Occurrence and a possible mechanism of penetration of natural killer cells into k562 target cells during the cytotoxic interaction

The cytotoxic interaction between cloned human Natural Killer (NK) cells and K562 target cells was studied using confocal laser scanning microscopy (CLSM) and conventional fluorescence microscopy. We observed, using fixed as well as living cells, the occurrence of (pseudo)emperipolesis during the interaction. About 30% of conjugated NK cells penetrated, partly or completely, into the target cells (in-conjugation). Virtually all in-conjugated target cells exhibited polymerized actin. Killer cells of in-conjugates were frequently seen approaching the target cell nucleus or aligning along it. If the cytotoxic process was inhibited by the absence of calcium neither actin polymerization nor in-conjugation were observed. A kinetic study showed that in-conjugation starts somewhat later than actin polymerization but still within a few minutes after addition of calcium to conjugates previously formed in the absence of calcium. The presence of cytochalasin D (an inhibitor of actin polymerization) completely inhibited in-conjugation and partly reduced the cytotoxic activity. Zinc ions (endonuclease inhibition) inhibited in-conjugation and decreased the total number of target cells with polymerized actin in a concentration dependent manner. Cytotoxic activity was also reduced but not as efficiently as in-conjugation. \ud Our study demonstrates that in-conjugation represents a significant fraction of the cytotoxic interaction. The results indicate that it may be a consequence of an actin polymerization and endonuclease activity dependent part of a cytotoxic mechanism. \u

Production and characterization of monoclonal antibodies raised against recombinant human granzymes A and B and showing cross reactions with the natural proteins

The human serine proteases granzymes A and B are expressed in cytotoplasmic granules of activated cytotoxic T lymphocytes and natural killer cells. Recombinant granzyme A and granzyme B proteins were produced in bacteria, purified and then used to raise specific mouse monoclonal antibodies. Seven monoclonal antibodies (mAb) were raised against granzyme A, which all recognized the same or overlapping epitopes. They reacted specifically in an immunoblot of interleukin-2 (IL-2) stimulated PBMNC with a disulfide-linked homodimer of 43 kDa consisting of 28 kDa subunits. Seven mAb against granzyme B were obtained, which could be divided into two groups, each recognizing a different epitope. On an immunoblot, all mAb reacted with a monomer of 33 kDa protein. By immunohistochemistry, these mAb could be used to detect granzymes A and B expression in activated CTL and NK cells. The availability of these mAb may facilitate studies on the role of human cytotoxic cells in various immune reactions and may contribute to a better understanding of the role of granzmes A and B in the cytotoxic response in vivo

High precision astrometry mission for the detection and characterization of nearby habitable planetary systems with the Nearby Earth Astrometric Telescope (NEAT)

(abridged) A complete census of planetary systems around a volume-limited sample of solar-type stars (FGK dwarfs) in the Solar neighborhood with uniform sensitivity down to Earth-mass planets within their Habitable Zones out to several AUs would be a major milestone in extrasolar planets astrophysics. This fundamental goal can be achieved with a mission concept such as NEAT - the Nearby Earth Astrometric Telescope. NEAT is designed to carry out space-borne extremely-high-precision astrometric measurements sufficient to detect dynamical effects due to orbiting planets of mass even lower than Earth's around the nearest stars. Such a survey mission would provide the actual planetary masses and the full orbital geometry for all the components of the detected planetary systems down to the Earth-mass limit. The NEAT performance limits can be achieved by carrying out differential astrometry between the targets and a set of suitable reference stars in the field. The NEAT instrument design consists of an off-axis parabola single-mirror telescope, a detector with a large field of view made of small movable CCDs located around a fixed central CCD, and an interferometric calibration system originating from metrology fibers located at the primary mirror. The proposed mission architecture relies on the use of two satellites operating at L2 for 5 years, flying in formation and offering a capability of more than 20,000 reconfigurations (alternative option uses deployable boom). The NEAT primary science program will encompass an astrometric survey of our 200 closest F-, G- and K-type stellar neighbors, with an average of 50 visits. The remaining time might be allocated to improve the characterization of the architecture of selected planetary systems around nearby targets of specific interest (low-mass stars, young stars, etc.) discovered by Gaia, ground-based high-precision radial-velocity surveys.Comment: Accepted for publication in Experimental Astronomy. The full member list of the NEAT proposal and the news about the project are available at http://neat.obs.ujf-grenoble.fr. The final publication is available at http://www.springerlink.co

Cost-Effective and Sustainable Drug Use in Hospitals:A Systematic and Practice-Based Approach

Background and Objective: Rising healthcare costs challenge the financial sustainability of healthcare systems. Interventional pharmacoeconomics has emerged as a vital discipline to improve the cost-effective and sustainable use of drugs in clinical practice. However, current efforts are often fragmented, highlighting the need for an integrated hospital-wide approach. This study aimed to develop a scalable framework to systematically identify and implement cost-effective and sustainable drug use practices in hospitals. Methods: This study was conducted at the Erasmus University Medical Centre in Rotterdam between December 2022 and July 2023. A novel ‘8-Step Efficiency Model’ was designed to systematically identify and evaluate strategies for cost-effective and sustainable drug use. The process involved identifying high-expenditure drugs, systematically assessing these drugs using the Efficiency Model, and conducting a multi-disciplinary evaluation of the proposed cost-effectiveness strategies. Results: The study assessed 39 high-cost drugs, representing 57% of the Dutch national expensive drug expenditure in 2021. Initiatives for enhancing cost-effectiveness and sustainability were identified or developed for 27 out of the 39 assessed drugs (51% of the national drug expenditure in 2021). Case examples of infliximab (e.g., wastage prevention) and intravenous immunoglobulins (e.g., lean body weight dosing) illustrate practical applications of the framework, resulting in substantial cost savings and improved sustainability. Conclusions: This study presents a systematic scalable model for enhancing the cost-effectiveness of high-expenditure drugs in hospital settings. This approach not only addresses financial sustainability but also promotes the quality of patient care and sustainable drug use. This model could serve as a generic blueprint for other institutions to identify and implement cost-effective and sustainable drug use strategies.</p

Selective decontamination of the digestive tract: all questions answered?

Although many studies have shown beneficial effects of SDD on the incidence of respiratory tract infections, SDD did not become routine practice because mortality reduction was not demonstrated in individual trials, beneficial effects on duration of ventilation, ICU stay or hospital stay were not demonstrated, cost-efficacy had not been demonstrated, and selection of antibiotic resistance was considered a serious side-effect. A recent study has now shown improved patient survival and lower prevalence of antibiotic resistance in patients receiving SDD. Why could this study show mortality reduction, where all others studies had failed before? And do the microbiological data unequivocally prove protective effects of SDD on emergence of antibiotic resistance? Interestingly, the reported mortality reductions exceeds even the most optimistic predictions from previous meta-analyses, but a clear explanation is not yet evident. The data on antibiotic resistance, however, are rather superficial and do not allow to interpret the underlying epidemiological dynamics. Therefore, the recent findings are provocative and shed new light on the SDD issue, warranting studies confirming its beneficial effects but also addressing several important aspects related to study design

Functional mechanisms underlying pleiotropic risk alleles at the 19p13.1 breast-ovarian cancer susceptibility locus

A locus at 19p13 is associated with breast cancer (BC) and ovarian cancer (OC) risk. Here we analyse 438 SNPs in this region in 46,451 BC and 15,438 OC cases, 15,252 BRCA1 mutation carriers and 73,444 controls and identify 13 candidate causal SNPs associated with serous OC (P=9.2 × 10-20), ER-negative BC (P=1.1 × 10-13), BRCA1-associated BC (P=7.7 × 10-16) and triple negative BC (P-diff=2 × 10-5). Genotype-gene expression associations are identified for candidate target genes ANKLE1 (P=2 × 10-3) and ABHD8 (P<2 × 10-3). Chromosome conformation capture identifies interactions between four candidate SNPs and ABHD8, and luciferase assays indicate six risk alleles increased transactivation of the ADHD8 promoter. Targeted deletion of a region containing risk SNP rs56069439 in a putative enhancer induces ANKLE1 downregulation; and mRNA stability assays indicate functional effects for an ANKLE1 3′-UTR SNP. Altogether, these data suggest that multiple SNPs at 19p13 regulate ABHD8 and perhaps ANKLE1 expression, and indicate common mechanisms underlying breast and ovarian cancer risk

Surgical outcomes in surgical oncology patients who participated in a family involvement program

BACKGROUND: There is a lack of evidence regarding the relationship between family involvement and outcomes in gastrointestinal oncology patients after surgery. To evaluate the effect of a family involvement program for patients undergoing oncologic gastrointestinal surgery on unplanned readmissions within 30 days after surgery.METHODS: A multicenter patient-preference cohort study compared 2 groups: patients who participated in the family involvement program versus usual care. The program comprised involvement of family caregivers in care and training of health care professionals in family-centered care. Multivariable regression analyses were used to evaluate the effect of the FIP on the number of unplanned readmissions up to 30 days after surgery. Secondary outcomes included complications sensitive to fundamental care activities, emergency department visits, intensive care unit admissions, hospital length of stay, and the need for professional home care after discharge.RESULTS: Of the 301 patients included, 152 chose the family involvement program, and 149 chose usual care. Postoperative readmissions occurred in 25 (16.4%) patients in the family involvement program group, and 15 (10.1%) in the usual care group (P = .11). A significant reduction of 16.2% was observed in the need for professional home care after discharge in the family involvement program group (P &lt; .01). No significant differences were found between the 2 groups in the other secondary outcomes.CONCLUSION: The family involvement program did not reduce the number of unplanned readmissions, but it led to a substantial reduction in-home care, which suggests an economic benefit from a societal perspective. Implementation of the family involvement program should, therefore, be considered in clinical practice.</p

Surgical outcomes in surgical oncology patients who participated in a family involvement program

BACKGROUND: There is a lack of evidence regarding the relationship between family involvement and outcomes in gastrointestinal oncology patients after surgery. To evaluate the effect of a family involvement program for patients undergoing oncologic gastrointestinal surgery on unplanned readmissions within 30 days after surgery.METHODS: A multicenter patient-preference cohort study compared 2 groups: patients who participated in the family involvement program versus usual care. The program comprised involvement of family caregivers in care and training of health care professionals in family-centered care. Multivariable regression analyses were used to evaluate the effect of the FIP on the number of unplanned readmissions up to 30 days after surgery. Secondary outcomes included complications sensitive to fundamental care activities, emergency department visits, intensive care unit admissions, hospital length of stay, and the need for professional home care after discharge.RESULTS: Of the 301 patients included, 152 chose the family involvement program, and 149 chose usual care. Postoperative readmissions occurred in 25 (16.4%) patients in the family involvement program group, and 15 (10.1%) in the usual care group (P = .11). A significant reduction of 16.2% was observed in the need for professional home care after discharge in the family involvement program group (P &lt; .01). No significant differences were found between the 2 groups in the other secondary outcomes.CONCLUSION: The family involvement program did not reduce the number of unplanned readmissions, but it led to a substantial reduction in-home care, which suggests an economic benefit from a societal perspective. Implementation of the family involvement program should, therefore, be considered in clinical practice.</p

Alu-repeat–induced deletions within the NCF2 gene causing p67- phox –deficient chronic granulomatous disease (CGD)

Mutations that impair expression or function of the components of the phagocyte NADPH oxidase complex cause chronic granulomatous disease (CGD), which is associated with life-threatening infections and dysregulated granulomatous inflammation. In five CGD patients from four consanguineous families of two different ethnic backgrounds, we found similar genomic homozygous deletions of 1,380 bp comprising exon 5 of NCF2 , which could be traced to Alu-mediated recombination events. cDNA sequencing showed in-frame deletions of phase zero exon 5, which encodes one of the tandem repeat motifs in the tetratricopeptide (TPR4) domain of p67- phox . The resulting shortened protein (p67Δ5) had a 10-fold reduced intracellular half-life and was unable to form a functional NADPH oxidase complex. No dominant negative inhibition of oxidase activity by p67Δ5 was observed. We conclude that Alu-induced deletion of the TPR4 domain of p67- phox leads to loss of function and accelerated degradation of the protein, and thus represents a new mechanism causing p67- phox –deficient CGD. Hum Mutat 30:1–8, 2009. © 2009 Wiley-Liss, Inc.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/64904/1/21156_ftp.pd

Genome-Wide Association Study in BRCA1 Mutation Carriers Identifies Novel Loci Associated with Breast and Ovarian Cancer Risk

BRCA1-associated breast and ovarian cancer risks can be modified by common genetic variants. To identify further cancer risk-modifying loci, we performed a multi-stage GWAS of 11,705 BRCA1 carriers (of whom 5,920 were diagnosed with breast and 1,839 were diagnosed with ovarian cancer), with a further replication in an additional sample of 2,646 BRCA1 carriers. We identified a novel breast cancer risk modifier locus at 1q32 for BRCA1 carriers (rs2290854, P = 2.7×10-8, HR = 1.14, 95% CI: 1.09-1.20). In addition, we identified two novel ovarian cancer risk modifier loci: 17q21.31 (rs17631303, P = 1.4×10-8, HR = 1.27, 95% CI: 1.17-1.38) and 4q32.3 (rs4691139, P = 3.4×10-8, HR = 1.20, 95% CI: 1.17-1.38). The 4q32.3 locus was not associated with ovarian cancer risk in the general population or BRCA2 carriers, suggesting a BRCA1-specific associat