Species coexistence by wide constant size spacing.

We consider the distribution of fruit pigeons of the genera Ptilinopus and Ducula on the island of New Guinea. Of the 21 species, between six and eight coexist inside humid lowland forests. We conducted or analyzed 31 surveys at 16 different sites, resurveying some sites in different years. The species coexisting at any single site in a single year are a highly nonrandom selection of the species to which that site is geographically accessible. Their sizes are both much more widely spread and more uniformly spaced than in random sets of species drawn from the locally available species pool. We also present a detailed case study of a highly mobile species that has been recorded on every ornithologically explored island in the West Papuan island group west of New Guinea. That species' rareness on just three well-surveyed islands within the group cannot be due to an inability to reach them. Instead, its local status decreases from abundant resident to rare vagrant in parallel with increasing weight proximity of the other resident species.

How Trust in Cancer Information Has Changed in the Era of COVID-19: Patterns by Race and Ethnicity.

COVID-19 emerged during an era of heightened attention to systemic racism and the spread of misinformation. This context may have impacted public trust in health information about chronic diseases like cancer. Here, we examine data from the 2018 and 2020 Health Information National Trends Survey (N = 7,369) to describe how trust in cancer information from government health agencies, doctors, family and friends, charitable organizations, and religious organizations changed after COVID-19 became a pandemic, and whether that change varied by race/ethnicity. Statistical methods included chi-square tests and multiple logistic regression modeling. Overall, the proportion of respondents who reported a high degree of trust in cancer information from doctors increased (73.65% vs. 77.34%, p = .04). Trends for trust in information from government health agencies and family and friends varied significantly by race/ethnicity, with substantial declines observed among non-Hispanic Blacks (NHB) only. The odds of reporting a high degree of trust in cancer information from government health agencies and friends and family decreased by 53% (OR = 0.47, 95% CI = 0.24-0.93) and 73% (OR = 0.27, 95% CI = 0.09-0.82), respectively, among NHB, but were stable for other groups. Future studies should monitor whether recent declines in trust among NHB persist and unfavorably impact participation in preventive care.

Inequalities in life expectancy in Australia according to education level: a whole-of-population record linkage study.

BACKGROUND: Life expectancy in Australia is amongst the highest globally, but national estimates mask within-country inequalities. To monitor socioeconomic inequalities in health, many high-income countries routinely report life expectancy by education level. However in Australia, education-related gaps in life expectancy are not routinely reported because, until recently, the data required to produce these estimates have not been available. Using newly linked, whole-of-population data, we estimated education-related inequalities in adult life expectancy in Australia. METHODS: Using data from 2016 Australian Census linked to 2016-17 Death Registrations, we estimated age-sex-education-specific mortality rates and used standard life table methodology to calculate life expectancy. For men and women separately, we estimated absolute (in years) and relative (ratios) differences in life expectancy at ages 25, 45, 65 and 85 years according to education level (measured in five categories, from university qualification [highest] to no formal qualifications [lowest]). RESULTS: Data came from 14,565,910 Australian residents aged 25 years and older. At each age, those with lower levels of education had lower life expectancies. For men, the gap (highest vs. lowest level of education) was 9.1 (95 %CI: 8.8, 9.4) years at age 25, 7.3 (7.1, 7.5) years at age 45, 4.9 (4.7, 5.1) years at age 65 and 1.9 (1.8, 2.1) years at age 85. For women, the gap was 5.5 (5.1, 5.9) years at age 25, 4.7 (4.4, 5.0) years at age 45, 3.3 (3.1, 3.5) years at 65 and 1.6 (1.4, 1.8) years at age 85. Relative differences (comparing highest education level with each of the other levels) were larger for men than women and increased with age, but overall, revealed a 10-25 % reduction in life expectancy for those with the lowest compared to the highest education level. CONCLUSIONS: Education-related inequalities in life expectancy from age 25 years in Australia are substantial, particularly for men. Those with the lowest education level have a life expectancy equivalent to the national average 15-20 years ago. These vast gaps indicate large potential for further gains in life expectancy at the national level and continuing opportunities to improve health equity.

Painless neutropenic enterocolitis in a patient undergoing chemotherapy.

CASE DESCRIPTION: A 60-year-old man developed painless neutropenic enterocolitis after induction chemotherapy for newly diagnosed acute myelogenous leukemia. The patient had recurrent fever while neutropenic, without experiencing abdominal pain or tenderness on physical examination. His diagnosis was delayed by the fact that he had no localizing symptoms. DISCUSSION: Neutropenic enterocolitis is a common complication, generally occurring in patients who are severely neutropenic; the condition presents with fever and abdominal pain. No cases of painless neutropenic enterocolitis have yet been reported. Review of the literature shows that patients can develop this condition in the absence of fever and, sometimes, neutropenia. Furthermore, few comprehensive studies or reviews have investigated the utility of computed tomography imaging in identifying a source for abdominal pain in neutropenic patients with fever. SUMMARY: Many potential causes of febrile neutropenia should be considered in chemotherapy patients.

Does the Presence of Scrapie Affect the Ability of Current Statutory Discriminatory Tests To Detect the Presence of Bovine Spongiform Encephalopathy?

Current European Commission (EC) surveillance regulations require discriminatory testing of all transmissible spongiform encephalopathy (TSE)-positive small ruminant (SR) samples in order to classify them as bovine spongiform encephalopathy (BSE) or non-BSE. This requires a range of tests, including characterization by bioassay in mouse models. Since 2005, naturally occurring BSE has been identified in two goats. It has also been demonstrated that more than one distinct TSE strain can coinfect a single animal in natural field situations. This study assesses the ability of the statutory methods as listed in the regulation to identify BSE in a blinded series of brain samples, in which ovine BSE and distinct isolates of scrapie are mixed at various ratios ranging from 99% to 1%. Additionally, these current statutory tests were compared with a new in vitro discriminatory method, which uses serial protein misfolding cyclic amplification (sPMCA). Western blotting consistently detected 50% BSE within a mixture, but at higher dilutions it had variable success. The enzyme-linked immunosorbent assay (ELISA) method consistently detected BSE only when it was present as 99% of the mixture, with variable success at higher dilutions. Bioassay and sPMCA reported BSE in all samples where it was present, down to 1%. sPMCA also consistently detected the presence of BSE in mixtures at 0.1%. While bioassay is the only validated method that allows comprehensive phenotypic characterization of an unknown TSE isolate, the sPMCA assay appears to offer a fast and cost-effective alternative for the screening of unknown isolates when the purpose of the investigation was solely to determine the presence or absence of BSE.

Incidence of childhood cancer in Kingston and St Andrew, Jamaica, 1983-2002.

OBJECTIVES: There have been several modifications to the classification of childhood cancers since the first report (1968-1981) specific to the Jamaican paediatric population was published in 1988. This paper reports on paediatric cancer incidence in Kingston and St Andrew, Jamaica, for the 20-year period 1983-2002 based on these modifications. METHODS: All cases of cancer diagnosed in children (0-14 years), between 1983 and 2002 were extracted from the Jamaica Cancer Registry archives and classified using the International Classification of Childhood Cancer, third edition. Incidence figures were calculated as per the International Agency for Research on Cancer (IARC) reporting format for childhood cancer. RESULTS: There were 272 cases (133 males, 139 females) of childhood cancer identified in the 20-year period. The overall age standardized rate (ASR) was 69.4 per million; that for males was 67.8 per million, and for females, 70.9 per million. The three most common malignancies overall were leukaemia (21.3%), lymphoma (15.8%) and brain and spinal neoplasms (14.0%). In males, the highest ASRs were seen for leukaemia (14.8 per million), lymphoma (12.7 per million), and brain and spinal neoplasms (8.2 per million), and in females, leukaemia (14.4 per million), nephroblastoma (11.3 per million), and brain and spinal neoplasms (10.6 per million). CONCLUSIONS: The rankings of the most common childhood malignancies in Jamaica (leukaemia, brain and spinal neoplasms and lymphomas) have shown few changes since the last review. However, there are differences in frequency and gender distribution of nephroblastoma and brain and spinal neoplasms.

Perinatal autopsy rates at the University Hospital of the West Indies: 2002-2008.

OBJECTIVES: High perinatal autopsy rates are necessary for institutional management protocols and national policy-making. This study reviews perinatal autopsy rates and factors affecting these rates at the University Hospital of the West Indies. METHOD: All perinatal deaths (stillborn infants > or = 24 weeks gestation or 500 g; early neonatal deaths ie 0-7 days old) at the University Hospital of the West Indies, between January 2002 and December 2008, were reviewed retrospectively, using the annual perinatal audit records. The annual autopsy rates were calculated and the reasons why autopsies were not done examined. RESULTS: The average stillbirth (SB) autopsy rate was 59.6% (range 51.9 - 76.7%), while that for early neonatal deaths (ENDs) was 47.9% (range 34.4 - 63.2), with an overall average perinatal autopsy rate of 54.0% (range 42.2 - 62.2). Autopsies were requested in 79.3% and 51.7% of SBs and ENDs, respectively. Of those requested, 81.7% were done (75.2% stillbirths; 92.5% ENDs). In the ENDs, failure to request an autopsy was predominantly noted in premature infants weighing < 1000 g (75.2% of those not requested). In stillbirths, the reasons for failure to request were largely unknown with failure to gain permission accounting for only 20.3% of these cases. CONCLUSIONS: The average annual perinatal autopsy rate at the University Hospital of the West Indies between 2002 and 2008 was 54.0%. This is below the internationally recommended rate of 75%. Failure to request an autopsy was the most significant factor contributing to this. The reasons for this are not entirely clear and require further study.

Chronic fatigue syndrome, the immune system and viral infection.

The chronic fatigue syndrome (CFS), as defined by recent criteria, is a heterogeneous disorder with a common set of symptoms that often either follows a viral infection or a period of stress. Despite many years of intense investigation there is little consensus on the presence, nature and degree of immune dysfunction in this condition. However, slightly increased parameters of inflammation and pro-inflammatory cytokines such as interleukin (IL) 1, IL6 and tumour necrosis factor (TNF) α are likely present. Additionally, impaired natural killer cell function appears evident. Alterations in T cell numbers have been described by some and not others. While the prevalence of positive serology for the common herpes viruses appears no different from healthy controls, there is some evidence of viral persistence and inadequate containment of viral replication. The ability of certain herpes viruses to impair the development of T cell memory may explain this viral persistence and the continuation of symptoms. New therapies based on this understanding are more likely to produce benefit than current methods.

Enhanced anti-HIV functional activity associated with Gag-specific CD8 T-cell responses.

Effective HIV-specific T-cell immunity requires the ability to inhibit virus replication in the infected host, but the functional characteristics of cells able to mediate this effect are not well defined. Since Gag-specific CD8 T cells have repeatedly been associated with lower viremia, we examined the influence of Gag specificity on the ability of unstimulated CD8 T cells from chronically infected persons to inhibit virus replication in autologous CD4 T cells. Persons with broad (>or=6; n = 13) or narrow (

Screening for acute HIV infection in South Africa: finding acute and chronic disease.

BACKGROUND: The yield of screening for acute HIV infection among general medical patients in resource-scarce settings remains unclear. Our objective was to evaluate the strategy of using pooled HIV plasma RNA to diagnose acute HIV infection in patients with negative or discordant rapid HIV antibody tests in Durban, South Africa. METHODS: We prospectively enrolled patients with negative or discordant rapid HIV antibody tests from a routine HIV screening programme in an out-patient department in Durban with an HIV prevalence of 48%. Study participants underwent venipuncture for pooled qualitative HIV RNA, and, if this was positive, quantitative RNA, enzyme immunoassay and Western blot (WB). Patients with negative or indeterminate WB and positive quantitative HIV RNA were considered acutely infected. Those with chronic infection (positive RNA and WB) despite negative or discordant rapid HIV tests were considered to have had false negative rapid antibody tests. RESULTS: Nine hundred and ninety-four participants were enrolled with either negative (n=976) or discordant (n=18) rapid test results. Eleven [1.1%; 95% confidence interval (CI) 0.6-2.0%] had acute HIV infection, and an additional 20 (2.0%; 95% CI 1.3-3.1%) had chronic HIV infection (false negative rapid test). CONCLUSIONS: One per cent of out-patients with negative or discordant rapid HIV tests in Durban, South Africa had acute HIV infection readily detectable through pooled serum HIV RNA screening. Pooled RNA testing also identified an additional 2% of patients with chronic HIV infection. HIV RNA screening has the potential to identify both acute and chronic HIV infections that are otherwise missed by standard HIV testing algorithms.

Autumn destabilization of deep porewater CO2 store in a northern peatland driven by turbulent diffusion.

The deep porewater of northern peatlands stores large amounts of carbon dioxide (CO2). This store is viewed as a stable feature in the peatland CO2 cycle. Here, we report large and rapid fluctuations in deep porewater CO2 concentration recurring every autumn over four consecutive years in a boreal peatland. Estimates of the vertical diffusion of heat indicate that CO2 diffusion occurs at the turbulent rather than molecular rate. The weakening of porewater thermal stratification in autumn likely increases turbulent diffusion, thus fostering a rapid diffusion of deeper porewater CO2 towards the surface where net losses occur. This phenomenon periodically decreases the peat porewater CO2 store by between 29 and 90 g C m-2 throughout autumn, which is comparable to the peatland's annual C-sink. Our results establish the need to consider the role of turbulent diffusion in regularly destabilizing the CO2 store in peat porewater.

Regulation of area identity in the mammalian neocortex by Emx2 and Pax6.

The contribution of extrinsic and genetic mechanisms in determining areas of the mammalian neocortex has been a contested issue. This study analyzes the roles of the regulatory genes Emx2 and Pax6, which are expressed in opposing gradients in the neocortical ventricular zone, in specifying areas. Changes in the patterning of molecular markers and area-specific connections between the cortex and thalamus suggest that arealization of the neocortex is disproportionately altered in Emx2 and Pax6 mutant mice in opposing manners predicted from their countergradients of expression: rostral areas expand and caudal areas contract in Emx2 mutants, whereas the opposite effect is seen in Pax6 mutants. These findings suggest that Emx2 and Pax6 cooperate to regulate arealization of the neocortex and to confer area identity to cortical cells.

The use of MTA in the modern management of teeth affected by dens invaginatus.

Dens invaginatus is a dental anomaly that can result in loss of tooth vitality and the need for root canal treatment. The pulpal morphology of these teeth can be complex which makes successful root canal treatment difficult to achieve. To maintain vitality attempts have been made to prophylactically treat these teeth by sealing the invagination with a variety of materials. This paper describes the use of mineral trioxide aggregate (MTA) in both the prophylactic treatment of teeth with minor invaginations and the incorporation of MTA in the final obturation of non-vital teeth with invaginations with grossly atypical morphology.

Current forest carbon fixation fuels stream CO2 emissions.

Stream CO2 emissions contribute significantly to atmospheric climate forcing. While there are strong indications that groundwater inputs sustain these emissions, the specific biogeochemical pathways and timescales involved in this lateral CO2 export are still obscure. Here, via an extensive radiocarbon (14C) characterisation of CO2 and DOC in stream water and its groundwater sources in an old-growth boreal forest, we demonstrate that the 14C-CO2 is consistently in tune with the current atmospheric 14C-CO2 level and shows little association with the 14C-DOC in the same waters. Our findings thus indicate that stream CO2 emissions act as a shortcut that returns CO2 recently fixed by the forest vegetation to the atmosphere. Our results expose a positive feedback mechanism within the C budget of forested catchments, where stream CO2 emissions will be highly sensitive to changes in forest C allocation patterns associated with climate and land-use changes.

Targeting of a CD8 T cell env epitope presented by HLA-B*5802 is associated with markers of HIV disease progression and lack of selection pressure.

In HIV-infected persons, certain HLA class I alleles are associated with effective control of viremia, while others are associated with rapid disease progression. Among the most divergent clinical outcomes are the relatively good prognosis in HLA-B*5801 expressing persons and poor prognosis with HLA-B*5802. These two alleles differ by only three amino acids in regions involved in HLA-peptide recognition. This study evaluated a cohort of over 1000 persons with chronic HIV clade C virus infection to determine whether clinical outcome differences associated with B*5801 (n = 93) and B*5802 ( n = 259) expression are associated with differences in HIV-1-specific CD8 (+) T cell responses. The overall breadth and magnitude of HIV-1-specific CD8(+) T cell responses were lower in persons expressing B*5802, and epitope presentation by B*5802 contributed significantly less to the overall response as compared to B*5801-restricted CD8 (+) T cells. Moreover, viral load in B*5802-positive persons was higher and CD4 cell counts lower when this allele contributed to the overall CD8 (+) T cell response, which was detected exclusively through a single epitope in Env. In addition, persons heterozygous for B*5802 compared to persons homozygous for other HLA-B alleles had significantly higher viral loads. Viral sequencing revealed strong selection pressure mediated through B*5801-restricted responses but not through B*5802. These data indicate that minor differences in HLA sequence can have a major impact on epitope recognition, and that selective targeting of Env through HLA-B*5802 is at least ineffectual if not actively adverse in the containment of viremia. These results provide experimental evidence that not all epitope-specific responses contribute to immune containment, a better understanding of which is essential to shed light on mechanisms involved in HIV disease progression.

Testing the steady-state water chemistry model predictions of pre-industrial lake pH with paleolimnological data from northern Sweden.

Criteria are needed for distinguishing naturally acid water from that acidified by air pollution, especially in the organic-rich waters of northern Sweden. The Steady-State Water Chemistry Model (SSWC) was augmented to include organic acidity so that it could predict pre-industrial pH in organic-rich waters. The resulting model predictions of pre-industrial ANC and pH were then tested against diatom predictions of pre-industrial pH and alkalinity in 58 lakes from N. Sweden (after alkalinity was converted to ANC using the CBALK method). The SSWC Model's predictions of pre-industrial lake pH in N. Sweden did not correspond well with the diatom predictions, even when accounting for the uncertainty in the diatom model. This was due to the SSWC's sensitivity to short-term fluctuations in contemporary water chemistry. Thus the SSWC Model is not suitable for judging the acidification of individual lakes in areas such as northern Sweden where the degree of chronic acidification is small, or without a good average value of contemporary water chemistry. These results should be considered when assessing the accuracy of critical loads calculated using SSWC.

Dens invaginatus. Part 1: classification, prevalence and aetiology.

AIM: To review and discuss the aetiology, prevalence and classification of this dental anomaly together with the morphology of an invagination and the most appropriate nomenclature. SUMMARY: This review considers the different possible nomenclatures and concludes that dens invaginatus is the most appropriate description. The paper highlights the different reported prevalence figures and concludes that the problem is probably one of the most common of the dental developmental abnormalities with maxillary lateral incisors most commonly affected. The paper suggests that the classification system described by Oehlers (1957a) is probably the most clinically relevant and that the morphological features associated with this problem may increase the risk of pulpal pathology developing and complicate any possible endodontic treatment. KEY LEARNING POINTS: * The aetiology of dens invaginatus is still unknown, although there is some evidence that it may be genetic in origin. * The problem is probably more prevalent than most clinicians are aware of and this is because of the diagnostic difficulties associated with the anomaly. * The nature of the problem may increase the risk of pulp disease and complicate any root canal treatment.

Dens invaginatus. Part 2: clinical, radiographic features and management options.

AIM: To describe the possible clinical and radiographic features of this developmental anomaly, review previous treatment recommendations and suggest management options based on the classification of the problem. SUMMARY: This paper describes the clinical and radiographic features related to the different types of dens invaginatus and highlights those features which may indicate the presence of a previously undetected invagination. Aids to clinical diagnosis are described together with a description of the possible radiographic features, which may suggest the presence of an invagination. Previous treatment suggestions are described and suggestions as to possible management options, based on current endodontic knowledge and the classification of the problems are described. KEY LEARNING POINTS: * Thorough clinical and radiographic examination is required to diagnose and successfully treat minor to severe invaginations. * Modern clinical techniques may facilitate the management of invaginations once considered untreatable.

Public health response to an imported case of canine melioidosis.

Melioidosis in humans presents variably as fulminant sepsis, pneumonia, skin infection and solid organ abscesses. It is caused by Burkholderia pseudomallei, which in the United States is classified as a select agent, with "potential to pose a severe threat to both human and animal health, to plant health or to animal and plant products" (Federal Select Agent Program, http://www.selectagents.gov/, accessed 22 September 2016). Burkholderia pseudomallei is found in soil and surface water in the tropics, especially South-East Asia and northern Australia, where melioidosis is endemic. Human cases are rare in the United States and are usually associated with travel to endemic areas. Burkholderia pseudomallei can also infect animals. We describe a multijurisdictional public health response to a case of subclinical urinary B. pseudomallei infection in a dog that had been adopted into upstate New York from a shelter in Thailand. Investigation disclosed three human contacts with single, low-risk exposures to the dog's urine at his residence, and 16 human contacts with possible exposure to his urine or culture isolates at a veterinary hospital. Contacts were offered various combinations of symptom/fever monitoring, baseline and repeat B. pseudomallei serologic testing, and antibiotic post-exposure prophylaxis, depending on the nature of their exposure and their personal medical histories. The dog's owner accepted recommendations from public health authorities and veterinary clinicians for humane euthanasia. A number of animal rescue organizations actively facilitate adoptions into the United States of shelter dogs from South-East Asia. This may result in importation of B. pseudomallei into almost any community, with implications for human and animal health.

Molecular analysis of the klarsicht gene and its role in nuclear migration within differentiating cells of the Drosophila eye.

BACKGROUND: The temporally regulated, cell-type-specific transport of organelles has great biological significance, yet little is known about the regulation of organelle transport during development. The Drosophila gene klarsicht is required for temporally regulated lipid droplet transport in developing embryos and for the stereotypical nuclear migrations in differentiating cells of the developing eye. Klarsicht is thought to coordinate the function of several molecular motors bound to a single lipid droplet or to facilitate the attachment of dynein to the cargo, but it is not known whether Klarsicht affects motors directly or indirectly. RESULTS: Here, we have cloned the klarsicht gene and shown that it encodes a unique large protein. Drosophila klarsicht null mutants were viable, with obvious defects only in adult eye morphology. Epitope-tagged Klarsicht expressed in the eye from a transgene was perinuclear. In flies carrying transgenes that express markers for microtubule plus and minus ends, microtubules in differentiating cells of the eye were oriented with their plus ends apical and their minus ends at the nucleus. CONCLUSIONS: Drosophila klarsicht null mutants were viable and fertile, demonstrating that klarsicht is essential only for specific motor protein functions. Perinuclear localization of Klarsicht protein indicates that Klarsicht has a direct mechanical role in nuclear migration. Taken together with the finding that the minus ends of the microtubules are associated with the photoreceptor nuclei, the observation that Klarsicht is largely perinuclear supports the idea that Klarsicht associates with dynein, consistent with a model in which Klarsicht assists dynein in 'reeling in' the nucleus.