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1.
Epidemiol Psychiatr Sci ; 29: e29, 2019 Apr 05.
Article in English | MEDLINE | ID: mdl-30947763

ABSTRACT

AIMS: The second Singapore Mental Health Study (SMHS) - a nationwide, cross-sectional, epidemiological survey - was initiated in 2016 with the intent of tracking the state of mental health of the general population in Singapore. The study employed the same methodology as the first survey initiated in 2010. The SMHS 2016 aimed to (i) establish the 12-month and lifetime prevalence and correlates of major depressive disorder (MDD), dysthymia, bipolar disorder, generalised anxiety disorder (GAD), obsessive compulsive disorder (OCD) and alcohol use disorder (AUD) (which included alcohol abuse and dependence) and (ii) compare the prevalence of these disorders with reference to data from the SMHS 2010. METHODS: Door-to-door household surveys were conducted with adult Singapore residents aged 18 years and above from 2016 to 2018 (n = 6126) which yielded a response rate of 69.0%. The subjects were randomly selected using a disproportionate stratified sampling method and assessed using World Health Organization Composite International Diagnostic Interview version 3.0 (WHO-CIDI 3.0). The diagnoses of lifetime and 12-month selected mental disorders including MDD, dysthymia, bipolar disorder, GAD, OCD, and AUD (alcohol abuse and alcohol dependence), were based on the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV) criteria. RESULTS: The lifetime prevalence of at least one mood, anxiety or alcohol use disorder was 13.9% in the adult population. MDD had the highest lifetime prevalence (6.3%) followed by alcohol abuse (4.1%). The 12-month prevalence of any DSM-IV mental disorders was 6.5%. OCD had the highest 12-month prevalence (2.9%) followed by MDD (2.3%). Lifetime and 12-month prevalence of mental disorders assessed in SMHS 2016 (13.8% and 6.4%) was significantly higher than that in SMHS 2010 (12.0% and 4.4%). A significant increase was observed in the prevalence of lifetime GAD (0.9% to 1.6%) and alcohol abuse (3.1% to 4.1%). The 12-month prevalence of GAD (0.8% vs. 0.4%) and OCD (2.9% vs. 1.1%) was significantly higher in SMHS 2016 as compared to SMHS 2010. CONCLUSIONS: The high prevalence of OCD and the increase across the two surveys needs to be tackled at a population level both in terms of creating awareness of the disorder and the need for early treatment. Youth emerge as a vulnerable group who are more likely to be associated with mental disorders and thus targeted interventions in this group with a focus on youth friendly and accessible care centres may lead to earlier detection and treatment of mental disorders.


Subject(s)
Mental Disorders/epidemiology , Adolescent , Adult , Aged , Cross-Sectional Studies , Female , Humans , Male , Mental Health , Middle Aged , Prevalence , Singapore/epidemiology , Young Adult
2.
Bioresour Technol ; 265: 365-371, 2018 Oct.
Article in English | MEDLINE | ID: mdl-29925052

ABSTRACT

In this study, three different methods for high quality solid fuel production were tested and compared experimentally. Oil palm empty fruit bunches, mesocarp fibers, palm kernel shells and rubber seeds shells were treated using thermal (TC), hydrothermal (HTC) and vapothermal (VTC) carbonization. All thermochemical methods were accomplished by using a custom made batch-type reactor. Utilization of novel single reactor equipped with suspended internal container provided efficient operation since both steam generator and raw materials were placed inside the same reactor. Highest energy densification was achieved by VTC process followed by TC and HTC processes. The heating value enhancement in VTC and TC was achieved by the increase in fixed carbon content and reduction in volatile matter. The formation of the spherical components in HTC hydrochar which gave a sharp peak at 340 °C in the DTG curves was suggested as the reason that led to the increment in energy content.


Subject(s)
Agriculture , Carbon , Refuse Disposal , Steam
3.
PLoS One ; 13(1): e0191478, 2018.
Article in English | MEDLINE | ID: mdl-29351554

ABSTRACT

The power system always has several variations in its profile due to random load changes or environmental effects such as device switching effects when generating further transients. Thus, an accurate mathematical model is important because most system parameters vary with time. Curve modeling of power generation is a significant tool for evaluating system performance, monitoring and forecasting. Several numerical techniques compete to fit the curves of empirical data such as wind, solar, and demand power rates. This paper proposes a new modified methodology presented as a parametric technique to determine the system's modeling equations based on the Bode plot equations and the vector fitting (VF) algorithm by fitting the experimental data points. The modification is derived from the familiar VF algorithm as a robust numerical method. This development increases the application range of the VF algorithm for modeling not only in the frequency domain but also for all power curves. Four case studies are addressed and compared with several common methods. From the minimal RMSE, the results show clear improvements in data fitting over other methods. The most powerful features of this method is the ability to model irregular or randomly shaped data and to be applied to any algorithms that estimating models using frequency-domain data to provide state-space or transfer function for the model.


Subject(s)
Algorithms , Models, Theoretical , Renewable Energy/statistics & numerical data , Least-Squares Analysis , Mathematical Concepts , Solar Energy/statistics & numerical data , Wind
4.
PLoS One ; 12(9): e0185012, 2017.
Article in English | MEDLINE | ID: mdl-28934271

ABSTRACT

The main tool for measuring system efficiency in homes and offices is the energy monitoring of the household appliances' consumption. With the help of GUI through a PC or smart phone, there are various applications that can be developed for energy saving. This work describes the design and prototype implementation of a wireless PV-powered home energy management system under a DC-distribution environment, which allows remote monitoring of appliances' energy consumptions and power rate quality. The system can be managed by a central computer, which obtains the energy data based on XBee RF modules that access the sensor measurements of system components. The proposed integrated prototype framework is characterized by low power consumption due to the lack of components and consists of three layers: XBee-based circuit for processing and communication architecture, solar charge controller, and solar-battery-load matching layers. Six precise analogue channels for data monitoring are considered to cover the energy measurements. Voltage, current and temperature analogue signals were accessed directly from the remote XBee node to be sent in real time with a sampling frequency of 11-123 Hz to capture the possible surge power. The performance shows that the developed prototype proves the DC voltage matching concept and is able to provide accurate and precise results.


Subject(s)
Conservation of Energy Resources , Electric Power Supplies , Equipment Design , Radio Waves , Signal Processing, Computer-Assisted/instrumentation , Wireless Technology/instrumentation , Electronics , Humans
5.
Epidemiol Psychiatr Sci ; 26(4): 371-382, 2017 08.
Article in English | MEDLINE | ID: mdl-27018715

ABSTRACT

AIMS: The current study aimed to: (i) describe the extent of overall stigma as well as the differences in stigma towards people with alcohol abuse, dementia, depression, schizophrenia and obsessive compulsive disorder, as well as (ii) establish the dimensions of stigma and examine its correlates, in the general population of Singapore, using a vignette approach. METHODS: Data for the current study came from a larger nation-wide cross-sectional study of mental health literacy conducted in Singapore. The study population comprised Singapore Residents (Singapore Citizens and Permanent Residents) aged 18-65 years who were living in Singapore at the time of the survey. All respondents were administered the Personal and Perceived scales of the Depression Stigma scale and the Social Distance scale to measure personal stigma and social distance, respectively. Weighted mean and standard error of the mean were calculated for continuous variables, and frequencies and percentages for categorical variables. Exploratory structural equation modelling and confirmatory factor analysis were used to establish the dimensions of stigma. Multivariable linear regressions were conducted to examine factors associated with each of the stigma scale scores. RESULTS: The mean age of the respondents was 40.9 years and gender was equally represented (50.9% were males). The findings from the factor analysis revealed that personal stigma formed two distinct dimensions comprising 'weak-not-sick' and 'dangerous/unpredictable' while social distance stigma items loaded strongly into a single factor. Those of Malay and Indian ethnicity, lower education, lower income status and those who were administered the depression and alcohol abuse vignette were significantly associated with higher weak-not-sick scores. Those of Indian ethnicity, 6 years of education and below, lower income status and those who were administered the alcohol abuse vignette were significantly associated with higher dangerous/unpredictable scores. Those administered the alcohol abuse vignette were associated with higher social distance scores. CONCLUSION: This population-wide study found significant stigma towards people with mental illness and identified specific groups who have more stigmatising attitudes. The study also found that having a friend or family member with similar problems was associated with having lower personal as well as social distance stigma. There is a need for well-planned and culturally relevant anti-stigma campaigns in this population that take into consideration the findings of this study.


Subject(s)
Ethnicity/statistics & numerical data , Health Knowledge, Attitudes, Practice , Mental Disorders/psychology , Psychological Distance , Social Stigma , Stereotyping , Adolescent , Adult , Aged , Alcohol-Related Disorders/ethnology , Alcohol-Related Disorders/psychology , Cross-Sectional Studies , Culture , Dementia/ethnology , Dementia/psychology , Depression/ethnology , Depression/psychology , Ethnicity/psychology , Female , Humans , Male , Mental Disorders/ethnology , Middle Aged , Obsessive-Compulsive Disorder/ethnology , Obsessive-Compulsive Disorder/psychology , Psychiatric Status Rating Scales , Schizophrenia/ethnology , Singapore/epidemiology , Surveys and Questionnaires , Young Adult
6.
J Nutr Health Aging ; 20(10): 996-1001, 2016.
Article in English | MEDLINE | ID: mdl-27925139

ABSTRACT

OBJECTIVE: We examined the associations of handgrip strength, upper arm circumference, and waist circumference with dementia among Singapore older adults. DESIGN: Cross-sectional epidemiological study. SETTING: Residential homes, day care centres, nursing homes and institutions. PARTICIPANTS: 2,565 men and women aged 60 years and above who participated in the Well-being of the Singapore Elderly (WiSE) study in 2013. MEASUREMENTS: Socio-demographic correlates, dietary habits, health behaviours, grip strength, upper arm circumference, and waist circumference were collected. Grip strength was measured using a hand dynamometer with the dominant hand. Upper arm circumference was measured using a measuring tape around the thickest part of the upper arm while waist circumference measured in centimetres was measured at the narrowest part of the body between the chest and hips for women, and measured at the level of the umbilicus for men. Dementia was diagnosed using the 10/66 dementia diagnostic criteria. RESULTS: Mean grip strength was 13.07 kg (SE=0.60) for people with dementia and 21.98 kg (SE=0.26) for people without dementia. After adjusting for all factors, grip strength remained significantly associated with dementia (p <0.0001). Upper arm circumference was associated with dementia (p <0.0001) but this association was only significant in the univariate analysis. Waist circumference was not significantly associated with dementia. CONCLUSIONS: Lower grip strength was independently associated with dementia in the older adult population in Singapore. Further research needs to be done to ascertain whether this association exists for specific types of dementia and look into the relationship of other anthropometric measurements with dementia in Singapore.


Subject(s)
Arm , Dementia/epidemiology , Hand Strength , Waist Circumference , Aged , Aged, 80 and over , Body Mass Index , Cross-Sectional Studies , Female , Hand , Health Behavior , Homes for the Aged , Humans , Linear Models , Male , Middle Aged , Nursing Homes , Singapore , Socioeconomic Factors
7.
Comput Methods Programs Biomed ; 137: 149-166, 2016 Dec.
Article in English | MEDLINE | ID: mdl-28110721

ABSTRACT

Therapies with magnetic/electromagnetic field are employed to relieve pains or, to accelerate flow of blood-particles, particularly during the surgery. In this paper, a theoretical study of the blood flow along with particles suspension through capillary was made by the electro-magneto-hydrodynamic approach. Analytical solutions to the non-dimensional blood velocity and non-dimensional particles velocity are obtained by means of the Laplace transform with respect to the time variable and the finite Hankel transform with respect to the radial coordinate. The study of thermally transfer characteristics is based on the energy equation for two-phase thermal transport of blood and particles suspension with viscous dissipation, the volumetric heat generation due to Joule heating effect and electromagnetic couple effect. The solution of the nonlinear heat transfer problem is derived by using the velocity field and the integral transform method. The influence of dimensionless system parameters like the electrokinetic width, the Hartman number, Prandtl number, the coefficient of heat generation due to Joule heating and Eckert number on the velocity and temperature fields was studied using the Mathcad software. Results are presented by graphical illustrations.


Subject(s)
Blood Circulation , Capillaries/physiology , Electromagnetic Fields , Hydrodynamics , Models, Theoretical , Static Electricity
8.
Cir. mayor ambul ; 19(4): 132-135, oct.-dic. 2014. tab
Article in English | IBECS | ID: ibc-133064

ABSTRACT

Declaration: The authors would like to declare that this study has not been published or being reviewed by other journals. Retention of new information may be impaired during recovery from general anaesthesia. Patients are likely to be anxious if they cannot recall information conveyed at the surgeons’ postoperative visit. Previous studies have shown evidence of short-term memory impairment after GA. Patients undergoing day case knee arthroscopy under general anaesthesia were told five random words and three diagnostic findings from their operation, by the surgeon prior to discharge. The patients were telephoned the following day to test their recall of words and diagnostic findings, with a maximum possible score of eight. 96 patients were available for the telephone follow-up. The patients were grouped according to the interval between the end of anaesthesia and the time the information was given to them. For knee arthroscopy day cases it appears that, allowing as much time as possible after anaesthesia, at least two hours if possible, before reviewing a patient in the recovery area will likely enhance his/her later recall of the clinical information, potentially setting patient expectations at the appropriate level and improving compliance with postoperative rehabilitation. For the surgeons’ post-operative visit to be valuable to the patient, it should take place at least two hours following cessation of anaesthesia. It is advisable to endorse verbal communication with written information (AU)


No disponible


Subject(s)
Humans , Anesthesia, General , Arthroscopy/methods , Ambulatory Surgical Procedures/methods , Osteoarthritis, Knee/surgery , /methods , Continuity of Patient Care
9.
J Bone Joint Surg Br ; 94(8): 1090-6, 2012 Aug.
Article in English | MEDLINE | ID: mdl-22844051

ABSTRACT

Malunion is the most common complication of the distal radius with many modalities of treatment available for such a problem. The use of bone grafting after an osteotomy is still recommended by most authors. We hypothesised that bone grafting is not required; fixing the corrected construct with a volar locked plate helps maintain the alignment, while metaphyseal defect fills by itself. Prospectively, we performed the procedure on 30 malunited dorsally-angulated radii using fixed angle volar locked plates without bone grafting. At the final follow-up, 22 wrists were available. Radiological evidence of union, correction of the deformity, clinical and functional improvement was achieved in all cases. Without the use of bone grafting, corrective open wedge osteotomy fixed by a volar locked plate provides a high rate of union and satisfactory functional outcomes.


Subject(s)
Bone Plates , Fractures, Malunited/surgery , Radius Fractures/surgery , Adult , Bone Transplantation , Female , Fracture Healing , Fractures, Malunited/diagnostic imaging , Humans , Male , Middle Aged , Osteotomy/methods , Prospective Studies , Radiography , Radius Fractures/diagnostic imaging , Range of Motion, Articular , Recovery of Function/physiology , Treatment Outcome , Wrist Joint/diagnostic imaging , Wrist Joint/physiopathology , Young Adult
10.
Environ Technol ; 31(12): 1349-70, 2010 Nov.
Article in English | MEDLINE | ID: mdl-21121459

ABSTRACT

Enantioselective analysis of some pharmaceuticals during wastewater treatment has the potential to reveal significant insights regarding the effectiveness of biotransformation processes. Furthermore, enantioselective analysis of chiral pharmaceuticals in the aquatic environment may provide a useful historical record revealing the dominant source of (treated or untreated) wastewater contamination. This review of the recent scientific literature has identified only a handful of studies that have directly investigated these promising applications. However, a range of enantioselective analytical techniques are likely to be adaptable from those which have been developed within the pharmaceutical industry. These include direct enantioseparations of enantiomers on chiral stationary phases as well as indirect separations by achiral stationary phases after chiral derivatization to form pairs of physically distinguishable diastereomers. Further investigations of the patterns of enantiomeric fractionation of pharmaceuticals in wastewater and environmental samples will provide an increasingly solid understanding of the relationship between biotransformation processes and the often overlooked parameter of enantiomeric fraction.


Subject(s)
Environmental Restoration and Remediation/methods , Pharmaceutical Preparations/chemistry , Waste Disposal, Fluid/methods , Water Pollutants, Chemical/chemistry , Water Purification/methods , Biotransformation , Models, Molecular , Pharmaceutical Preparations/analysis , Stereoisomerism , Water Pollutants, Chemical/analysis
11.
Ann Thorac Surg ; 89(6): 1918-24, 2010 Jun.
Article in English | MEDLINE | ID: mdl-20494049

ABSTRACT

BACKGROUND: Bicuspid aortic valve is associated with aortic aneurysm formation that may extend beyond the ascending aorta. METHODS: Between 1979 and 1997, 143 bicuspid aortic valve patients had aortic valve operations with replacement of an aneurysmal ascending aorta: 93 (65%) underwent full root replacement and 50 (35%) underwent separate valve and graft replacement. Distal aortic anastomosis was open in 42 patients (29%) and closed in 101 (71%). Late survival and complications were compared by surgical technique. RESULTS: Patients undergoing full root replacement tended to be younger (mean age 46 +/- 16 vs 59 +/- 13, p < 0.001) and presented with more aortic insufficiency (80% vs 35%, p < 0.001). Three (2.1%) hospital deaths occurred. Event-free survival was 82% (95% confidence interval, 75% to 88%) at 10 years and 41% (95% confidence interval, 11% to 71%) at 20 years. At a median follow-up of 11.5 years, the incidence of new aneurysms and late aortic complications were not significantly different among the procedure groups. Age at the time of operation was the only predictor of late survival (hazard ratio, 1.07; p = 0.007). CONCLUSIONS: Aortic root replacement with distal aortic reconstruction can be achieved with very low operative mortality and excellent long-term outcomes in patients with bicuspid aortic valve and dilated ascending aorta. The type of surgical procedure done in the aortic root and in the distal ascending aorta does not influence late survival, subsequent operation, or aortic complications. This is likely influenced by our patient-specific strategy when replacing the aortic root and distal ascending aorta.


Subject(s)
Aortic Aneurysm/complications , Aortic Aneurysm/surgery , Aortic Valve/abnormalities , Aortic Valve/surgery , Cardiac Surgical Procedures/adverse effects , Cardiac Surgical Procedures/methods , Female , Humans , Male , Middle Aged , Postoperative Complications/epidemiology , Retrospective Studies , Treatment Outcome
12.
J Clin Microbiol ; 47(7): 2226-31, 2009 Jul.
Article in English | MEDLINE | ID: mdl-19439543

ABSTRACT

Brucella species are highly monomorphic, with minimal genetic variation among species, hindering the development of reliable subtyping tools for epidemiologic and phylogenetic analyses. Our objective was to compare two distinct multiple-locus variable-number tandem-repeat analysis (MLVA) subtyping methods on a collection of 101 Brucella melitensis isolates from sporadic human cases of brucellosis in Egypt (n = 83), Qatar (n = 17), and Libya (n = 1). A gel-based MLVA technique, MLVA-15(IGM), was compared to an automated capillary electrophoresis-based method, MLVA-15(NAU), with each MLVA scheme examining a unique set of variable-number tandem repeats. Both the MLVA(IGM) and MLVA(NAU) methods were highly discriminatory, resolving 99 and 101 distinct genotypes, respectively, and were able to largely separate genotypes from Egypt and Qatar. The MLVA-15(NAU) scheme presented higher strain-to-strain diversity in our test population than that observed with the MLVA-15(IGM) assay. Both schemes were able to genetically correlate some strains originating from the same hospital or region within a country. In addition to comparing the genotyping abilities of these two schemes, we also compared the usability, limitations, and advantages of the two MLVA systems and their applications in the epidemiological genotyping of human B. melitensis strains.


Subject(s)
Bacterial Typing Techniques/methods , Brucella melitensis/classification , Brucella melitensis/genetics , Brucellosis/microbiology , DNA Fingerprinting/methods , Minisatellite Repeats , Brucella melitensis/isolation & purification , Cluster Analysis , Humans , Middle East , Molecular Epidemiology/methods , Sensitivity and Specificity
13.
Am J Physiol Heart Circ Physiol ; 296(1): H43-50, 2009 Jan.
Article in English | MEDLINE | ID: mdl-19011044

ABSTRACT

The mechanisms for the beneficial impact of bone marrow cell (BMC) therapy after myocardial infarction (MI) are ill defined. We hypothesized that the implanted cells improve function by attenuating post-MI inflammation and repair. In mice, 3 x 10(5) fresh BMCs were implanted immediately after coronary ligation. Cardiac function was evaluated over time. Inflammatory cytokines and cells were measured, and their impacts on the (myo)fibroblastic repair response, angiogenesis, and scar formation were determined. All differences below had P values of <0.05. BMC implantation reduced the decline in fractional shortening and ventricular dilation. Invasive hemodynamics confirmed a difference in systolic function at day 7 and diastolic function at day 28 favoring the BMC group. Interestingly, BMC implantation caused a 1.6-fold increase in the number of macrophages infiltrating the infarct but did not affect neutrophils. This increase was associated with a 1.9-fold higher myocardial TNF-alpha level. The heightened inflammatory response was associated with a 1.4-fold induction of transforming growth factor-beta and a 1.3-fold induction of basic fibroblast growth factor. These changes resulted in a 1.6-fold increase in alpha-smooth muscle actin and a 1.9-fold increase in total discoidin domain receptor 2-expressing cells in the BMC group. These two markers are expressed by cardiac (myo)fibroblasts. Capillary density in the border zone increased 2.0-fold. Consistent with a more robust repair-mediated scar "contracture," the final scar size was 0.7-fold smaller in the BMC group. In conclusion, after MI, BMC therapy induced a more robust inflammatory response that improved the "priming" of the (myo)fibroblast repair phase. Enhancing this response may further improve the beneficial impact of cellular therapy.


Subject(s)
Bone Marrow Transplantation/adverse effects , Heart/physiology , Myocarditis/etiology , Animals , Blood Pressure/physiology , Blood Volume/physiology , Cell Proliferation , Coronary Vessels/physiology , Cytokines/metabolism , Female , Fibroblasts/physiology , Flow Cytometry , Heart Function Tests , Immunohistochemistry , Mice , Mice, Inbred C57BL , Myocardium/metabolism
15.
J Thorac Cardiovasc Surg ; 135(4): 901-7, 907.e1-2, 2008 Apr.
Article in English | MEDLINE | ID: mdl-18374778

ABSTRACT

OBJECTIVES: Bicuspid aortic valves are associated with a poorly characterized connective tissue disorder that predisposes to aortic catastrophes. Because no criterion exists dictating the appropriate extent of aortic resection in aneurysmal disease of the bicuspid aortic valve, we studied the patterns of aortic dilation in this population. METHODS: Sixty-four patients with bicuspid aortic valves who underwent computed tomographic or magnetic resonance angiography and echocardiography were retrospectively identified between January 2002 and March 2006. Orthonormal 2-dimensional or 3-dimensional aortic diameters were measured at 10 levels. Agglomerative hierarchic clustering with centered correlation distance measurements and complete linkage analysis was used to detect distinct patterns of aortic dilatation. RESULTS: Mean aortic diameter was 28.1 +/- 0.7 mm at the annulus and 21.7 +/- 0.4 mm at the diaphragmatic hiatus. The aorta was largest in the tubular ascending aorta (45.9 +/- 1.0 mm). Compared with the descending aorta, the transverse aortic arch was also dilated (P < .01). Cluster analysis showed 4 patterns of aortic dilatation: cluster I, aortic root alone (n = 8, 13%); cluster II, tubular ascending aorta alone (n = 9, 14%); cluster III, tubular portion and transverse arch (n = 18, 28%); and, cluster IV, aortic root and tubular portion with tapering across the transverse arch (n = 29, 45%). CONCLUSION: Distinct patterns of aortic dilatation in patients with bicuspid aortic valves call for an individualized degree of aortic replacement to minimize late aortic complications and reoperation. Patients in clusters III and IV should have transverse arch replacement (plus concomitant root replacement in cluster IV). Patients in cluster I should undergo complete aortic root replacement, whereas in patients in cluster II supracommissural ascending aortic grafting is adequate.


Subject(s)
Aortic Aneurysm/physiopathology , Aortic Valve/pathology , Heart Valve Diseases/physiopathology , Adolescent , Adult , Aged , Aortic Aneurysm/complications , Aortic Aneurysm/diagnosis , Female , Heart Valve Diseases/complications , Heart Valve Diseases/diagnosis , Humans , Male , Middle Aged , Retrospective Studies
16.
FASEB J ; 22(3): 930-40, 2008 Mar.
Article in English | MEDLINE | ID: mdl-17967925

ABSTRACT

Cardiovascular disease is the number-one cause of mortality in the developed world. The aim of this study is to define the mechanisms by which bone marrow progenitor cells are mobilized in response to cardiac ischemic injury. We used a closed-chest model of murine cardiac infarction/reperfusion, which segregated the surgical thoracotomy from the induction of cardiac infarction, so that we could study isolated fluctuations in cytokines without the confounding impact of surgery. We show here that bone marrow activation of the c-kit tyrosine kinase receptor in response to released soluble KitL is necessary for bone marrow progenitor cell mobilization after ischemic cardiac injury. We also show that release of KitL and c-kit activation require the activity of matrix metalloproteinase-9 within the bone marrow compartment. Finally, we demonstrate that mice with c-kit dysfunction develop cardiac failure after myocardial infarction and that bone marrow transplantation rescues the failing cardiac phenotype. In light of the ongoing trials of progenitor cell therapy for heart disease, our study outlines the endogenous repair mechanisms that are invoked after cardiac injury. Amplification of this pathway may aid in restoration of cardiac function after myocardial infarction.


Subject(s)
Bone Marrow/enzymology , Myocardial Infarction/enzymology , Proto-Oncogene Proteins c-kit/metabolism , Stem Cells/physiology , Animals , Cell Movement , Cells, Cultured , Disease Models, Animal , Endothelial Cells/cytology , Enzyme Activation , Female , Humans , Matrix Metalloproteinase 9/metabolism , Mice , Mice, Inbred C57BL , Myocardial Infarction/blood , Proto-Oncogene Proteins c-kit/genetics , RNA, Messenger/biosynthesis , Stem Cell Factor/blood , Stem Cell Factor/metabolism , Stem Cells/cytology , Up-Regulation
17.
Curr Opin Cardiol ; 22(6): 497-503, 2007 Nov.
Article in English | MEDLINE | ID: mdl-17921735

ABSTRACT

PURPOSE OF REVIEW: Techniques of aortic root replacement have been developed that preserve the native aortic valve. These techniques avoid anticoagulation in patients who would otherwise receive a composite valve graft with a mechanical valve. RECENT FINDINGS: Longer-term data on the longevity of the main two techniques of aortic valve-sparing operations, the root remodeling and the valve reimplantation technique, are now becoming available. Root remodeling appears to have acceptable outcomes in patients without annuloaortic ectasia or Marfan syndrome. In such patients, the aortic valve reimplantation technique provides superior longevity because it provides external support for the aortic annulus and prevents ongoing dilatation. SUMMARY: Although aortic valve-sparing operations are being performed more frequently, particularly in younger patient populations, these procedures have not been adopted in the current guidelines. The excellent long-term outcomes of such procedures should facilitate their widespread adoption.


Subject(s)
Aorta/surgery , Aortic Aneurysm/surgery , Aortic Valve/surgery , Vascular Surgical Procedures/methods , Humans
18.
J Clin Apher ; 22(1): 5-9, 2007 Feb.
Article in English | MEDLINE | ID: mdl-17266120

ABSTRACT

The aim of this study was to analyze the impact of various donor and machine parameters on PLT yield in 127 PLT apheresis procedures, to optimize PLT yield achieving clinical and economic advantages. One hundred and twenty-seven apheresis procedures were analyzed. Age, gender, volume processed, Hb, and PLT precounts were included as donor predicting variables. AC infusion rate, processing time, and plasma volume collected with PLTs were assessed as machine parameters. We evaluated the post-transfusion effectiveness in 23 patients with thrombocytopenia, studying the effect of PLT dose, ABO group, and PLT storage time. Females gave higher yields, compared to males, P<0.01. PLT yield correlated positively with PLT precount (r=0.512), and TBV (r=0.404), and negatively with donor preapheresis Hb (r=-0.306). Processing time and AC infusion rate had a positive impact on PLT yield. Post-apheresis decrease in PLT count was 53.6+/-26.3x10(11). Donors with Hb>or=12 g/dl, donated safely. Most of the complications were citrate related (13.4% of all procedures). PLT increments in transfused patients correlated positively with the number of units transfused (r=0.41), and negatively with PLT storage days (r=-0.342). PLT increments in patients receiving ABO-compatible PLTs were 75% higher, compared to the increments in patients receiving incompatible PLTs. PLT count and volume processed were the main predictors of PLT yield. Increasing the processing time, the AC infusion rate, or the volume of plasma obtained with PLTs can increase PLT yields. High PLT dose, short storage time, as well as ABO compatibility should be considered during PLT transfusion.


Subject(s)
Platelet Transfusion/standards , Plateletpheresis/standards , Tissue Donors , ABO Blood-Group System , Age Factors , Blood Group Incompatibility , Female , Hemoglobins , Humans , Male , Platelet Count , Plateletpheresis/instrumentation , Retrospective Studies , Sex Factors , Thrombocytopenia/therapy
20.
Mycoses ; 49(6): 504-9, 2006 Nov.
Article in English | MEDLINE | ID: mdl-17022769

ABSTRACT

Exophiala (Wangiella) dermatitidis is a melanised (darkly pigmented) yeast-like organism that has been reported from the environment and wild animals. The organism is a frequent coloniser of lungs of patients with cystic fibrosis and causes occasional disseminated phaeohyphomycosis and fungaemia. Exophiala dermatitidis is distributed worldwide, but cerebral cases are restricted to East Asia. We report a case of 54-year-old Qatari female patient with a known history of cancer, suffering from pulmonary disorder. Culture of endotracheal aspirate revealed the growth of E. dermatitidis concomitant with Candida krusei. The final diagnosis of E. dermatitidis and attribution to genotype B was achieved by sequencing the rDNA internal transcribed spacer (ITS) region. The present case concerns a pulmonary colonisation by E. dermatitidis, similar to that commonly seen in cystic fibrosis patients. For the detection of E. dermatitidis in clinical specimens culturing techniques are required. The patient finally expired with persistent cancer and C. krusei fungaemia. Review of literature and listing of E. dermatitidis cases published after 1992 show a sharp increase in clinical cases during the 1990s.


Subject(s)
Bronchoalveolar Lavage Fluid/microbiology , Exophiala/isolation & purification , Lung Diseases, Fungal/microbiology , Uterine Cervical Neoplasms/complications , Colonic Neoplasms/secondary , Fatal Outcome , Female , Humans , Intubation, Intratracheal , Middle Aged , Urinary Bladder Neoplasms/secondary , Uterine Cervical Neoplasms/pathology
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