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Breast cancer is a heterogeneous disease and can be classified based on gene expression profiles that reflect distinct epithelial subtypes. We identify prostate-derived ETS factor (PDEF) as a mediator of mammary luminal epithelial lineage-specific gene expression and as a factor required for tumorigenesis in a subset of breast cancers. PDEF levels strongly correlate with estrogen receptor (ER)-positive luminal breast cancer, and PDEF transcription is inversely regulated by ER and GATA3. Furthermore, PDEF is essential for luminal breast cancer cell survival and is required in models of endocrine resistance. These results offer insights into the function of this ETS factor that are clinically relevant and may be of therapeutic value for patients with breast cancer treated with endocrine therapy., (Copyright © 2013 Elsevier Inc. All rights reserved.)

Legionella-associated respiratory failure has a high mortality, despite modern ventilation modalities. Extracorporeal membrane oxygenation (ECMO) is used to achieve gas exchange independent of pulmonary function in patients with severe respiratory failure. This was a retrospective review of the management and outcome of patients with Legionella-associated respiratory failure treated with ECMO support in a large ECMO center over the past 10 years. A retrospective review of patients with confirmed Legionella-associated severe respiratory failure managed with ECMO support at a single center. Between 2000 and 2010, 19 patients with severe respiratory failure caused by Legionella were managed with ECMO after failure to respond to conventional intensive care management. Median PaO2/FiO2 ratio was 66 and median pCO2 was 60 torr. Sixteen patients (84%) survived to hospital discharge. Extracorporeal membrane oxygenation should be considered in patients with Legionella-associated respiratory failure, who have failed conventional ventilation.

Dynamic actin cytoskeletal reorganization is integral to cell motility. Profilins are well-characterized regulators of actin polymerization; however, functional differences among coexpressed profilin isoforms are not well defined. Here, we demonstrate that profilin-1 and profilin-2 differentially regulate membrane protrusion, motility, and invasion; these processes are promoted by profilin-1 and suppressed by profilin-2. Compared to profilin-1, profilin-2 preferentially drives actin polymerization by the Ena/VASP protein, EVL. Profilin-2 and EVL suppress protrusive activity and cell motility by an actomyosin contractility-dependent mechanism. Importantly, EVL or profilin-2 downregulation enhances invasion in vitro and in vivo. In human breast cancer, lower EVL expression correlates with high invasiveness and poor patient outcome. We propose that profilin-2/EVL-mediated actin polymerization enhances actin bundling and suppresses breast cancer cell invasion., (Copyright © 2012 Elsevier Inc. All rights reserved.)

The routes of nosocomial hepatitis B virus (HBV) transmission have changed over the years. Initiatives to prevent transfusion-associated HBV and healthcare worker-to-patient transmission have had a positive impact on these transmission routes. Recent reports of outbreaks of nosocomial HBV have implicated breaches in standard precautions as important causes of HBV transmission. This report describes a nosocomial outbreak of HBV infection in the Republic of Ireland, which occurred between January 2005 and March 2006. The outbreak was detected following identification of a case of acute HBV infection in a patient whose only risk factor was a recent surgical procedure. The extensive multi-agency investigation that followed revealed that the patient was one of five cases of acute HBV infection and that four separate transmission events between infectious cases had occurred in two different hospitals over a 15-month period. A definitive cause for each transmission event was not identified, although lapses in adherence to standard precautions, safe injection and phlebotomy practices could not be ruled out. Two secondary cases of acute HBV infection in community contacts of two of the nosocomial cases were identified. Phylogenetic analysis proved a useful tool in confirming infection with a pre-core HBV mutant and viral transmission between the seven patients. A patient notification exercise involving 1028 potentially exposed patients found no evidence of additional cases of nosocomial HBV infection. These findings highlight the importance of consistent application of standard precautions., (Copyright © 2011 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.)

Chuvash polycythemia is a rare congenital form of polycythemia caused by homozygous R200W and H191D mutations in the VHL (von Hippel-Lindau) gene, whose gene product is the principal negative regulator of hypoxia-inducible factor. However, the molecular mechanisms underlying some of the hallmark abnormalities of Chuvash polycythemia, such as hypersensitivity to erythropoietin, are unclear. Here we show that VHL directly binds suppressor of cytokine signaling 1 (SOCS1) to form a heterodimeric E3 ligase that targets phosphorylated JAK2 (pJAK2) for ubiquitin-mediated destruction. In contrast, Chuvash polycythemia-associated VHL mutants have altered affinity for SOCS1 and do not engage with and degrade pJAK2. Systemic administration of a highly selective JAK2 inhibitor, TG101209, reversed the disease phenotype in Vhl(R200W/R200W) knock-in mice, an experimental model that recapitulates human Chuvash polycythemia. These results show that VHL is a SOCS1-cooperative negative regulator of JAK2 and provide biochemical and preclinical support for JAK2-targeted therapy in individuals with Chuvash polycythemia.

Non-small cell lung cancer (NSCLC) is the leading cause of cancer deaths worldwide. The oxygen-sensitive hypoxia inducible factor (HIF) transcriptional regulators HIF-1alpha and HIF-2alpha are overexpressed in many human NSCLCs, and constitutive HIF-2alpha activity can promote murine lung tumor progression, suggesting that HIF proteins may be effective NSCLC therapeutic targets. To investigate the consequences of inhibiting HIF activity in lung cancers, we deleted Hif-1alpha or Hif-2alpha in an established Kras(G12D)-driven murine NSCLC model. Deletion of Hif-1alpha had no obvious effect on tumor growth, whereas Hif-2alpha deletion resulted in an unexpected increase in tumor burden that correlated with reduced expression of the candidate tumor suppressor gene Scgb3a1 (HIN-1). Here, we identify Scgb3a1 as a direct HIF-2alpha target gene and demonstrate that HIF-2alpha regulates Scgb3a1 expression and tumor formation in human Kras(G12D)-driven NSCLC cells. AKT pathway activity, reported to be repressed by Scgb3a1, was enhanced in HIF-2alpha-deficient human NSCLC cells and xenografts. Finally, a direct correlation between HIF-2alpha and SCGB3a1 expression was observed in approximately 70% of human NSCLC samples analyzed. These data suggest that, whereas HIF-2alpha overexpression can contribute to NSCLC progression, therapeutic inhibition of HIF-2alpha below a critical threshold may paradoxically promote tumor growth by reducing expression of tumor suppressor genes, including Scgb3a1.

Hypoxia-inducible factor 1alpha (HIF-1alpha) and HIF-2alpha display unique and sometimes opposing activities in regulating cellular energy homeostasis, cell fate decisions, and oncogenesis. Macrophages exposed to hypoxia accumulate both HIF-1alpha and HIF-2alpha, and overexpression of HIF-2alpha in tumor-associated macrophages (TAMs) is specifically correlated with high-grade human tumors and poor prognosis. However, the precise role of HIF-2alpha during macrophage-mediated inflammatory responses remains unclear. To fully characterize cellular hypoxic adaptations, distinct functions of HIF-1alpha versus HIF-2alpha must be elucidated. We demonstrate here that mice lacking HIF-2alpha in myeloid cells (Hif2aDelta/Delta mice) are resistant to lipopolysaccharide-induced endotoxemia and display a marked inability to mount inflammatory responses to cutaneous and peritoneal irritants. Furthermore, HIF-2alpha directly regulated proinflammatory cytokine/chemokine expression in macrophages activated in vitro. Hif2aDelta/Delta mice displayed reduced TAM infiltration in independent murine hepatocellular and colitis-associated colon carcinoma models, and this was associated with reduced tumor cell proliferation and progression. Notably, HIF-2alpha modulated macrophage migration by regulating the expression of the cytokine receptor M-CSFR and the chemokine receptor CXCR4, without altering intracellular ATP levels. Collectively, our data identify HIF-2alpha as an important regulator of innate immunity, suggesting it may be a useful therapeutic target for treating inflammatory disorders and cancer.

Mutation of the von Hippel-Lindau (VHL) tumor suppressor protein at codon 200 (R200W) is associated with a disease known as Chuvash polycythemia. In addition to polycythemia, Chuvash patients have pulmonary hypertension and increased respiratory rates, although the pathophysiological basis of these symptoms is unclear. Here we sought to address this issue by studying mice homozygous for the R200W Vhl mutation (VhlR/R mice) as a model for Chuvash disease. These mice developed pulmonary hypertension independently of polycythemia and enhanced normoxic respiration similar to Chuvash patients, further validating VhlR/R mice as a model for Chuvash disease. Lungs from VhlR/R mice exhibited pulmonary vascular remodeling, hemorrhage, edema, and macrophage infiltration, and lungs from older mice also exhibited fibrosis. HIF-2alpha activity was increased in lungs from VhlR/R mice, and heterozygosity for Hif2a, but not Hif1a, genetically suppressed both the polycythemia and pulmonary hypertension in the VhlR/R mice. Furthermore, Hif2a heterozygosity resulted in partial protection against vascular remodeling, hemorrhage, and edema, but not inflammation, in VhlR/R lungs, suggesting a selective role for HIF-2alpha in the pulmonary pathology and thereby providing insight into the mechanisms underlying pulmonary hypertension. These findings strongly support a dependency of the Chuvash phenotype on HIF-2alpha and suggest potential treatments for Chuvash patients.

Von Hippel-Lindau (VHL) disease is caused by germline mutations in the VHL tumor suppressor gene, with Type 2B missense VHL mutations predisposing to renal cell carcinoma, hemangioblastoma and pheochromocytoma. Type 2B mutant pVHL is predicted to be defective in hypoxia inducible factor (HIF)-alpha regulation. Murine embryonic stem (ES) cells in which the endogenous wild-type Vhl gene was replaced with the representative Type 2B VHL hotspot mutation R167Q (Vhl(2B/2B)) displayed preserved physiological regulation of both HIF factors with slightly greater normoxic dysregulation of HIF-2alpha. Differentiated Vhl(2B/2B)-derived teratomas overexpressed joint HIF targets Vegf and EglN3 but not the HIF-1alpha-specific target Pfk1. Vhl(2B/2B) teratomas additionally displayed a growth advantage over Vhl(-/-)-derived teratomas, suggestive of a tight connection between perturbations in the degree and ratio of HIF-1alpha and HIF-2alpha stabilization and cell growth. Vhl(2B/2B) mice displayed mid-gestational embryonic lethality, whereas adult Vhl(2B/+) mice exhibited susceptibility to carcinogen-promoted renal neoplasia compared with wild-type littermates at 12 months. Our experiments support a model in which the representative Type 2B R167Q mutant pVhl produces a unique profile of HIF dysregulation, thereby promoting tissue-specific effects on cell growth, development and tumor predisposition.

The R200W mutation in the von Hippel-Lindau (VHL) tumor suppressor protein (pVHL) is unique in that it is not associated with tumor development, but rather with Chuvash polycythemia, a heritable disease characterized by elevated hematocrit and increased serum levels of erythropoietin and VEGF. Previous studies have implicated hypoxia-inducible factor-1alpha (HIF-1alpha) signaling in this disorder, although the effects of this mutation on pVHL function are not fully understood. In order to explore the mechanisms underlying the development of this polycythemia, we generated mice homozygous for the R200W mutation (Vhl(R/R)). Vhl(R/R) mice developed polycythemia highly similar to the human disease. The activity of HIF proteins, specifically the HIF-2alpha isoform, was upregulated in ES cells and tissues from Vhl(R/R) mice. Furthermore, we observed a striking phenotype in Vhl(R/R) spleens, with greater numbers of erythroid progenitors and megakaryocytes and increased erythroid differentiation of Vhl(R/R) splenic cells in vitro. These findings suggest that enhanced expression of key HIF-2alpha genes promotes splenic erythropoiesis, resulting in the development of polycythemia in Vhl(R/R) mice. This mouse model is a faithful recapitulation of this VHL-associated syndrome and represents a useful tool for studying polycythemias and investigating potential therapeutics.

Maintenance of oxygen homeostasis is critical for the survival of multicellular organs. As a result, both invertebrates and vertebrates have developed highly specialized mechanisms to sense changes in oxygen levels and to mount adequate cellular and systemic responses to these changes. Hypoxia, or low oxygen tension, occurs in physiological situations such as during embryonic development, as well as in pathological conditions such as ischemia, wound healing, and cancer. A primary effector of the adaptive response to hypoxia in mammals is the hypoxia-inducible factor (HIF) family of transcription regulators. These proteins activate the expression of a broad range of genes that mediate many of the responses to decreased oxygen concentration, including enhanced glucose uptake, increased red blood cell production, and the formation of new blood vessels via angiogenesis. This latter process is dynamic and results in the establishment of a mature vascular system that is indispensable for proper delivery of oxygen and nutrients to all cells in both normal tissue and hypoxic regions. Angiogenesis is essential for normal development and neoplastic disease as tumors must develop mechanisms to stimulate vascularization to meet increasing metabolic demands. The link between hypoxia and the regulation of angiogenesis is an area of intense research and the molecular details of this connection are still being elaborated. This chapter will provide an overview of current knowledge and highlight new insights into the importance of HIF and hypoxia in angiogenesis in both physiological and pathophysiological conditions.

Mutations in the von Hippel-Lindau (VHL) tumor suppressor gene cause tissue-specific tumors, with a striking genotype-phenotype correlation. Loss of VHL expression predisposes to hemangioblastoma and clear cell renal cell carcinoma, whereas specific point mutations predispose to pheochromocytoma, polycythemia, or combinations of hemangioblastoma, renal cell carcinoma, and/or pheochromocytoma. The VHL protein (pVHL) has been implicated in many cellular activities including the hypoxia response, cell cycle arrest, apoptosis, and extracellular matrix remodeling. We have expressed missense pVHL mutations in Vhl(-/-) murine embryonic stem cells to test genotype-phenotype correlations in euploid cells. We first examined the ability of mutant pVHL to direct degradation of the hypoxia inducible factor (HIF) subunits HIF1alpha and HIF2alpha. All mutant pVHL proteins restored proper hypoxic regulation of HIF1alpha, although one VHL mutation (VHL(R167Q)) displayed impaired binding to Elongin C. This mutation also failed to restore HIF2alpha regulation. In separate assays, these embryonic stem cells were used to generate teratomas in immunocompromised mice, allowing independent assessment of the effects of specific VHL mutations on tumor growth. Surprisingly, teratomas expressing the VHL(Y112H) mutant protein displayed a growth disadvantage, despite restoring HIFalpha regulation. Finally, we observed increased microvessel density in teratomas derived from Vhl(-/-) as well as VHL(Y112H), VHL(R167Q), and VHL(R200W) embryonic stem cells. Together, these observations support the hypothesis that pVHL plays multiple roles in the cell, and that these activities can be separated via discrete VHL point mutations. The ability to dissect specific VHL functions with missense mutations in a euploid model offers a novel opportunity to elucidate the activities of VHL as a tumor suppressor.

Caregiving is an important component in the management of patients with a tracheostomy or laryngectomy. The purpose of this integrative research literature review was to gain a better understanding of the impact of caregiving for adults and children with laryngectomy or tracheostomy on the patient, the family, and the caregiver. Patients who had undergone laryngectomy or tracheostomy included those with and without cancer. This integrated review of the literature on caregiving in this population demonstrates the dearth of studies on this subject. Despite the significance of the caregiving role, few studies have addressed caregiving, and those that have are primarily descriptive. Studies are needed that develop and test interventions to assist caregivers in adaptation to their role, identification of methods of decreasing caregiver burden and strain, and coordination of resources to support patients and caregivers of patients with tracheostomies and laryngectomies.

In March, 2002, the Society of Otorhinolaryngology and Head-Neck Nurses, Inc. (SOHN) conducted a web-based survey of members' knowledge of and satisfaction with its portfolio of products and services. This paper reports on the process of developing and conducting the survey, as well as its findings. A new "Volunteer Agreement/Code of Conduct", piloted for this team's work is introduced. General and specific recommendations are put forth for SOHN members and leaders, including useful information to facilitate work for future survey teams.

As the 1997 Nurse in Washington Intern for SOHN, I was awed by the quality and quantity of information and experiences shared during the workshop. The three major concerns in healthcare policy on Capitol Hill are cost, quality, and access. Healthcare costs have escalated at tremendous speed, bypassing the growth of the Gross Domestic Product. Medicare is projected to go broke by 2007. The United States population is aging rapidly. The Federal Government must make changes to Medicare and Medicaid legislation or the U.S. Treasury may be consumed. As costs are cut, quality and access must be ensured. These are years of rapid change in healthcare. Nurses face many challenges and have many opportunities to participate in and influence the formation of healthcare policy. Nurses must be armed with information about key players, the processes, and what nursing can contribute to the healthcare system. We need to step up to the plate; we need to be part of the solution.

The types of organism causing septicaemia in patients with AIDS and without AIDS at Westminster Hospital were examined prospectively over a period of 2 years (1990-1991). Altogether 417 episodes of septicaemia were diagnosed, 148 (35%) of which were in patients with AIDS. Of septicaemias in patients with AIDS, 53 (36%) were caused by mycobacteria. Non-mycobacterial septicaemias were associated with IV access devices in 58 (61%) of patients with AIDS and in 50 (19%) of those without AIDS. Gram-negative organisms were responsible for septicaemia associated with IV access devices in 16 (28%) of 58 patients with AIDS and in 8 (16%) of 50 patients without AIDS. Non-typhoidal Salmonella species or Shigella species caused 13 (31%) of 42 episodes of septicaemia caused by Gram-negative organisms in patients with AIDS. These findings have influenced the strategy for empirical therapy of septicaemia in patients with AIDS at Westminster Hospital.

The Northwick Park Infection Consultation Service (ICS) is a collaborative service operated by the departments of Medical Microbiology and Infectious Diseases where personnel and skills are combined. Its aim is to improve the availability and effectiveness of consultation for infection-related problems. This paper sets out the framework for establishing an ICS and also details the general distribution of infection identified by the Northwick Park ICS in a study carried out between September 1987 and July 1990. Part II assesses the contribution that the ICS made to the management of infection. One thousand and thirty-eight (1038) patients were seen on the ICS. Seventy-five per cent (776) were judged to be infected and in 691 this was a probable or certain diagnosis. Skin and subcutaneous tissue, respiratory tract, and genito-urinary tract infections accounted for 64% of the total. Eighty-seven per cent of infections required treatment with intravenous antibiotics, 22% were associated with concomitant bacteraemia, and 2.7% of patients died as a direct result of their infection. Sixty-four per cent of consultations were unsolicited and arose from laboratory results or the clinical information on the form accompanying the specimen: over one quarter were initiated before results were available. These infections were no different in either severity or nature from those identified by solicited requests to either department. Fifty-three per cent of consultations had a moderate to high clinical component. The results emphasise the importance of infection in hospitals and highlight the advantages of a collaborative approach from the departments of Medical Microbiology and Infectious Diseases.

The establishment of Infectious Disease teams combining microbiological and clinical expertise has recently been recommended by a joint working part of the Royal College of Physicians and the Royal College of Pathologists. The Northwick Park Infection Consultation Service (ICS) has been operating on these lines since 1983; details are given in Part I. Part II assesses the contribution that the ICS has made to the management of infection in a study of 1038 patients undertaken between September 1987 and July 1990. The areas of patient diagnosis, treatment, investigation and isolation were examined to assess the appropriateness of the attending doctor's management of infection and the benefits resulting from recommendations made by the ICS. At the time of consultation the correct diagnosis had already been made or considered in 93% of patients, essential investigations needed to confirm or refute the diagnosis performed in 92%, and side-room isolation correctly instituted in 81% of patients requiring it. However, 41% of 776 infected patients were receiving suboptimal treatment: this was significantly more frequent in unsolicited consultations (P less than 0.05). Advice was given following consultation in 893 of 1038 patients (86%) and related to treatment (66%), investigation (41%), diagnosis (30%) and patient isolation (4%). Of 844 patients where receipt of advice could be accurately assessed, it was taken fully in 708 (84%), partly in III (13%), and went unheeded in 25 (3%). Advice on diagnosis or investigation enabled the correct diagnosis to be reached in 30% of consultations and in a further 47 patients (5%), the diagnosis was proposed by the ICS on initial consultation.(ABSTRACT TRUNCATED AT 250 WORDS)

A case of infection involving a prosthetic joint in a patient with adult Still's Disease is described. The causative organism was a strain of Bacteroides fragilis which was resistant to metronidazole. The rarity of this occurrence is emphasised. Diagnostic difficulties which arose are described and the problems encountered with therapy discussed.

A two part study was undertaken to evaluate the effectiveness of an educational protocol and consult service on parenteral nutrition (PN) utilization. Forty-one patient admissions were evaluated retrospectively and nine prospectively. Average length of hospital stay and number of days on PN were decreased significantly (p less than .05). Frequency of adverse effects were also decreased significantly (p less than .05). A positive trend toward selection of patients for enteral rather than PN was evidenced. Utilization of already available manpower and financial resources by this modified approach should contribute toward reducing costs and hazards of PN therapy, particularly for smaller hospitals with both limited requirements and resources, as well as for teaching institutions.