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1.
Infect Prev Pract ; 4(1): 100188, 2022 Mar.
Article in English | MEDLINE | ID: mdl-35036902

ABSTRACT

Healthcare associated infections (HCAI) are a prevalent preventable cause of morbidity and mortality. Improving hand hygiene adherence is important for HCAI prevention. In this feasibility study, the objective was to determine if a humanoid robot could act as a novel single reminder intervention to improve hand hygiene adherence in a hospital setting. DAVE, a social humanoid robot, improved hand hygiene adherence at the entrance to a tertiary hospital and outpatient department, which was low at baseline, by 29%. DAVE shows promise as a novel intervention to improve hand hygiene adherence.

2.
Int J Food Sci Nutr ; 72(6): 816-832, 2021 Sep.
Article in English | MEDLINE | ID: mdl-33455470

ABSTRACT

Personalised nutrition (PN) products and services have the potential to enhance the health and quality of life of older adults. However, PN innovation is challenging and requires specific competencies and supportive collaborations. This paper reports findings from a Collective Intelligence Scenario-Based Design session conducted with PN experts as part of the Horizon 2020 project INCluSilver, which aims to support the development of products, services, and systems that improve the health and quality of life of older adults through innovation in PN. Experts identified challenges to the design of PN products and services and barriers that small and medium enterprises (SMEs) face when innovating PN products and services for older adults. Options to address these barriers were generated and specific SME competencies supporting PN innovation were identified. This study provides a useful framework for understanding the challenges, opportunities, and key competencies needed to innovate PN products and services for older adults.


Subject(s)
Diet , Nutritional Status , Quality of Life , Aged , Dietetics , Humans
3.
Syst Rev ; 8(1): 324, 2019 12 13.
Article in English | MEDLINE | ID: mdl-31836007

ABSTRACT

BACKGROUND: Fatigue is a common symptom in cancer patients that can persist beyond the curative treatment phase. This systematic review evaluated the effectiveness of psychological interventions for cancer-related fatigue in post-treatment cancer survivors. METHODS: We searched relevant online databases and sources of grey literature. Randomised controlled trials (RCTs) evaluating psychological interventions in adult cancer patients after the completion of treatment, with fatigue as an outcome measure, were included. Two review authors extracted data independently from the selected studies and assessed the methodological quality using the Cochrane Collaboration Risk of Bias Tool. RESULTS: Thirty-three psychological interventions were identified. The sample size of the included studies varied between 28 and 409, with 4525 participants overall. Twenty-three of the included studies reported a significant effect of the interventions on reducing fatigue in cancer survivors. Most interventions focused on psychoeducation, mindfulness, cognitive or behaviour therapy-oriented strategies. However, studies differed widely in terms of measurement tools used to assess fatigue, mode, duration and frequency of the intervention delivery. CONCLUSIONS: This review showed some tentative support for psychological interventions for fatigue after cancer treatment. However, as the RCTs were heterogeneous in nature and the number of high-quality studies was limited, definitive conclusions are not yet possible. With the growing need for stage-specific research in cancer, this review sought to inform current practice and to summarise the existing evidence base of randomised controlled trials in the area. SYSTEMATIC REVIEW REGISTRATION: PROSPERO registration number: CRD42014015219.


Subject(s)
Cancer Survivors/psychology , Cognitive Behavioral Therapy , Fatigue/therapy , Mindfulness , Randomized Controlled Trials as Topic , Humans , Quality of Life
4.
Aliment Pharmacol Ther ; 47(7): 940-950, 2018 Apr.
Article in English | MEDLINE | ID: mdl-29460418

ABSTRACT

BACKGROUND: The validity of the eosinophilic oesophagitis (EoE) histologic scoring system (EoEHSS) has been demonstrated, but only preliminary reliability data exist. AIM: Formally assess the reliability of the EoEHSS and additional histologic features. METHODS: Four expert gastrointestinal pathologists independently reviewed slides from adult patients with EoE (N = 45) twice, in random order, using standardised training materials and scoring conventions for the EoEHSS and additional histologic features agreed upon during a modified Delphi process. Intra- and inter-rater reliability for scoring the EoEHSS, a visual analogue scale (VAS) of overall histopathologic disease severity, and additional histologic features were assessed using intra-class correlation coefficients (ICCs). RESULTS: Almost perfect intra-rater reliability was observed for the composite EoEHSS scores and the VAS. Inter-rater reliability was also almost perfect for the composite EoEHSS scores and substantial for the VAS. Of the EoEHSS items, eosinophilic inflammation was associated with the highest ICC estimates and consistent with almost perfect intra- and inter-rater reliability. With the exception of dyskeratotic epithelial cells and surface epithelial alteration, ICC estimates for the remaining EoEHSS items were above the benchmarks for substantial intra-rater, and moderate inter-rater reliability. Estimation of peak eosinophil count and number of lamina propria eosinophils were associated with the highest ICC estimates among the exploratory items. CONCLUSION: The composite EoEHSS and most component items are associated with substantial reliability when assessed by central pathologists. Future studies should assess responsiveness of the score to change after a therapeutic intervention to facilitate its use in clinical trials.


Subject(s)
Eosinophilic Esophagitis/diagnosis , Histological Techniques , Adult , Eosinophilic Esophagitis/pathology , Eosinophils/pathology , Female , Histological Techniques/standards , Humans , Leukocyte Count , Male , Middle Aged , Observer Variation , Predictive Value of Tests , Reproducibility of Results , Retrospective Studies , Visual Analog Scale
5.
Ir Med J ; 110(7): 617, 2017 Aug 12.
Article in English | MEDLINE | ID: mdl-29168999

ABSTRACT

Gestational Diabetes Mellitus (GDM) is a growing concern and poses serious health risks to both mother and child1. The current study explores the psychological determinants of exercise behaviour in a sample of pregnant women with GDM. A cross-sectional survey design was employed to examine exercise behaviour, illness perceptions, perceived barriers and benefits, exercise beliefs, and exercise self-efficacy using validated questionnaires. A sample of 46 pregnant women was recruited from University College Hospital Galway, Letterkenny General Hospital, Cork University Hospital and Mayo General Hospital in Castlebar. Participant's varied; age (22-44 years), body mass index (19-41). High mean scores for Personal Control (24.5) and Treatment Control (30.2) subscales indicated strongly held positive beliefs in relation to controllability of the illness. Total MET-min/week score was not related to any psychological variables. Analysis of the IPQ-R data revealed 'diet' (n=37, 80.4%) as the most referred to cause of diabetes. Exercise belief data identified "managing weight gain" (n= 21, 45.7%), and "losing baby weight" (n= 31, 67.4%) as the most frequent beliefs for engaging in physical activity during pregnancy and post pregnancy. Further research on the psychological determinants of physical activity behaviour among this population group is needed in order to create successful intervention strategies.


Subject(s)
Diabetes, Gestational/psychology , Exercise/psychology , Health Knowledge, Attitudes, Practice , Cross-Sectional Studies , Diet , Female , Health Behavior , Humans , Pregnancy , Weight Gain
6.
Sci Rep ; 6: 34639, 2016 10 06.
Article in English | MEDLINE | ID: mdl-27708407

ABSTRACT

No systems have been reported for genetic manipulation of cold-adapted Archaea. Halorubrum lacusprofundi is an important member of Deep Lake, Antarctica (~10% of the population), and is amendable to laboratory cultivation. Here we report the development of a shuttle-vector and targeted gene-knockout system for this species. To investigate the function of acetamidase/formamidase genes, a class of genes not experimentally studied in Archaea, the acetamidase gene, amd3, was disrupted. The wild-type grew on acetamide as a sole source of carbon and nitrogen, but the mutant did not. Acetamidase/formamidase genes were found to form three distinct clades within a broad distribution of Archaea and Bacteria. Genes were present within lineages characterized by aerobic growth in low nutrient environments (e.g. haloarchaea, Starkeya) but absent from lineages containing anaerobes or facultative anaerobes (e.g. methanogens, Epsilonproteobacteria) or parasites of animals and plants (e.g. Chlamydiae). While acetamide is not a well characterized natural substrate, the build-up of plastic pollutants in the environment provides a potential source of introduced acetamide. In view of the extent and pattern of distribution of acetamidase/formamidase sequences within Archaea and Bacteria, we speculate that acetamide from plastics may promote the selection of amd/fmd genes in an increasing number of environmental microorganisms.


Subject(s)
Amidohydrolases/genetics , Archaeal Proteins/genetics , Gene Expression Regulation, Archaeal , Genetic Vectors/chemistry , Halorubrum/genetics , Amidohydrolases/deficiency , Antarctic Regions , Archaeal Proteins/metabolism , Biodegradation, Environmental , Culture Media/chemistry , Culture Media/pharmacology , Gene Deletion , Genetic Engineering , Genetic Vectors/metabolism , Halorubrum/classification , Halorubrum/drug effects , Halorubrum/enzymology , Humans , Phylogeny , Plastics/metabolism , Restriction Mapping , Transformation, Genetic , Water Pollutants, Chemical/metabolism
7.
Eur J Cancer Care (Engl) ; 25(1): 49-56, 2016 Jan.
Article in English | MEDLINE | ID: mdl-26087280

ABSTRACT

This study aimed to examine the sensory descriptors used by women undergoing their first ever colposcopy examination as part of cervical cancer screening. Immediately following colposcopy, women were asked to provide detailed information about the sensory, affective, evaluative and intensity properties of the colposcopy examination using a validated, standardised questionnaire. Overall, 160 colposcopy patients with different management options were assessed [53 women underwent diagnostic colposcopy only, 76 had colposcopy plus punch biopsy, 31 women had colposcopy plus see-and-treat large loop excision of the transformation zone (LLETZ) treatment]. The results demonstrated that women report greater pain intensity with more intensive management options, such that women who have punch biopsy or LLETZ treatment report significantly more pain than women who have diagnostic colposcopy. In addition, with increasing intensity of treatment, the number of qualitative sensory and pain descriptors increase. This information can usefully be incorporated into colposcopy information leaflets, to ensure the sensory and affective experience of colposcopy is fully explained to women prior to attending. Expanding the preparatory information that women receive may serve to reduce anxiety, pain and distress associated with colposcopy.


Subject(s)
Colposcopy/psychology , Pain/psychology , Uterine Cervical Neoplasms/diagnosis , Adult , Aged , Analysis of Variance , Anxiety/psychology , Colposcopy/methods , Female , Humans , Middle Aged , Prospective Studies , Qualitative Research , Surveys and Questionnaires , Uterine Cervical Neoplasms/psychology
8.
Eur J Pain ; 16(6): 890-900, 2012 Jul.
Article in English | MEDLINE | ID: mdl-22337343

ABSTRACT

Few studies have compared the relative efficacy of attention-focus strategies in reducing clinical pain. Colposcopy, a medical diagnostic examination performed to identify premalignant cervical cell changes, elicits both anxiety and pain in patients, while allowing little or no behavioural control over the event. Employing a multi-group experimental design, the present study sought to investigate how different types of attention-focus strategies impacted upon pain perception, state anxiety and affect, in a sample of 123 colposcopy patients. Patients were randomly assigned to one of three groups: sensory focusing, active distraction and undirected control. Psychometric measures of pre-colposcopy pain expectancy and dispositional trait anxiety were also taken, in order to assess whether these factors further contributed to outcomes. Overall, when controlling for pain expectancy and trait anxiety, self-reported pain intensity, sensory pain and affective pain did not differ across groups. Further, there were no significant between-group differences in colposcopy-related state anxiety or affect. However, pre-colposcopy psychometric measures were found to be predictive of a range of outcomes. Pre-colposcopy pain expectancy, but not trait anxiety, was found to be positively related to colposcopy-related pain. It was further demonstrated that heightened state anxiety following colposcopy was due to experienced pain and pain unpleasantness, rather than to aspects of the pre-colposcopy prediction of pain. The results have implications for management of acute clinical pain.


Subject(s)
Acute Pain/prevention & control , Anxiety/prevention & control , Attention/physiology , Colposcopy/adverse effects , Pain Management/methods , Acute Pain/psychology , Adult , Anxiety/psychology , Colposcopy/psychology , Female , Humans , Pain Threshold/psychology , Perception , Psychometrics/methods , Young Adult
9.
Eur J Cancer Care (Engl) ; 21(4): 469-76, 2012 Jul.
Article in English | MEDLINE | ID: mdl-22129200

ABSTRACT

Women experience significant emotional distress in relation to further diagnostic evaluation of pre-cancerous cell changes of the cervix. However, less is known about the specific variables that contribute to elevated state anxiety and negative affect prior to colposcopy. The study aims to identify psychosocial factors that predict distress in this patient group, which can help in the development of more sophisticated interventions to reduce psychological distress. Socio-demographic variables, scores for state anxiety, negative affect, trait anxiety, fear of pain, coping style, pain-related expectancy and knowledge were assessed in 164 first-time colposcopy patients immediately before the colposcopy examination. Twenty-six per cent of variance in pre-colposcopy state anxiety was significantly explained by marital status, parity, trait anxiety, fear of minor pain and expectations of discomfort. Twenty-nine per cent of variance in pre-colposcopy negative affect was significantly explained by trait anxiety and expectations of pain. Women who are single, have children, are high trait anxious, and anticipate pain and discomfort appear to be at risk for pre-colposcopy distress. Interventions aimed at reducing pre-colposcopy psychological distress should include situation-specific variables that are amenable to change, and trait anxious women are likely to benefit from interventions to reduce distress.


Subject(s)
Anxiety/prevention & control , Colposcopy/psychology , Adaptation, Psychological , Adult , Affect , Cross-Sectional Studies , Fear/psychology , Female , Humans , Ireland , Multivariate Analysis , Pain/etiology , Risk Factors , Stress, Psychological/etiology , Stress, Psychological/prevention & control , Surveys and Questionnaires , Uterine Cervical Neoplasms/diagnosis , Uterine Cervical Neoplasms/psychology
10.
J Bone Joint Surg Br ; 93(2): 266-8, 2011 Feb.
Article in English | MEDLINE | ID: mdl-21282770

ABSTRACT

We describe a case of bilateral weakness of the lower limbs, sensory disturbance and intermittent urinary incontinence, secondary to untreated Gitelman's syndrome, in a 42-year-old female who was referred with presumed cauda equina syndrome. On examination, the power of both legs was uniformly reduced, and the perianal and lower-limb sensation was altered. However, MRI of the lumbar spine was normal. Measurements of serum and urinary potassium were low and blood gas analysis revealed metabolic alkalosis. Her symptoms resolved following potassium replacement. We emphasise the importance of measurement of the plasma and urinary levels of electrolytes in the investigation of patients with paralysis of the lower limbs and suggest that they, together with blood gas analysis, allow the exclusion of unusual causes of muscle weakness resulting from metabolic disorders such as metabolic alkalosis.


Subject(s)
Gitelman Syndrome/diagnosis , Polyradiculopathy/diagnosis , Adult , Diagnosis, Differential , Female , Humans , Potassium/blood , Potassium/urine
11.
Ir J Med Sci ; 180(1): 285-6, 2011 Mar.
Article in English | MEDLINE | ID: mdl-20886306

ABSTRACT

A 67-year-old patient was admitted for incision and drainage of a recurrent methicillin-resistant Staphylococcus aureus (MRSA) hip abscess. Linezolid therapy was initiated postoperatively. Within 48 h the patient developed confusion, agitation, hypertension and acute renal failure. Citalopram was stopped and resolution of symptoms occurred within 48 h of discontinuing the offending agent. The symptoms observed in our patient were consistent with the Sternbach criteria for serotonin syndrome.


Subject(s)
Abscess/microbiology , Acetamides/adverse effects , Anti-Infective Agents/adverse effects , Hip Joint/microbiology , Methicillin-Resistant Staphylococcus aureus , Oxazolidinones/adverse effects , Prosthesis-Related Infections/drug therapy , Serotonin Syndrome/chemically induced , Staphylococcal Infections/drug therapy , Acetamides/therapeutic use , Aged , Anti-Infective Agents/therapeutic use , Humans , Linezolid , Male , Methicillin-Resistant Staphylococcus aureus/drug effects , Oxazolidinones/therapeutic use , Prosthesis-Related Infections/microbiology , Recurrence
12.
Foot Ankle Surg ; 16(3): e51-4, 2010 Sep.
Article in English | MEDLINE | ID: mdl-20654999

ABSTRACT

We report a case of alveolar rhabdomyosarcoma arising between the fourth and fifth metatarsal. A 13-year-old boy presented to outpatients with a history of pain and swelling in the lateral aspect of his left forefoot. Plain radiographs and MRI showed a soft tissue mass displacing the fourth metatarsal. Percutaneous biopsy revealed an alveolar rhabdomyosarcoma. Staging scans showed advanced metastatic disease. The patient was treated with chemotherapy. This highly malignant lesion remains challenging to diagnose, and difficult to treat successfully.


Subject(s)
Metatarsus , Rhabdomyosarcoma, Alveolar/diagnosis , Adolescent , Biopsy , Diagnosis, Differential , Follow-Up Studies , Humans , Magnetic Resonance Imaging , Male , Positron-Emission Tomography
13.
Gait Posture ; 31(3): 351-4, 2010 Mar.
Article in English | MEDLINE | ID: mdl-20116253

ABSTRACT

Eighteen children with diplegic cerebral palsy and no history of orthopaedic surgery had two gait analyses a mean of 6.3 years apart to analyse the effects of time on their gait. The mean age of the children at first analysis was 7.7 years (range 4.4-13.3 years). The data was analysed as a whole group (18 children) and as two sub-groups of nine children: those with a shorter follow-up (mean 5.0 years) and those with a longer follow-up (mean 7.5 years) between analyses. The following significant bilateral changes were seen in the whole group and longer follow-up sub-group: deterioration in the range of knee flexion, mid-stance knee flexion, peak knee extension in stance and hamstring length and an improvement in mean and maximum hip rotation. Temporal data showed no significant changes once normalised. There were no bilateral significant changes in data from children evaluated at a mean of 5 years follow-up. GMFCS scores generally improved over time despite the significant increase in flexed knee gait. There was no significant change in gait deviation index in any group over time. There was an increase in body mass index in 16 children but there was no correlation between this and the degree of mid-stance knee flexion. These findings may have implications for longer term follow-up of children with cerebral palsy into adulthood.


Subject(s)
Cerebral Palsy/physiopathology , Gait Disorders, Neurologic/physiopathology , Knee Joint/physiopathology , Muscle Spasticity/physiopathology , Adolescent , Biomechanical Phenomena , Child , Child, Preschool , Female , Follow-Up Studies , Humans , Imaging, Three-Dimensional , Male
14.
Hip Int ; 16(4): 299-300, 2006.
Article in English | MEDLINE | ID: mdl-19219809

ABSTRACT

Proprietary femoral plug introducers are routinely used to insert intramedullary plugs during total hip arthroplasty. The cement restrictor pin from an Exeter intramedullary plug introducer may become detached during insertion of the cement restrictor plug, or during sponge packing of the femur. We suggest some precautions that should be taken to prevent this from occurring and advise that the patient is unlikely to experience any long-term adverse reactions to the presence of the restrictor pin in the intramedullary canal.;

15.
Surgeon ; 3(2): 113-6, 2005 Apr.
Article in English | MEDLINE | ID: mdl-15861947

ABSTRACT

A 26-year-old man presented with left leg pain and progressive paraparesis. Imaging revealed a large intradural tumour compressing the cauda equina. The lesion was radically resected and histological analysis revealed it to be a paraganglioma. The clinical features of this rare tumour are described with a review of the literature.


Subject(s)
Cauda Equina , Paraganglioma/diagnosis , Paraganglioma/surgery , Peripheral Nervous System Neoplasms/diagnosis , Peripheral Nervous System Neoplasms/surgery , Adult , Humans , Male
16.
Patient Educ Couns ; 54(1): 61-5, 2004 Jul.
Article in English | MEDLINE | ID: mdl-15210261

ABSTRACT

This study was designed to examine the effects of preparatory information and behavioural training on patients about to undergo an endoscopy procedure. Forty-five first-time endoscopy patients (aged 20-70 years), were randomly assigned to one of three groups (cognitive, cognitive/behavioural and control group). The cognitive group received a 12 min preparation with sensory and procedural information relating to the sensations and sequence of events associated with the endoscopy procedure. The cognitive/behavioural group received, in addition, instruction in deep breathing exercises, tongue depressor task and swallowing technique. Results indicated that patients in the two experimental conditions experienced significantly fewer signs of behavioural distress during endoscopy. The cognitive group required a significantly shorter time to induce the scope. There were no statistical differences between the groups however, for mood, physiological and anxiety measures, although a positive trend was evident for the two intervention groups.


Subject(s)
Cognitive Behavioral Therapy , Endoscopy, Gastrointestinal , Patient Education as Topic/standards , Relaxation Therapy , Adult , Affect , Aged , Analysis of Variance , Anxiety/etiology , Anxiety/prevention & control , Anxiety/psychology , Breathing Exercises , Cognitive Behavioral Therapy/education , Cognitive Behavioral Therapy/standards , Endoscopy, Gastrointestinal/adverse effects , Endoscopy, Gastrointestinal/psychology , Humans , Middle Aged , Program Evaluation , Prospective Studies , Relaxation Therapy/education , Relaxation Therapy/standards , Stress, Psychological/etiology , Stress, Psychological/prevention & control , Stress, Psychological/psychology , Time Factors , Treatment Outcome
17.
AIDS Care ; 14(3): 329-34, 2002 Jun.
Article in English | MEDLINE | ID: mdl-12042078

ABSTRACT

The aim of this study was to examine current approaches to supporting adherence to antiretroviral therapy in UK HIV clinics. One hundred HIV/AIDS/GUM physicians were interviewed: 97% were personally involved in discussing adherence, spending 22% of consultation time on this issue and assessing adherence most commonly by patient self-report (88%). Other personnel involved included nurses (74%), other doctors (56%), health advisers (54%) and pharmacists (48%). Among criteria for achieving treatment success, adherence support ranked fourth after 'treatment fitting well into patient's lifestyle', regular viral load monitoring and the 'experience of the clinician/healthcare team'. A variety of tools were used to support adherence including dosette boxes (53%), written information (44%) and verbal communication (42%). Only 20% of physicians followed adherence protocols or formal guidelines. Three-quarters of physicians had received no training on adherence issues. The most common ways physicians kept informed about adherence matters were by attending conferences (87%), reading literature (71%) and learning from colleagues (51%). Eighty-seven per cent of physicians believed national adherence guidelines would be valuable. In conclusion, there is a need for training and direction within current adherence support services. National guidelines could provide a valuable framework for health care professionals.


Subject(s)
Antiretroviral Therapy, Highly Active/statistics & numerical data , HIV Infections/drug therapy , Patient Compliance/statistics & numerical data , Ambulatory Care/statistics & numerical data , Attitude of Health Personnel , Education, Medical, Continuing/methods , Humans , State Medicine , United Kingdom
18.
AIDS Care ; 13(6): 709-20, 2001 Dec.
Article in English | MEDLINE | ID: mdl-11720641

ABSTRACT

The objective of the study was to define common reasons for non-adherence (NA) to highly active antiretroviral therapy (HAART) and the number of reasons reported by non-adherent individuals. A confidential questionnaire was administered to HIV-seropositive patients taking proteinase inhibitor based HAART. Median self-reported adherence was 95% (n = 178, range = 60-100%). The most frequent reasons for at least 'sometimes' missing a dose were eating a meal at the wrong time (38.2%), oversleeping (36.3%), forgetting (35.0%) and being in a social situation (30.5%). The mean number of reasons occurring at least 'sometimes' was 3.2; 20% of patients gave six or more reasons; those reporting the lowest adherence reported a significantly greater numbers of reasons (rho = - 0.59; p < 0.001). Three factors were derived from the data by principal component analysis reflecting 'negative experiences of HAART', 'having a low priority for taking medication' and 'unintentionally missing doses', accounting for 53.8% of the variance. On multivariate analysis only the latter two factors were significantly related to NA (odds ratios 0.845 and 0.849, respectively). There was a wide spectrum of reasons for NA in our population. The number of reasons in an individual increased as adherence became less. A variety of modalities individualized for each patient are required to support patients with the lowest adherence.


Subject(s)
Antiretroviral Therapy, Highly Active/adverse effects , HIV Seropositivity/drug therapy , HIV Seropositivity/psychology , Treatment Refusal , Acquired Immunodeficiency Syndrome/drug therapy , Acquired Immunodeficiency Syndrome/psychology , Adult , Female , Humans , Male , Mental Recall , Multivariate Analysis , Odds Ratio , Surveys and Questionnaires
19.
J Org Chem ; 66(7): 2265-74, 2001 Apr 06.
Article in English | MEDLINE | ID: mdl-11281765

ABSTRACT

Chromium tricarbonyl complexed aryl aldeyhydes and ketones underwent Sm(II)-promoted radical lactone formation in the presence of alpha,beta-unsaturated esters to produce diastereomerically pure lactones in good yields. The completely diastereoselective lactone formation involves capture of the benzylic ketyl radical by the ester anti to the chromium tricarbonyl moiety. The relative stereochemistry of the lactone and chromium tricarbonyl moieties was proven by X-ray crystallography and supports the proposed mechanism. Enantiopure chromium tricarbonyl complexed arenes afforded single enantiomers when subjected to Sm(II)-promoted radical lactone formation condiditions. The enantio- and diastereomerically pure chromium tricarbonyl complexed lactones were subsequently treated with BF3.OEt2 to generate a mixture of diastereomers via Lewis acid promoted chromium tricabonyl directed cationic rearrangement. The diastereomers were separated and individually decomplexed with I2 to afford both of the corresponding chromium-free enantiomerically pure lactones starting from a single enantiomerically pure chromium tricarbonyl complex.

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