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1.
Stud Health Technol Inform ; 280: 81-85, 2021 Jun 28.
Article in English | MEDLINE | ID: mdl-34190065

ABSTRACT

The aims of this study were to evaluate the effect of a thoracoplasty procedure in addition to a posterior spinal fusion and instrumentation on an Adolescent Idiopathic Scoliosis (AIS) patient's 3D back contour as measured by surface topography. We performed a retrospective review to identify patients who were treated with posterior spinal fusion with spinal instrumentation and those who were treated with an additional thoracoplasty procedure. We analyzed changes in surface topography measurements between these two groups using t-test and ANCOVA statistical analyses. Although there were no statistically significant differences in 11 of 12 variables, thoracoplasty-posterior spinal fusion (n=10) group had a mean 6.6 unit reduction in trunk asymmetry while the posterior spinal fusion group (n=26) had a mean 22.8 unit reduction in trunk asymmetry (p-value<0.05). The posterior spinal fusion group and thoracoplasty-posterior spinal fusion group were not shown to have clinically significant differences in 3D back contour correction. An additional thoracoplasty procedure does not provide better correction in the transverse plane and in fact had a smaller degree of trunk asymmetry correction. This supports the current trends of decreasing use of thoracoplasty in AIS patients to address severe rib hump deformities given concerns for decreased post-operative lung function and alternative methods of vertebral body derotation, such as thoracic pedicle screws.


Subject(s)
Scoliosis , Spinal Fusion , Thoracoplasty , Adolescent , Bone Screws , Humans , Retrospective Studies , Scoliosis/surgery , Treatment Outcome
2.
Stud Health Technol Inform ; 280: 131-135, 2021 Jun 28.
Article in English | MEDLINE | ID: mdl-34190074

ABSTRACT

Adolescent idiopathic scoliosis (AIS) has been postulated to affect gait patterns and postural stability due to its effect on center of body mass. 1) Determine the correlation between Cobb angle and COP in the anterior-posterior (AP) direction, COP in the medial-lateral (ML) direction, COP oscillation (COP-O) from midline walking, peak pressures, and pressure-time integrals (loading) at 10 anatomic foot segments; 2) Determine the differences in COP-AP, COP-ML, COP-O, and peak plantar pressures at 10 anatomic foot segments between the normal group and the AIS group. All patients wore a gown to expose the posterior trunk and underwent evaluation with Formetric 4D (DIERS International GmbH, Schlangenbad, Germany) while walking on the treadmill at 2 km/hour for 15 seconds. A total of 24 pressure metrics at 10 anatomic foot segments were evaluated. We then analyzed the data using t-test and linear regression analyses.16 patients were assigned to a normal group (Cobb angle 10° or less, n=4) or AIS group (Cobb greater than 10°, n=12). Of note, AIS patients had statistically significant lower max. pressures at the hallux and the 2nd, 4th, 5th metatarsal head compared to the normal group. Additionally, there was a statistically significant linear association between Cobb angle and both hallux max. pressure and hallux pressure-time integral (P<0.05). Reduced peak plantar pressures before the toe-off phase of gait cycle indicate that AIS patients may lean backwards and have posterior postural sway, which may be associated with hypokyphosis during walking.


Subject(s)
Scoliosis , Adolescent , Foot , Gait , Germany , Humans , Walking
3.
Osteoporos Int ; 32(9): 1895-1898, 2021 Sep.
Article in English | MEDLINE | ID: mdl-33655402

ABSTRACT

Phosphaturic mesenchymal tumors (PMTs) can present with vague symptoms of diffuse bone pain with pathologic fractures that often lead to a delayed diagnosis. We present a 60-year-old patient with a PMT that was persistently hypophosphatemic after resection, who was then successfully treated with cryoablation of the tumor. Tumor-induced osteomalacia (TIO) is a rare cause of hypophosphatemia characterized by vague symptoms of gradual muscle weakness and diffuse bone pain with pathologic fractures that often lead to a delayed diagnosis. This condition is usually caused by benign phosphaturic mesenchymal tumors (PMTs). Here, we present a case of persistent PMT after surgical resection treated with image-guided ablation. We present the patient's clinical examinations and laboratory findings (phosphorus, 1,25 (OH)2D, FGF-23, Intact PTH). Representative histologic images of a PMT are also presented. A 61-year-old male was evaluated for persistent hypophosphatemia and presumed osteomalacia. Six years earlier, he underwent surgical excision of a left ischial mass after presenting with TIO. The pathology was consistent with a PMT; however, hypophosphatemia persisted suggesting incomplete resection. He was treated with calcitriol and phosphate salts. A PET Ga68 dotatate scan of the patient revealed an avid left ischial mixed lytic and sclerotic lesions with marked amount of radiotracer uptake, suggesting persistent tumor. The patient was resistant to re-excision of the tumor due to the extended recovery period from his prior surgery and was treated instead with cryoablation of the tumor. His biochemical findings of hypophosphatemia and elevated FGF23 resolved after the ablation and have remained normal for 5 months after surgery. In patients with TIO, wide surgical excision is the treatment of choice. When this is not possible, image-guided ablation is an alternative therapeutic option.


Subject(s)
Hypophosphatemia , Neoplasms, Connective Tissue , Osteomalacia , Soft Tissue Neoplasms , Fibroblast Growth Factor-23 , Humans , Hypophosphatemia/etiology , Male , Middle Aged , Neoplasms, Connective Tissue/complications , Neoplasms, Connective Tissue/diagnostic imaging , Neoplasms, Connective Tissue/surgery , Osteomalacia/etiology , Osteomalacia/surgery , Paraneoplastic Syndromes , Soft Tissue Neoplasms/complications , Soft Tissue Neoplasms/diagnostic imaging , Soft Tissue Neoplasms/surgery
4.
Osteoporos Int ; 29(4): 973-985, 2018 04.
Article in English | MEDLINE | ID: mdl-29383389

ABSTRACT

Is gout a risk factor for future osteoporosis? This large population-based study comprising two matched groups of individuals with and without gout demonstrates that patients with gout have a 20% increase in the risk of developing osteoporosis in future through an 8-year follow-up. INTRODUCTION: To examine if gout is associated with an increased risk of osteoporosis. METHODS: We conducted a nationwide population-based retrospective matched-cohort study. Two matched cohorts (n = 36,458 with gout and 71,602 without gout) assembled and recruited from the Longitudinal Health Insurance Dataset containing 1 million subjects. Exclusion criteria were missing data, age < 20 years, short follow-up period, and pre-existing osteoporosis. Both cohorts were followed up until incident osteoporosis, death, or the end of the study. Person-year data and incidence rates were evaluated. A multivariable Cox model was used to derive an adjusted hazard ratio (aHR) after controlling for socioeconomic proxy, geographical difference, glucocorticoid and allopurinol exposure, various prespecified medical conditions, and comorbidities. RESULTS: Men comprised 72.8% of the cohorts. With a follow-up of 183,729 and 359,900 person-years for the gout and non-gout cohorts, 517 and 811 incidents of osteoporosis occurred, respectively, after excluding osteoporosis incidents in the first 3 years of follow-up. The cumulative incidence of osteoporosis was statistically higher in the gout cohort than in the non-gout cohort, at 3.3 versus 2.1% (P = 0.0036, log-rank). Our Cox model showed a 1.2-fold increase in the incidence of osteoporosis in the gout cohort, with an aHR of 1.2 (95% confidence interval, 1.06-1.35). CONCLUSIONS: This first population-based epidemiologic study supports the hypothesis that compared with individuals without gout; those with gout have a modest increase in the risk of developing osteoporosis in future.


Subject(s)
Gout/epidemiology , Osteoporosis/epidemiology , Adult , Age Distribution , Aged , Aged, 80 and over , Female , Follow-Up Studies , Gout/complications , Humans , Incidence , Male , Middle Aged , Osteoporosis/etiology , Osteoporotic Fractures/epidemiology , Osteoporotic Fractures/etiology , Proportional Hazards Models , Retrospective Studies , Risk Factors , Sex Distribution , Taiwan/epidemiology , Young Adult
5.
J Biomater Appl ; 31(2): 215-29, 2016 08.
Article in English | MEDLINE | ID: mdl-27422714

ABSTRACT

Ti-C:H coatings were deposited on original, nitrided, and polished-nitrided AISI 316L stainless steel substrates using a closed field unbalanced magnetron sputtering system. Sliding friction wear tests were performed in 0.89 wt.% NaCl solution under a load of 30 N against AISI 316L stainless steel, Si3N4, and Ti6Al4V balls, respectively. The electrochemical properties of the various specimens were investigated by means of corrosion tests performed in 0.89 wt.% NaCl solution at room temperature. Finally, the biocompatibility properties of the specimens were investigated by performing cell culturing experiments using purified mouse leukemic monocyte macrophage cells (Raw264.7). In general, the results showed that plasma nitriding followed by Ti-C:H coating deposition provides an effective means of improving the wear resistance, anti-corrosion properties, and biocompatibility performance of AISI 316L stainless steel.


Subject(s)
Coated Materials, Biocompatible/chemistry , Electrochemistry/methods , Stainless Steel/chemistry , Titanium/chemistry , Alloys , Animals , Carbon Compounds, Inorganic/chemistry , Cell Adhesion , Cell Proliferation , Corrosion , Materials Testing , Mice , Plasma Gases , Prostheses and Implants , RAW 264.7 Cells , Silicon Compounds/chemistry , Spectrum Analysis, Raman , Surface Properties , Wettability , X-Ray Diffraction
6.
Andrology ; 3(5): 895-901, 2015 Sep.
Article in English | MEDLINE | ID: mdl-26227297

ABSTRACT

Evidence from our previous study suggested that the incidence of germ cell neoplasms in children and adolescents is increasing. The objectives of this analysis were to quantify this trend in patients aged 0-9 and 10-19 years (pre-pubertal and adolescent groups, respectively) and compare rates in Taiwan according to geographic distribution. Germ cell neoplasm frequencies among 1267 patients aged 0-19 years spanning 1995-2009 were obtained from the population-based Taiwan Cancer Registry. The incidence patterns according to sex, age, disease subgroup, and geographic distribution were analyzed. The incidence rates in the pre-pubertal and adolescent groups were 10.58 and 16.06 per million person-years, respectively. The overall rates increased significantly by 3.2% annually in the adolescent group during the 15-year study period, and increased only among the males. In contrast, no change in trend was observed in the pre-pubertal group. Subgroup analysis showed significant upward trends in the incidence rates of intracranial/intraspinal and testicular germ cell tumors (GCTs) in the adolescent males and extracranial/extragonadal GCTs in the pre-pubertal boys. The most striking differences between the study population and white Americans were that the rates of testicular GCTs were 5-fold higher and 4-fold lower in the Taiwanese pre-pubertal and adolescent groups, respectively. Significantly higher rates were found in Hualien and Chiayi Counties compared with the other areas of Taiwan. The upward trend of testicular GCTs in the adolescent males is consistent with findings from Western countries. The underlying causes that led to the high rate of testicular GCTs in the pre-pubertal boys and significantly higher rates in specific counties warrant further investigation.


Subject(s)
Geography/trends , Neoplasms, Germ Cell and Embryonal/epidemiology , Testicular Neoplasms/epidemiology , Adolescent , Adult , Age Factors , Asian People , Child , Child, Preschool , Humans , Incidence , Infant , Infant, Newborn , Male , Sex Factors , Taiwan/epidemiology , White People , Young Adult
7.
Invest Ophthalmol Vis Sci ; 54(5): 3224-33, 2013 May 07.
Article in English | MEDLINE | ID: mdl-23580482

ABSTRACT

PURPOSE: A fish scale-derived collagen matrix (FSCM) is proposed as an alternative for human donor corneal tissue. Light scatter and light transmission of the FSCM were measured and compared with human cornea, and its short-term biocompatibility was tested in a rat model. METHODS: light scatter was determined with a straylight measuring device, whereas light transmission was measured using a broadband absorption spectrometer. for evaluation of the biocompatibiliy, three approaches were used: the FSCM was implanted as an anterior lamellar keratoplasty (ALK), placed in an interlamellar corneal pocket (IL), and placed subconjunctivally (SC). Transparency, neovascularization, and epithelial damage were followed for 21 days. Morphology and cellular infiltration were assessed histologically. RESULTS: The amount of scattered light was comparable to that seen in early cataract and the percentage of light transmission was similar to the transmission through the human cornea. Implantation of the FSCM as an ALK led to mild haziness only, not obscuring the pupil, despite the development of neovascularization around the sutures; IL placement led to a moderate haze, partly obscuring the pupil, and to (partial) melting of the anterior corneal lamella. The SC group exhibited local swelling and induration, which decreased over time. Histology showed a chronic inflammation varying from mild and moderate in the ALK and IL group, to severe in the SC group. CONCLUSIONS: In spite of technical difficulties, it was feasible to use the FSCM for ALK, whereas IL placement led to melting of the anterior lamella. Further studies are necessary for better understanding of its immunogenicity. The light scatter and transmission data show that the first version of this FSCM is comparable to human cornea tissue in this respect.


Subject(s)
Artificial Organs , Collagen Type I/chemistry , Cornea , Extracellular Matrix/transplantation , Keratoplasty, Penetrating , Tilapia , Animals , Biocompatible Materials , Extracellular Matrix/chemistry , Extracellular Matrix/physiology , Graft Survival , Humans , Light , Male , Materials Testing , Microscopy, Phase-Contrast , Rats , Rats, Inbred F344 , Scattering, Radiation , Suture Techniques , Tissue Donors , Tissue Scaffolds
8.
J Int Med Res ; 40(6): 2311-20, 2012.
Article in English | MEDLINE | ID: mdl-23321188

ABSTRACT

OBJECTIVES: Prior research has focused on the relationship between weight change and incidence of metabolic syndrome. Change in body mass index (BMI), components of metabolic syndrome and metabolic syndrome status were investigated over 1 year of follow-up. METHODS: Subjects with metabolic syndrome from a community health screening project were recruited. Logistic regression was used to analyse the disappearance or remission of metabolic syndrome during 1 year according to changes in BMI, waist circumference, triglycerides, blood pressure, high-density lipoprotein-cholesterol (HDL-C) and fasting plasma glucose (FPG). RESULTS: The study included 490 subjects with metabolic syndrome. After 1 year, metabolic syndrome had disappeared in 30.0% (147/490) of subjects. Decreased triglycerides, blood pressure and HDL-C were significantly associated with the 1-year disappearance of metabolic syndrome, whereas BMI, waist circumference and FPG levels were not. CONCLUSIONS: Short-term weight reduction has no impact on the status of metabolic syndrome. The disappearance of metabolic syndrome was common during a 1-year follow-up. This finding might impact on the treatment and management of people with metabolic syndrome.


Subject(s)
Metabolic Syndrome/blood , Weight Loss , Adult , Aged , Blood Glucose , Blood Pressure , Body Composition , Body Mass Index , Body Weight , Female , Humans , Lipoproteins, HDL/blood , Male , Middle Aged , Triglycerides/blood , Waist Circumference
9.
Biol Res Nurs ; 12(2): 198-205, 2010 Oct.
Article in English | MEDLINE | ID: mdl-20031954

ABSTRACT

Inflammatory response secondary to hemorrhagic shock (HS) frequently precedes multiple organ failure and death in trauma patients. Researchers have recognized that exercise benefits immune function. However, the effects of exercise on HSinduced death and organ damage are unknown. In this study, the authors aimed to explore the effects of exercise on survival rate and organ injury after HS. Rats were divided into exercise and nonexercise groups. The exercise group received running training 30 min/day five times/week for 4 weeks. After 4 weeks, researchers withdrew 60% of total blood volume in both groups to mimic HS. Levels of blood aspartate transferase (GOT), alanine transferase (GPT), blood urea nitrogen (BUN), creatinine (Cr), lactic acid dehydrogenase (LDH), creatine kinase-myoglobin (CK-MB), blood glucose, and lactate were measured. The survival rate and injury scores for the liver, kidney, and lung were examined 48 hr after HS. Physical activity was measured in surviving rats from the 3rd to the 7th day after HS. Exercise training significantly increased the survival rate (75% for the exercise group vs. 50% for the nonexercise group) after HS and decreased organ injury. In addition, the exercise group was more active than the nonexercise group after HS.


Subject(s)
Physical Conditioning, Animal , Shock, Hemorrhagic/physiopathology , Animals , Bronchoalveolar Lavage Fluid , Rats , Survival Rate
10.
Hum Hered ; 68(4): 278-87, 2009.
Article in English | MEDLINE | ID: mdl-19622894

ABSTRACT

OBJECTIVE: The performance of association tests based on case-control or case-parents substudy alone can be improved by jointly using genetic data from two substudies. However, genetic data from different sources may not be combinable due to population stratification. We propose a two-stage association test based on using combinability tests in stage 1 and association tests in stage 2. METHODS: The combinability tests are designed for testing that genotype data from different sources have same genotype frequencies and relative risks. The association tests are well known tests in the literature. We propose a method to adjust the significance levels at two stages so that the overall type I error rate of the two-stage test can be controlled at the desired level. RESULTS: The simulation results confirm that the two-stage test has empirical type I error rates approximately equal to the predetermined levels while making substantially fewer false negatives than the usual test based only on case-parents substudy. CONCLUSION: It is advantageous to combinecase-control and case-parents data into a single analysis.The two-stage test has significant power improvement when the family-based test has weak or moderate power performance and is robust to the effect of population stratification.


Subject(s)
Genetic Predisposition to Disease , Genetic Techniques , Parents , Case-Control Studies , Humans , Models, Genetic
11.
Oncogene ; 27(42): 5578-89, 2008 Sep 18.
Article in English | MEDLINE | ID: mdl-18504433

ABSTRACT

A comprehensive microarray analysis of hepatocellular carcinoma (HCC) revealed distinct synexpression patterns during intrahepatic metastasis. Recent evidence has demonstrated that synexpression group member genes are likely to be regulated by master control gene(s). Here we investigate the functions and gene regulation of the transcription factor SOX4 in intrahepatic metastatic HCC. SOX4 is important in tumor metastasis as RNAi knockdown reduces tumor cell migration, invasion, in vivo tumorigenesis and metastasis. A multifaceted approach integrating gene profiling, binding site computation and empirical verification by chromatin immunoprecipitation and gene ablation refined the consensus SOX4 binding motif and identified 32 binding loci in 31 genes with high confidence. RNAi knockdown of two SOX4 target genes, neuropilin 1 and semaphorin 3C, drastically reduced cell migration activity in HCC cell lines suggesting that SOX4 exerts some of its action via regulation of these two downstream targets. The discovery of 31 previously unidentified targets expands our knowledge of how SOX4 modulates HCC progression and implies a range of novel SOX4 functions. This integrated approach sets a paradigm whereby a subset of member genes from a synexpression group can be regulated by one master control gene and this is exemplified by SOX4 and advanced HCC.


Subject(s)
Carcinoma, Hepatocellular/pathology , Liver Neoplasms/pathology , Oligonucleotide Array Sequence Analysis/methods , SOXC Transcription Factors/physiology , Animals , Cell Line, Tumor , Cell Movement , Chromatin Immunoprecipitation , Gene Expression Profiling , Humans , Mice , Neoplasm Invasiveness , Neoplasm Metastasis , Neuropilin-1/genetics , Phylogeny , RNA, Small Interfering/genetics , SOXC Transcription Factors/antagonists & inhibitors , SOXC Transcription Factors/genetics , Semaphorins/genetics
12.
Evol Comput ; 9(4): 421-43, 2001.
Article in English | MEDLINE | ID: mdl-11709103

ABSTRACT

A robust evolutionary approach, called the Family Competition Evolutionary Algorithm (FCEA), is described for the synthesis of optical thin-film designs. Based on family competition and adaptive rules, the proposed approach consists of global and local strategies by integrating decreasing mutations and self-adaptive mutations. The method is applied to three different optical coating designs with complex spectral quantities. Numerical results indicate that the proposed approach performs very robustly and is very competitive with other approaches.


Subject(s)
Algorithms , Optics and Photonics , Numerical Analysis, Computer-Assisted
13.
DNA Cell Biol ; 20(5): 249-55, 2001 May.
Article in English | MEDLINE | ID: mdl-11410161

ABSTRACT

A zebrafish sodium channel cDNA encoding a 1949-amino acid polypeptide, Na(v)1.6, was isolated. Two transcripts were detected in zebrafish adult brain but not in cardiac or skeletal muscle. The RNase protection analysis confirmed the neural specificity of zebrafish Na(v)1.6 24 hours postfertilization (hpf) Na(v)1.6 was expressed in the trigeminal ganglion, anterior and posterior lateral line ganglia, rhombomeres, and Rohon-Beard neurons. This preferential localization suggests that Na(v)1.6 plays an important role in tactile sensitivity. The abundance of zebrafish Na(v) 1.6 mRNA in the central and peripheral nervous systems increased markedly between 48 and 72 hpf, during the maturation of the nervous system.


Subject(s)
Neurons, Afferent/metabolism , Sodium Channels/chemistry , Sodium Channels/metabolism , Zebrafish Proteins , Zebrafish/metabolism , Amino Acid Sequence , Animals , Brain/metabolism , Cloning, Molecular , Embryo, Nonmammalian/metabolism , Ganglia, Spinal/chemistry , Ganglia, Spinal/cytology , Ganglia, Spinal/metabolism , Immunohistochemistry , In Situ Hybridization , Molecular Sequence Data , Neurons, Afferent/chemistry , Phylogeny , Protein Conformation , Retinal Ganglion Cells/chemistry , Retinal Ganglion Cells/metabolism , Sodium Channels/genetics , Superior Colliculi/chemistry , Superior Colliculi/metabolism , Touch , Zebrafish/embryology , Zebrafish/genetics , Zebrafish/growth & development
14.
Proteins ; 42(2): 237-42, 2001 Feb 01.
Article in English | MEDLINE | ID: mdl-11119648

ABSTRACT

The molten globule state of alpha-lactalbumin (alpha LA) has served as a paradigm for understanding the role of these partially folded states in protein folding. We previously showed that a peptide construct consisting of the A and B helices (residues 1-38) cross-linked to the D- and C-terminal 3(10) helices (residues 101-120) of alpha LA is capable of folding to a stable molten globule-like state. Here, we report the study of three peptide constructs that are designed to investigate the contribution two short hydrophobic sequences located near the C-terminus of alpha LA make to the structure and stability of the alpha LA molten globule state. These regions of the protein have been shown to form stable non-native structures in isolation. The three peptide constructs contain residues 1-38 cross-linked to three separate C-terminal peptides via the native 28-111 disulfide bond. The C-terminal peptides consist of residues 101-114, 106-120, and 106-114. The results of CD, fluorescence, ANS binding, and urea denaturation experiments indicate that constructs that lack either of the hydrophobic sequences (residues 101-105 and 115-120) are significantly less structured. These results highlight the importance of long-range, mutually stabilizing interactions within the molten globule state of the protein. Proteins 2001;42:237-242.


Subject(s)
Lactalbumin/chemistry , Amino Acid Sequence , Circular Dichroism , Humans , Models, Molecular , Molecular Sequence Data , Peptides/chemical synthesis , Peptides/chemistry , Protein Conformation , Protein Denaturation , Protein Folding
15.
J Dairy Sci ; 84(11): 2419-23, 2001 Nov.
Article in English | MEDLINE | ID: mdl-11768082

ABSTRACT

Coryneform bacteria are frequently isolated from bovine mastitis with the lipophilic species, and Corynebacterium bovis is the most frequently isolated organism of this group. However, previous studies on the phylogeny of corynebacteria have incorporated only a single reference strain. We examined the phylogeny of C. bovis using 47 strains isolated from bovine mammary glands. Phylogenetic studies were performed by direct sequencing of the 16S ribosomal RNA and comparison to sequences of reference strains. All strains identified as C. bovis demonstrated similarity of 98% or higher to the ribosomal RNA gene sequences of the type strain of C. bovis. Phylogenetic analyses indicated that all strains tested clustered with members of the Corynebacterium urealyticum group confirming that C. bovis is a legitmate member of the genus Corynebacterium. Further investigation into the diversity within the species using repetitive element palindrome PCR indicated only minor differences between the strains tested. Corynebacterium bovis ATCC 13722 demonstrated the highest similarity (95%) with Brevibacterium helvolum, indicating that this organism does not belong in the genus Corynebacterium.


Subject(s)
Corynebacterium/classification , Mammary Glands, Animal/microbiology , Mastitis, Bovine/microbiology , RNA, Ribosomal, 16S/genetics , Animals , Cattle , Corynebacterium/genetics , Female , Molecular Sequence Data , Phylogeny , Polymerase Chain Reaction/veterinary , Sequence Analysis
16.
Int J Neural Syst ; 10(5): 333-52, 2000 Oct.
Article in English | MEDLINE | ID: mdl-11195934

ABSTRACT

In this paper, we present a new evolutionary technique to train three general neural networks. Based on family competition principles and adaptive rules, the proposed approach integrates decreasing-based mutations and self-adaptive mutations to collaborate with each other. Different mutations act as global and local strategies respectively to balance the trade-off between solution quality and convergence speed. Our algorithm is then applied to three different task domains: Boolean functions, regular language recognition, and artificial ant problems. Experimental results indicate that the proposed algorithm is very competitive with comparable evolutionary algorithms. We also discuss the search power of our proposed approach.


Subject(s)
Algorithms , Artificial Intelligence , Genetics/education , Neural Networks, Computer , Animals , Chromosomes/genetics , Humans , Language , Models, Biological , Mutation/physiology , Normal Distribution
17.
IEEE Trans Image Process ; 8(12): 1831-4, 1999.
Article in English | MEDLINE | ID: mdl-18267460

ABSTRACT

The covariance matrix of a pattern is composed by its second order central moments. For a rotationally symmetric shape, its covariance matrix is a scalar identity matrix. In this work, we apply this property to restore the skewed shape of rotational symmetry. The relations between the skew transformation matrix and the covariance matrices of original and skewed shapes are derived. By computing the covariance matrix of the skewed shape and letting the covariance matrix of the original shape be a scalar identity matrix, the skew transformation matrix can be solved. Then, the rotationally symmetric shape can be recovered by multiplying the inverse transformation matrix with the skewed shape. The method does not rely on continuous contours and is robust to noise, because only the second-order moments of the input shape are required. Experimental results are also presented.

18.
Occup Environ Med ; 55(8): 573-6, 1998 Aug.
Article in English | MEDLINE | ID: mdl-9849547

ABSTRACT

OBJECTIVES: Risk factors for increased blood lead concentration (BPb) has been investigated. However, the effect of sibship and Chinese herbal medicine on BPb has not been systematically studied. In this study BPb data from voluntary testing was used to determine if Chinese herbal medicine and sibship were associated with BPb. METHODS: 319 children aged 1-7 were tested for BPb. Meanwhile, parents were interviewed to obtain information including consumption of Chinese herbal medicine, living environment, lifestyle, and sibship of the children tested. RESULTS: The mean (SD) BPb of 319 preschool children was 4.4 (2.4) micrograms/dl. The consumption of Ba-baw-san (a Chinese herbal medicine) was significantly associated with increased BPb in children (p = 0.038). Further multivariate regression analysis of BPb in 50 pairs of siblings showed the factors of being brothers explained 75% of variation for BPb, and being sisters and brother-sister explained 51% and 41% of variation respectively. CONCLUSION: Chinese herbal medicine and children's play patterns within the family expressed in different types of sibship are the main determinants of low concentrations of BPb in preschool children of Taiwan.


Subject(s)
Drugs, Chinese Herbal/adverse effects , Family Health , Lead/blood , Sibling Relations , Age Factors , Animals , Anthropometry , Child , Child, Preschool , Environment , Female , Humans , Infant , Male , Milk , Play and Playthings , Risk Factors , Sex Factors
19.
Methods ; 16(2): 150-9, 1998 Oct.
Article in English | MEDLINE | ID: mdl-9790861

ABSTRACT

Neuroendocrine PC12 cells contain small microvesicles that closely resemble synaptic vesicles in their physical and chemical properties. Two defining characteristics of synaptic vesicles are their homogeneous size and their unique protein composition. Since synaptic vesicles arise by endocytosis from the plasma membrane, nerve terminals and PC12 cells must contain the molecular machinery to sort synaptic vesicles from other membrane proteins and pinch off vesicles of the correct diameter from a precursor compartment. A cell-free reconstitution system was developed that generates vesicles from PC12 membrane precursors in the presence of ATP and brain cytosol and is temperature dependent. At 15 degrees C, surface-labeled synaptic vesicle proteins accumulate in a donor compartment, while labeled synaptic vesicles cannot be detected. The block of synaptic vesicle formation at 15 degrees C enables the use of the monoclonal antibody, KT3, a specific marker for the epitope-tagged synaptic vesicle protein, VAMP-TAg, to label precursors in the synaptic vesicle biogenesis pathway. From membranes labeled in vivo at 15 degrees C, vesicles generated in vitro at 37 degreesC had the sedimentation characteristics of neuroendocrine synaptic vesicles on glycerol velocity gradients, and excluded the transferrin receptor. Therefore, vesiculation and sorting can be studied in this cell-free system.


Subject(s)
Cell Membrane/metabolism , Endocytosis , Neurosecretory Systems/metabolism , Synaptic Vesicles/metabolism , Adenosine Triphosphate/metabolism , Animals , Brain/metabolism , Centrifugation, Density Gradient , Cytosol/metabolism , Membrane Proteins/isolation & purification , Nerve Tissue Proteins/isolation & purification , PC12 Cells , R-SNARE Proteins , Rats , Subcellular Fractions/metabolism
20.
Vision Res ; 38(18): 2761-8, 1998 Sep.
Article in English | MEDLINE | ID: mdl-9775324

ABSTRACT

Vergence eye movements have traditionally been considered the product of a single neural control center and are usually studied by combining the movements of each eye into a single 'vergence' response. In the present experiment, disparity-driven eye movements were produced by symmetrical step stimuli, and the dynamic properties of each eye movement were analyzed separately. Although the final positions of the two eyes were symmetrical, large dynamic asymmetries often occurred. The timing between the two eyes showed fair synchrony as they attained maximum velocity at approximately the same time. Since the final static positions were symmetrical, asymmetries occurring during the initial dynamic component must necessarily be compensated by offsetting asymmetries in the latter portion of the response.


Subject(s)
Convergence, Ocular , Vision Disparity , Adult , Humans , Middle Aged , Psychological Tests , Saccades
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