448 research outputs found

    IVF/ICSI outcomes after culture of human embryos at low oxygen tension: a meta-analysis

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    <p>Abstract</p> <p>Background</p> <p>Improved pregnancy, implantation, and birth rates have been reported after the use of reduced O2 concentration during embryo culture, mainly due to a reduction of the cumulative detrimental effects of reactive oxygen species. However, some studies have failed to report any positive effects. The objective of this meta-analysis was to evaluate the effect of a low-O2 environment on IVF/intracytoplasmic sperm injection (ICSI) outcomes.</p> <p>Methods</p> <p>All available published and ongoing randomised trials that compared the effects of low (~5%; OC~5) and atmospheric (~20%; OC~20) oxygen concentrations on IVF/ICSI outcomes were included. Search strategies included online surveys of databases from 1980 to 2011. The outcomes measured were fertilisation rate, implantation rate and ongoing pregnancy rates. The fixed effects model was used to calculate the odds ratio.</p> <p>Results</p> <p>Seven studies were included in this analysis. The pooled fertilisation rate did not differ significantly (<it>P </it>= 0.54) between the group of oocytes cultured at low O2 tension and the group at atmospheric O2 tension. Concerning all cycles, the implantation (<it>P </it>= 0.06) and ongoing pregnancy (<it>P </it>= 0.051) rates were not significantly different between the group receiving transferred sets containing only OC~5 embryos and the group receiving transferred sets with only OC~20 embryos. In a meta-analysis performed for only those trials in which embryos were transferred on day 2/3, implantation (<it>P </it>= 0.63) and ongoing pregnancy (<it>P </it>= 0.19) rates were not significantly different between the groups. In contrast, when a meta-analysis was performed using only trials in which embryos were transferred on days 5 and 6 (at the blastocyst stage), the group with transferred sets of only OC~5 embryos showed a statistically significantly higher implantation rate (<it>P </it>= 0.006) than the group receiving transferred sets with only OC~20 embryos, although the ongoing pregnancy (<it>P </it>= 0.19) rates were not significantly different between the groups.</p> <p>Conclusions</p> <p>Despite some promising results, it seems too early to conclude that low O2 culture has an effect on IVF outcome. Additional randomised controlled trials are necessary before evidence-based recommendations can be provided. It should be emphasised that the present meta-analysis does not provide any evidence that low oxygen concentration is unnecessary.</p

    Mesenchymal stem cells secretome-induced axonal outgrowth is mediated by BDNF

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    Mesenchymal stem cells (MSCs) have been used for cell-based therapies in regenerative medicine, with increasing importance in central and peripheral nervous system repair. However, MSCs grafting present disadvantages, such as, a high number of cells required for transplantation and low survival rate when transplanted into the central nervous system (CNS). In line with this, MSCs secretome which present on its composition a wide range of molecules (neurotrophins, cytokines) and microvesicles, can be a solution to surpass these problems. However, the effect of MSCs secretome in axonal elongation is poorly understood. In this study, we demonstrate that application of MSCs secretome to both rat cortical and hippocampal neurons induces an increase in axonal length. In addition, we show that this growth effect is axonal intrinsic with no contribution from the cell body. To further understand which are the molecules required for secretome-induced axonal outgrowth effect, we depleted brain-derived neurotrophic factor (BDNF) from the secretome. Our results show that in the absence of BDNF, secretome-induced axonal elongation effect is lost and that axons present a reduced axonal growth rate. Altogether, our results demonstrate that MSCs secretome is able to promote axonal outgrowth in CNS neurons and this effect is mediated by BDNF.European Regional Development Fund (ERDF), through the Centro 2020 Regional Operational Programme under project CENTRO-01–0145-FEDER-000008:BrainHealth 2020, and through the COMPETE 2020 - Operational Programme for Competitiveness and Internationalisation and Portuguese national funds via FCT – Fundação para a Ciência e a Tecnologia, I.P., under projects PTDC/SAU-NEU/104100/2008, EXPL/NEU-NMC/0541/2012 and UID/NEU/04539/2013. This work was also funded by Marie Curie Actions - International reintegration grant #249288, 7th Framework programme, EU. Partially funded by Prémios Santa Casa Neurociências - Prize Melo e Castro for Spinal Cord Injury Research; Portuguese Foundation for Science and Technology (IF Development Grant to A.J.S.); NORTE-01-0145-FEDER-000013, supported by the Northern Portugal Regional Operational Programme; by FEDER funds, through the Competitiveness Factors Operational Programme (COMPETE), and by national funds, through the Foundation for Science and Technology (FCT), under the scope of the project POCI-01-0145-FEDER-007038. The authors would also like to acknowledge Prof. J.E. Davies from the Institute of Biomaterials and Biomedical Engineering at the University of Toronto, Canada, for kindly providing some of the HUCPVCs lots used in the present workinfo:eu-repo/semantics/publishedVersio

    A retrospective population based cohort study of access to specialist palliative care in the last year of life: who is still missing out a decade on?

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    Background: Historically, specialist palliative care has been accessed by a greater proportion of people dying with cancer compared to people with other life-limiting conditions. More recently, a variety of measures to improve access to palliative care for people dying from non-cancer conditions have been implemented. There are few rigorous population-based studies that document changes in palliative care service delivery relative to the number of patients who could benefit from such services. Method: A retrospective cohort study of the last year of life of persons with an underlying cause of death in 2009-10 from cancer, heart failure, renal failure, liver failure, chronic obstructive pulmonary disease, Alzheimer's disease, motor neurone disease, Parkinson's disease, Huntington's disease and/or HIV/AIDS. The proportion of decedents receiving specialist palliative care was compared to a 2000-02 cohort. Logistic regression models were used identify social and demographic factors associated with accessing specialist palliative care. Results: There were 12,817 deaths included into the cohort; 7166 (56 %) from cancer, 527 (4 %) from both cancer and non-cancer conditions and 5124 (40 %) from non-cancer conditions. Overall, 46.3 % of decedents received community and/or hospital based specialist palliative care; a 3.5 % (95 % CI 2.3-4.7) increase on specialist palliative care access reported ten years earlier. The majority (69 %; n?=?4928) of decedents with cancer accessed palliative care during the last year of life. Only 14 % (n?=?729) of decedents with non-cancer conditions accessed specialist palliative care, however, this represented a 6.1 % (95 % CI 4.9-7.3) increase on the specialist palliative care access reported for the same decedent group ten years earlier. Compared to decedents with heart failure, increased odds of palliative care access was observed for decedents with cancer (OR 10.5; 95 % CI 9.1-12.2), renal failure (OR 1.5; 95 % CI 1.3-1.9), liver failure (OR 2.3; 95 % CI 1.7-3.3) or motor neurone disease (OR 4.5; 95 % CI 3.1-6.6). Living in major cities, being female, having a partner and living in a private residence was associated with increased odds of access to specialist palliative care. CONCLUSION: There is small but significant increase in access to specialist palliative care services in Western Australia, specifically in patients dying with non-cancer conditions

    Hyperparasitaemia and low dosing are an important source of anti-malarial drug resistance

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    BACKGROUND: Preventing the emergence of anti-malarial drug resistance is critical for the success of current malaria elimination efforts. Prevention strategies have focused predominantly on qualitative factors, such as choice of drugs, use of combinations and deployment of multiple first-line treatments. The importance of anti-malarial treatment dosing has been underappreciated. Treatment recommendations are often for the lowest doses that produce "satisfactory" results. METHODS: The probability of de-novo resistant malaria parasites surviving and transmitting depends on the relationship between their degree of resistance and the blood concentration profiles of the anti-malarial drug to which they are exposed. The conditions required for the in-vivo selection of de-novo emergent resistant malaria parasites were examined and relative probabilities assessed. RESULTS: Recrudescence is essential for the transmission of de-novo resistance. For rapidly eliminated anti-malarials high-grade resistance can arise from a single drug exposure, but low-grade resistance can arise only from repeated inadequate treatments. Resistance to artemisinins is, therefore, unlikely to emerge with single drug exposures. Hyperparasitaemic patients are an important source of de-novo anti-malarial drug resistance. Their parasite populations are larger, their control of the infection insufficient, and their rates of recrudescence following anti-malarial treatment are high. As use of substandard drugs, poor adherence, unusual pharmacokinetics, and inadequate immune responses are host characteristics, likely to pertain to each recurrence of infection, a small subgroup of patients provides the particular circumstances conducive to de-novo resistance selection and transmission. CONCLUSION: Current dosing recommendations provide a resistance selection opportunity in those patients with low drug levels and high parasite burdens (often children or pregnant women). Patients with hyperparasitaemia who receive outpatient treatments provide the greatest risk of selecting de-novo resistant parasites. This emphasizes the importance of ensuring that only quality-assured anti-malarial combinations are used, that treatment doses are optimized on the basis of pharmacodynamic and pharmacokinetic assessments in the target populations, and that patients with heavy parasite burdens are identified and receive sufficient treatment to prevent recrudescence

    Prevalence and risk factors for Hepatitis C and HIV-1 infections among pregnant women in Central Brazil

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    <p>Abstract</p> <p>Background</p> <p>Hepatitis C (HCV) and human immunodeficiency virus (HIV) infections are a major burden to public health worldwide. Routine antenatal HIV-1 screening to prevent maternal-infant transmission is universally recommended. Our objectives were to evaluate the prevalence of and potential risk factors for HCV and HIV infection among pregnant women who attended prenatal care under the coverage of public health in Central Brazil.</p> <p>Methods</p> <p>Screening and counselling for HIV and HCV infections was offered free of charge to all pregnant women attending antenatal clinic (ANC) in the public health system, in Goiania city (~1.1 million inhabitants) during 2004–2005. Initial screening was performed on a dried blood spot collected onto standard filter paper; positive or indeterminate results were confirmed by a second blood sample. HCV infection was defined as a positive or indeterminate sample (EIA test) and confirmed HCV-RNA technique. HIV infection was defined according to standard criteria. Factors associated with HIV and HCV infections were identified with logistic regression. The number needed to screen (NNS) to prevent one case of infant HIV infection was calculated using the Monte Carlo simulation method.</p> <p>Results</p> <p>A total of 28,561 pregnant women were screened for HCV and HIV-1 in ANC. Mean maternal age was 23.9 years (SD = 5.6), with 45% of the women experiencing their first pregnancy. Prevalence of HCV infection was 0.15% (95% CI 0.11%–0.20%), and the risk increased with age (p < 0.01). The prevalence of anti-HIV infection was 0.09% (95% CI 0.06%–0.14%). Black women had a 4.9-fold (95% CI 1.42–16.95) greater risk of HIV-1 infection compared to non-black women. NNS to prevent one case of infant HIV infection ranged from 4,141 to 13,928.</p> <p>Conclusion</p> <p>The prevalence of HIV and HCV infections were low among pregnant women, with high acceptability rates in the opt-in strategy in primary care. Older maternal age was a risk factor for HCV and antenatal HCV testing does not fulfill the requirements for screening recommendation. The finding of higher risk of HIV-1 infection among black women despite being in consonance with the HIV-1 ethnic pattern in some American regions cannot be ruled out to be a surrogate marker of socio-economic condition.</p

    A922 Sequential measurement of 1 hour creatinine clearance (1-CRCL) in critically ill patients at risk of acute kidney injury (AKI)

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