UV-Vis detection of E. coli 0157:H7 using Vitis vinifera and Musa paradaisica modified Au-NPs.

Herein, we demonstrate the simple one-pot novel green synthesis of gold nanoparticles (Au-NPs) functionalised with a combination of banana peel (Musa paradaisica) and grape (Vitis vinifera) fruit extracts. The reaction mixture of aqueous gold chloride, banana peel and grape extracts revealed a purple colour after a reaction time of one hour, an indication of the presence and the successful synthesis of gold nanoparticles. The optical and structural properties of the green synthesized nanoparticles were analysed using Ultraviolet-Visible spectroscopy (UV-Vis) and Fourier Transform Infrared Spectroscopy (FTIR) while their surface morphology was determined using X-Ray Diffraction (XRD), High-Resolution Transmission Microscopy (HRTEM) and Small Angle X-Ray (SAX). Furthermore, a quick and simple surface plasmon resonance (SPR) study in the form of an optical sensor for the detection of Escherichia coli 0157:H7 strain was also achieved using UV-Vis. The obtained limit of detection (LOD) value for SPR for the GBPE|Au-NPs|GCE-based system was found to be 1 × 102 CFU/mL, a value well in the range for detection in seawater.•Green synthesis of gold nanoparticles (Au-NPs) was functionalised using banana peel (Musa paradaisica) and grape (Vitis vinifera) fruit extracts as capping and stabilizing agents.•Structural characterization of the Au-NPs was achieved using Ultraviolet-Visible spectroscopy (UV-Vis) and Fourier Transform Infrared Spectroscopy (FTIR) while their surface morphology was determined using X-Ray Diffraction (XRD), High-Resolution Transmission Microscopy (HRTEM) and Small Angle X-Ray (SAX).•The green synthesized Au-NPs were used to detect Escherichia coli 0157:H7 (E. coli 0157:H7) strain using Ultraviolet-Visible spectroscopy (UV-Vis) where the surface plasmon resonance (SPR) was studied.

A green synthesis of zinc oxide nanoparticles using Musa Paradisiaca and Rooibos extracts.

This study describes the single pot synthesis of zinc oxide nanoparticles (ZnO NPs) using a mixture of Aspalathus linearis and Musa paradisiaca for use against the fungi Candida albicans. These nanoparticles are known to be one of the most multifunctional inorganic nanoparticles with effective antifungal and antibacterial activity. The synthesized ZnONPs were characterized by a peak at 290 nm in the UV-vis spectrum while HRSEM confirmed rod-shaped nanoparticles. The FTIR data clearly revealed that the extracts contained -OH  functional groups whose role was capping agents during the nanoparticle synthesis. This study also found that the purity of the green synthesised ZnO NPs (GZnO NPs) was 94.4 %, 91.5 %, and 82.1 %, respectively, using XRD, HRTEM, and HRSEM-EDS. The antifungal activity of ZnONPs was tested against Candida albicans using the Kirby Bauer method. The maximum inhibition zone observed in the ZnO NPs against Candida albicans was confirmed to be 24 mm, a clear indication that the synthesized ZnO NPs have great potential to act as effective antifungal agents.•Zinc nitrate hexahydrate [Zn(NO3)2·6H2O] was used as the inorganic metal oxide precursor.•Extracts of banana (Musa paradisiaca) peel and tea leaves of Rooibos (Aspalathus linearis) infused with Buchu (Agathosma betulina) were the organic constituents used as reducing and capping agents during GZnO NPs synthesis.•Validation of the formed GZnO NPs was done using; Ultraviolet-visible spectroscopy (UV-Vis), X-ray spectroscopy (XRD), Fourier-transform Infrared Spectroscopy (FTIR), High-resolution Transmission Electron Microscopy (HRTEM) and Selected Area Electron Diffraction (SAED), and High-Resolution Scanning Electron Microscopy with Energy-Dispersive Spectroscopy (HRSEM-EDS).

Ovarian stimulation in ART - Unwinding pressing issues.

Conventional controlled ovarian stimulation (cCOS) can cause significant discomfort, including ovarian hyperstimulation syndrome (OHSS). Clearly, management of OHSS and poor responder patients requires new strategies to overcome these problems and facilitate the birth of a healthy child with the fewest stimulation cycles. Several alternative methods have been developed. Non-conventional controlled ovarian stimulation (non-cCOS) is based on low-dose stimulation regimens and is often termed "light", "soft", "mini", "minimal", "mild", "low cost", or "low dose IVF". Non-controlled ovarian stimulation therapies (non-COS) include natural cycle IVF or a mixture between non-controlled and non-cCOS, termed "modified natural IVF" or "antiestrogen/aromatase inhibitor/low dose FSH-cycles", in which cycles are monitored but not controlled. These approaches promise to reduce the physical, emotional, and financial burden of IVF therapy while maintaining acceptable pregnancy rates. Such approaches might reduce the risk of OHSS. However, the overall cost per baby increases due to the higher number of stimulation cycles required, and the inconvenience of ovum pick-up still remains. The primary focus should be to obtain several good quality blastocysts after a single cCOS cycle. Thus, adequate numbers of mature oocytes are mandatory. What is more difficult and expensive for patients: several non-COS/non-cCOS cycles to obtain a baby or a single cCOS cycle with a high probability to obtain more than one child? Classic cCOS using the GnRH agonist long protocol followed by single embryo transfer (SET) at the blastocyst stage and aseptic vitrification of surplus embryos optimizes the IVF outcome. This strategy, combined with outpatient management in the case of OHSS, minimizes inconvenience and risks of OHSS. Accumulation cycles (AC) by repeated COS with subsequent freezing of blastocysts, combined with preimplantation genetic screening (PGS), is a promising new approach for low responders, especially in cases of advanced maternal age (AMA).

Opinion of obstetricians and gynaecologists on ethical issues in the practice of in-vitro fertilisation and embryo transfer in Nigeria.

The objective of this study was to bring ethical issues in the practice of in-vitro fertilisation (IVF) in Nigeria to the fore, to determine and articulate the views of Obstetricians and Gynaecologists on treatment modalities and to drive regulation of this specialised field. A plenary session was organised by The Bridge Clinic at the 2010 Society of Gynaecology and Obstetrics of Nigeria (SOGON) annual general meeting. Participants self-administered a 33-point questionnaire on their views on ethical issues in IVF. The results buttress the conclusions of an earlier publication, clearly indicating that even amongst specialised medical professionals; there are varying views which really cannot be challenged as being either right or wrong as they represent the individuals' position and his culture. Within the context of our society, ethics and morality especially as they affect patient care can and must be hinged on a code or framework which should be developed, implemented and its implementation monitored by a legally bound regulatory body for the protection of the rights and safety of our patients, their unborn children and for the integrity of our health care systems.

Stakeholders' views on ethical issues in the practice of in-vitro fertilisation and embryo transfer in Nigeria.

The provision of IVF for the specialized treatment of infertility has grown very rapidly in Nigeria in recent times, especially within the private sector. The objective of this study was to document the views of key stakeholders regarding salient ethical issues relating to the practice of in-vitro fertilisation (IVF) in Nigeria. A think-tank session was convened with participants drawn from different backgrounds and disciplines to deliberate on ethical issues in IVF. Ten key issues were discussed at this inaugural session. It was unanimously agreed that there are no right or wrong answers when considering the ethics and morality of IVF as these are principally dependent on choice and circumstances. However within the legal and socio-cultural dictates of the Nigerian society, right and wrong may be clearly determined on some issues. With the expansion of the IVF industry and technology in Nigeria, the need to address related ethical issues have become paramount. The forum recommended that it is important that regulatory guidelines are put in place to regulate the practice of IVF in Nigeria and to protect patients' rights and safety.

Experience with conscious sedation for oocyte retrieval in Nigeria.

Conscious sedation is the most common method of pain relief used during ultrasound-directed transvaginal follicle aspiration (UDFA) for in-vitro fertilisation/embryo transfer (IVF/ETI). It is associated with minimal risks and facilitates early discharge following UDFA. The aim of this study was to assess clients' pain experience, acceptance of conscious sedation and correlates of pain during oocyte retrieval for in vitro fertilisation (IVF) at The Bridge Clinic, Port Harcourt. It was a cross-sectional survey conducted between May 1 and October 31 2004. Pain was assessed using a 100 mm visual analog scale (VAS). Clients' pain experience and correlates were evaluated using Pearson's correlation and the student's t-test. The mean pain score was low and the duration of the procedure did not significantly affect the severity of pain felt by the client. Most (69.0%) clients would prefer the same sedation and analgesia for any subsequent procedure. Conscious sedation and analgesia are one of several methods used to relieve pain during oocyte retrieval in IVF procedures. The information in this study is of value when considering the management of pain in patients undergoing oocyte retrieval procedures.

Prevalence of refractive error and attitude to spectacle use among drivers of public institutions in Ibadan, Nigeria.

BACKGROUND: High rate of motor vehicle accidents' have been associated with poor vision. Studies on drivers from elsewhere other than health institutions have found abnormal visual acuities. The aim of this study is to determine prevalence of refractive errors and the attitude to spectacle wear among drivers of public institutions studied. METHODS: A cross sectional population study of all 99 motor vehicle drivers from the College of Medicine, University of Ibadan and University College Hospital (UCH) Ibadan between December 2003 and January 2004. RESULTS: The ninety-nine motor vehicle drivers in the study comprised of 67 (67.7%) from the College of Medicine, and 32 (32.3%) from the UCH. All were males, aged 38 to 60 years, mean 50.1 +/- (SD= 4.8 years). Proportion of drivers with refractive errors was 16.7% (95% CI, 16.6-16.8) but only 56.3% of these wear glasses while driving (others did not including 3 out 4 who were bilaterally visually impaired without glasses). Relative frequency of RTA among drivers was 16.2%, the risk was marginally higher among drivers with refractive error (OR 1.2, 95% CI: 0.4-3.7). The commonest refractive error was simple hypermetropia present in 15 eyes. Hypermetropia was associated with increasing age of drivers (p<0.05). Majority (97.7%) of the drivers were presbyopic but only 32 (32.3%) were current wearers of spectacles. CONCLUSION: Refractive errors were present in 16.7% of drivers studied. But 43.8% of these (3 out 4 of whom were bilaterally visually impaired without glasses) do not wear corrective lenses while driving. There is need for periodic visual screening exercise and eye health education on drivers.

Live births after intracytoplasmic sperm injection in the management of oligospermia and azoospermia in Nigeria.

Intracytoplasmic sperm injection has revolutionised the management of male infertility. We report two cases that demonstrate the successful application of this technology in Nigeria in the management of both oligospermia and azoospermia. The first case relates to the treatment of a 31-year-old woman who required intracytoplasmic sperm injection of her husband's sperm for the treatment of both tubal fertility and male infertility. She had three embryos transferred on 9th June 1999 and was delivered of healthy male and female infants by caesarean section in January 2000 at 33 weeks gestation. The second case describes a 38-year-old woman who required intracytoplasmic sperm injection of the husband's surgically collected sperm for the management of azoospermia. She had two embryos transferred on 16th December 1999 and was delivered of a healthy male infant by caesarean section on 19th July 2001.

Poor acceptance rate for semen donors to a private cryobank in Nigeria.

A retrospective analysis of sixty one prospective donors who visited the cryobank in person from August 1999 to December 2001 was done. The study evaluated the acceptance rate of prospective semen donors and semen characteristics in order to assess the fertility potential of the supposedly normal population of young men. The outcome of the various screening processes--history taking, infection screening, blood grouping and Hb genotype assessment, semen analyses (pre-freeze and post-thaw), and post-quarantine (six months after production of last sample) infection--was analysed. Out of the 61 enquiries, 9 (14.8%) donors were recruited, 7 (77.8%) of whom were less than 25 years old. Fourteen (22.9%) donors had sperm concentrations greater than 60' 10(6) ml, 31 (50.8%) had motility greater than 60% and 17 (27.8%) had normal forms greater than 30%. Six (9.8%) of the donors were unable to masturbate and thus were disqualified, while only one donor (6.1%) failed to show up for a re-test after the completion of the quarantine period. Twenty one (38.2%) donors had low semen values based on the WHO reference value. We conclude that a high proportion of prospective semen donors may have suboptimal semen parameters, and that using strict criteria, poor acceptance rates for donors is observed in a semen donation programme.

Ultrasound diagnosis of the Pena Shokeir phenotype at 14 weeks of pregnancy.

This report describes the early prenatal diagnosis of the Pena Shokeir phenotype in an at-risk patient at 14 weeks' gestation. The diagnosis was based on an abnormal fetal movement profile, in association with an abnormal position of the fetal limbs. Pena Shokeir phenotype describes an inherited condition characterized by arthrogryposis and dysmorphic features as a result of fetal akinesia. It is a lethal abnormality and early diagnosis allows safer surgical methods of termination.

Fetal oxygenation at cordocentesis, maternal smoking and childhood neuro-development.

OBJECTIVE: To assess the relationship between subsequent neuro-development and measurements in small for gestational age (SGA) fetuses, including oxygenation at cordocentesis. DESIGN: A longitudinal study of a cohort of SGA fetuses using those with normal oxygenation as controls. SUBJECTS: 65 chromosomally normal children aged 12-66 months who, as fetuses, had been small for gestational age, had undergone cordocentesis and had been delivered after 32 weeks' gestation. RESULTS: Griffiths' developmental quotient (DQ) was significantly associated with fetal blood pH (r = 0.41, P = 0.0008), PO2 (r = 0.25, P = 0.047) and PCO2 (r = -0.28, P = 0.027) at cordocentesis but not with the severity of growth retardation (r = 0.18, P = 0.17). However, the significant correlations between DQ and both PO2 and PCO2 were explained by their co-correlations with pH and neither remained significant after removing the effect of pH by analysis of variance. The association between DQ and pH was still significant after removing the effect of confounding variables. Maternal smoking during pregnancy was significantly associated with DQ (F to remove = 6.89, P = 0.011) even after allowing for the effects of possible confounding variables including fetal blood pH. CONCLUSIONS: Both fetal pH at cordocentesis and maternal smoking correlate significantly with subsequent neuro-development. Further investigation into the causes of these associations is required.

Prediction of morbidity in small and normally grown fetuses by fetal heart rate variability, biophysical profile score and umbilical artery Doppler studies.

OBJECTIVE: To assess the ability of noninvasive tests of fetal wellbeing to predict hypoxic morbidity independent of fetal size. DESIGN: A prospectively planned, longitudinal, observational study. SETTING: Fetal Surveillance Unit, King's College Hospital, London. SUBJECTS: One hundred and ninety-one pregnant women with singleton pregnancies who were delivered after 32 weeks' gestation who were seen in the Fetal Surveillance Unit within seven days of delivery. INTERVENTIONS: Fetal surveillance by fetal abdominal circumference, heart rate variability (mean range), biophysical profile score and umbilical artery pulsatility index measurements. MAIN OUTCOME MEASURES: Birthweight was classified as > or < or = 2.5th centile (AGA or SGA) for gestational age and sex. Morbidity was defined as at least one of the following at birth: delivery by emergency caesarean section for fetal distress, umbilical venous blood pH less than 7.15, 5 min Apgar score less than 7 or admission to the Special Care Baby Unit (SCBU). RESULTS: Fetal abdominal circumference was the best indicator of which fetuses (n = 30) would be SGA. Fourteen of the 30 (47%) SGA fetuses had morbidity at birth and abnormal umbilical Doppler studies significantly predicted this (chi 2 = 2.93, P = 0.003). By contrast, fetal heart rate variability and the biophysical profile score did not. Twenty-seven of the 161 (17%) AGA fetuses had morbidity at birth, but this was not significantly predicted by heart rate variability, biophysical profile score or umbilical Doppler studies. CONCLUSIONS: None of the antenatal testing techniques studied predicted morbidity in normally grown fetuses but Doppler studies indicated whether a small fetus was 'sick small' or 'normal small'.

A comparison between computerised (mean range) and clinical visual cardiotocographic assessment.

OBJECTIVE: To compare computer cardiotocographic (CTG) analysis with clinical visual analysis. DESIGN: A retrospective blind comparison of the two techniques of CTG assessment. SETTING: Fetal Assessment Unit, King's College Hospital, London. SUBJECTS: One hundred CTG traces of women referred to the unit were studied; the traces were taken after 32 weeks' gestation, within 10 days of delivery and where outcome was known. INTERVENTIONS: The CTG traces were assessed both by the computer (System 8000 computerised CTG analyser, Oxford Sonicaid Ltd) and visually, by one of us. MAIN OUTCOME: Computer mean range from 0 to 80 in ms clinical visual CTG score from 0 to 80 (arbitrary units). A score < 20 is ominous; suspicious when between 20 and 30; and normal when > 30. RESULTS: There was close correlation between the computer mean range and clinical visual assessment (r = 0.78, n = 100, P = 0.001). However, there were 13 occasions where the computer classified the trace as abnormal when clinical visual assessment was normal, indicating computer false positives. All these pregnancies had normal outcomes. There were no traces where computer analysis was normal and clinical visual assessment abnormal. CONCLUSIONS: Computerised CTG analysis gives an objective assessment which agrees closely with experienced visual assessment. It also provides a number which can be used to assess the value of fetal heart rate analysis.

Fetal biochemistry in growth retardation.

A substantial proportion of fetuses with severe early onset growth retardation are chromosomally abnormal and in these cases detailed ultrasound scanning will often demonstrate the presence of fetal anatomical defects. Chromosomally normal SGA fetuses with no biochemical abnormalities are likely to be normal small fetuses and seem to develop normally. SGA fetuses with evidence of impaired placental perfusion such as altered fetal cardiovascular dynamics and disturbances in biochemical, haematological, metabolic and endocrine status are at increased of neurodevelopmental delay. Although incomplete, the data collected so far suggest the biochemical changes may be caused by reduced placental transfer of nutrients (e.g. oxygen, glucose and essential amino-acids) and subsequent reduced fetal metabolism leading to high levels of substrates (e.g. triglycerides and non-essential amino-acids) and low levels of tissue products (e.g. thyroid hormone, insulin, platelets and white cells).

Relationship between fetal acidemia at cordocentesis and subsequent neurodevelopment.

To determine whether there is a relationship between chronic fetal acidemia and subsequent neurodevelopment, a follow-up study was undertaken of 36 children with normal karyotype and morphology, who had prenatal cordocentesis for severe growth retardation. The main outcome measure was the Griffiths neurodevelopmental quotient. The children who had acidemia as fetuses (n = 13) had a significantly lower developmental quotient (mean = 91.8, SD = 6.3) than those with normal (n = 23) fetal blood pH (mean = 100.3, SD = 10.3; t = -2.68, p = 0.011). There was also a significant correlation between developmental quotient and the degree of fetal acidemia (r = 0.41, n = 36, p = 0.012). The pregnancies with acidemic fetuses had similar epidemiological characteristics to those with fetuses with a normal pH, except for a higher incidence of smoking. There was no significant correlation between the degree of growth retardation (birth weight expressed as multiples of SD from the mean for gestational age and sex) and fetal acidemia (r = -0.23, n = 36, NS) or subsequent Griffiths developmental quotient (r = -0.005, n = 36, NS). The results show an association between chronic fetal acidemia and subsequent impaired neurodevelopment. This observation suggests that future preventative interventions may be possible.

Antenatal testing to predict outcome in pregnancies with unexplained antepartum haemorrhage.

OBJECTIVE: To investigate whether Doppler studies of placental perfusion and antenatal tests for fetal hypoxia can identify reduced placental functional reserve in women with unexplained antepartum haemorrhage (APH). DESIGN: A prospective, longitudinal study. SETTING: Fetal Surveillance Unit, King's College Hospital, London. SUBJECTS: 48 women with bleeding from the genital tract after 26 weeks gestation without a clinical diagnosis of abruption or ultrasound evidence of placenta praevia. INTERVENTIONS: Fetal surveillance by Doppler measurements of the umbilical and uterine arteries, biophysical profile scoring and computerized measurement of the mean minute range of FHR variation. MAIN OUTCOME MEASURES: A poor outcome was defined by one or more of the following: (i) birthweight greater than 2SD below the normal mean for gestational age and sex, (ii) abnormal FHR pattern in labour resulting in operative delivery, (iii) umbilical vein blood pH at delivery less than 7.15, (iv) a 5-min Apgar score less than 7. RESULTS: Fifteen of the 48 pregnancies had a poor outcome; seven occurred in the 10 women delivered preterm (less than 37 weeks) and eight in the 36 women delivered between 37 and 42 weeks. Two women were delivered after 42 weeks and both infants had a good outcome. The results of Doppler studies of uterine and umbilical arteries, fetal biophysical profile or FHR variation were not significantly different between the two outcome groups. The 36 pregnancies delivered between 37 and 42 weeks were matched retrospectively for maternal age, parity and race with 36 pregnancies without APH; there was no significant difference in outcome between the women with unexplained APH and the matched comparison group. CONCLUSION: Morbidity related to unexplained APH is associated with preterm delivery rather than with damage to utero-placental function.

Ultrasound assessment of amniotic fluid volume: a comparison of the single deepest pool and amniotic fluid index to predict perinatal morbidity.

The ability of the amniotic fluid index and the single deepest pool to predict perinatal morbidity was compared in 291 high-risk singleton pregnancies without ruptured membranes or fetal renal abnormalities. A poor outcome was defined as a birth weight < -2 standard deviations, emergency Cesarean section for fetal heart rate abnormalities in labor, 5-minute Apgar score < 7, umbilical venous pH at delivery < 7.15 and admission to the special care baby unit. At least one of these parameters occurred in 71 (24%) of the 291 pregnancies. Oligohydramnios (an amniotic fluid index 5 cm (chi(2) = 2.41, p = 0.02). There was a significant correlation between amniotic fluid index and single deepest pool measurements (r = 0.83, n = 291, p < 0.0001). At the recommended cut-off values, the single deepest pool and the amniotic fluid index had sensitivities of 7% and 13%, respectively and specificities of 96% and 95% for predicting perinatal morbidity. Receiver operating characteristic curve analysis showed that these poor results were not the result of the cut-off values chosen and that the performances of the amniotic fluid index and single deepest pool were similar.

Effect of a fetal surveillance unit on admission of antenatal patients to hospital.

OBJECTIVE: To analyse the effect of a fetal surveillance unit, which undertakes a wide range of maternal and fetal tests on an outpatient or inpatient basis, on the number and length of antenatal hospital admissions. DESIGN: A comparison of the number and length of antenatal admissions six months before and five months after the opening of the unit on 1 July 1990. MAIN OUTCOME MEASURES: Admission rate, antenatal bed occupancy, and interval from admission to discharge or delivery. RESULTS: The antenatal bed occupancy rate fell by 22% from 174/100 deliveries during the six months before the unit was opened to 136/100 deliveries in the five months after it was opened. The difference in distribution of lengths of admission after the unit was opened from before was highly significant (Mann-Whitney test = 5.14, n = 752 and 679; p less than 0.0001), and this was due to shorter intervals from admission to discharge and from admission to delivery. In contrast, the antenatal admission rate did not change significantly (50/100 deliveries v 49/100 deliveries). There was no significant change in the stillbirth rate (6/1294 births v 8/1372 births; difference between rates = 0.0012, 95% confidence interval-0.0043 to 0.0067). CONCLUSION: Obstetricians are more prepared to discharge antenatal patients from hospital and, similarly, admit patients for delivery rather than for assessment if the patients are reliably monitored on an outpatient basis. If this change in practice is sustained substantial financial and social benefits will result as well as improvements in organisation, audit, teaching, and research.