Seasonal extreme temperatures and short-term fine particulate matter increases pediatric respiratory healthcare encounters in a sparsely populated region of the intermountain western United States

BACKGROUND

Western Montana, USA, experiences complex air pollution patterns with predominant exposure sources from summer wildfire smoke and winter wood smoke. In addition, climate change related temperatures events are becoming more extreme and expected to contribute to increases in hospital admissions for a range of health outcomes. Evaluating while accounting for these exposures (air pollution and temperature) that often occur simultaneously and may act synergistically on health is becoming more important.

METHODS

We explored short-term exposure to air pollution on children's respiratory health outcomes and how extreme temperature or seasonal period modify the risk of air pollution-associated healthcare events. The main outcome measure included individual-based address located respiratory-related healthcare visits for three categories: asthma, lower respiratory tract infections (LRTI), and upper respiratory tract infections (URTI) across western Montana for ages 0-17 from 2017-2020. We used a time-stratified, case-crossover analysis with distributed lag models to identify sensitive exposure windows of fine particulate matter (PM2.5) lagged from 0 (same-day) to 14 prior-days modified by temperature or season.

RESULTS

For asthma, increases of 1 µg/m3 in PM2.5 exposure 7-13 days prior a healthcare visit date was associated with increased odds that were magnified during median to colder temperatures and winter periods. For LRTIs, 1 µg/m3 increases during 12 days of cumulative PM2.5 with peak exposure periods between 6-12 days before healthcare visit date was associated with elevated LRTI events, also heightened in median to colder temperatures but no seasonal effect was observed. For URTIs, 1 unit increases during 13 days of cumulative PM2.5 with peak exposure periods between 4-10 days prior event date was associated with greater risk for URTIs visits that were intensified during median to hotter temperatures and spring to summer periods.

CONCLUSIONS

Delayed, short-term exposure increases of PM2.5 were associated with elevated odds of all three pediatric respiratory healthcare visit categories in a sparsely population area of the inter-Rocky Mountains, USA. PM2.5 in colder temperatures tended to increase instances of asthma and LRTIs, while PM2.5 during hotter periods increased URTIs.

Seasonal extreme temperatures and short-term fine particulate matter increases child respiratory hospitalizations in a sparsely populated region of the intermountain western United States

Background

Western Montana, USA, experiences complex air pollution patterns with predominant exposure sources from summer wildfire smoke and winter wood smoke. In addition, climate change related temperatures events are becoming more extreme and expected to contribute to increases in hospital admissions for a range of health outcomes. Few studies have evaluated these exposures (air pollution and temperature) that often occur simultaneously and may act synergistically on health.

Methods

We explored short-term exposure to air pollution on childhood respiratory health outcomes and how extreme temperature or seasonal period modify the risk of air pollution-associated hospitalizations. The main outcome measure included all respiratory-related hospital admissions for three categories: asthma, lower respiratory tract infections (LRTI), and upper respiratory tract infections (URTI) across western Montana for all individuals aged 0-17 from 2017-2020. We used a time-stratified, case-crossover analysis and distributed lag models to identify sensitive exposure windows of fine particulate matter (PM2.5) lagged from 0 (same-day) to 15 prior-days modified by temperature or season.

Results

Short-term exposure increases of 1 μg/m3 in PM2.5 were associated with elevated odds of all three respiratory hospital admission categories. PM2.5 was associated with the largest increased odds of hospitalizations for asthma at lag 7-13 days [1.87(1.17-2.97)], for LRTI at lag 6-12 days [2.18(1.20-3.97)], and for URTI at a cumulative lag of 13 days [1.29(1.07-1.57)]. The impact of PM2.5 varied by temperature and season for each respiratory outcome scenario. For asthma, PM2.5 was associated most strongly during colder temperatures [3.11(1.40-6.89)] and the winter season [3.26(1.07-9.95)]. Also in colder temperatures, PM2.5 was associated with increased odds of LRTI hospitalization [2.61(1.15-5.94)], but no seasonal effect was observed. Finally, 13 days of cumulative PM2.5 prior to admissions date was associated with the greatest increased odds of URTI hospitalization during summer days [3.35(1.85-6.04)] and hotter temperatures [1.71(1.31-2.22)].

Conclusions

Children's respiratory-related hospital admissions were associated with short-term exposure to PM2.5. PM2.5 associations with asthma and LRTI hospitalizations were strongest during cold periods, whereas associations with URTI were largest during hot periods.

Classification

environmental public health, fine particulate matter air pollution, respiratory infections.

Providing APPE pharmacy students rural health assessment experience following wildfire event in western Montana

BACKGROUND AND PURPOSE

We describe a novel, interprofessional, experiential training involving pharmacy students in response to a health emergency in rural Montana (MT).

EDUCATIONAL ACTIVITY AND SETTING

Fourth-year pharmacy students on clinical rotations were recruited to participate in screening events assessing effects of wildfire smoke in Seeley Lake, MT. Students were required to fulfill at least two hours of supplementary training in addition to education on human research guidelines. Students assisted with patient surveys (demographics, health, and respiratory), physiological testing with biomedical researchers, blood pressure and medication counseling, and spirometry specialists.

FINDINGS

At least 20 pharmacy students have participated in this project in addition to nursing (n = 8), public health (n = 1), and social work (n = 1) students. In initial and subsequent screenings, students worked alongside a team of biomedical researchers and faculty from the University of Montana. An initial cohort of 95 patients was recruited.

SUMMARY

This unique experiential training opportunity has afforded pharmacy students access to rural community patient interaction and exposure to and performance of a variety of tests in response to an environmental health emergency. Furthermore, it enabled health professionals and researchers to assess individual and overall community health following an extreme wildfire smoke event, providing the groundwork for utilization of pharmacy students in healthcare responses to public health emergencies.

Why invest in Research & Development for sorghum and millets? The business case for East and Southern Africa

This article synthesizes recent research by ICRISAT and its partners to analyse the business case for sorghum and millets in ESA and the wider strategy of commercialization on which this is based. The business case is stronger for sorghum because of its greater impact on poverty and food security, but millets are better suited to a strategy of commercialization. Commercial demand for millets is primarily driven by specialty markets for flour while that for sorghum is limited to beer. Demand for improved varieties is driven primarily by the need for early - maturity that shortens the hungry period. Future growth in production depends on increased opportunities for inter-regional trade.

Sustained Effects on Lung Function in Community Members Following Exposure to Hazardous PM2.5 Levels from Wildfire Smoke

Extreme wildfire events are becoming more common and while the immediate risks of particulate exposures to susceptible populations (i.e., elderly, asthmatics) are appreciated, the long-term health effects are not known. In 2017, the Seeley Lake (SL), MT area experienced unprecedented levels of wildfire smoke from July 31 to September 18, with a daily average of 220.9 μg/m³. The aim of this study was to conduct health assessments in the community and evaluate potential adverse health effects. The study resulted in the recruitment of a cohort (n = 95, average age: 63 years), for a rapid response screening activity following the wildland fire event, and two follow-up visits in 2018 and 2019. Analysis of spirometry data found a significant decrease in lung function (FEV₁/FVC ratio: forced expiratory volume in first second/forced vital capacity) and a more than doubling of participants that fell below the lower limit of normal (10.2% in 2017 to 45.9% in 2018) one year following the wildfire event, and remained decreased two years (33.9%) post exposure. In addition, observed FEV₁ was significantly lower than predicted values. These findings suggest that wildfire smoke can have long-lasting effects on human health. As wildfires continue to increase both here and globally, understanding the health implications is vital to understanding the respiratory impacts of these events as well as developing public health strategies to mitigate the effects.

Evaluation of a muscle pump-activating device for non-healing venous leg ulcers

This evaluation involves an innovative muscle pump‐activating device (geko™) as an adjunctive therapy with best practices for non‐healing venous leg ulcers (VLUs). Stimulating the common peroneal nerve (at the fibular head), the geko™ device creates a response that acts as foot and calf muscle pumps, increasing venous, arterial and microcirculatory flow. The aim was to evaluate and determine if the geko™ is effective in this population and if it should be added to the medical supply formulary. In all, 12 patients with 18 recalcitrant VLUs (defined as less than 30% reduction in wound size in 30 days with best practices) in two community settings in Ontario consented to the evaluation and were treated with the geko™ for up to 20 weeks.

A total of 44% of wounds healed, and 39% decreased in size. One patient non‐adherent with the geko™ and best practices had deterioration in his or her wounds. With the patients as their own control, the mean weekly healing rate with the geko™ was 9·35% (±SD 0·10) compared to 0·06% (±SD 0·10) prior to baseline, which was statistically significant (P < 0·01). Three patients not in optimal therapy increased compression due to decreased pain, further enabling healing. This study was not a randomised investigation, although the patients acted as their own controls. A pragmatic evaluation reflects the reality of the community sector; in spite of best practices or evidence‐based care, therapy is not uniformly applied, with some participants unable to tolerate or indeed comply with optimal compression therapy. Rash occurred under the devices in 7 of 12 (58%) patients. One patient stopped the device due to rash, while another had to take breaks from using the device. Subsequently, the manufacturer (FirstKind Ltd) has developed a new device and protocol specific to the requirements of wound therapy to minimise this response.

This small case series demonstrated the highly significant effectiveness of the geko™ device in these hard‐to‐heal VLUs. Further evaluations to determine dose and patient selection criteria are underway.

Plasmakristall-4: New complex (dusty) plasma laboratory on board the International Space Station

New complex-plasma facility, Plasmakristall-4 (PK-4), has been recently commissioned on board the International Space Station. In complex plasmas, the subsystem of μm-sized microparticles immersed in low-pressure weakly ionized gas-discharge plasmas becomes strongly coupled due to the high (10³-10⁴ e) electric charge on the microparticle surface. The microparticle subsystem of complex plasmas is available for the observation at the kinetic level, which makes complex plasmas appropriate for particle-resolved modeling of classical condensed matter phenomena. The main purpose of PK-4 is the investigation of flowing complex plasmas. To generate plasma, PK-4 makes use of a classical dc discharge in a glass tube, whose polarity can be switched with the frequency of the order of 100 Hz. This frequency is high enough not to be felt by the relatively heavy microparticles. The duty cycle of the polarity switching can be also varied allowing to vary the drift velocity of the microparticles and (when necessary) to trap them. The facility is equipped with two videocameras and illumination laser for the microparticle imaging, kaleidoscopic plasma glow observation system and minispectrometer for plasma diagnostics and various microparticle manipulation devices (e.g., powerful manipulation laser). Scientific experiments are programmed in the form of scripts written with the help of specially developed C scripting language libraries. PK-4 is mainly operated from the ground (control center CADMOS in Toulouse, France) with the support of the space station crew. Data recorded during the experiments are later on delivered to the ground on the removable hard disk drives and distributed to participating scientists for the detailed analysis.

Does anaesthesia with nitrous oxide affect mortality or cardiovascular morbidity? A systematic review with meta-analysis and trial sequential analysis

BACKGROUND

The role of nitrous oxide in modern anaesthetic practice is contentious. One concern is that exposure to nitrous oxide may increase the risk of cardiovascular complications. ENIGMA II is a large randomized clinical trial currently underway which is investigating nitrous oxide and cardiovascular complications. Before the completion of this trial, we performed a systematic review and meta-analysis, using Cochrane methodology, on the outcomes that make up the composite primary outcome.

METHODS

We used conventional meta-analysis and trial sequential analysis (TSA). We reviewed 8282 abstracts and selected 138 that fulfilled our criteria for study type, population, and intervention. We attempted to contact the authors of all the selected publications to check for unpublished outcome data.

RESULTS

Thirteen trials had outcome data eligible for our outcomes. We assessed three of these trials as having a low risk of bias. Using conventional meta-analysis, the relative risk of short-term mortality in the nitrous oxide group was 1.38 [95% confidence interval (CI) 0.22-8.71] and the relative risk of long-term mortality in the nitrous oxide group was 0.94 (95% CI 0.80-1.10). In both cases, TSA demonstrated that the data were far too sparse to make any conclusions. There were insufficient data to perform meta-analysis for stroke, myocardial infarct, pulmonary embolus, or cardiac arrest.

CONCLUSION

This systematic review demonstrated that we currently do not have robust evidence for how nitrous oxide used as part of general anaesthesia affects mortality and cardiovascular complications.

Feeding Artemisia annua alters digesta pH and muscle lipid oxidation products in broiler chickens

Because of growing consumer concern about the use of antimicrobials and the ban on most antibiotic feed additives in the European Union, there is increased interest in using alternatives to antimicrobials in poultry diets. Dried leaves of Artemisia annua have been used in Oriental medicine due to their antimicrobial activities. In the current study, the effect of including A. annua in broiler diets on hindgut and ceca pH, lipid oxidation products, and phenolic content of dark and white meat, and bird performance were investigated. A total of 96 broiler chicks were kept in 48 cages. Two cages with 2 birds per each cage are considered as 1 replicate, and there were 8 replications per treatment. The birds were fed corn-soy diets containing 0% (control), 2% (ART2), or 4% (ART4) dried A. annua leaves from d 14 through d 42. Cecal digesta pH was the lowest in birds fed the ART4 diet (P < 0.02), whereas the pH of ileal digesta was the lowest in ART2 (P < 0.01). Lipid oxidation products measured as TBA reactive substances (TBARS) were lower in the breast and thigh muscle of birds fed ART2 and ART4 diets compared with the control (P < 0.0001). No difference was found in total fat content of the liver, abdominal fat pads, or breast or thigh muscle content (P > 0.05). Artemisia annua addition did not affect final BW, weight gain, feed consumption, carcass weight, or feed:gain. No difference was observed in the relative weight of liver, abdominal fat, spleen, or heart tissue. Gastric acidity is protective against intestinal colonization and translocation of pathogenic bacteria. Therefore, gut pH and muscle tissue TBARS reduction in birds fed ART2 and ART4 suggest that A. annua may prove useful as a natural phytogenic feed additive with antioxidant potential that could be incorporated into poultry diets.

Depressed mood through women's reproductive cycle: correlation to mood at menopause

OBJECTIVES

Depressive symptoms are frequent through the different stages of a woman's reproductive cycle. The aim of this study was to evaluate a possible correlation of depressive mood before menstruation, during pregnancy, after delivery and around the menopause.

METHODS

The sample consisted of 110 women (mean age 52 years, standard deviation 4 years) who rated their mood at present and retrospectively at different stages of the reproductive cycle. Mood was rated using a visual analogue scale.

RESULTS

A significant statistical association was found between the present mood and mood at the premenstrual period, but not with mood at pregnancy or after delivery. These findings were independent of age, menopausal status or use of hormone replacement therapy.

CONCLUSIONS

The statistical association between depressed mood around menopause and before menstruation supports the assumption that there is a common etiology, which could be attributed to hormonal or psychological factors, or both.

The use of ketamine as rescue analgesia in the recovery room following morphine administration--a double-blind randomised controlled trial in postoperative patients

In some patients, control of postoperative pain can be difficult with morphine alone. This double-blind randomised controlled trial was designed to evaluate whether a small bolus dose of ketamine could improve pain scores in those patients who had inadequate relief of their postoperative pain after two standard doses of morphine. Forty-one patients with uncontrolled postoperative pain were randomly assigned to receive either morphine (M) alone, or morphine plus 0.25 mg/kg ketamine (K) in the recovery room. No other analgesics were to be given. The study had adequate power to detect a 25% difference in pain scores. There was no statistically significant difference in verbal rating scale pain scores between the two groups either in the recovery room (K = 5.16, M = 6.28, P = 0.065), or at a later time on the ward. There was no apparent difference between groups in sedation, morphine consumption, postoperative nausea and vomiting, quality of recovery or need for rescue analgesia. We could not demonstrate an effective role for ketamine in the management of problematic postoperative pain at the dose studied.

The use of Ketamine as Rescue Analgesia in the Recovery Room following Morphine Administration—A Double-Blind Randomised Controlled Trial in Postoperative Patients

In some patients, control of postoperative pain can be difficult with morphine alone. This double-blind randomised controlled trial was designed to evaluate whether a small bolus dose of ketamine could improve pain scores in those patients who had inadequate relief of their postoperative pain after two standard doses of morphine. Forty-one patients with uncontrolled postoperative pain were randomly assigned to receive either morphine (M) alone, or morphine plus 0.25 mg/kg ketamine (K) in the recovery room. No other analgesics were to be given. The study had adequate power to detect a 25% difference in pain scores. There was no statistically significant difference in verbal rating scale pain scores between the two groups either in the recovery room (K=5.16, M=6.28, P=0.065), or at a later time on the ward. There was no apparent difference between groups in sedation, morphine consumption, postoperative nausea and vomiting, quality of recovery or need for rescue analgesia. We could not demonstrate an effective role for ketamine in the management of problematic postoperative pain at the dose studied.

Treatment of urinary incontinence in cystic fibrosis

BACKGROUND

Urinary incontinence (UI) is a newly recognised problem in cystic fibrosis. Whilst prevalence is well documented, there are no reports of assessment and treatment of the problem.

METHODS

A previous study reports the prevalence of UI in women with CF to be 51/75 (68%). Nineteen women subsequently requested help for the problem and were referred to a physiotherapist specialising in women's health. A digital assessment was performed to measure pelvic floor muscle strength and endurance. An individualised programme of pelvic floor muscle exercises (PFME) was taught based on the assessment. A questionnaire addressed issues of assessment and treatment.

RESULTS

12 women were assessed. The median (range) age, FEV1% predicted and BMI were 20.9 (19.3-46.1) years, 45.9 (14.8-82.7) and 20.5 (16.1-26.0), respectively. The median strength of the pelvic floor muscle was moderate (Oxford Scale grade 3) with a hold time (endurance) of 5 s. At reassessment (median time 13.1 weeks), there was an improvement in endurance (P = 0.04), with no change in strength. This was supported by a subjective improvement in symptoms. Patients found the exercises were difficult to perform, difficult to fit into their treatment programme and adherence was poor.

CONCLUSIONS

PFME are effective at improving endurance and reducing leakage over the short-term. Women are reluctant to be assessed and the CF team should provide support and encouragement with treatment. Long-term outcome and the mechanisms of UI in this group of patients need further evaluation.

Arylisothiocyanate-containing esters of caffeic acid designed as affinity ligands for HIV-1 integrase

Integrase is an enzyme found in human immunodeficiency virus, which is required for the viral life cycle, yet has no human cellular homologue. For this reason, HIV integrase (IN) has become an important target for the development of new AIDS therapeutics. Irreversible affinity ligands have proven to be valuable tools for studying a number of enzyme and protein systems, yet to date there have been no reports of such affinity ligands for the study of IN. As an initial approach toward irreversible ligand design directed against IN, we appended isothiocyanate functionality onto caffeic acid phenethyl ester (CAPE), a known HIV integrase inhibitor. The choice of isothiocyanate as the reactive functionality, was based on its demonstrated utility in the preparation of affinity ligands directed against a number of other protein targets. Several isomeric CAPE isothiocyanates were prepared to explore the enzyme topography for reactive nitrogen and sulfur nucleophiles vicinal to the enzyme-bound CAPE. The preparation of these CAPE isothiocyanates, required development of new synthetic methodology which employed phenyl thiocarbamates as latent isothiocyanates which could be unmasked near the end of the synthetic sequence. When it was observed that beta-mercaptoethanol (beta-ME), which is required to maintain the catalytic activity of soluble IN (a F185KC280S mutant), reacted with CAPE isothiocyanate functionality to form the corresponding hydroxyethylthiocarbamate, a variety of mutant IN were examined which did not require the presence of beta-ME for catalytic activity. Although in these latter enzymes, CAPE isothiocyanate functionality was presumed to be present and available for acylation by IN nucleophiles, they were equally effective against Cys to Ser mutants. One conclusion of these studies, is that upon binding of CAPE to the integrase, nitrogen or sulfur nucleophiles may not be properly situated in the vicinity of the phenethyl aryl ring to allow reaction with and covalent modification of reactive functionality, such as isothiocyanate groups. The fact that introduction of the isothiocyanate group onto various positions of the phenethyl ring or replacement of the phenyl ring with naphthyl rings, failed to significantly affect inhibitory potency, indicates a degree of insensitivity of this region of the molecule toward structural modification. These findings may be useful in future studies concerned with the development and use of HIV-1 integrase affinity ligands.

Questionnaire survey of urinary incontinence in women with cystic fibrosis

Cystic fibrosis is an inherited disease characterised by the production of infected secretions, and it requires lifelong daily treatment by airway clearance. We knew that some women attending our clinic for adults with cystic fibrosis leaked urine when performing airway clearance or spirometry, but they were dismissive during discussion and were rarely forthcoming about the problem. This study was designed to determine the prevalence of urinary incontinence in women with cystic fibrosis, to establish the importance of the problem as perceived by the patients, and to identify those women who wanted help.

The amino acid sequence of the PKR-eIF2alpha phosphorylation homology domain of hepatitis C virus envelope 2 protein and response to interferon-alpha

A region of the hepatitis C virus (HCV) envelope 2 protein, the protein kinase, PKR and early initiation factor 2alpha phosphorylation homology domain (PePHD), may be important in interferon (IFN)-alpha resistance. The PePHD was amplified by polymerase chain reaction and sequenced, and the amino acid sequence derived from pretreatment serum of 14 genotype 3-infected patients with a range of responses to IFN-alpha therapy. Only 1 patient had a PePHD variant. IFN-resistant PePHD variants present at low titers in pretreatment serum should be selected by therapy; therefore, the PePHD amino acid sequence was also obtained from serum collected during or after treatment in 5 patients with breakthrough or relapse of HCV RNA positivity. No difference was found between the pre- and posttreatment PePHD sequences. Thus, it appears that pretreatment sequencing of the PePHD would not enable clinicians to predict the treatment response. There was no evidence that IFN therapy exerts selection pressure in this region.

Identification of HIV-1 integrase inhibitors via three-dimensional database searching using ASV and HIV-1 integrases as targets

Integration of viral DNA into the host cell genome is a critical step in the life cycle of HIV. This essential reaction is catalyzed by integrase (IN) through two steps, 3'-processing and DNA strand transfer. Integrase is an attractive target for drug design because there is no known cellular analogue and integration is essential for successful replication of HIV. A computational three-dimensional (3-D) database search was used to identify novel HIV-1 integrase inhibitors. Starting from the previously identified Y3 (4-acetylamino-5-hydroxynaphthalene-2,7-disulfonic acid) binding site on the avian sarcoma virus integrase (ASV IN), a preliminary search of all compounds in the nonproprietary, open part of the National Cancer Institute 3-D database yielded a collection of 3100 compounds. A more rigorous scoring method was used to rescreen the 3100 compounds against both ASV IN and HIV-1 IN. Twenty-two of those compounds were selected for inhibition assays against HIV-1 IN. Thirteen of the 22 showed inhibitory activity against HIV-1 IN at concentrations less than 200 microM and three of them showed antiviral activities in HIV-1 infected CEM cells with effective concentrations (EC50) ranging from 0.8 to 200 microM. Analysis of the computer-generated binding modes of the active compounds to HIV-1 IN showed that simultaneous interaction with the Y3 site and the catalytic site is possible. In addition, interactions between the active compounds and the flexible loop involved in the binding of DNA by IN are indicated to occur. The structural details and the unique binding motif between the HIV-1 IN and its inhibitors identified in the present work may contribute to the future development of IN inhibitors.

Cell cycle regulation of PML modification and ND10 composition

The nuclear sub-structures known as ND10, PODs or PML nuclear bodies can be rapidly modified by diverse stimuli, and the resultant structural changes correlate with events such as cellular transformation and successful virus infection. We show that the ND10 components PML and Sp100 undergo profound biochemical changes during the cell cycle. Both proteins are conjugated to the ubiquitin-like protein SUMO-1 during interphase, but they become de-conjugated during mitosis and an isoform of PML of distinct electrophoretic mobility appears. This mitosis-specific form of PML is highly labile in vitro, but is partially stabilised by phosphatase inhibitors. Treatment of interphase cells with phosphatase inhibitors induces the production of a PML isoform of similar gel mobility to the mitosis-specific species, and taken together these results suggest that phosphorylation is an important factor in the differential modification of PML during the cell cycle. PML and Sp100 normally tightly co-localise in ND10 in interphase cells, but they become separated during mitosis. Interphase cells treated with phosphatase inhibitors or subjected to heat shock also show structural changes in ND10, accompanied by alterations to the normal pattern of PML modification. Taken with previous findings on the effects of infection by herpes simplex virus and adenovirus on ND10 structure and PML modification, these results suggest that the many factors which have been shown to modify ND10 structure may do so by interaction with the biochemical mechanisms that act on ND10 components during the cell cycle.

A dynamic connection between centromeres and ND10 proteins

ND10, otherwise known as nuclear dots, PML nuclear bodies or PODs, are punctate foci in interphase nuclei that contain several cellular proteins. The functions of ND10 have not been well defined, but they are sensitive to external stimuli such as stress and virus infection, and they are disrupted in malignant promyelocytic leukaemia cells. Herpes simplex virus type 1 regulatory protein Vmw110 induces the proteasome-dependent degradation of ND10 component proteins PML and Sp100, particularly the species of these proteins which are covalently conjugated to the ubiquitin-like protein SUMO-1. We have recently reported that Vmw110 also induces the degradation of centromere protein CENP-C with consequent disruption of centromere structure. These observations led us to examine whether there were hitherto undetected connections between ND10 and centromeres. In this paper we report that hDaxx and HP1 (which have been shown to interact with CENP-C and Sp100, respectively) are present in a proportion of both ND10 and interphase centromeres. Furthermore, the proteasome inhibitor MG132 induced an association between centromeres and ND10 proteins PML and Sp100 in a significant number of cells in the G(2) phase of the cell cycle. These results imply that there is a dynamic, cell cycle regulated connection between centromeres and ND10 proteins which can be stabilised by inhibition of proteasome-mediated proteolysis.

A novel PAX6 frameshift mutation in a kindred from Atlantic Canada with familial aniridia

BACKGROUND

Many mutations in PAX6, a member of a family of genes essential for normal development, have been described. We carried out a study to identify the mutation in PAX6 responsible for aniridia, an autosomal dominant disorder, in a kindred from Atlantic Canada.

METHODS

Polymerase chain reaction amplification of coding exons, single-strand conformation polymorphism analysis and DNA sequencing.

RESULTS

A novel deletion of an adenosine residue at position 1030 (1030delA) was detected.

INTERPRETATION

The mutation responsible for aniridia in this kindred is expected to cause a frameshift in the PAX6 coding sequence and truncation of the homeodomain, which is essential for the function of the pax6 protein.

Thiazolothiazepine inhibitors of HIV-1 integrase

A series of thiazolothiazepines were prepared and tested against purified human immunodeficiency virus type-1 integrase (HIV-1 IN) and viral replication. Structure-activity studies reveal that the compounds possessing the pentatomic moiety SC(O)CNC(O) with two carbonyl groups are in general more potent against purified IN than those containing only one carbonyl group. Substitution with electron-donating or -withdrawing groups did not enhance nor abolish potency against purified IN. By contrast, compounds with a naphthalene ring system showed enhanced potency, suggesting that a hydrophobic pocket in the IN active site might accommodate an aromatic system rather than a halogen. The position of sulfur in the thiazole ring appears important for potency against IN, as its replacement with an oxygen or carbon abolished activity. Further extension of the thiazole ring diminished potency. Compounds 1, 19, and 20 showed antiviral activity and inhibited IN within similar concentrations. These compounds inhibited IN when Mn(2+) or Mg(2+) was used as cofactor. None of these compounds showed detectable activities against HIV-1 reverse transcriptase, protease, virus attachment, or nucleocapsid protein zinc fingers. Therefore, thiazolothiazepines are potentially important lead compounds for development as inhibitors of IN and HIV replication.

BLyS: member of the tumor necrosis factor family and B lymphocyte stimulator

The tumor necrosis factor (TNF) superfamily of cytokines includes both soluble and membrane-bound proteins that regulate immune responses. A member of the human TNF family, BLyS (B lymphocyte stimulator), was identified that induced B cell proliferation and immunoglobulin secretion. BLyS expression on human monocytes could be up-regulated by interferon-gamma. Soluble BLyS functioned as a potent B cell growth factor in costimulation assays. Administration of soluble recombinant BLyS to mice disrupted splenic B and T cell zones and resulted in elevated serum immunoglobulin concentrations. The B cell tropism of BLyS is consistent with its receptor expression on B-lineage cells. The biological profile of BLyS suggests it is involved in monocyte-driven B cell activation.

The ability of herpes simplex virus type 1 immediate-early protein Vmw110 to bind to a ubiquitin-specific protease contributes to its roles in the activation of gene expression and stimulation of virus replication

Herpes simplex virus type 1 immediate-early protein Vmw110 stimulates the onset of virus infection and is required for efficient reactivation from latency. In transfection assays, Vmw110 is a potent activator of gene expression, but its mode of action has yet to be determined. Previous work has shown that Vmw110 localizes to specific intranuclear structures known as ND10, PML bodies, or PODs and causes the disruption of these domains. The ability of Vmw110 to disrupt ND10 correlates with its biological activities in infected and transfected cells. It has also been found that Vmw110 binds strongly and specifically to a ubiquitin-specific protease known as HAUSP, itself a component of a subset of ND10. In this study we have investigated the role of HAUSP in Vmw110 activity; single amino acid residues of Vmw110 required for the interaction were identified, and the effects of mutation of these residues in infected and transfected cells were then assayed. The results indicate that the ability to bind to HAUSP contributes to the functional activities of Vmw110.

A viral activator of gene expression functions via the ubiquitin-proteasome pathway

The ability of herpes simplex virus type 1 (HSV-1) to attain a latent state in sensory neurones and reactivate periodically is crucial for its biological and clinical properties. The active transcription of the entire 152 kb viral genome during lytic replication contrasts with the latent state, which is characterized by the production of a single set of nuclear-retained transcripts. Reactivation of latent genomes to re-initiate the lytic cycle therefore involves a profound change in viral transcriptional activity, but the mechanisms by which this fundamentally important process occurs are yet to be well understood. In this report we show that the stimulation of the onset of viral lytic infection mediated by the viral immediate-early (IE) protein Vmw110 is strikingly inhibited by inactivation of the ubiquitin-proteasome pathway. Similarly, the Vmw110-dependent reactivation of quiescent viral genomes in cultured cells is also dependent on proteasome activity. These results constitute the first demonstration that the transcriptional activity of a viral genome can be regulated by protein stability control pathways.

Identification of HIV-1 integrase inhibitors based on a four-point pharmacophore

The rapid emergence of human immunodeficiency virus (HIV) strains resistant to available drugs implies that effective treatment modalities will require the use of a combination of drugs targeting different sites of the HIV life cycle. Because the virus cannot replicate without integration into a host chromosome, HIV-1 integrase (IN) is an attractive therapeutic target. Thus, an effective IN inhibitor should provide additional benefit in combination chemotherapy. A four-point pharmacophore has been identified based on the structures of quinalizarin and purpurin, which were found to be potent IN inhibitors using both a preintegration complex assay and a purified enzyme assay in vitro. Searching with this four-point pharmacophore in the 'open' part of the National Cancer Institute three-dimensional structure database produced 234 compounds containing the pharmacophore. Sixty of these compounds were tested for their inhibitory activity against IN using the purified enzyme; 19 were found to be active against IN with IC50 values of less than 100 microM, among which 10 had IC50 values of less than 10 microM. These inhibitors can further serve as leads, and studies are in progress to design novel inhibitors based on the results presented in this study.

The disruption of ND10 during herpes simplex virus infection correlates with the Vmw110- and proteasome-dependent loss of several PML isoforms

The small nuclear structures known as ND10 or PML nuclear bodies have been implicated in a variety of cellular processes including response to stress and interferons, oncogenesis, and viral infection, but little is known about their biochemical properties. Recently, a ubiquitin-specific protease enzyme (named HAUSP) and a ubiquitin-homology family protein (PIC1) have been found associated with ND10. HAUSP binds strongly to Vmw110, a herpesvirus regulatory protein which has the ability to disrupt ND10, while PIC1 was identified as a protein which interacts with PML, the prototype ND10 protein. We have investigated the role of ubiquitin-related pathways in the mechanism of ND10 disruption by Vmw110 and the effect of virus infection on PML stability. The results show that the disruption of ND10 during virus infection correlates with the loss of several PML isoforms and this process is dependent on active proteasomes. The PML isoforms that are most sensitive to virus infection correspond closely to those which have recently been identified as being covalently conjugated to PIC1. In addition, a large number of PIC1-protein conjugates can be detected following transfection of a PIC1 expression plasmid, and many of these are also eliminated in a Vmw110-dependent manner during virus infection. These observations provide a biochemical mechanism to explain the observed effects of Vmw110 on ND10 and suggest a simple yet powerful mechanism by which Vmw110 might function during virus infection.

Organogenesis of Fascicled ear mutant inflorescences in maize (Poaceae)

The ontogeny of staminate tassels and pistillate ears in the maize mutant Fascicled ear was examined using scanning electron microscopy. The normal pattern of inflorescence development is perturbed by the Fascicled ear mutation at the transition stage. The Fascicled ear mutation promotes the development of an abnormal transition stage axis that is both shorter and broader than the wild type. The inflorescence apical meristem then undergoes a bifurcation, and two inflorescence axes arise in place of a single axis. Each derived inflorescence apical meristem may undergo a similar perturbation sequence. This expression of the Fascicled ear mutation may be repeated one to several times, which leads to the development of a fascicled pistillate inflorescence and a fascicled central spike in the staminate inflorescence. The apical meristems of some tassel branches are also bifurcated. Subsequent organogenesis during paired-spikelet and floral development in Fascicled ear plants follows the pattern of normal maize. However, triplet spikelets are occasionally observed. The organogenic disruption by the Fascicled ear mutation that we describe will aid genetic and molecular analysis on the regulation of inflorescence development in maize and other members of the genus Zea.

Depression after childbirth: the views of medical students and women compared

BACKGROUND

Little research has been conducted on the views of health professionals about women's experiences of depression after childbirth. This study compared the views held by undergraduate medical students about postnatal depression with those of women who had themselves experienced it.

METHODS

Fourth- and sixth-year medical students at one Australian university were surveyed (n = 134). Their views about prevalence, duration, contributing factors, and advice for dealing with postnatal depression were compared with the findings from 60 women in a population-based study of mothers who gave birth in Victoria in 1989, in which women scoring as depressed 8 to 9 months after birth on the Edinburgh Postnatal Depression Scale were interviewed 12 to 18 months later about their experiences of depression and their advice to other mothers.

RESULTS

Women's and students' views differed markedly, with students much more likely to view hormonal and biologic factors and a "tendency to depression" as playing an important role than women who identified a wide range of social, physical health, and life event factors as contributing to their experience of depression. Fourth-year students tended to overestimate the prevalence of depression and sixth-year students to underestimate it. Both groups underestimated the duration of depression compared with women's actual experiences.

CONCLUSION

Medical students need to develop a broader understanding of maternal depression after the birth of a baby, and women's own views of the experience can and should make an important contribution to medical teaching on this topic.

A novel ubiquitin-specific protease is dynamically associated with the PML nuclear domain and binds to a herpesvirus regulatory protein

Herpes simplex virus type 1 immediate-early protein Vmw110 is a non-specific activator of gene expression and is required for efficient initiation of the viral lytic cycle. Since Vmw110-deficient viruses reactivate inefficiently in mouse latency models it has been suggested that Vmw110 plays a role in the balance between the latent and lytic states of the virus. The mechanisms by which Vmw110 achieves these functions are poorly understood. Vmw110 migrates to discrete nuclear structures (ND10) which contain the cellular PML protein, and in consequence PML and other constituent proteins are dispersed. In addition, Vmw110 binds to a cellular protein of approximately 135 kDa, and its interactions with the 135 kDa protein and ND10 contribute to its ability to stimulate gene expression and viral lytic growth. In this report we identify the 135 kDa protein as a novel member of the ubiquitin-specific protease family. The protease is distributed in the nucleus in a micropunctate pattern with a limited number of larger discrete foci, some of which co-localize with PML in ND10. At early times of virus infection, the presence of Vmw110 increases the proportion of ND10 which contain the ubiquitin-specific protease. These results identify a novel, transitory component of ND10 and implicate a previously uncharacterized ubiquitin-dependent pathway in the control of viral gene expression.

A novel ubiquitin-specific protease is dynamically associated with the PML nuclear domain and binds to a herpesvirus regulatory protein

Herpes simplex virus type 1 immediate-early protein Vmw110 is a non-specific activator of gene expression and is required for efficient initiation of the viral lytic cycle. Since Vmw110-deficient viruses reactivate inefficiently in mouse latency models it has been suggested that Vmw110 plays a role in the balance between the latent and lytic states of the virus. The mechanisms by which Vmw110 achieves these functions are poorly understood. Vmw110 migrates to discrete nuclear structures (ND10) which contain the cellular PML protein, and in consequence PML and other constituent proteins are dispersed. In addition, Vmw110 binds to a cellular protein of approximately 135 kDa, and its interactions with the 135 kDa protein and ND10 contribute to its ability to stimulate gene expression and viral lytic growth. In this report we identify the 135 kDa protein as a novel member of the ubiquitin-specific protease family. The protease is distributed in the nucleus in a micropunctate pattern with a limited number of larger discrete foci, some of which co-localize with PML in ND10. At early times of virus infection, the presence of Vmw110 increases the proportion of ND10 which contain the ubiquitin-specific protease. These results identify a novel, transitory component of ND10 and implicate a previously uncharacterized ubiquitin-dependent pathway in the control of viral gene expression.

Replacement of the herpes simplex virus type 1 Vmw175 DNA binding domain with its varicella-zoster virus counterpart results in a protein with novel regulatory properties that can support virus growth

The alphaherpesviruses encode major immediate early transactivator proteins that are essential for the expression of later classes of viral genes. We have previously shown that the extensive sequence similarity between the herpes simplex virus type 1 (HSV-1) and varicella-zoster virus (VZV) members of the family (proteins Vmw175 and VZV140k) extends to function, since a virus which expresses VZV140k in place of Vmw175 is able to grow, albeit at reduced efficiency. We have also shown that the DNA binding characteristics of the isolated DNA binding domains of Vmw175 and VZV140k are related but distinct. In order to assess whether the different DNA binding properties of the two proteins are responsible for the differences in their individual transcriptional regulatory functions, we constructed a plasmid and an HSV-1 virus in which the VZV140k DNA binding domain coding sequences replace those of Vmw175. The characteristics of the resultant hybrid protein in transfection assays and during virus infection suggest that the nature of the DNA binding domain plays a significant role in the transactivation and repression properties of the Vmw1 75 family of proteins.

Point mutations in the herpes simplex virus type 1 Vmw110 RING finger helix affect activation of gene expression, viral growth, and interaction with PML-containing nuclear structures

Herpes simplex virus type 1 immediate-early protein Vmw110 (also known as ICP0) has been implicated in the control of the balance between the lytic and latent states, but the precise mechanisms by which it exerts its effects are unknown. Vmw110 includes a characteristic zinc binding domain, termed the C3HC4 domain or RING finger, which is essential for its function. The solution structure of a related herpesvirus RING finger domain suggested that an amphipathic alpha helix might be an important functional component of the RING finger. In this paper, we show that the equivalent region of Vmw110 is important for virus growth in tissue culture and for the normal interaction of Vmw110 with nuclear structures which include the PML protein.

The equine herpesvirus 1 gene 63 RING finger protein partially complements Vmw110, its herpes simplex virus type 1 counterpart

All alpha herpesviruses of known DNA sequence have been found to encode a protein with similarities to immediate early protein Vmw110 (ICP0) of herpes simplex virus type 1 (HSV-1). The conserved portion of this family of proteins is a characteristic zinc binding module, known as a RING finger or C3HC4 domain. Examples of RING finger domains occur in many other proteins of diverse evolutionary origin and function. Recently, the solution structure of the equine herpesvirus 1 (EHV-1) RING finger protein, encoded by gene 63, has been solved. To investigate whether this structure could be considered to be a paradigm of herpesvirus RING domains, we have constructed a recombinant HSV-1 which expresses the EHV-1 gene 63 protein (EHVg63) in place of Vmw110. Comparison of the growth properties of the recombinant with those of wild-type and Vmw110-defective viruses indicates that EHVg63 is able to fulfil partially, but not completely, the roles of Vmw110 during virus growth in tissue culture.

Separation of sequence requirements for HSV-1 Vmw110 multimerisation and interaction with a 135-kDa cellular protein

Herpes simplex virus type 1 immediate-early polypeptide Vmw110 (ICP0) is a general transactivator of gene expression in transfection assays and is required for the fully efficient onset of viral lytic replication. It has also been implicated in the process of viral reactivation from latency. Its mechanism of action is unknown, but any involvement in latency requires interactions between viral and host factors. We have previously shown that Vmw110 binds to a 135-kDa cellular protein. In this paper we define a short region towards the C-terminal end of Vmw110 that is required for the 135-kDa protein interaction in virus-infected cells and in vitro. We also confirm that the C-terminal region of Vmw110 contains residues that are responsible for the multimerisation of the protein; these sequences are at least partially distinct from those involved in 135-kDa binding. Both multimerisation and 135-kDa protein interaction are required for full viral infectivity, and elimination of these functions affects the normal interactions between Vmw110 and cellular nuclear structures that contain the PML protein.

The cellular RING finger protein PML is not a functional counterpart of the herpes simplex virus type 1 RING finger protein Vmw110

Herpes simplex virus type 1 (HSV-1) immediate early protein Vmw110 (also known as ICP0) is required for the fully efficient expression of viral genes during onset of lytic growth and for normal reactivation from latency. Both Vmw110 and the cellular protein PML are members of the RING finger family of zinc binding domain proteins, a family which includes an increasing number of examples from a wide evolutionary range. The function of the RING finger domain is unknown, and the question arises whether the RING finger (like several other examples of conserved domains) fulfils similar functions in these diverse proteins. Another link between Vmw110 and PML is that at early times of HSV-1 infection Vmw110 migrates to distinct nuclear structures which contain the PML protein. In order to test the possibility that PML and Vmw110, or their RING finger domains, fulfill similar functions, we have constructed recombinant viruses that express either intact PML, or a chimeric Vmw110 protein which contains the PML RING finger in place of its own. The results indicate that the PML and Vmw110 RING fingers are not functionally interchangeable, and that PML is not a cellular functional counterpart of Vmw110.

Herpes simplex virus type 1 immediate-early protein Vmw110 binds strongly and specifically to a 135-kDa cellular protein

Herpes simplex virus type 1 encodes five immediate-early gene products, at least three of which are required for fully efficient viral gene expression. One of these three, Vmw110 (or ICPO), is a potent and nonspecific activator of gene expression in transfection assays. Viruses which fail to express functional Vmw110 have a cell-type and multiplicity-dependent defect in viral gene expression. In addition, Vmw110 has been implicated in the reactivation of latent virus in mouse and tissue culture model systems. In this report we show that Vmw110 can be isolated as a fast-sedimenting complex from infected cells and that this complex contains a cellular protein which is immune precipitated in association with Vmw110. This association can be reconstructed by adding purified Vmw110 to lysates of several different cell types. By using a GST fusion protein, we have found that the isolated C-terminal portion of Vmw110 can complex strongly and specifically with a similar cellular protein. The relevance of this observation to the roles of Vmw110 in latent and lytic virus infection is discussed.

The relative expression of human histone H2A genes is similar in different types of proliferating cells

To help elucidate the factors regulating the expression of histone multigene families in proliferating cells, we asked whether the relative expression of different members of such a family was dependent upon or independent of the type of proliferating cell. This question was examined by measuring the relative expression of seven members of the human histone H2A multigene family in four cell lines of diverse origin. Two previously uncharacterized members of the H2A gene family were found to be the most abundantly expressed of the seven in all four cell lines. One of these encodes an H2A.2 species containing methionine. The lines examined in the study were Jurkat (a lymphoma line), N-tera (a pluripotent embryonic carcinoma line), HeLa (originally isolated as a cervical carcinoma), and IMR90 (a normal embryonic fibroblastic line). The amount of each mRNA species was quantitated using oligonucleotides about 30 bases long complementary to the 5' or 3' untranslated regions. In each cell line, there was at least an eight-fold difference in the amount of the most and least highly expressed of the seven H2A mRNA species. In addition, there were up to five-fold differences among the cell lines in the amount of the H2A mRNA species as a fraction of total RNA. However, in contrast to those differences, the four cell lines were found to express the seven H2A mRNAs in similar relative amounts. These findings suggest that the relative expression of the individual members of a histone gene family is independent of the type of replicating cell.

Synthesis and DNA-sequence selectivity of a series of mono- and difunctional 9-aminoacridine nitrogen mustards

The aim of this work was to identify nitrogen mustards that would react selectively with DNA, particularly in G-rich regions. A series of mono- and difunctional nitrogen mustards was synthesized in which the (2-chloroethyl)amino functions were connected to the N9 of 9-aminoacridine by way of a spacer chain consisting of two to six methylene units. The length of the spacer chain connecting the alkylating and putative DNA-intercalating groups was found to affect the preference for the alkylation of different guanine-N7 positions in a DNA sequence. All of the compounds reacted preferentially at G's that are followed by G as do most other types of nitrogen mustards, but the degree of selectivity was greater. The compounds reacted at much lower concentrations than were required for comparable reaction by mechlorethamine (HN2), consistent with initial noncovalent binding to DNA prior to guanine-N7 alkylation. The degree of DNA-sequence selectivity increased as the spacer-chain length decreased below four methylene units. Most strikingly, long spacer compounds reacted strongly at 5'-GT-3' sequences, whereas this reaction was almost completely suppressed when the spacer length was reduced to two or three methylenes. Mono- and difunctional compounds of a given spacer length showed no consistent difference in DNA-sequence preference.

A novel arrangement of zinc-binding residues and secondary structure in the C3HC4 motif of an alpha herpes virus protein family

A highly conserved, cysteine-rich region plays a crucial role in the function of a family of regulatory proteins encoded by alpha herpes viruses. The so-called C3HC4 motif spans approximately 60 residues and has been predicted to bind zinc. This motif occurs in a number of other viral and cellular proteins, many of which appear to be involved in some aspect of the regulation of gene expression. We have cloned and expressed in bacteria a portion of immediate-early protein Vmw110 of herpes simplex virus type 1 that encompasses the C3HC4 motif, and the equivalent regions from the homologous proteins of varicella zoster virus and equine herpes virus type 1 (EHV-1). All three polypeptides were purified and found to bind zinc stably. None of the three interacted significantly with either DNA or RNA under our assay conditions. The EHV-1 domain yielded interpretable proton nuclear magnetic resonance spectra. Assignment of resonances and analysis of nuclear Overhauser effects revealed its secondary structure. Starting from the N terminus, this consists of an ordered but irregular loop, the first two strands of a triple-stranded antiparallel beta-sheet, two turns of an alpha-helix, a second irregular loop, and the third strand of the beta-sheet. It appears that, taking the cysteine and histidine residues in turn, cysteine residues I, II, IV and V co-ordinate one zinc atom while the histidine residue and cysteine residues III, VI and VII co-ordinate a second zinc atom. This arrangement of secondary structure differs from that found in other characterized zinc-containing proteins.

A truncated form of herpes simplex virus type 1 immediate-early protein Vmw110 is expressed in a cell type dependent manner

Herpes simplex virus type 1 (HSV-1) encodes five immediate-early (IE) genes, at least three of which are involved in the regulation of gene expression. Gene IE-1 is one of the few HSV-1 genes whose pre-mRNAs are spliced; the IE-1 pre-mRNA contains two introns, the second of which contains an in-frame stop codon which would terminate IE-1 translation if the intron were not excised. Previous work has shown that plasmids which have been constructed so as to express only the first two exons of Vmw110 can inhibit gene expression in transfection assays, whereas the normal intact protein is an activator of gene expression. In this paper we show that this predicted truncated Vmw110 protein is expressed during normal HSV-1 infection, and that it must be translated from IE-1 pre-mRNAs which retain the in-frame stop codon in the second intron. This truncated product is produced in amounts which depend upon the cell type infected. The possible consequences of these observations are discussed.