292 research outputs found
Uricult trio as a screening test for bacteriurla in pregnancy
Objective. To establish the effectiveness in an indigent urban population of Uricult Trio as a screening test for asymptomatic bacteriuria in pregnancy and in diagnosing urinary tract infections (UTI) in symptomatic pregnant women. likelihood ratios were established for positive and negative Uricult Trio test results.Subjects. Two populations of patients from the Pretoria region were involved: (J) asymptomatic pregnant women attending the antenatal clinic for the first time or presenting in labour; and (iI) pregnant women with symptoms suggestive of UTI.Method. A midstream urine specimen was collected from the two populations of patients, plated onto the Uricult Trio and sent to the laboratory for culture.Results. The prevalence of asymptomatic bacteriuria in this population was 23%, and for women with symptoms suggestive of UTI, 29%. The likelihood ratios for a positive test were 1.8 and 1.5 for asymptomatic and symptomatic patients respectively. The likelihood ratios for a negative test were 0.35 and 0.44 for asymptomatic and symptomatic patients respectively. Escherichia coli was the causative agent . in 36% of cases.Conclusion. Uricult Trio is not effective as a screening test for asymptomatic bacteriuria in pregnancy or for diagnosing UTIs in women with symptoms suggestive of infection
Stillbirth risk across pregnancy by size for gestational age in Western Cape Province, South Africa: Application of the fetuses-at-risk approach using perinatal audit data
Background. There is little published work on the risk of stillbirth across pregnancy for small-for-gestational-age (SGA) and large-for-gestational (LGA) pregnancies in low-resource settings.Objectives. To compare stillbirth risk across pregnancy between SGA and appropriate-for-gestational-age (AGA) pregnancies in Western Cape Province, South Africa (SA).Methods. A retrospective audit of perinatal mortality data using data from the SA Perinatal Problem Identification Program was conducted. All audited stillbirths with information on size for gestational age (N=677) in the Western Cape between October 2013 and August 2015 were included in the study. The Western Cape has antenatal care (ANC) appointments at booking and at 20, 26, 32, 34, 36, 38 and 41 (if required) weeksâ gestation. A fetuses-at-risk approach was adopted to examine stillbirth risk (28 - 42 weeksâ gestation, â„1Â 000 g) across gestation by size for gestational age (SGA <10th centile Theron growth curves, LGA >90th centile). Stillbirth risk was compared between SGA/LGA and AGA pregnancies.Results. SGA pregnancies were at an increased risk of stillbirth compared with AGA pregnancies between 30 and 40 weeksâ gestation, with the relative risk (RR) ranging from 3.5 (95% confidence interval (CI) 1.6 - 7.6) at 30 weeksâ gestation to 15.3 (95% CI 8.8 - 26.4) at 33 weeksâ gestation (p<0.001). The risk for LGA babies increased by at least 3.5-fold in the later stages of pregnancy (from 37 weeks) (p<0.001). At 38 Â weeks, the greatest increased risk was seen for LGA pregnancies (RR 6.6, 95% CI 3.1 - 14.2; p<0.001).Conclusions. There is an increased risk of stillbirth for SGA pregnancies, specifically between 33 and 40 weeksâ gestation, despite fortnightly ANC visits during this time. LGA pregnancies are at an increased risk of stillbirth after 37 weeksâ gestation. This high-risk period highlights potential issues with the detection of fetuses at risk of stillbirth even when ANC is frequent.
High-speed roll-to-roll manufacturing of graphene using a concentric tube CVD reactor
We present the design of a concentric tube (CT) reactor for roll-to-roll chemical vapor deposition (CVD) on flexible substrates, and its application to continuous production of graphene on copper foil. In the CTCVD reactor, the thin foil substrate is helically wrapped around the inner tube, and translates through the gap between the concentric tubes. We use a bench-scale prototype machine to synthesize graphene on copper substrates at translation speeds varying from 25âmm/min to 500âmm/min, and investigate the influence of process parameters on the uniformity and coverage of graphene on a continuously moving foil. At lower speeds, high-quality monolayer graphene is formed; at higher speeds, rapid nucleation of small graphene domains is observed, yet coalescence is prevented by the limited residence time in the CTCVD system. We show that a smooth isothermal transition between the reducing and carbon-containing atmospheres, enabled by injection of the carbon feedstock via radial holes in the inner tube, is essential to high-quality roll-to-roll graphene CVD. We discuss how the foil quality and microstructure limit the uniformity of graphene over macroscopic dimensions. We conclude by discussing means of scaling and reconfiguring the CTCVD design based on general requirements for 2-D materials manufacturing.National Science Foundation (U.S.). Science, Engineering, and Education for Sustainability (Postdoctoral Fellowship Award 1415129
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Data collection on trafficking in human beings in the EU: Final report
Trafficking in human beings is the buying and selling of women, girls, men, and boys. It has hugely deleterious consequences for individuals, society, and the economy. This is the fourth report published by the European Commission that presents a compilation of statistics at the EU Member State level on trafficking in human beings. This data collection exercise approached all 28-Member States and covers the years 2015 and 2016and updates the 2014 data collection as relevant
Complications in 8,509 laparoscopic Falope ring sterilizations performed under local anaesthesia
The original publication is available at http://www.samj.org.zaCITATION: Pattinson, R. C. et al. 1983. Complications in 8,509 laparoscopic Falope ring sterilizations performed under local anaesthesia. South African Medical Journal, 64:975 - 976.During the 3-year period 1 January 1980 - 31 December 1982, 8,509 laparoscopic Falope ring sterilizations were performed under local anaesthesia in rural areas of the Cape Province by the Sterilization Service of Tygerberg Hospital. Despite the fact that 476 of the patients had undergone previous lower abdominnal surgery, major complications (anaphylactic shock after injections of lignocaine and inadvertent perforation of the bladder by the trocar) occurred in only 2 cases. It was not possible to complete the sterilization under local anaesthesia in 98 cases, resulting in a technical failure rate of 1.15%. A prospective study of the minor complications encountered among the 193 patients sterilized during November 1982 showed that torn tubes occrred in 3.1% and uterine perforation in 2.1%. This can be partially explained by the fact that evidence of previous pelvic infection was seen during laparoscopy in 9.3% of cases. The pregnancy rates after sterilization was 0.28% for the group as a whole.Publisherâs versio
Applying the international classification of diseases to perinatal mortality data, South Africa
OBJECTIVE : To examine the feasibility of applying the International Classification of Diseases-perinatal mortality (ICD-PM) coding to an
existing data set in the classification of perinatal deaths.
METHODS : One author, a researcher with a non-clinical public health background, applied the ICD-PM coding system to South Africaâs national
perinatal mortality audit system, the Perinatal Problem Identification Program. The database for this study included all perinatal deaths
(n = 26 810), defined as either stillbirths (of birth weight > 1000 g and after 28 weeks of gestation) or early neonatal deaths (age 0â7 days),
that occurred between 1 October 2013 and 31 December 2016. A clinical obstetrician verified the coding.
FINDINGS : The South African classification system does not include the timing of death; however, under the ICD-PM system, deaths could
be classified as antepartum (n = 15 619; 58.2%), intrapartum (n = 3725; 14.0%) or neonatal (n = 7466; 27.8%). Further, the South African
classification system linked a maternal condition to only 40.3% (10 802/26 810) of all perinatal deaths; this proportion increased to 68.9%
(18 467/26 810) under the ICD-PM system.
CONCLUSION : The main benefit of using the clinically relevant and user-friendly ICD-PM system was an enhanced understanding of the data,
in terms of both timing of death and maternal conditions. We have also demonstrated that it is feasible to convert an existing perinatal
mortality classification system to one which is globally comparable and can inform policy-makers internationally.http://www.who.int/bulletin/enam2019Afrikaan
Use of oxygen-loaded nanobubbles to improve tissue oxygenation: bone-relevant mechanisms of action and effects on osteoclast differentiation
Gas-loaded nanobubbles have potential as a method of oxygen delivery to increase tumour oxygenation and therapeutically alleviate tumour hypoxia. However, the mechanism(s) whereby oxygen-loaded nanobubbles increase tumour oxygenation are unknown; with their calculated oxygen-carrying capacity being insufficient to explain this effect. Intra-tumoural hypoxia is a prime therapeutic target, at least partly due to hypoxia-dependent stimulation of the formation and function of bone-resorbing osteoclasts which establish metastatic cells in bone. This study aims to investigate potential mechanism(s) of oxygen delivery and in particular the possible use of oxygen-loaded nanobubbles in preventing bone metastasis via effects on osteoclasts. Lecithin-based nanobubbles preferentially interacted with phagocytic cells (monocytes, osteoclasts) via a combination of lipid transfer, clathrin-dependent endocytosis and phagocytosis. This interaction caused general suppression of osteoclast differentiation via inhibition of cell fusion. Additionally, repeat exposure to oxygen-loaded nanobubbles inhibited osteoclast formation to a greater extent than nitrogen-loaded nanobubbles. This gas-dependent effect was driven by differential effects on the fusion of mononuclear precursor cells to form pre-osteoclasts, partly due to elevated potentiation of RANKL-induced ROS by nitrogen-loaded nanobubbles. Our findings suggest that oxygen-loaded nanobubbles could represent a promising therapeutic strategy for cancer therapy; reducing osteoclast formation and therefore bone metastasis via preferential interaction with monocytes/macrophages within the tumour and bone microenvironment, in addition to known effects of directly improving tumour oxygenation
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