A climate threshold for ocean deoxygenation during the Early Cretaceous.

Oceanic anoxic events (OAEs) are historical intervals of global-scale ocean deoxygenation associated with hyperthermal climate states and biological crises1,2. Massive volcanic carbon dioxide (CO2) emissions frequently associated with these events are thought to be a common driver of ocean deoxygenation through several climate-warming-related mechanisms1,3,4. The Early Cretaceous OAE1a is one of the most intense ocean deoxygenation events, persisting for more than 1 Myr (refs. 5,6). However, existing records of marine chemistry and climate across OAE1a are insufficient to fully resolve the timing and dynamics of the underlying processes, thus obscuring cause-and-effect relationships between climate forcing and ocean oxygenation states. Here we show that rapid ocean deoxygenation during OAE1a is linked to volcanic CO2 emissions and the crossing of an associated climate threshold, after which the sluggish pace of the silicate-weathering feedback and climate recovery delayed reoxygenation for >1 Myr. At the end of OAE1a, recrossing this threshold allowed for ocean reoxygenation. Following OAE1a, however, the Earth system remained sufficiently warm such that orbitally forced climate dynamics led to continued cyclic ocean deoxygenation on approximately 100-kyr timescales for another 1 Myr. Our results thus imply a tight coupling between volcanism, weathering and ocean oxygen content that is characterized by a climate threshold.

Clinical heterogeneity and prognostic factors of anti-synthetase syndrome: a multi-centered retrospective cohort study.

OBJECTIVE: Anti-synthetase syndrome (ASyS) patients have heterogeneous clinical manifestations with different initial presentations, complications, and outcomes. This study aimed to assess the clinical characteristics and complications in patients with ASyS, and to identify factors that were associated with the survival of ASyS patients. METHODS: This was a retrospective multicentre longitudinal study. Patients fulfilling either the Connor's criteria or Solomon's criteria for ASyS were recruited. Electronic health records were reviewed until October 2022. Multivariate Cox-regression analysis was used to determine the independent prognostic factors. Auto-antibodies were checked by commercial immunoassays. RESULTS: A total of 205 patients (anti-Jo-1 49.3%, anti-PL-7 19.0%, anti-EJ 11.2%, anti-PL-12 10.2% and anti-OJ 3.4%) were included. The median follow-up time was 4 years. The time from symptoms onset to diagnosis was significantly longer for non-anti-Jo1 patients (median 5 vs 3 months). Common initial presentations included myositis (56.1%), arthritis (54.6%), and interstitial lung disease (ILD) (54.1%). Patients with anti-Jo-1 had significantly higher muscle enzyme levels and more arthritis. All patients with anti-EJ would develop ILD on follow-up and malignancy was noted in 28.6% of the anti-OJ positive patients. 15.6% of the patients died and pulmonary diseases (ILD or pneumonia) were the major causes. Age at diagnosis, malignancy and rapidly progressive-ILD were independently associated with mortality, while joint manifestation was a protective factor. CONCLUSION: In view of the heterogeneity of clinical presentation of ASyS, high index of suspicion and early checking of specific autoantibodies might help prompt diagnosis of ASyS and detection of related complications.

Effect of SARS-CoV2 infection on disease flares in patients with systemic lupus erythematosus: a case-control study.

OBJECTIVES: To study the effect of SARS-CoV2 infection on flares of systemic lupus erythematosus (SLE). METHODS: Patients who fulfilled the ACR/SLICC criteria for SLE and had documented COVID-19 between February and November 2022 were identified retrospectively from our hospital COVID-19 registry. SLE controls who did not have SARS-CoV2 infection were randomly matched for age, sex and the time of infection in a 2:1 ratio with those infected. The primary outcome of interest was clinical flare of SLE within 90 days of COVID-19. The rate of SLE flares (mild/moderate or severe) was compared between SARS-CoV2-infected SLE patients and controls. RESULTS: 91 SLE patients with COVID-19 (age 48.6 ± 14.0 years; 95.6% women) and 182 SLE controls (age 48.7 ± 13.8 years; 95.6% women) were studied. Eleven of 91 (12.1%) SARS-CoV2-infected patients had serious manifestations. One (1.1%) patient died and 7(7.7%) developed severe complications. Within 90 days of SARS-CoV2 infection, 14(15.4%) patients developed mild/moderate clinical SLE flares and 2(2.2%) patients had severe SLE flares. The incidence of SLE flares in SARS-CoV2-infected patients was significantly higher than those without the infection (17.6% vs 5.5%; odds ratio 3.67[1.59-8.46]; p = 0.001). The changes in anti-dsDNA and complement levels, however, were not significantly different between the two groups. Among SARS-CoV2-infected SLE patients, those with clinical SLE flares had significantly lower C3 values (p = 0.004) before the infection than those without. CONCLUSION: Clinical flares within 90 days were significantly more common in SLE patients infected with SARS-CoV2 than matched non-infected SLE controls.

The genome and sex-dependent responses to temperature in the common yellow butterfly, Eurema hecabe.

BACKGROUND: Lepidoptera (butterflies and moths) is one of the most geographically widespread insect orders in the world, and its species play important and diverse ecological and applied roles. Climate change is one of the biggest challenges to biodiversity this century, and lepidopterans are vulnerable to climate change. Temperature-dependent gene expression differences are of relevance under the ongoing climate crisis. However, little is known about how climate affects gene expression in lepidopterans and the ecological consequences of this, particularly with respect to genes with biased expression in one of the sexes. The common yellow butterfly, Eurema hecabe (Family Pieridae), is one of the most geographically widespread lepidopterans that can be found in Asia, Africa, and Australia. Nevertheless, what temperature-dependent effects there may be and whether the effects differ between the sexes remain largely unexplored. RESULTS: Here, we generated high-quality genomic resources for E. hecabe along with transcriptomes from eight developmental stages. Male and female butterflies were subjected to varying temperatures to assess sex-specific gene expression responses through mRNA and microRNA transcriptomics. We find that there are more temperature-dependent sex-biased genes in females than males, including genes that are involved in a range of biologically important functions, highlighting potential ecological impacts of increased temperatures. Further, by considering available butterfly data on sex-biased gene expression in a comparative genomic framework, we find that the pattern of sex-biased gene expression identified in E. hecabe is highly species-specific, rather than conserved across butterfly species, suggesting that sex-biased gene expression responses to climate change are complex in butterflies. CONCLUSIONS: Our study lays the foundation for further understanding of differential responses to environmental stress in a widespread lepidopteran model and demonstrates the potential complexity of sex-specific responses of lepidopterans to climate change.

High and low value care recommended and undertaken prior to knee or hip arthroplasty: a survey study.

INTRODUCTION: National and international clinical practice guidelines have stratified the value of osteoarthritis (OA) interventions. Interventions with strong evidence supporting effectiveness and benefit are 'high value care'. Appointment attendance, audits and practitioner surveys are widely used to determine frequency of recommendations and adherence to high value care. Greater patient reported data is needed in this evidence base. OBJECTIVE: To describe the frequency of high and low value care being recommended and undertaken by individuals awaiting OA-related lower limb arthroplasty. To examine sociodemographic or disease-related variables associated with being recommended different levels of care. METHODS: A cross-sectional survey of 339 individuals was conducted in metropolitan and regional hospitals and surgeon consultation rooms across New South Wales (NSW), Australia. Individuals attending pre-arthroplasty clinics/appointments for primary arthroplasty of the hip and/or knee were invited to participate. Respondents were asked what intervention(s) they were recommended by healthcare practitioners, or other sources of information, and what they had undertaken within two years prior to hip or knee arthroplasty. Interventions were classified as core, recommended, and low value care aligned with the Osteoarthritis Research Society International (OARSI) guidelines. We considered core and recommended interventions high value. The proportion of recommended and undertaken interventions were calculated. We used backwards stepwise multivariate multinomial regression to address aim three. RESULTS: Simple analgesics were most frequently recommended (68% [95% CI 62.9 to 73.1]). 24.8% [20.2 to 29.7] of respondents were recommended high value care only. 75.2% [70.2 to 79.7] of respondents were recommended at least one low value intervention. More than 75% of recommended interventions were undertaken. Respondents awaiting hip arthroplasty, living outside a major city and without private health insurance had greater odds of recommended rather than core interventions being advised. CONCLUSION: While high value interventions are being recommended to individuals living with OA, in most cases they are combined with recommendations for low value care. This is concerning given the high rates of uptake for recommended interventions. Based on patient reported data, disease-related and sociodemographic variables influence the level of care recommended.

Unconventional tonicity-regulated nuclear trafficking of NFAT5 mediated by KPNB1, XPOT and RUVBL2.

NFAT5 is the only known mammalian tonicity-responsive transcription factor with an essential role in cellular adaptation to hypertonic stress. It is also implicated in diverse physiological and pathological processes. NFAT5 activity is tightly regulated by extracellular tonicity, but the underlying mechanisms remain elusive. Here, we demonstrate that NFAT5 enters the nucleus via the nuclear pore complex. We found that NFAT5 utilizes a unique nuclear localization signal (NFAT5-NLS) for nuclear import. siRNA screening revealed that only karyopherin ß1 (KPNB1), but not karyopherin α, is responsible for the nuclear import of NFAT5 via direct interaction with the NFAT5-NLS. Proteomics analysis and siRNA screening further revealed that nuclear export of NFAT5 under hypotonicity is driven by exportin-T (XPOT), where the process requires RuvB-like AAA-type ATPase 2 (RUVBL2) as an indispensable chaperone. Our findings have identified an unconventional tonicity-dependent nucleocytoplasmic trafficking pathway for NFAT5 that represents a critical step in orchestrating rapid cellular adaptation to change in extracellular tonicity. These findings offer an opportunity for the development of novel NFAT5 targeting strategies that are potentially useful for the treatment of diseases associated with NFAT5 dysregulation.

Factors Influencing Gambling Behavior Among Employees in Macau Gambling Industry.

Casino staff of the gambling industry seem to have a higher risk of pathological gambling than the general public because they share many previously identified risk factors, such as easy access to gambling activities. The studies in western countries reported casino staff have a higher prevalence of problematic gambling than the general public. However, some studies in Macau revealed gambling behavior among casino staff is not more common than among other residents there. A quantitative study was conducted with employees of Macau's casinos (N = 714) to understand gambling behavior among casino staff. Structural equation modeling was developed with time spent on gambling as a dependent variable, and awareness of responsible gambling, sensation-seeking tendency, psychological distress, demographic factors, peer/family pressure against gambling, and perception of expected rewards as independent variables. T-test, ANOVA, and correlations were computed for analyzing the obtained data. The structural equation modelling with the time spent on gambling as a dependent variable showed an acceptable model fit (The Chi-square = 5.567, Probability level = .696, CMIN/DF 0.696; NFI = 0.976; NNFI = 1.072; CFI = 1.000; RMSEA = 0.000). Psychological distress, sensation-seeking tendency, peer/family pressure against gambling all have significant effects on time spent on gambling. Perception of expected rewards showed the highest R square in the structural equation modeling and accounted for 77.9% cases of variance for the time spent on gambling. It is predicted that protective factors against pathological gambling include prohibition of gambling in the working venue, a satisfactory salary, and exposure to negative impacts of gambling via their job duties. Given that a high proportion of staff share most risk factors and less than 30% of respondents participated in gambling in the past year, further exploration of the protective factors from casino employees' point of view and further research on casino workers' "expected rewards" are recommended to generate ideas for improving the effectiveness of responsible gambling campaigns in future.

Effects of shoe collar height and arch-support orthosis on joint stability and loading during landing.

This study examined the effects of shoe collar height and foot orthosis on ground reaction force (GRF), ankle and knee mechanics during landing. Sixteen male university basketball players performed drop landing when wearing different shoes with collar height (high vs. low) and foot orthoses (arch-support vs. flat). Biomechanical variables included vertical peak GRF and joint angles and moments in sagittal and coronal planes were analysed with two-way ANOVA with repeated measures (α = 0.05). Results indicated that high-collar shoes had significantly smaller peak ankle dorsiflexion (P < 0.001), smaller ankle sagittal total RoM (P < 0.001), higher forefoot peak GRF (P = 0.009) and peak knee valgus moment (P < 0.001) compared with low-collar shoes. Wearing arch-support orthoses induced higher forefoot peak GRF (P < 0.001) but smaller ankle inversion moment (P = 0.001) compared to flat-orthoses. Furthermore, significant interactions between collar-height and orthosis were found only for initial ankle plantarflexion (P = 0.023) and knee flexion (P = 0.035), but not in any kinetics variables. The findings suggest increased collar height and arch-support orthoses appear to reduce the risks of ankle sprains during landing, but might increase loading at adjacent joints.

RUVBL1/2 Complex Regulates Pro-Inflammatory Responses in Macrophages via Regulating Histone H3K4 Trimethylation.

Macrophages play an important role in the host defense mechanism. In response to infection, macrophages activate a genetic program of pro-inflammatory response to kill any invading pathogen, and initiate an adaptive immune response. We have identified RUVBL2 - an ATP-binding protein belonging to the AAA+ (ATPase associated with diverse cellular activities) superfamily of ATPases - as a novel regulator in pro-inflammatory response of macrophages. Gene knockdown of Ruvbl2, or pharmacological inhibition of RUVBL1/2 activity, compromises type-2 nitric oxide synthase (Nos2) gene expression, nitric oxide production and anti-bacterial activity of mouse macrophages in response to lipopolysaccharides (LPS). RUVBL1/2 inhibitor similarly inhibits pro-inflammatory response in human monocytes, suggesting functional conservation of RUVBL1/2 in humans. Transcriptome analysis further revealed that major LPS-induced pro-inflammatory pathways in macrophages are regulated in a RUVBL1/2-dependent manner. Furthermore, RUVBL1/2 inhibition significantly reduced the level of histone H3K4me3 at the promoter region of Nos2 and Il6, two prototypical pro-inflammatory genes, and diminished the recruitment of NF-kappaB to the corresponding enhancers. Our study reveals RUVBL1/2 as an integral component of macrophage pro-inflammatory responses through epigenetic regulations, and the therapeutic potentials of RUVBL1/2 inhibitors in the treatment of diseases caused by aberrant activation of pro-inflammatory pathways.

Shoe collar height and heel counter-stiffness for shoe cushioning and joint stability in landing.

This study examined the effects of shoe collar-height and counter-stiffness on ground reaction force (GRF), ankle and knee mechanics in landing. Eighteen university basketball players performed drop landing when wearing shoes in different collar height (high vs. low) and counter-stiffness (stiffer vs. less stiff). Biomechanical variables were measured with force platform and motion capturing systems. Two-way repeated measures ANOVA was performed with α = 0.05. Wearing high collar shoes exhibited smaller peak ankle dorsiflexion and total sagittal RoM, peak knee extension moment, but larger peak knee varus moment than the low collar shoes. Stiffer counter-stiffness shoes related to smaller ankle inversion at touchdown and total coronal RoM, but larger peak knee flexion and increased total ankle and knee sagittal RoM than the less stiff counter-stiffness. Furthermore, wearing stiffer counter-stiffness shoes increased forefoot GRF peak at high collar condition, while no significant differences between counter-stiffness at low collar condition. These results suggest that although higher collar height and/or stiffness heel counter used can reduce ankle motion in coronal plane, it would increase the motion and loading at knee joint, which is susceptible to knee injuries. These findings could be insightful for training and footwear development in basketball.

Comparing the prognosis of those with initial shockable and non-shockable rhythms with increasing durations of CPR: Informing minimum durations of resuscitation.

AIM: There is little data to inform the appropriate duration of resuscitation attempts for out-of-hospital cardiac arrest (OHCA). We assessed the relationship of elapsed duration since commencement of resuscitation and outcomes, highlighting differences between initial shockable and non-shockable rhythms. METHODS: We examined consecutive adult non-traumatic EMS-treated OHCA in a single health region. We plotted the time-dependent accrual of patients with ROSC, as well as dynamic estimates of outcomes as a function of duration from commencement of professional resuscitation, and compared subgroups dichotomized by initial rhythm. Logistic regression tested the association between time-to-ROSC and outcomes. RESULTS: Of 1627 adult EMS-treated cases of OHCA, 1617 patients were included; 14% survivors and 10% with favorable neurological outcomes. Time-to-ROSC (per minute increase) was independently associated with survival in those with initial shockable (aOR 0.95, 95% CI 0.92-0.97) and non-shockable (aOR 0.83; 95% CI 0.78-0.88) rhythms. Similar associations were seen with favorable neurologic outcome. The elapsed duration at which the probability of survival fell below 1% was 48 and 15 min in the shockable and non-shockable groups, respectively. Median time-to-termination of resuscitation was 36 and 26 min in the shockable and non-shockable groups, respectively. CONCLUSION: The subgroup of initial shockable rhythms showed a less pronounced association of time-to-ROSC with outcomes, and demonstrated higher resilience for neurologically intact survival after prolonged periods of resuscitation. This data can guide minimum durations of resuscitation, however should not be considered as evidence for termination of resuscitation as survival in this cohort may have been improved with longer resuscitation attempts.

NFAT5 in cellular adaptation to hypertonic stress - regulations and functional significance.

The Nuclear Factor of Activated T Cells-5 (NFAT5), also known as OREBP or TonEBP, is a member of the nuclear factors of the activated T cells family of transcription factors. It is also the only known tonicity-regulated transcription factor in mammals. NFAT5 was initially known for its role in the hypertonic kidney inner medulla for orchestrating a genetic program to restore the cellular homeostasis. Emerging evidence, however, suggests that NFAT5 might play a more diverse functional role, including a pivotal role in blood pressure regulation and the development of autoimmune diseases. Despite the growing significance of NFAT5 in physiology and diseases, our understanding of how its activity is regulated remains very limited. Furthermore, how changes in tonicities are converted into functional outputs via NFAT5 remains elusive. Therefore, this review aims to summarize our current knowledge on the functional roles of NFAT5 in osmotic stress adaptation and the signaling pathways that regulate its activity.

Multi-channel pre-beamformed data acquisition system for research on advanced ultrasound imaging methods.

The lack of open access to the pre-beamformed data of an ultrasound scanner has limited the research of novel imaging methods to a few privileged laboratories. To address this need, we have developed a pre-beamformed data acquisition (DAQ) system that can collect data over 128 array elements in parallel from the Ultrasonix series of research-purpose ultrasound scanners. Our DAQ system comprises three system-level blocks: 1) a connector board that interfaces with the array probe and the scanner through a probe connector port; 2) a main board that triggers DAQ and controls data transfer to a computer; and 3) four receiver boards that are each responsible for acquiring 32 channels of digitized raw data and storing them to the on-board memory. This system can acquire pre-beamformed data with 12-bit resolution when using a 40-MHz sampling rate. It houses a 16 GB RAM buffer that is sufficient to store 128 channels of pre-beamformed data for 8000 to 25 000 transmit firings, depending on imaging depth; corresponding to nearly a 2-s period in typical imaging setups. Following the acquisition, the data can be transferred through a USB 2.0 link to a computer for offline processing and analysis. To evaluate the feasibility of using the DAQ system for advanced imaging research, two proof-of-concept investigations have been conducted on beamforming and plane-wave B-flow imaging. Results show that adaptive beamforming algorithms such as the minimum variance approach can generate sharper images of a wire cross-section whose diameter is equal to the imaging wavelength (150 µm in our example). Also, planewave B-flow imaging can provide more consistent visualization of blood speckle movement given the higher temporal resolution of this imaging approach (2500 fps in our example).

Application of complementary luminescent and fluorescent imaging techniques to visualize nuclear and cytoplasmic Ca²âº signalling during the in vivo differentiation of slow muscle cells in zebrafish embryos under normal and dystrophic conditions.

1. Evidence is accumulating for a role for Ca²âº signalling in the differentiation and development of embryonic skeletal muscle. 2. Imaging of intact, normally developing transgenic zebrafish that express the protein component of the Ca²âº-sensitive complex aequorin, specifically in skeletal muscle, show that two distinct periods of spontaneous synchronised Ca²âº transients occur in the trunk: one at approximately 17.5-19.5 h post-fertilization (h.p.f.; termed signalling period SP1) and the other after approximately 23 h.p.f. (termed SP2). These periods of intense Ca²âº signalling activity are separated by a quiet period. 3. Higher-resolution confocal imaging of embryos loaded with the fluorescent Ca²âº reporter calcium green-1 dextran shows that the Ca²âº signals are generated almost exclusively in the slow muscle cells, the first muscle cells to differentiate, with distinct nuclear and cytoplasmic components. 4. Here, we show that coincidental with the SP1 Ca²âº signals, dystrophin becomes localized to the vertical myoseptae of the myotome. Introduction of a dmd morpholino (dmd-MO) resulted in no dystrophin being expressed in the vertical myoseptae, as well as a disruption of myotome morphology and sarcomere organization. In addition, the Ca²âº signalling signatures of dmd-MO-injected embryos or homozygous sapje mutant embryos were abnormal such that the frequency, amplitude and timing of the Ca²âº signals were altered compared with controls. 5. Our new data suggest that, in addition to a structural role, dystrophin may function in the regulation of [Ca²âº](i) during the early stages of slow muscle cell differentiation when the Ca²âº signals generated in these cells coincide with the first spontaneous contractions of the trunk.

Visualization, characterization and modulation of calcium signaling during the development of slow muscle cells in intact zebrafish embryos.

Intact zebrafish embryos were used as an in vivo animal model to investigate the role of Ca2+ signaling during the differentiation of slow muscle cells (SMCs) within forming skeletal muscle. Transgenic zebrafish were generated using an a-actin promoter that targeted apoaequorin expression specifically to muscle cells. Two distinct Ca2+ signaling periods (CSPs) were visualized in the developing SMCs: between ~17.5-19.5 hours post-fertilization (hpf) and after ~23 hpf, separated by a ~3.5 h Ca2+ signaling quiet period. Further spatial characterization of these Ca2+ signals using confocal fluorescent microscopy and calcium green-1 dextran as a reporter, indicated that the earlier CSP displayed distinct nuclear and cytoplasmic components, whereas the later CSP was predominantly cytoplasmic. Both CSPs consisted of a series of oscillating Ca2+ waves generated at distinct frequencies, while the earlier CSP also displayed a slow rise then fall in the Ca2+ baseline-level. Imaging of cyclopamine- and forskolin-treated wild-type, or smo-/- mutant embryos, where SMCs do not form, confirmed the specific cell population generating the signals. Treating embryos with antagonists indicated that both IP3Rs and RyRs are responsible for generating the temporal characteristics of the Ca2+ signaling signature, and that the latter plays a necessary role in SMC differentiation and subsequent myotome patterning. Together, these data support and extend the proposition that specific spatiotemporal patterns of spontaneous Ca2+ signals might be used for different as well as combinatorial regulation of both nuclear and cytosolic signal transduction cascades, resulting in myofibrillogenesis in SMCs as well as myotome patterning.

Molecular epidemiology and household transmission of community-associated methicillin-resistant Staphylococcus aureus in Hong Kong.

This study evaluated the clinical and epidemiologic features of individuals with community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) in Hong Kong from January 2004 through December 2005. Twenty-four episodes of skin and soft tissue infections and 1 episode of meningitis due to CA-MRSA were identified. CA-MRSA infections or carriage was found in 6 (13%) of 46 household contacts. A total of 29 isolates were analyzed by the Staphylococcus cassette chromosome mec (SCCmec) typing, pulsed-field gel electrophoresis (PFGE), and multilocus sequence typing. In addition, polymerase chain reaction detection of the genes encoding Panton-Valentine leukocidin was also carried out. It was observed that 24 had SCCmec IV/IVA and 5 had SCCmec V, and 23 were pvl positive. PFGE analysis clustered all except 1 isolate into 3 pulsed-field types (PFTs), HKU100 through HKU300. The HKU100 isolates had genotype ST30-IV identical to the Southwest Pacific clone. The HKU200 isolates belonged to ST59-V and were multiresistant, including an ermB-mediated macrolide resistance trait, which is characteristic of the predominant CA-MRSA clone in Taiwan. The HKU300 isolates had unique features (ST8, Panton-Valentine leukocidin negative, and SCCmec IVA) typical of CA-MRSA in Japan. In conclusion, CA-MRSA has a propensity to spread within families. Our findings showed that CA-MRSA strains in Hong Kong have diverse genetic backgrounds.

Effects of nitrogen and sulphide on macroinfaunal community: a microcosm study.

A microcosm experiment was conducted to test the short-term effects of nitrogen (as TKN, total Kjeldahl nitrogen) and sulphide (as AVS, acid volatile sulphide) on macrobenthic infauna over a period of 8 weeks. The experiment consisted of four treatments using sediment cores (D: 8 cm, H: 20 cm) with addition of: I, nitrogen (N) to an in situ mean level of 0.48 mg Ng(-1) dw; II, sulphidic solution (S) to an in situ mean level of 318.8 microM S g(-1) dw; III, nitrogen and sulphidic solution (NS) to in situ mean levels of 0.45 mg Ng(-1) dw and 329.0 microM S g(-1) dw, respectively, and IV, control with no addition of N and S. Sediment cores were retrieved for analysis of infaunal composition after weeks 2, 4 and 8. A total of 646 specimens of macrobenthic infauna belonging to 27 species were recorded from the cores, in which polychaetes were the most abundant with respect to species and individual numbers. Mean species number and diversity H' of the control and N treatment was statistically higher than S and NS treatments, mean individual number of the S treatment was larger than the NS treatment, and mean evenness J of the S treatment was lower than the N and NS treatments as well as the control. Individual numbers also showed a significant increase from weeks 2 to 8, whereas evenness J decreased in weeks 4 and 8. Multivariate analyses of the faunal data suggested that benthic composition of the N treatment and control did not differ during the experimental period, but changes in benthic structure in S and NS treatments were evident. The present findings demonstrated the dose-response relationship of benthic species changes under controlled addition of N and S. The response to N and S additions in the sediment microcosms was in agreement with the general effects of organic enrichment on macrobenthic communities along a spatial gradient of organic pollution as described by Pearson and Rosenberg [Pearson, T.H., Rosenberg, R., 1978. Macrobenthic succession in relation to organic enrichment and pollution of the marine environment. Oceanography and Marine Biology Annual Review 16, 229-311]. However, in the present experiment, community changes in the treatments were observable in a short, temporal scale.

Transient expression of apoaequorin in zebrafish embryos: extending the ability to image calcium transients during later stages of development.

When aequorin is microinjected into cleavage-stage zebrafish embryos, it is largely used up by ~24 hours. Thus, it is currently not possible to image Ca(2+) signals from later stages of zebrafish development using this approach. We have, therefore, developed protocols to express apoaequorin, i.e., the protein component of aequorin, transiently in zebrafish embryos and then reconstitute intact aequorin in vivo by loading the coelenterazine co-factor into the embryos separately. Two types of apoaequorin mRNA, aeq-mRNA and aeq::EGFP-mRNA, the latter containing the enhanced green fluorescent protein (EGFP) sequence, were in vitro transcribed and when these were microinjected into embryos, they successfully translated apoaequorin and a fusion protein of apoaequorin and EGFP (apoaequorin-EGFP), respectively. We show that aeq::EGFP -mRNA was more toxic to embryos than equivalent amounts of aeq-mRNA. In addition, in an in vitro reconstitution assay, apoaequorin-EGFP produced less luminescence than apoaequorin, after reconstitution with coelenterazine and with the addition of Ca(2+). Furthermore, when imaging intact coelenterazine-loaded embryos that expressed apoaequorin, Ca(2+ )signals from ~2.5 to 48 hpf were observed, with the spatio-temporal pattern of these signals up to 24 hpf, being comparable to that observed with aequorin. This transient aequorin expression approach using aeq-mRNA provides a valuable tool for monitoring Ca(2+ )signaling during the 2448 hpf period of zebrafish development. Thus, it effectively extends the aequorin-based Ca(2+) imaging window by an additional 24 hours.

Coronavirus HKU1 and other coronavirus infections in Hong Kong.

We have recently described the discovery of a novel coronavirus, coronavirus HKU1 (CoV-HKU1), associated with community-acquired pneumonia. However, the clinical spectrum of disease and the epidemiology of CoV-HKU1 infections in relation to infections with other respiratory viruses are unknown. In this 12-month prospective study, 4,181 nasopharyngeal aspirates from patients with acute respiratory tract infections were subjected to reverse transcription-PCRs specific for CoV-HKU1 and human coronaviruses NL63 (HCoV-NL63), OC43 (HCoV-OC43), and 229E (HCoV-229E). Coronaviruses were detected in 87 (2.1%) patients, with 13 (0.3%) positive for CoV-HKU1, 17 (0.4%) positive for HCoV-NL63, 53 (1.3%) positive for HCoV-OC43, and 4 (0.1%) positive for HCoV-229E. Of the 13 patients with CoV-HKU1 infections, 11 were children and 8 had underlying diseases. Similar to the case for other coronaviruses, upper respiratory infection was the most common presentation of CoV-HKU1 infections, although pneumonia, acute bronchiolitis, and asthmatic exacerbation also occurred. Despite a shorter duration of fever (mean, 1.7 days) and no difference in maximum temperature in children with CoV-HKU1 infections compared to patients with most other respiratory virus infections, a high incidence of febrile seizures (50%) was noted, which was significantly higher than those for HCoV-OC43 (14%), adenovirus (9%), human parainfluenza virus 1 (0%), and respiratory syncytial virus (8%) infections. CoV-HKU1 and HCoV-OC43 infections peaked in winter, although cases of the former also occurred in spring to early summer. This is in contrast to HCoV-NL63 infections, which mainly occurred in early summer and autumn but were absent in winter. Two genotypes of CoV-HKU1 cocirculated during the study period. Continuous studies over a longer period are warranted to ascertain the seasonal variation and relative importance of the different coronaviruses. Similar studies in other countries are required to better determine the epidemiology and genetic diversity of CoV-HKU1.

Invasive pneumococcal disease burden in Hong Kong children.

In a retrospective, population-based study, we estimated the age-specific incidence of invasive pneumococcal disease in Hong Kong between 1995 and 2004. The incidence rates per 100,000 were 18.3 (95% confidence interval [CI], 13.9-23.3) for children aged