Pleuropulmonary blastoma (PPB) and other DICER1-associated high-grade malignancies are morphologically, genetically and epigenetically related - A comparative study of 4 PPBs and 6 sarcomas.

DICER1-related tumors occur hereditary or sporadically, with high-grade malignancies sharing clinicopathological and (epi)genetic features. We compared 4 pleuropulmonary blastomas (PPBs) and 6 sarcomas by mutation analysis, whole transcriptome sequencing and methylation profiling. 9/10 patients were female. PPB patients were 0-4 years. 3/4 were alive; 2 without disease. One patient died of metastatic disease (median follow-up, 16 months). Sarcoma patients were 16-56 years. Locations included: uterine cervix/corpus (3/1), soft tissue back/shoulder (1) and paravertebral (1). 5/6 patients were alive; 2 developed metastases: intracranial (1) and lung and kidney (1) (median follow-up, 17 months). The deceased patient previously had a PPB and a Sertoli-Leydig cell tumor. Histologically, tumors showed atypical primitive-looking cells with incomplete rhabdomyoblastic differentiation and cartilage (n = 5). Immunohistochemistry demonstrated desmin- (n = 9/10), myogenin- (n = 6/10) and keratin positivity (n = 1/1). Eight cases harbored biallelic DICER1 mutations with confirmed germline mutations in 4 cases. Two cases showed a monoallelic mutation. By RNA expression- and methylation profiling, distinct clustering of our cases was seen demonstrating a close relationship on (epi)genetic level and similarities to embryonal rhabdomyosarcoma. In conclusion, this study shows overlapping morphological, immunohistochemical and (epi)genetic features of PPBs and DICER1-associated high-grade sarcomas, arguing that these neoplasms form a spectrum with a broad clinicopathological range.

A three perspective study of the sense of home of nursing home residents: the views of residents, care professionals and relatives.

BACKGROUND: The sense of home of nursing home residents is a multifactorial phenomenon which is important for the quality of living. This purpose of this study is to investigate the factors influencing the sense of home of older adults residing in the nursing home from the perspective of residents, relatives and care professionals. METHODS: A total of 78 participants (n = 24 residents, n = 18 relatives and n = 26 care professionals) from 4 nursing homes in the Netherlands engaged in a qualitative study, in which photography was as a supportive tool for subsequent interviews and focus groups. The data were analyzed based on open ended coding, axial coding and selective coding. RESULTS: The sense of home of nursing home residents is influenced by a number of jointly identified factors, including the building and interior design; eating and drinking; autonomy and control; involvement of relatives; engagement with others and activities; quality of care are shared themes. Residents and relatives stressed the importance of having a connection with nature and the outdoors, as well as coping strategies. Relatives and care professionals emphasized the role the organization of facilitation of care played, as well as making residents feel like they still matter. CONCLUSIONS: The sense of home of nursing home residents is influenced by a multitude of factors related to the psychology of the residents, and the social and built environmental contexts. A holistic understanding of which factors influence the sense of home of residents can lead to strategies to optimize this sense of home. This study also indicated that the nursing home has a dual nature as a place of residence and a place where people are supported through numerous care strategies.

The Factors Influencing the Sense of Home in Nursing Homes: A Systematic Review from the Perspective of Residents.

Purpose. To provide an overview of factors influencing the sense of home of older adults residing in the nursing home. Methods. A systematic review was conducted. Inclusion criteria were (1) original and peer-reviewed research, (2) qualitative, quantitative, or mixed methods research, (3) research about nursing home residents (or similar type of housing), and (4) research on the sense of home, meaning of home, at-homeness, or homelikeness. Results. Seventeen mainly qualitative articles were included. The sense of home of nursing home residents is influenced by 15 factors, divided into three themes: (1) psychological factors (sense of acknowledgement, preservation of one's habits and values, autonomy and control, and coping); (2) social factors (interaction and relationship with staff, residents, family and friends, and pets) and activities; and (3) the built environment (private space and (quasi-)public space, personal belongings, technology, look and feel, and the outdoors and location). Conclusions. The sense of home is influenced by numerous factors related to the psychology of the residents and the social and built environmental contexts. Further research is needed to determine if and how the identified factors are interrelated, if perspectives of various stakeholders involved differ, and how the factors can be improved in practice.

FOXP1 acts through a negative feedback loop to suppress FOXO-induced apoptosis.

Transcriptional activity of Forkhead box transcription factor class O (FOXO) proteins can result in a variety of cellular outcomes depending on cell type and activating stimulus. These transcription factors are negatively regulated by the phosphoinositol 3-kinase (PI3K)-protein kinase B (PKB) signaling pathway, which is thought to have a pivotal role in regulating survival of tumor cells in a variety of cancers. Recently, it has become clear that FOXO proteins can promote resistance to anti-cancer therapeutics, designed to inhibit PI3K-PKB activity, by inducing the expression of proteins that provide feedback at different levels of this pathway. We questioned whether such a feedback mechanism may also exist directly at the level of FOXO-induced transcription. To identify critical modulators of FOXO transcriptional output, we performed gene expression analyses after conditional activation of key components of the PI3K-PKB-FOXO signaling pathway and identified FOXP1 as a direct FOXO transcriptional target. Using chromatin immunoprecipitation followed by next-generation sequencing, we show that FOXP1 binds enhancers that are pre-occupied by FOXO3. By sequencing the transcriptomes of cells in which FOXO is specifically activated in the absence of FOXP1, we demonstrate that FOXP1 can modulate the expression of a specific subset of FOXO target genes, including inhibiting expression of the pro-apoptotic gene BIK. FOXO activation in FOXP1-knockdown cells resulted in increased cell death, demonstrating that FOXP1 prevents FOXO-induced apoptosis. We therefore propose that FOXP1 represents an important modulator of FOXO-induced transcription, promoting cellular survival.

Refined solution structure of the dimeric N-terminal HHCC domain of HIV-2 integrase.

The solution structure of the dimeric N-terminal domain of HIV-2 integrase (residues 1-55, named IN(1-55)) has been determined using NMR spectroscopy. The structure of the monomer, which was already reported previously [Eijkelenboom et al. (1997) Curr. Biol., 7, 739-746], consists of four alpha-helices and is well defined. Helices alpha1, alpha2 and alpha3 form a three-helix bundle that is stabilized by zinc binding to His12, His16, Cys40 and Cys43. The dimer interface is formed by the N-terminal tail and the first half of helix alpha3. The orientation of the two monomeric units with respect to each other shows considerable variation. 15N relaxation studies have been used to characterize the nature of the intermonomeric disorder. Comparison of the dimer interface with that of the well-defined dimer interface of HIV-1 IN(1-55) shows that the latter is stabilized by additional hydrophobic interactions and a potential salt bridge. Similar interactions cannot be formed in HIV-2 IN(1-55) [Cai et al. (1997) Nat. Struct. Biol., 4, 567-577], where the corresponding residues are positively charged and neutral ones.

Refined solution structure of the C-terminal DNA-binding domain of human immunovirus-1 integrase.

The structure of the C-terminal DNA-binding domain of human immunovirus-1 integrase has been refined using nuclear magnetic resonance spectroscopy. The protein is a dimer in solution and shows a well-defined dimer interface. The folding topology of the monomer consists of a five-stranded beta-barrel that resembles that of Src homology 3 domains. Compared with our previously reported structure, the structure is now defined far better. The final 42 structures display a back-bone root mean square deviation versus the average of 0.46 A. Correlation of the structure with recent mutagenesis studies suggests two possible models for DNA binding. Proteins 1999;36:556-564.

The solution structure of the amino-terminal HHCC domain of HIV-2 integrase: a three-helix bundle stabilized by zinc.

BACKGROUND: Integrase mediates a crucial step in the life cycle of the human immunodeficiency virus (HIV). The enzyme cleaves the viral DNA ends in a sequence-dependent manner and couples the newly generated hydroxyl groups to phosphates in the target DNA. Three domains have been identified in HIV integrase: an amino-terminal domain, a central catalytic core and a carboxy-terminal DNA-binding domain. The amino-terminal region is the only domain with unknown structure thus far. This domain, which is known to bind zinc, contains a HHCC motif that is conserved in retroviral integrases. Although the exact function of this domain is unknown, it is required for cleavage and integration. RESULTS: The three-dimensional structure of the amino-terminal domain of HIV-2 integrase has been determined using two-dimensional and three-dimensional nuclear magnetic resonance data. We obtained 20 final structures, calculated using 693 nuclear Overhauser effects, which display a backbone root-mean square deviation versus the average of 0.25 A for the well defined region. The structure consists of three alpha helices and a helical turn. The zinc is coordinated with His 12 via the N epsilon 2 atom, with His16 via the N delta 1 atom and with the sulfur atoms of Cys40 and Cys43. The alpha helices form a three-helix bundle that is stabilized by this zinc-binding unit. The helical arrangement is similar to that found in the DNA-binding domains of the trp repressor, the prd paired domain and Tc3A transposase. CONCLUSION: The amino-terminal domain of HIV-2 integrase has a remarkable hybrid structure combining features of a three-helix bundle fold with a zinc-binding HHCC motif. This structure shows no similarity with any of the known zinc-finger structures. The strictly conserved residues of the HHCC motif of retroviral integrases are involved in metal coordination, whereas many other well conserved hydrophobic residues are part of the protein core.

The DNA-binding domain of HIV-1 integrase has an SH3-like fold.

We have determined the solution structure of the DNA-binding domain of HIV-1 integrase by nuclear magnetic resonance spectroscopy. In solution, this carboxyterminal region of integrase forms a homodimer, consisting of two structures that closely resemble Src-homology 3 (SH3) domains. Lys 264, previously identified by mutagenesis studies to be important for DNA binding of the integrase, as well as several adjacent basic amino acids are solvent exposed. The identification of an SH3-like domain in integrase provides a new potential target for drug design.

14N population transfers in two-dimensional 13C-14N-1H triple-resonance magic-angle spinning nuclear magnetic resonance spectroscopy.

A two-dimensional (2D) experiment has been used to show that 14N irradiation and magic-angle spinning (MAS) results in population transfers between the 14N Zeeman levels. This experiment was applied to a sample of N-acetyl-D,L-valine, a material where asymmetric doublets resulting from 13C-14N dipolar coupling are clearly resolved in the 13C spectrum at a field of 7 T for Carbon atoms directly bonded to the nitrogen atom. The 13C transverse magnetization was allowed to evolve in the F1 and F2 dimensions, and the 14N spins were irradiated during the mixing period. Cross-peaks were observed in the 2D 13C spectrum between the two peaks of the CH asymmetric doublet. Since one peak of the doublet results primarily from coupling to the [formula: see text] state and the other peak from coupling to [formula: see text] states, population changes between the 14N Zeeman levels have occurred during the mixing period. These population transfers are a consequence of the time dependence of the 14N quadrupole splitting Q under MAS conditions and 14N irradiation. Level anti-crossings of the 14N Zeeman levels occur at the zero-crossings of Q, and a continuous and slow change in Q will result in the transfer of 14N populations between the different Zeeman levels. If these passages are adiabatic, then the system returns to its original state after two zero-crossings. This is consistent with the experimental observation that the intensities of the cross-peaks for 14N irradiation are greater for half a rotor period than a full rotor period.