Measuring the density structure of an accretion hot spot.

Magnetospheric accretion models predict that matter from protoplanetary disks accretes onto stars via funnel flows, which follow stellar magnetic field lines and shock on the stellar surfaces1-3, leaving hot spots with density gradients4-6. Previous work has provided observational evidence of varying density in hot spots7, but these observations were not sensitive to the radial density distribution. Attempts have been made to measure this distribution using X-ray observations8-10; however, X-ray emission traces only a fraction of the hot spot11,12 and also coronal emission13,14. Here we report periodic ultraviolet and optical light curves of the accreting star GM Aurigae, which have a time lag of about one day between their peaks. The periodicity arises because the source of the ultraviolet and optical emission moves into and out of view as it rotates along with the star. The time lag indicates a difference in the spatial distribution of ultraviolet and optical brightness over the stellar surface. Within the framework of a magnetospheric accretion model, this finding indicates the presence of a radial density gradient in a hot spot on the stellar surface, because regions of the hot spot with different densities have different temperatures and therefore emit radiation at different wavelengths.

Follow-up of women with cervical adenocarcinoma in situ treated by conization: A single centre clinical experience.

OBJECTIVE: Hysterectomy has been the historical gold standard final step in the treatment algorithm of adenocarcinoma in situ (AIS) recommended by most North American colposcopy guidelines. AIS disproportionately affects young childbearing age women, therefore a fertility sparing treatment option is desirable. Our study examines the impact of conservative treatment of AIS with conization followed by serial surveillance. METHODS: A retrospective chart review was completed of patients treated for AIS from 2006 to 2020. Charts were identified by pathologic diagnosis of AIS on cervical and uterine specimens. Charts were excluded if AIS was not treated with conization, if AIS was not confirmed on initial conization specimen, or if invasive disease was found at initial conization. RESULTS: 121 patient charts were analyzed. Median age of patients at first conization and hysterectomy was 34.8 and 40.9, respectively. First conization was by Cold Knife Cone in 58% of patients, and by Loop Electrosurgical Excisional Procedure in 42% of patients. Median follow-up period in our study was 609 days. 5% of patients had recurrence, with only one patient who recurred as cancer. One case of recurrence had a positive initial conization margin. Median time to recurrence was 700 days. 47% of patients underwent eventual hysterectomy. Residual AIS was found in 23% of hysterectomy specimens. Adenocarcinoma was diagnosed on hysterectomy specimen in four patients. CONCLUSION: Our study demonstrates the oncologic safety of treating AIS with conization and serial surveillance. Routine hysterectomy completed as a part of the AIS treatment algorithm, as in current clinical guidelines, is unnecessary.

Dietary trehalose enhances virulence of epidemic Clostridium difficile.

Clostridium difficile disease has recently increased to become a dominant nosocomial pathogen in North America and Europe, although little is known about what has driven this emergence. Here we show that two epidemic ribotypes (RT027 and RT078) have acquired unique mechanisms to metabolize low concentrations of the disaccharide trehalose. RT027 strains contain a single point mutation in the trehalose repressor that increases the sensitivity of this ribotype to trehalose by more than 500-fold. Furthermore, dietary trehalose increases the virulence of a RT027 strain in a mouse model of infection. RT078 strains acquired a cluster of four genes involved in trehalose metabolism, including a PTS permease that is both necessary and sufficient for growth on low concentrations of trehalose. We propose that the implementation of trehalose as a food additive into the human diet, shortly before the emergence of these two epidemic lineages, helped select for their emergence and contributed to hypervirulence.

A new clinical sign to detect radiologically occult greater tuberosity fractures.

INTRODUCTION: Up to 59% of undisplaced greater tuberosity (GT) fractures are missed on initial evaluation. Timely diagnosis of these injuries can avoid undue morbidity, but a clinical sign to accurately identify them has not previously been described. Magnetic resonance imaging (MRI) remains the gold standard for their assessment but may not be routinely available, or difficult to organize urgently. We aimed to evaluate the diagnostic efficacy of a new clinical sign (the anterior bruise sign [ABS]), in diagnosing radiologically occult GT fractures. METHODS: Over a 4-year period, 59 patients who sustained a traumatic shoulder injury with no fracture on initial radiographs were referred to a specialist shoulder clinic within a week of their injury and enrolled in a prospective observational cohort study. At initial presentation, the presence of anterior arm bruising extending to the mid-diaphysis was recorded as a positive ABS. MRI assessment of the injured shoulder was performed in all patients at first follow-up. Presenting radiographs, 2-week radiographs, and MRI scans were reviewed by a musculoskeletal radiologist. The diagnostic value of a positive ABS was compared with 2-week radiographs, and other clinical tests. RESULTS: The mean age of the cohort was 58.5 (range 30-79) years, and 27 (45.8%) were female. The mean time from injury to first follow-up was 6.9 (standard deviation 2.4) days. MRI revealed that 25 of 59 patients (42.4%) had an undisplaced GT fracture. The overall accuracy of the ABS in identifying occult GT fractures was 98% (sensitivity = 100%, specificity = 97%, positive predictive value = 96%, negative predictive value = 100%, P < .001). In contrast, radiographs taken at 2 weeks postinjury were less accurate (71.2%) (P < .001), and other clinical assessments of cuff function had much lower accuracy. CONCLUSION: In patients presenting with a traumatic shoulder injury with normal radiographs, the ABS is a highly sensitive and specific clinical aid to identify patients with an occult GT fracture.

Effect of temperature on the dissolution of the lead (II) carbonate hydrocerussite for varying pH and dissolved inorganic carbon conditions.

The effect of temperature on the solubility of lead-bearing solid phases in water distribution systems for different water chemistry conditions remains unclear although lead concentrations are known to vary seasonally. The study objective is to explore the effect of temperature on the solubility of the lead(II) carbonate hydrocerussite under varying pH and DIC conditions. This is achieved through batch dissolution experiments conducted at multiple pHs (6-10) and DIC concentrations (20-200 mg CL-1) at temperatures ranging from 5 to 40 °C. A thermodynamic model was also applied to evaluate the model's ability to predict temperature effects on lead(II) carbonate solubility including solid phase transformations. In general, increasing temperature increased total dissolved lead at high pHs and the effect of temperature was greater for high DIC conditions, particularly for pH > 8. Temperature also influenced the pH at which the dominant lead(II) solid phase switched from hydrocerussite to cerussite (occurred between pH 7.25 to 10). Finally, the model was able to capture the overall trends observed despite thermodynamic data limitations. While this study focuses on a simple lead solid-aqueous system, findings provide important insights regarding the way in which temperature and water chemistry interact to affect lead concentrations.

Impact of the COVID-19 pandemic on a post-mortem CT service for adult non-suspicious death.

Due to the COVID-19 pandemic, the post-mortem computed tomography (PMCT) service was expanded from three to seven cases per day to help mortuary services and avoid invasive autopsy. Additional targeted angiography and pulmonary ventilation procedures were stopped and triage rules relaxed to allow more indications to be scanned, including those requiring toxicology. A service evaluation was performed for the first 3-months of the COVID-19 pandemic compared to the equivalent period the previous year to study the impact of these changes. It was found that, despite the increase in deaths regionally, coronial referrals remained about 100 per month, a reduction in referral rate. The number undergoing PMCT rose from 28% to 74% of cases. Turnaround time remained the same. For cases triaged to PMCT, the need for subsequent autopsy increased from 7.9% to 15.8%. No significant changes were seen in diagnosis rates, including cardiac or respiratory. There was an increase in patients with coronary death without severe coronary calcification who underwent autopsy after PMCT. These may have been diagnosed by targeted coronary angiography. Fifty-three cases requiring toxicology/biochemistry had PMCT, with 38 having PMCT only. In 8/11 (72.7%) cases with normal PMCT and toxicology as the key diagnostic test, autopsy was performed prior to results. This suggests the pathology team were reluctant to risk an "unascertained" outcome. This study shows that it is possible to increase PMCT services by widening referral criteria and by limiting the use of enhanced imaging techniques, without significantly changing diagnosis rates of key diseases; however, selectively restarting targeted angiography may help avoid autopsy in some cases.

Impact of changing from autopsy to post-mortem CT in an entire HM Coroner region due to a shortage of available pathologists.

A significant problem facing routine medicolegal coroner-referred autopsies is a shortfall of pathologists prepared to perform them. This was particularly acute in Lancashire, where the coroner decided to initiate a service that relied on post-mortem computed tomography (PMCT). This involved training anatomical pathology technologists (APTs) to perform external examinations, radiographers to perform scans, and radiologists to interpret them. The service started in 2018 and now examines over 1,500 cases per year. This study outlines the PMCT process using NHS staff, with CT equipment and logistics managed by the commercial sector. It compares the demographics and outcomes of PM investigations for two 6-month periods: the autopsy service prior to 2018, and then the PMCT service. These data were then compared with previous UK PMCT data. Referrals for adult non-suspicious deaths were made in 913 cases of which 793 (87%) had PMCT between 01/10/2018 and 31/03/2019. Fifty-six cases had autopsy after PMCT, so 81% of cases potentially avoided autopsy. The PMCT service did not delay release of bodies to the next-of-kin. Comparing the cause of death given shows no difference in the proportions of natural and unnatural deaths. There was an increase in diagnosis of coronary artery disease for PMCT, with less respiratory diagnoses, a feature not previously demonstrated. These data suggest PMCT is a practical solution for potentially failing autopsy services. By necessity, this involves changes in diagnoses, as PMCT and autopsy have different strengths and weakness, but the ability to pick up unnatural death appears unaffected.

Hospital re-admission after critical care survival: a systematic review and meta-analysis.

Survivors of critical illness frequently require increased healthcare resources after hospital discharge. We undertook a systematic review and meta-analysis to assess hospital re-admission rates following critical care admission and to explore potential re-admission risk factors. We searched the MEDLINE, Embase and CINAHL databases on 05 March 2020. Our search strategy incorporated controlled vocabulary and text words for hospital re-admission and critical illness, limited to the English language. Two reviewers independently applied eligibility criteria and assessed quality using the Newcastle Ottawa Score checklist and extracted data. The primary outcome was acute hospital re-admission in the year after critical care discharge. Of the 8851 studies screened, 87 met inclusion criteria and 41 were used within the meta-analysis. The analysis incorporated data from 3,897,597 patients and 741,664 re-admission episodes. Pooled estimates for hospital re-admission after critical illness were 16.9% (95%CI: 13.3-21.2%) at 30 days; 31.0% (95%CI: 24.3-38.6%) at 90 days; 29.6% (95%CI: 24.5-35.2%) at six months; and 53.3% (95%CI: 44.4-62.0%) at 12 months. Significant heterogeneity was observed across included studies. Three risk factors were associated with excess acute care rehospitalisation one year after discharge: the presence of comorbidities; events during initial hospitalisation (e.g. the presence of delirium and duration of mechanical ventilation); and subsequent infection after hospital discharge. Hospital re-admission is common in survivors of critical illness. Careful attention to the management of pre-existing comorbidities during transitions of care may help reduce healthcare utilisation after critical care discharge. Future research should determine if targeted interventions for at-risk critical care survivors can reduce the risk of subsequent rehospitalisation.

Delayed acromioclavicular joint reconstruction using a modern suspensory device does not increase the risk of fixation failure or major complications.

BACKGROUND: Management of displaced acromioclavicular joint (ACJ) injuries remains contentious. It is unclear if delayed vs. acute reconstruction has an increased risk of fixation failure and complications. The primary aim of this study was to compare complications of early vs. delayed reconstruction. The secondary aim was to determine modes of failure of ACJ reconstruction requiring revision surgery. METHODS: A retrospective study was performed on all patients who underwent operative reconstruction of ACJ injuries over a 10-year period (Rockwood III-V) using suspensory devices with or without hamstring allograft. Reconstruction was classed as early (<12 weeks from injury) or delayed (≥12 weeks). Patient demographics, fixation method, and postoperative complications were noted, with 1-year follow-up a minimum requirement for inclusion. Patient-reported outcomes with the Disabilities of the Arm, Shoulder, and Hand score and EuroQol-5 Dimension were undertaken. Fixation failure was defined as loss of reduction requiring revision surgery. RESULTS: A total of 104 patients were analyzed (n = 59 early and n = 45 delayed). The mean age was 42.0 (standard deviation: 11.2; 17-70 years); 84.6% were male and 15.4% were smokers. No difference was observed between fixation failure (P = .39) or deep infection (P = .13) with regard to acute vs. delayed reconstruction. No patient demographic or timing of surgery was predictive of fixation failure on regression modeling. Overall, 11 patients underwent revision surgery for loss of reduction and implant failure (n = 5 suture fatigue, n = 2 endobutton escape, n = 2 coracoid stress fracture, and n = 2 deep infection). The EuroQol-5 Dimension (P = .084) and Disabilities of the Arm, Shoulder, and Hand score (P = .062) were comparable for early and delayed groups respectively and below the minimal clinically important difference. CONCLUSION: This study found that delayed surgical management of ACJ injuries using a modern device has comparable functional outcomes and is not associated with a higher incidence of fixation failure or major complications.

Novel homozygous variant in BMP1 associated with a rare osteogenesis imperfecta phenotype.

Osteogenesis imperfecta (OI) is characterized by bone fragility and increased fracture susceptibility. BMP1 variants have been reported in the rare OI type XIII, specifically referred to herein as BMP1-associated autosomal recessive (AR) OI. We report the clinical presentation and diagnostic evaluation of a patient found to have a novel homozygous variant in BMP1. We also provide an overview of reported BMP1 variants to date, with discussion focusing on the use of bisphosphonate therapy in these patients. A 7-year-old male with speech and motor delay sustained five bilateral tibial fractures with minimal trauma since age 2.5 years. At age 6, he developed severe back pain after a fall. Diffuse spinal osteopenia and multiple vertebral compression fractures (VCF) at T9, L1, L3, and L5 were identified. Total hip BMD was generous (adjusted Z-score* = 1.76), and femoral neck BMD was high (adjusted Z-score* = 2.67). VCFs precluded assessment of lumbar spine BMD. Genetic analysis identified a homozygous missense variant in exon 4 of BMP1 (c.C505T; p.Arg169Cys). Unlike most forms of OI, patients with BMP1-associated AR OI may have normal or paradoxically increased BMD, making BMD and fracture risk correlation difficult. While bisphosphonates (BP) may help reduce recurrent fractures and provide symptomatic relief, the broad phenotypic spectrum and underlying bone pathology, often in the setting of increased BMD, complicate management. HR-pQCT assessment of bone microarchitecture and quality may aid in the decision of BP therapy and subsequent monitoring. Evidence is limited with respect to the effectiveness of BP in this rare form of OI. *Z-score was adjusted for height Z-score.

Thermodynamic basis of the α-helix and DNA duplex.

Analysis of calorimetric and crystallographic information shows that the α-helix is maintained not only by the hydrogen bonds between its polar peptide groups, as originally supposed, but also by van der Waals interactions between tightly packed apolar groups in the interior of the helix. These apolar contacts are responsible for about 60% of the forces stabilizing the folded conformation of the α-helix and their exposure to water on unfolding results in the observed heat capacity increment, i.e. the temperature dependence of the melting enthalpy. The folding process is also favoured by an entropy increase resulting from the release of water from the peptide groups. A similar situation holds for the DNA double helix: calorimetry shows that the hydrogen bonding between conjugate base pairs provides a purely entropic contribution of about 40% to the Gibbs energy while the enthalpic van der Waals interactions between the tightly packed apolar parts of the base pairs provide the remaining 60%. Despite very different structures, the thermodynamic basis of α-helix and B-form duplex stability are strikingly similar. The general conclusion follows that the stability of protein folds is primarily dependent on internal atomic close contacts rather than the hydrogen bonds they contain.

Potential re-use of sewage sludge as a raw material in the production of eco-friendly bricks.

Wastewater (sewage) treatment plants generate a high volume of sludge that, although it is classified as class II-A (not inert) non-hazardous waste, is commonly disposed of in sanitary landfills. Hence the environmental urge to assess its valorization possibilities. The present study describes the use of a sewage sludge as raw material in the production of red ceramic bricks by extrusion, focusing on the technological changes brought about by the presence of the sludge during the plastic forming process, in terms of the plasticity of the mixture and its subsequent extrudability. To quantitatively identify the best moisture conditions for the extrusion of high-quality products, shear strain amplitude sweep (torsional) tests were conducted on green (moist) prismatic samples produced with different moisture and sludge contents. For sewage sludge contents up to 10 wt%, the optimal moisture content was identified at 31-33 wt%. Higher water demand was identified for 15 wt% of sludge, for which optimal extrusion results required 35 wt% moisture. The total linear shrinkage after drying and firing, as well as the water absorption, were within the limits required for ceramic bricks for all the sludge contents. The results for compressive strength of the fired bricks also demonstrate that the incorporation of up to 15 wt% sewage sludge into the clay mixture is highly feasible for the production of extruded ceramic bricks.

Cellular and proteomic events associated with the localized formation of smut-gall during Zizania latifolia-Ustilago esculenta interaction.

The perennial wild rice Zizania latifolia is confined in the swampy habitat and wetland of the Indo-Burma biodiversity hotspot of India and infection by the biotrophic fungus Ustilago esculenta is hallmarked by swellings that develop to form localized smut-gall at the topmost internodal region. The cellular and proteomic events involved in the non-systemic colonization of Z. latifolia by U. esculenta leading to smut-gall formation is poorly understood. Proteins were extracted from the smut-gall region at the topmost internodal region below the apical meristematic tissue from the infected and uninfected parts of Z. latifolia. By combining transmission electron microscopy (TEM) and fluorescent microscopy (FM), we showed that U. esculenta hyphal morphological transitions and movement occurred both intercellularly and intracellularly while sporulation occurred intracellularly in selective cells. Following proteome profiling using two dimensional SDS-PAGE at different phenological phases of smut-gall development and U. esculenta infection, differentially expressed proteins bands and their relative abundance were detected and subjected to liquid chromatography-tandem mass spectrometric (LC-MS/MS) analysis. Importantly, the fungus explores at least 7 metabolic pathways and 5 major biological processes to subdue the host defense and thrive successfully on Z. latifolia. The fungus U. esculenta produces proteases and energy acquisition proteins those enhance it's defensive and survival mode in the host. The identified differentially regulated proteins shed-light into why inflorescence is being replaced by bulbous smut-gall at late stages of the disease, as well as the development of resistance in some Z. latifolia plants against U. esculenta infection.

A disclosure gel for visual detection of live Bacillus anthracis spores.

AIMS: To develop a gel formulation to trigger a visual signal for rapid disclosure of the location and extent of surface contamination with viable Bacillus anthracis spores. METHODS AND RESULTS: Methylumbelliferyl-α-d-glucopyranoside was combined with hyaluronic acid to produce a gel that could be applied to a surface as a coating. It remained hydrated for a sufficient time for α-glucosidase activity present in intact B. anthracis spores to cleave the substrate and release the fluorescent product, methylumbelliferone. The presence of B. anthracis spores could be disclosed at 5 × 104 CFU per reaction test well (0·32 cm2 ) both visually and using fluorescence detection equipment. CONCLUSIONS: The disclosure gel provides a rapid, visual response to the presence of B. anthracis spores on a surface. SIGNIFICANCE AND IMPACT OF THE STUDY: The disclosure gel demonstrates the first steps towards the development of a formulation that can provide nonspecialist users with a visual alert to the presence of B. anthracis spores on a surface. It is envisioned that such a formulation would be beneficial in scenarios where exposure to spore release is a risk, and could be used in the initial assessment of equipment to aid prioritization and localized execution of a decontamination strategy.

Post-mortem CT: is coronary angiography required in the presence of a high coronary artery calcium score?

AIM: To test whether a high coronary artery score predicts that the subsequent post-mortem computed tomography (PMCT) with angiography (PMCTA) will diagnose significant coronary artery disease (CAD); to test the diagnostic impact of assuming there is significant CAD based on a high coronary artery calcium (CAC) score alone; and (3) to test whether the clinical CAC score threshold (400) is the most accurate to make this prediction. MATERIALS AND METHODS: CAC scoring and PMCTA were performed in cases of adult sudden natural death. Angiography was reviewed to determine if there was sufficient CAD to give as the cause of death. Data were analysed to test whether high calcium score predicts significant CAD. RESULTS: PMCTA with CAC score was successful in 100/104 PMCT examinations and in 87/100 angiography examinations (87%). Forty-six cases (46%) had a CAC score of >400, the clinical level of severe disease. CAD was given as the cause of death in 31 (67%) of these cases. Angiography was successful in 39 of these cases (84.7%) and showed severe CAD in all but one (97%). Twenty-five (25%) cases were diagnosed with a CAD death without a high CAC score. CONCLUSION: Although CAC score can neither diagnose nor exclude death due to CAD, the addition of angiography adds little diagnostic information to a high CAC score. If PMCT investigation is to exclude trauma and provide a medical cause of death on the "balance of probabilities", angiography is not required when the calcium score >400. This could reduce the number of patients requiring angiography by almost 50%.

Biotechnological application of endophytic filamentous bipolaris and curvularia: a review on bioeconomy impact.

The filamentous Bipolaris and Curvularia genera consist of species known to cause severe diseases in plants and animals amounting to an estimated annual loss of USD $10 billion worldwide. Despite the harmful effect of Bipolaris and Curvularia species, scarce attention is paid on beneficial areas where the fungi are used in industrial processes to generate biotechnological products. Catalytic potential of Bipolaris and Curvularia species in the production of biodiesel, bioflucculant, biosorbent, and mycoherbicide are promising for the bioeconomy. It is herein demonstrated that knowledge-based application of some endophytic Bipolaris and Curvularia species are indispensable vectors of sustainable economic development. In the twenty-first century, India, China, and the USA have taken progress in the biotechnological application of these fungi to generate wealth. As such, some Bipolaris and Curvularia species significantly impact on global crop improvement, act as catalyst in batch-reactors for biosynthesis of industrial enzymes and medicines, bioengineer of green-nanoparticle, agent of biofertilizer, bioremediation and bio-hydrometallurgy. For the first time, this study discusses the current advances in biotechnological application of Bipolaris and Curvularia species and provide new insights into the prospects of optimizing their bioengineering potential for developing bioeconomy.

Bone marrow failure and extramedullary hematopoiesis in McCune-Albright syndrome.

In fibrous dysplasia/McCune-Albright syndrome (FD/MAS), bone and bone marrow are, to varying degrees, replaced by fibro-osseous tissue typically devoid of hematopoietic marrow. Despite the extensive marrow replacement in severely affected patients, bone marrow failure is not commonly associated with FD/MAS. We present a 14-year-old girl with FD/MAS, who developed pancytopenia and extramedullary hematopoiesis (EMH) with no identified cause, in the setting of iatrogenic thyrotoxicosis and hyperparathyroidism. Pancytopenia, requiring monthly blood transfusions, persisted despite multiple strategies to correct these endocrinopathies. Due to worsening painful splenomegaly, likely as a result of sequestration, splenectomy was performed. Following splenectomy, pancytopenia resolved and patient has since been transfusion-independent. We report the first detailed case of bone marrow failure and EMH in FD/MAS. The etiology of marrow failure is likely multifactorial and related to the loss of marrow reserve due to extensive polyostotic FD, exacerbated by iatrogenic thyrotoxicosis and hyperparathyroidism. Mini Abstract: A patient with fibrous dysplasia developed bone marrow failure and extramedullary hematopoiesis. The etiology likely involved loss of hematopoetic marrow space and uncontrolled endocrinopathies. Splenectomy was therapeutic.

Differential Impact of Index Stroke on Dementia Risk in African-Americans Compared to Whites.

OBJECTIVE: To compare whites and African-Americans in terms of dementia risk following index stroke. METHODS: The data consisted of billing and International Classification of Diseases, Ninth Revision diagnosis codes from the South Carolina Revenue and Fiscal Affairs office on all hospital discharges within the state between 2000 and 2012. The sample consisted of 68,758 individuals with a diagnosis of ischemic stroke prior to 2010 (49,262 white [71.65%] and 19,496 African-Americans [28.35%]). We identified individuals in the dataset who were subsequently diagnosed with any of 5 categories of dementia and evaluated time to dementia diagnosis in Cox Proportional Hazards models. We plotted cumulative hazard curves to illustrate the effect of race on dementia risk after controlling for age, sex, and occurrence of intervening stroke. RESULTS: Age at index stroke was significantly different between the 2 groups, with African-Americans being younger on average (70.0 [SD 12.5] in whites versus 64.5 [SD 14.1] in African-Americans, P < .0001). Adjusted hazard ratios revealed that African-American race increased risk for all 5 categories of dementia following incident stroke, ranging from 1.37 for AD to 1.95 for vascular dementia. Age, female sex, and intervening stroke likewise increased risk for dementia. CONCLUSIONS: African-Americans are at higher risk for dementia than whites within 5 years of ischemic stroke, regardless of dementia subtype. Incident strokes may have a greater likelihood of precipitating dementia in African-Americans due to higher prevalence of nonstroke cerebrovascular disease or other metabolic or vascular factors that contribute to cognitive impairment.

Utilisation of preconception care services and determinants of poor uptake among a cohort of women in Abakaliki Southeast Nigeria.

Preconception care (PCC) is a preventive strategy for maternal and perinatal morbidity and mortality. This study aimed to assess the level of awareness and utilisation of PCC services. A descriptive cross-sectional survey was conducted at a teaching hospital. Interviewer-administered questionnaires were used to extract information. A total of 450 participants responded; 44.2% (190/450) were aware, 31.7% (143/450) had good knowledge, while only 10.3% (46/450) received PCC. Health care providers were the main source of information (77.9%). There was statistically significant correlation between awareness and participants' level of education (p < .001) and residence (p < .001), as well as between utilisation and education (p < .001), and information from doctors (p < .001). There was a low level of awareness and poor utilisation of PCC, underpinning the need to scale up health education, establishment of functional PCC clinics and formulation of evidence-based guidelines to improve uptake and pregnancy outcome. Impact statement What is already known on the subject of the paper? PCC has been known in high-income countries as a prevention-based strategy, which aims at improving obstetric outcomes. However, the level of utilisation in low-income countries like Nigeria is either unknown or far too low. What do this study add? This work has provided local data on PCC; clearly indicating that the awareness and utilisation of PCC services in Abakaliki, Nigeria is very low when compared with other regions of the world, and this was influenced by the socio-demographic factors - particularly education and place of residence (for awareness), and level of education and information from health care providers (for utilisation), thus suggesting that enlightenment and improvement in social infrastructures could improve awareness, access and utilisation of PCC. What are the implications for clinical practice and/or further research? The implications of these findings in low resource settings like ours will include introducing interventions to scaling up health education, universal establishment of functional PCC units and formulation of evidence-based guidelines aimed at improving the uptake of PCC and pregnancy outcome. Further research will also be needed in future to assess the impact of such interventions and how to sustain potential benefits.

Linker histones: History and current perspectives.

Although the overall structure of the fifth histone (linker histone, H1) is understood, its location on the nucleosome is only partially defined. Whilst it is clear that H1 helps condense the chromatin fibre, precisely how this is achieved remains to be determined. H1 is not a general gene repressor in that although it must be displaced from transcription start sites for activity to occur, there is only partial loss along the body of genes. How the deposition and removal of H1 occurs in particular need of further study. Linker histones are highly abundant nuclear proteins about which we know too little.