136. PROGESTERONE RECEPTOR-REGULATED GENES IN THE PREOVULATORY OVARIAN FOLLICLE AND OVIDUCT

Ovulation is a highly regulated and precisely timed reproductive process but the underlying molecular mechanisms are not well understood. Progesterone receptor (PGR) is a transcription factor highly yet transiently expressed in granulosa cells (GCs) of preovulatory follicles; has low expression in cumulus-oocyte-complexes (COCs); and is abundantly expressed in the oviduct. PR–/– mice validate its essential role in ovulation as they are anovulatory, despite normal growth and development of ovarian follicles and oocytes. Our aim was to use microarray to identify differentially expressed genes in GCs, COCs and oviducts from PR–/– and PR+/– mice, specifically genes potentially involved in oocyte release and transport. GCs, COCs and oviducts were collected from 21d-old mice (n = 5; 3 mice/replicate) at 8h post-hCG/44h post-eCG. Extracted RNA samples were hybridized to Affymetrix Mouse Gene 1.0 ST Arrays and post-experiment processing/analysis performed using Partek Genomics Suite. Gene ontology analysis was performed using Ingenuity Pathway Analysis (IPA). In GCs, 296 genes were differentially expressed (P < 0.05); 78% down-regulated in PR–/–. IPA identified genes involved in cancer migration/invasion, chemotaxis, and adhesion; the chemokine receptor Cxcr4, was >3-fold down-regulated in PR–/–. Proteases were also decreased; Adam8 (3.5-fold) and Adamts1 (2.6-fold) in PR–/–. In oviducts, 1003 genes were differentially expressed at P < 0.05 and 266 genes at P < 0.01; 93% were down-regulated in PR–/–. IPA identified genes involved in cell adhesion, movement/migration, invasion and chemotaxis as well as muscle contraction and vasoconstriction. The most highly down-regulated was Itga8 (>9-fold), one of 11 integrins, well known cellular adhesion receptors, differentially expressed. In COCs, 44 genes were differentially expressed (P < 0.05); 52% down-regulated in PR–/–. IPA identified 18 genes (41%) involved in cancer invasion/migration or adhesion. Thus, this study has identified novel gene targets for PGR regulation, which may have essential roles in the molecular control of oocyte release into the oviduct at ovulation.

Assessing the susceptibility of cruciferous Lepidoptera to Cry1Ba2 and Cry1Ca4 for future transgenic cruciferous vegetables

Advances in transgenic plants expressing Bacillus thuringiensis (Bt) insecticidal gene(s) offer a promising alternative to traditional insecticides for control of lepidopteran pests on important cruciferous vegetable crops such as cabbage and cauliflower. A public-private partnership, the Collaboration on Insect Management for Brassicas in Asia and Africa (CIMBAA), was formed in 2005 with the goal of developing dual-gene Bt cauliflower and cabbage, initially for India, to replace the use of broad spectrum, traditional insecticides. As a first step in this effort, the major lepidopteran pests of cruciferous vegetable crops [Plutella xylostella (L.), Pieris rapae (L.), Pieris brassicae (L.), Crocidolomia binotalis (L.), Hellula undalis (F.), Diacrisia obliqua Walker, Spodoptera litura F., and Helicoverpa armigera (Hübner)] were collected over a large geographic area (India, Indonesia, Taiwan, China, Australia, and the United States) and tested against purified Cry1Ba2 and Cry1Ca4 toxins, the toxins proposed to be expressed in the CIMBAA plants. Our results demonstrate that Cry1Ba2 and Cry1Ca4 were effective against the primary target of the CIMBAA plants, P. xylostella, regardless of geographic location, and had LC50 values <1.3 ppm. Furthermore, one or both toxins were effective against the other major pest Lepidoptera, except for S. litura or H. armigera which were less susceptible. No cross-resistance has been found between Cry1Ba2 and Cry1Ca4, suggesting cry1Ba2+cry1Ca4 cauliflower and cabbage could be an effective and sustainable tool to control, P. xylostella, the key lepidopteran pest on cruciferous vegetable crops, as well as most other Lepidoptera. As the CIMBAA plants are being developed, further tests are needed to determine whether they will express these proteins at sufficient levels to control all the Lepidoptera. Sustainable use of the dual-gene plants also is discussed.

Effects of losartan vs candesartan in reducing cardiovascular events in the primary treatment of hypertension

Although angiotensin receptor blockers have different receptor binding properties no comparative studies with cardiovascular disease (CVD) end points have been performed within this class of drugs. The aim of this study was to test the hypothesis that there are blood pressure independent CVD-risk differences between losartan and candesartan treatment in patients with hypertension without known CVD. Seventy-two primary care centres in Sweden were screened for patients who had been prescribed losartan or candesartan between the years 1999 and 2007. Among the 24 943 eligible patients, 14 100 patients were diagnosed with hypertension and prescribed losartan (n=6771) or candesartan (n=7329). Patients were linked to Swedish national hospitalizations and death cause register. There was no difference in blood pressure reduction when comparing the losartan and candesartan groups during follow-up. Compared with the losartan group, the candesartan group had a lower adjusted hazard ratio for total CVD (0.86, 95% confidence interval (CI) 0.77–0.96, P=0.0062), heart failure (0.64, 95% CI 0.50–0.82, P=0.0004), cardiac arrhythmias (0.80, 95% CI 0.65–0.92, P=0.0330), and peripheral artery disease (0.61, 95% CI 0.41–0.91, P=0.0140). No difference in blood pressure reduction was observed suggesting that other mechanisms related to different pharmacological properties of the drugs may explain the divergent clinical outcomes.

Systematic review: the prevalence of idiopathic bile acid malabsorption as diagnosed by SeHCAT scanning in patients with diarrhoea-predominant irritable bowel syndrome

BACKGROUND

Recurrent, watery diarrhoea affects one-third of patients diagnosed with irritable bowel syndrome ('IBS-D'). Idiopathic bile acid malabsorption ('I-BAM') may be the cause.

AIM

To determine the prevalence of I-BAM in patients suffering from IBS-D.

METHODS

A systematic search was performed of publications reporting patients presenting with IBS-D type symptoms, who were subsequently confirmed as having I-BAM by SeHCAT scanning.

RESULTS

Eighteen relevant studies, 15 prospective, comprising 1223 patients were identified. Five studies (429 patients) indicated that 10% (CI: 7-13) patients had severe bile acid malabsorption (SeHCAT 7 day retention <5% of baseline value). 17 studies (1073 patients) indicated that 32% (CI: 29-35) patients had moderate bile acid malabsorption (SeHCAT <10%). 7 studies (618 patients) indicated that 26% (CI: 23-30) patients had mild (SeHCAT <15%) bile acid malabsorption. Pooled data from 15 studies showed a dose-response relationship according to severity of malabsorption to treatment with a bile acid binder: response to colestyramine occurred in 96% of patients with <5% retention, 80% at <10% retention and 70% at <15% retention.

CONCLUSIONS

Idiopathic adult-onset bile acid malabsorption is not rare. International guidelines for the management of irritable bowel syndrome need to be revised so that clinicians become more aware of this possibility.

Systematic review: the prevalence of idiopathic bile acid malabsorption as diagnosed by SeHCAT scanning in patients with diarrhoea-predominant irritable bowel syndrome

BACKGROUND

Recurrent, watery diarrhoea affects one-third of patients diagnosed with irritable bowel syndrome ('IBS-D'). Idiopathic bile acid malabsorption ('I-BAM') may be the cause.

AIM

To determine the prevalence of I-BAM in patients suffering from IBS-D.

METHODS

A systematic search was performed of publications reporting patients presenting with IBS-D type symptoms, who were subsequently confirmed as having I-BAM by SeHCAT scanning.

RESULTS

Eighteen relevant studies, 15 prospective, comprising 1223 patients were identified. Five studies (429 patients) indicated that 10% (CI: 7-13) patients had severe bile acid malabsorption (SeHCAT 7 day retention <5% of baseline value). 17 studies (1073 patients) indicated that 32% (CI: 29-35) patients had moderate bile acid malabsorption (SeHCAT <10%). 7 studies (618 patients) indicated that 26% (CI: 23-30) patients had mild (SeHCAT <15%) bile acid malabsorption. Pooled data from 15 studies showed a dose-response relationship according to severity of malabsorption to treatment with a bile acid binder: response to colestyramine occurred in 96% of patients with <5% retention, 80% at <10% retention and 70% at <15% retention.

CONCLUSIONS

Idiopathic adult-onset bile acid malabsorption is not rare. International guidelines for the management of irritable bowel syndrome need to be revised so that clinicians become more aware of this possibility.

120. OXYGEN REGULATED GENE EXPRESSION IN MOUSE CUMULUS CELLS

Hypoxia inducible factors (HIFs) are heterodimeric transcription factors that mediate the expression of a range of genes in response to low oxygen. Previously we showed that subsequent developmental outcomes were influenced by oxygen levels during in vitro maturation. The aim of the current study was to examine the effects of varying oxygen concentration during in vitro maturation of mouse COCs on expression of HIF target genes in the cumulus cells. I mmature COCs were collected from the ovaries of eCG-stimulated CBAB6F1 females (21 d) and cultured for 17-18 h under 2, 5 or 20% O2. Hyaluronidase-treated and recovered cumulus cells were collected and mRNA extracted for analysis. A microarray approach (Affymetrix 430_2) was used to identify genes in cumulus cells that were differentially expressed under varying oxygen concentrations (2, 5, 10 and 20%). This revealed 218 differentially expressed probes, of which 34 were up-regulated with decreasing oxygen levels. The great majority of these were classified as HIF-regulated genes. Specific analysis from real time RT-PCR of HIF regulated target genes Slc2a1, Ldha, Pgk1, Eno1, Ndrg1, Bnip3 were all significantly up-regulated (by at least 5–fold) when cells were cultured at 2% or 5% oxygen, when compared to 20% oxygen. Hif-1a mRNA decreased when cumulus cells were cultured in 2%, compared to 20% oxygen. This study demonstrates that cumulus cell gene expression is influenced by oxygen concentration, and suggests that these effects are mediated by the HIF transcription factors.

Aspects of intracerebral hematomas--an update

BACKGROUND

In Norway, there are approximately 16000 strokes each year and 15% of these are caused by intracerebral hematomas. Intracerebral hemorrhage (ICH) results from the rupture of blood vessels within the brain parenchyma. ICH occurs as a complication of several diseases, the most prevalent of which is chronic hypertension. When hemorrhage develops in the absence of a pre-existing vascular malformation or brain parenchymal lesion, it is denoted primary ICH. Secondary ICH refers to hemorrhage complicating a pre-existing lesion. Primary ICH is the most common type of hemorrhagic stroke, accounting for approximately 10% of all strokes. Despite aggressive management strategies, the 30-day mortality remains high, at almost 50%, with the majority of deaths occurring within the first 2 days. At 6 months, only 20-30% achieve independent status.

MATERIAL AND METHODS

This article is based on clinical experience, modern therapeutic guidelines for the treatment of intracerebral hematomas and up-to-date medical literature found in Medline. The article discusses the pathophysiology, clinical aspects, treatment, and the prognosis of intracerebral hematomas.

RESULTS AND DISCUSSION

Advances in diagnosis, prognosis, pathophysiology, and treatment over the past few decades have significantly advanced our knowledge of ICH; however, much work still needs to be carried out. Future genetic and epidemiologic studies will help identify at-risk populations and hopefully allow for primary prevention. Randomized controlled studies focusing on novel therapeutics should help to minimize secondary injury and hopefully improve morbidity and mortality.

Needle-stick injuries in primary care in Wales

BACKGROUND

Accidental needle-stick injuries (NSIs) are a hazard for health-care workers and for the general public.

OBJECTIVES

To estimate the presentation rate of NSIs to general medical practices, their relation to practice characteristics, and review practice policies for managing NSIs.

METHOD

Descriptive study using logistic regression analysis.

RESULTS

Annual rates of 2.73 (95% CI 2.08, 3.50) occupational NSIs per 100 clinical practice staff and 2.14 (95% CI 1.39, 3.13) non-occupational NSIs per 100,000 practice population were recorded. Stepwise logistic regressions showed that chance of a practice reporting at least one occupational NSI in previous five years was best predicted by being a single-handed practice (decreased odds). In contrast, the chance of a practice reporting at least one non-occupational NSI was best predicted by being a rural practice (increased odds). About one in five practices possessed no written policy on managing NSIs. Stepwise logistic regressions showed that the chance of a practice owning a NSI policy was best predicted by being located in an LHB area with a coastline (increased odds).

CONCLUSION

NSIs are an important public health issue in Wales. We have tried to address the lack of guidance by developing new guidelines in Wales.

435. Follicle differentiation and luteinisation in the mouse is associated with hypoxia inducible factor activity

Hypoxia inducible factors (HIF) are transcription factors that mediate the response to hypoxic stress. Under hypoxic conditions, HIF is stabilised, translocates to the nucleus, and binds to the Hypoxia Response Elements (HRE) upstream of numerous target genes involved in angiogenesis and glycolysis, including Vegf, Glut-1 and Ldha. Little is known about the role of HIFs in regulating ovarian function. In rat granulosa cells, FSH stimulates HIF 1α via the PI3K/Akt pathway, demonstrating a role for HIFs during follicular development. In contrast, there is limited information regarding the role of HIFs during corpus luteum formation. In this study we investigated whether HIFs play a role in follicle differentiation and luteinisation. Prepubertal C57Bl6 females were stimulated with eCG (5 IU) followed 46 h later by hCG (5 IU). Mice were sacrificed at 0, 4, 8, 12, 16 and 24 h post hCG and granulosa cells were collected for Western analysis of HIF-1a protein. To investigate HIF activation in the ovary, a transgenic reporter mouse line was developed by lenti-viral incorporation of an HRE (4)-SV40-eGFP construct. Ovaries were collected from mice plugged day 1, 4 and 8 for CL analysis in vivo.A time- dependent increase of HIF 1α protein levels in granulosa cells, maximal around time of ovulation, was observed. Ovaries from cycling HRE-eGFP transgenic mice exhibited no eGFP in primordial, primary or preantral follicles. Upon antrum formation, eGFP was evident in occasional sections in antral follicles but HIF signalling was restricted within the theca. In contrast, corpora lutea on pregnancy day 1, 4 and 8 readily expressed eGFP and eGFP expression increases as luteinisation progresses.These results demonstrate that in vivo HIFs may play a role in folliculogenesis, but this is restricted to theca cells of antral follicles before hCG stimulation. Following hCG, maximal HIF activity is associated with the time of ovulation. In addition, HIF activity is maintained during luteinisation.