Bone health in women with premature ovarian insufficiency/early menopause: a 23-year longitudinal analysis

STUDY QUESTION

What is the frequency of, and predictors for, osteoporosis, fractures, and osteoporosis management (investigation, treatment) in women with premature ovarian insufficiency (POI; menopause <40 years) and early menopause (EM; menopause 40-44years)?

SUMMARY ANSWER

Over the 23-year follow-up duration, at a mean age of 68 years, women with POI/EM had higher osteoporosis/fracture risk and prevalence, higher osteoporosis screening and anti-osteoporosis medication use compared to women with usual age menopause; increasing age was predictive of increased risk of osteoporosis/fracture and menopause hormone therapy (MHT) prior to or at study entry (aged 45-50 years) was protective.

WHAT IS KNOWN ALREADY

Women with POI/EM have increased risk of osteoporosis and fractures with limited data regarding risk factors for reduced bone density and fractures. Clinical guidelines recommend screening with dual X-ray absorptiometry (DXA) and treatment with MHT for most women with POI/EM to reduce osteoporosis and fracture risk; however, studies indicate gaps in osteoporosis knowledge, guideline uptake, and management adherence by clinicians and women.

STUDY DESIGN, SIZE, DURATION

The Australian Longitudinal Study on Women's Health is a prospective longitudinal study of Australian women. This study uses the cohort of women born between 1946 and 1951, surveyed nine times between 1996 and 2019. Data from the Australian administrative health records, including hospital admissions data (fractures, osteoporosis), Medicare Benefits Schedule (DXA), and the Pharmaceutical Benefits Scheme (PBS; MHT, anti-osteoporosis medication, available only from 2002) were linked to survey data.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Survey respondents with self-reported age of menopause were included. POI/EM was defined as menopause <45 years. T-test or chi-square were used for comparisons at baseline (P < 0.05 indicates significance). Generalized estimating equations for panel data explored predictors for the longitudinal outcomes of osteoporosis, fractures, DXA rates, MHT use, and anti-osteoporosis medication (in women with osteoporosis/fracture, from Survey 4 onwards only). Univariable regression was performed, and variables retained where P < 0.2, to form the multivariable model, and bootstrapping with 100 repetitions at 95% sampling of the original dataset to ensure robustness of results.

MAIN RESULTS AND THE ROLE OF CHANCE

Eight thousand six hundred and three women were included: 610 (7.1%) with POI/EM. Mean (SD) baseline age was 47.6 (1.45) years in the entire cohort and mean (SD) age of menopause was 38.2 (7.95) and 51.3 (3.04) years in women with POI/EM and usual age menopause, respectively (P < 0.001). Over the 23 years, of women with POI/EM, 303 (49.7%) had osteoporosis/fractures, 421 (69.0%) had DXA screening, 474 ever used MHT (77.7%), and 116 (39.1%) of those with osteoporosis/fractures used anti-osteoporosis medication. Of women with usual age menopause, 2929 (36.6%) had osteoporosis/fractures, 4920 (61.6%) had DXA screening, 4014 (50.2%) used MHT, and 964 (33.0%) of those with osteoporosis/fractures used anti-osteoporosis medication. Compared to women with menopause at age ≥45 years and after adjusting for other risk factors, women with POI/EM had increased risk of osteoporosis (odds ratio [OR] 1.37; 95% CI 1.07-1.77), fractures (OR 1.45; 1.15-1.81), DXA testing (OR 1.64; 1.42-1.90), MHT use (OR 6.87; 5.68-8.30), and anti-osteoporosis medication use (OR 1.50; 1.14-1.98). In women with POI/EM women, increasing age was associated with greater risk of osteoporosis/fracture (OR 1.09; 1.08-1.11), and MHT prior to or at study entry (aged 45-50 years), was protective (OR 0.65, 0.45-0.96). In women with POI/EM, age (OR 1.11; 1.10-1.12), fractures (OR 1.80, 1.38-2.34), current smoking (OR 0.60; 0.43-0.86), and inner (OR 0.68; 0.53-0.88) or outer regional (OR 0.63; 0.46-0.87) residential location were associated with DXA screening. In women with POI/EM, increasing age (OR 1.02; 1.01-1.02), and currently consuming alcohol (OR 1.17; 1.06-1.28), was associated with having ever used MHT. In the 299 women with POI/EM and osteoporosis/fractures, only 39.1% ever received treatment with an anti-osteoporosis medication. Increasing age (OR 1.07; 1.04-1.09) and lower BMI (OR 0.95; 0.92-0.98) were associated with greater likelihood of treatment with anti-osteoporosis medication.

LIMITATIONS, REASONS FOR CAUTION

Survey data including age of menopause were self-reported by participants; fracture questions were not included in the 2001 survey, and location or level of trauma of self-reported fractures was not asked. Additional risk/protective factors such as vitamin D status, calcium intake, and exercise were not able to be included. Due to sample size, POI and EM were combined for all analyses, and we were unable to differentiate between causes of POI/EM. PBS data were only available from 2004, and hospital admissions data were state-based, with all of Australia were only available from 2007.

WIDER IMPLICATIONS OF THE FINDINGS

This study supports previous literature indicating increased risk of osteoporosis and fractures in women with POI, and adds evidence for women with POI/EM, where there was a relative paucity of data. This is the first study to analyse a variety of clinical and demographic risk factors for osteoporosis and fractures in women with POI/EM, as well as analysing investigation and treatment rates. In these women, using MHT prior to or at study entry, aged 45-50 years, was protective for osteoporosis/fractures; however, having ever used MHT was not, highlighting the importance of early treatment with MHT in these women to preserve bone strength. Although women with POI/EM and osteoporosis or fractures were more likely to use anti-osteoporosis medications than those with usual age menopause, overall treatment rates are low at <40%, demonstrating a significant treatment gap that should be addressed to reduce future fracture risk.

STUDY FUNDING/COMPETING INTEREST(S)

This study was funded by The Australian NHMRC Centre of Research Excellence Women's Health in Reproductive Life (CRE-WHIRL, project number APP1171592). A.R.J. is the recipient of a National Health and Medical Research Council post-graduate research scholarship (grant number 1169192). P.R.E. is supported by a National Health and Medical Research Council grant 1197958. P.R.E. reports grants paid to their institution from Amgen, Sanofi, and Alexion, honoraria from Amgen paid to their institution, and honoraria from Alexion and Kyowa-Kirin.

TRIAL REGISTRATION NUMBER

N/A.

Standardization of in-house anti-IgG and IgA ELISAs for the detection of COVID-19

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the causative agent of coronavirus disease 2019 (COVID-19). RT-PCR detection of viral RNA represents the gold standard method for diagnosis of COVID-19. However, multiple diagnostic tests are needed for acute disease diagnosis and assessing immunity during the COVID-19 outbreak. Here, we developed in-house anti-RBD IgG and IgA enzyme-linked immunosorbent assays (ELISAs) using a well-defined serum sample panel for screening and identification of human SARS-CoV-2 infection. We found that our in-house anti-SARS-CoV-2 IgG ELISA displayed a 93.5% sensitivity and 98.8% specificity whereas our in-house anti-SARS-CoV-2 IgA ELISA provided assay sensitivity and specificity at 89.5% and 99.4%, respectively. The agreement kappa values of our in-house anti-SARS-CoV-2 IgG and IgA ELISA assays were deemed to be excellent and fair, respectively, when compared to RT-PCR and excellent for both assays when compared to Euroimmun anti-SARS-CoV-2 IgG and IgA ELISAs. These data indicate that our in-house anti-SARS-CoV-2 IgG and IgA ELISAs are compatible performing assays for the detection of SARS-CoV-2 infection.

A panel of diverse Klebsiella pneumoniae clinical isolates for research and development

Klebsiella pneumoniae are a leading cause of healthcare-associated infections worldwide. In particular, strains expressing extended-spectrum β-lactamases (ESBLs) and carbapenemases pose serious treatment challenges, leading the World Health Organization (WHO) to designate ESBL and carbapenem-resistant Enterobacteriaceae as 'critical' threats to human health. Research efforts to combat these pathogens can be supported by accessibility to diverse and clinically relevant isolates for testing novel therapeutics. Here, we describe a panel of 100 diverse K. pneumoniae isolates that are publicly available to assist the research community in this endeavour. Whole-genome sequencing (WGS) was performed on 3878 K. pneumoniae clinical isolates housed at the Multidrug-Resistant Organism Repository and Surveillance Network. The isolates were cultured from 63 facilities in 19 countries between 2001 and 2020. Core-genome multilocus sequence typing and high-resolution single-nucleotide polymorphism-based phylogenetic analyses captured the genetic diversity of the collection and were used to select the final panel of 100 isolates. In addition to known multidrug-resistant (MDR) pandemic lineages, the final panel includes hypervirulent lineages and isolates with specific and diverse resistance genes and virulence biomarkers. A broad range of antibiotic susceptibilities, ranging from pan-sensitive to extensively drug-resistant isolates, are described. The panel collection, and all associated metadata and genome sequences, are available at no additional cost and will be an important resource for the research community and for the design and development of novel antimicrobial agents and diagnostics against this important pathogen.

Influenza-Like Symptom Incidence, Illness-Associated Expenses, and Economic Impact Among Healthcare Personnel in Thailand: A Prospective Observational Cohort Study (2020-2021)

OBJECTIVES

We estimated influenza-like symptom (ILS) incidence among healthcare personnel (HCP) in four hospitals and the economic impact due to ILS in the Thai HCP population during July 2020-June 2021 (Thailand's expected 2020 influenza season), which also coincided with the novel coronavirus disease 2019 pandemic.

METHODS

We followed HCP, in a prospective observational cohort, weekly for ≥1 of: muscle pain, cough, runny nose/nasal congestion, sore throat, or difficulty breathing. We fitted population-averaged Poisson regression models to identify factors associated with acquiring ILS and to calculate ILS incidence. We applied epidemiologic parameters to Thailand's HCP population (227 349 persons) to estimate economic impact.

RESULTS

Of 2184 participants, adjusted all-cause ILS incidence was 6.1 episodes per 100 person-years (95% confidence interval 3.4-10.9). Among Thailand's HCP population, 13 909 ILS episodes were estimated to occur annually and would result in US$235 135 economic loss. Controlling for study site and calendar month, factors associated with acquiring ≥1 ILS versus no ILS included being female, having asthma, and using personal protective equipment 'frequently, but not always'.

CONCLUSIONS

All-cause ILS resulted in considerable economic loss among Thai HCP workforce. These findings underscore the importance of public health interventions to reduce the risk of acquiring ILS.

Antibody Responses to the SARS-CoV-2 Ancestral Strain and Omicron Variants in Moderna mRNA-1273 Vaccinated Active-Duty U.S. Navy Sailors and Marines

Omicron and its subvariants have steadily gained greater capability of immune escape compared to other variants of concern, resulting in an increased incidence of reinfections even among vaccinated individuals. We evaluated the antibody response to Omicron BA.1, BA.2, and BA.4/5 in U.S. military members vaccinated with the primary 2-dose series of Moderna mRNA-1273 in a cross-sectional study. While nearly all vaccinated participants had sustained Spike (S) IgG and neutralizing antibodies (ND50) to the ancestral strain, only 7.7% participants had detectable ND50 to Omicron BA.1 at eight months post-vaccination. The neutralizing antibody response to BA.2 and BA.5 was similarly reduced. The reduced antibody neutralization of Omicron correlated with the decreased antibody binding to the Receptor-Binding Domain. The participants' seropositivity to the nuclear protein positively correlated with ND50. Our data emphasizes the need for continuous vigilance in monitoring for emerging variants and the need to identify potential alternative targets for vaccine design.

Simultaneous detection of omicron and other SARS-CoV-2 variants by multiplex PCR MassARRAY technology

The rapid emergence of SARS-CoV-2 variants with high severity and transmutability adds further urgency for rapid and multiplex molecular testing to identify the variants. A nucleotide matrix-assisted laser-desorption-ionization time-of-flight mass spectrophotometry (MALDI-TOF MS)-based assay was developed (called point mutation array, PMA) to identify four major SARS-CoV-2 variants of concern (VOCs) including Alpha, Beta, Delta, and Omicron (namely PMA-ABDO) and differentiate Omicron subvariant (namely PMA-Omicron). PMA-ABDO and PMA-Omicron consist of 24 and 28 mutation sites of the spike gene. Both PMA panels specifically identified VOCs with as low as 10 viral copies/µl. The panel has shown a 100% concordant with the Next Generation Sequencing (NGS) results testing on 256 clinical specimens with real-time PCR cycle threshold (Ct) values less than 26. It showed a higher sensitivity over NGS; 25/28 samples were positive by PMA but not NGS in the clinical samples with PCR Ct higher than 26. Due to the mass of nucleotide used to differentiate between wild-type and mutation strains, the co-infection or recombination of multiple variants can be determined by the PMA method. This method is flexible in adding a new primer set to identify a new emerging mutation site among the current circulating VOCs and the turnaround time is less than 8 h. However, the spike gene sequencing or NGS retains the advantage of detecting newly emerged variants.

Simultaneous Detection of Omicron and Other SARS-CoV-2 Variants by Multiplex PCR MassARRAY Technology

The rapid emergence of SARS-CoV-2 variants with high severity and transmutability adds further urgency for rapid and multiplex molecular testing to identify the variants. A nucleotide matrix-assisted laser-desorption-ionization time-of-flight mass spectrophotometry (MALDI-TOF MS)-based assay was developed (called point mutation array, PMA) to identify four major SARS-CoV-2 variants of concern (VOCs) including Alpha, Beta, Delta, and Omicron (namely PMA-ABDO) and differentiate Omicron subvariant (namely PMA-Omicron). PMA-ABDO and PMA-Omicron consist of 24 and 28 mutation sites of the spike gene. Both PMA panels specifically identified VOCs with as low as 10 viral copies/ µl. The panel has shown a 100% concordant with the Next Generation Sequencing (NGS) results testing on 256 clinical specimens with real-time PCR cycle threshold (Ct) values less than 26. It showed a higher sensitivity over NGS; 25/28 samples were positive by PMA but not NGS in the clinical samples with PCR Ct higher than 26. Due to the mass of nucleotide used to differentiate between wild-type and mutation strains, the co-infection or recombination of multiple variants can be determined by the PMA method. This method is flexible in adding a new primer set to identify a new emerging mutation site among the current circulating VOCs and the turnaround time is less than 8 hours. However, the spike gene sequencing or NGS retains the advantage of detecting newly emerged variants.

Anti-Arbovirus Antibodies Cross-React With Severe Acute Respiratory Syndrome Coronavirus 2

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is found in regions where dengue (DENV) and chikungunya (CHIKV) viruses are endemic. Any serological cross-reactivity between DENV, CHIKV, and SARS-CoV-2 is significant as it could lead to misdiagnosis, increased severity, or cross-protection. This study examined the potential cross-reactivity of anti-DENV and CHIKV antibodies with SARS-CoV-2 using acute and convalescent-phase samples collected before the SARS-CoV-2 pandemic. These included healthy, normal human (NHS, n = 6), CHIKV-positive (n = 14 pairs acute and convalescent), primary DENV-positive (n = 20 pairs), secondary DENV-positive (n = 20 pairs), and other febrile illnesses sera (n = 23 pairs). Samples were tested using an in-house SARS-CoV-2 and a EUROIMMUN IgA and IgG ELISAs. All NHS samples were negative, whereas 3.6% CHIKV, 21.7% primary DENV, 15.7% secondary DENV, and 10.8% febrile diseases sera resulted as anti-SARS-CoV-2 antibody positive. The EUROIMMUN ELISA using spike 1 as the antigen detected more positives among the primary DENV infections than the in-house ELISA using spike 1-receptor binding domain (RBD) protein. Among ELISA-positive samples, four had detectable neutralizing antibodies against SARS-CoV-2 reporter virus particles yet none had detectable neutralizing antibodies against the live Wuhan strain of SARS-CoV-2. These data demonstrated the SARS-CoV-2 diagnostic cross-reactivity, but not neutralizing antibody cross-reactivity, among dengue seropositive cases. IMPORTANCE SARS-CoV-2 continues to cause significant morbidity globally, including in areas where DENV and CHIKV are endemic. Reports using rapid diagnostic and ELISAs have demonstrated that serological cross-reactivity between DENV and SARS-CoV-2 can occur. Furthermore, it has been observed that convalescent DENV patients are at a lower risk of developing COVID-19. This phenomenon can interfere with the accuracy of serological testing and clinical management of both DENV and COVID-19 patients. In this study, the cross-reactivity of primary/secondary anti-DENV, CHIKV, and other febrile illness antibodies with SARS-CoV-2 using two ELISAs has been shown. Among ELISA-positive samples, four had detectable levels of neutralizing antibodies against SARS-CoV-2 reporter virus particles. However, none had detectable neutralizing antibodies against the live Wuhan strain of SARS-CoV-2. These data demonstrated SARS-CoV-2 diagnostic cross-reactivity, but not neutralizing antibody cross-reactivity, among dengue seropositive cases. The data discussed here provide information regarding diagnosis and may help guide appropriate public health interventions.

Homologous or Heterologous COVID-19 Booster Regimens Significantly Impact Sero-Neutralization of SARS-CoV-2 Virus and Its Variants

We determined the levels of neutralizing antibodies against the SARS-CoV-2 ancestral strain, Delta and Omicron variants of concern (VOCs), in 125 healthcare workers who received CoronaVac as their primary vaccination and later received either a single ChAdOx1 or a combi-nation of two consecutive boosters using either two ChAdOx1 doses or a ChAdOx1 or BNT162b2 as the primary and second boosters, respectively, or two doses of BNT162b2. The titers 12 weeks after primary vaccination were inadequate to neutralize all strains. After a single ChAdOx1 booster, the levels of neutralization at Day 30 varied significantly, with only a small proportion of participants developing neutralizing titers against Omicron at Day 7 and 30. The two doses of ChAdOx1 as the booster induced the lowest activity. A combination ChAdOx1 and BNT162b2 induced greater neutralization than by two doses of ChAdOx1. Two doses of BNT162b2 as the booster had the maximal activity against Omicron VOC.

Anti-SARS-CoV-2 IgG antibody levels among Thai healthcare providers receiving homologous and heterologous COVID-19 vaccination regimens

BACKGROUND

We examined SARS-CoV-2 anti-spike 1 IgG antibody levels following COVID-19 vaccination (AstraZeneca [AZ], Sinovac [SV], Pfizer-BioNTech [PZ]) among Thai healthcare providers.

METHODS

Blood specimens were tested using enzyme-linked immunosorbent assay. We analyzed seven vaccination regimens: (1) one dose of AZ or SV, (2) two doses of homologous (2AZ, 2SV) or heterologous (1AZ + 1PZ) vaccines, and (3) three doses of heterologous vaccines (2SV + 1AZ, 2SV + 1PZ). Differences in antibody levels were assessed using Kruskal-Wallis statistic, Mann-Whitney test, or Wilcoxon matched-pairs signed-rank test. Antibody kinetics were predicted using fractional polynomial regression.

RESULTS

The 563 participants had median age of 39 years; 92% were female; 74% reported no underlying medical condition. Antibody levels peaked at 22-23 days in both 1AZ and 2SV vaccinees and dropped below assay's cutoff for positive (35.2 binding antibody units/ml [BAU/ml]) in 55 days among 1AZ vaccinees compared with 117 days among 2SV vaccinees. 1AZ + 1PZ vaccination regimen was highly immunogenic (median 2279 BAU/ml) 1-4 weeks post vaccination. 2SV + 1PZ vaccinees had significantly higher antibody levels than 2SV + 1AZ vaccinees 4 weeks post vaccination (3423 vs. 2105 BAU/ml; p-value < 0.01), and during weeks 5-8 (3656 vs. 1072 BAU/ml; p-value < 0.01). Antibodies peaked at 12-15 days in both 2SV + 1PZ and 2SV + 1AZ vaccinees, but those of 2SV + 1AZ declined more rapidly and dropped below assay's cutoff in 228 days while those of 2SV + 1PZ remained detectable.

CONCLUSIONS

1AZ + 1PZ, 2SV + 1AZ, and 2SV + 1PZ vaccinees had substantial IgG levels, suggesting that these individuals likely mounted sufficient anti-S1 IgG antibodies for possible protection against SARS-CoV-2 infection.

Chimeric Virus-like Particle-Based COVID-19 Vaccine Confers Strong Protection against SARS-CoV-2 Viremia in K18-hACE2 Mice

Virus-like particles (VLPs) are highly immunogenic and versatile subunit vaccines composed of multimeric viral proteins that mimic the whole virus but lack genetic material. Due to the lack of infectivity, VLPs are being developed as safe and effective vaccines against various infectious diseases. In this study, we generated a chimeric VLP-based COVID-19 vaccine stably produced by HEK293T cells. The chimeric VLPs contain the influenza virus A matrix (M1) proteins and the SARS-CoV-2 Wuhan strain spike (S) proteins with a deletion of the polybasic furin cleavage motif and a replacement of the transmembrane and cytoplasmic tail with that of the influenza virus hemagglutinin (HA). These resulting chimeric S-M1 VLPs, displaying S and M1, were observed to be enveloped particles that are heterogeneous in shape and size. The intramuscular vaccination of BALB/c mice in a prime-boost regimen elicited high titers of S-specific IgG and neutralizing antibodies. After immunization and a challenge with SARS-CoV-2 in K18-hACE2 mice, the S-M1 VLP vaccination resulted in a drastic reduction in viremia, as well as a decreased viral load in the lungs and improved survival rates compared to the control mice. Balanced Th1 and Th2 responses of activated S-specific T-cells were observed. Moderate degrees of inflammation and viral RNA in the lungs and brains were observed in the vaccinated group; however, brain lesion scores were less than in the PBS control. Overall, we demonstrate the immunogenicity of a chimeric VLP-based COVID-19 vaccine which confers strong protection against SARS-CoV-2 viremia in mice.

Beneath the surface: Amino acid variation underlying two decades of dengue virus antigenic dynamics in Bangkok, Thailand

Neutralizing antibodies are important correlates of protection against dengue. Yet, determinants of variation in neutralization across strains within the four dengue virus serotypes (DENV1-4) is imperfectly understood. Studies focus on structural DENV proteins, especially the envelope (E), the primary target of anti-DENV antibodies. Although changes in immune recognition (antigenicity) are often attributed to variation in epitope residues, viral processes influencing conformation and epitope accessibility also affect neutralizability, suggesting possible modulating roles of nonstructural proteins. We estimated effects of residue changes in all 10 DENV proteins on antigenic distances between 348 DENV collected from individuals living in Bangkok, Thailand (1994-2014). Antigenic distances were derived from response of each virus to a panel of twenty non-human primate antisera. Across 100 estimations, excluding 10% of virus pairs each time, 77 of 295 positions with residue variability in E consistently conferred antigenic effects; 52 were within ±3 sites of known binding sites of neutralizing human monoclonal antibodies, exceeding expectations from random assignments of effects to sites (p = 0.037). Effects were also identified for 16 sites on the stem/anchor of E which were only recently shown to become exposed under physiological conditions. For all proteins, except nonstructural protein 2A (NS2A), root-mean-squared-error (RMSE) in predicting distances between pairs held out in each estimation did not outperform sequences of equal length derived from all proteins or E, suggesting that antigenic signals present were likely through linkage with E. Adjusted for E, we identified 62/219 sites embedding the excess signals in NS2A. Concatenating these sites to E additionally explained 3.4% to 4.0% of observed variance in antigenic distances compared to E alone (50.5% to 50.8%); RMSE outperformed concatenating E with sites from any protein of the virus (ΔRMSE, 95%IQR: 0.01, 0.05). Our results support examining antigenic determinants beyond the DENV surface.

Dengue viruses, even of the same serotype, are differentially recognized by preexisting antibodies of individuals. With antibody levels being an important indicator of infection risk and pathogenicity, understanding mechanisms underlying these differences are crucial for vaccine design and development. Investigations have primarily targeted surface regions of the envelope protein (E) where virus-antibody interactions were thought to primarily occur. However, the roles of non-surface regions of the E protein as well as nonstructural proteins has been limited. We looked at the entire virus to identify associations between specific changes in the protein sequence and differences in how viruses were recognized by antibodies. In addition to recovering known determinants on the surface, we found signals in other areas on the structural building blocks of the virus. We also identified additional signals on specific areas of a protein that does not form structures of the virus but orchestrate virus formation. Our results point towards broadening the frame of investigation to gain a more comprehensive understanding of mechanisms giving rise to antibody recognition of dengue viruses, and may aid the design and evaluation of vaccines and/or assays to characterize dengue immunity.

A Thermodynamic Model for Interpreting Tryptophan Excitation-Energy-Dependent Fluorescence Spectra Provides Insight Into Protein Conformational Sampling and Stability

It is now over 30 years since Demchenko and Ladokhin first posited the potential of the tryptophan red edge excitation shift (REES) effect to capture information on protein molecular dynamics. While there have been many key efforts in the intervening years, a biophysical thermodynamic model to quantify the relationship between the REES effect and protein flexibility has been lacking. Without such a model the full potential of the REES effect cannot be realized. Here, we present a thermodynamic model of the tryptophan REES effect that captures information on protein conformational flexibility, even with proteins containing multiple tryptophan residues. Our study incorporates exemplars at every scale, from tryptophan in solution, single tryptophan peptides, to multitryptophan proteins, with examples including a structurally disordered peptide, de novo designed enzyme, human regulatory protein, therapeutic monoclonal antibodies in active commercial development, and a mesophilic and hyperthermophilic enzyme. Combined, our model and data suggest a route forward for the experimental measurement of the protein REES effect and point to the potential for integrating biomolecular simulation with experimental data to yield novel insights.

Limited and Short-Lasting Virus Neutralizing Titers Induced by Inactivated SARS-CoV-2 Vaccine

In vitro determination of severe acute respiratory syndrome coronavirus 2 neutralizing antibodies induced in serum samples from recipients of the CoronaVac vaccine showed a short protection period against the original virus strain and limited protection against variants of concern. These data provide support for vaccine boosters, especially variants of concern circulate.

Entomological Risk Assessment for Dengue Virus Transmission during 2016-2020 in Kamphaeng Phet, Thailand

Individual houses with high risks of dengue virus (DENV) transmission might be a source of virus transmission within the neighborhood. We conducted an entomological risk assessment for DENV transmission at the household level, comprising family cohort members residing in the same location, to assess the risk for dengue virus transmitted by mosquito vectors. The studies were conducted in Kamphaeng Phet Province, Thailand, during 2016-2020. Entomological investigations were performed in 35 cohort families on day 1 and day 14 after receiving dengue case reports. DENV was found in 22 Aedes samples (4.9%) out of 451 tested samples. A significantly higher DENV infection rate was detected in vectors collected on day 1 (6.64%) compared to those collected on day 14 (1.82%). Annual vector surveillance was carried out in 732 houses, with 1002 traps catching 3653 Aedes females. The majority of the 13,228 water containers examined were made from plastic and clay, with used tires serving as a primary container, with 59.55% larval abundance. Larval indices, as indicators of dengue epidemics and to evaluate disease and vector control approaches, were calculated. As a result, high values of larval indices indicated the considerably high risk of dengue transmission in these communities.

Correlation between reported dengue illness history and seropositivity in rural Thailand

In the latest World Health Organization (WHO) recommendation for Dengvaxia implementation, either serological testing or a person's history of prior dengue illness may be used as supporting evidence to identify dengue virus (DENV)-immune individuals eligible for vaccination, in areas with limited capacity for laboratory confirmation. This analysis aimed to estimate the concordance between self-reported dengue illness histories and seropositivity in a prospective cohort study for dengue virus infection in Kamphaeng Phet province, a dengue-endemic area in northern Thailand. The study enrolled 2,076 subjects from 516 multigenerational families, with a median age of 30.6 years (range 0-90 years). Individual and family member dengue illness histories were obtained by questionnaire. Seropositivity was defined based on hemagglutination inhibition (HAI) assays. Overall seropositivity for DENV was 86.5% among those aged 9-45 years, which increased with age. 18.5% of participants reported a history of dengue illness prior to enrollment; 30.1% reported a previous DENV infection in the family, and 40.1% reported DENV infection in either themselves or a family member. Relative to seropositivity by HAI in the vaccine candidate group, the sensitivity and specificity of individual prior dengue illness history were 18.5% and 81.6%, respectively; sensitivity and specificity of reported dengue illness in a family member were 29.8% and 68.0%, and of either the individual or a family member were 40.1% and 60.5%. Notably, 13.4% of individuals reporting prior dengue illness were seronegative. Given the high occurrence of asymptomatic and mild DENV infection, self-reported dengue illness history is poorly sensitive for prior exposure and may misclassify individuals as 'exposed' when they were not. This analysis highlights that a simple, highly sensitive, and highly specific test for determining serostatus prior to Dengvaxia vaccination is urgently needed.

Comparative Analyses of Historical Trends in Confirmed Dengue Illnesses Detected at Public Hospitals in Bangkok and Northern Thailand, 2002-2018

Dengue is a re-emerging global public health problem, the most common arbovirus causing human disease in the world, and a major cause of hospitalization in endemic countries causing significant economic burden. Data were analyzed from passive surveillance of hospital-attended dengue cases from 2002 to 2018 at Phramongkutklao Hospital (PMKH) located in Bangkok, Thailand, and Kamphaeng Phet Provincial Hospital (KPPH) located in the lower northern region of Thailand. At PMKH, serotype 1 proved to be the most common strain of the virus, whereas at KPPH, serotypes 1, 2, and 3 were the most common strains from 2006 to 2008, 2009 to 2012, and 2013 to 2015, respectively. The 11–17 years age-group made up the largest proportion of patients impacted by dengue illnesses during the study period at both sites. At KPPH, dengue virus (DENV)-3 was responsible for most cases of dengue fever (DF), whereas it was DENV-1 at PMKH. In cases where dengue hemorrhagic fever was the clinical diagnosis, DENV-2 was the predominant serotype at KPPH, whereas at PMKH, it was DENV-1. The overall disease prevalence remained consistent across the two study sites with DF being the predominant clinical diagnosis as the result of an acute secondary dengue infection, representing 40.7% of overall cases at KPPH and 56.8% at PMKH. The differences seen between these sites could be a result of climate change increasing the length of dengue season and shifts in migration patterns of these populations from rural to urban areas and vice versa.

Genomic surveillance of SARS-CoV-2 in Thailand reveals mixed imported populations, a local lineage expansion and a virus with truncated ORF7a

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There were multiple introduction events of SARS-CoV-2 into Thailand.

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One lineage, designated A/Thai-1, has expanded and has become a predominant and unique lineage in Thailand.

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A major frame-shift mutation was found at the gene encoding ORF7a, a putative host antagonizing factor of the virus.

Coronavirus Disease 2019 (COVID-19) is a global public health threat. Genomic surveillance of SARS-CoV-2 was implemented in March of 2020 at a major diagnostic hub in Bangkok, Thailand. Several virus lineages supposedly originated in many countries were found, and a Thai-specific lineage, designated A/Thai-1, has expanded to be predominant in Thailand. A virus sample in the SARS-CoV-2 A/Thai-1 lineage contains a frame-shift deletion at ORF7a, encoding a putative host antagonizing factor of the virus.

Development of the MapMe intervention body image scales of known weight status for 4-5 and 10-11 year old children

Background

Parents tend to visually assess children to determine their weight status and typically underestimate child body size. A visual tool may aid parents to more accurately assess child weight status and so support strategies to reduce childhood overweight. Body image scales (BIS) are visual images of people ranging from underweight to overweight but none exist for children based on UK criteria. Our aim was to develop sex- and age-specific BIS for children, based on British growth reference (UK90) criteria.

Methods

BIS were developed using 3D surface body scans of children, their associated weight status using UK90 criteria from height and weight measurements, and qualitative work with parents and health professionals.

Results

Height, weight and 3D body scans were collected (211: 4–5 years; 177: 10–11 years). Overall, 12 qualitative sessions were held with 37 participants. Four BIS (4–5-year-old girls and boys, 10–11-year-old girls and boys) were developed.

Conclusions

This study has created the first sex- and age-specific BIS, based on UK90 criteria. The BIS have potential for use in child overweight prevention and management strategies, and in future research. This study also provides a protocol for the development of further BIS appropriate to other age groups and ethnicities.

DNAscan: personal computer compatible NGS analysis, annotation and visualisation

BACKGROUND

Next Generation Sequencing (NGS) is a commonly used technology for studying the genetic basis of biological processes and it underpins the aspirations of precision medicine. However, there are significant challenges when dealing with NGS data. Firstly, a huge number of bioinformatics tools for a wide range of uses exist, therefore it is challenging to design an analysis pipeline. Secondly, NGS analysis is computationally intensive, requiring expensive infrastructure, and many medical and research centres do not have adequate high performance computing facilities and cloud computing is not always an option due to privacy and ownership issues. Finally, the interpretation of the results is not trivial and most available pipelines lack the utilities to favour this crucial step.

RESULTS

We have therefore developed a fast and efficient bioinformatics pipeline that allows for the analysis of DNA sequencing data, while requiring little computational effort and memory usage. DNAscan can analyse a whole exome sequencing sample in 1 h and a 40x whole genome sequencing sample in 13 h, on a midrange computer. The pipeline can look for single nucleotide variants, small indels, structural variants, repeat expansions and viral genetic material (or any other organism). Its results are annotated using a customisable variety of databases and are available for an on-the-fly visualisation with a local deployment of the gene.iobio platform. DNAscan is implemented in Python. Its code and documentation are available on GitHub: https://github.com/KHP-Informatics/DNAscan . Instructions for an easy and fast deployment with Docker and Singularity are also provided on GitHub.

CONCLUSIONS

DNAscan is an extremely fast and computationally efficient pipeline for analysis, visualization and interpretation of NGS data. It is designed to provide a powerful and easy-to-use tool for applications in biomedical research and diagnostic medicine, at minimal computational cost. Its comprehensive approach will maximise the potential audience of users, bringing such analyses within the reach of non-specialist laboratories, and those from centres with limited funding available.

A remotely triggered fast neutron detection instrument based on a plastic organic scintillator

A detector system for the characterization of radiation fields of both fast neutrons and γ rays is described comprising of a gated photomultiplier tube (PMT), an EJ299-33 solid organic scintillator detector, and an external trigger circuit. The objective of this development was to conceive a means by which the PMT in such a system can be actuated remotely during the high-intensity bursts of pulsed γ-ray contamination that can arise during active interrogation procedures. The system is used to detect neutrons and γ rays using established pulse-shape discrimination (PSD) techniques. The gating circuit enables the PMT to be switched off remotely. This is compatible with use during intense radiation transients to avoid saturation and the disruption of the operation of the PMT during the burst. Data are presented in the form of pulse-height spectra and PSD scatter plots for the system triggered with a strobed light source. These confirm that the gain of the system and the throughput for both triggered and un-triggered scenarios are as expected, given the duty cycle of the stimulating radiation. This demonstrates that the triggering function does not perturb the system response of the detector.

Mothers' perceptions of child weight status and the subsequent weight gain of their children: a population-based longitudinal study

BACKGROUND

There is a plethora of cross-sectional work on maternal perceptions of child weight status showing that mothers typically do not classify their overweight child as being overweight according to commonly used clinical criteria. Awareness of overweight in their child is regarded as an important prerequisite for mothers to initiate appropriate action. The gap in the literature is determining whether, if mothers do classify their overweight child's weight status correctly, this is associated with a positive outcome for the child's body mass index (BMI) at a later stage.

OBJECTIVE

To explore longitudinal perceptions of child weight status from mothers of a contemporary population-based birth cohort (Gateshead Millennium Study) and relationships of these perceptions with future child weight gain.

METHODS

Data collected in the same cohort at 7, 12 and 15 years of age: mothers' responses to two items concerning their child's body size; child's and mother's BMI; pubertal maturation; demographic information.

RESULTS

Mothers' perceptions of whether their child was overweight did not change markedly over time. Child BMI was the only significant predictor of mothers' classification of overweight status, and it was only at the extreme end of the overweight range and in the obese range that mothers reliably described their child as overweight. Even when mothers did appropriately classify their child as overweight at an earlier stage, this was not related to relatively lower child BMI a few years later.

CONCLUSIONS

Mothers tend to classify their child as overweight in only more extreme cases. It is an important finding that no beneficial impact was shown on later child BMI in overweight children whose mothers classified their child's weight status as overweight at an earlier stage.

Review: Placental adaptations to the presence of maternal asthma during pregnancy

Asthma is a highly prevalent chronic medical condition affecting an estimated 12% of pregnant, women each year, with prevalence of asthma greatest (up to 16%) among the socially disadvantaged. Maternal asthma is associated with significant perinatal morbidity and mortality including preterm births, neonatal hospitalisations and low birthweight outcomes each year. We have identified that the placenta adapts to the presence of chronic, maternal asthma during pregnancy in a sex specific manner that may confer sex differences in fetal outcome. The male fetus was at greater risk of a poor outcome than a female fetus in the presence of maternal asthma and an acute inflammatory event such as an asthma exacerbation. This review will examine the role of sex specific differences in placental function on fetal growth and survival.

Transition from paediatric surgery: how many patients do we need to plan for?

INTRODUCTION Transitional care is an NHS priority with newly published NICE guidance. Many paediatric surgical patients need quality care to continue into adulthood. We undertook an evaluation of our departmental activity to assess the magnitude of this issue. METHODS We identified all outpatients ≥ 15 years (potentially requiring imminent transition) seen over a 12 month period for all five general paediatric surgery consultants in our tertiary centre. Those patients requiring transition were highlighted and the appropriate adult team for referral recorded. RESULTS There were 2989 general paediatric surgery clinic appointments within the year; 289 (9.7%) were for young people aged 15 years or older; 62 patients (28% of those ≥ 15years) were deemed to require transition into adult care. Significantly more patients having colorectal surgery required follow-up (P = 0.0009 Chi-square test) compared with patients in other subspecialties. CONCLUSIONS More patients than expected required transition. This may be the case in other units. Current best practice includes time intensive preclinic planning, careful preparation of patient and family, followed by joint clinics. A joint clinic appointment takes 30 minutes, allowing for comprehensive handover and forging new relationships. In our department, we need at least ten transition clinics across 2 years. Coalition with adult colleagues is vital. These data enable us to plan services to provide quality care for our adolescent patients and highlights colorectal surgery as a priority.

An assessment of the doses received by members of the public in Japan following the nuclear accident at Fukushima Daiichi nuclear power plant

The earthquake and tsunami on 11 March 2011, centred off the east coast of Japan, caused considerable destruction and substantial loss of life along large swathes of the Japanese coastline. The tsunami damaged the Fukushima Daiichi nuclear power plant (NPP), resulting in prolonged releases of radioactive material into the environment. This paper assesses the doses received by members of the public in Japan. The assessment is based on an estimated source term and atmospheric dispersion modelling rather than monitoring data. It is evident from this assessment that across the majority of Japan the estimates of dose are very low, for example they are estimated to be less than the annual average dose from natural background radiation in Japan. Even in the regions local to Fukushima Daiichi NPP (and not affected by any form of evacuation) the maximum lifetime effective dose is estimated to be well below the cumulative natural background dose over the same period. The impact of the urgent countermeasures on the estimates of dose was considered. And the relative contribution to dose from the range of exposure pathways and radionuclides were evaluated. Analysis of estimated doses focused on the geographic irregularity and the impact of the meteorological conditions. For example the dose to an infant's thyroid received over the first year was estimated to be greater in Hirono than in the non-evacuated region of Naraha, despite Hirono being further from the release location. A number of factors were identified and thought to contribute towards this outcome, including the local wind pattern which resulted in the recirculation of part of the release. The non-uniform nature of dose estimates strengthens the case for evaluations based on dispersion modelling.

Altered gene expression in the dorsolateral prefrontal cortex of individuals with schizophrenia

The underlying pathology of schizophrenia (SZ) is likely as heterogeneous as its symptomatology. A variety of cortical and subcortical regions, including the prefrontal cortex, have been implicated in its pathology, and a number of genes have been identified as risk factors for disease development. We used in situ hybridization (ISH) to examine the expression of 58 genes in the dorsolateral prefrontal cortex (DLPFC, comprised of Brodmann areas 9 and 46) from 19 individuals with a premorbid diagnosis of SZ and 33 control individuals. Genes were selected based on: (1) previous identification as risk factors for SZ; (2) cell type markers or (3) laminar markers. Cell density and staining intensity were compared in the DLPFC, as well as separately in Brodmann areas 9 and 46. The expression patterns of a variety of genes, many of which are associated with the GABAergic system, were altered in SZ when compared with controls. Additional genes, including C8orf79 and NR4A2, showed alterations in cell density or staining intensity between the groups, highlighting the need for additional studies. Alterations were, with only a few exceptions, limited to Brodmann area 9, suggesting regional specificity of pathology in the DLPFC. Our results agree with previous studies on the GABAergic involvement in SZ, and suggest that areas 9 and 46 may be differentially affected in the disease. This study also highlights additional genes that may be altered in SZ, and indicates that these potentially interesting genes can be identified by ISH and high-throughput image analysis techniques.

Mothers' judgements about their child's weight: distinguishing facts from values

BACKGROUND

Mothers' responses to questionnaire items assessing their child's weight status typically do not correspond to conventional clinical classifications based on body mass index (BMI). From this observation health professionals infer that mothers do not recognize overweight in their child. But the questions used have generally confounded factual judgements with values, so it is not clear whether the mothers are making factual errors, or differ from professionals in their values.

METHODS

Cross-sectional study of population-based birth cohort at 6-8 years and their mothers (n = 540). An objective BMI matching task was used to determine the accuracy of mothers' recognition of their child's weight. Mothers matched their child to sex- and age-specific images of children of known BMI ranging from very thin to obese, and chose a descriptor of their child's weight of the kind used in previous research.

RESULTS

Mothers tended to underestimate their child's BMI on the matching task. Matching errors significantly predicted mothers' description of their child's weight; those who overestimated their child's BMI on the matching task were more likely to say their child was overweight, while those who underestimated it were less likely to, independently of their child's actual BMI.

CONCLUSIONS

Educational programmes aimed at parents of young primary school children need to address separately the factual and the evaluative components of their assessment of child weight.

16(th) IHIW: extending the number of resources and bioinformatics analysis for the investigation of HLA rare alleles

Continuing a project presented at the 15th International HLA and Immunogenetics Workshop (IHIWS) on the rarity of HLA alleles, we sought to expand the number of data sources and bioinformatics tools available in the Allele Frequencies Net Database website (AFND, www.allelefrequencies.net). In this 16th IHIWS Rare Alleles project, HLA alleles described in the latest IMGT/HLA Database (release 3.8.0) were queried against different sources including data from registries (stem cell) and from 74 different laboratories around the world. We demonstrated that approximately 40% of the alleles officially named in the IMGT/HLA Database have been reported only once across all different sources. To facilitate the large-scale analysis of rare alleles, we have produced an online tool called the Rare Allele Detector that simplifies the detection of alleles that are considered to be 'very rare', 'rare' or 'frequent'. Tools and associated data can be accessed via the www.allelefrequencies.net website.

When do mothers think their child is overweight?

OBJECTIVE

To quantify how overweight children have to be for their mothers to classify them as overweight and to express concern about future overweight, and to investigate the adiposity cues in children that mothers respond to.

DESIGN

Cross-sectional.

SUBJECTS

A total of 531 children from the Gateshead Millennium Study cohort at 6-8 years and their mothers.

MEASUREMENTS

In the mother: responses to two questions concerning the child's adiposity; height; weight; educational qualifications; and economic status. In the child: height; weight; waist circumference; skinfold thicknesses; bioelectrical impedance; and bone frame measurements.

RESULTS

The body mass index (BMI) at which half the mothers classify their child as overweight was 21.3 (in the obese range for children of this age). The BMI at which half the mothers were concerned about their child becoming overweight in the future was 17.1 (below the overweight range). Waist circumference and skinfolds contributed most to mothers' responses. Although BMI and fat scores were important predictors individually, they did not contribute independently once waist circumference and skinfolds (their most visible manifestations) were included in the regression equations. Mothers were less likely to classify girls as overweight. Mothers with higher BMIs were less likely to classify their child as overweight, but were more likely to be concerned about future overweight.

CONCLUSION

Health promotion efforts directed at parents of young primary school children might better capitalise on their concern about future overweight in their child than on current weight status, and focus on mothers' response to more visible characteristics than the BMI.

Effect of annealing temperatures on the secondary re-crystallization of extruded PM2000 steel bar

The ferritic oxide dispersion-strengthened alloy PM2000 is an ideal candidate for high-temperature applications as it contains uniform nano-oxide dispersoids, which act as pinning points to obstruct dislocation and grain boundary motion and therefore impart excellent creep resistance. The development of the microstructure during re-crystallization of oxide dispersion-strengthened alloys has been discussed by a number of authors, but the precise mechanism of secondary re-crystallization still remains uncertain. Hence, this work is aimed at investigating the re-crystallization behaviour of extruded PM2000 bar for different annealing temperatures, using electron backscatter diffraction, in particular, to determine grain orientations, grain boundary misorientation angles, etc. The results show that the as-extruded bar microstructure comprises both low-angle grain boundaries pinned by oxide particles and high-angle boundaries that will have inherent boundary mobility to allow boundary migration. In addition, dynamical re-crystallization was found in the outer region of the non-heat-treated PM2000 bar, which suggested that deformation heterogeneities can be introduced during thermo-mechanical processing that enhance the nucleation of re-crystallization. Subsequent heat treatments promote and stimulate secondary re-crystallization, giving rise to large grains with few sub-grain boundaries.

Initial treatment with fixed-dose combination rosiglitazone/glimepiride in patients with previously untreated type 2 diabetes

AIM

This study assessed the efficacy and safety of two different dosing regimens of fixed-dose combination (FDC) rosiglitazone (RSG) plus glimepiride (GLIM) compared with RSG or GLIM monotherapy in drug-naive subjects with type 2 diabetes mellitus (T2DM).

METHODS

Drug-naive subjects (n = 901) were enrolled into this 28-week, double-blind, parallel-group study if their glycosylated haemoglobin A(1c) (HbA(1c)) was >7.5% but <or=12%. Subjects were randomized to receive either GLIM [4 mg once daily (OD) maximal], RSG (8 mg OD maximal) or RSG/GLIM FDC regimen A (4 mg/4 mg OD maximal) or RSG/GLIM FDC regimen B (8 mg/4 mg OD maximal). Patients were assessed for efficacy and safety every 4 weeks for the first 12 weeks of the study, and at weeks 20 and 28. The primary efficacy endpoint was change in HbA(1c) from baseline. Key secondary endpoints included the proportion of patients achieving recommended HbA(1c) and fasting plasma glucose (FPG) targets; change from baseline in FPG, insulin, C-reactive protein (CRP), adiponectin, free fatty acids and lipids; and percentage change in homeostasis model assessment-estimated insulin sensitivity and beta-cell function. Safety evaluations included adverse-event (AE) monitoring and clinical laboratory evaluations.

RESULTS

At week 28, both RSG/GLIM FDC regimens significantly reduced HbA(1c) (mean +/- s.d.: -2.4 +/- 1.4% FDC regimen A; -2.5 +/- 1.4% FDC regimen B) to a greater extent than RSG (-1.8 +/- 1.5%) or GLIM (-1.7 +/- 1.4%) monotherapy (model-adjusted mean treatment difference, p < 0.0001 vs. both RSG and GLIM). Significantly more subjects achieved HbA(1c) target levels of <or=6.5 and <7% with either RSG/GLIM FDC regimen compared with RSG or GLIM alone (model-adjusted odds ratio, p < 0.0001 for both comparisons). Similarly, a significantly greater reduction in FPG levels was observed in subjects treated with the RSG/GLIM FDC [mean +/- s.d. (mg/dl): -69.5 +/- 57.5 FDC regimen A; -79.9 +/- 56.8 FDC regimen B) compared with RSG (-56.6 +/- 58.1) or GLIM (-42.2 +/- 66.1) monotherapy (model-adjusted mean treatment difference, p < 0.0001 for both comparisons). Improvement in CRP was also observed in subjects who were treated with a RSG/GLIM FDC or RSG monotherapy compared with GLIM monotherapy. RSG/GLIM FDC was generally well tolerated, with no new safety or tolerability issues identified from its monotherapy components, and a similar AE profile was observed across FDC regimens. The most commonly reported AE was hypoglycaemia, and the incidence of confirmed symptomatic hypoglycaemia (3.6-5.5%) was comparable among subjects treated with an RSG/GLIM FDC and GLIM monotherapy.

CONCLUSIONS

Compared with RSG or GLIM monotherapy, the RSG/GLIM FDC improved glycaemic control with no significant increased risk of hypoglycaemia. RSG/GLIM FDC provides an effective and well-tolerated treatment option for drug-naive individuals with T2DM.

Protocol for evaluation of automated blood cell counters. International Committee for Standardization in Haematology (ICSH)

This protocol is proposed for the evaluation of automated blood cell counters to assess the performance, advantages and limitations of such instruments. It is based on the International Committee for Standardization in Haematology (ICSH) 'Protocol for type testing equipment and apparatus used for haematological analysis' (1978a) and the British Committee for Standardization in Haematology 'Guidelines for the evaluation of instruments used in haematology' (Shinton, England & Kennedy, 1982). The document has been prepared by the ICSH Panel on Cytometry after discussion with colleagues. This tentative protocol will be reviewed 1 year after publication, in accordance with the ICSH rules, before it is adopted as a definitive standard.

Control of glycolysis in mature boar spermatozoa: effect of pH in vitro

The glycolytic pathway in boar sperm is sensitive to pH, which decreases as lactate is produced from either glucose or fructose in vitro. The build up of lactate appears to be due to the saturation of mitochondrial lactate transporters, which causes the cytoplasmic pH to fall. Phosphofructokinase has been shown to be sensitive to this drop in pH rather than to the build up of lactate ions or ATP, thereby controlling the rate of glycolysis in vitro.

Whole-grain intake of British young people aged 4–18 years

Inverse associations between whole-grain food consumption and risk of CVD, some cancers and type 2 diabetes have been reported. However, there are few reports of whole-grain intake, particularly among young people. The objective of the present study was to estimate whole-grain intake in a nationally representative sample of young people aged 4–18 years living in Great Britain. Whole-grain intake was estimated using 7d weighed dietary records from 1583 young people who participated in the cross-sectional National Diet and Nutrition Survey in 1997. Whole-grain intake was quantified from the consumption of all foods containing ≥10% whole-grain content. Median whole-grain intake was 7g/d (interquartile range 0–19g/d), with a corresponding mean of 13 (sd18) g/d. Intake was significantly lower among young people whose head of household had a manual occupation, but did not differ significantly by sex, age, region or season. There was no whole-grain intake for 27% of participants. The percentages for less than one and less than three 16g amounts of whole-grain intake per d were 70 and 94, respectively, while corresponding percentages based on 20g amounts were 76 and 97. Foods with <51% whole-grain content provided 28% of whole-grain intake overall, with a higher percentage in older adolescents. The main sources of whole-grain intake were breakfast cereals (56%) and bread (25%). The present study provides the first quantification of absolute whole-grain intake from all significant food sources in any representative age group in the UK. Although there is some debate regarding the quantity of whole grains required for good health, whole-grain intake among British young people is low.

Radioactive materials in biosolids: dose modeling

The Interagency Steering Committee on Radiation Standards (ISCORS) has recently completed a study of the occurrence within the United States of radioactive materials in sewage sludge and sewage incineration ash. One component of that effort was an examination of the possible transport of radioactivity from sludge into the local environment and the subsequent exposure of humans. A stochastic environmental pathway model was applied separately to seven hypothetical, generic sludge-release scenarios, leading to the creation of seven tables of Dose-to-Source Ratios (DSR), which can be used in translating from specific activity in sludge into dose to an individual. These DSR values were then combined with the results of an ISCORS survey of sludge and ash at more than 300 publicly owned treatment works, to explore the potential for radiation exposure of sludge workers and members of the public. This paper provides a brief overview of the pathway modeling methodology employed in the exposure and dose assessments and discusses technical aspects of the results obtained.

Lack of antifertility properties of novel halogenated glycolytic inhibitors and the urinary excretion and metabolism of 1,6-dichloro-1,6-dideoxy-D-fructofuranose in the male rat

The antifertility action of (R,S)-alpha-chlorohydrin administered orally to male rats was compared with that of several novel chlorinated compounds known to inhibit glycolysis and the kinematics of rat sperm in vitro. Oral gavage of 1,6-dichloro-1,6-dideoxy-D-fructofuranose (dichlorodideoxyfructose, DCF), 1-chloro-3-hydroxypropanone, its dimethylketal and bromopyruvate did not reduce the fertility of male rats below that of controls at the equivalent antifertility dose of (R,S)-alpha-chlorohydrin (5 mg/kg/day) or higher. As anticipated for a compound cleaved to products of (S)-chirality even high doses of DCF (200 mg/kg) showed no effect on renal function. 36Cl-Labelled DCF administered orally to male rats was eliminated only slowly in the urine (16% of the ingested dose excreted in 96 h). In the first 8 h, approximately 50% of DCF was excreted unchanged, 30% was excreted as 3-chlorolactate (BCLA), the oxidation product 3-chlorolactaldehyde and 25% as Cl-. By 24 h little DCF remained and the major metabolite (70%) was BCLA and 20% Cl-. The high rate of dechlorination is most likely responsible for the low antifertility action of DCF.

MRI susceptibility artefacts related to scaphoid screws: the effect of screw type, screw orientation and imaging parameters

Metal implants produce susceptibility artefacts in magnetic resonance imaging. We have explored the effects of scaphoid screw characteristics and orientation on MR susceptibility artefact. Titanium alloy, smallness and longitudinal alignment with the z-axis of the main magnetic field reduce the size of the susceptibility artefact.

The effect of (R,S)-ornidazole on the fertility of male mice and the excretion and metabolism of 36Cl-(R,S)-ornidazole and 36Cl-(R,S)-alpha-chlorohydrin in male mice and rats

(R,S)-Ornidazole, an effective antifertility agent for male rats at 400 mg/kg/day, was ineffective at this dose in male mice and at 1000 mg/kg/day caused neural effects. The compound was not excreted unchanged and more polar metabolites and Cl- were detected in 0-8 h urine following a single injection (400 mg/kg). In 8-24 h urine even these metabolites and most Cl ion were absent, indicating rapid metabolism of ornidazole. There was no organ specific accumulation of 36Cl-(R,S)-ornidazole in murine tissues. After injection of 36Cl-(R,S)-alpha-chlorohydrin, another antifertility agent in the rat but not the mouse, there was also no tissue-specific accumulation of radioactivity in the reproductive tract of either species. Urinary excretion rates of alpha-chlorohydrin were twice as rapid in mice as in rats. In mice, alpha-chlorohydrin was the major urinary metabolite, but in the rat metabolites included Cl-, 3-chlorolactate (BCLA) at 5 and 10 h and BCLA only at 24 h. BCLA was the major metabolite detected in most tissues at 10 and 24 h. In the rat cauda (but not caput) epididymidis the glycolytic inhibitor 3-chlorolactaldehyde was present at 5 h (but not 10 h), indicative of early metabolism. These results demonstrate a greater metabolism and excretion of putative antifertility agents in the mouse than the rat, lowering the amount of effective inhibitor circulating in the animal, which may explain why (R,S)-alpha-chlorohydrin and (R,S)-ornidazole are ineffective in this species at the dosages and injection times used, despite their spermatozoa being sensitive to inhibition by (R,S)-alpha-chlorohydrin in vitro.

Fructose metabolism by mature boar spermatozoa

In 1945, Mann showed fructose to be the principal sugar in semen. For over half a century the means by which fructose is metabolized by sperm has been assumed to be by an initial phosphorylation catalysed by hexokinase, but this has never been substantiated. In the present study, by comparing the metabolism of glucose and fructose by both whole boar sperm and hypotonically treated cells, it is confirmed that fructose is phosphorylated by hexokinase to produce fructose 6-phosphate.

Smoke alarm ownership and installation: a comparison of a rural and a suburban community in Georgia

As part of a smoke alarm giveaway and installation program (The Get-Alarmed Campaign), a total of 454 households were surveyed in two counties in Georgia, one metropolitan and one nonmetropolitan. The targeted communities in these counties had a high prevalence of low-income and minority populations and thus were at high risk of house fire-related morbidity and mortality. The objectives of the program were to determine the prevalence of and predictors for installed, functioning smoke alarms, and to install at least one smoke alarm and/or smoke alarm batteries in 100% of participating homes in need. Characteristics associated with smoke alarm ownership included home ownership, having a higher income, and having a central heating source, factors which should be considered in targeting future intervention strategies. At onset, 159/454 households (35.0%) had no smoke alarms installed and 56/275 households with existing smoke alarms (20.4%) had none that were functional. Regardless of ownership status, a free smoke alarm was installed in the household of 93.8% of participants and new batteries were installed in existing smoke alarms for 31.7% of participants. This project illustrates the usefulness of a door-to-door campaign in increasing smoke alarm ownership in both a rural and a suburban community with a high concentration of residents at high risk of house fire-related morbidity and mortality.

MRI assessment of the proximal pole of the scaphoid after internal fixation with a titanium alloy Herbert screw

We report a series of scaphoid fractures fixed with titanium alloy Herbert screws in which postoperative Magnetic Resonance Imaging (MRI) was used to assess the marrow signal in the proximal pole of the scaphoid and thus detect the presence of avascular necrosis. The artefact produced by the titanium alloy Herbert screw did not preclude this assessment.

Root mucilage from pea and its utilization by rhizosphere bacteria as a sole carbon source

Plant roots secrete a complex polysaccharide mucilage that may provide a significant source of carbon for microbes that colonize the rhizosphere. High molecular weight mucilage was separated by high-pressure liquid chromatography gel filtration from low molecular weight components of pea root exudate. Purified pea root mucilage generally was similar in sugar and glycosidic linkage composition to mucilage from cowpea, wheat, rice, and maize, but appeared to contain an unusually high amount of material that was similar to arabinogalactan protein. Purified pea mucilage was used as the sole carbon source for growth of several pea rhizosphere bacteria, including Rhizobium leguminosarum 8401 and 4292, Burkholderia cepacia AMMD, and Pseudomonas fluorescens PRA25. These species grew on mucilage to cell densities of three- to 25-fold higher than controls with no added carbon source, with cell densities of 1 to 15% of those obtained on an equal weight of glucose. Micromolar concentrations of nod gene-inducing flavonoids specifically stimulated mucilage-dependent growth of R. leguminosarum 8401 to levels almost equaling the glucose controls. R. leguminosarum 8401 was able to hydrolyze p-nitrophenyl glycosides of various sugars and partially utilize a number of purified plant polysaccharides as sole carbon sources, indicating that R. leguminosarum 8401 can make an unexpected variety of carbohydrases, in accordance with its ability to extensively utilize pea root mucilage.

Susceptibility of glycolytic enzyme activity and motility of spermatozoa from rat, mouse, and human to inhibition by proven and putative chlorinated antifertility compounds in vitro

Nonhormonal contraceptives that act by blocking energy metabolism within sperm have the advantage over spermatogenic inhibitors by their fast onset of infertility and their almost immediate restoration of fertility after withdrawal of the contraceptive agent. This study was done to test new chlorinated compounds for their contraceptive potency on rodent and human sperm in vitro. Cells were incubated in a medium containing glucose as the sole energy source with 1-chloro-3-hydroxypropanone (CHOP) and 1,6-dichloro-1,6-dideoxy-D-fructose (DCDF), chlorinated analogues of glycolytic substrates, as well as racemic (R,S)-alpha-chlorohydrin (ACH). After incubation, enzymatic activity and kinematic parameters were estimated. A dose-dependent inhibition of the glycolytic enzyme, glyceraldehyde 3-phosphate dehydrogenase (GAPDH), of rat and mouse distal cauda epididymidal and human ejaculated sperm by ACH, CHOP, and DCDF was demonstrated. Triosephosphate isomerase (TPI) was inhibited by ACH, but not by CHOP and DCDF, irrespective of species. All compounds inhibited sperm motility and kinematic parameters with increasing concentration. The results confirm that inhibition of glycolytic enzymes of sperm, including those of human, can be effectively brought about by a variety of chloro-compounds that can be converted to (S)-3-chlorolactaldehyde, the stereospecific chloro-derivative of the enzyme's natural substrate, (R)-glyceraldehyde 3-phosphate, and could be developed into contraceptive agents for men.

Expression profiling using microarrays fabricated by an ink-jet oligonucleotide synthesizer

We describe a flexible system for gene expression profiling using arrays of tens of thousands of oligonucleotides synthesized in situ by an ink-jet printing method employing standard phosphoramidite chemistry. We have characterized the dependence of hybridization specificity and sensitivity on parameters including oligonucleotide length, hybridization stringency, sequence identity, sample abundance, and sample preparation method. We find that 60-mer oligonucleotides reliably detect transcript ratios at one copy per cell in complex biological samples, and that ink-jet arrays are compatible with several different sample amplification and labeling techniques. Furthermore, results using only a single carefully selected oligonucleotide per gene correlate closely with those obtained using complementary DNA (cDNA) arrays. Most of the genes for which measurements differ are members of gene families that can only be distinguished by oligonucleotides. Because different oligonucleotide sequences can be specified for each array, we anticipate that ink-jet oligonucleotide array technology will be useful in a wide variety of DNA microarray applications.

Glycolytic enzyme activity in hypotonically treated boar spermatozoa

Treatment of washed boar sperm with hypotonic phosphate buffer disrupted the cytoplasmic membrane and released the soluble contents and phosphofructokinase, but the other glycolytic enzymes and lactate dehydrogenase were retained. Addition of the appropriate substrates and co-factor(s) to preparations of treated cells in phosphate-buffered saline showed that enzyme activity could be re-instated. This simple preparation should be of assistance in the investigation of specific sections of the glycolytic pathway without the use of chemical inhibitors.

Influence of a rural primary care clerkship on medical students' intentions to practice in a rural community

The purpose of this study is to examine the relationship of a rural clerkship to medical students' interest in establishing careers in rural communities. The Association of American Medical Colleges Medical School Graduation Questionnaire (GQ) for years 1988 through 1997 was examined to compare the career plans of students graduating from Morehouse School of Medicine (MSM) with those of all students graduating from United States medical schools before the period 1988 through 1992 and after the period 1993 through 1997, after the inception of the rural clerkship at MSM. Select GQ data items examined include student demographics, medical school experiences, and career plans. Statistical analyses were used to compare pre- and post-clerkship responses for MSM students and to compare their responses with the national trends. Results indicate that, following a transition period, MSM students showed an increased preference for a future career in a rural community. A smaller upward trend in the national data was observed. There appears to be an association between the rural clerkship experience at MSM and the stated preferred career choices of the students.