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2.
Hong Kong Med J ; 29(6): 514-523, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37968897

ABSTRACT

INTRODUCTION: The utilisation of extracorporeal membrane oxygenation (ECMO) has been rapidly increasing in Hong Kong. This study examined 10-year trends in the utilisation and clinical outcomes of ECMO in Hong Kong. METHODS: We retrospectively reviewed the records of all adult patients receiving ECMO who were admitted to the intensive care units (ICUs) of public hospitals in Hong Kong between 2010 and 2019. Temporal trends across years were assessed using the Mann-Kendall test. Observed hospital mortality was compared with the Acute Physiology and Chronic Health Evaluation (APACHE) IV-predicted mortality. RESULTS: The annual number of patients receiving ECMO increased from 18 to 171 over 10 years. In total, 911 patients received ECMO during the study period: 297 (32.6%) received veno-arterial ECMO, 450 (49.4%) received veno-venous ECMO, and 164 (18.0%) received extracorporeal cardiopulmonary resuscitation. The annual number of patients aged ≥65 years increased from 0 to 47 (27.5%) [P for trend=0.001]. The median (interquartile range) Charlson Comorbidity Index increased from 1 (0-1) to 2 (1-3) [P for trend<0.001] while the median (interquartile range) APACHE IV score increased from 90 (57-112) to 105 (77-137) [P for trend=0.003]. The overall standardised mortality ratio comparing hospital mortality with APACHE IV-predicted mortality was 1.11 (95% confidence interval=1.01-1.22). Hospital and ICU length of stay both significantly decreased (P for trend=0.011 and <0.001, respectively). CONCLUSION: As ECMO utilisation increased in Hong Kong, patients put on ECMO were older, more critically ill, and had more co-morbidities. It is important to combine service expansion with adequate resource allocation and training to maintain quality of care.


Subject(s)
Cardiopulmonary Resuscitation , Extracorporeal Membrane Oxygenation , Adult , Humans , Hong Kong , Retrospective Studies , APACHE
5.
Int Nurs Rev ; 66(4): 514-522, 2019 Dec.
Article in English | MEDLINE | ID: mdl-31184377

ABSTRACT

BACKGROUND: The ageing population and the changing disease profile have been driving the demand for community nurses. However, few nursing students in Singapore aspire to have a career in community nursing following graduation. OBJECTIVES: To explore undergraduate nursing students' perceptions of a career in community nursing and to identify strategies to promote community nursing among nursing students. METHODS: An exploratory qualitative design was used. Four focus group discussions were conducted with a purposive sample of 24 undergraduate nursing students from a university. Interview transcripts were analysed using thematic analysis. FINDINGS: Four key themes emerged as follows: 'mid-life career', 'limited career progression', 'a difficult transition' and 'international nurses-dominated workforce'. DISCUSSION: While most participants rejected a career in community nursing immediately after graduation, they planned to join it at the later stages of their lives to accommodate changing life priorities. Limited career progression and increased difficulty in career transition from community nursing to acute care nursing were identified as deterrent factors in the participants' choices of community nursing as a career. Feelings of marginalization and a lack of role models in community nursing were perceived to be the result of the international nurses-dominated community workforce. CONCLUSION: Community nursing remains an underrated career. There is a need to foster an optimistic career outlook and mobility in community nursing to entice nursing students into this career track. IMPLICATIONS FOR NURSING POLICY: Strategies to enhance community nursing recruitment should focus on providing more quality and diverse community placement opportunities in various community care settings, implementing a clearly defined career developmental plan to elucidate the role of community nurses, and improving community care and cultural competencies to develop a skilled and diverse community nursing workforce.


Subject(s)
Career Choice , Community Health Nursing/education , Students, Nursing/psychology , Career Mobility , Education, Nursing, Baccalaureate , Female , Focus Groups , Humans , Male , Qualitative Research , Singapore , Young Adult
6.
Anaesthesia ; 73(9): 1067-1078, 2018 Sep.
Article in English | MEDLINE | ID: mdl-29974459

ABSTRACT

Inappropriate dosing of neostigmine for antagonism of neuromuscular blockade has been associated with postoperative pulmonary complications. We evaluated the effects of a quality improvement initiative tailored to optimise the use of neostigmine in antagonising neuromuscular blockade on postoperative pulmonary complications, costs and duration of hospital stay. The quality improvement initiative consisted of: a reduction in available neostigmine aliquot sizes; a cognitive aid; an educational component; and a financial incentive for the intra-operative documentation of train-of-four measurement before administration of neostigmine. We conducted a pre-specified analysis of data obtained in our quality improvement study. Additional analyses were conducted in a propensity-matched cohort. An interrupted time series design was used to discriminate between the intervention and a counterfactual scenario. We analysed 12,025 consecutive surgical cases performed in 2015. Postoperative pulmonary complications occurred in 220 (7.5%) of 2937 cases pre-intervention and 568 (6.3%) of 9088 cases post-intervention. Adjusted regression analyses showed significantly a lower risk of postoperative pulmonary complications (OR 0.73 (95%CI 0.61-0.88); p = 0.001), lower costs (incidence rate ratio 0.95 (95%CI 0.93-0.97); p < 0.001) and shorter duration of hospital stay (incidence rate ratio 0.91 (95%CI 0.87-0.94); p < 0.001) after implementation of the quality improvement initiative. Analyses in a propensity-matched sample (n = 2936 per group) and interrupted time series analysis (n = 27,202 cases) confirmed the findings. Our data show that a local, multifaceted quality improvement initiative can enhance the quality of intra-operative neuromuscular blocking agent utilisation, thereby reducing the incidence of postoperative pulmonary complications.


Subject(s)
Cholinesterase Inhibitors/administration & dosage , Lung Diseases/prevention & control , Neostigmine/administration & dosage , Neuromuscular Blockade/methods , Postoperative Complications/prevention & control , Adult , Aged , Cholinesterase Inhibitors/adverse effects , Cholinesterase Inhibitors/pharmacology , Dose-Response Relationship, Drug , Female , Hospital Costs/statistics & numerical data , Humans , Length of Stay/statistics & numerical data , Lung Diseases/chemically induced , Lung Diseases/epidemiology , Male , Massachusetts/epidemiology , Middle Aged , Neostigmine/adverse effects , Neostigmine/pharmacology , Neuromuscular Blockade/economics , Neuromuscular Junction/drug effects , Perioperative Care/methods , Postoperative Complications/chemically induced , Postoperative Complications/epidemiology , Prospective Studies , Quality Improvement/organization & administration , Young Adult
7.
Med J Malaysia ; 73(1): 41-43, 2018 02.
Article in English | MEDLINE | ID: mdl-29531201

ABSTRACT

Procidentia is uncommon condition altering quality of life of young and nulliparous women. Its management poses significant dilemma and challenges as its associated body image, fertility and sexuality issues. Uterine preservation surgery described by Archibald Donald in 1888 known as Manchester -Fothergill procedure seems best option as alternative to vaginal hysterectomy. Despite its increasing popularity among surgeons and patients, robust clinical evidence is needed. We report a case of recurrent procidentia in a young nulliparous woman who had Manchester repair following vaginal sacrospinous hysteropexy. We concluded that Manchester repair is a useful and safe alternative for uterine-preserving technique.


Subject(s)
Uterine Prolapse/surgery , Uterus/surgery , Adult , Female , Humans , Recurrence , Tomography, X-Ray Computed , Ultrasonography , Uterine Prolapse/diagnostic imaging , Uterus/diagnostic imaging
8.
Anaesthesia ; 72(11): 1334-1343, 2017 Nov.
Article in English | MEDLINE | ID: mdl-28891046

ABSTRACT

We thought that the rate of postoperative pulmonary complications might be higher after pressure-controlled ventilation than after volume-controlled ventilation. We analysed peri-operative data recorded for 109,360 adults, whose lungs were mechanically ventilated during surgery at three hospitals in Massachusetts, USA. We used multivariable regression and propensity score matching. Postoperative pulmonary complications were more common after pressure-controlled ventilation, odds ratio (95%CI) 1.29 (1.21-1.37), p < 0.001. Tidal volumes and driving pressures were more varied with pressure-controlled ventilation compared with volume-controlled ventilation: mean (SD) variance from the median 1.61 (1.36) ml.kg-1 vs. 1.23 (1.11) ml.kg-1 , p < 0.001; and 3.91 (3.47) cmH2 O vs. 3.40 (2.69) cmH2 O, p < 0.001. The odds ratio (95%CI) of pulmonary complications after pressure-controlled ventilation compared with volume-controlled ventilation at positive end-expiratory pressures < 5 cmH2 O was 1.40 (1.26-1.55) and 1.20 (1.11-1.31) when ≥ 5 cmH2 O, both p < 0.001, a relative risk ratio of 1.17 (1.03-1.33), p = 0.023. The odds ratio (95%CI) of pulmonary complications after pressure-controlled ventilation compared with volume-controlled ventilation at driving pressures of < 19 cmH2 O was 1.37 (1.27-1.48), p < 0.001, and 1.16 (1.04-1.30) when ≥ 19 cmH2 O, p = 0.011, a relative risk ratio of 1.18 (1.07-1.30), p = 0.016. Our data support volume-controlled ventilation during surgery, particularly for patients more likely to suffer postoperative pulmonary complications.


Subject(s)
Lung Diseases/epidemiology , Postoperative Complications/epidemiology , Respiration, Artificial/adverse effects , Adult , Aged , Air Pressure , Female , Humans , Intermittent Positive-Pressure Ventilation , Lung Diseases/etiology , Lung Volume Measurements , Male , Middle Aged , Odds Ratio , Positive-Pressure Respiration , Propensity Score , Respiration, Artificial/statistics & numerical data , Risk Assessment , Risk Factors , Tidal Volume
9.
Comput Math Methods Med ; 2017: 2610628, 2017.
Article in English | MEDLINE | ID: mdl-28473865

ABSTRACT

Medical imaging techniques have widely been in use in the diagnosis and detection of breast cancer. The drawback of applying these techniques is the large time consumption in the manual diagnosis of each image pattern by a professional radiologist. Automated classifiers could substantially upgrade the diagnosis process, in terms of both accuracy and time requirement by distinguishing benign and malignant patterns automatically. Neural network (NN) plays an important role in this respect, especially in the application of breast cancer detection. Despite the large number of publications that describe the utilization of NN in various medical techniques, only a few reviews are available that guide the development of these algorithms to enhance the detection techniques with respect to specificity and sensitivity. The purpose of this review is to analyze the contents of recently published literature with special attention to techniques and states of the art of NN in medical imaging. We discuss the usage of NN in four different medical imaging applications to show that NN is not restricted to few areas of medicine. Types of NN used, along with the various types of feeding data, have been reviewed. We also address hybrid NN adaptation in breast cancer detection.


Subject(s)
Breast Neoplasms/diagnostic imaging , Early Detection of Cancer , Image Processing, Computer-Assisted/methods , Neural Networks, Computer , Algorithms , Humans , Image Processing, Computer-Assisted/standards , Sensitivity and Specificity
10.
Epidemiol Infect ; 144(12): 2540-5, 2016 09.
Article in English | MEDLINE | ID: mdl-27174845

ABSTRACT

Prevalence of vancomycin-resistant enterococci (VRE) and use of daptomycin are increasing in Asia. To determine the prevalence of daptomycin non-susceptible enterococci (DNSE) and understand factors associated with reduced daptomycin susceptibility in VRE, we conducted a case-control study in a 1600-bed adult tertiary hospital in Singapore. All VRE isolates from inpatients in 2012 were tested for daptomycin susceptibility. Patients with VRE isolates of daptomycin minimum inhibitory concentration (MIC) ⩾3 µg/ml were classified as daptomycin-reduced susceptible VRE (DRS-VRE) and those with daptomycin MIC 4 µg/ml (DNSE). About half (135, 55%) had reduced susceptibility to daptomycin (MIC 3-4 µg/ml). None in the DS-VRE group had prior exposure to daptomycin. After adjusting for age, gender, comorbidity, hospitalization duration, surgical history, indwelling device use, and duration of antibiotic exposure in the prior 3 months, >1 movement between wards [odds ratio (OR) 0·35, 95% confidence interval (CI) 0·16-0·74, P = 0·006] and minocycline resistance (OR 0·45, 95% CI 0·25-0·84, P = 0·011) were independently associated with DRS-VRE. Our study suggests that daptomycin exposure, >1 movement between wards, and resistance to minocycline, were associated with reduced daptomycin susceptibility in VRE.


Subject(s)
Anti-Bacterial Agents/pharmacology , Daptomycin/pharmacology , Gram-Positive Bacterial Infections/epidemiology , Vancomycin Resistance , Vancomycin-Resistant Enterococci/drug effects , Vancomycin-Resistant Enterococci/physiology , Aged , Aged, 80 and over , Case-Control Studies , Female , Gram-Positive Bacterial Infections/microbiology , Humans , Male , Middle Aged , Prevalence , Risk , Singapore/epidemiology , Tertiary Care Centers
11.
Eur J Obstet Gynecol Reprod Biol ; 198: 110-115, 2016 Mar.
Article in English | MEDLINE | ID: mdl-26808667

ABSTRACT

OBJECTIVE: To determine the prevalence of urinary incontinence among primigravida in the third trimester, its risk factors and its effect to quality of life. STUDY DESIGN: This is a cross sectional study involving primigravida in their third trimester of pregnancy, who attended the Patient Assessment Centre of a tertiary referral hospital in Klang Valley from July 2012 to June 2013. The participants were chosen randomly using convenience sampling. A face-to-face interview and a review of their antenatal record were done by trained interviewers. Data on sociodemographic and risk factors were obtained followed by the International Consultation on Incontinence Questionnaire - Short Form (ICIQ-SF). The data was analysed using Statistical Package for Social Science version 20.0. RESULTS: A total of 306 women were involved. The prevalence of urinary incontinence during third trimester was 34.3% (95%CI: 29.0, 39.7). Stress incontinence (64.8%) is the commonest followed by mixed incontinence (24.8%) and urge incontinence (6.7%). Childhood enuresis (p=0.003) and previous history of urinary incontinence (p<0.001) were significantly associated with urinary incontinence. More than 50 percent of women with urinary incontinence in the third trimester felt that it did not affect their daily activities at all. Only 10% of women felt greatly affected by this problem. CONCLUSION: Urinary incontinence is not uncommon among primigravida however many women did not feel that it affected their quality of life. Childhood enuresis and history of urinary incontinence were proven risk factors.


Subject(s)
Gravidity , Pregnancy Complications/etiology , Urinary Incontinence, Urge/etiology , Adult , Body Mass Index , Cross-Sectional Studies , Female , Humans , Pregnancy , Pregnancy Trimester, Third , Risk Factors
12.
Epidemiol Infect ; 144(6): 1248-56, 2016 Apr.
Article in English | MEDLINE | ID: mdl-26538070

ABSTRACT

Hospital-acquired methicillin-resistant Staphylococcus aureus (HA-MRSA) is becoming increasingly established in Asian hospitals. The primary aim of this study was to decompose the risk factors for HA-MRSA based on conceptual clinical pathways. The secondary aim was to show the amount of effect attributable to antibiotic exposure and total length of stay before outcome (LBO) so that institutions can manage at-risk patients accordingly. A case-control study consisting of 1200 inpatients was conducted in a large tertiary hospital in Singapore between January and December 2006. Results from the generalized structural equation model (GSEM) show that LBO [adjusted odds ratio (aOR) 14·9, 95% confidence interval (CI) 8·7-25·5], prior hospitalization (aOR 6·2, 95% CI 3·3-11·5), and cumulative antibiotic exposure (aOR 3·5, 95% CI 2·3-5·3), directly affected HA-MRSA acquisition. LBO accounted for the majority of the effects due to age (100%), immunosuppression (67%), and surgery (96%), and to a lesser extent for male gender (22%). Our model enabled us to account and quantify effects of intermediaries. LBO was found to be an important mediator of age, immunosuppression and surgery on MRSA infection. Traditional regression approaches will not only give different conclusions but also underestimate the effects. Hospitals should minimize the hospital stay when possible to reduce the risk of MRSA.


Subject(s)
Cross Infection/epidemiology , Length of Stay , Methicillin-Resistant Staphylococcus aureus/physiology , Staphylococcal Infections/epidemiology , Adult , Aged , Aged, 80 and over , Case-Control Studies , Cross Infection/microbiology , Female , Humans , Male , Methicillin-Resistant Staphylococcus aureus/drug effects , Middle Aged , Risk Factors , Singapore/epidemiology , Staphylococcal Infections/microbiology
13.
Pharmazie ; 71(8): 427-433, 2016 08 01.
Article in English | MEDLINE | ID: mdl-29442028

ABSTRACT

Bone diseases such as osteoporosis, osteoarthritis, bone tumours and bone fractures are rather common and not just in the elderly. Parathyroid hormone (PTH) is responsible for maintaining calcium homeostasis, increasing bone mineral density (BMD), increasing cortical and trabecular bone thickness and thus increasing bone strength. Teriparatide (PTH 1-34) has the same effects as endogenous PTH and is pharmacologically used to treat bone diseases such as osteoporosis, osteoarthritis, bone fractures and bone tumours. This review discusses how PTH 1-34 plays a role in managing bone diseases. Clinical studies have shown that short or intermittent dosing of PTH 1-34 has minimal adverse effects, while long-term dosing (over two years) has been linked to de novo osteoarthritis and bone deformation. Currently PTH therapy is only approved in the treatment of post-menopausal osteoporosis, however it is also proven to have effects in treating osteoarthritis, bone tumours and bone fractures. If the patient undergoing therapy is closely monitored, the major pitfalls are very unlikely to take place, thus it is highly recommended that patients be closely monitored by a medical practitioner.


Subject(s)
Bone Diseases/drug therapy , Parathyroid Hormone/adverse effects , Parathyroid Hormone/therapeutic use , Aged , Bone Density Conservation Agents/therapeutic use , Diphosphonates/therapeutic use , Humans , Parathyroid Hormone/physiology , Randomized Controlled Trials as Topic , Treatment Outcome
14.
Oncogene ; 31(15): 1949-62, 2012 Apr 12.
Article in English | MEDLINE | ID: mdl-21909130

ABSTRACT

The phosphatidylinositol 3-kinase (PI3K)/AKT and RAS oncogenic signalling modules are frequently mutated in sporadic human cancer. Although each of these pathways has been shown to play critical roles in driving tumour growth and proliferation, their activation in normal human cells can also promote cell senescence. Although the mechanisms mediating RAS-induced senescence have been well characterised, those controlling PI3K/AKT-induced senescence are poorly understood. Here we show that PI3K/AKT pathway activation in response to phosphatase and tensin homolog (PTEN) knockdown, mutant PI3K, catalytic, α polypeptide (PIK3CA) or activated AKT expression, promotes accumulation of p53 and p21, increases cell size and induces senescence-associated ß-galactosidase activity. We demonstrate that AKT-induced senescence is p53-dependent and is characterised by mTORC1-dependent regulation of p53 translation and stabilisation of p53 protein following nucleolar localisation and inactivation of MDM2. The underlying mechanisms of RAS and AKT-induced senescence appear to be distinct, demonstrating that different mediators of senescence may be deregulated during transformation by specific oncogenes. Unlike RAS, AKT promotes rapid proliferative arrest in the absence of a hyperproliferative phase or DNA damage, indicating that inactivation of the senescence response is critical at the early stages of PI3K/AKT-driven tumourigenesis. Furthermore, our data imply that chronic activation of AKT signalling provides selective pressure for the loss of p53 function, consistent with observations that PTEN or PIK3CA mutations are significantly associated with p53 mutation in a number of human tumour types. Importantly, the demonstration that mTORC1 is an essential mediator of AKT-induced senescence raises the possibility that targeting mTORC1 in tumours with activated PI3K/AKT signalling may exert unexpected detrimental effects due to inactivation of a senescence brake on potential cancer-initiating cells.


Subject(s)
Proteins/metabolism , Proto-Oncogene Proteins c-akt/metabolism , TOR Serine-Threonine Kinases/metabolism , Cell Transformation, Neoplastic/genetics , Cells, Cultured , Cellular Senescence/genetics , DNA Damage , Fibroblasts , Humans , Mechanistic Target of Rapamycin Complex 1 , Multiprotein Complexes , PTEN Phosphohydrolase/genetics , Proteasome Endopeptidase Complex , Proto-Oncogene Proteins c-akt/physiology , Proto-Oncogene Proteins c-mdm2/metabolism , Signal Transduction , Tumor Suppressor Protein p53
15.
Heart Asia ; 1(1): 39-40, 2009.
Article in English | MEDLINE | ID: mdl-27325925

ABSTRACT

The relative role of surgical or endovascular treatment in carotid stenosis remains controversial. Results of recent studies add even more confusion to the debate. Major clinical trials so far have shown a wide range of complication rates for carotid endarterectomy and carotid stenting. Only surgeons or interventionists who can maintain a complication rate of 3% or below should consider treating patients with asymptomatic disease.

16.
Curr Top Med Chem ; 8(17): 1533-44, 2008.
Article in English | MEDLINE | ID: mdl-19075764

ABSTRACT

Over the past ten years, sirtuins have emerged as an important class of drug targets. These enzymes play an important role in gene activation and silencing in all organisms from prokaryotes to humans. There is evidence that sirtuin modulation can be beneficial for a wide variety of diseases associated with aging. Among these conditions are diabetes, neurodegenerative diseases, and cancer. Agents that activate some sirtuins may be beneficial, while inhibitors of other sirtuins might represent treatment options. This review covers the chemical activators and inhibitors of the sirtuins that have appeared in the literature through the first half of 2008.


Subject(s)
Enzyme Inhibitors/therapeutic use , Metabolic Diseases/drug therapy , Sirtuins/antagonists & inhibitors , Diabetes Mellitus, Type 2/drug therapy , Humans , Kinetics , Metabolic Diseases/metabolism , Sirtuins/metabolism
17.
Cell Mol Life Sci ; 64(14): 1739-51, 2007 Jul.
Article in English | MEDLINE | ID: mdl-17415520

ABSTRACT

The biological system is a complex physicochemical system consisting of numerous dynamic networks of biochemical reactions and signaling interactions between cellular components. This complexity makes it virtually unanalyzable by traditional methods. Hence, biological networks have been developed as a platform for integrating information from high- to low-throughput experiments for analysis of biological systems. The network analysis approach is vital for successful quantitative modeling of biological systems. The numerous online pathway databases vary widely in coverage and representation of biological processes. An integrated network-based information system for querying, visualization and analysis promised successful integration of data on a large scale. Such integrated systems will greatly facilitate the understanding of biological interactions and experimental verification.


Subject(s)
Systems Biology/methods , Data Interpretation, Statistical , Databases, Genetic , Internet , Models, Biological , Signal Transduction
18.
Neuroscience ; 124(2): 299-304, 2004.
Article in English | MEDLINE | ID: mdl-14980380

ABSTRACT

The role of nitric oxide (NO) in post-ischemic cerebral infarction has been extensively examined, but few studies have investigated its role on the neurological deficit. In the present study, we investigated the effect of spermine on the temporal evolution of infarct volume, NO production and neurological deficit using magnetic resonance imaging in a model of permanent focal cerebral ischemia in rats. Spermine given at 10 mg/kg 2 h after ischemia reduced the infarct volume by 40% and abolished brain NO production and improved the neurological score 24 h, 48 h and 72 h after ischemia. Spermine also reduced the neurological deficit as evaluated by rotamex, grip strength and neurological severity score tests.


Subject(s)
Behavior, Animal/drug effects , Brain Infarction/prevention & control , Infarction, Middle Cerebral Artery/drug therapy , Magnetic Resonance Imaging , Nervous System Diseases/prevention & control , Spermine/therapeutic use , Analysis of Variance , Animals , Brain Chemistry/drug effects , Brain Infarction/etiology , Brain Infarction/pathology , Brain Mapping , Disease Models, Animal , Hand Strength , Hemiplegia/drug therapy , Hemiplegia/etiology , Hemiplegia/physiopathology , Infarction, Middle Cerebral Artery/complications , Infarction, Middle Cerebral Artery/pathology , Male , Nervous System Diseases/etiology , Nitrates/metabolism , Nitrites/metabolism , Paresis/drug therapy , Paresis/etiology , Paresis/physiopathology , Psychomotor Performance/drug effects , Rats , Rats, Sprague-Dawley , Tetrazolium Salts , Time Factors
19.
Clin Radiol ; 57(9): 800-6, 2002 Sep.
Article in English | MEDLINE | ID: mdl-12384105

ABSTRACT

OBJECTIVES: Osmotic myelinolysis is a distinctive clinical syndrome with characteristic CT and MR features. This study was undertaken to determine the MR appearance of these lesions on T1 and T2-weighted, and diffusion-weighted imaging (DWI) sequences with apparent diffusion coefficient (ADC) mapping. MATERIALS AND METHODS: We describe six patients who presented with deranged serum sodium levels and subsequently developed osmotic myelinolysis. CT and MRI scans were retrospectively reviewed, including the advanced functional MR sequence of DWI with ADC mapping. RESULTS: Both cerebral white matter and pontine lesions were typically hypo and hyper-intense on T1 and T2W sequences respectively. Lesions were mildly hyperintense on isotropic DWI images with elevation of the ADC. CONCLUSION: MRI is superior to CT in depicting lesions in osmotic myelinolysis. DWI with ADC mapping suggests that osmotic myelinolysis is not simply a demyelinating disorder but has similarities to multiple sclerosis.


Subject(s)
Magnetic Resonance Imaging , Myelinolysis, Central Pontine/diagnosis , Adult , Diffusion , Female , Humans , Hyponatremia/etiology , Magnetic Resonance Imaging/methods , Male , Middle Aged , Myelinolysis, Central Pontine/complications , Myelinolysis, Central Pontine/diagnostic imaging , Retrospective Studies , Tomography, X-Ray Computed
20.
Eur J Vasc Endovasc Surg ; 23(1): 29-38, 2002 Jan.
Article in English | MEDLINE | ID: mdl-11748945

ABSTRACT

OBJECTIVES: seeding prosthetic grafts with fat-derived microvascular endothelial cells (MVEC) results not only in a non-thrombogenic EC layer, but also in intimal hyperplasia. Here we investigated incidence, composition, progression, and cause of this intimal hyperplasia. DESIGN: EPTFE grafts with MVEC were implanted as carotid interpositions in six dogs with 1 month, and in three dogs with 4, 8 and 12 months follow-up. Grafts seeded without cells, implanted in the contralateral carotid, served as a control. In another three dogs labelled cells were seeded to investigate the contribution of the seeded cells (2-3 weeks). MATERIALS AND METHODS: MVEC were isolated from the falciform ligament. Cells were pressure seeded on ePTFE grafts. Labelling was performed using retroviral gene transduction. The grafts were analysed with immunohistochemical techniques. RESULTS: after 1 month, all patent non-seeded grafts (5/6) showed fibrin and platelet deposition, and all patent seeded grafts (5/6) were covered with a confluent endothelial monolayer on top of a multilayer of myofibroblasts, elastin and collagen. After long term follow-up, all non-seeded grafts were occluded, all patent seeded grafts (4 and 12 months) were covered with an EC-layer with intimal hyperplasia underneath. The thickness of the intima did not progress after 1 month. Transduced cells were found in the endothelial monolayer, hyperplastic intima and luminal part of the prosthesis. CONCLUSIONS: MVEC seeding in dogs results in intimal hyperplasia in all patent grafts, which contains myofibroblasts. Contaminants from the transplant contribute to this intimal hyperplasia.


Subject(s)
Blood Vessel Prosthesis Implantation , Blood Vessel Prosthesis , Endothelium, Vascular/cytology , Graft Occlusion, Vascular/pathology , Tissue Engineering , Tunica Intima/pathology , Animals , Carotid Arteries/surgery , Cells, Cultured , Dogs , Endothelium, Vascular/chemistry , Endothelium, Vascular/pathology , Gene Transfer Techniques , Graft Occlusion, Vascular/physiopathology , Hyperplasia , Immunohistochemistry , Polytetrafluoroethylene , Vascular Patency
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