Implementation of Ireland's first state-funded day-case total hip arthroplasty programme.

BACKGROUND: Over the last two decades, many elective procedures have transitioned to day-case surgery thanks to the introduction of 'enhanced recovery' protocols. Only recently has total hip arthroplasty been considered a candidate for day-case surgery, as it was once associated with significant pain, mobility impairment and prolonged postoperative recovery. The National Orthopaedic Hospital Cappagh became the first public hospital in Ireland to set up a day-case total hip arthroplasty service in June 2018, and since then has performed over 109 such cases. AIMS: We outline our day-case total hip arthroplasty pathway, with specific focus on anaesthetic considerations. We report rates of failed discharge and readmission. RESULTS: We achieved successful same-day discharge in 90.8% of our first 109 cases. Readmission rate was 4.6%. CONCLUSION: Our experience of implementing a day-case total hip arthroplasty pathway was highly positive and congruent with expectations from the literature. With appropriate patient selection and education, day-case total hip arthroplasty is not just safe, but of benefit to both patients and healthcare systems.

Centriole splitting caused by loss of the centrosomal linker protein C-NAP1 reduces centriolar satellite density and impedes centrosome amplification.

Duplication of the centrosomes is a tightly regulated process. Abnormal centrosome numbers can impair cell division and cause changes in how cells migrate. Duplicated centrosomes are held together by a proteinaceous linker made up of rootletin filaments anchored to the centrioles by C-NAP1. This linker is removed in a NEK2A kinase-dependent manner as mitosis begins. To explore C-NAP1 activities in regulating centrosome activities, we used genome editing to ablate it. C-NAP1-null cells were viable and had an increased frequency of premature centriole separation, accompanied by reduced density of the centriolar satellites, with reexpression of C-NAP1 rescuing both phenotypes. We found that the primary cilium, a signaling structure that arises from the mother centriole docked to the cell membrane, was intact in the absence of C-NAP1, although components of the ciliary rootlet were aberrantly localized away from the base of the cilium. C-NAP1-deficient cells were capable of signaling through the cilium, as determined by gene expression analysis after fluid flow-induced shear stress and the relocalization of components of the Hedgehog pathway. Centrosome amplification induced by DNA damage or by PLK4 or CDK2 overexpression was markedly reduced in the absence of C-NAP1. We conclude that centriole splitting reduces the local density of key centriolar precursors to impede overduplication.

SUMO ligase activity of vertebrate Mms21/Nse2 is required for efficient DNA repair but not for Smc5/6 complex stability.

Nse2/Mms21 is an E3 SUMO ligase component of the Smc5/6 complex, which plays multiple roles in maintaining genome stability. To study the functions of the vertebrate Nse2 orthologue, we generated Nse2-deficient chicken DT40 cells. Nse2 was dispensable for DT40 cell viability and required for efficient repair of bulky DNA lesions, although Nse2-deficient cells showed normal sensitivity to ionising radiation-induced DNA damage. Homologous recombination activities were reduced in Nse2(-/-/-) cells. Nse2 deficiency destabilised Smc5, but not Smc6. In rescue experiments, we found that the SUMO ligase activity of Nse2 was required for an efficient response to MMS- or cis-platin-induced DNA damage, and for homologous recombination, but not for Smc5 stability. Gel filtration analysis indicated that Smc5 and Nse2 remain associated during the cell cycle and after DNA damage and Smc5/Smc6 association is independent of Nse2. Analysis of Nse2(-/-/-)Smc5(-) clones, which were viable although slow-growing, showed no significant increase in DNA damage sensitivity. We propose that Nse2 determines the activity, but not the assembly, of the Smc5/6 complex in vertebrate cells, and this activity requires the Nse2 SUMO ligase function.

High-fat diets promote insulin resistance through cytokine gene expression in growing female rats.

To determine if tumor necrosis factor alpha (TNF-alpha) and interleukin-6 (IL-6). IL-6 gene expression is influenced by amount and source of dietary fat, 30 weanling female rats were randomly assigned to a moderate-fat soybean oil (MFS; 22% of total energy fed as fat), high-fat (HF) soybean oil (HFS; 39% of total energy fed as fat), or HF tallow (HFT; 39% of total energy fed as fat) diet treatments. Oral glucose tolerance tests (OGTT) were conducted serially over 10 weeks of treatment. HFT and HFS rats gained more weight and had greater body fat than the MFS rats fed similar amounts of energy. Both groups of HF-fed rats had greater (P<.05) insulin resistance (homeostasis model assessment) than MFS-fed rats. TNF-alpha mRNA abundance quantified by real-time reverse transcriptase-polymerase chain reaction was greater (P<.05) in liver and lower (P<.05) in adipose tissue in HFT compared to HFS and MFS rats. There were positive correlations (P<.05) between hepatic TNF-alpha mRNA and insulin resistance, and negative correlations between insulin sensitivity and hepatic TNF-alpha mRNA and hepatic IL-6 mRNA. During Week 3 and Week 6 OGTTs, hyperinsulinemic responses were observed in the HFT group, after which, on Week 9, insulin secretion was diminished in response to the OGTT, suggesting impaired pancreatic insulin secretion. HFS rats exhibited insulin resistance on Week 9 OGTT. In summary, an HFT diet fed to growing female rats caused insulin resistance associated with increased hepatic TNF-alpha mRNA leading to pancreatic insufficiency. Early-onset insulin resistance related to the inflammatory process in obesity is influenced by the amount and type of fat in the diet.

Characterization of freezing tolerance and vernalization in Vern-, a spring-type Brassica napus line derived from a winter cross.

Exposure of winter brassicas to periods of low temperature decreases the transition required from vegetative to reproductive growth. This low-temperature exposure also results in the acquisition of freezing tolerance. To investigate the relationship between vernalization and freezing tolerance, homozygous microspore-derived (DH) lines were developed from reciprocal crosses between two winter cultivars of Brassica napus L., cv. Cascade and cv. Rebel. A resulting line, termed Vern-, expressed a high degree of freezing tolerance and was selected for study. Analysis of growth and development revealed that Vern- is a true spring type, having completely lost the vernalization requirement. Using markers previously mapped in B. rapa, it was concluded that Vern- inherited freezing-tolerance alleles from Cascade. With regard to vernalization and flowering time, Rebel, although traditionally classified as a winter type, carries spring alleles at the major and some of the minor loci. Vern- inherited these alleles from Rebel, in addition to one spring allele from Cascade. Thus, spring alleles from both parents were critical in establishing the spring phenotype observed in Vern-.

Regulation and characterization of four CBF transcription factors from Brassica napus.

Four orthologues of the Arabidopsis CBF/Dreb transcriptional activator genes were isolated from the winter Brassica napus, cv. Jet neuf. All four BNCBF clones encode a putative DRE/CRT (LTRE)-binding protein with an AP2 DNA-binding domain, a putative nuclear localization signal and a possible acidic activation domain. Deduced amino acid sequences suggested that BNCBFs 5, 7and 16 are very similar to the Arabidopsis CBFI whereas BNCBF17 is different in that it contains two extra regions of 16 and 21 amino acids in the acidic domain. Transcripts hybridizing specifically to BNCBF17 and to one or more of the other BNCBFs accumulated in leaves within 30 min of cold exposure of the Brassica seedlings and preceded transcript accumulation of the cold-inducible BN28 gene, a Brassica orthologue of the cor6.6 or KIN gene from Arabidopsis. Cold-induced accumulation of BNCBF17 mRNA was rapid but was short-lived compared to transcripts hybridizing to BNCBF5/7/16. Transcripts hybridizing to one or more of BNCBF5/7/16 accumulated at low levels after the plants were subjected to prolonged exposure to salt stress. BNCBF17 was not responsive to salt stress. BNCBF transcript accumulation was similar in both spring and winter Brassica but the persistence of the transcripts in the cold were generally shorter in the spring than in the winter type. BNCBF5 and 17 proteins bind in vitro to the LTRE domains of the cold-inducible BN115 (cor15a orthologue) or BN28 promoters. Differential binding preferences, however, to LTREs between BNI 15 and BN28 were observed. Mutation of the core CCGAC sequence of the LTRE indicated that BNCBF17 had a lower sequence binding specificity than BNCBF5. Furthermore, experiments indicated that the LTREs were able to drive BNCBF5 and 17 trans-activation of the Lac-Z reporter gene in yeast. We conclude that the BNCBFs reported here could function as trans-acting factors in low-temperature responses in Brassica, controlling the expression of cold-induced genes through an ABA-independent pathway.