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1.
Biol Sport ; 31(1): 73-9, 2014 Mar.
Article in English | MEDLINE | ID: mdl-25187675

ABSTRACT

The study investigated the effect of high- and low-intensity exercise training on inflammatory reaction of blood and skeletal muscle in streptozotocin (STZ)-induced diabetic male Sprague-Dawley rats (243 ± 7 g, 8 weeks). The rats completed treadmill running in either high-intensity exercise (6 weeks of exercise training, acute bouts of exercise) or low-intensity exercise (6 weeks of exercise training). Non-running, sedentary rats served as controls. To induce diabetes mellitus, rats received a peritoneal injection of STZ (50 mg · kg(-1)). Rats were sacrificed immediately after an acute bout of exercise and 6 weeks of exercise training. Inflammatory factors were analyzed by ELISA and by immune blotting from the soleus and extensor digitorum longus muscles. In the serum, inflammatory cytokines (IL-1ß, TNF-α, IL-6, IL-4) and reactive oxygen species (ROS) (nitric oxide and malondialdehyde) increased in diabetic rats. However, all exercise training groups displayed reduced inflammatory cytokines and reactive oxygen species. In skeletal muscles, low-intensity exercise training, but not high intensity exercise, reduced the levels of COX-2, iNOS, and MMP-2, which were otherwise markedly elevated in the presence of STZ. Moreover, the levels of GLUT-4 and MyoD were effectively increased by different exercise intensity and exercise duration. Low-intensity exercise training appeared most effective to reduce diabetes-related inflammation. However, high-intensity training also reduced inflammatory factors in tissue-specific muscles. The data implicate regular exercise in protecting against chronic inflammatory diseases, such as diabetes.

2.
ACS Appl Mater Interfaces ; 6(14): 11295-301, 2014 Jul 23.
Article in English | MEDLINE | ID: mdl-24950122

ABSTRACT

High-power, long-life carbon-coated TiO2 microsphere electrodes were synthesized by a hydrothermal method for sodium ion batteries, and the electrochemical properties were evaluated as a function of carbon content. The carbon coating, introduced by sucrose addition, had an effect of suppressing the growth of the TiO2 primary crystallites during calcination. The carbon coated TiO2 (sucrose 20 wt % coated) electrode exhibited excellent cycle retention during 50 cycles (100%) and superior rate capability up to a 30 C rate at room temperature. This cell delivered a high discharge capacity of 155 mAh g(composite)(-1) at 0.1 C, 149 mAh g(composite)(-1) at 1 C, and 82.7 mAh g(composite)(-1) at a 10 C rate, respectively.

3.
Clin Radiol ; 68(9): e484-90, 2013 Sep.
Article in English | MEDLINE | ID: mdl-23684519

ABSTRACT

AIM: To compare the reliability of the conventional ultrasonography grading system for hydronephrosis as suggested by the Society for Fetal Urology (SFU) in 1993 and that developed by Onen in 2007. MATERIALS AND METHODS: One hundred and eighty kidneys in 90 paediatric patients were assessed by four radiologists using each of the two grading systems twice. The SFU system was graded 0-4 (0 = no hydronephrosis; 1 = visualized only renal pelvis; 2 = plus a few caliceal dilatation; 3 = all calyceal dilatation; 4 = plus parenchymal thinning). The Onen system was graded 0-4 (0 = no hydronephrosis; 1 = only renal pelvic dilatation; 2 = plus caliceal dilatation; 3 = plus <50% renal parenchymal loss; 4 = plus >50% renal parenchymal loss). Cohen's kappa statistic was used to estimate intra- and interobserver agreement. The weighted least-squares approach was used to compare the intra-observer agreement, and bootstrapping was used to compare the interobserver agreement between the two systems. RESULTS: Intra-observer agreement was substantial to almost perfect in both the SFU (κ 0.79-0.95) and the Onen (κ 0.66-0.97) grading system without difference. The overall interobserver agreement was substantial in both the SFU (κ 0.61-0.68) and the Onen (κ 0.66-0.76) grading system. However, interobserver agreement was fair to moderate for SFU grades 1 and 2 and Onen grades 2 and 3. CONCLUSION: Both the SFU and Onen grading system are reliable with good intra- and interobserver agreement. However, decreased interobserver agreement was demonstrated for SFU grades 1 and 2 and Onen grades 2 and 3.


Subject(s)
Hydronephrosis/diagnostic imaging , Adolescent , Child , Child, Preschool , Dilatation, Pathologic/diagnostic imaging , Dilatation, Pathologic/pathology , Humans , Hydronephrosis/pathology , Infant , Observer Variation , Reproducibility of Results , Retrospective Studies , Ultrasonography
4.
Breast Cancer Res Treat ; 136(1): 209-20, 2012 Nov.
Article in English | MEDLINE | ID: mdl-22965832

ABSTRACT

Genome-wide association studies (GWAS) have identified various genetic susceptibility loci for breast cancer based mainly on European-ancestry populations. Differing linkage disequilibrium patterns exist between European and Asian populations, and thus GWAS-identified single nucleotide polymorphisms (SNPs) in one population may not be of significance in another population. In order to explore the role of breast cancer susceptibility variants in a Chinese population of Southern Chinese descent, we analyzed 22 SNPs for 1,191 breast cancer cases and 1,534 female controls. Associations between the SNPs and clinicopathological features were also investigated. In addition, we evaluated the combined effects of associated SNPs by constructing risk models. Eight SNPs were associated with an elevated breast cancer risk. Rs2046210/6q25.1 increased breast cancer risk via an additive model [per-allele odds ratio (OR) = 1.43, 95 % confidence interval (CI) = 1.26-1.62], and was associated with estrogen receptor (ER)-positive (per-allele OR = 1.39, 95 % CI = 1.20-1.61) and ER-negative (per-allele OR = 1.55, 95 % CI = 1.28-1.89) disease. Rs2046210 was also associated with stage 1, stage 2, and stage 3 disease, with per-allele ORs of 1.38 (1.14-1.68), 1.48 (1.25-1.74), and 1.58 (1.28-1.94), respectively. Four SNPs mapped to 10q26.13/FGFR2 were associated with increased breast cancer risk via an additive model with per-allelic risks (95 % CI) of 1.26 (1.12-1.43) at rs1219648, 1.22 (1.07-1.38) at rs2981582, 1.21 (1.07-1.36) at rs2981579, and 1.18 (1.04-1.35) at rs11200014. Variants of rs7696175/TLR1, TLR6, rs13281615/8q24, and rs16886165/MAP3K1 were also associated with increased breast cancer risk, with per-allele ORs (95 % CI) of 1.16 (1.00-1.34), 1.15 (1.02-1.29), and 1.15 (1.01-1.29), respectively. Five SNPs associated with breast cancer risk predominantly among ER-positive tumors (rs2981582/FGFR2, rs4415084/MRPS30, rs1219648/FGFR2, rs2981579/FGFR2, and rs11200014/FGFR2). Among our Chinese population, the risk of developing breast cancer increased by 90 % for those with a combination of 6 or more risk alleles, compared to patients with ≤3 risk alleles.


Subject(s)
Breast Neoplasms , Genetic Association Studies , Polymorphism, Single Nucleotide , Adult , Alleles , Breast Neoplasms/genetics , Breast Neoplasms/pathology , China , Female , Genetic Loci , Genetic Predisposition to Disease , Humans , Linkage Disequilibrium , Receptors, Estrogen/genetics , Receptors, Progesterone/genetics , Risk Factors
5.
Lett Appl Microbiol ; 53(3): 371-3, 2011 Sep.
Article in English | MEDLINE | ID: mdl-21679200

ABSTRACT

AIMS: To test a performance of the microbiological safety cabinets (MSCs) according to the type of MSCs in microbial laboratories. METHODS AND RESULTS: Tests were carried out to assess the performance of 31 MSCs in 14 different facilities, including six different biological test laboratories in six hospitals and eight different laboratories in three universities. The following tests were performed on the MSCs: the downflow test, intake velocity test, high-efficiency particulate air filter leak test and the airflow smoke pattern test. These performance tests were carried out in accordance with the standard procedures. Only 23% of Class II A1 (8), A2 (19) and unknown MSCs (4) passed these performance tests. The main reasons for the failure of MSCs were inappropriate intake velocity (65%), leakage in the HEPA filter sealing (50%), unbalanced airflow smoke pattern in the cabinets (39%) and inappropriate downflow (27%). CONCLUSIONS: This study showed that routine checks of MSCs are important to detect and strengthen the weak spots that frequently develop, as observed during the evaluation of the MSCs of various institutions. SIGNIFICANCE AND IMPACT OF THE STUDY: Routine evaluation and maintenance of MSCs are critical for optimizing performance.


Subject(s)
Air Microbiology , Laboratories/standards , Filtration , Hospitals , Humans , Republic of Korea , Safety , Universities
6.
Pharm Res ; 26(4): 794-801, 2009 Apr.
Article in English | MEDLINE | ID: mdl-18998201

ABSTRACT

PURPOSE: The purpose of this study is to examine the efficiency of sonoporation with minicircle DNA for the skin wound healing in diabetic mice. METHODS: Minicircle DNA containing the human VEGF(165) was constructed and tested in vitro. Diabetes was induced in 2-week old male C57BL/6J mice via streptozotocin (STZ) injection. 6 mm circular skin wounds were made on the mice back. After the subcutaneous injection of the minicircle DNA at the edge of the wound, the mice were exposed to the ultrasound irradiation for the sonoporation. Wound areas were analyzed until the day 12. Blood perfusion and angiogenesis were evaluated using a laser Doppler imaging and CD31 immunostaining, respectively. Re-epithelialization was assessed by histochemical analysis using hematoxylin and eosin staining. RESULTS: Accelerated wound closure was observed in the mice receiving sonoporation of minicircle-VEGF(165), which corresponds to the markedly increased skin blood perfusion and CD31 expression. Histological analysis revealed that the minicircle treated wound tissues showed fully restored normal architectures as compared with the non-treated diabetic controls with the markedly edematous and chaotic morphologies. CONCLUSIONS: Ultrasound mediated gene therapy with the minicircle-VEGF(165) is effective for the healing of the skin wound of the diabetic mice.


Subject(s)
DNA, Superhelical , Diabetes Mellitus, Experimental/therapy , Genetic Therapy/methods , Skin/physiopathology , Transfection/methods , Ultrasonics , Vascular Endothelial Growth Factor A/genetics , Wound Healing , Animals , CHO Cells , Cricetinae , Cricetulus , Diabetes Mellitus, Experimental/genetics , Diabetes Mellitus, Experimental/pathology , Diabetes Mellitus, Experimental/physiopathology , Humans , Laser-Doppler Flowmetry , Male , Mice , Mice, Inbred C57BL , Microbubbles , NIH 3T3 Cells , Neovascularization, Physiologic , Regional Blood Flow , Skin/blood supply , Skin/pathology , Time Factors , Vascular Endothelial Growth Factor A/biosynthesis
7.
Acta Radiol ; 49(4): 427-35, 2008 May.
Article in English | MEDLINE | ID: mdl-18415787

ABSTRACT

BACKGROUND: The presence and extent of osteolytic bone lesions in untreated patients with multiple myeloma are important factors in the staging of the disease, and the extent of bone lesions in multiple myeloma cases significantly influences decisions regarding therapy. Recently, fluorodeoxyglucose positron emission tomography (FDG-PET) and magnetic resonance imaging (MRI) have been used to detect bone marrow involvement in patients with multiple myeloma. PURPOSE: To compare the efficacy of FDG-PET and MRI for the detection of bone marrow infiltration into the spine in untreated patients with multiple myeloma. MATERIAL AND METHODS: Twenty-two patients with multiple myeloma underwent both FDG-PET and spine MRI. The examined spinal regions by MRI included 21 thoracic and lumbar spines, one lumbar spine, and 12 cervical spines. The following imaging sequences were performed: T1-weighted spin-echo MRI with and without fat suppression, and T2-weighted spin-echo MRI in the sagittal plane. In the patients with bone marrow abnormalities, an additional contrast-enhanced T1-weighted spin-echo MR image and a fat-suppressed T1-weighted spin-echo MR image were obtained. Patients were divided into three groups on the basis of the criteria defined by Durie and Salmon: stage I (n=9), stage II (n=3), and stage III (n=10). The number and location of lesions detected in both FGD-PET and MRI were recorded, and the lesions were compared using the McNemar test. Bone marrow biopsy results, the patient's clinical examinations, and other imaging findings (MRI, FDG-PET, etc.) were used as references. RESULTS: In stages I and II (37 lesions in 12 patients), FDG-PET and MRI detected lesions in 78% (29 of 37 lesions) and 86% (32 of 37 lesions), respectively. However, the difference between the abilities of FDG-PET and MRI to detect lesions was not statistically significant (P=0.317). In stage III (101 lesions in 10 patients), FDG-PET and MRI detected lesions in 80% (81 of 101 lesions) and 92% (93 of 101 lesions), respectively. The difference between the abilities of FDG-PET and MRI to detect lesions was statistically significant (P=0.038). CONCLUSION: MRI is superior to FDG-PET in detecting bone marrow involvement in the spine of patients with advanced multiple myeloma.


Subject(s)
Bone Marrow/pathology , Fluorodeoxyglucose F18 , Magnetic Resonance Imaging , Multiple Myeloma/diagnostic imaging , Multiple Myeloma/diagnosis , Positron-Emission Tomography , Radiopharmaceuticals , Spinal Neoplasms/diagnostic imaging , Spinal Neoplasms/diagnosis , Aged , Algorithms , Contrast Media , Female , Gadolinium DTPA , Humans , Image Interpretation, Computer-Assisted , Male , Middle Aged , Sensitivity and Specificity
8.
Nanotechnology ; 19(12): 125604, 2008 Mar 26.
Article in English | MEDLINE | ID: mdl-21817736

ABSTRACT

During pyrolysis of polyimide (PI) thin film, amorphous silicon oxide nanowires (SiO(x)NWs) were produced on a large scale through heat treatment of an Au nanoparticle/PI/Si thin film stack at 1000 °C. It was shown that carbonization of the PI film preceded the nucleation of the SiO(x)NWs. The formation of the SiO(x)NWs was sustained by the oxygen derived from carbonization of the polyimide thin film while Si was provided from the substrate. Au nanoparticles promoted the SiO(x)NW growth by inducing localized melting of the Si substrate and by catalyzing the nanowire growth.

9.
Hum Exp Toxicol ; 26(3): 203-11, 2007 Mar.
Article in English | MEDLINE | ID: mdl-17439923

ABSTRACT

We utilized a mice model of Parkinsonism: (1) to evaluate 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced neurotoxicity; and (2) to evaluate whether manganese (Mn) exposure can affect MPTP-induced neurotoxicity. A 2 x 3 experimental design (MPTP x+/- Mn) was as follows: SS, MPTP(-) x Mn(-); SLMn, MPTP(-) x low Mn(+); SHMn, MPTP(-) x high Mn(+); MpS, MPTP(+) x Mn(-); MpLMn, MPTP(+) x low Mn(+); MpHMn, MPTP(+) x high Mn(+). We administered MPTP (30 mg/kg per day) to male C57BL/6 mice intraperitoneally, once a day for 5 days. Subsequently, mice were treated with either 2 or 8 mg/kg of MnCl(2).4H(2)O intraperitoneally, once a day for 3 weeks. Blood and striatal Mn levels were elevated in the Mnexposed groups. The number of tyrosine hydroxylase (TH)-immunoreactive (ir) neurons in the substantia nigra pars compacta were decreased significantly in the MPTP-exposed groups. The densities of TH-ir axon terminals in caudate-putamen (CPU) were significantly decreased in the MPTP-treated groups. However, Mn treatment did not affect MPTP neurotoxicity. The densities of glial fibrillary acidic protein (GFAP)-ir astrocytes in the CPU or globus pallidus were significantly increased in the MPTP-treated groups. Concentrations of dopamine in the striatum were decreased significantly in the MPTP-exposed groups only, but Mn had no effect.


Subject(s)
MPTP Poisoning/chemically induced , Manganese/toxicity , 1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine , Animals , Corpus Striatum/drug effects , Corpus Striatum/metabolism , Disease Models, Animal , Dopamine/metabolism , Dopamine Agents , Drug Interactions , Glial Fibrillary Acidic Protein/metabolism , Male , Manganese/blood , Manganese/pharmacokinetics , Mice , Mice, Inbred C57BL , Neurotoxins , Tyrosine 3-Monooxygenase/metabolism
10.
Acta Radiol ; 48(2): 238-41, 2007 Mar.
Article in English | MEDLINE | ID: mdl-17354148

ABSTRACT

Skeletal muscle metastasis is a rare condition in renal cell carcinoma (RCC). We here present an extremely rare case of late recurrence in a patient with RCC who had multiple muscle metastases 19 years after radical nephrectomy. This case shows that a soft-tissue mass in a patient with a known history of RCC even after curative nephrectomy, particularly with hypervascularity, must be regarded as highly suspicious of skeletal muscle metastasis.


Subject(s)
Carcinoma, Renal Cell/secondary , Kidney Neoplasms/pathology , Muscle Neoplasms/secondary , Carcinoma, Renal Cell/diagnostic imaging , Humans , Kidney Neoplasms/surgery , Male , Middle Aged , Muscle Neoplasms/diagnostic imaging , Muscle, Skeletal , Nephrectomy , Tomography, Emission-Computed , Tomography, X-Ray Computed
11.
Bioresour Technol ; 98(1): 165-8, 2007 Jan.
Article in English | MEDLINE | ID: mdl-16387491

ABSTRACT

The molecular weight of exo-biopolymer obtained from a submerged culture of Cordyceps sinensis 16 consisted of a main unit and a subunit of 126 and 68 kDa, respectively. The optimal medium for the production of mycelia and exo-biopolymer was determined to be molasses containing 2% sucrose, 0.9% yeast extract, 0.3% K2HPO4, and 0.4% CaCl2. Using optimized medium, maximum productions of mycelia and exo-biopolymer in shake-flask culture were 54.0 g/L and 28.4 g/L, respectively. This study suggests that large-scale production of mycelia and exo-biopolymer by C. sinensis 16 is possible in submerged culture.


Subject(s)
Biopolymers/metabolism , Cordyceps/metabolism , Molasses , Mycelium/growth & development , Culture Media , Time Factors
12.
Neurosci Lett ; 403(1-2): 11-4, 2006 Jul 31.
Article in English | MEDLINE | ID: mdl-16687213

ABSTRACT

Recent reports of SCA2 and SCA3 patients who presented with levodopa responsive parkinsonism have generated considerable interest as they have implications for genetic testing. It is unclear whether ethnic race alone or founder effects within certain geographical region explain such an association. In this study, we conducted genetic analysis of SCA2, 3, 17 in an ethnic Chinese cohort with early onset and familial Parkinson's disease (PD) and healthy controls. A total of 191 subjects comprising of 91 PD and 100 healthy controls were examined. We identified one positive case of SCA2 in an early-onset sporadic PD patient who had CAG 36 repeats, yielding a prevalence of 2.2% in early-onset sporadic PD patients and less than 1.0% in our study PD population. The size of the repeats was lower than the expanded repeats (38-57) in SCA2 patients with ataxia in our population. All the children of the patient were physically normal even though some of them carried the repeat expansion of similar size. No cases and controls were positive for SCA3 and SCA17. We do not think routine screening of SCA2, SCA3 and SCA17 for all idiopathic PD patients is cost-effective in our ethnic Chinese population. However, SCA2 should be a differential diagnosis in young onset sporadic PD when genetic mutations of other known PD genes have been excluded.


Subject(s)
Nerve Tissue Proteins/genetics , Nuclear Proteins/genetics , Parkinson Disease/genetics , Repressor Proteins/genetics , TATA-Box Binding Protein/genetics , Adult , Aged , Aged, 80 and over , Asian People , Ataxin-3 , Ataxins , Base Sequence , Female , Humans , Male , Middle Aged , Molecular Sequence Data , Repetitive Sequences, Nucleic Acid
13.
J Colloid Interface Sci ; 287(2): 501-6, 2005 Jul 15.
Article in English | MEDLINE | ID: mdl-15925616

ABSTRACT

Nanoparticles with different morphology and composition were fabricated inside a polyimide (PI) matrix based on selectively oxidizing a layer of Fe(100-x)Pt(x) alloy metal film sandwiched between two PI precursor layers. Gamma-Fe2O3, Pt, and Fe3Pt nanoparticles were formed in a monolayer between two PI layers, depending on the alloy film composition and curing conditions. These particles were well-crystallized and sized between 4 and 10 nm. X-ray photoelectron spectroscopy confirmed that Fe in the film preferentially reacted with the organic matrix whereas Pt remained metallic throughout the curing process, which enabled fabrication of particles different morphology and composition. This process can be easily extended to other alloy films, which provides an opportunity to fabricate nanoparticles relatively easily with desired composition and morphology embedded in an inert organic matrix.

14.
Biotechnol Lett ; 27(2): 135-9, 2005 Jan.
Article in English | MEDLINE | ID: mdl-15703878

ABSTRACT

Conidia of Beauveria bassiana CS-1, which have the potential for the control of the diamondback moth (Plutella xylostella), were produced by solid-state fermentation (SSF) using a packed-bed bioreactor with rice straw and wheat bran. As the packing density and the bed height were increased, the production of conidia decreased. In a packed-bed bioreactor under no aeration and no addition of polypropylene (PP) foam (control), the total average of conidia was 4.9 x 10(8) g-1. The production of conidia was affected more by the addition of PP foam as an inert support than forced aeration and was approx. 23 times higher than that of the control. The total average of conidia produced by B. bassiana was 1.1-1.2 x 10(10) g-1 .


Subject(s)
Ascomycota/metabolism , Bioreactors , Biotechnology/methods , Moths/physiology , Air , Animals , Ascomycota/physiology , Biotechnology/instrumentation , Fermentation , Moths/microbiology , Oryza , Pest Control, Biological , Polypropylenes
15.
Ann Acad Med Singap ; 34(1): 73-7, 2005 Jan.
Article in English | MEDLINE | ID: mdl-15726222

ABSTRACT

INTRODUCTION: Spinal muscular atrophy (SMA) is an autosomal recessive neuromuscular disorder characterised by degeneration of spinal cord anterior horn cells, leading to muscular atrophy. It is the second most frequent autosomal recessive disease among Caucasian populations with a prevalence of between 1 in 6000 and 1 in 10,000 live births, and a carrier frequency of about 1 in 50. The International SMA Consortium classification defines several types of SMA depending on the age of onset and clinical severity. In the past, the diagnosis of SMA was confirmed by muscle biopsy and, sometimes, electromyography. In 1990, SMA was linked to the 5q13 region of chromosome 5. In 1995, it was found that >95% of patients with SMA have homozygous deletions of exons 7 and 8 of the survival motor neurone 1 (SMN1) gene, one of the candidate genes identified within 5q13. The purpose of our study was to determine the frequency of SMN1 deletions in patients with known SMA and the impact of this on the diagnosis of SMA. MATERIALS AND METHODS: Molecular analysis was performed on stored DNA and case notes were reviewed retrospectively. RESULTS: Twenty-two (91.7%) out of 24 patients with all types of SMA were homozygously deleted for exons 7 and/or 8 of SMN1. We also report our experience with prenatal diagnosis of SMA. CONCLUSIONS: Molecular studies can replace conventional investigations for SMA and have made the option of prenatal diagnosis possible for couples at risk.


Subject(s)
Cyclic AMP Response Element-Binding Protein/genetics , DNA/analysis , Gene Deletion , Nerve Tissue Proteins/genetics , RNA-Binding Proteins/genetics , Spinal Muscular Atrophies of Childhood/genetics , Adult , Age of Onset , Biopsy , Child, Preschool , Electromyography , Exons/genetics , Female , Follow-Up Studies , Homozygote , Humans , Infant , Infant, Newborn , Male , Muscle, Skeletal/pathology , Muscle, Skeletal/physiopathology , Polymerase Chain Reaction , Pregnancy , Retrospective Studies , SMN Complex Proteins , Singapore/epidemiology , Spinal Muscular Atrophies of Childhood/diagnosis , Spinal Muscular Atrophies of Childhood/epidemiology , Survival Rate , Survival of Motor Neuron 1 Protein
16.
J Colloid Interface Sci ; 273(2): 517-22, 2004 May 15.
Article in English | MEDLINE | ID: mdl-15082389

ABSTRACT

A monolayer of gamma-Fe(2)O(3) nanoparticles embedded in a polyimide (PI) matrix was fabricated by oxidizing an Fe metal film between two PI precursor layers. There was a critical Fe thickness ( approximately 7 nm) above which a continuous layer of gamma-Fe(2)O(3) film was formed in the PI film. Below the critical Fe thickness, the oxide film broke up into fine particles whose size was approximately 8 nm with narrow size distribution. It was further shown that these nanoparticles could have metallic cores, surrounded by an oxide layer. This method offers a unique way of covering a large surface area with fine magnetic oxide nanoparticles for potential application in high-density data-storage media.

18.
Acta Physiol Scand ; 179(2): 167-72, 2003 Oct.
Article in English | MEDLINE | ID: mdl-14510780

ABSTRACT

AIM: Effects of prolonged habitual cold-water immersion on fibre size and capillarity in vastus lateralis muscle were studied in human beings. The hypothesis tested in the present study was that cold acclimatized human skeletal muscle would have reduced muscle fibre size and higher capillarity, favouring the idea of efficacy of recruitment under cold environment. METHODS: Ten women breath-hold divers (BHDs) and 10 active women (controls CONs) participated in this study. Muscle biopsy was obtained from vastus lateralis and determined fibre type composition and capillary density. RESULTS: A major finding was that all BHDs revealed a markedly smaller cross-sectional area (CSA) in all fibre types than the CONs, or even than any other morphological data reported in previous investigations. Furthermore, mean CSA of type II fibre (range 1205-2766 microm2) was much smaller than type I fibre (2343-4327 microm2). The number of capillaries per fibre in different fibre types in the BHDs was higher than in the CONs (P < 0.001), and diffusional area was smaller in type II fibres than in type I fibres (P < 0.001). The BHDs and the CONs have similarity in the percentage of type I fibres, but type II fibre was predominant in both groups. Interestingly the proportion of type IIx fibre in the BHDs was higher (31%) than in the CONs (22%). No significant difference was found in the thigh circumference between the groups. CONCLUSION: The present study demonstrates that prolonged habitual cold-water immersion may induce a decrease in fibre size and an increase in capillarity in human skeletal muscle.


Subject(s)
Diving/physiology , Muscle Fibers, Skeletal/physiology , Muscle, Skeletal/anatomy & histology , Adipose Tissue/physiology , Adult , Aged , Anaerobiosis/physiology , Body Weight/physiology , Capillaries/physiology , Cold Temperature/adverse effects , Ergometry/methods , Female , Humans , Immersion , Middle Aged , Muscle, Skeletal/blood supply , Respiration , Thigh/anatomy & histology , Water
19.
Clin Genet ; 62(6): 478-81, 2002 Dec.
Article in English | MEDLINE | ID: mdl-12485197

ABSTRACT

We report the prevalence and ethnic differences of autosomal-dominant cerebellar ataxia (ADCA) in Singapore. Amongst 204 patients with ataxia who underwent genetic testing for dentatorubral-pallidoluysian atrophy (DRPLA) and for spinocerebellar ataxias (SCA) 1, 2, 3, 6, 7, 8, 10 and 12, 58 (28.4%) patients from 36 families tested positive. SCA 3 was identified in 31 (53.4%) patients from 15 families, SCA 2 in 17 (29.3%) patients from 12 families and SCA 1 in four (6.9%) patients from four families. Other SCA subtypes were rare. SCA 2 was the only subtype identified amongst ethnic Malay and ethnic Indian families. The estimated prevalence of ADCA in Singaporean families was at least 1 : 27,000. Based on the history and ancestry of Singaporeans, our study supported a founder effect for specific SCA subtypes and the association of ethnicity-specific SCA subtypes. Our findings suggest that SCA 2 is relatively common amongst the Malay race and that priority testing for SCA 3 and SCA 2 for ethnic Chinese, and SCA 2 for ethnic Malay, may be cost effective and relevant for the region.


Subject(s)
Cerebellar Ataxia/genetics , Ethnicity/genetics , Cerebellar Ataxia/epidemiology , Cerebellar Ataxia/ethnology , China/ethnology , Family Health , Founder Effect , Genes, Dominant , Humans , Malaysia/ethnology , Prevalence , Singapore/epidemiology
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