1,128 research outputs found
Necrotrophic growth of legionella pneumophila
This study examined whether Legionella pneumophila is able to thrive on heat-killed microbial cells (necrotrophy) present in biofilms or heat-treated water systems. Quantification by means of plate counting, real-time PCR, and flow cytometry demonstrated necrotrophic growth of L. pneumophila in water after 96 h, when at least 100 dead cells are available to one L. pneumophila cell. Compared to the starting concentration of L. pneumophila, the maximum observed necrotrophic growth was 1.89 log units for real-time PCR and 1.49 log units for plate counting. The average growth was 1.57 ± 0.32 log units (n = 5) for real-time PCR and 1.14 ± 0.35 log units (n = 5) for plate counting. Viability staining and flow cytometry showed that the fraction of living cells in the L. pneumophila population rose from the initial 54% to 82% after 96 h. Growth was measured on heat-killed Pseudomonas putida, Escherichia coli, Acanthamoeba castellanii, Saccharomyces boulardii, and a biofilm sample. Gram-positive organisms did not result in significant growth of L. pneumophila, probably due to their robust cell wall structure. Although necrotrophy showed lower growth yields compared to replication within protozoan hosts, these findings indicate that it may be of major importance in the environmental persistence of L. pneumophila. Techniques aimed at the elimination of protozoa or biofilm from water systems will not necessarily result in a subsequent removal of L. pneumophila unless the formation of dead microbial cells is minimized
Pregnancy outcomes in Benghazi, Libya, before and during the armed conflict in 2011
Stressful life events experienced by pregnant women may lead to adverse obstetric outcomes. This study in Benghazi compared the rates of preterm, low-birth-weight and caesarean-section births at Al-Jamhouria hospital in the months before and during the armed conflict in Libya in 2011. Data were collected on all women admitted to the delivery ward during February to May 2011 (the months of the most active fighting in the city) (n = 7096), and October to December 2010 (the months immediately before the war) (n = 5935). Compared with the preceding months there was a significant rise during the conflict in the rate of deliveries involving preterm (3.6% versus 2.5%) and low-birth-weight (10.1% versus 8.5%) infants and caesarean sections (26.9% versus 25.3%). Psychosocial stress may have been a factor (among others) in an increase in negative pregnancy outcomes, and obstetric hospitals should be aware of these issues in times of war
The environment effect on operation of in-vessel mirrors for plasma diagnostics in fusion devices
First mirrors will be the plasma facing components of optical diagnostic
systems in ITER. Mirror surfaces will undergo modification caused by erosion
and re-deposition processes [1,2]. As a consequence, the mirror performance may
be changed and may deteriorate [3,4]. In the divertor region it may also be
obscured by deposition [5-7]. The limited access to in-vessel components of
ITER calls for testing the mirror materials in present day devices in order to
gather information on the material damage and degradation of the mirror
performance, i.e. reflectivity. A dedicated experimental programme, First
Mirror Test (FMT), has been initiated at the JET tokamak within the framework
Tritium Retention Studies (TRS).Comment: 12th International Congress on Plasma Physics, 25-29 October 2004,
Nice (France).Submitted by B. Schunke on behalf of V. Voytseny
Pregnancy and childbirth outcomes among adolescent mothers: a World Health Organization multicountry study
Objective: To investigate the risk of adverse pregnancy outcomes among adolescents in 29 countries. Design: Secondary analysis using facility-based cross-sectional data of the World Health Organization Multicountry Survey on Maternal and Newborn Health.
Setting: Twenty-nine countries in Africa, Latin America, Asia and the Middle East.
Population: Women admitted for delivery in 359 health facilities during 2–4 months between 2010 and 2011.
Methods: Multilevel logistic regression models were used to estimate the association between young maternal age and adverse pregnancy outcomes.
Main outcome measures: Risk of adverse pregnancy outcomes among adolescent mothers.
Results: A total of 124 446 mothers aged ≤24 years and their infants were analysed. Compared with mothers aged 20–24 years, adolescent mothers aged 10–19 years had higher risks of eclampsia, puerperal endometritis, systemic infections, low birthweight, preterm delivery and severe neonatal conditions. The increased risk of intra-hospital early neonatal death among infants born to adolescent mothers was reduced and statistically insignificant after adjustment for gestational age and birthweight, in addition to maternal characteristics, mode of delivery and congenital malformation. The coverage of prophylactic uterotonics, prophylactic antibiotics for caesarean section and antenatal corticosteroids for preterm delivery at 26–34 weeks was significantly lower among adolescent mothers.
Conclusions: Adolescent pregnancy was associated with higher risks of adverse pregnancy outcomes. Pregnancy prevention strategies and the improvement of healthcare interventions are crucial to reduce adverse pregnancy outcomes among adolescent women in low- and middle-income countries
Characterisation of the vaginal microflora of human immunodeficiency virus (HIV) positive and negative women in a sub-urban population of Kenya
Lactobacilli predominate normal vaginal microflora and are important in maintenance of vaginal health. The current study set out to identify and compare culture isolates of vaginal microflora of human immunodeficiency virus (HIV) positive (HIV+ ) and HIV negative (HIV- ) women at different phases during menstrual cycle from a sub-urban population of Kenya. Seventy four (74) women, 41 HIV+ and 33 HIV- , followed up two consecutive menstrual cycles, had high vaginal swabs taken to prepare Gram stains for six visits and anaerobic cultures for four. All 751 isolates identified by t-DNA polymerase chain reaction (PCR) belong to 51 species. Species cultured more frequently in HIV+ participants were: Lactobacillus jensenii (p=0.01), Lactobacillus iners (p=0.02), Gardnerella vaginalis (p=0.01) and Peptoniphilus lacrimalis (p=0.01). Species cultured more frequently in HIV- women were Dialister micraerophilus (p=0.02) and Streptococcus agalactiae (p=0.04). Lactobacillus predominating both groups were Lactobacilli crispatus, L. jensenii, L. iners and Lactobacilli vaginalis. Bacterial vaginosis (BV) was equally high in HIV+ and HIV- women. Lactobacillus and BV-associated species were cultured more frequently in HIV+ women. Minor species differences were found. Predominant Lactobacillus in culture were L. crispatus, L. iners, L. jensenii and L. vaginalis. These women had lower concentrations of lactobacilli in vaginal microflora than observed in previous studies of Caucasian women
Study of the volume and spin collapse in orthoferrite LuFeO_3 using LDA+U
Rare earth (R) orthoferrites RFeO_3 exhibit large volume transitions
associated with a spin collapse. We present here ab initio calculations on
LuFeO_3. We show that taking into account the strong correlation among the
Fe-3d electrons is necessary. Indeed, with the LDA+U method in the Projector
Augmented Wave (PAW), we are able to describe the isostructural phase
transition at 50 GPa, as well as a volume discontinuity of 6.0% at the
transition and the considerable reduction of the magnetic moment on the Fe
ions. We further investigate the effect of the variation of U and J and find a
linear dependence of the transition pressure on these parameters. We give an
interpretation for the non-intuitive effect of J. This emphasizes the need for
a correct determination of these parameters especially when the LDA+U is
applied to systems (e.g in geophysical investigations) where the transition
pressure is a priori unknown
Global burden of maternal and congenital syphilis in 2008 and 2012: a health systems modelling study
Background: In 2007, WHO launched a global initiative for the elimination of mother-to-child transmission of syphilis (congenital syphilis). An important aspect of the initiative is strengthening surveillance to monitor progress towards elimination. In 2008, using a health systems model with country data inputs, WHO estimated that 1·4 million maternal syphilis infections caused 520 000 adverse pregnancy outcomes. To assess progress, we updated the 2008 estimates and estimated the 2012 global prevalence and cases of maternal and congenital syphilis.
Methods: We used a health systems model approved by the Child Health Epidemiology Reference Group. WHO and UN databases provided inputs on livebirths, antenatal care coverage, and syphilis testing, seropositivity, and treatment in antenatal care. For 2012 estimates, we used data collected between 2009 and 2012. We updated the 2008 estimates using data collected between 2000 and 2008, compared these with 2012 estimates using data collected between 2009 and 2012, and performed subanalyses to validate results.
Findings: In 2012, an estimated 930 000 maternal syphilis infections caused 350 000 adverse pregnancy outcomes including 143 000 early fetal deaths and stillbirths, 62 000 neonatal deaths, 44 000 preterm or low weight births, and 102 000 infected infants worldwide. Nearly 80% of adverse outcomes (274 000) occurred in women who received antenatal care at least once. Comparing the updated 2008 estimates with the 2012 estimates, maternal syphilis decreased by 38% (from 1 488 394 cases in 2008 to 927 936 cases in 2012) and congenital syphilis decreased by 39% (from 576 784 to 350 915). India represented 65% of the decrease. Analysis excluding India still showed an 18% decrease in maternal and congenital cases of syphilis worldwide.
Interpretation: Maternal and congenital syphilis decreased worldwide from 2008 to 2012, which suggests progress towards the elimination of mother-to-child transmission of syphilis. Nonetheless, maternal syphilis caused substantial adverse pregnancy outcomes, even in women receiving antenatal care. Improved access to quality antenatal care, including syphilis testing and treatment, and robust data are all important for achieving the elimination of mother-to child transmission of syphilis.
Funding: The UNDP-UNFPA-UNICEF-WHO-World Bank Special Programme of Research, Development and Research Training in Human Reproduction in WHO, and the US Centers for Disease Control and Prevention
The gender-based violence and recovery centre at Coast Provincial General Hospital, Mombasa, Kenya: An integrated care model for survivors of sexual violence
Sexual violence (SV) is highly prevalent and a major public health problem globally. In Kenya, an estimated 32% of females and 18% of males were reported to have experienced SV before the age of 18 years. This paper presents a data set collected between 2007 and 2018 and describes the gender-based violence and recovery centre (GBVRC) model under which survivors of SV were cared for at a 24-hour public hospital in Mombasa, Kenya—including its development, implementation, achievements, and challenges. The GBVRC model is a partnership that provides (in addition to emergency healthcare) mental health support, paralegal services, and integrated cooperation with police, judiciary, local leaders, and the wider community. The Mombasa GBVRC has provided post-SV care to 6,575 people reporting SV, of whom 88% were female and over 50% were younger than 16 years. Over 90% of the perpetrators were family, neighbours, community members, or in some other way known to the survivors. The low rate (19%) of attendance by survivors for the second counselling visit suggests a more robust strategy is needed for follow-up—for example, by referring people back to smaller, closer health facilities. A second limitation was a lack of trained staff, although this is an expected issue in sub-Saharan Africa. There was also a low rate of legal resolution to the cases. This may be due to the need for education about the standard of evidence required by courts. The experiences of successful and sustainable implementation of the GBVRC model should strengthen arguments for service delivery for people experiencing SV in this and similar settings
- …