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1.
J Prev Alzheimers Dis ; 10(3): 571-580, 2023.
Article in English | MEDLINE | ID: mdl-37357299

ABSTRACT

BACKGROUND: Large-scale preclinical Alzheimer's disease study based on ß-amyloid positron emission tomography (PET) has not been conducted in China. OBJECTIVES: Establish a cohort on Alzheimer's disease spectrum, especially the preclinical stages, and determine the factors influencing the acceptance of ß-amyloid PET scan screening in China. DESIGN: Longitudinal. SETTING: Shanghai, China. PARTICIPANTS: A total of 4386 participants were screened and 2451 participants who met enrollment criteria were eventually included in this report. MEASUREMENTS: The multidimensional data was collected, including comprehensive assessments, PET and magnetic resonance imaging scans, genetics, and plasma biomarkers. RESULTS: There were 571 participants in the normal cognition group, 625 participants in the subjective cognitive decline group, 155 participants in the objectively defined subtle cognitive decline group, 501 participants in the mild cognitive impairment group, 471 participants in Alzheimer's disease group, and 128 participants with cognitive impairment from other known causes. Significant differences in demographics, florbetapir PET, APOE, and neuropsychological tests were found among the groups. Eight hundred and seventeen participants (33.3%) completed the florbetapir PET scanning. Non-demented individuals with higher age, lower education years, male, with a family history of dementia, and higher self-report depression prefer to undergo PET scans. Acceptance of PET scans did not correlate with objectively assessed cognitive impairment. CONCLUSIONS: The Chinese Preclinical Alzheimer's Disease Study was designed to establish a large-scale cohort with comprehensive data collection. Our findings may help to understand the factors affecting the acceptance of ß-amyloid PET in urban areas of China and help us address the low acceptance challenge.


Subject(s)
Alzheimer Disease , Amyloid beta-Peptides , Positron-Emission Tomography , Humans , Male , Alzheimer Disease/diagnosis , Alzheimer Disease/diagnostic imaging , Apolipoproteins E , China , East Asian People , Positron-Emission Tomography/methods
2.
East Asian Arch Psychiatry ; 31(4): 97-104, 2021 Dec.
Article in English | MEDLINE | ID: mdl-34987120

ABSTRACT

OBJECTIVES: To determine the psychometric properties of the Chinese version of the work and social adjustment scale (CWSAS) in outpatients with common mental disorders, and to evaluate the correlations of CWSAS with Physical Health Questionnaire-9 (PHQ-9), General Anxiety Disorder-7 (GAD-7), World Health Organization Five Well-being Index (WHO-5), and Chinese version of the Perceived Stress Scale-10 (CPSS-10). METHODS: Forward and backward translations of the CWSAS was performed. Between October 2018 and March 2020, 252 outpatients with a common mental disorder who had a job or a job plan were recruited from two psychiatric centres in Hong Kong. Participants were asked to complete the CWSAS, PHQ-9, GAD-7, WHO-5, and CPSS-10. Classical test theory and Rasch analysis were undertaken to determine the psychometric properties of the CWSAS and its correlations with other tools. RESULTS: Principal component analysis revealed that the CWSAS was a one-factor structure and showed adequate convergent and discriminant validities, internal consistency, item-total correlation, and inter-item correlation. There was a significant group difference in terms of employment status. CPSS-10 and PHQ-9 were predictors for CWSAS score. The CWSAS was a distinct factor among other outcome measures. Rasch analysis indicated that the CWSAS was well-targeted and unidimensional. The CWSAS had an adequate person separation index, item separation index, person reliability, and item reliability. No categorical disordering was found, whereas inadequate adjacent threshold distance was reported. The item of ability to work indicated a noticeable differential item functioning in employment status and main source of finance. CONCLUSION: The CWSAS is psychometrically appropriate to measure functional outcomes in outpatients with common mental disorders.


Subject(s)
Mental Disorders , Outpatients , Hong Kong , Humans , Psychometrics , Reproducibility of Results , Social Adjustment , Surveys and Questionnaires
3.
Clin Genet ; 88(5): 450-5, 2015 Nov.
Article in English | MEDLINE | ID: mdl-25318593

ABSTRACT

Type of cancer and age of onset in individuals with inherited aberrations in the tumour suppressor gene TP53 are variable, possibly influenced by genetic modifiers and different environmental exposure. Since 2009, the modified Chompret criteria (MCC) have been used to identify individuals for TP53 mutation screening. Using the TP53 mutation database maintained by the International Agency for Research on Cancer (IARC), we investigated if the MCC, mainly developed for a Caucasian population, was also applicable in Asia. We identified several differences in Asian families compared with similar Caucasian cohorts, suggesting that identification and management of Li-Fraumeni syndrome in Asia do not completely mirror that of North America and Western Europe. Early gastric cancer (<40 years) may be considered a new addition to the MCC especially for Asian families.


Subject(s)
Li-Fraumeni Syndrome/complications , Mutation , Stomach Neoplasms/epidemiology , Tumor Suppressor Protein p53/genetics , Asian People/genetics , Humans , Stomach Neoplasms/genetics
4.
Oncogene ; 30(13): 1518-30, 2011 Mar 31.
Article in English | MEDLINE | ID: mdl-21119603

ABSTRACT

The fibroblast growth factor 8b (FGF8b) oncogene is known to be primarily involved in the tumorigenesis and progression of hormone-related cancers. Its role in other epithelial cancers has not been investigated, except for esophageal cancer, in which FGF8b overexpression was mainly found in tumor biopsies of male patients. These observations were consistent with previous findings in these cancer types that the male sex-hormone androgen is responsible for FGF8b expression. Nasopharyngeal carcinoma (NPC) is a highly metastatic cancer of head and neck commonly found in Asia. It is etiologically associated with Epstein-Barr Virus (EBV) infection, inflammatory tumor microenvironment and relatively higher male predominance. Here, we reported for the first time that FGF8b is overexpressed in this EBV-associated non-hormone-related cancer of the head and neck, NPC. More importantly, overexpression of FGF8b mRNA and protein was detected in a large majority of NPC tumors from both male and female genders, in addition to multiple NPC cell lines. We hypothesized that FGF8b overexpression may contribute to NPC tumorigenesis. Using EBV-associated NPC cell lines, we demonstrated that specific knockdown of FGF8b by small interfering RNA inhibited cell proliferation, migration and invasion, whereas exogenous FGF8b stimulated these multiple phenotypes. Further mechanistic investigation revealed that in addition to NF-κB signaling (a major inflammatory signaling pathway known to be activated in NPC), an important EBV oncoprotein, the latent membrane protein 1 (LMP1), was found to be a direct inducer of FGF8b overexpression in NPC cells, whereas androgen (testosterone) has minimal effect on FGF8b expression in EBV-associated NPC cells. In summary, our study has identified LMP1 as the first viral oncogene capable of directly inducing FGF8b (an important cellular oncogene) expression in human cancer cells. This novel mechanism of viral-mediated FGF8 upregulation may implicate a new role of oncoviruses in human carcinogenesis.


Subject(s)
Fibroblast Growth Factor 8/physiology , Gene Expression Regulation, Neoplastic , Herpesvirus 4, Human/pathogenicity , Oncogenes , Carcinoma , Cell Movement , Cell Proliferation , Female , Fibroblast Growth Factor 8/antagonists & inhibitors , Fibroblast Growth Factor 8/genetics , Humans , Male , Mitogen-Activated Protein Kinases/metabolism , NF-kappa B/physiology , Nasopharyngeal Carcinoma , Nasopharyngeal Neoplasms/pathology , Nasopharyngeal Neoplasms/virology , Neoplasm Invasiveness , RNA, Messenger/analysis , RNA, Small Interfering/genetics , Viral Matrix Proteins/physiology
5.
Neuroscience ; 168(1): 179-89, 2010 Jun 16.
Article in English | MEDLINE | ID: mdl-20303392

ABSTRACT

As one major line of research on brain plasticity, many imaging studies have been conducted to identify the functional and structural reorganization associated with musical expertise. Based on previous behavioral research, the present study used functional magnetic resonance imaging to identify the neural correlates of superior verbal memory performance in musicians. Participants with and without musical training performed a verbal memory task to first encode a list of words auditorily delivered and then silently recall as many words as possible. They performed in separate blocks a control task involving pure tone pitch judgment. Post-scan recognition test showed better memory performance in musicians than non-musicians. During memory retrieval, the musicians showed significantly greater activations in bilateral though left-lateralized visual cortex relative to the pitch judgment baseline. In comparison, no such visual cortical activations were found in the non-musicians. No group differences were observed during the encoding stage. The results echo a previous report of visual cortical activation during verbal memory retrieval in the absence of any visual sensory stimulation in the blind population, who are also known to possess superior verbal memory. It is suggested that the visual cortex can be recruited to serve as extra memory resources and contributes to the superior verbal memory in special situations. While in the blind population, such cross-modal functional reorganization may be induced by sensory deprivation; in the musicians it may be induced by the long-term and demanding nature of musical training to use as much available neural resources as possible.


Subject(s)
Memory , Music , Verbal Behavior , Visual Cortex/physiology , Acoustic Stimulation , Auditory Cortex/physiology , Brain Mapping , Female , Humans , Magnetic Resonance Imaging , Pitch Discrimination , Psychomotor Performance , Young Adult
6.
Eur Respir J ; 35(4): 836-42, 2010 Apr.
Article in English | MEDLINE | ID: mdl-19797130

ABSTRACT

This study aimed to explore the effect of mandibular advancement splints (MAS) on upper airway anatomy during wakefulness in obstructive sleep apnoea (OSA). Patients commencing treatment for OSA with MAS were recruited. Response to treatment was defined by a >or=50% reduction in the apnoea/hypopnoea index. Nasopharyngoscopy was performed in the supine position. Nasopharyngoscopy was performed in 18 responders and 17 nonresponders. Mandibular advancement caused an increase in the calibre of the velopharynx (mean+/- sem +40+/-10%), with relatively minor changes occurring in the oropharynx and hypopharynx. An increase in cross-sectional area of the velopharynx with mandibular advancement occurred to a greater extent in responders than nonresponders (+56+/-16% versus +22+/-13%; p<0.05). Upper airway collapse during the Müller manoeuvre, relative to the baseline cross-sectional area, was greater in nonresponders than responders in the velopharynx (-94+/-4% versus -69+/-9%; p<0.01) and oropharynx (-37+/-6% versus -16+/-3%; p<0.01). When the Müller manoeuvre was performed with mandibular advancement, airway collapse was greater in nonresponders than responders in the velopharynx (-80+/-11% versus +9+/-37%; p<0.001), oropharynx (-36+/-6% versus -20+/-5%; p<0.05) and hypopharynx (-64+/-6% versus -42+/-6%; p<0.05). These results indicate that velopharyngeal calibre is modified by MAS treatment and this may be useful for predicting treatment response.


Subject(s)
Mandibular Advancement/instrumentation , Pharyngostomy , Sleep Apnea, Obstructive , Adult , Aged , Female , Humans , Hypopharynx/pathology , Hypopharynx/physiopathology , Logistic Models , Male , Middle Aged , Observer Variation , Oropharynx/pathology , Oropharynx/physiopathology , Pharyngostomy/statistics & numerical data , Polysomnography , Predictive Value of Tests , Sleep Apnea, Obstructive/pathology , Sleep Apnea, Obstructive/physiopathology , Sleep Apnea, Obstructive/therapy , Supine Position , Wakefulness
7.
Intern Med J ; 40(2): 102-6, 2010 Feb.
Article in English | MEDLINE | ID: mdl-19811552

ABSTRACT

Obstructive sleep apnoea (OSA) is a common disorder characterized by the repetitive complete or partial collapse of the upper airway during sleep. It results in intermittent hypoxaemia and hypercapnia, cortical arousals and surges of sympathetic activity. The occurrence of OSA has also been linked to serious long-term adverse health consequences; such as hypertension, metabolic dysfunction, cardiovascular disease, neurocognitive deficits and motor vehicle accidents. There have been several advances in the field of particular clinical importance: (i) the development of portable monitoring as part of a simplified clinical algorithm for the diagnosis of OSA in selected patients; (ii) growing awareness of the cardio-metabolic health consequences of OSA and (iii) emerging evidence to support a range of non-continuous positive airway pressure (CPAP) treatment modalities, such as oral appliances.


Subject(s)
Sleep Apnea, Obstructive/diagnosis , Sleep Apnea, Obstructive/therapy , Continuous Positive Airway Pressure/methods , Humans , Hypercapnia/diagnosis , Hypercapnia/etiology , Hypercapnia/therapy , Sleep Apnea, Obstructive/complications
8.
J Neurol Neurosurg Psychiatry ; 80(10): 1099-106, 2009 Oct.
Article in English | MEDLINE | ID: mdl-19389718

ABSTRACT

OBJECTIVE: The present study aimed to examine and compare memory processing in patients with unilateral temporal lobe epilepsy (TLE) before and after surgery using functional magnetic resonance imaging (fMRI). METHODS: Seventeen preoperative patients with unilateral TLE (nine left, eight right) and eight healthy controls were recruited. They performed a complex visual scene-encoding task during fMRI to measure memory activation in the mesial temporal lobe. Their memory performance was evaluated using standardised neuropsychological tests. After unilateral temporal lobe resection (either temporal lobectomy, selective amygdalohippocampectomy or lesionectomy), the same fMRI paradigm and neuropsychological tests were administered to the patient group. RESULTS: Left-TLE patients demonstrated a decline in verbal memory after left temporal lobe resection. Their postoperative verbal and visual memory performance was positively associated with postoperative functional activation in the right mesial temporal lobe, whereas the postoperative memory performance of right-TLE patients was positively associated with postoperative functional activation in the left mesial temporal lobe, contralateral to their respective side of resection. CONCLUSION: Postoperative memory performance was significantly associated with functional activation contralateral to the side of resection in patients with unilateral TLE, and the function of the contralateral mesial temporal lobe might play an important role in supporting memory performance after temporal lobe resection.


Subject(s)
Epilepsy, Temporal Lobe/pathology , Epilepsy, Temporal Lobe/psychology , Magnetic Resonance Imaging , Memory/physiology , Adolescent , Adult , Anterior Temporal Lobectomy , Epilepsy, Temporal Lobe/surgery , Female , Follow-Up Studies , Humans , Male , Neuropsychological Tests , Prospective Studies , Temporal Lobe/physiopathology , Treatment Outcome , Young Adult
9.
Scand J Rheumatol ; 35(5): 356-8, 2006.
Article in English | MEDLINE | ID: mdl-17062434

ABSTRACT

OBJECTIVES: To investigate the anti-inflammatory and anti-oxidative effects of anthocyanins from cherries on Freund's adjuvant-induced arthritis (AIA) in rats. METHODS: Arthritis was induced intradermally by injection with 0.1 mL of complete Freund's adjuvant (CFA) into the right hind footpad of male Sprague Dawley (SD) rats. Anthocyanins at 40, 20 and 10 mg/kg (body weight) were administered orally to the treated rats for 28 days after the injection. Tumour necrosis factor-alpha (TNFalpha) in serum and prostaglandin E2 (PGE2) in paws were assayed by radioimmunoassay (RIA), and anti-oxidative effects was assayed by measuring total anti-oxidative capacity (T-AOC), superoxide dismutase (SOD) and malondialdehyde (MDA) in serum. RESULTS: Anthocyanins at 40 mg/kg significantly decreased the levels of TNFalpha in serum and PGE2 in paws, simultaneously improving the anti-oxidative status of AIA. We found that at this dosage T-AOC was potentized, the activity of SOD increased and the level of MDA in serum decreased. However, anthocyanins at 20 and 10 mg/kg had less effect on the inflammatory factors and anti-oxidative capacity of AIA. CONCLUSIONS: Anthocyanins have potential anti-inflammatory and anti-oxidative effects on AIA.


Subject(s)
Anthocyanins/pharmacology , Anti-Inflammatory Agents/pharmacology , Antioxidants/pharmacology , Arthritis, Experimental/drug therapy , Prunus , Animals , Anthocyanins/administration & dosage , Anti-Inflammatory Agents/administration & dosage , Antioxidants/administration & dosage , Arthritis, Experimental/blood , Arthritis, Experimental/chemically induced , Dinoprostone/metabolism , Freund's Adjuvant , Male , Malondialdehyde/blood , Prunus/chemistry , Rats , Rats, Sprague-Dawley , Superoxide Dismutase/blood , Tumor Necrosis Factor-alpha/blood
10.
Cell Biol Toxicol ; 22(4): 293-302, 2006 Jul.
Article in English | MEDLINE | ID: mdl-16835731

ABSTRACT

Protocatechuic acid (PCA), chlorogenic acid (CA) and luteolin (LT) are plant phenols found in Chinese medicinal herbs such as Lonicera japonica. Cytotoxicity assays showed that PCA, CA and LT (at 100 micromol/L) effectively killed the HepG2 hepatocellular carcinoma cells. Among these three naturally occurring compounds, only PCA was capable of stimulating the c-Jun N-terminal kinase (JNK) and p38 subgroups of the mitogen-activated protein kinase (MAPK) family. Coincidently, PCA-induced cell death was rescued by specific inhibitors for JNK and p38, while the cytotoxicities of CA and LT were partially eliminated by the antioxidant effect of N-acetyl-L-cysteine (NAC). Further investigation demonstrated that the aqueous extract of Lonicera japonica also triggered HepG2 cell death in a JNK-dependent manner, but the amount of PCA alone in this herbal extract was insufficient to contribute the subsequent cytotoxic effect. Collectively, our results suggest that PCA is a naturally occurring compound capable of inducing JNK-dependent hepatocellular carcinoma cell death.


Subject(s)
Antineoplastic Agents/pharmacology , Carcinoma, Hepatocellular/drug therapy , Hydroxybenzoates/pharmacology , JNK Mitogen-Activated Protein Kinases/metabolism , Liver Neoplasms/drug therapy , Cell Death , Cell Line, Tumor , Dose-Response Relationship, Drug , Humans , Lonicera/metabolism , MAP Kinase Signaling System , Models, Chemical , Phosphorylation , Plant Extracts/pharmacology , p38 Mitogen-Activated Protein Kinases/metabolism
11.
Drug Dev Ind Pharm ; 32(4): 413-22, 2006 Apr.
Article in English | MEDLINE | ID: mdl-16638679

ABSTRACT

Puerarin is a potential therapeutic agent for cardiovascular diseases. But its poor oral bioavailability restricts its clinical application. In present study, as an evaluation of a formulation to improve the bioavailability of the drug, puerarin and its phospholipid complex were given to rats by intragastrically (i.g.) administration to compare pharmacokinetic, tissue distribution, and excretion. Serum samples were obtained at designated times after a single oral dose of 400 mg/kg puerarin or its complex. Tissue samples (heart, liver, spleen, kidney, lung, and brain), urine, and feces were collected and analyzed by a sensitive and specific high performance liquid chromatography (HPLC) method after i.g. administration of puerarin or its phospholipid complex. Compartmental and non-compartmental analyses were applied to the serum concentration versus time data. Pharmacokinetic parameters were calculated using the 3P97 pharmacokinetic software package. An open two-compartment, first-order model was selected for pharmacokinetic modeling. The results showed that after i.g. administration of 400 mg/kg puerarin and its phospholipid complex (equivalent to 400 mg/kg of puerarin), the pharmacokinetic parameters of the two formulations were different. The serum concentrations reached peaks at 0.894+/-0.521 h and 0.435+/-0.261 h, respectively, indicating the complex was more readily absorbed in serum than puerarin. The maximum concentrations for puerarin and its complex were 1.367+/-0.586 mg.L(-1) and 2.202+/-1.28 mg.L(-1) and AUC were 5.779+/-1.662 mg.h. L(-1) and 8.456+/-0.44 mg.h L(-1), respectively, indicating a higher bioavailability for the complex. The widely distribution characteristics of puerarin and its complex in tissues post-i.g. administration was identical and in a descending order as follows: lung, kidney, liver, heart, spleen, and brain. However, the amount was different. Puerarin distribution was higher in heart, lung, and brain after administering the complex. The cumulative 72 h urinary excretion of puerarin after i.g. administration of puerarin and its complex accounted for 1.05%, 1.11% of the administered dose, respectively. The cumulative feces excretion of puerarin was 32.3% and 25.5%. To sum up, oral administration of puerarin phospholipid complex modified the pharmacokinetics and tissue distribution of puerarin and it could be an effective oral formulation for puerarin.


Subject(s)
Isoflavones/pharmacokinetics , Phospholipids/pharmacokinetics , Vasodilator Agents/pharmacokinetics , Administration, Oral , Animals , Chromatography, High Pressure Liquid , Feces/chemistry , Isoflavones/blood , Isoflavones/urine , Molecular Structure , Phospholipids/blood , Phospholipids/urine , Rats , Rats, Sprague-Dawley , Tissue Distribution , Vasodilator Agents/blood , Vasodilator Agents/urine
12.
AMIA Annu Symp Proc ; : 494-8, 2006.
Article in English | MEDLINE | ID: mdl-17238390

ABSTRACT

Factors contributing to low adherence to clinical guidelines by clinicians are not well understood. The user interface of ATHENA-HTN, a guideline-based decision support system (DSS) for hypertension, presents a novel opportunity to collect clinician feedback on recommendations displayed at the point of care. We analyzed feedback from 46 clinicians who received ATHENA advisories as part of a 15-month randomized trial to identify potential reasons clinicians may not intensify hypertension therapy when it is recommended. Among the 368 visits for which feedback was provided, clinicians commonly reported they did not follow recommendations because: recorded blood pressure was not representative of the patient's typical blood pressure; hypertension was not a clinical priority for the visit; or patients were nonadherent to medications. For many visits, current quality-assurance algorithms may incorrectly identify clinically appropriate decisions as guideline nonadherent due to incomplete capture of relevant information. We present recommendations for how automated DSSs may help identify "apparent" barriers and better target decision support.


Subject(s)
Decision Support Systems, Clinical , Guideline Adherence , Hypertension/therapy , Practice Guidelines as Topic , Aged , Feedback , Female , Humans , Male , Physicians, Family , Point-of-Care Systems , Reminder Systems , Therapy, Computer-Assisted , User-Computer Interface
13.
J Clin Pathol ; 58(6): 640-4, 2005 Jun.
Article in English | MEDLINE | ID: mdl-15917418

ABSTRACT

BACKGROUND: Malignant melanoma arising from different body compartments may be associated with differing aetiological factors and clinical behaviour, and may manifest diverse molecular genetic profiles. Although many studies have focused on cutaneous melanoma, little is known of mucosal and other types of melanoma. In particular, malignant melanoma of soft parts is different from other melanomas in many respects, yet manifests a common melanocytic differentiation. Mutation of BRAF is now known to be common in cutaneous melanomas, and raises possible new therapeutic options of anti-RAF treatment for these patients. Few data are available for non-cutaneous melanomas. AIMS: To study the incidence of BRAF and NRAS mutations in melanomas arising in diverse internal organs. METHODS: Fifty one melanomas from various internal organs were investigated for BRAF and NRAS mutation by direct DNA sequencing. RESULTS: BRAF and NRAS mutations were found in two and five mucosal melanomas arising from the aerodigestive and female genital tracts (n = 36). Their occurrence is mutually exclusive, giving a combined mutation incidence rate of 19.4% in mucosal melanomas. Both BRAF and NRAS mutations were absent in malignant melanoma of soft parts (n = 7). BRAF mutation was also absent in uveal melanoma (n = 6), but was seen in two of five cutaneous melanomas. The incidence of BRAF or combined BRAF/NRAS mutations in all non-cutaneous groups was significantly lower than published rates for cutaneous melanomas. CONCLUSION: Each melanoma subtype may have a unique oncogenetic pathway of tumour development, and only a small fraction of non-cutaneous melanomas may benefit from anti-RAF treatment.


Subject(s)
Genes, ras/genetics , Melanoma/genetics , Mutation , Neoplasm Proteins/genetics , Proto-Oncogene Proteins B-raf/genetics , Adolescent , Adult , Aged , Aged, 80 and over , DNA Mutational Analysis , DNA, Neoplasm/genetics , Digestive System Neoplasms/genetics , Female , Genital Neoplasms, Female/genetics , Humans , Middle Aged , Skin Neoplasms/genetics , Uveal Neoplasms/genetics
14.
AMIA Annu Symp Proc ; : 505-9, 2005.
Article in English | MEDLINE | ID: mdl-16779091

ABSTRACT

We describe the use of the l1 norm for selection of a sparse set of model parameters that are used in the prediction of viral drug response, based on genetic sequence data of the Human Immunodeficiency Virus (HIV) reverse-transcriptase enzyme. We discuss the use of the l1 norm in the Least Absolute Selection and Shrinkage Operator (LASSO) regression model and the Support Vector Machine model. When tested by cross-validation with laboratory measurements, these models predict viral phenotype, or resistance, in response to Reverse-Transcriptase Inhibitors (RTIs) more accurately than other known models. The l1 norm is the most selective convex function, which sets a large proportion of the parameters to zero and also assures that a single optimal solution will be found, given a particular model formulation and training data set. A statistical model that reliably predicts viral drug response is an important tool in the selection of Anti-Retroviral Therapy. These techniques have general application to modeling phenotype from complex genetic data.


Subject(s)
Anti-Retroviral Agents/therapeutic use , Drug Resistance, Viral/genetics , HIV Reverse Transcriptase/genetics , HIV-1/genetics , Models, Statistical , Algorithms , Decision Trees , Expert Systems , Humans , Mutation , Phenotype , Regression Analysis
15.
AMIA Annu Symp Proc ; : 915, 2005.
Article in English | MEDLINE | ID: mdl-16779202

ABSTRACT

Studies of barriers to guideline adherence have generally surveyed clinicians temporally remote from the clinical scenario in which recommendations were delivered, potentially adversely biasing clinician observations. The user interface of ATHENA DSS, a guideline-based decision support system for hypertension, includes a point-of-care feedback window that accepts clinician-user comments during the display of recommendations. Analysis of this feedback has revealed a number of intriguing patient, provider, and technical barriers to adherence collected during real-time system use.


Subject(s)
Attitude of Health Personnel , Decision Support Systems, Clinical , Guideline Adherence , Hypertension/therapy , Point-of-Care Systems , Humans , Medical Records Systems, Computerized , Practice Guidelines as Topic , Randomized Controlled Trials as Topic , User-Computer Interface
16.
Stud Health Technol Inform ; 107(Pt 1): 125-9, 2004.
Article in English | MEDLINE | ID: mdl-15360788

ABSTRACT

Measurement of provider adherence to a guideline-based decision support system (DSS) presents a number of important challenges. Establishing a causal relationship between the DSS and change in concordance requires consideration of both the primary intention of the guideline and different ways providers attempt to satisfy the guideline. During our work with a guideline-based decision support system for hypertension, ATHENA DSS, we document a number of subtle deviations from the strict hypertension guideline recommendations that ultimately demonstrate provider adherence. We believe that understanding these complexities is crucial to any valid evaluation of provider adherence. We also describe the development of an advisory evaluation engine that automates the interpretation of clinician adherence with the DSS on multiple levels, facilitating the high volume of complex data analysis that is created in a clinical trial of a guideline-based DSS.


Subject(s)
Decision Support Systems, Clinical , Drug Therapy, Computer-Assisted , Guideline Adherence , Hypertension/drug therapy , Practice Guidelines as Topic , Humans , Medical Records Systems, Computerized , United States , United States Department of Veterans Affairs , User-Computer Interface
17.
Hong Kong Med J ; 9(4): 238-42, 2003 Aug.
Article in English | MEDLINE | ID: mdl-12904609

ABSTRACT

OBJECTIVE: To evaluate the feasibility and safety of cholecystectomy using miniaturised instruments of 3 mm or less in diameter. DESIGN: Prospective study on patients with gallstones, with or without related complications. SETTING: Private hospital, Hong Kong. PATIENTS: From September 1997 to September 2002, 150 of the 180 consecutive patients managed were included in the present study. MAIN OUTCOME MEASURES: All patients were operated on with a standard four-port technique. Mini-laparoscopes of different sizes were used throughout the study period, which included 2-mm (n=33) fibre-optic laparoscope, and 2.5-mm (n=61) and 3-mm (n=56) laparoscopes of Hopkins rod lens system. The cystic duct and artery were secured either by extracorporeal ties or 10-mm clips passed through the umbilicus. The time taken from dissection to division of the cystic duct and artery, and to complete the operation were documented. RESULTS: The operation was successfully completed with needlescopic instruments in 127 (85%) patients, even though patients with acute cholecystitis and history of common bile duct stones were included. Use of larger-diameter mini-laparoscopes decreased the time needed to divide the cystic duct and artery, to detach the gall bladder from the liver, and to complete the operation. There were no deaths. One minor bile duct injury developed secondary to extensive cauterisation of the gall bladder fossa. CONCLUSION: Needlescopic cholecystectomy with minor technical modification can be completed within a duration comparable to standard laparoscopy at no increased risk for the great majority of patients with gallstones.


Subject(s)
Cholecystectomy, Laparoscopic/instrumentation , Laparoscopes , Needles , Adult , Aged , Aged, 80 and over , Cholecystectomy, Laparoscopic/methods , Cholelithiasis/surgery , Female , Fiber Optic Technology/instrumentation , Hong Kong , Hospitals, General , Humans , Length of Stay , Male , Middle Aged , Miniaturization , Prospective Studies , Time Factors
18.
Eur J Neurol ; 10(3): 265-9, 2003 May.
Article in English | MEDLINE | ID: mdl-12752400

ABSTRACT

The prognosis of cerebellar hemorrhage with brain stem compression is known to be poor, and patients who can usually survive are severely disabled with limited benefit from conventional rehabilitation. An innovative cutaneous stimulation was administered to a chronic patient (2 years after the incidence) who has severe ataxia, gait imbalance and limb spasticity caused by cerebellar hemorrhage. After 8 months of intervention, patient's function as evaluated by two functional measures has improved by 40%. In addition, the patient's ataxia and hypotonia have improved significantly in which he has regained the abilities to grasp objects, sit upright, control his equilibrium, and monitor an electric wheelchair. The present case study demonstrated a significant improvement of a chronic severely disabled patient who received the intervention 2 years after the accident, suggesting that the cutaneous stimulation may be a possible effective neurologic intervention.


Subject(s)
Brain Hemorrhage, Traumatic/therapy , Electric Stimulation Therapy/methods , Skin/innervation , Adolescent , Ataxia/etiology , Brain Hemorrhage, Traumatic/pathology , Brain Hemorrhage, Traumatic/physiopathology , Cerebellar Cortex/pathology , Chronic Disease , Gait Ataxia/etiology , Humans , Magnetic Resonance Imaging , Male , Motor Activity , Muscle Spasticity/etiology , Recovery of Function , Treatment Outcome
19.
Med Vet Entomol ; 16(3): 321-7, 2002 Sep.
Article in English | MEDLINE | ID: mdl-12243234

ABSTRACT

To determine which species and populations of Anopheles transmit malaria in any given situation, immunological assays for malaria sporozoite antigen can replace traditional microscopical examination of freshly dissected Anopheles. We developed a wicking assay for use with mosquitoes that identifies the presence or absence of specific peptide epitopes of circumsporozoite (CS) protein of Plasmodium falciparum and two strains of Plasmodium vivax (variants 210 and 247). The resulting assay (VecTest Malaria) is a rapid, one-step procedure using a 'dipstick' test strip capable of detecting and distinguishing between P. falciparum and P. vivax infections in mosquitoes. The objective of the present study was to test the efficacy, sensitivity, stability and field-user acceptability of this wicking dipstick assay. In collaboration with 16 test centres world-wide, we evaluated more than 40 000 units of this assay, comparing it to the standard CS ELISA. The 'VecTest Malaria' was found to show 92% sensitivity and 98.1% specificity, with 97.8% accuracy overall. In accelerated storage tests, the dipsticks remained stable for > 15 weeks in dry conditions up to 45 degrees C and in humid conditions up to 37 degrees C. Evidently, this quick and easy dipstick test performs at an acceptable level of reliability and offers practical advantages for field workers needing to make rapid surveys of malaria vectors.


Subject(s)
Anopheles/immunology , Anopheles/parasitology , Antigens, Protozoan/immunology , Insect Vectors/immunology , Insect Vectors/parasitology , Plasmodium falciparum/immunology , Plasmodium vivax/immunology , Reagent Strips/standards , Animals , Enzyme-Linked Immunosorbent Assay , Malaria, Falciparum/transmission , Malaria, Vivax/transmission , Protozoan Proteins/immunology , Sensitivity and Specificity , Time Factors
20.
Chemotherapy ; 48(6): 303-8, 2002.
Article in English | MEDLINE | ID: mdl-12673105

ABSTRACT

BACKGROUND: The fruit extract of Gleditsia sinensis Lam. (GSE) is a traditional herbal medicine that is saponin-rich. However, its activity on solid tumour cell lines has never been demonstrated. METHODS: The activity of GSE was demonstrated in four cancer cell lines (breast cancer MCF-7, MDA-MB231, hepatoblastoma HepG2 and oesophageal squamous carcinoma cell line SLMT-1) using MTT assay, anchorage-independent clonogenicity assay, DNA laddering and in situ cell death detection. RESULTS: The mean MTT(50) (the mean concentration of GSE to reduce MTT activity by 50%) ranged from 16 to 20 microg/ml of GSE. An anchorage-independent clonogenicity assay showed that all of the four solid tumour cell lines gradually lost their regeneration potential after treatment with GSE, DNA fragmentation and TUNEL analysis demonstrated that the action of GSE is both dose- and time course-dependent. CONCLUSIONS: Our results suggest that GSE has a cytotoxic activity and can induce apoptosis in human solid tumour cell lines.


Subject(s)
Antineoplastic Agents, Phytogenic/pharmacology , Gleditsia/chemistry , Apoptosis , Cell Division/drug effects , Drug Screening Assays, Antitumor , Fruit , Humans , Plant Extracts/pharmacology , Tumor Cells, Cultured , Tumor Stem Cell Assay
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