Water droplet evaporation in varied gravity and electric fields

Sessile water droplet evaporation in varied gravity and electric fields has been experimentally studied. Specifically, the influences of gravity and electric fields are investigated in the context of the heat flux distribution beneath the droplets, as well as the droplet mechanics and resulting shapes. Experimental testing was carried out during a European Space Agency (ESA) Parabolic Flight Campaign (PFC 66). The droplets tested evaporated with a pinned contact line, a single wettability condition, and varied droplet volume and substrate heat flux. The peak heat transfer was located at the contact line for all cases. The peak heat flux, average heat flux, and droplet evaporation rate were shown to vary strongly with gravity, with higher values noted for hypergravity conditions and lower values in microgravity conditions. The droplet thermal inertia was shown to play a significant role, with larger droplets taking more time to reach thermal equilibrium during the parabolic testing period. No significant impact of the electric field on the droplet evaporation was noted for these test conditions.

Validation of Three Rapid Screening Methods for Detection of Verotoxin-Producing Escherichia coli in Foods: Interlaboratory Study

An interlaboratory study was conducted for the validation of 3 methods for the detection of all verotoxin-producing Escherichia coli (VTEC) in foods. The methods were a multi-analyte 1-step lateral flow immunoassay (LFIA) for detection of E. coli O157 and verotoxin (VT); an enzyme-linked immunosorbent assay targeted against VT1, VT2, and VT2c (VT-ELISA); and a polymerase chain reaction (PCR) method for detection of VT genes (VT-PCR). Aliquots (25 g or 25 mL) of 4 food types (raw minced [ground] beef, unpasteurized milk, unpasteurized apple juice [cider], and salami) were individually inoculated with low numbers (<9 to 375 cells/25 g) of 6 test strains of E. coli (serogroups O26, O103, O111, O145, and O157) with differing VT-producing capabilities. Five replicates for each test strain and 5 uninoculated samples were prepared for each food type. Fourteen participating laboratories analyzed samples using the LFIA, 9 analyzed the samples by ELISA, and 9 by PCR. The LFIA for O157 and VT had a specificity (correct identification of negative samples) of 92 and 94%, respectively, and a sensitivity (correct identification of positive samples) of 94 and 55%, respectively. The VT-ELISA and VT-PCR

Correction: Mitochondrial oxodicarboxylate carrier deficiency is associated with mitochondrial DNA depletion and spinal muscular atrophy-like disease

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Cerebral-placental-uterine ratio as novel predictor of late fetal growth restriction: prospective cohort study

OBJECTIVE

Fetal growth restriction (FGR) is a major risk factor for stillbirth and most commonly arises from uteroplacental insufficiency. Despite clinical examination and third-trimester fetal biometry, cases of FGR often remain undetected antenatally. Placental insufficiency is known to be associated with altered blood flow resistance in maternal, placental and fetal vessels. The aim of this study was to evaluate the performance of individual and combined Doppler blood flow resistance measurements in the prediction of term small-for-gestational age and FGR.

METHODS

This was a prospective study of 347 nulliparous women with a singleton pregnancy at 36 weeks' gestation in which fetal growth and Doppler measurements were obtained. Pulsatility indices (PI) of the uterine arteries (UtA), umbilical artery (UA) and fetal vessels were analyzed, individually and in combination, for prediction of birth weight < 10^th , < 5^th and < 3^rd centiles. Doppler values were converted into centiles or multiples of the median (MoM) for gestational age. The sensitivities, positive and negative predictive values and odds ratios (OR) of the Doppler parameters for these birth weights at ∼ 90% specificity were assessed. Additionally, the correlations between Doppler measurements and other measures of placental insufficiency, namely fetal growth velocity and neonatal body fat measures, were analyzed.

RESULTS

The Doppler combination most strongly associated with placental insufficiency was a newly generated parameter, which we have named the cerebral-placental-uterine ratio (CPUR). CPUR is the cerebroplacental ratio (CPR) (middle cerebral artery PI/UA-PI) divided by mean UtA-PI. CPUR MoM detected FGR better than did mean UtA-PI MoM or CPR MoM alone. At ∼ 90% specificity, low CPUR MoM had sensitivities of 50% for birth weight < 10^th centile, 68% for < 5^th centile and 89% for < 3^rd centile. The respective sensitivities of low CPR MoM were 26%, 37% and 44% and those of high UtA-PI MoM were 34%, 47% and 67%. Low CPUR MoM was associated with birth weight < 10^th centile with an OR of 9.1, < 5^th centile with an OR of 17.3 and < 3^rd centile with an OR of 57.0 (P < 0.0001 for all). CPUR MoM was also correlated most strongly with fetal growth velocity and neonatal body fat measures, as compared with CPR MoM or UtA-PI MoM alone.

CONCLUSIONS

In this cohort, a novel Doppler variable combination, the CPUR (CPR/UtA-PI), had the strongest association with indicators of placental insufficiency. CPUR detected more cases of FGR than did any other Doppler parameter measured. If these results are replicated independently, this new parameter may lead to better identification of fetuses at increased risk of stillbirth that may benefit from obstetric intervention. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.

SURF1 knockout cloned pigs: Early onset of a severe lethal phenotype

Leigh syndrome (LS) associated with cytochrome c oxidase (COX) deficiency is an early onset, fatal mitochondrial encephalopathy, leading to multiple neurological failure and eventually death, usually in the first decade of life. Mutations in SURF1, a nuclear gene encoding a mitochondrial protein involved in COX assembly, are among the most common causes of LS. LSSURF1 patients display severe, isolated COX deficiency in all tissues, including cultured fibroblasts and skeletal muscle. Recombinant, constitutive SURF1-/- mice show diffuse COX deficiency, but fail to recapitulate the severity of the human clinical phenotype. Pigs are an attractive alternative model for human diseases, because of their size, as well as metabolic, physiological and genetic similarity to humans. Here, we determined the complete sequence of the swine SURF1 gene, disrupted it in pig primary fibroblast cell lines using both TALENs and CRISPR/Cas9 genome editing systems, before finally generating SURF1-/- and SURF1-/+ pigs by Somatic Cell Nuclear Transfer (SCNT). SURF1-/- pigs were characterized by failure to thrive, muscle weakness and highly reduced life span with elevated perinatal mortality, compared to heterozygous SURF1-/+ and wild type littermates. Surprisingly, no obvious COX deficiency was detected in SURF1-/- tissues, although histochemical analysis revealed the presence of COX deficiency in jejunum villi and total mRNA sequencing (RNAseq) showed that several COX subunit-encoding genes were significantly down-regulated in SURF1-/- skeletal muscles. In addition, neuropathological findings, indicated a delay in central nervous system development of newborn SURF1-/- piglets. Our results suggest a broader role of sSURF1 in mitochondrial bioenergetics.

Gastrointestinal parasites in Ugandan cancer patients: a retrospective departmental review

Of all cancer patients, 28% had gastrointestinal parasites of medical importance.

Malignant melanoma arising in sebaceous naevus (of Jadassohn): a case report

Sebaceous naevus are associated with malignant transformation. They commonly occur in the head and neck region and are associated with malignant transformation into basal cell and squamous cell carcinomas. This case report describes a case of a malignant melanoma arising from a longstanding sebaceous naevus.

Foetal "black bone" MRI: utility in assessment of the foetal spine

OBJECTIVE

Foetal CT has recently been added to the foetal imaging armamentarium, but this carries with it the risks of ionizing radiation, both to the mother and the foetus. Foetal "black bone" MRI is a new technique that allows assessment of the foetal skeleton without the risk of exposure to ionizing radiation and is a potential new sequence in foetal MRI examination.

METHODS

Retrospective review of all foetal MRI studies over the past 4- to 5-year period identified 36 cases where susceptibility weighted imaging was used. Cases were selected from this group to demonstrate the potential utility of this sequence.

RESULTS

This sequence is most frequently useful not only in the assessment of spinal abnormalities, most commonly the bony abnormalities in myelomeningocele, but also in cases of scoliosis, segmentation anomalies and sacrococcygeal teratoma.

CONCLUSION

Although the utility of this sequence is still being evaluated, it provides excellent contrast between the mineralized skeleton and surrounding soft tissues compared with standard half Fourier acquisition single-shot turbo-spin echo sequences. Further assessment is required to determine whether black bone MRI can more accurately evaluate the level of bony defect in spina bifida aperta, an important prognostic factor. Potential further uses include the assessment of skeletal dysplasias, evaluation of the skull base and craniofacial skeleton in certain congenital anomalies and the post-mortem evaluation of the foetal skeleton potentially obviating the need for necropsy.

ADVANCES IN KNOWLEDGE

Foetal black bone MRI can be performed using susceptibility weighted imaging and allows better demonstration of the mineralized skeleton compared with standard sequences.

Sonographic 'molar tooth' sign in the diagnosis of Joubert syndrome

The characteristic imaging finding common to Joubert syndrome and related disorders is the 'molar tooth' sign. The prenatal diagnosis of Joubert syndrome using both ultrasound and fetal magnetic resonance imaging (MRI) in families with an affected child has been reported previously. We report two cases in which the molar tooth sign was identified by sonography at 26 + 4 weeks and at 20 + 6 weeks, respectively, prior to fetal MRI or genetic testing. In both cases the finding was subsequently confirmed on fetal MRI. As definitive prenatal genetic testing may not be conclusive in Joubert syndrome, the ability to identify the molar tooth sign sonographically before 24 weeks provides a valuable adjunct to prenatal diagnosis.

Prevalence of contagious pustular dermatitis (orf) in six million lambs at slaughter: a three-year study

In the three years from October 1979 to September 1982 over 6.3 million lambs were processed in two meat works and of these 0.5% had lesions of contagious pustular dermatitis (CPD). The proportion of lambs affected was highest in the months of December and January when up to 2.2% of the lambs slaughtered had lesions of CPD. On average 13.4% of a consignment (referred to as a line) of lambs showing evidence of CPD were affected. The total lambs in affected lines constituted 4.1% of the total slaughtered. If it was decided to reject for slaughter lines with CPD, approximately 1 1/4 million lambs would be returned to farms each year. It was concluded that such a policy would be unlikely to substantially reduce the level of infection in meat workers.

A longitudinal serological survey of parvovirus infection in dogs

Serum samples collected from dogs routinely presented at a clinic between June 1974 and October 1980 were tested for the presence of haemagglutination inhibition (HI) titres to canine parvovirus. The first positive titre (>1:320) was demonstrated in serum collected in October 1979. The first confirmed clinical case of canine parvovirus enteritis was diagnosed by the authors in July 1979. In addition, between 1st December 1980 and 1st March 1981, serum samples were collected from 106 healthy dogs which were presented for canine parvovirus vaccination for the first time. Twenty-four dogs (approx. 23%) showed HI titres >1:320 indicating probable previous canine parvovirus infection. Therefore approx. 80% of dogs in the clinic area were at risk at that time and vaccination should have protected them from infection.

A high-precision apparatus for the characterization of thermal interface materials

An apparatus has been designed and constructed to characterize thermal interface materials with unprecedented precision and sensitivity. The design of the apparatus is based upon a popular implementation of ASTM D5470 where well-characterized meter bars are used to extrapolate surface temperatures and measure heat flux through the sample under test. Measurements of thermal resistance, effective thermal conductivity, and electrical resistance can be made simultaneously as functions of pressure or sample thickness. This apparatus is unique in that it takes advantage of small, well-calibrated thermistors for precise temperature measurements (+/-0.001 K) and incorporates simultaneous measurement of electrical resistance of the sample. By employing precision thermometry, low heater powers and minimal temperature gradients are maintained through the meter bars, thereby reducing uncertainties due to heat leakage and changes in meter-bar thermal conductivity. Careful implementation of instrumentation to measure thickness and force also contributes to a low overall uncertainty. Finally, a robust error analysis provides uncertainties for all measured and calculated quantities. Baseline tests were performed to demonstrate the sensitivity and precision of the apparatus by measuring the contact resistance of the meter bars in contact with each other as representative low specific thermal resistance cases. A minimum specific thermal resistance of 4.68x10(-6) m(2) K/W was measured with an uncertainty of 2.7% using a heat transfer rate of 16.8 W. Additionally, example measurements performed on a commercially available graphite thermal interface material demonstrate the relationship between thermal and electrical contact resistance. These measurements further demonstrate repeatability in measured effective thermal conductivity of approximately 1%.

Fluvastatin and lovastatin inhibit granulocyte macrophage-colony stimulating factor-stimulated human eosinophil adhesion to inter-cellular adhesion molecule-1 under flow conditions

BACKGROUND

Eosinophil accumulation in the lung is an important feature of airway inflammation in asthma. There is therefore much interest in developing novel therapies to prevent this process. Accumulating evidence suggests that statins have anti-inflammatory properties, including inhibition of leucocyte accumulation. We therefore assessed the ability of five statins to inhibit human eosinophil adhesion to recombinant human inter-cellular adhesion molecule (rhICAM)-1 under physiologically relevant flow conditions.

METHODS

Purified eosinophils were pre-treated with a panel of statins before elucidation of the adhesion profiles of resting and granulocyte macrophage-colony stimulating factor (GM-CSF)-stimulated cells to rhICAM-1-coated microchannels at a flow rate of 0.5 dynes/cm(2). Images were recorded in real-time at 1 min intervals and analysed using Ducocell software.

RESULTS

Fluvastatin and lovastatin (both 10 nm) significantly inhibited GM-CSF-stimulated eosinophil adhesion to rhICAM-1 after 2 min (34.4+/-3.0% inhibition and 37.8+/-12.6% inhibition, respectively, n=4, P<0.05) but had no significant inhibitory effect on unstimulated eosinophil adhesion. Mevastatin, simvastatin, and pravastatin (all 10 nm) had no significant effect on GM-CSF-stimulated eosinophil adhesion to rhICAM-1. A concentration range of fluvastatin and lovastatin inhibited GM-CSF stimulated eosinophil adhesion with significant (P<0.05) inhibition observed at low concentrations of 1 nm for both drugs. Mevalonate (100 nm) reversed fluvastatin-mediated but not lovastatin-mediated inhibition of eosinophil adhesion.

CONCLUSIONS

Inhibition of eosinophil adhesion to ICAM-1 by fluvastatin and lovastatin under physiological shear stress represent novel actions by these drugs that may inform the development of anti-inflammatory therapy for allergic disease.

Repeat sequences from complex ds DNA viruses can be used as minisatellite probes for DNA fingerprinting

In a search for new fingerprinting probes for use with sheep, repeat sequences derived from five poxviruses, an iridovirus and a baculovirus were screened against DNA from sheep pedigrees. Probes constructed from portions of the parapox viruses, orf virus and papular stomatitis virus and the baculovirus from the alfalfa looper, Autographa californica, nuclear polyhedrosis virus all gave fingerprint patterns. Probes from three other poxviruses and an iridovirus did not give useful banding patterns.

Identification and partial characterisation of a new Lagovirus in Australian wild rabbits

Rabbit Haemorrhagic Disease Virus (RHDV) is widely used in Australia to control feral rabbit populations. Before RHDV was released on the Australian continent in 1996, antibodies cross-reacting in RHDV specific ELISAs were found in Australian wild rabbits, leading to the hypothesis that a non-pathogenic calicivirus had been circulating in rabbit populations in Australia, potentially providing some level of cross-immunoprotection to RHDV infection. For the detection of this putative virus, a universal lagovirus PCR test was developed to screen a variety of different tissues of wild caught rabbits. We identified a new lagovirus in the intestinal tissues of three apparently healthy young wild rabbits. Quantitative Real Time PCR analysis revealed high concentrations of viral RNA in intestinal tissues and suggests a faecal-oral mode of transmission. Genome organisation and phylogenetic analysis following the sequencing of the entire viral genome revealed a new member of the genus Lagovirus within the family Caliciviridae.

Would offering rapid point-of-care testing or non-invasive methods improve uptake of HIV testing among high-risk genitourinary medicine clinic attendees? A patient perspective

While most genitourinary (GU) medicine clinics achieve a high uptake for testing HIV in new patients, they may still miss testing those at highest risk. Point-of-care testing (POCT) and salivary samples are acceptable and feasible but have not yet been shown to increase uptake among high-risk patients (HRP). This study aimed to describe reasons why HRP decline HIV testing and whether offering POCT along with standard testing would increase the uptake of testing HIV in two London GU medicine clinics. Anonymous self-administered questionnaires were offered to all new and rebooked patients. Eight hundred and ninety-nine questionnaires were analysed of which 598 were HRP. Uptake of HIV testing was 77.1 % among HRP and 65.8% among the rest. A total of 51.1 % of HRP who declined HIV testing said they would be more likely to accept a POCT and 32.8% a salivary test. Introduction of rapid POCT for HIV would increase patient's choice and may increase the likelihood of HRP accepting an HIV test.

Behavioural characterisation of the alpha-mannosidosis guinea pig

alpha-Mannosidosis is a lysosomal storage disorder resulting from a functional deficiency of the lysosomal enzyme alpha-mannosidase. This deficiency results in the accumulation of various oligosaccharides in the lysosomes of affected individuals, causing somatic pathology and progressive neurological degeneration that results in cognitive deficits, ataxia, and other neurological symptoms. We have a naturally occurring guinea pig model of this disease which exhibits a deficiency of lysosomal alpha-mannosidase and has a similar clinical presentation to human alpha-mannosidosis. Various tests were developed in the present study to characterise and quantitate the loss of neurological function in alpha-mannosidosis guinea pigs and to follow closely the progression of the disease. General neurological examinations showed progressive differences in alpha-mannosidosis animals from approximately 1 month of age. Significant differences were observed in hind limb gait width from 2 months of age and significant cognitive (memory and learning) deficits were observed from 3 months of age. Evoked response tests showed an increase in somatosensory P1 peak latency in alpha-mannosidosis guinea pigs from approximately 2 months of age, as well as progressive hearing loss using auditory brainstem evoked responses. The alpha-mannosidosis guinea pig therefore appears to exhibit many of the characteristics of the human disease, and will be useful in evaluating therapies for treatment of central nervous system pathology.

Chlamydia trachomatis and Neisseria gonorrhoeae infection and the sexual behaviour of men who have sex with men

BACKGROUND

Rates of bacterial sexually transmitted infections (STIs) continue to rise among men who have sex with men (MSM) in the UK.

OBJECTIVE

To evaluate factors associated with Chlamydia trachomatis and Neisseria gonorrhoeae among MSM attending a genitourinary medicine clinic in inner London.

STUDY DESIGN

599 MSM undergoing testing for STIs were recruited. Specimens for ligase chain reaction (LCR), strand displacement amplification (SDA) assay and culture were collected from the pharynx, urethra and rectum for the detection of C trachomatis and N gonorrhoeae. Details regarding demographics, symptoms, signs and sexual behaviour were recorded. Associations of these factors with each infection were tested, adjusting for other risk factors.

RESULTS

The prevalence of C trachomatis and N gonorrhoeae was 11.0% and 16.0%, respectively. LCR and SDA performed well for the detection of C trachomatis and N gonorrhoeae from urethra and rectum. Using either method, compared with our current testing policy, over 18% of those with C trachomatis and N gonorrhoeae would not have had their infection diagnosed or treated. Age, sexual behaviour, urethral and rectal symptoms and signs were strongly associated with both infections. A total of 33.7% of men reported at least one episode of unprotected anal intercourse in the previous month. Men reporting multiple episodes were markedly more likely to be HIV positive.

CONCLUSION

The prevalence of infection, rates of partner acquisition and unprotected anal intercourse reported among these MSM are alarming. Improved detection of C trachomatis and N gonorrhoeae using nucleic acid amplification tests has major public health implications for STI and possibly HIV transmission in this population.