Persistent influence of precession on northern ice sheet variability since the early Pleistocene.

Prior to ~1 million years ago (Ma), variations in global ice volume were dominated by changes in obliquity; however, the role of precession remains unresolved. Using a record of North Atlantic ice rafting spanning the past 1.7 million years, we find that the onset of ice rafting within a given glacial cycle (reflecting ice sheet expansion) consistently occurred during times of decreasing obliquity whereas mass ice wasting (ablation) events were consistently tied to minima in precession. Furthermore, our results suggest that the ubiquitous association between precession-driven mass wasting events and glacial termination is a distinct feature of the mid to late Pleistocene. Before then (increasing), obliquity alone was sufficient to end a glacial cycle, before losing its dominant grip on deglaciation with the southward extension of Northern Hemisphere ice sheets since ~1 Ma.

Clinical description & molecular modeling of novel MAX pathogenic variant causing pheochromocytoma in family, supports paternal parent-of-origin effect.

The titular member of the MAX network of proteins, MYC-associated factor X (MAX), serves an important regulatory function in transcription of E-box genes associated with cell proliferation, differentiation, and apoptosis. Wild type MAX dimerizes with both MYC and MAD, both of which are members of the MAX network, and can promote or repress cell functions as needed. However, pathogenic variants in MAX are known to upset this balance, leading to uncontrolled oncogenic activity and disease phenotypes such as paragangliomas and pheochromocytomas. We report a 58-year-old male and his 32-year-old daughter, both of which have a history of pheochromocytoma and the unique nonsense MAX variant c.271C>T (p.Q91X). These individuals were diagnosed with pheochromocytomas in their early twenties that were later removed through corrective surgery. The father now presents with recurrent symptoms of hypertension, hyperhidrosis, and headaches, which accompany new pheochromocytomas of his remaining adrenal gland. Pathogenicity of this MAX variant is proven through molecular modeling. The case of this father-daughter pair supports both heritability of pheochromocytoma and the paternal parent-of-origin effect for MAX pathogenic variants.

Type 1 sialidosis presenting with ataxia, seizures and myoclonus with no visual involvement.

Sialidosis is an autosomal recessive lysosomal storage disease caused by pathogenic variants in NEU1 which encodes lysosomal sialidase (neuraminidase 1). Lysosomal neuraminidase catalyzes the removal of terminal sialic acid molecules from glycolipids, glycoproteins and oligosaccharides. Sialidosis is classified into two types, based on phenotype and age of onset. Patients with the milder type 1 typically present late, usually in the second or third decade, with myoclonus, ataxia and visual defects. Type 2 is more severe and presents earlier with coarse facial features, developmental delay, hepatosplenomegaly and dysostosis multiplex. Presentation and severity of the disease are related to whether lysosomal sialidase is inactive or there is some residual activity. Diagnosis is suspected based on clinical features and increased urinary bound sialic acid excretion and confirmed by genetic testing showing pathogenic variants in NEU1. We report a patient with type 1 sialidosis who presented mainly with ataxia and both generalized and myoclonic seizures but no visual involvement. Whole exome sequencing of the proband detected compound heterozygous likely pathogenic variants (S182G and G227R) in NEU1.

Unabated occupational risk in a patient with rheumatoid pulmonary fibrosis.

BACKGROUND: This case highlights the importance of considering hypersensitivity pneumonitis (HP) in the differential diagnosis of interstitial lung disease (ILD) and of obtaining an occupational history so that remediable risk factors may be identified and managed. AIMS: To report a case of a chicken sexer with severe rheumatoid arthritis (RA) who developed progressively worsening dyspnoea and restrictive lung disease associated with pulmonary fibrosis. METHODS: Clinical investigation included physical examination, occupational history, pulmonary function tests (PFTs), chest imaging and bronchoalveolar lavage (BAL), as well as serological tests including standard IgE bird feather mixture and local IgG precipitin preparation to chicken excrement. Lung histopathology was examined post-mortem. RESULTS: The patient had worked as a chicken sexer for 29 years with limited control of exposure to chicken bioaerosols. PFTs initially showed mild restriction with a moderate gas transfer defect and computerized tomography of the chest exhibited extensive interstitial infiltrates throughout with severe honeycombing at the bases. Cytology from a BAL revealed multinucleated giant cells (MNGs). Specific serologic tests for bird antigens were negative. Histopathology demonstrated diffuse interstitial fibrosis with honeycombing, poorly formed granulomas and MNGs. CONCLUSIONS: Findings were consistent with a diagnosis of HP with RA-associated ILD. The patient's history of severe RA biased the diagnosis to one of RA-associated ILD and her occupational risk had been less emphatically addressed. Obtaining a thorough occupational history can uncover exposures to workplace respiratory hazards and may create opportunities for intervention to limit morbidity from chronic lung disease.

Computational fluid dynamics modeling of Bacillus anthracis spore deposition in rabbit and human respiratory airways.

Three-dimensional computational fluid dynamics and Lagrangian particle deposition models were developed to compare the deposition of aerosolized Bacillus anthracis spores in the respiratory airways of a human with that of the rabbit, a species commonly used in the study of anthrax disease. The respiratory airway geometries for each species were derived respectively from computed tomography (CT) and µCT images. Both models encompassed airways that extended from the external nose to the lung with a total of 272 outlets in the human model and 2878 outlets in the rabbit model. All simulations of spore deposition were conducted under transient, inhalation-exhalation breathing conditions using average species-specific minute volumes. Two different exposure scenarios were modeled in the rabbit based upon experimental inhalation studies. For comparison, human simulations were conducted at the highest exposure concentration used during the rabbit experimental exposures. Results demonstrated that regional spore deposition patterns were sensitive to airway geometry and ventilation profiles. Due to the complex airway geometries in the rabbit nose, higher spore deposition efficiency was predicted in the nasal sinus compared to the human at the same air concentration of anthrax spores. In contrast, higher spore deposition was predicted in the lower conducting airways of the human compared to the rabbit lung due to differences in airway branching pattern. This information can be used to refine published and ongoing biokinetic models of inhalation anthrax spore exposures, which currently estimate deposited spore concentrations based solely upon exposure concentrations and inhaled doses that do not factor in species-specific anatomy and physiology for deposition.

Endpoint comparison for bone mineral density measurements in North Central Cancer Treatment Group cancer clinical trials N02C1 and N03CC (Alliance).

UNLABELLED: Bone mineral density (BMD) measurement can vary depending upon anatomical site, machine, and normative values used. This analysis compared different BMD endpoints in two clinical trials. Trial results differed across endpoints. Future clinical trials should consider inclusion of multiple endpoints in sensitivity analysis to ensure sound overall study conclusions. INTRODUCTION: Methodological issues hamper efficacy assessment of osteoporosis prevention agents in cancer survivors. Osteoporosis diagnosis can vary depending upon which bone mineral density (BMD) anatomical site and machine is used and which set of normative values are applied. This analysis compared different endpoints for osteoporosis treatment efficacy assessment in two clinical studies. METHODS: Data from North Central Cancer Treatment Group phase III clinical trials N02C1 and N03CC (Alliance) were employed involving 774 patients each comparing two treatments for osteoporosis prevention. Endpoints for three anatomical sites included raw BMD score (RawBMD); raw machine-based, sample-standardized, and reference population-standardized T scores (RawT, TSamp, TRef); and standard normal percentile corresponding to the reference population-standardized T score (TPerc). For each, treatment arm comparison was carried out using three statistical tests using change and percentage change from baseline (CB, %CB) at 1 year. RESULTS: Baseline correlations among endpoints ranged from 0.79 to 1.00. RawBMD and TPerc produced more statistically significant results (14 and 19 each out of 36 tests) compared to RawT (11/36), TSamp (8/36), and TRef (7/36). Spine produced the most statistically significant results (26/60) relative to femoral neck (20/60) and total hip (13/60). Lastly, CB resulted in 44 statistically significant results out of 90 tests, whereas %CB resulted in only 15 significant results. CONCLUSIONS: Treatment comparisons and interpretations were different across endpoints and anatomical sites. Transforming via sample statistics provided similar results as transforming via reference or machine-based norms. However, RawBMD and TPerc may be more sensitive to change as clinical trial endpoints.

Diagnosis, treatment, control, and prevention of infections caused by Rhodococcus equi in foals.

Rhodococcus equi, a gram-positive facultative intracellular pathogen, is one of the most common causes of pneumonia in foals. Although R. equi can be cultured from the environment of virtually all horse farms, the clinical disease in foals is endemic at some farms, sporadic at others, and unrecognized at many. On farms where the disease is endemic, costs associated with morbidity and mortality attributable to R. equi may be very high. The purpose of this consensus statement is to provide recommendations regarding the diagnosis, treatment, control, and prevention of infections caused by R. equi in foals.

Rhodococcus equi: clinical manifestations, virulence, and immunity.

Pneumonia is a major cause of disease and death in foals. Rhodococcus equi, a gram-positive facultative intracellular pathogen, is a common cause of pneumonia in foals. This article reviews the clinical manifestations of infection caused by R. equi in foals and summarizes current knowledge regarding mechanisms of virulence of, and immunity to, R. equi. A complementary consensus statement providing recommendations for the diagnosis, treatment, control, and prevention of infections caused by R. equi in foals can be found in the same issue of the Journal.

Establishing nurse-led ventilator-associated pneumonia surveillance in paediatric intensive care.

Preventing ventilator-associated pneumonia (VAP) is one of the Department of Health 'Saving Lives' initiatives. Whereas morbidity and mortality from VAP is well-documented in adults, it is poorly studied in children. We describe the establishment of a nurse-led VAP surveillance programme as part of an overall drive for patient safety and healthcare-associated infection reduction. All children admitted to a tertiary referral paediatric intensive care unit over a four-month period were studied. VAP was defined as pneumonia occurring >48 h post intubation. Diagnostic criteria were: (i) radiological: new/progressive infiltrates, consolidation or cavitation on chest X-ray; (ii) clinical: > or = 3 of new onset purulent bronchial secretions, leucopaenia or leucocytosis, core temperature > or = 38.5 degrees C or < or = 36 degrees C without other cause, significant positive respiratory culture or culture from another relevant site of infection. A flow diagram and teaching programme was developed for bedside nurses to facilitate investigations of suspected VAP. The nurse in charge collected data daily at midnight until 24h post extubation, discharge or death. Suspected cases of VAP were referred to infection control for secondary verification. A total of 158 intubated children were admitted over four months with 58 excluded (ventilated <24 h). Full data were obtained on all 100 children. VAP incidence was 5.6 per 1000 ventilator-days. We report successful introduction of a nurse-led VAP surveillance programme. Data acquisition in this study was dependent on nursing workload, however, and placed a significant time burden on the study leads. Although a relatively low VAP rate was demonstrated, VAP bundles with automated surveillance are being introduced.

The influence of age and Rhodococcus equi infection on CD1 expression by equine antigen presenting cells

There is a distinct age-associated susceptibility of horses to Rhodococcus equi infection. Initial infection is thought to occur in the neonatal and perinatal period, and only foals less than 6 months of age are typically affected. R. equi is closely related and structurally similar to Mycobacterium tuberculosis, and causes similar pathologic lesions. Protective immune responses to M. tuberculosis involve classical major histocompatibility complex (MHC)-restricted T cells that recognize peptide antigen, as well as MHC-independent T cells that recognize mycobacterial lipid antigen presented by CD1 molecules. Given the structural similarity between these two pathogens and our previous observations regarding R. equi-specific, MHC-unrestricted cytotoxic T lymphocytes (CTL), we developed 3 related hypotheses: (1) CD1 molecules are expressed on equine antigen presenting cells (APC), (2) CD1 expression on APC is less in foals compared to adults and (3) infection with live virulent R. equi induces up-regulation of CD1 on both adult and perinatal APC. CD1 expression was examined by flow cytometric analysis using a panel of monoclonal CD1 antibodies with different species and isoform specificities. RESULTS: Three CD1 antibodies specific for CD1b showed consistent cross reactivity with both foal and adult monocyte-derived macrophages (MDM). CD1b and MHC class II expression were significantly higher on adult MDM compared with foals. R. equi infected MDM showed significantly lower expression of CD1b, suggesting that infection with this bacterium induces down-regulation of CD1b on the cell surface. Histograms from dual antibody staining of peripheral blood mononuclear cells also revealed that 45-71% of the monocyte population stained positive for CD1b, and that the majority of these also co-expressed MHC II molecules, indicating that they were APC. The anti-CD1 antibodies showed no binding or minimal binding to bronchoalveolar lavage (BAL)-derived macrophages.

Clinical outcomes after a diagnosis of brain metastases in patients with estrogen- and/or human epidermal growth factor receptor 2-positive versus triple-negative breast cancer.

BACKGROUND: Women with triple-negative (TN) breast cancer are at increased risk of distant metastases and have reduced survival versus other breast cancer patients. Relative survival of women with TN breast cancer who develop brain metastases is unknown. METHODS: Patients with breast cancer who developed brain metastases at our institution from 1993 to 2006 were reviewed. Four survival time intervals were compared in patients with TN disease and those with non-TN disease: initial diagnosis to distant metastases, distant metastases to brain metastases, brain metastases to death, and overall diagnosis to death. RESULTS: One hundred and eighteen patients were identified. Fifty-one (50%) of 103 were estrogen receptor positive, 26 (39%) of 67 were human epidermal growth factor receptor 2 positive, and 20 (22%) of 91 were TN. Survival times were shorter for TN patients, with overall survival of 26 months in TN patients versus 49 months for non-TN patients. In TN patients, time to development of distant metastases, brain metastases, and death after brain metastases was shorter than in non-TN patients. CONCLUSION: Patients with TN disease were more likely to develop distant metastases earlier than non-TN patients, developed brain metastases sooner, and had shorter overall survival.

Experimental Rhodococcus equi and equine infectious anemia virus DNA vaccination in adult and neonatal horses: effect of IL-12, dose, and route.

Improving the ability of DNA-based vaccines to induce potent Type1/Th1 responses against intracellular pathogens in large outbred species is essential. Rhodoccocus equi and equine infectious anemia virus (EIAV) are two naturally occurring equine pathogens that also serve as important large animal models of neonatal immunity and lentiviral immune control. Neonates present a unique challenge for immunization due to their diminished immunologic capabilities and apparent Th2 bias. In an effort to augment R. equi- and EIAV-specific Th1 responses induced by DNA vaccination, we hypothesized that a dual promoter plasmid encoding recombinant equine IL-12 (rEqIL-12) would function as a molecular adjuvant. In adult horses, DNA vaccines induced R. equi- and EIAV-specific antibody and lymphoproliferative responses, and EIAV-specific CTL and tetramer-positive CD8+ T lymphocytes. These responses were not enhanced by the rEqIL-12 plasmid. In neonatal foals, DNA immunization induced EIAV-specific antibody and lymphoproliferative responses, but not CTL. The R. equi vapA vaccine was poorly immunogenic in foals even when co-administered with the IL-12 plasmid. It was concluded that DNA immunization was capable of inducing Th1 responses in horses; dose and route were significant variables, but rEqIL-12 was not an effective molecular adjuvant. Additional work is needed to optimize DNA vaccine-induced Th1 responses in horses, especially in neonates.

Disease management: what have we learned so far?

Disease management (DM) is becoming an increasingly important tool for use in end-stage renal disease (ESRD). The goal of a DM program is to offer a continuum of care that uses guidelines and case management protocols to prevent acute care episodes, achieve improved outcomes and reduce health care costs. This article reviews the theory behind DM, describes key components of DM programs and explains the financial incentives for DM in ESRD. Of key importance in the increasing role of DM for ESRD has been the development of nationally recognized guidelines, the effects of which are now beginning to emerge. At the same time, recent studies have identified targeted opportunities for DM programs to improve outcomes and costs, including anemia management, dialysis dose, and vascular access. DM, through the use of guidelines and targeted toward these and other areas, has the potential to significantly impact the quality of care provided to ESRD patients.

From coping with life to coping with death: problematic integration for the seriously ill elderly.

Decisions made by and for elderly patients nearing death frequently perpetuate unwanted suffering and dependence. This article extends the argument that Babrow's (1992, 1995) problematic integration theory can provide insights into why communication fails to produce desired outcomes for such patients. Open-ended responses obtained in face-to-face interviews with 142 elderly dialysis patients and mailed surveys of 393 dialysis unit nurses were examined to better understand how patients and nurses reconciled incompatible probabilistic and evaluativejudgments. Results indicate that patients seek information that will enable them to cope with debilitating dialysis treatments rather than information nurses believe is necessary for them to make informed choices about whether to undergo such treatments. The tension between the information patients want to successfully cope with life and the information they need to decide intelligently about treatments that forestall death constitutes a key reason why communication about end-of-life issues is frequently flawed. Our analysis of these communication flaws leads to specific recommendations for how this tension can be eased, which in turn may better prepare patients to make the transition from coping with life to coping with death.

Immunity to Rhodococcus equi: antigen-specific recall responses in the lungs of adult horses.

Rhodococcal pneumonia is an important disease of young horses that is not seen in immunocompetent adults. Since all foals are normally exposed to Rhodococcus equi in their environment, we hypothesized that most develop protective immune responses. Furthermore, these antigen-specific responses were hypothesized to operate throughout adult life to prevent rhodococcal pneumonia. A better understanding of the mechanisms of immune clearance in adult horses would help define the requirements for an effective vaccine in foals. Adult horses were challenged with virulent R. equi by intrabronchial inoculation into the right lung, and pulmonary immune responses were followed for 2 weeks by bronchoalveolar lavage. Local responses in the inoculated right lung were compared to the uninfected left lung and peripheral blood. Challenged horses rapidly cleared R. equi infection without significant clinical signs. Clearance of bacteria was associated with increased mononuclear cells in bronchoalveolar lavage fluid (primarily lymphocytes) and inversion of the normal macrophage:lymphocyte ratio. There was no significant increase in neutrophils at 7 days post-challenge. Flow cytometric analysis of bronchoalveolar lavage fluid demonstrated that clearance correlated with significant increases in pulmonary T-lymphocytes, both CD4+ and CD8+. Prior to challenge, most adult horses demonstrated low proliferative responses when pulmonary lymphocytes were stimulated with soluble R. equi ex vivo. However, clearance was associated with marked increases in lymphoproliferative responses to soluble R. equi antigen and recombinant VapA, a virulence associated protein of R. equi and candidate immunogen. These results are compatible with previous work in mice which showed that both CD4+ and CD8+ T-cells play a role in immune clearance of R. equi. Recognition of VapA in association with clearance lends further support to its testing as an immunogen. Importantly, the cellular responses to R. equi challenge were relatively compartmentalized. Responses were more marked and the sensitivity to antigen dose was increased at the site of challenge. The blood, including peripheral blood mononuclear cells, was an insensitive indicator of local pulmonary responses.

Virulence plasmid of Rhodococcus equi contains inducible gene family encoding secreted proteins.

Rhodococcus equi causes severe pyogranulomatous pneumonia in foals. This facultative intracellular pathogen produces similar lesions in immunocompromised humans, particularly in AIDS patients. Virulent strains of R. equi bear a large plasmid that is required for intracellular survival within macrophages and for virulence in foals and mice. Only two plasmid-encoded proteins have been described previously; a 15- to 17-kDa surface protein designated virulence-associated protein A (VapA) and an antigenically related 20-kDa protein (herein designated VapB). These two proteins are not expressed by the same R. equi isolate. We describe here the substantial similarity between VapA and VapB. Moreover, we identify three additional genes carried on the virulence plasmid, vapC, -D, and -E, that are tandemly arranged downstream of vapA. These new genes are members of a gene family and encode proteins that are approximately 50% homologous to VapA, VapB, and each other. vapC, -D, and -E are found only in R. equi strains that express VapA and are highly conserved in VapA-positive isolates from both horses and humans. VapC, -D, and -E are secreted proteins coordinately regulated by temperature with VapA; the proteins are expressed when R. equi is cultured at 37 degrees C but not at 30 degrees C, a finding that is compatible with a role in virulence. As secreted proteins, VapC, -D, and -E may represent targets for the prevention of rhodococcal pneumonia. An immunologic study using VapA-specific antibodies and recombinant Vap proteins revealed no evidence of cross-reactivity despite extensive sequence similarity over the carboxy terminus of all four proteins.

Improving advance care planning by accommodating family preferences.

CONTEXT: Family members often lack the knowledge of patients' values and preferences needed to function well as surrogate decision-makers. OBJECTIVE: To determine whether differences in values and preferences for the advance care planning process may be reasons family members are inadequately informed to act as surrogates. DESIGN: Face-to-face and telephone surveys using structured questionnaires. PARTICIPANTS: Two hundred forty-two pairs of dialysis patients and their designated surrogates. MAIN OUTCOME MEASURES: Content and number of end-of-life care discussions; patient and surrogate attitudes toward having patients express preferences explicitly; factors most important to surrogates in decision making; and within-pair agreement about the values of suffering and certainty. RESULTS: Ninety percent of patients designated a family member as their surrogate. In most cases, having more conversations about end-of-life issues did not increase surrogate knowledge of patients' values or preferences. Surrogates wanted written and oral instructions more often than patients wanted to provide them (62% vs. 39%, p < 0.001). Knowing the patient's wish to stop treatment in the present condition was more important to most surrogates than the physician's recommendation to stop treatment (62% vs. 45%, p < 0.001). Compared to patients, surrogates were less likely to want to prolong the patient's life if it entailed suffering (12% vs. 23%, p < 0.01) and were more concerned about being certain before stopping life-sustaining treatments (85% vs. 77%, p < 0.02). CONCLUSIONS: Differences in preferences for the advance care planning process between patients and their surrogates and failure to discuss specific end-of-life values and preferences may explain why surrogates often lack information needed to serve as surrogate decision-makers.