We investigated the role of maternal antibody in neonatal Group B streptococcal infection with a radioactive antigen-binding assay employing a purified polysaccharide antigen with both Type III and Group B determinants. Serums from seven women who gave birth to infants who had invasive Group B streptococcal infection with Type III strains were all deficient in antibody. In contrast, serums from 22 of 29 pregnant Type III vaginal carriers whose infants were healthy contained antibody with a prevalence significantly different from that in women delivering infants with Type III disease (P less than 0.01). Three healthy neonates born to women with antibody in serums had demonstrable antibody in umbilical-cord serum. These data suggest that transplacental transfer of maternal antibody protects infants from invasive Group B streptococcal infection with Type III strains.

Small cell lung cancer (SCLC) is a highly aggressive human tumor with a more than 95% mortality rate. Its ontogeny and molecular pathogenesis remains poorly understood. We established a mouse model for neuroendocrine (NE) lung tumors by conditional inactivation of Rb1 and Trp53 in mouse lung epithelial cells. Mice carrying conditional alleles for both Rb1 and Trp53 developed with high incidence aggressive lung tumors with striking morphologic and immunophenotypic similarities to SCLC. Most of these tumors, which we designate MSCLC (murine small cell lung carcinoma), diffusely spread through the lung and gave rise to extrapulmonary metastases. In our model, inactivation of both Rb1 and p53 was a prerequisite for the pathogenesis of SCLC.

The observation that CD45(+) stem cells injected into the circulation participate in muscle regeneration raised the question of whether CD45(+) stem cells resident in muscle play a physiological role during regeneration. We found that CD45(+) cells cultured from uninjured muscle were uniformly nonmyogenic. However, CD45(+) cells purified from regenerating muscle readily gave rise to determined myoblasts. The number of CD45(+) cells in muscle rapidly expanded following injury, and a high proportion entered the cell cycle. Investigation of candidate pathways involved in embryonic myogenesis revealed that Wnt signaling was sufficient to induce the myogenic specification of muscle-derived CD45(+) stem cells. Moreover, injection of the Wnt antagonists sFRP2/3 into regenerating muscle markedly reduced CD45(+) stem cell proliferation and myogenic specification. Our data therefore suggest that mobilization of resident CD45(+) stem cells is an important factor in regeneration after injury and highlight the Wnt pathway as a potential therapeutic target for degenerative neuromuscular disease.

Neurotrophic factors are agents with a promising ability to retard progression of neurodegenerative diseases and are effective in slowing photoreceptor degeneration in animal models of retinitis pigmentosa. Here we report a human clinical trial of a neurotrophic factor for retinal neurodegeneration. In this Phase I safety trial, human ciliary neurotrophic factor (CNTF) was delivered by cells transfected with the human CNTF gene and sequestered within capsules that were surgically implanted into the vitreous of the eye. The outer membrane of the encapsulated cell implant is semipermeable to allow CNTF to reach the retina. Ten participants received CNTF implants in one eye. When the implants were removed after 6 months, they contained viable cells with minimal cell loss and gave CNTF output at levels previously shown to be therapeutic for retinal degeneration in rcd1 dogs. Although the trial was not powered to form a judgment as to clinical efficacy, of seven eyes for which visual acuity could be tracked by conventional reading charts, three eyes reached and maintained improved acuities of 10-15 letters, equivalent to two- to three-line improvement on standard Snellen acuity charts. A surgically related choroidal detachment in one eye resulted in a transient acuity decrease that resolved with conservative management. This Phase I trial indicated that CNTF is safe for the human retina even with severely compromised photoreceptors. The approach to delivering therapeutic proteins to degenerating retinas using encapsulated cell implants may have application beyond disease caused by genetic mutations.

In the present study we searched for restriction fragment length polymorphisms (RFLP) in the human interleukin-1 beta (IL-1 beta) gene and for correlations to monocyte (Mo) function in non-related healthy donors and insulin-dependent diabetic patients. We demonstrated a diallelic polymorphism with the restriction enzyme TaqI consisting of fragments of 9.4 kb and 13.4 kb. No differences in allele or genotype frequencies of this RFLP were observed between randomly selected controls and randomly selected patients with insulin-dependent diabetes mellitus (IDDM). However, when analysing IDDM patients negative for HLA-DR3 and -DR4, our data demonstrate that the 13.4 kb allele is more frequent in this group compared to a matched control group. The functional impact of this RFLP was studied by analysing in vitro stimulated Mo IL-1 beta response. An IL-1 beta allele dosage effect on secretory capacity was observed after LPS-stimulation: 13.4/13.4 kb homozygous individuals secreted significantly more IL-1 beta than 9.4/13.4 kb heterozygous individuals, who secreted significantly more than 9.4/9.4 kb homozygous individuals. Analyses of supernatants from LPS-stimulated Mo cultures from individuals with each TaqI IL-1 beta genotype revealed no differences in the mouse thymocyte co-stimulatory assay when compared on a molar basis, indicating that the TaqI polymorphism gave rise only to quantitative differences in expression levels and probably not to a mutant IL-1 beta.(ABSTRACT TRUNCATED AT 250 WORDS)

Data from previous multiparameter fluorescence-activated cell sorter (FACS) analysis and sorting studies define a subset of murine B cells that expresses the Ly-1 surface determinant in conjunction with IgM, IgD, Ia, and other typical B cell markers. These Ly-1 B cells are physically and functionally distinct. They express more IgM and less IgD than most other B cells; they are not normally found in lymph node or bone marrow; they are always present at low frequencies (1-5%) in normal spleens, and, as we show here, they comprise about half of the B cells (10-20% of total cells) recovered from the peritoneal cavity in normal mice. Furthermore, most of the commonly studied IgM autoantibodies in normal and autoimmune mice are produced by these Ly-1 B cells, even though they seldom produce antibodies to exogenous antigens such as trinitrophenyl-Ficoll or trinitrophenyl-keyhole limpet hemocyanin. Cell transfer studies presented here demonstrate that the progenitors of Ly-1 B cells are different from the progenitors of the predominant B cell populations in spleen and lymph node. In these studies, we used FACS analysis and functional assays to characterize donor-derived (allotype-marked) B cells present in lethally irradiated recipients 1-2 mo after transfer. Surprisingly, adult bone marrow cells typically used to reconstitute B cells in irradiated recipients selectively failed to reconstitute the Ly-1 B subset. Liver, spleen, and bone marrow cells from young mice, in contrast, reconstituted all B cells (including Ly-1 B), and peritoneal "washout" cells (PerC) from adult mice uniquely reconstituted Ly-1 B. Bone marrow did not block Ly-1 B development, since PerC and newborn liver still gave rise to Ly-1 B when jointly transferred with marrow. These findings tentatively assign Ly-1 B to a distinct developmental lineage originating from progenitors that inhabit the same locations as other B cell progenitors in young animals, but move to unique location(s) in adults.

We studied the correlations between body mass index (BMI) and percent body fat (fat%) measured by dual-photon absorptiometry (DPA) in 445 white and 242 Asian adults aged 18-94 y. In addition, comparisons in six circumferences and eight skinfold-thickness measurements between whites and Asians were made to explain the discrepancies. Although Asians had lower BMI, they were fatter than whites of both sexes. The correlations between fat% and BMI varied by BMI and sex and race. Comparisons in anthropometry show that Asians had more subcutaneous fat than did whites and had different fat distributions from whites. Asians had more upper-body subcutaneous fat than did whites. The magnitude of differences between the two races was greater in females than in males. Prediction equations developed for each sex and race, based on BMI alone, gave SEEs ranging from 4.4% to 5.7%. All were significantly improved to the range of 3.5-4.4% when age and several skinfold-thickness measurements were added.

BACKGROUND

The first publication of this review in Issue 3, 2005 included studies up to November 2003. This update adds studies to December 2006 and focuses on application of a new method for meta-analysis of interrupted time series studies and application of new Cochrane Effective Practice and Organisation of Care (EPOC) Risk of Bias criteria to all studies in the review, including those studies in the previously published version. The aim of the review is to evaluate the impact of interventions from the perspective of antibiotic stewardship. The two objectives of antibiotic stewardship are first to ensure effective treatment for patients with bacterial infection and second support professionals and patients to reduce unnecessary use and minimize collateral damage.

OBJECTIVE

To estimate the effectiveness of professional interventions that, alone or in combination, are effective in antibiotic stewardship for hospital inpatients, to evaluate the impact of these interventions on reducing the incidence of antimicrobial-resistant pathogens or Clostridium difficile infection and their impact on clinical outcome.

METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE from 1980 to December 2006 and the EPOC specialized register in July 2007 and February 2009 and bibliographies of retrieved articles. The main comparison is between interventions that had a restrictive element and those that were purely persuasive. Restrictive interventions were implemented through restriction of the freedom of prescribers to select some antibiotics. Persuasive interventions used one or more of the following methods for changing professional behaviour: dissemination of educational resources, reminders, audit and feedback, or educational outreach. Restrictive interventions could contain persuasive elements.

METHODS

We included randomized clinical trials (RCTs), controlled clinical trials (CCT), controlled before-after (CBA) and interrupted time series studies (ITS). Interventions included any professional or structural interventions as defined by EPOC. The intervention had to include a component that aimed to improve antibiotic prescribing to hospital inpatients, either by increasing effective treatment or by reducing unnecessary treatment. The results had to include interpretable data about the effect of the intervention on antibiotic prescribing or microbial outcomes or relevant clinical outcomes.

METHODS

Two authors extracted data and assessed quality. We performed meta-regression of ITS studies to compare the results of persuasive and restrictive interventions. Persuasive interventions advised physicians about how to prescribe or gave them feedback about how they prescribed. Restrictive interventions put a limit on how they prescribed; for example, physicians had to have approval from an infection specialist in order to prescribe an antibiotic. We standardized the results of some ITS studies so that they are on the same scale (percent change in outcome), thereby facilitating comparisons of different interventions. To do this, we used the change in level and change in slope to estimate the effect size with increasing time after the intervention (one month, six months, one year, etc) as the percent change in level at each time point. We did not extrapolate beyond the end of data collection after the intervention. The meta-regression was performed using standard weighted linear regression with the standard errors of the coefficients adjusted where necessary.

RESULTS

For this update we included 89 studies that reported 95 interventions. Of the 89 studies, 56 were ITSs (of which 4 were controlled ITSs), 25 were RCT (of which 5 were cluster-RCTs), 5 were CBAs and 3 were CCTs (of which 1 was a cluster-CCT).Most (80/95, 84%) of the interventions targeted the antibiotic prescribed (choice of antibiotic, timing of first dose and route of administration). The remaining 15 interventions aimed to change exposure of patients to antibiotics by targeting the decision to treat or the duration of treatment. Reliable data about impact on antibiotic prescribing data were available for 76 interventions (44 persuasive, 24 restrictive and 8 structural). For the persuasive interventions, the median change in antibiotic prescribing was 42.3% for the ITSs, 31.6% for the controlled ITSs, 17.7% for the CBAs, 3.5% for the cluster-RCTs and 24.7% for the RCTs. The restrictive interventions had a median effect size of 34.7% for the ITSs, 17.1% for the CBAs and 40.5% for the RCTs. The structural interventions had a median effect of 13.3% for the RCTs and 23.6% for the cluster-RCTs. Data about impact on microbial outcomes were available for 21 interventions but only 6 of these also had reliable data about impact on antibiotic prescribing.Meta-analysis of 52 ITS studies was used to compare restrictive versus purely persuasive interventions. Restrictive interventions had significantly greater impact on prescribing outcomes at one month (32%, 95% confidence interval (CI) 2% to 61%, P = 0.03) and on microbial outcomes at 6 months (53%, 95% CI 31% to 75%, P = 0.001) but there were no significant differences at 12 or 24 months. Interventions intended to decrease excessive prescribing were associated with reduction in Clostridium difficile infections and colonization or infection with aminoglycoside- or cephalosporin-resistant gram-negative bacteria, methicillin-resistant Staphylococcus aureus and vancomycin-resistant Enterococcus faecalis. Meta-analysis of clinical outcomes showed that four interventions intended to increase effective prescribing for pneumonia were associated with significant reduction in mortality (risk ratio 0.89, 95% CI 0.82 to 0.97), whereas nine interventions intended to decrease excessive prescribing were not associated with significant increase in mortality (risk ratio 0.92, 95% CI 0.81 to 1.06).

CONCLUSIONS

The results show that interventions to reduce excessive antibiotic prescribing to hospital inpatients can reduce antimicrobial resistance or hospital-acquired infections, and interventions to increase effective prescribing can improve clinical outcome. This update provides more evidence about unintended clinical consequences of interventions and about the effect of interventions to reduce exposure of patients to antibiotics. The meta-analysis supports the use of restrictive interventions when the need is urgent, but suggests that persuasive and restrictive interventions are equally effective after six months.

High-throughput technologies have revolutionized medical research. The advent of genotyping arrays enabled large-scale genome-wide association studies and methods for examining global transcript levels, which gave rise to the field of "integrative genetics". Other omics technologies, such as proteomics and metabolomics, are now often incorporated into the everyday methodology of biological researchers. In this review, we provide an overview of such omics technologies and focus on methods for their integration across multiple omics layers. As compared to studies of a single omics type, multi-omics offers the opportunity to understand the flow of information that underlies disease.

A plasmid including a mouse immunoglobulin mu gene was transfected into the IgG-secreting human lymphoid line HMy2 and mouse B- and pre-B-cell lines WEHI 231 and 18-81; stably transfected cells were selected. Transfected HMy2 cells synthesized mouse immunoglobulin mu chains as a major secreted protein but the WEHI 231 and 18-81 transfectants transcribed the introduced mu gene at lower levels. In HMy2 transfectants, most of the transcription of the introduced heavy chain gene initiated 40 and 62 bp upstream of the beginning of the VH exon translation start, although a small proportion of transcripts initiating further upstream was detected. WEHI 231 and 18-81 transfectants gave a much higher proportion of upstream initiation. Transient expression of the VH exon was monitored following transfection of mouse myeloma with the VH gene DNA in various plasmid constructs. VH transcription was only observed if the plasmids contained a segment derived from the large VH-CH intron of the immunoglobulin heavy chain locus. This segment, located between JH and switch regions, functioned both downstream of the VH exon and upstream in either orientation. The existence of a transcription enhancer element in this region is therefore proposed.

Hair cells of the guinea pig cochlea were preserved for electron microscopic examination by fixing in glutaraldehyde without the use of osmium. An extensive array of cross-links was seen between the stereocilia, by both scanning and transmission electron microscopy. The stereocilia were linked together laterally, particularly near their apical ends, by links running approximately at right angles to the long axis of the stereocilia. One set joined stereocilia of the same row, and another set joined stereocilia of the different rows, holding the tips of the shorter stereocilia in towards the longer stereocilia of the next row. In addition, the tip of each shorter stereocilium on the hair cell gave rise to a single, upwards-pointing link, which ran up to join the taller stereocilium of the next row. We suggest that distortion of this link would give rise to sensory transduction. On this basis, we are able to explain the V shape of the rows of stereocilia on outer hair cells. Within the rows, the three-dimensional arrangement of the stereocilia was different from that seen conventionally. Rather than standing parallel, the stereocilia of the different rows tapered in together at the tips, presumably held by the laterally-running cross-links. In addition, a membrane roughness, particularly pronounced in the region of the stereocilium which gives rise to the cross-links, was seen. However, the lateral and basal surface membranes of the hair cell, and the membranes of the internal organelles, had a more conventional appearance.

The authors gave the Center for Epidemiologic Studies Depression (CES-D) Scale, a self-report depression symptom scale, to 528 subjects drawn from a larger longitudinal community survey. Interviewers also assessed respondents using the Schedule for Affective Disorders and Schizophrenia (SADS), a structured clinical interview; on the basis of the SADS the subjects were then given diagnoses according to the Research Diagnostic Criteria. The results corroborated earlier findings of a modest relationship between self-reported symptoms of depression and the diagnosis of depression. The authors conclude that the CES-D Scale may be useful as an initial or first-stage screening test.

Hair cells, the primary receptors of the auditory, vestibular, and lateral-line sensory systems, produce electrical signals in response to mechanical stimulation of their apical hair bundles. We employed an in vitro preparation and intracellular recording to investigate the transduction mechanism of hair cells in the sacculus from the inner ear of the bullfrog (Rana catesbeiana). When stimulated directly by mechanical deflection of their hair bundles, these cells gave graded responses up to 15 mV in amplitude; the peak sensitivity was about 20 mV/micron deflection. The depolarizing component of the receptor potential corresponding to stimuli directed towards the kinocilium. Depolarizing responses were associated with a membrane resistance decrease, and hyperpolarizing responses with a resistance increase. Action potentials, possibly calcium spikes, were occasionally evoked in hair cells by mechanical or electrical stimulation.

Many gram-negative bacteria regulate expression of specialized gene sets in response to population density. This regulatory mechanism, called autoinduction or quorum-sensing, is based on the production by the bacteria of a small, diffusible signal molecule called the autoinducer. In the most well-studied systems the autoinducers are N-acylated derivatives of L-homoserine lactone (acyl-HSL). Signal specificity is conferred by the length, and the nature of the substitution at C-3, of the acyl side-chain. We evaluated four acyl-HSL bioreporters, based on tra of Agrobacterium tumefaciens, lux of Vibrio fischeri, las of Pseudomonas aeruginosa, and pigment production by Chromobacterium violaceum, for their ability to detect sets of 3-oxo acyl-HSLs, 3-hydroxy acyl-HSLs, and alkanoyl-HSLs with chain lengths ranging from C4 to C12. The traG::lacZ fusion reporter from the A. tumefaciens Ti plasmid was the single most sensitive and versatile detector of the four. Using this reporter, we screened 106 isolates representing seven genera of bacteria that associate with plants. Most of the Agrobacterium, Rhizobium, and Pantoea isolates and about half of the Erwinia and Pseudomonas isolates gave positive reactions. Only a few isolates of Xanthomonas produced a detectable signal. We characterized the acyl-HSLs produced by a subset of the isolates by thin-layer chromatography. Among the pseudomonads and erwinias, most produced a single dominant activity chromatographing with the properties of N-(3-oxo-hexanoyl)-L-HSL. However, a few of the erwinias, and the P. fluorescens and Ralstonia solanacearum isolates, produced quite different signals, including 3-hydroxy forms, as well as active compounds that chromatographed with properties unlike any of our standards. The few positive xanthomonas, and almost all of the agrobacteria, produced small amounts of a compound with the chromatographic properties of N-(3-oxo-octanoyl)-L-HSL. Members of the genus Rhizobium showed the greatest diversity, with some producing as few as one and others producing as many as seven detectable signals. Several isolates produced extremely nonpolar compounds indicative of very long acyl side-chains. Production of these compounds suggests that quorum-sensing is common as a gene regulatory mechanism among gram-negative plant-associated bacteria.

A morbillivirus has been isolated and added to an increasing list of emerging viral diseases. This virus caused an outbreak of fatal respiratory disease in horses and humans. Genetic analyses show it to be only distantly related to the classic morbilliviruses rinderpest, measles, and canine distemper. When seen by electron microscopy, viruses had 10- and 18-nanometer surface projections that gave them a "double-fringed" appearance. The virus induced syncytia that developed in the endothelium of blood vessels, particularly the lungs.

Th17 cells have been described as short lived, but this view is at odds with their capacity to trigger protracted damage to normal and transformed tissues. We report that Th17 cells, despite displaying low expression of CD27 and other phenotypic markers of terminal differentiation, efficiently eradicated tumors and caused autoimmunity, were long lived, and maintained a core molecular signature resembling early memory CD8(+) cells with stem cell-like properties. In addition, we found that Th17 cells had high expression of Tcf7, a direct target of the Wnt and β-catenin signaling axis, and accumulated β-catenin, a feature observed in stem cells. In vivo, Th17 cells gave rise to Th1-like effector cell progeny and also self-renewed and persisted as IL-17A-secreting cells. Multipotency was required for Th17 cell-mediated tumor eradication because effector cells deficient in IFN-γ or IL-17A had impaired activity. Thus, Th17 cells are not always short lived and are a less-differentiated subset capable of superior persistence and functionality.

BACKGROUND

Erlotinib is registered for treatment of all patients with advanced non-small-cell lung cancer (NSCLC). However, its efficacy for treatment of patients whose tumours are EGFR wild-type-which includes most patients-is still contentious. We assessed the efficacy of erlotinib compared with a standard second-line chemotherapy in such patients.

METHODS

We did this randomised controlled trial in 52 Italian hospitals. We enrolled patients who had metastatic NSCLC, had had platinum-based chemotherapy, and had wild-type EGFR as assessed by direct sequencing. Patients were randomly assigned centrally (1:1) to receive either erlotinib orally 150 mg/day or docetaxel intravenously 75 mg/m(2) every 21 days or 35 mg/m(2) on days 1, 8, and 15, every 28 days. Randomisation was stratified by centre, stage, type of first-line chemotherapy, and performance status. Patients and investigators who gave treatments or assessed outcomes were not masked to treatment allocation, investigators who analysed results were. The primary endpoint was overall survival in the intention-to-treat population. The study is registered at ClinicalTrials.gov, number NCT00637910.

RESULTS

We screened 702 patients, of whom we genotyped 540. 222 patients were enrolled (110 assigned to docetaxel vs 112 assigned to erlotinib). Median overall survival was 8·2 months (95% CI 5·8-10·9) with docetaxel versus 5·4 months (4·5-6·8) with erlotinib (adjusted hazard ratio [HR] 0·73, 95% CI 0·53-1·00; p=0·05). Progression-free survival was significantly better with docetaxel than with erlotinib: median progression-free survival was 2·9 months (95% CI 2·4-3·8) with docetaxel versus 2·4 months (2·1-2·6) with erlotinib (adjusted HR 0·71, 95% CI 0·53-0·95; p=0·02). The most common grade 3-4 toxic effects were: low absolute neutrophil count (21 [20%] of 104 in the docetaxel group vs none of 107 in the erlotinib group), skin toxic effects (none vs 15 [14%]), and asthenia (ten [10%] vs six [6%]).

CONCLUSIONS

Our results show that chemotherapy is more effective than erlotinib for second-line treatment for previously treated patients with NSCLC who have wild-type EGFR tumours.

Potent sequence selective gene inhibition by siRNA 'targeted' therapeutics promises the ultimate level of specificity, but siRNA therapeutics is hindered by poor intracellular uptake, limited blood stability and non-specific immune stimulation. To address these problems, ligand-targeted, sterically stabilized nanoparticles have been adapted for siRNA. Self-assembling nanoparticles with siRNA were constructed with polyethyleneimine (PEI) that is PEGylated with an Arg-Gly-Asp (RGD) peptide ligand attached at the distal end of the polyethylene glycol (PEG), as a means to target tumor neovasculature expressing integrins and used to deliver siRNA inhibiting vascular endothelial growth factor receptor-2 (VEGF R2) expression and thereby tumor angiogenesis. Cell delivery and activity of PEGylated PEI was found to be siRNA sequence specific and depend on the presence of peptide ligand and could be competed by free peptide. Intravenous administration into tumor-bearing mice gave selective tumor uptake, siRNA sequence-specific inhibition of protein expression within the tumor and inhibition of both tumor angiogenesis and growth rate. The results suggest achievement of two levels of targeting: tumor tissue selective delivery via the nanoparticle ligand and gene pathway selectivity via the siRNA oligonucleotide. This opens the door for better targeted therapeutics with both tissue and gene selectivity, also to improve targeted therapies with less than ideal therapeutic targets.

Tetherin (CD317/BST-2), an interferon-induced membrane protein, restricts the release of nascent retroviral particles from infected cell surfaces. While human immunodeficiency virus type 1 (HIV-1) encodes the accessory gene vpu to overcome the action of tetherin, the lineage of primate lentiviruses that gave rise to HIV-2 does not. It has been previously reported that the HIV-2 envelope glycoprotein has a Vpu-like function in promoting virus release. Here we demonstrate that the HIV-2 Rod envelope glycoprotein (HIV-2 Rod Env) is a tetherin antagonist. Expression of HIV-2 Rod Env, but not that of HIV-1 or the closely related simian immunodeficiency virus (SIV) SIVmac1A11, counteracts tetherin-mediated restriction of Vpu-defective HIV-1 in a cell-type-specific manner. This correlates with the ability of the HIV-2 Rod Env to mediate cell surface downregulation of tetherin. Antagonism requires an endocytic motif conserved across HIV/SIV lineages in the gp41 cytoplasmic tail, but specificity for tetherin is governed by extracellular determinants in the mature Env protein. Coimmunoprecipitation studies suggest an interaction between HIV-2 Rod Env and tetherin, but unlike studies with Vpu, we found no evidence of tetherin degradation. In the presence of HIV-2 Rod Env, tetherin localization is restricted to the trans-Golgi network, suggesting Env-mediated effects on tetherin trafficking sequester it from virus assembly sites on the plasma membrane. Finally, we recapitulated these observations in HIV-2-infected CD4+ T-cell lines, demonstrating that tetherin antagonism and sequestration occur at physiological levels of Env expression during virus replication.

Although some viruses, particularly the herpes viruses, may never be eliminated from the body, others like influenza A, regularly reinfect humans and boost waning crossreactive CD8+ T-cell immunity. Prolonged T-cell memory is found for viruses that are unlikely to be re-encountered and which do not persist in the host genome, indicating that CD8+ T-cell memory might be independent of continued (or sporadic) antigenic exposure. A feature of virus-specific CD8+ T-cell memory is that antigen-specific cytotoxic T-lymphocyte precursors (CTLp) are greatly increased and remain high throughout life. The idea that persistence of the inducing antigen is essential is based on experiments in which adoptively transferred CD8+ memory T cells could not be detected for more than a few weeks in naive recipient mice without secondary challenge. Here we show that restimulation of such chimaeric mice with an inducing Sendai virus antigen increases the clonal burst size more than 7-fold within 8 days, making memory CTLp easier to detect in the longer term. We find that Sendai-virus-specific CTLp are maintained for>> 250 days in irradiated uninfected recipients, including reconstituted beta 2-microglobulin-/- mice. To determine whether a source of viral peptide can persist after primary infection, we gave Sendai-virus-specific Thy1.1+ memory spleen cells to naive mice that had been minimally depleted of Thy1.2+ T cells, or to comparable recipients that had recovered from infection with Sendai virus or influenza virus. Although antibody against Sendai virus was never found in the naive recipients, Sendai-virus-specific CD8+ memory T cells were maintained equally well in each case for>> 100 days after cell transfer. We find no evidence for persisting depots of viral protein that might feed into the endogenous processing pathway and maintain virus-specific CD8+ T-cell memory.

A large outbreak of haemorrhagic fever (subsequently named Ebola haemorrhagic fever) occurred in southern Sudan between June and November 1976. There was a total of 284 cases; 67 in the source town of Nzara, 213 in Maridi, 3 in Tembura, and 1 in Juba. The outbreak in Nzara appears to have originated in the workers of a cotton factory. The disease in Maridi was amplified by transmission in a large, active hospital. Transmission of the disease required close contact with an acute case and was usually associated with the act of nursing a patient. The incubation period was between 7 and 14 days. Although the link was not well established, it appears that Nzara could have been the source of infection for a similar outbreak in the Bumba Zone of Zaire.In this outbreak Ebola haemorrhagic fever was a unique clinical disease with a high mortality rate (53% overall) and a prolonged recovery period in those who survived. Beginning with an influenza-like syndrome, including fever, headache, and joint and muscle pains, the disease soon caused diarrhoea (81%), vomiting (59%), chest pain (83%), pain and dryness of the throat (63%), and rash (52%). Haemorrhagic manifestations were common (71%), being present in half of the recovered cases and in almost all the fatal cases.Two post mortems were carried out on patients in November 1976. The histopathological findings resembled those of an acute viral infection and although the features were characteristic they were not exclusively diagnostic. They closely resembled the features described in Marburg virus infection, with focal eosinophilic necrosis in the liver and destruction of lymphocytes and their replacement by plasma cells. One case had evidence of renal tubular necrosis.Two strains of Ebola virus were isolated from acute phase sera collected from acutely ill patients in Maridi hospital during the investigation in November 1976. Antibodies to Ebola virus were detected by immunofluorescence in 42 of 48 patients in Maridi who had been diagnosed clinically, but in only 6 of 31 patients in Nzara. The possibility of the indirect immunofluorescent test not being sufficiently sensitive is discussed.Of Maridi case contacts, in hospital and in the local community, 19% had antibodies. Very few of them gave any history of illness, indicating that Ebola virus can cause mild or even subclinical infections. Of the cloth room workers in the Nzara cotton factory, 37% appeared to have been infected, suggesting that the factory may have been the prime source of infection.

We present an Aboriginal Australian genomic sequence obtained from a 100-year-old lock of hair donated by an Aboriginal man from southern Western Australia in the early 20th century. We detect no evidence of European admixture and estimate contamination levels to be below 0.5%. We show that Aboriginal Australians are descendants of an early human dispersal into eastern Asia, possibly 62,000 to 75,000 years ago. This dispersal is separate from the one that gave rise to modern Asians 25,000 to 38,000 years ago. We also find evidence of gene flow between populations of the two dispersal waves prior to the divergence of Native Americans from modern Asian ancestors. Our findings support the hypothesis that present-day Aboriginal Australians descend from the earliest humans to occupy Australia, likely representing one of the oldest continuous populations outside Africa.

Twenty-nine drugs of disparate structures and physicochemical properties were used in an examination of the capability of human liver microsomal lability data ("in vitro T(1/2)" approach) to be useful in the prediction of human clearance. Additionally, the potential importance of nonspecific binding to microsomes in the in vitro incubation milieu for the accurate prediction of human clearance was investigated. The compounds examined demonstrated a wide range of microsomal metabolic labilities with scaled intrinsic clearance values ranging from less than 0.5 ml/min/kg to 189 ml/min/kg. Microsomal binding was determined at microsomal protein concentrations used in the lability incubations. For the 29 compounds studied, unbound fractions in microsomes ranged from 0.11 to 1.0. Generally, basic compounds demonstrated the greatest extent of binding and neutral and acidic compounds the least extent of binding. In the projection of human clearance values, basic and neutral compounds were well predicted when all binding considerations (blood and microsome) were disregarded, however, including both binding considerations also yielded reasonable predictions. Including only blood binding yielded very poor projections of human clearance for these two types of compounds. However, for acidic compounds, disregarding all binding considerations yielded poor predictions of human clearance. It was generally most difficult to accurately predict clearance for this class of compounds; however the accuracy was best when all binding considerations were included. Overall, inclusion of both blood and microsome binding values gave the best agreement between in vivo clearance values and clearance values projected from in vitro intrinsic clearance data.

OBJECTIVE

To determine whether hospitals with a good organisation of care (such as improved nurse staffing and work environments) can affect patient care and nurse workforce stability in European countries.

METHODS

Cross sectional surveys of patients and nurses.

METHODS

Nurses were surveyed in general acute care hospitals (488 in 12 European countries; 617 in the United States); patients were surveyed in 210 European hospitals and 430 US hospitals.

METHODS

33 659 nurses and 11 318 patients in Europe; 27 509 nurses and more than 120 000 patients in the US.

METHODS

Nurse outcomes (hospital staffing, work environments, burnout, dissatisfaction, intention to leave job in the next year, patient safety, quality of care), patient outcomes (satisfaction overall and with nursing care, willingness to recommend hospitals).

RESULTS

The percentage of nurses reporting poor or fair quality of patient care varied substantially by country (from 11% (Ireland) to 47% (Greece)), as did rates for nurses who gave their hospital a poor or failing safety grade (4% (Switzerland) to 18% (Poland)). We found high rates of nurse burnout (10% (Netherlands) to 78% (Greece)), job dissatisfaction (11% (Netherlands) to 56% (Greece)), and intention to leave (14% (US) to 49% (Finland, Greece)). Patients' high ratings of their hospitals also varied considerably (35% (Spain) to 61% (Finland, Ireland)), as did rates of patients willing to recommend their hospital (53% (Greece) to 78% (Switzerland)). Improved work environments and reduced ratios of patients to nurses were associated with increased care quality and patient satisfaction. In European hospitals, after adjusting for hospital and nurse characteristics, nurses with better work environments were half as likely to report poor or fair care quality (adjusted odds ratio 0.56, 95% confidence interval 0.51 to 0.61) and give their hospitals poor or failing grades on patient safety (0.50, 0.44 to 0.56). Each additional patient per nurse increased the odds of nurses reporting poor or fair quality care (1.11, 1.07 to 1.15) and poor or failing safety grades (1.10, 1.05 to 1.16). Patients in hospitals with better work environments were more likely to rate their hospital highly (1.16, 1.03 to 1.32) and recommend their hospitals (1.20, 1.05 to 1.37), whereas those with higher ratios of patients to nurses were less likely to rate them highly (0.94, 0.91 to 0.97) or recommend them (0.95, 0.91 to 0.98). Results were similar in the US. Nurses and patients agreed on which hospitals provided good care and could be recommended.

CONCLUSIONS

Deficits in hospital care quality were common in all countries. Improvement of hospital work environments might be a relatively low cost strategy to improve safety and quality in hospital care and to increase patient satisfaction.