Simultaneous repolarization of two 10-Gb/s polarization-scrambled wavelength channels using a mutual-injection-locked laser diode

Author name used in this publication: W. H. ChungAuthor name used in this publication: P. K. A. WaiAuthor name used in this publication: H. Y. TamAuthor name used in this publication: M. S. Demokan2002-2003 > Academic research: refereed > Publication in refereed journalVersion of RecordPublishe

All-optical bit-error monitoring system using cascaded inverted wavelength converter and optical NOR gate

Author name used in this publication: Demokan, M. S.Author name used in this publication: Wai, P. K. A.2002-2003 > Academic research: refereed > Publication in refereed journalVersion of RecordPublishe

Comparison of screening strategies to improve the diagnosis of latent tuberculosis infection in the HIV-positive population: a cohort study

Background HIV is the most important risk factor for progression of latent tuberculosis infection (LTBI) to active tuberculosis (TB). Detection and treatment of LTBI is necessary to reduce the increasing burden of TB in the UK, but a unified LTBI screening approach has not been adopted. Objective To compare the effectiveness of a TB risk-focused approach to LTBI screening in the HIV-positive population against current UK National Institute for Health and Clinical Excellence (NICE) guidance. Design Prospective cohort study. Setting Two urban HIV treatment centres in London, UK. Participants 114 HIV-infected individuals with defined TB risk factors were enrolled prospectively as part of ongoing studies into HIV and TB co-infection. Outcome measures The yield and case detection rate of LTBI cases within the research study were compared with those generated by the NICE criteria. Results 17/114 (14.9%, 95% CI 8.3 to 21.5) had evidence of LTBI. Limiting screening to those meeting NICE criteria for the general population (n=43) would have detected just over half of these, 9/43 (20.9%, 95% CI 8.3 to 33.5) and those meeting criteria for HIV co-infection (n=74) would only have captured 8/74(10.8%, 95% CI 3.6 to 18.1) cases. The case detection rates from the study and NICE approaches were not significantly different. LTBI was associated with the presence of multiple TB risk factors (p=0.002). Conclusion Adoption of a TB risk-focused screening algorithm that does not use CD4 count stratification could prevent more cases of TB reactivation, without changing the case detection rate. These findings should be used to inform a large-scale study to create unified guidelines

Demonstration of an all-optical switch by use of a multiwavelength mutual injection-locked laser diode

Author name used in this publication: P. K. A. WaiAuthor name used in this publication: L. F. K. LuiAuthor name used in this publication: W. H. ChungAuthor name used in this publication: H. Y. TamAuthor name used in this publication: M. S. Demokan2002-2003 > Academic research: refereed > Publication in refereed journalVersion of RecordPublishe

Is Early Puberty Triggered by Catch-Up Growth Following Undernutrition?

Undernutrition during fetal and postnatal life is still a major problem in many low- and middle-income countries. Even in high-income countries malnutrition may exist in cases of intrauterine growth retardation, as well as in chronic conditions such as anorexia nervosa and inflammatory bowel disease. Children adopted from developing countries are often chronically malnourished. Nutritional rehabilitation, resulting in catch-up growth, is often complicated by influences originating in fetal life as well as during postnatal growth. This may result in hormonal and metabolic changes as well as alterations in pubertal development. The present review focuses on fetal, postnatal and fetal-postnatal undernutrition and subsequent catch-up growth as well as catch-up growth in relation to pubertal development. Catch-up growth in children can be associated with early puberty following fetal or combined fetal-postnatal undernutrition. However, early puberty does not seem to occur following catch-up growth after isolated postnatal undernutrition. Gonadotropins have been reported to be elevated in prepubertal adopted girls as well as during catch-up growth in animals. Even if other factors may contribute, linear catch-up growth seems to be associated with the timing of pubertal development. The mechanisms behind this are still unknown. Future research may elucidate how to carry out nutritional rehabilitation without risk for early pubertal development

dsRNA expression in the mouse elicits RNAi in oocytes and low adenosine deamination in somatic cells

Double-stranded RNA (dsRNA) can enter different pathways in mammalian cells, including sequence-specific RNA interference (RNAi), sequence-independent interferon (IFN) response and editing by adenosine deaminases. To study the routing of dsRNA to these pathways in vivo, we used transgenic mice ubiquitously expressing from a strong promoter, an mRNA with a long hairpin in its 3′-UTR. The expressed dsRNA neither caused any developmental defects nor activated the IFN response, which was inducible only at high expression levels in cultured cells. The dsRNA was poorly processed into siRNAs in somatic cells, whereas, robust RNAi effects were found in oocytes, suggesting that somatic cells lack some factor(s) facilitating siRNA biogenesis. Expressed dsRNA did not cause transcriptional silencing in trans. Analysis of RNA editing revealed that a small fraction of long dsRNA is edited. RNA editing neither prevented the cytoplasmic localization nor processing into siRNAs. Thus, a long dsRNA structure is well tolerated in mammalian cells and is mainly causing a robust RNAi response in oocytes

Nature doesn't judge you – how urban nature supports young people's mental health and wellbeing in a diverse UK city

Reviewed research reveals a lack of young people's voices articulating if and how urban nature supports their mental health and wellbeing. This paper presents qualitative research with young multi-ethnic urban residents living in a northern UK city and offers an important counter-narrative to the pervasive notion of childhood nature-deficit disorder. Using interviews and creative arts workshops, we explored the value of urban nature for the mental health and wellbeing of 24 young people aged 17–27 years, 9 of whom had lived experience of mental health difficulties. Trees, water, open spaces and views were frequently experienced nature typologies offering benefits. Deteriorating landscapes, young people's shifting identities and perceived time pressures disrupted support. Young people expressed how urban nature encounters were experienced as accepting and relational, offering a: stronger sense of self; feelings of escape; connection and care with the human and non-human world

Risk of adverse outcomes in patients with underlying respiratory conditions admitted to hospital with COVID-19:a national, multicentre prospective cohort study using the ISARIC WHO Clinical Characterisation Protocol UK

Background Studies of patients admitted to hospital with COVID-19 have found varying mortality outcomes associated with underlying respiratory conditions and inhaled corticosteroid use. Using data from a national, multicentre, prospective cohort, we aimed to characterise people with COVID-19 admitted to hospital with underlying respiratory disease, assess the level of care received, measure in-hospital mortality, and examine the effect of inhaled corticosteroid use. Methods We analysed data from the International Severe Acute Respiratory and emerging Infection Consortium (ISARIC) WHO Clinical Characterisation Protocol UK (CCP-UK) study. All patients admitted to hospital with COVID-19 across England, Scotland, and Wales between Jan 17 and Aug 3, 2020, were eligible for inclusion in this analysis. Patients with asthma, chronic pulmonary disease, or both, were identified and stratified by age (<16 years, 16–49 years, and ≥50 years). In-hospital mortality was measured by use of multilevel Cox proportional hazards, adjusting for demographics, comorbidities, and medications (inhaled corticosteroids, short-acting β-agonists [SABAs], and long-acting β-agonists [LABAs]). Patients with asthma who were taking an inhaled corticosteroid plus LABA plus another maintenance asthma medication were considered to have severe asthma. Findings 75 463 patients from 258 participating health-care facilities were included in this analysis: 860 patients younger than 16 years (74 [8·6%] with asthma), 8950 patients aged 16–49 years (1867 [20·9%] with asthma), and 65 653 patients aged 50 years and older (5918 [9·0%] with asthma, 10 266 [15·6%] with chronic pulmonary disease, and 2071 [3·2%] with both asthma and chronic pulmonary disease). Patients with asthma were significantly more likely than those without asthma to receive critical care (patients aged 16–49 years: adjusted odds ratio [OR] 1·20 [95% CI 1·05–1·37]; p=0·0080; patients aged ≥50 years: adjusted OR 1·17 [1·08–1·27]; p<0·0001), and patients aged 50 years and older with chronic pulmonary disease (with or without asthma) were significantly less likely than those without a respiratory condition to receive critical care (adjusted OR 0·66 [0·60–0·72] for those without asthma and 0·74 [0·62–0·87] for those with asthma; p<0·0001 for both). In patients aged 16–49 years, only those with severe asthma had a significant increase in mortality compared to those with no asthma (adjusted hazard ratio [HR] 1·17 [95% CI 0·73–1·86] for those on no asthma therapy, 0·99 [0·61–1·58] for those on SABAs only, 0·94 [0·62–1·43] for those on inhaled corticosteroids only, 1·02 [0·67–1·54] for those on inhaled corticosteroids plus LABAs, and 1·96 [1·25–3·08] for those with severe asthma). Among patients aged 50 years and older, those with chronic pulmonary disease had a significantly increased mortality risk, regardless of inhaled corticosteroid use, compared to patients without an underlying respiratory condition (adjusted HR 1·16 [95% CI 1·12–1·22] for those not on inhaled corticosteroids, and 1·10 [1·04–1·16] for those on inhaled corticosteroids; p<0·0001). Patients aged 50 years and older with severe asthma also had an increased mortality risk compared to those not on asthma therapy (adjusted HR 1·24 [95% CI 1·04–1·49]). In patients aged 50 years and older, inhaled corticosteroid use within 2 weeks of hospital admission was associated with decreased mortality in those with asthma, compared to those without an underlying respiratory condition (adjusted HR 0·86 [95% CI 0·80−0·92]). Interpretation Underlying respiratory conditions are common in patients admitted to hospital with COVID-19. Regardless of the severity of symptoms at admission and comorbidities, patients with asthma were more likely, and those with chronic pulmonary disease less likely, to receive critical care than patients without an underlying respiratory condition. In patients aged 16 years and older, severe asthma was associated with increased mortality compared to non-severe asthma. In patients aged 50 years and older, inhaled corticosteroid use in those with asthma was associated with lower mortality than in patients without an underlying respiratory condition; patients with chronic pulmonary disease had significantly increased mortality compared to those with no underlying respiratory condition, regardless of inhaled corticosteroid use. Our results suggest that the use of inhaled corticosteroids, within 2 weeks of admission, improves survival for patients aged 50 years and older with asthma, but not for those with chronic pulmonary disease