Experiences of nursing students participating in end-of-life education programs: A systematic review and qualitative metasynthesis.

OBJECTIVE: The aim of this review was to explore the experiences of nursing students participating in end-of-life education programs. DESIGN: A systematic review. DATA SOURCES: Exhaustive literature searches were performed using seven electronic databases: Medline, Scopus, Web of Science, CINAHL Plus, Dialnet Plus, Eric and Cuiden Plus. REVIEW METHODS: In total, 6572 studies published from 2008 until 2018 were examined. The Critical Appraisal Skills Program was used to assess the quality of the studies included in the review. The findings were synthesized using meta-aggregation. RESULTS: Seventeen studies were included in this systematic review, representing a sample of 606 nursing students. Simulation methods were most common among the educational programs analyzed. The analysis of qualitative data allowed us to identify 260 illustrations which were grouped into 14 categories and three themes: feelings and emotions during the performance of the pedagogical activity, end-of-life education among nursing students and competencies acquired on death and end-of-life. The most highlighted communication skills were learning to listen and building confidence to speak with the patient, family and the general public. CONCLUSIONS: End-of-life programs generally helped students acquire communication skills, learn concepts and improve the administration of this type of care. In addition, they perceived the experience as an opportunity to learn more about oneself, gain trust and support critical thinking. Nonetheless, the evidence available in this field is limited due to the small number of studies, plus the limited data reported. Thus, further studies on this subject are necessary.

Gene amplification-associated overexpression of the RNA editing enzyme ADAR1 enhances human lung tumorigenesis.

The introduction of new therapies against particular genetic mutations in non-small-cell lung cancer is a promising avenue for improving patient survival, but the target population is small. There is a need to discover new potential actionable genetic lesions, to which end, non-conventional cancer pathways, such as RNA editing, are worth exploring. Herein we show that the adenosine-to-inosine editing enzyme ADAR1 undergoes gene amplification in non-small cancer cell lines and primary tumors in association with higher levels of the corresponding mRNA and protein. From a growth and invasion standpoint, the depletion of ADAR1 expression in amplified cells reduces their tumorigenic potential in cell culture and mouse models, whereas its overexpression has the opposite effects. From a functional perspective, ADAR1 overexpression enhances the editing frequencies of target transcripts such as NEIL1 and miR-381. In the clinical setting, patients with early-stage lung cancer, but harboring ADAR1 gene amplification, have poor outcomes. Overall, our results indicate a role for ADAR1 as a lung cancer oncogene undergoing gene amplification-associated activation that affects downstream RNA editing patterns and patient prognosis.

DNA methylation determines nucleosome occupancy in the 5'-CpG islands of tumor suppressor genes.

Promoter CpG island hypermethylation of tumor suppressor genes is an epigenetic hallmark of human cancer commonly associated with nucleosome occupancy and the transcriptional silencing of the neighboring gene. Nucleosomes can determine the underlying DNA methylation status. Herein, we show that the opposite is also true: DNA methylation can determine nucleosome positioning. Using a cancer model and digital nucleosome positioning techniques, we demonstrate that the induction of DNA hypomethylation events by genetic (DNMT1/DNMT3B deficient cells) or drug (a DNA demethylating agent) approaches is associated with the eviction of nucleosomes from previously hypermethylated CpG islands of tumor suppressor genes. Most importantly, the establishment of a stable cell line that restores DNMT1/DNMT3B deficiency shows that nucleosomes reoccupy their positions in de novo methylated CpG islands. Finally, we extend these results to the genomic level, combining a DNA methylation microarray and the nucleosome positioning technique. Using this global approach, we observe the dependency of nucleosome occupancy upon the DNA methylation status. Thus, our results suggest that there is a close association between hypermethylated CpG islands and the presence of nucleosomes, such that each of these epigenetic mechanisms can determine the recruitment of the other.

Epigenetic inactivation of the ERK inhibitor Spry2 in B-cell diffuse lymphomas.

Spry2 has been characterized as a negative regulator of the extracellular-regulated kinase (ERK) pathway. In this study we analysed whether epigenetic alterations of hSpry2 promoter occur in human lymphoid/hematopoietic malignancies. Our results revealed that hSpry2 promoter was hypermethylated in the HT cell line derived from a B-cell diffuse lymphoma, which correlated with decreased hSpry2 expression. We detected deregulation of the ERK pathway in these cells, but not in other blood cell lines expressing hSpry2. In addition, the ectopic overexpression of hSpry2 in HT cells drastically reduced the activation of ERK upon phorbol 12-myristate-13-acetate stimulation. Nude mice inoculated with HT mock cells developed tumors seven times larger than those from HT-hSpry2-transfected cells. We found hypermethylation of hSpry2 promoter in 37% (26 cases out of 71) of primary tumors from patients with B-cell diffuse lymphoma but none in normal B lymphocytes from 37 healthy individuals. Finally, we detected that hSpry2 promoter hypermethylation was associated with a significant decrease in the 5-year survival rate. These data suggest that hSpry2 could be important in lymphoid malignancies.

Unmasking of epigenetically silenced candidate tumor suppressor genes by removal of methyl-CpG-binding domain proteins.

Methyl-cytosine-phosphate-guanine (CpG)-binding domain (MBD) proteins are bound to hypermethylated promoter CpG islands of tumor suppressor genes in human cancer cells, although a direct causal relationship at the genome-wide level between MBD presence and gene silencing remains to be demonstrated. To this end, we have inhibited the expression of MBD proteins in HeLa cells by short hairpin RNAs; and studied the functional consequences of MBD depletion using microarray-based expression analysis in conjunction with extensive bisulfite genomic sequencing and chromatin immunoprecipitation. The removal of MBDs results in a release of gene silencing associated with a loss of MBD occupancy in 5'-CpG islands without any change in the DNA methylation pattern. Our results unveil new targets for epigenetic inactivation mediated by MBDs in transformed cells, such as the cell adhesion protein gamma-parvin and the fibroblast growth factor 19, where we also demonstrate their bona fide tumor suppressor features. Our data support a fundamental role for MBD proteins in the direct maintenance of transcriptional repression of tumor suppressors and identify new candidate genes for epigenetic disruption in cancer cells.

Structural characterization of two CD1A allelic variants.

CD1 molecules are specialized in presenting lipidic antigens to T lymphocytes. They are structurally and evolutionary related to MHC molecules and show very limited polymorphism. We have previously described and partially characterized a new human CD1A allele differing from the wild type CD1A by a substitution of Cysteine by Tryptophan at position 52 in the alpha1 domain of the CD1A molecule. The frequency of this allele varies from 10% in individuals of Caucasian origin to 56% in Chinese people. The aim of the present work was to structurally characterize this CD1A allele. To do this we have cloned and sequenced the full-length cDNA encoding the new CD1A allele. The cDNA sequence of this allele encodes a protein differing the wild type in two amino acids at positions 14 (Threonine versus Isoleucine) and 52 (Cysteine versus Tryptophan). The cDNAs encoding both wild type and mutant CD1A were cloned in the expression vector pSRalphaNeo and transfected into C1R and L721.221 cells. Cell surface expression of the protein products in transfected cell lines were analyzed by flow cytometry and immunoprecipitation using CD1a-specific monoclonal antibodies. Our results indicate that both allelic products are efficiently expressed on the cell surface.

Characterization of the MHC class I-related MR1 locus in nonhuman primates.

We characterized the MHC-related 1 ( MR1) locus in two nonhuman primates species, Pongo pygmaeus and Pan troglodytes. MR1 cDNA sequences encoding several isoforms generated through alternative splicing were observed in both species. Amino acid alignment between the five species in which MR1 has been characterized to date - human, chimpanzee, orangutan, mouse, and rat - reveals a very high degree of conservation specially in the alpha1 and alpha2 domains of the molecule. The main differences concentrate in the transmembrane and cytoplasmic domains. In the three primates species there is a lysine residue inside the putative transmembrane domain which is not present in rodents. Furthermore, the MR1 cytoplasmic region is longer in rodents, with a conserved serine-containing motif that could be involved in endocytosis; remarkably, this motif is absent in the three primate species. We also describe the presence in the chimpanzee of a sequence homologous to the MR1P1 pseudogene previously found in humans.

A study on the polymorphism of human MHC class I-related MR1 gene and identification of an MR1-like pseudogene.

Human MR1 is a recently discovered, ubiquitously transcribed gene very similar to the HLA class I loci and of unknown function. Mouse and rat MR1 sequences have also been described showing high similarity with the human gene. The goal of this work was to investigate if human MR1 was polymorphic. We have found that DNA sequences of MR1-specific polymerase chain reaction (PCR) products obtained from samples of diverse ethnic origin were invariant except in one case in which two silent mutations were detected. We also found an MR1-like sequence displaying significant differences with the previously described, the most remarkable of which is a STOP codon in the alpha2 domain indicating that is a pseudogene.

Single strand conformational polymorphism analysis of human CD1 genes in different ethnic groups.

CD1 molecules are able to present unusual antigens, lipids or glycolipids from mycobacterium cell walls to T lymphocytes. Previous studies have suggested that polymorphism of these genes is very limited, in contrast with classical major histocompatibility complex (MHC) antigen-presenting molecules. Our aim was to study possible allelic variations of exons 2 and 3, encoding for the alpha1 and alpha2 domains, respectively, of human CD1A, -B, -C and -D genes. We analyzed genomic samples of unrelated, healthy individuals from different ethnic background: 70 Caucasians from Europe, 33 Black Africans (13 from Tanzania and 20 Zulus), 19 Caucasians from the Sahara and 44 Asian individuals. We have found CD1A to be a biallelic locus with a common allele which was present in the majority of the individuals studied. The second allele differed from the common one by a single-point mutation, resulting in a change of Cys to Trp at position 52 in the alpha1 domain. This second allele was found in heterozygosis in 7 out of 70 Caucasians from Europe (allelic frequencies P=0.95 and q=0.05). In the Chinese population, we found the second allele present in heterozygosis in 19 from the 44 individuals studied, and we also found 6 homozygous individuals for the second allele (allelic frequencies P=0.64 and q=0.35). In addition, we detected a synonymous mutation (C to T transition) in codon 34 of CD1C exon 2 in 4 out of 20 Zulus and in 2 of the 13 Blacks from Tanzania.

Molecular evolution of the N-formyl peptide and C5a receptors in non-human primates.

N-formyl peptides (FMLP) and complement fragment C5a are neutrophil chemoattractants. In humans, a single-copy gene was identified for the C5a receptor, and the receptor for FMLP (FPR1) is encoded by a single gene that shows 53% amino acid similarity to the C5aR. Two other human FPR1 homologues, FPR-like 1 (FPR2/FPRL1) and FPR-like 2 (FPRL2) have been cloned. The human C5aR, FPR1, FPRL1, and FPRL2 are physically linked. By direct sequencing or by sequencing plasmid clones we studied the C5aR and FPR genes from four non-human primates (chimpanzee, gorilla, orangutan, and macaque). The sequences showed 95% - 99% similarity to the human homologues, with the major divergences observed in macaque. In these genes, the transmembrane and the cytoplasmic domains are highly conserved, while the highest divergence corresponded to the extracellular loops involved in ligand binding. Additionally, we constructed a physical map of these genes in non-human primates. In all species the four genes were physically linked and we defined the relative orientation of the four genes in primates: C5aR>FPR1>FPR2 (FPRL1)>FPRL2.

Characterization of interleukin-8 receptors in non-human primates.

Interleukin-8 is a chemokine with a potent neutrophil chemoattractant activity. In humans, two different cDNAs encoding human IL8 receptors designated IL8RA and IL8RB have been cloned. IL8RA binds IL8, while IL8RB binds IL8 as well as other alpha-chemokines. Both human IL8Rs are encoded by two genes physically linked on chromosome 2. The IL8RA and IL8RB genes have open reading frames (ORF) lacking introns. By direct sequencing of the polymerase chain reaction products, we sequenced the IL8R genes of cell lines from four non-human primates: chimpanzee, gorilla, orangutan, and macaca. The IL8RB encodes an ORF in the four non-human primates, showing 95% - 99% similarity to the human IL8RB sequence. The IL8RA homologue in gorilla and chimpanzee consisted of two ORF 98% - 99% identical to the human sequence. The macaca and orangutan IL8RA homologues are pseudogenes: a 2 base pair insertion generated a sequence with several stop codons. In addition, we describe the physical linkage of these genes in the four non-human primates and discuss the evolutionary implications of these findings.

HLA-B27 subtypes in Asian patients with ankylosing spondylitis. Evidence for new associations.

The aim of this study was to investigate the contribution of the different B27 subtypes to ankylosing spondylitis (AS) susceptibility. The polymerase chain reaction (PCR) in combination with the sequence-specific oligonucleotide probes (SSOs) was used to analyse the polymorphism in exon 2 and 3 of HLA-B27 in two Asian groups with different genetic HLA structures: Indian (I) and Thai (T) populations. The same number of AS patients (45) and healthy B27 positive donors (n = 17) from both populations were analysed in order to ascertain the B27 subtypes. Three different findings can be concluded from this study: 1) B*2707 has been found to be associated with AS in both populations. This association has not been previously reported in either ethnic group. 2) B*2704 is strongly associated with AS in the Thai patients (91% in AS vs. 47% in C; RR = 11.5; EF = 0.83). In contrast, B*2704 was found with similar frequency in Asian Indians AS patients and controls (41% in AS vs. 41% in C.). 3) B*2706 was found overrepresented in control populations and absent in AS patients (0% in AS vs. 47% in C.; pc < 10(-6)) showing the maximum value of protective fraction (PF = 1). The B*2706 negative association with AS has not been previously described in other ethnic groups and could indicate a protective effect of this subtype on AS susceptibility. The B*2706 allele has two changes relative to B*2704 at residue 114 (His to Asp) and 116 (Asp to Tyr) in the pockets D/E. The importance that these differences can play in the pathogenesis of AS are discussed.

Genetic detection of the silent allele (*Q0) in hereditary deficiencies of the human complement C6, C7, and C9 components.

DNA polymorphisms (RFLPs) of the human complement component C6, C7, and C9 genes were studied in three C7-deficient (C7D) families, one C6-deficient (C6D) family, and one C9-deficient (C9D) family. The 3 loci are closely linked on human chromosome 5. The haplotypes carrying the "silent" allele (C7*Q0, C6*Q0, and C9*Q0) were defined in each family, allowing for the detection of carriers among asymptomatic relatives. This paper describes familial studies on a type of hereditary trait, characterized by recurrent Neisseria infections in individuals homozygous for "silent" alleles at the C6, C7, or C9 loci.

Combined (short-term plus longterm) sclerotherapy v short-term only sclerotherapy: a randomised prospective trial.

Short term sclerotherapy (by injection(s) around the bleeding point) is used for immediate control of massive haemorrhage from oesophagogastric varices. The usefulness of longterm sclerotherapy once short term sclerotherapy has been successfully carried out was assessed. Two treatment groups were studied: 50 patients were treated by 'combined' (short term followed by longterm) sclerotherapy; 56 patients were treated by short term sclerotherapy only. Patients included in the second group were treated by short term sclerotherapy only if a variceal rebleeding was present. The overall cumulative proportion of patients rebleeding was not significantly different in either group. Combined sclerotherapy patients, however, experienced less episodes of variceal haemorrhage and the source of haemorrhage was different (p < 0.002). Combined sclerotherapy was more efficient in preventing bleeding from oesophageal bleeding points but not those arising from a junctional source (p < 0.05). A greater incidence of oesophageal rebleeding was found in those patients whose first source of bleeding was oesophageal (p < 0.05). No significant difference was detected in survival expectancy between either group. In conclusion, after short term sclerotherapy is carried out successfully, those patients with bleeding from variceal bleeding points located on oesophageal mucosa should benefit most from a longterm sclerotherapy programme.

A physical map of two clusters containing the genes for six proinflammatory receptors.

The genes encoding for six receptors involved in the proinflammatory response lie on different chromosomes. Two receptors for N-formylpeptides (FPR1, FPR2), one homologue of these (FPRL2), and the receptor for complement fragment C5a (C5aR) are encoded by four genes mapped to human chromosome 19. The genes encoding two receptors for Interleukin-8 (IL8RA, IL8RB) have been located on human chromosome 2. In this report we describe the physical linkage between these genes in two different clusters. DNA fragments obtained by digestion with several restriction enzymes were separated by pulsed field gel electrophoresis. Nylon filters were hybridized with probes corresponding to the complete translated sequences of these genes. These probes were obtained from a human neutrophil cDNA-library. The four genes on chromosome 19 are contained in a 200 kilobase (kb) fragment. Both Interleukin-8 receptors are on a 150 kb fragment. The complete translated sequences for these genes were amplified from genomic DNA, indicating that they are contained in a single exon.

A physical map of the human complement component C6, C7, and C9 genes.

The genes for human complement components C6, C7, and C9 are linked on chromosome 5. In this report we describe the physical linkage between C6 and C7 genes. DNA fragments obtained by digestion with several rare-cutting restriction enzymes were separated through pulsed field gel electrophoresis. Hybridization with probes corresponding to the 5' and 3' ends of the three cDNAs showed common bands for the C6 and C7 genes. Both genes are contained in a NotI fragment of 500 kilobases (kb). Moreover, the presence of common 3' C6 and 3' C7 fragments indicates that both genes are oriented in a tail-to-tail, reverse way relative to transcription. No evidence of physical linkage between C9 and C6 or C7 was found in the range 50 kb-2.5 megabases (Mb).