxic response in vivo; however, this occurred independent of CD169 expression. Overall, our results confirm that apoptosis contributes to both tolerance and immunity, as well as establishing CD169 as a critical mediator of the immune response to extracellular vesicles.

Interactions between natural killer (NK) cells and dendritic cells (DCs) aid DC maturation and promote T-cell responses. Here, we have analyzed the response of human NK cells to tumor cells, and we identify a pathway by which NK-DC interactions occur. Gene expression profiling of tumor-responsive NK cells identified the very rapid induction of TNF superfamily member 14 [TNFSF14; also known as homologous to lymphotoxins, exhibits inducible expression, and competes with HSV glycoprotein D for HVEM, a receptor expressed by T lymphocytes (LIGHT)], a cytokine implicated in the enhancement of antitumor responses. TNFSF14 protein expression was induced by three primary mechanisms of NK cell activation, namely, via the engagement of CD16, by the synergistic activity of multiple target cell-sensing NK-cell activation receptors, and by the cytokines IL-2 and IL-15. For antitumor responses, TNFSF14 was preferentially produced by the licensed NK-cell population, defined by the expression of inhibitory receptors specific for self-MHC class I molecules. In contrast, IL-2 and IL-15 treatment induced TNFSF14 production by both licensed and unlicensed NK cells, reflecting the ability of proinflammatory conditions to override the licensing mechanism. Importantly, both tumor- and cytokine-activated NK cells induced DC maturation in a TNFSF14-dependent manner. The coupling of TNFSF14 production to tumor-sensing NK-cell activation receptors links the tumor immune surveillance function of NK cells to DC maturation and adaptive immunity. Furthermore, regulation by NK cell licensing helps to safeguard against TNFSF14 production in response to healthy tissues.

Summary 421 I. INTRODUCTION 421 II. EFFECTS OF OZONE ON REPRODUCTION 423 1. Pollen germination and pollen tube growth 424 2. Floral initiation and development 428 3. Effects on seed and fruit yield and yield components 433 4. Effects of ozone on seed and fruit quality, germination and seedling growth 437 III. INFLUENCE OF REPRODUCTIVE HABIT AND IMPLICATIONS FOR FIELD-GROWN PLANTS 438 IV. CONCLUSIONS AND FUTURE RESEARCH 441 Acknowledgements 442 References 442 Sexual reproductive development is a crucial stage in the life cycle of higher plants as any impairment of the processes involved might have significant implications for the productivity of crop plants and the survival of native species. There is considerable evidence that exposure to ozone, even at current ambient levels in many industrialized countries, reduces grain and fruit yields and adversely affects yield quality. It is also well established that sensitivity to ozone may differ not only between species, but also between cultivars and populations of individual species, and that the impact of exposure is highly dependent on ozone concentration and the duration and timing of exposure. However, few studies have attempted to distinguish between the direct effects of air pollutants on reproductive development, and indirect effects mediated by injury to the vegetative organs and associated changes in the supply of assimilates and other essential resources to support reproductive growth, or the levels of endogenous growth regulators. This review considers the impact of ozone on the reproductive biology of agricultural and native species, and examines its direct effects on specific reproductive processes. The extent to which compensatory responses redress the adverse effects of exposure is also explored, with particular reference to recent studies of Brassica napus (oilseed rape), Brassica campestris (Wisconsin Fast Plants), Plantago major (greater plantain) and Triticum aestivum (wheat).

Adrenal androgen (AA) excess, primarily in the form of dehydroepiandrosterone sulfate (DHEAS), affects over 50% of women with the polycystic ovary syndrome (PCOS). Nonetheless, it is unclear what role AA excess plays in the PCOS-associated oligo-ovulation. We have hypothesized that AAs are important in the maintenance of the ovulatory dysfunction of women with PCOS and AA excess, which can be improved by glucocorticoid suppression. To test our hypothesis we prospectively studied 36 unselected women, ages 18-40 yr, with PCOS; i.e. oligomenorrhea (cycles > 35 days in length), and clinical/ biochemical evidence of hyperandrogenism (i.e. hirsutism and/or hyperandrogenemia), after the exclusion of related disorders. After informed consent, all patients underwent an acute ACTH-(1-24) stimulation test, measuring androstenedione, dehydroepiandrosterone (DHEA) and cortisol (F), and were then treated with dexamethasone 0.5 mg/day for four cycles. Ovulatory function was assessed before and during treatment using a basal body temperature calendar and day 22-24 progesterone (P4) levels. If patients were anovulatory (P4 4 ng/mL); and of the remaining, 10 (28%) had only one, five (14%) had two, and three (8%) had three ovulatory cycles. There were no significant differences either in physical features, basal hormones, adrenal response to ACTH stimulation, or hormonal levels at the end of treatment, between those women ovulating and those not. Finally, there were no differences in ovulatory response to dexamethasone therapy between women with (n = 14) and without (n = 22) DHEAS excess (i.e. DHEAS > 2750 ng/mL). In conclusion, the data from this prospective study do not suggest that continuous dexamethasone suppression results in consistent ovulation in any PCOS patient, regardless of basal DHEAS levels. Furthermore, this treatment is associated with significant side-effects, notably weight gain. Finally, these data suggest that, while AA may be an important risk factor for PCOS, once the syndrome is established, they play a limited role in the associated ovulatory dysfunction.

Over 50% of patients with the polycystic ovary syndrome (PCOS) demonstrate excess levels of adrenal androgens (AAs), particularly dehydroepiandrosterone sulfate (DHS). Nonetheless, the mechanism for the AA excess remains unclear. It has been noted that in PCOS the pituitary and ovarian responses to their respective trophic factors (i.e. GnRH and LH, respectively) are exaggerated. Similarly, we have postulated that excess AAs in PCOS arises from dysfunction of the hypothalamic-pituitary-adrenal axis, due to 1) exaggerated pituitary secretion of ACTH in response to hypothalamic CRH, 2) excess sensitivity/responsivity of AAs to ACTH stimulation, or 3) both. To test this hypothesis we studied 12 PCOS patients with AA excess (HI-DHS; DHS, >8.1 μmol/L or 3000 ng/mL), 12 PCOS patients without AA excess (LO-DHS; DHS

SUMMARY A single exposure of pollen of Brassica napus L. cvs Tapidor or Libravo to 100 nl l−1 ozone (O3) either in vitro or in vivo on the anthers of intact plants had no significant effect on either pollen germination or pollen tube growth. Exposure of dry pollen to 200 nl l−1 sulphur dioxide (SO2) also produced no significant effect. However, pollen germination was significantly reduced and pollen tube growth impaired in both cultivars when pollen was exposed in unbuffered incubation medium to 200 nl l−1 SO2. The pH of the unbuffered medium fell from 6.5 to 5.5 during fumigation, suggesting a role for acidification in the observed SO2-induced effects. This view is supported by evidence that percentage germination decreased linearly with pH in culture media buffered to provide pH values ranging from 6.05 to 3.0. Pollen tube growth was also impaired at pHs of 5.6 and below. The significance of pollutant-induced impairment of pollen germination and growth for reproductive development and the influence of moisture in modifying the impact of SO2 and O3 are discussed.

Twenty term/near term neonates with hypoxemic respiratory failure and oxygenation index >/=20 were enrolled in a Phase I/II feasibility, safety and dose escalation study of inhaled PGE(1) (IPGE(1)). Incremental doses of IPGE(1), delivered by a jet nebulizer over a 2-h period, followed by weaning over 1 h, were given to 13 patients before receiving inhaled nitric oxide (INO) (Group I), and to seven patients, who failed to respond to INO (Group II). Response was defined as an increase in P(a)O(2) of either >/= 25 (full) or 10-25 (partial) torr. Exit criteria included an acute deterioration in oxygenation status, a persistent oxygenation index above 35 in Group I, or the availability of extracorporeal membrane oxygenation (ECMO) in Group II. The mean (SD) increase in P(a)O(2) at the end of IPGE(1) administration was 63 (62.3) in Group I (p = 0.024), and 40 (62.1) in Group II (p > 0.05). In Group I, 8 of 13 neonates had a full response, but 4 deteriorated following discontinuation of IPGE(1). Of these four, two responded to INO and two were placed on ECMO. Five patients deteriorated before or during IPGE(1,) and none of them responded to INO. In Group II, three of seven patients had a full response to IPGE(1). One patient with a partial response and all patients exiting before or during IPGE(1) administration were placed on ECMO. The results of our study indicate that IPGE(1) may be a safe, selective pulmonary vasodilator in neonatal hypoxemic respiratory failure.

Adrenal androgen (AA) excess, primarily in the form of dehydroepiandrosterone sulfate (DHEAS), affects over 50% of women with the polycystic ovary syndrome (PCOS). Nonetheless, it is unclear what role AA excess plays in the PCOS-associated oligo-ovulation. We have hypothesized that AAs are important in the maintenance of the ovulatory dysfunction of women with PCOS and AA excess, which can be improved by glucocorticoid suppression. To test our hypothesis we prospectively studied 36 unselected women, ages 18-40 yr, with PCOS; i.e. oligomenorrhea (cycles > 35 days in length), and clinical/ biochemical evidence of hyperandrogenism (i.e. hirsutism and/or hyperandrogenemia), after the exclusion of related disorders. After informed consent, all patients underwent an acute ACTH-(1-24) stimulation test, measuring androstenedione, dehydroepiandrosterone (DHEA) and cortisol (F), and were then treated with dexamethasone 0.5 mg/day for four cycles. Ovulatory function was assessed before and during treatment using a basal body temperature calendar and day 22-24 progesterone (P4) levels. If patients were anovulatory (P4 4 ng/mL); and of the remaining, 10 (28%) had only one, five (14%) had two, and three (8%) had three ovulatory cycles. There were no significant differences either in physical features, basal hormones, adrenal response to ACTH stimulation, or hormonal levels at the end of treatment, between those women ovulating and those not. Finally, there were no differences in ovulatory response to dexamethasone therapy between women with (n = 14) and without (n = 22) DHEAS excess (i.e. DHEAS > 2750 ng/mL). In conclusion, the data from this prospective study do not suggest that continuous dexamethasone suppression results in consistent ovulation in any PCOS patient, regardless of basal DHEAS levels. Furthermore, this treatment is associated with significant side-effects, notably weight gain. Finally, these data suggest that, while AA may be an important risk factor for PCOS, once the syndrome is established, they play a limited role in the associated ovulatory dysfunction.

Background: Exposure to violence in childhood has been associated with lower school grades. However, the association between violence exposure and performance on standardized tests (such as IQ or academic achievement) in children is unknown. It is also not known whether violence exposure itself or subsequent symptoms of trauma are primarily responsible for negative outcomes. Objective: To examine the relationship between violence exposure and trauma-related distress and standardized test performance among early school-aged urban children, controlling for important potential confounders. Design: A total of 299 urban first-grade children and their caregivers were evaluated using self-report, interview, and standardized tests. Main Outcome Measures: The child’s IQ (Wechsler Preschool and Primary Scale of Intelligence–Revised) and reading ability (Test of Early Reading Ability, second edition) were the outcomes of interest. Results: After controlling for confounders (child’s gender, caregiver’s IQ, home environment, socioeconomic status, and prenatal exposure to substance abuse) violence exposure was related to the child’s IQ (P=.01) and reading ability (P=.045). Trauma-related distress accounted for additional variance in reading ability (P=.01). Using the derived regression equation to estimate effect sizes, a child experiencing both violence exposure and trauma-related distress at or above the 90th percentile would be expected to have a 7.5-point (SD, 0.5) decrement in IQ and a 9.8point (SD, 0.66) decrement in reading achievement. Conclusion: In this study, exposure to violence and trauma-related distress in young children were associated with substantial decrements in IQ and reading achievement.

This paper reports a quick, relatively simple and reproducible technique for obtaining populations of zona fasciculata and zona glomerulosa cells up to 80-90% pure, which can be maintained in vitro for study of adrenocortical cell function. Isolated guinea pig adrenocortical cells were separated on a 1-28% bovine serum albumin/Ca++, Mg++-free buffer gradient (wt/vol at 4% increments) using equilibrium density centrifugation (570 g, 30 min). Over 60% of the 8 x 10(5) viable cells/adrenal obtained in the total isolate were recovered after separation. 80% of the zona glomerulosa cells were found in the lower three bands of the gradient. 78% of the zona fasciculata cells were found in the top three bands. Of the cells in the first two bands, 78-91% were zona fasciculata cells, whereas of the cells in the bottom two bands 92-95% were zona glomerulosa cells. The cells retained the morphological characteristics of cells in situ and could be maintained in vitro for periods up to 11 d. They produced a wide variety of steroids, cortisol, corticosterone, aldosterone, 11-beta-hydroxyandrostenedione, deoxycortisol, deoxycorticosterone, cortisone, 18-hydroxycorticosterone, and a product tentatively identified as dehydroepiandrosterone, and they responded to ACTH in a dose-responsive manner with enhanced levels of steroid output. Zona glomerulosa-enriched populations differed from zona fasciculata-enriched populations in their abundant production of aldosterone and in the pattern of steroid production. None of the cultures responded to angiotensin II (100 pg/ml) with increased steroid production.

In most laboratory investigations of plant responses to air pollution, plants are exposed to a single pollutant gas. However, in rural atmospheres, pollutants seldom occur singly; for example, in central England, where summertime mean concentrations of sulphur dioxide are typically 10–30 p.p.b. (parts in 109 by volume) depending on the site, there are 10–30 days each summer when concentrations of ozone generated photo-chemically exceed 80 p.p.b. for at least 1 h (ref. 1). Maximum hourly ozone concentrations of 130–260 p.p.b. have been reported1–3. Similarly, maximum hourly SO2 concentrations in rural central England exceed 50 p.p.b. for a few hours each month. We have previously shown4 that net photosynthetic rates PN of field beans, Vicia faba L. c.v. Dylan, were depressed, in comparison with rates in clean air, on exposure to SO2 concentrations as low as 40 p.p.b. Responses of photosynthesis to mixtures of SO2 and O3 seem to have been studied only at higher concentrations atypical of the natural environment5,6. We report here that the addition of ozone in the concentration range 60–150 p.p.b. to atmospheres containing 40 p.p.b. SO2 led to decreases in PN of V. faba L. larger than those observed in either gas alone.