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Sustainable waste management in the UK: the public health role.

This paper discusses waste management in the UK and its relationship with health. It aims to outline the role of health professionals in the promotion of waste management, and argues for a change in their role in waste management regulation to help make the process more sustainable. The most common definition of sustainable development is that by the Brundtland commission, i.e. "development that meets the needs of the present without compromising the ability of future generations to meet their own needs". Managing waste sites in a manner that minimises toxic impacts on the current and future generations is obviously a crucial part of this. Although the management of waste facilities is extremely complex, the Integrated Pollution Prevention and Control regime, which requires the input of public health professionals on the regulation of such sites, means that all waste management installations should now be operating in a fashion that minimises any toxicological risks to human health. However, the impacts upon climate change, resource use and health inequalities, as well as the effects of waste transportation, are currently not considered to be part of public health professionals' responsibilities when dealing with these sites. There is also no requirement for public health professionals to become involved in waste management planning issues. The fact that public health professionals are not involved in any of these issues makes it unlikely that the potential impacts upon health are being considered fully, and even more unlikely that waste management will become more sustainable. This paper aims to show that by only considering direct toxicological impacts, public health professionals are not fully addressing all the health issues and are not contributing towards sustainability. There is a need for a change in the way that health professionals deal with waste management issues.

Community Health Planning↗

Concepts of marine specimen banking.

For more than a decade environmental specimen banking (ESB) has been an established approach for monitoring and retrospective environmental survey purposes in a number of developed countries. Specimen banking is carried out on regional or national scales for various environmental materials. The ecological or problem-oriented approach, as pursued e.g. in Germany or USA has the advantages of a restricted survey and a clear political mandate. Environmental problems, however, are by no means national or regional issues, since the diversity and dispersion of hazardous substances make environmental monitoring clearly a global affair. The structuring of our environment suggests that banking should not be limited by national boundaries, but rather be based on eco-systematic principles. Such distinct banking efforts should be devoted to the monitoring of physico-chemical aspects of climatic change and air pollution, soil quality, and aquatic monitoring on a world-wide scale. As some experience already exists with specialized banking programs for marine samples, such as the National Marine Mammal Tissue Bank or the Mussel Watch Program in the United States, an international marine specimen bank, based on principles of national ESB's, is advocated to be established in due time. Following the recommendations of the 1992 Rio 'Earth Summit' to pursue sustainable development strategies, such an establishment could strongly facilitate efforts concerning pollution control and mitigation, overexploitation and mining of ocean resources on a regional or global scale.

Animals↗

Environment and health 1, overview and main European issues.

The environment can have an important influence on health. The European Environment Agency (EEA) and the WHO European Centre for Environment and Health (ECEH) developed this publication as a joint effort to draw attention to some environmental issues that have a significant impact on the health of the people of Europe. It represents the logical complement and continuation of their cooperative work. Pooling the immense amounts of data that they have gathered, EEA and ECEH have distilled the resulting knowledge into a brief discussion of the contribution of environmental factors to the main causes of death in Europe, and an examination of three particularly significant issues. These issues meet important criteria. Each is a widespread problem that causes significant damage to the health of many people throughout Europe, and all are amenable to coordinated action that would result in both improved environmental quality and health benefits within a short time. Delaying this action would increase the damage and make these problems harder to solve in the future. This book not only identifies these issues -- air pollution with suspended particles, the microbiological contamination of drinking-water and road traffic accidents -- and sketches the harm that they do, but lists goals and strategies for action now. This book offers useful reading for everyone interested in a healthy environment, health protection and sustainable development. It offers practical suggestions for action to make Europe a safer and healthier place to live, for today's Europeans and tomorrow's.

Accidents, Traffic↗

Characterization and mechanisms of H2O2-induced contractions of pulmonary arteries.

We studied H2O2-induced contractions of isolated rabbit intrapulmonary arteries mounted in standard tissue baths. All vessels were pretreated with a thromboxane A2/prostaglandin H2 receptor antagonist, SQ 29,548, to block immediate transient contractions to H2O2 and to isolate slowly developing sustained contractions. When exposed to H2O2 (0.1, 0.2, 0.3, 0.6, and 1.0 mM) for 30 min, vessels contracted in (0.1, 0.2, 0.3, 0.6, and 1.0 mM) for 30 min, vessels contracted in a concentration-dependent fashion between 0.1 and 0.3 mM H2O2; contractions at 0.6 and 1.0 mM H2O2 were not significantly different from those at 0.3 mM H2O2. During recovery (90 min) from H2O2 exposures, baseline tension was significantly greater, but active tension (10 microM phenylephrine) was significantly less for vessels previously exposed to 0.6 and 1.0 mM H2O2. Contractions to 0.3 mM H2O2 were not blunted by the following interventions: 1) endothelium rubbing, 2) incubation in Ca(2+)-free 100 microM ethylene glycol-bis(beta-aminoethyl ether)-N,N,N',N'-tetraacetic acid (EGTA) Krebs-Ringer solution, 3) incubation in the Ca(2+)-free solution and depletion of ryanodine (20 microM)-sensitive Ca(2+) stores, or 4) pretreatment with the protein kinase C inhibitor 1-(5-isoquinolinylsulfonyl)-3-methyl-piperazine (20 microM). However, contractions were depressed by approximately 50% when vessels were pretreated with the phospholipase C/serine esterase inhibitor 2-nitro-4-carboxy-phenyl-N,N-diphenylcarbamate (50 microM). These results suggest that slow-developing contractions to H2O2 are concentration dependent and may result, in part, from activation of a serine esterase(s) and/or phospholipase C.

Animals↗

Sustaining rural maternity care--don't forget the RNs.

INTRODUCTION: Registered nurses provide intrapartum care to women who choose to have their babies in hospital. Considering the current national shortage of nurses, the ability of registered nurses to continue to care for women, especially in small rural hospitals, is a critical concern. PURPOSES: The purposes of the study were 1) to conduct a systematic review of the maternal-child-nursing literature in rural locations; and 2) to identify one rural Ontario hospital where nurses and physicians deliver care to women with low-risk pregnancies, and then conduct an institutional ethnography to understand the enablers and barriers to low-risk rural maternity care. METHODS: A literature search was conducted to determine the state of rural registered nurses; and a telephone survey of 25 rural Ontario hospitals was undertaken to locate a hospital in which an institutional ethnography study could be conducted. RESULTS: Registered nurses in rural areas are more likely to be multi-specialists than generalists because of the need to adapt to emergencies across the life continuum. To care for pregnant women and their families, registered nurses require many of the same considerations that physicians have outlined: access to continuing education, appropriate call-back schedules, support from other health care professionals and administrators, and a value system that respects their expertise. Results from the ethnography of one Ontario health care institution revealed that when these aforementioned considerations are addressed, registered nurses are able to provide safe, comprehensive low-risk care in a rural maternity programme. CONCLUSIONS: Registered nurses play an important collaborative role in maternity care. We need Canadian data on registered nurses so that we can educate, recruit and retain them to care for women with low-risk pregnancies in rural and remote ares of Canada. Nursing services should be reviewed. Collaborative care models integrating newer professionals such as midwives, as well as understanding the role of doulas, may help in developing sustainable care to rural women.

Anthropology, Cultural↗

Effectiveness of artificial intelligence in nursing simulation education: A systematic review, meta-analysis and bibliometric visualization analysis.

OBJECTIVES: To synthesize the roles and core functions of AI in nursing simulation education for nursing students via systematic review, quantitatively evaluate its effects on students' knowledge and skill outcomes through meta-analysis, and map the research landscape and development trends of this field through bibliometric visualization analysis. DESIGN: Systematic review, meta-analysis and bibliometric visualization analysis. DATA SOURCES: Eight electronic databases: PubMed, Web of Science, MEDLINE, ERIC, Academic Search Complete, China National Knowledge Infrastructure (CNKI), Wanfang Database, VIP Chinese Science and Technology Journal Database (VIP) were employed to search studies from the time of construction to 16 December 2025. REVIEW METHODS: Studies meeting the inclusion criteria were screened. The revised Cochrane Risk of Bias tool (ROB 2) and Joanna Briggs Institute (JBI) critical appraisal checklists were used for quality assessment. Meta-analysis was performed with Review Manager 5.4, and bibliometric visualization analysis was conducted using VOSviewer 1.6.20 and Bibliometrix (based on R4.4.3). RESULTS: A total of 61 studies were included. AI primarily played two roles in nursing simulation education: peer-type new subject (n = 24) and direct mediator (n = 22). Meta-analysis showed that AI interventions significantly improved nursing students' knowledge (SMD = 1.49, 95% CI [0.55,2.43], p = 0.002) and skills (SMD = 0.66, 95% CI [0.02,1.31], p = 0.04). Bibliometric analysis identified that the United States of America and China were the two main contributing countries in this field, and the key motor themes included generative artificial intelligence, virtual patients, and geriatric care. CONCLUSIONS: AI exerts positive effects on nursing students' knowledge acquisition and skill enhancement in simulation education, with peer-type new subject and direct mediator as the dominant roles. Future research should focus on expanding AI applications in multi-specialty simulation scenarios, activating the data-driven value of machine learning, and strengthening international collaboration and standardization construction, so as to promote the sustainable development of AI-integrated nursing simulation education.

Humans↗

Urbanization in sub-saharan Africa and implication for malaria control.

Malaria not only remains a leading cause of morbidity and mortality, but it also impedes socioeconomic development, particularly in sub-Saharan Africa. Rapid and unprecedented urbanization, going hand-in-hand with often declining economies, might have profound implications for the epidemiology and control of malaria, as the relative disease burden increases among urban dwellers. Reviewing the literature and using a modeling approach, we find that entomologic inoculation rates in cities range from 0 to 54 per year, depending on the degree of urbanization, the spatial location within a city, and overall living conditions. Using the latest United Nations figures on urbanization prospects, nighttime light remotely sensed images, and the "Mapping Malaria Risk in Africa" results on climate suitability for stable malaria transmission, we estimate that 200 million people (24.6% of the total African population) currently live in urban settings where they are at risk of contracting the disease. Importantly, the estimated total surface area covered by these urban settings is only approximately 1.1-1.6% of the total African surface. Considering different plausible scenarios, we estimate an annual incidence of 24.8-103.2 million cases of clinical malaria attacks among urban dwellers in Africa. These figures translate to 6-28% of the estimated global annual disease incidence. Against this background, basic health care delivery systems providing early diagnosis and early treatment and preventive actions through mother and child health programs and the promotion of insecticide-treated bed nets for the rapidly growing numbers of the urban poor must be improved alongside well-tailored and integrated malaria control strategies. We propose environmental management and larviciding within well-specified productive sites as a main feature for such an integrated control approach. Mitigation of the current burden of malaria in urban African settings, in turn, is a necessity for stimulating environmentally and socially sustainable development.

Africa South of the Sahara↗

Respiratory and metabolic responses to early postnatal chronic intermittent hypoxia and sustained hypoxia in the developing rat.

Exposure to sustained hypoxia (SH) differentially modifies the hypoxic ventilatory response (HVR) in adults and developing rats. We examined the possibility that postnatal intermittent hypoxia (IH), a more prevalent clinical condition than SH, may lead to significant modifications of ventilatory patterning during development. Sprague-Dawley rat pups were exposed as of the d 1 of life to either SH (10% O2) or IH [alternating room air (RA) and 10% O2 every 90 s] for up to 30 d; controls were exposed to normoxia. HVR (10% O2 for 20 min) was assessed in unrestrained pups at 5, 10, 15, and 30 d of age using whole-body plethysmography. IH pups displayed higher normoxic ventilation (VE) at all ages (p < 0.001 versus control; n = 12 per group), which was not observed in SH animals until 10 d of exposure (p < 0.001 versus control; n = 12 per group). Furthermore, both SH and IH modified properties of peak HVR (pHVR), as well as those of the ensuing hypoxic ventilatory decline (HVD); however, the ventilatory strategies adopted after SH and IH greatly differed. We conclude that both postnatal IH and SH modify normal ventilatory patterning and induce altered HVR, but differ in the ventilatory strategies adopted to mount HVR responses.

Animals↗

Morphological characteristics of layer II projection neurons in the rat medial entorhinal cortex.

The entorhinal cortex receives inputs from a variety of neocortical regions. Neurons in layer II of the entorhinal cortex originate one component of the perforant path which conveys this information to the dentate gyrus and hippocampus. The current study extends our previous work on the electro-responsive properties of layer II neurons of the medial entorhinal cortex in which we distinguished two categories of layer II neurons based on their electrophysiological attributes (Alonso and Klink [1993] J Neurophysiol 70: 128-143). Here we report on the morphological features of layer II projection neurons, as revealed by in vitro intracellular injection of biocytin. We now report that the two electrophysiologically distinct types of neurons correspond to morphologically distinct types of cells. All neurons (65% of the total cells recorded) that developed sustained, subthreshold, sinusoidal membrane potential oscillations were found to have a stellate appearance. Neurons that did not exhibit oscillatory behavior had either a pyramidal-like (32%) or a horizontal cell morphology (3%). Stellate cells had multiple, thick, primary dendrites. Their widely diverging upper dendritic domain expanded mediolaterally over a distance of around 500 microns close to the pial surface. This mediolateral extent was more than double that of the pyramidal-like cells. Dendrites of stellate cells demonstrated long dendritic appendages, and their dendritic spines had a more complex morphology than those of nonstellates. The stellate cell axons emerged from a primary dendrite and were more than double the thickness (approximately 1.4 microns) of the axons of nonstellate cells. Recurrent axonal collaterization appeared more extensive in axons arising from stellate cells than from pyramidal-like cells.

Animals↗

A prospective randomized trial of HLA-matched versus mismatched single-donor platelet transfusions in cancer patients.

The use of histocompatability antigen (HLA)-matched platelets has been advocated for the support of thrombocytopenic cancer patients. We randomized 78 newly diagnosed cancer patients prospectively (before thrombocytopenia) to receive either HLA-matched or mismatched single-donor platelet transfusions. Three hundred forty-one platelet transfusions were given for 80 separate episodes of therapy-induced thrombocytopenia in 33 patients. Forty-five patients receiving intensive chemotherapy did not develop significant (less than 20,000 platelets/mm3) thrombocytopenia and did not receive a platelet transfusion. No marked difference was observed between the matched and mismatched groups in regard to number of total platelet transfusions per patient (median, 3 vs. 5, respectively; P = 0.076), number of platelet transfusions per episode (median, 3.0 vs. 3.5, respectively; P = 0.28), or days between transfusions (median, 2 vs. 2, respectively, P greater than 0.4). Bleeding episodes, although rare, tended to be of increased severity in the mismatched group. Febrile patients receiving mismatched platelets tended to have a lower posttransfusion increment increase than their nonfebrile counterparts (P = 0.068), although a similar trend could not be demonstrated between febrile and nonfebrile patients who received matched platelets (P = 0.22). Patients treated as outpatients had significantly higher posttransfusion increments than when transfused as inpatients when they were given mismatched platelets (P less than 0.0005). Development of antiplatelet antibody did not appear to affect response to platelet transfusions. Only one patient developed sustained high-level antibody titers. In patients where thrombocytopenia was significant, the transfusion of HLA-matched platelets did not appear to offer a significant advantage. However, HLA-matched platelet transfusions tended to be associated with higher posttransfusion increments in febrile patients and a trend toward fewer severe bleeding episodes. A multi-institution trial containing a large number of patients is needed to evaluate trends observed in this study.

Adolescent↗

River Rhine: from sewer to the spring of life.

Water is the key issue in a number of declarations made by several eminent international commissions in recent years. The availability of clean and unpolluted water is crucial to sustainable development. The River Rhine was turned by pollution into the sewer of Western Europe; environmental protection measures, changes in industrial production and consumers' behaviour and remedial measures have drastically improved the quality of Rhine water, which, besides being the main water-way in Europe, also serves as a source of drinking water for a large population and is used for recreational purposes. Small occasional accidents, major spills, very remote accidents, war activities, etc. threaten the full recovery of what is the socially and economically most important watercourse in Europe. The organizational and technological measures taken to protect the Rhine from pollution can serve as an example of how other major freshwater sources could be protected from contamination or how existing pollution could be remedied.

Accidents↗

Multidimensional gas chromatographic determination of paraffins, olefins and aromatics in naphthas.

In order to cope with the increasing demand for gasoline and the need to reduce environmental impact for sustainable development, refineries have installed refining technology by introducing cracking, reforming, isomerization and alkylation. The standard EN 228: 2004 outlines the specification that gasoline, deriving from the blend of several fractions, must have for use in modem piston engines. Naphtha is one of the products from distilling crude oil that can be used as starting material in the reforming process whose derivatives, which are a fraction of gasoline, depend on the composition of the naphtha. Knowledge of the naphtha composition thus enables to provide the final composition of the products of reforming, the efficiency of the plant and also provides information about the crude oil used. In this paper some naphtha samples were analysed by multidimensional gas chromatography. This technique allows in a single analysis a good separation of the hydrocarbon types and within each hydrocarbon type a good carbon number separation.

Alkanes↗

Issues of work intensity, pace, and sustainability in relation to work context and nutritional status.

This article raises issues about work intensity, pace, and sustainability during physical activity, focusing attention on the nature of work in labor-intensive societies, the management of exertion in habitual tasks, and the health and broad socioeconomic correlates of alternative ways to regulate work patterns. At the heart of this review are concerns to document human adaptability (in terms of the physical and behavioral management of heavy work) and to renew debate regarding the conceptualization and measurement of work intensity (variously evaluated in absolute or relative terms, as indexed by oxygen consumption, energy expenditure, percentage maximal work capacity, heart rate elevation, time and motion indicators, or physiological cost). Three questions are examined: Is heavy work primarily a matter of time or energy intensity? How is heavy work habitually sustained? What is the bigger picture relating work performance to work context and to nutritional or health status? It is argued that many arduous activities, such as carrying loads, demand endurance over time rather than intensive effort per unit time, and that work pace management lies in regulating both the rate of work and the time in rest during physical activity. Furthermore, strategies that maximize long-term endurance (adopted by "tortoises") and those that maximize short-term productivity (adopted by "hares") are appropriate to different work contexts (e.g., a subsistence or wage-labor economy) and suit individuals with different health status and ability. Thus, work intensity is an important aspect of the links between physical activity, health, productivity, and society, as noted in literature reviewing objectives for sustainable development and public health messages for disease risk management. These areas of scholarship are underresearched, partly because consensus has been slow in agreeing on which are the best measures of work pace and work intensity for use in field situations, and which are the most meaningful thresholds for evaluating absolute or relative effort across a range of populations.

Agriculture↗

Pulsus alternans induced by inferior vena caval occlusion in man.

To assess the effect of rapid preload reduction on left ventricular performance in nonischemic cardiomyopathy, 11 patients were studied during inferior vena caval (IVC) balloon occlusion. Five developed sustained pulsus alternans. During pulsus alternans, the strong beats demonstrated systolic performance characteristics similar to baseline values, despite a drop in both left ventricular (LV) end-diastolic diameter (66 +/- 13 to 61 +/- 13 mm; p less than 0.05) and LV end-diastolic pressure (21 +/- 8 to 9 +/- 6 mmHg; p less than 0.05). In contrast, the weak beats demonstrated a reduction in peak systolic pressure (130 +/- 36 to 109 +/- 33 mmHg; p less than 0.02), fractional shortening (20% +/- 4% to 17% +/- 9%; p less than 0.05) and peak positive dP/dt (1,006 +/- 224 to 921 +/- 287 mmHg; p less than 0.05). Measures of diastolic performance (peak negative dP/dt, the time constant of LV relaxation, the length of diastasis, and LV end-diastolic stress) were not different between baseline beats and the strong beats; and only LV end-diastolic stress differed when baseline beats were compared to the weak beats. When the strong beats were compared to the weak beats during induced pulsus alternans, significant differences were observed in peak systolic pressure, peak positive dP/dt, and fractional shortening, but no differences in any measured diastolic parameter was observed. A slight difference was noted in the left ventricular end-diastolic diameters, with the weak beat consistently beginning at a slightly smaller diameter (61 +/- 13; mm vs 59 +/- 13; p less than 0.05). In summary, these data are consistent with an augmentation and deletion of intrinsic contractile forces in association with an alternation in preload on a beat-to-beat basis as best describing left ventricular performance during pulsus alternans.

Blood Pressure↗

Left main percutaneous transluminal coronary angioplasty with the autoperfusion catheter in an animal model.

Left main coronary angioplasty is associated with high risk because of interruption of blood flow to much of the left ventricle during balloon inflation. An "autoperfusion" balloon angioplasty catheter that allows blood to flow passively distal to an inflated balloon was tested in dogs and compared with inflations with standard balloon catheters. During 3 min occlusions of the left main coronary artery with the autoperfusion catheter, regional myocardial blood flow was preserved at 0.60 +/- 0.14 ml/min/g, compared with 0.07 +/- 0.03 ml/min/g during inflation with standard balloon catheters (P less than 0.01). Similarly, at the end of 3 min of inflation, left ventricular systolic pressure and dP/dt were maintained with autoperfusion catheter inflation, but they were severely depressed after standard angioplasty balloon inflation. All seven dogs survived autoperfusion balloon inflation, whereas five of seven developed sustained ventricular tachycardia and/or ventricular fibrillation during or after standard balloon inflation. Thus, distal blood flow, hemodynamics, and survival were preserved during autoperfusion balloon inflation in the left main coronary artery.

Angioplasty, Balloon, Coronary↗

Laser catheter ablation of simulated ventricular tachycardia.

Catheter-directed laser injury of the left ventricular endocardium for ablation of ventricular tachycardia was studied in a canine model of simulated ventricular tachycardia. Bipolar plunge electrodes were placed at thoracotomy into the left ventricular endocardium in nine anesthetized dogs. Ventricular tachycardia was simulated by pacing at 200 beats per minute. After four days of recovery, catheter-directed neodymium:yttrium-aluminum-garnet laser injury was produced at the site of earliest recorded electrical activation during pacing tachycardia as detected by endocardial catheter mapping. Immediately after laser injury and again five days after injury, pacing tachycardia was attempted. Failure to pace after laser injury was defined as successful arrhythmia ablation. In 3/9 (33%) experiments, the laser-injured tissue surrounded the tachycardia source (pacing wires), and pacing-simulated ventricular tachycardia was prevented. When the laser injury did not involve the tachycardia source, 6/9 animals, due to limitations of the mapping system, pacing was not prevented. One animal developed sustained ventricular tachycardia during laser injury, with conversion to sinus rhythm by lidocaine. One animal, without recognized ventricular arrhythmia, died five days after laser injury. No unusual findings were noted at autopsy. These preliminary data suggest that catheter-directed laser-induced injury can ablate arrhythmia sources. Further studies are indicated in a more physiologic model, and the safety and risks of the procedure need further evaluation.

Animals↗

Degradation of maternal mRNA in mouse embryos: selective degradation of specific mRNAs after fertilization.

During oogenesis, mRNA is actively transcribed and accumulated in growing oocytes, but this transcription stops before the oocytes grow to their full size. The accumulated maternal mRNA is used for protein synthesis in the oocytes during meiotic maturation and even in the embryos to sustain development after fertilization. Therefore, the degradation of accumulated maternal mRNA starts during meiotic maturation, but its rate is slow. Nevertheless, some mRNA species should rapidly degrade after fertilization if they encode proteins that play a role in specific events during meiosis and are detrimental for development after fertilization. In this study, to identify the selective degradation of maternal transcripts after fertilization, we sought mRNAs that are degraded in the early hours after fertilization by constructing an oocyte cDNA library after subtracting the cDNA of embryos at the mid one-cell stage. H1oo, c-mos, tPA (tissue type plasminogen activator gene), and Gdf9 were identified as genes whose transcripts undergo rapid degradation after fertilization. RT-PCR analysis showed that none of these transcripts was expressed during pre-implantation development once they were eliminated, suggesting that the mRNA species that are required for oogenesis, but not for early pre-implantation development, are degraded rapidly after fertilization. Microinjection of chimeric mRNAs in which the coding and 3'-untranslated regions (3'UTR) were exchanged between c-mos and hypoxanthine phosphoribosyltransferase mRNAs revealed that the 3'UTR plays a role in the rapid degradation that occurs after fertilization. Cytoplasmic polyadenylation elements (CPEs) was found near a poly(A) signal in the 3'UTR of all the mRNA species identified as rapidly degrading mRNA. The mechanism for the selective degradation is discussed, in relation to its biological significance.

3' Untranslated Regions↗

The influence of follicle size, FSH-enriched maturation medium, and early cleavage on bovine oocyte maternal mRNA levels.

Transcription is arrested in the bovine oocyte within the first few hours of in vitro maturation, thus the stored maternal mRNAs accumulated in the oocyte are essential to sustain development until the Maternal-Zygotic Transition. In vivo matured oocytes have superior blastocyst formation rates than in vitro matured oocytes, suggesting that the mRNA content of these oocytes is of higher quality. To determine which transcripts may be associated with developmental competence, a Suppressive Subtractive Hybridization was performed between oocytes collected by ovariectomy at 6 hr post-LH surge and oocytes from slaughterhouse collected after 6 hr of maturation, resulting in a library enriched in these functionally important mRNAs. The clones were spotted onto a cDNA microarray and transcripts potentially associated with developmental competence were hybridized onto these slides. Hybridizations were performed with transcripts up-regulated in oocytes cultured for 6 hr in the presence or absence of rFSH in vitro, and secondly with transcripts up regulated in early-cleaving embryos versus those at the one-cell stage at 36 hr postfertilization. From these hybridizations, 13 candidates were selected. Their functional association with embryonic competence was validated by measuring their relative transcript levels by quantitative real-time PCR in eight different conditions: oocytes cultured with or without rFSH, early--versus late-cleaving embryos, and oocytes from different follicle sizes (1-3, 3-5, 5-8, and >8 mm of diameter). The gene candidates CCNB2, PTTG1, H2A, CKS1, PSMB2, SKIIP, CDC5L, RGS16, and PRDX1 showed a significant quantitative association with competence compared to BMP15, GDF9, CCNB1, and STK6.

Animals↗