The influence of sociodemographic factors and close relatives at hospital discharge and post hospital care of older people with complex care needs: nurses' perceptions on health inequity in three Nordic cities.

Hospital discharge of older people in need of both medical and social care following their hospital stay requires extensive coordination. This study aims to examine and compare the views of nurses in three Nordic cities on the influence of sociodemographic factors and having close relatives, for the hospital discharge and post hospital care of older people with complex health and social care needs. Thirty-five semi-structured interviews (Copenhagen n = 11, Tampere n = 8, Stockholm n = 16) with nurses were conducted. The nurses were identified through the researchers' networks, invitation and snowball sampling, and recruited from hospitals, primary care practices, home care units, home nursing units, and geriatric departments. The interviews were transcribed and analysed using thematic analysis. Interpretations were discussed and agreed within the team. Four main themes and 13 sub-themes were identified. Across the cities, informants reported that the patient's health status, rather than their gender or ethnicity, steered the discharge date and further care. Care costs, commonly reported in Tampere but also in Copenhagen and Stockholm including costs for medications and home help, were considered barriers for disadvantaged older people. Home situation, local arrangements and differences in collaboration between healthcare professionals at different sites also influenced the hospital discharge. Generally, the patient's health status steered the hospital discharge and post-hospital care. Close relatives were regarded important and a potential advantage. Some informants tried to compensate for the absence of close relatives, highlighting the importance of care systems that can compensate for this to minimise avoidable inequity. Supplementary Information: The online version contains supplementary material available at 10.1007/s10433-022-00701-6.

The impact of organisational characteristics of staff and facility on infectious disease outbreaks in care homes: a systematic review.

BACKGROUND: Infectious disease outbreaks are common in care homes, often with substantial impact on the rates of infection and mortality of the residents, who primarily are older people vulnerable to infections. There is growing evidence that organisational characteristics of staff and facility might play a role in infectious disease outbreaks however such evidence have not previously been systematically reviewed. Therefore, this systematic review aims to examine the impact of facility and staff characteristics on the risk of infectious disease outbreaks in care homes. METHODS: Five databases (MEDLINE, EMBASE, ProQuest, Web of Science, CINAHL) were searched. Studies considered for inclusion were of any design reporting on an outbreak of any infectious disease in one or more care homes providing care for primarily older people with original data on: facility size, facility location (urban/rural), facility design, use of temporary hired staff, staff compartmentalizing, residence of staff, and/or nursing aides hours per resident. Retrieved studies were screened, assessed for quality using CASP, and analysed employing a narrative synthesis. RESULTS: Sixteen studies (8 cohort studies, 6 cross-sectional studies, 2 case-control) were included from the search which generated 10,424 unique records. COVID-19 was the most commonly reported cause of outbreak (n = 11). The other studies focused on influenza, respiratory and gastrointestinal outbreaks. Most studies reported on the impact of facility size (n = 11) followed by facility design (n = 4), use of temporary hired staff (n = 3), facility location (n = 2), staff compartmentalizing (n = 2), nurse aides hours (n = 2) and residence of staff (n = 1). Findings suggest that urban location and larger facility size may be associated with greater risks of an infectious disease outbreak. Additionally, the risk of a larger outbreak seems lower in larger facilities. Whilst staff compartmentalizing may be associated with lower risk of an outbreak, staff residing in highly infected areas may be associated with greater risk of outbreak. The influence of facility design, use of temporary staff, and nurse aides hours remains unclear. CONCLUSIONS: This systematic review suggests that larger facilities have greater risks of infectious disease outbreaks, yet the risk of a larger outbreak seems lower in larger facilities. Due to lack of robust findings the impact of facility and staff characteristics on infectious disease outbreaks remain largely unknown. PROSPERO: CRD42020213585 .

The relationship between self-reported sensory impairments and psychosocial health in older adults: a 4-year follow-up study using the English Longitudinal Study of Ageing.

OBJECTIVES: To explore cross-sectional and longitudinal relationships between self-reported hearing and vision impairments and self-rated health, quality of life (QoL) and depressive symptoms at 4-year follow-up. STUDY DESIGN: The study involved cross-sectional and longitudinal analyses with 4-year follow-up using data from the English Longitudinal Study of Ageing. METHODS: Community-dwelling adults (n = 3931) aged ≥50 years from the English Longitudinal Study of Ageing participated in this study. Self-reported hearing and vision were defined as good or poor. Self-rated health was treated as a dichotomous variable (good and poor health). QoL was based on the 19-item Critical Appraisal Skills Programme and treated as a continuous variable (score 0-57). Depressive symptoms were assessed using the eight-item Center for Epidemiologic Studies Depression Scale (CES-D8) and defined as CES-D≥3. Relationships between sensory impairments and self-rated health and depressive symptoms were analysed using logistic regression. Linear regression was used to assess the relationships between sensory impairments and QoL. RESULTS: In cross-sectional analyses, both self-reported hearing and vision impairment were positively associated with all outcomes assessed. In longitudinal analyses, self-reported poor hearing and vision were associated with increased risks of poor self-rated health (hearing: odds ratio [OR] 1.65, 95% confidence interval [CI] 1.32, 2.05; vision: OR 1.57, 95% CI 1.16, 2.12) and depressive symptoms (hearing: OR 1.35, 95% CI 1.07, 1.71; vision: OR 1.44, 95% CI 1.09, 1.90) after adjustment for sociodemographic and lifestyle factors, chronic illness, mobility limitations and cognition. Poor hearing and poor vision were not associated with reduced QoL after adjustment for covariates. CONCLUSIONS: The findings stress the importance of identifying and addressing sensory impairments in older adults to improve their health and well-being.

Socio-demographic characteristics, lifestyle factors and burden of morbidity associated with self-reported hearing and vision impairments in older British community-dwelling men: a cross-sectional study.

BACKGROUND: Hearing and vision problems are common in older adults. We investigated the association of self-reported sensory impairment with lifestyle factors, chronic conditions, physical functioning, quality of life and social interaction. METHODS: A population-based cross-sectional study of participants of the British Regional Heart Study aged 63-85 years. RESULTS: A total of 3981 men (82% response rate) provided data. Twenty-seven per cent (n = 1074) reported hearing impairment including being able to hear with aid (n = 482), being unable to hear (no aid) (n = 424) and being unable to hear despite aid (n = 168). Three per cent (n = 124) reported vision impairment. Not being able to hear, irrespective of use of hearing aid, was associated with poor quality of life, poor social interaction and poor physical functioning. Men who could not hear despite hearing aid were more likely to report coronary heart disease (CHD) [age-adjusted odds ratios (ORs) 1.89 (95% confidence interval 1.36-2.63)]. Vision impairment was associated with symptoms of CHD including breathlessness [OR 2.06 (1.38-3.06)] and chest pain [OR 1.58 (1.07-2.35)]. Vision impairment was also associated with poor quality of life, poor social interaction and poor physical functioning. CONCLUSIONS: Sensory impairment is associated with poor physical functioning, poor health and poor social interaction in older men. Further research is warranted on pathways underlying these associations.

Crystal structure of a superantigen bound to MHC class II displays zinc and peptide dependence.

The three-dimensional structure of a bacterial superantigen, Staphylococcus aureus enterotoxin H (SEH), bound to human major histocompatibility complex (MHC) class II (HLA-DR1) has been determined by X-ray crystallography to 2.6 A resolution (1HXY). The superantigen binds on top of HLA-DR1 in a completely different way from earlier co-crystallized superantigens from S.aureus. SEH interacts with high affinity through a zinc ion with the beta1 chain of HLA-DR1 and also with the peptide presented by HLA-DR1. The structure suggests that all superantigens interacting with MHC class II in a zinc-dependent manner present the superantigen in a common way. This suggests a new model for ternary complex formation with the T-cell receptor (TCR), in which a contact between the TCR and the MHC class II is unlikely.

Crystals of a mutant form of ribosomal protein L22 rendering bacterial ribosomes resistant to erythromycin.

A mutant form of Thermus thermophilus ribosomal protein L22 responsible for erythromycin resistance has been overexpressed in Escherichia coli, purified to homogeneity and crystallized using the hanging-drop vapour-diffusion technique. While several different crystallization conditions were found, only one set of conditions yielded crystals suitable for X-ray diffraction analysis. These crystals grow as thick plates, with unit-cell parameters a = 31.8, b = 86.59, c = 38.96 A, beta = 104.47 degrees. The crystals belong to the space group P2(1) and diffract to 1.8 A resolution. On the basis of density calculations, two monomers are predicted per asymmetric unit (V(M) = 2.06 A(3) Da(-1)), with a solvent content of 40%.

Structure of ribosomal protein TL5 complexed with RNA provides new insights into the CTC family of stress proteins.

The crystal structure of Thermus thermophilus ribosomal protein TL5 in complex with a fragment of Escherichia coli 5S rRNA has been determined at 2.3 A resolution. The protein consists of two domains. The structure of the N-terminal domain is close to the structure of E. coli ribosomal protein L25, but the C-terminal domain represents a new fold composed of seven beta-strands connected by long loops. TL5 binds to the RNA through its N-terminal domain, whereas the C-terminal domain is not included in this interaction. Cd(2+) ions, the presence of which improved the crystal quality significantly, bind only to the protein component of the complex and stabilize the protein molecule itself and the interactions between the two molecules in the asymmetric unit of the crystal. The TL5 sequence reveals homology to the so-called general stress protein CTC. The hydrophobic cores which stabilize both TL5 domains are highly conserved in CTC proteins. Thus, all CTC proteins may fold with a topology close to that of TL5.

Mutations in the G-domain of elongation factor G from Thermus thermophilus affect both its interaction with GTP and fusidic acid.

Two hypersensitive and two resistant variants of elongation factor-G (EF-G) toward fusidic acid are studied in comparison with the wild type factor. All mutated proteins are active in a cell-free translation system and ribosome-dependent GTP hydrolysis. The EF-G variants with the Thr-84-->Ala or Asp-109-->Lys mutations bring about a strong resistance of EF-G to the antibiotic, whereas the EF-Gs with substitutions Gly-16-->Val or Glu-119-->Lys are the first examples of fusidic acid-hypersensitive factors. A correlation between fusidic acid resistance of EF-G mutants and their affinity to GTP are revealed in this study, although their interactions with GDP are not changed. Thus, fusidic acid-hypersensitive mutants have the high affinity to an uncleavable GTP analog, but the association of resistant mutants with GTP is decreased. The effects of either fusidic acid-sensitive or resistant mutations can be explained by the conformational changes in the EF-G molecule, which influence its GTP-binding center. The results presented in this paper indicate that fusidic acid-sensitive mutant factors have a conformation favorable for GTP binding and subsequent interaction with the ribosomes.

The end of the beginning: structural studies of ribosomal proteins.

Work on the structural biology of ribosomes has progressed rapidly over the past few years. It has come to a stage at which the structures of the individual components are no longer of interest, except for those that still present ambiguous information about their structure because of conformational dynamics, as well as for those that show very little homology with their counterparts from other species or other kingdoms. The recently solved structure of protein L7/L12 and its proposed modes of dimerization have helped to understand the structural flexibility of this protein, which occurs as two dimers in the ribosome. The structure provides a missing link for many previous biochemical and functional studies.

Structure of a mutant EF-G reveals domain III and possibly the fusidic acid binding site.

The crystal structure of Thermus thermophilus elongation factor G (EF-G) carrying the point mutation His573Ala was determined at a resolution of 2.8 A. The mutant has a more closed structure than that previously reported for wild-type EF-G. This is obtained by a 10 degrees rigid rotation of domains III, IV and V with regard to domains I and II. This rotation results in a displacement of the tip of domain IV by approximately 9 A. The structure of domain III is now fully visible and reveals the double split beta-alpha-beta motif also observed for EF-G domain V and for several ribosomal proteins. A large number of fusidic acid resistant mutations found in domain III have now been possible to locate. Possible locations for the effector loop and a possible binding site for fusidic acid are discussed in relation to some of the fusidic acid resistant mutations.

A decade of progress in understanding the structural basis of protein synthesis.

The key reaction of protein synthesis, peptidyl transfer, is catalysed in all living organisms by the ribosome - an advanced and highly efficient molecular machine. During the last decade extensive X-ray crystallographic and NMR studies of the three-dimensional structure of ribosomal proteins, ribosomal RNA components and their complexes with ribosomal proteins, and of several translation factors in different functional states have taken us to a new level of understanding of the mechanism of function of the protein synthesis machinery. Among the new remarkable features revealed by structural studies, is the mimicry of the tRNA molecule by elongation factor G, ribosomal recycling factor and the eukaryotic release factor 1. Several other translation factors, for which three-dimensional structures are not yet known, are also expected to show some form of tRNA mimicry. The efforts of several crystallographic and biochemical groups have resulted in the determination by X-ray crystallography of the structures of the 30S and 50S subunits at moderate resolution, and of the structure of the 70S subunit both by X-ray crystallography and cryo-electron microscopy (EM). In addition, low resolution cryo-EM models of the ribosome with different translation factors and tRNA have been obtained. The new ribosomal models allowed for the first time a clear identification of the functional centres of the ribosome and of the binding sites for tRNA and ribosomal proteins with known three-dimensional structure. The new structural data have opened a way for the design of new experiments aimed at deeper understanding at an atomic level of the dynamics of the system.

Archaeal ribosomal protein L1: the structure provides new insights into RNA binding of the L1 protein family.

BACKGROUND: L1 is an important primary rRNA-binding protein, as well as a translational repressor that binds mRNA. It was shown that L1 proteins from some bacteria and archaea are functionally interchangeable within the ribosome and in the repression of translation. The crystal structure of bacterial L1 from Thermus thermophilus (TthL1) has previously been determined. RESULTS: We report here the first structure of a ribosomal protein from archaea, L1 from Methanococcus jannaschii (MjaL1). The overall shape of the two-domain molecule differs dramatically from that of its bacterial counterpart (TthL1) because of the different relative orientations of the domains. Two strictly conserved regions of the amino acid sequence, each belonging to one of the domains and positioned close to each other in the interdomain cavity of TthL1, are separated by about 25 A in MjaL1 owing to a significant opening of the structure. These regions are structurally highly conserved and are proposed to be the specific RNA-binding sites. CONCLUSIONS: The unusually high RNA-binding affinity of MjaL1 might be explained by the exposure of its highly conserved regions. The open conformation of MjaL1 is strongly stabilized by nonconserved interdomain interactions and suggests that the closed conformations of L1 (as in TthL1) open upon RNA binding. Comparison of the two L1 protein structures reveals a high conformational variability of this ribosomal protein. Determination of the MjaL1 structure offers an additional variant for fitting the L1 protein into electron-density maps of the 50S ribosomal subunit.

Extremely thermostable elongation factor G from Aquifex aeolicus: cloning, expression, purification, and characterization in a heterologous translation system.

The fus gene of the translation factor G (EF-G) from the hyperthermophilic bacterium Aquifex aeolicus was cloned under control of a phage promoter and overexpressed in Escherichia coli with the T7 RNA polymerase system. A heat denaturation step at 95 degrees C was used to purify the protein from the cell extract. This approach simplified the chromatographic procedures and decreased the protein loss since most of Escherichia coli proteins were denatured and precipitated. Ten milligrams of the highly purified protein was isolated from 4 liters of induced culture. The overproduced EF-G was active in ribosome-dependent GTP hydrolysis and a poly(U)-directed polyphenylalanine translation system with E. coli 70S ribosomes. The method presented here might facilitate functional and structural studies of important components of the protein biosynthesis system.

The crystallography beamline I711 at MAX II.

A new X-ray crystallographic beamline is operational at the MAX II synchrotron in Lund. The beamline has been in regular use since August 1998 and is used both for macro- and small molecule diffraction as well as powder diffraction experiments. The radiation source is a 1.8 T multipole wiggler. The beam is focused vertically by a bendable mirror and horizontally by an asymmetrically cut Si(111) monochromator. The wavelength range is 0.8-1.55 A with a measured flux at 1 A of more than 10(11) photons s(-1) in 0.3 mm x 0.3 mm at the sample position. The station is currently equipped with a Mar345 imaging plate, a Bruker Smart 1000 area CCD detector and a Huber imaging-plate Guinier camera. An ADSC 210 area CCD detector is planned to be installed during 2000.

Crystal structure of Thermotoga maritima ribosome recycling factor: a tRNA mimic.

Ribosome recycling factor (RRF), together with elongation factor G (EF-G), catalyzes recycling of ribosomes after one round of protein synthesis. The crystal structure of RRF was determined at 2.55 angstrom resolution. The protein has an unusual fold where domain I is a long three-helix bundle and domain II is a three-layer beta/alpha/beta sandwich. The molecule superimposes almost perfectly with a transfer RNA (tRNA) except that the amino acid-binding 3' end is missing. The mimicry suggests that RRF interacts with the posttermination ribosomal complex in a similar manner to a tRNA, leading to disassembly of the complex. The structural arrangement of this mimicry is entirely different from that of other cases of less pronounced mimicry of tRNA so far described.

N-terminal domain, residues 1-91, of ribosomal protein TL5 from Thermus thermophilus binds specifically and strongly to the region of 5S rRNA containing loop E.

In this work we show for the first time that the overproduced N-terminal fragment (residues 1-91) of ribosomal protein TL5 binds specifically to 5S rRNA and that the region of this fragment containing residues 80-91 is a necessity for its RNA-binding activity. The fragment of Escherichia coli 5S rRNA protected by TL5 against RNase A hydrolysis was isolated and sequenced. This 39 nucleotides fragment contains loop E and helices IV and V of 5S rRNA. The isolated RNA fragment forms stable complexes with TL5 and its N-terminal domain. Crystals of TL5 in complex with the RNA fragment diffracting to 2.75 A resolution were obtained.

Crystallization and preliminary X-ray analysis of Thermotoga maritima ribosome recycling factor.

Thermotoga maritima ribosome recycling factor (RRF) is one of the proteins catalyzing the fourth step in prokaryotic protein synthesis, ribosome recycling. The RRF protein was crystallized with ammonium sulfate. Native diffraction data to 2.55 A resolution were obtained at the MAX II synchrotron from a flash-frozen crystal at 100 K. The crystals belong to space group P4(1)2(1)2 or P4(3)2(1)2, with unit-cell parameters a = b = 47, c = 298 A, and probably contain one monomer per asymmetric unit.