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Wang JS, Yang CF, Wong MK. Effect of strenuous arm crank exercise on platelet function in patients with spinal cord injury. Arch Phys Med Rehabil 2002; 83:210-6. [PMID: 11833024 DOI: 10.1053/apmr.2002.28033] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
OBJECTIVE To investigate the effects of arm crank exercise on various platelet functions and prostacyclin in individuals with spinal cord injury (SCI). DESIGN Case-control study. SETTING Research project at a hospital-based exercise physiology laboratory. PARTICIPANTS Seven men (with lesions at levels T11, n = 1; T12, n = 2; L1, n = 2; L2, n = 2) and 3 women (T12, n = 1; L1, n = 2) in the SCI group had SCI for at least 6 weeks. Ten age- and gender-matched healthy people who had not engaged in any regular physical activity for at least 1 year were selected as the control group. INTERVENTION All subjects exercised strenuously by using an arm crank engometer. MAIN OUTCOME MEASURE Platelet adhesiveness on fibrinogen-coated surface and epinephrine-induced aggregation in vitro, plasma soluble P-selectin (sP-selectin), and urinary 6-keto-prostaglandin F(1alpha) (6-keto PGF(1alpha)) levels. RESULTS The SCI group had higher platelet adhesiveness and aggregability and plasma sP-selectin level, but lower urinary 6-keto PGF(1alpha) level than the control group. Platelet adhesiveness and aggregability were enhanced by strenuous arm exercise in all subjects, but only in the SCI group was sP-selectin level increased by exercise. Strenuous exercise raised the levels of 6-keto PGF(1alpha) in control group subjects, but not in subjects with SCI. CONCLUSIONS Individuals with SCI had more extensive basal and exercise-induced platelet activation and sP-selectin release than people without SCI. Moreover, strenuous arm exercise, which enhanced the release of prostacyclin in healthy subjects, failed to do so in those with SCI.
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Wong MK, Yu CW, Yuen WH, Yang D. Synthesis of alpha-keto esters and amides via oxidative cleavage of cyanoketophosphoranes by dimethyldioxirane. J Org Chem 2002; 66:3606-9. [PMID: 11348154 DOI: 10.1021/jo0015974] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Wong MK, Ching LK, Lim SL, Lo NN. Osteoporotic hip fractures in Singapore--costs and patient's outcome. ANNALS OF THE ACADEMY OF MEDICINE, SINGAPORE 2002; 31:3-7. [PMID: 11885492] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/24/2023]
Abstract
INTRODUCTION Little data are available on costs and outcome associated with osteoporotic hip fractures in Singapore. MATERIALS AND METHODS A retrospective study was carried out on 280 consecutive hip fractures in patients older than 60 years admitted over a 3-year period. RESULTS The mean age of patients was 80 years. Sixty-eight per cent were female and 58% were intertrochanteric fractures. Two hundred and sixty-four patients (95%) were operated upon. The mean total hospitalisation period was 17 days. Seventy-six per cent were staying in their own homes prior to the hip fracture while 22% were admitted from nursing homes. After surgery, 63% of patients returned to their homes while 26% needed nursing home care. The index admission mortality rate was 5.7%. Mortality was 26% at 1 year. Of those alive at 1 year, ambulatory status was: 28% were walking without aids, 39% were walking with aids, 24% were wheelchair bound and 9% were bedridden. Poor ambulatory function at discharge was related to increased mortality at 1 year. The average cost incurred was S$7367. The average government subsidy amounted to 82%. Ninety-one per cent of patients were warded in subsidized beds. Breakdown of cost was as follows: hospital stay, 42.6%; surgery, 36.5%; ward treatment, fee 9%; laboratory and X-ray investigations, 4.4%; implant costs, 3.5%; drugs, 1.6% and rehabilitation, 1.1%. Multivariate analysis showed that the cost is significantly related to days spent awaiting surgery, preoperative sepsis, operative complications and cerebrovascular accidents. Young age, good American Society of Anesthetists (ASA) status and endoprosthesis replacement were factors that allowed for early ambulation and lower costs. CONCLUSION The mortality rates and functional outcome are not very different from published studies in the West. More of our patients returned to their own homes after hospitalisation. Early surgery, close involvement of the medical social worker and intensive physiotherapy or provision of outpatient therapy facilities may help cut cost of treatment.
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Yuen KY, Woo PC, Teng JL, Leung KW, Wong MK, Lau SK. Laribacter hongkongensis gen. nov., sp. nov., a novel gram-negative bacterium isolated from a cirrhotic patient with bacteremia and empyema. J Clin Microbiol 2001; 39:4227-32. [PMID: 11724825 PMCID: PMC88529 DOI: 10.1128/jcm.39.12.4227-4232.2001] [Citation(s) in RCA: 109] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
A bacterium was isolated from the blood and empyema of a cirrhotic patient. The cells were facultatively anaerobic, nonsporulating, gram-negative, seagull shaped or spiral rods. The bacterium grows on sheep blood agar as nonhemolytic, gray colonies 1 mm in diameter after 24 h of incubation at 37 degrees C in ambient air. Growth also occurs on MacConkey agar and at 25 and 42 degrees C but not at 4, 44, and 50 degrees C. The bacterium can grow in 1 or 2% but not 3, 4, or 5% NaCl. No enhancement of growth is observed with 5% CO(2). The organism is aflagellated and nonmotile at both 25 and 37 degrees C. It is oxidase, catalase, urease, and arginine dihydrolase positive, and it reduces nitrate. It does not ferment, oxidize, or assimilate any sugar tested. 16S rRNA gene sequencing showed that there are 91 base differences (6.2%), 112 base differences (7.7%), and 116 base differences (8.2%) between the bacterium and Microvirgula aerodenitrificans, Vogesella indigofera, and Chromobacterium species, respectively. The G+C content (mean and standard deviation) is 68.0% +/- 2.43%, and the genomic size is about 3 Mb. Based on phylogenetic affiliation, the bacterium belongs to the Neisseriaceae family of the beta-subclass of Proteobacteria. For these reasons, a new genus and species, Laribacter hongkongensis gen. nov., sp. nov., is proposed, for which HKU1 is the type strain. Further studies should be performed to ascertain the potential of this bacterium to become an emerging pathogen.
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Aberg JA, Wong MK, Flamm R, Notario GF, Jacobson MA. Presence of macrolide resistance in respiratory flora of HIV-Infected patients receiving either clarithromycin or azithromycin for Mycobacterium avium complex prophylaxis. HIV CLINICAL TRIALS 2001; 2:453-9. [PMID: 11742432 DOI: 10.1310/13gy-1lby-355n-89hf] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Clarithromycin 500 mg po bid or azithromycin 1200 mg po weekly is recommended as first line prophylaxis for Mycobacterium avium complex (MAC) in patients with HIV infection whose CD4 counts are <50 cells/microL. HIV-infected patients with CD4+ T-cell counts <200 cells/microL were randomized to receive either clarithromycin 500 mg po bid or azithromycin 1200 mg po weekly for 12 weeks. Nasopharyngeal swabs for Streptococcus pneumoniae and Haemophilus influenzae plus an anterior nare culture for Staphylococcus aureus were obtained at pretreatment, at 6 weeks, and at 12 weeks. A throat culture for oral flora was obtained for susceptibility testing against erythromycin. Minimum inhibitory concentrations (MICs) for clarithromycin and azithromycin were performed on all S. pneumoniae, H. influenzae, and S. aureus isolates. The study was terminated after respiratory flora, from all participants, revealed macrolide resistance. Because results of recent randomized trials indicate minimal efficacy of continuing MAC prophylaxis in patients who respond to potent combination antiretroviral therapy, the observed high incidence of macrolide-resistant bacterial colonization of the respiratory tract in this trial supports the discontinuation of macrolide prophylaxis in all AIDS patients whose CD4 counts have risen above 100 cells/microL.
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McMahon GA, Petitclerc E, Stefansson S, Smith E, Wong MK, Westrick RJ, Ginsburg D, Brooks PC, Lawrence DA. Plasminogen activator inhibitor-1 regulates tumor growth and angiogenesis. J Biol Chem 2001; 276:33964-8. [PMID: 11441025 DOI: 10.1074/jbc.m105980200] [Citation(s) in RCA: 190] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Elevated expression of plasminogen activator inhibitor-1 (PAI-1) in tumors is associated with a poor prognosis in many cancers. Reduced tumor growth and angiogenesis have also been reported in mice deficient in PAI-1. These results suggest that PAI-1 may be required for efficient angiogenesis and tumor growth. In the present study, we demonstrate that PAI-1 can both enhance and inhibit the growth of M21 human melanoma tumors in nude mice and that this appears to be due to PAI-1 regulation of angiogenesis. Quantitative analysis of angiogenesis in a Matrigel implant assay indicated that in PAI-1 null mice angiogenesis was reduced approximately 60% compared with wild-type mice, while in mice overexpressing PAI-1, angiogenesis was increased nearly 3-fold. Furthermore, addition of PAI-1 to implants in wild-type mice enhanced angiogenesis up to 3-fold at low concentrations but inhibited angiogenesis nearly completely at high concentrations. Together, these data demonstrate that PAI-1 is a potent regulator of angiogenesis and hence of tumor growth and suggest that understanding the mechanism of this activity may lead to the development of important new therapeutic agents for controlling pathologic angiogenesis.
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Wang JS, Lan C, Wong MK. Tai Chi Chuan training to enhance microcirculatory function in healthy elderly men. Arch Phys Med Rehabil 2001; 82:1176-80. [PMID: 11552187 DOI: 10.1053/apmr.2001.24305] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
OBJECTIVE To evaluate cutaneous microcirculatory function in geriatric Tai Chi Chuan (TCC) practitioners. DESIGN Case-control study. SETTING Community setting. PARTICIPANTS Ten elderly male TCC practitioners (mean age, 69.9 +/- 1.5 yr) and 10 sedentary men with matched age and body size (mean age, 67.0 +/- 1.0 yr). INTERVENTION The TCC group had practiced TCC for 11.2 +/- 3.4 years (mean +/- standard error of the mean), with an exercise frequency of 5.1 +/- 1.8 times weekly. Each session included 20 minutes of warm-up, 24 minutes of TCC practice, and 10 minutes of cool down. MAIN OUTCOME MEASURES A graded exercise test with gas analysis was conducted on a bicycle ergometer for each subject. Skin blood flow (SkBF), cutaneous vascular conductance, and skin temperature were measured at rest and during exercise testing. Plasma nitric oxide metabolite was analyzed before and immediately after exercise. RESULTS The TCC group had a 34% higher VO(2)peak than the control group; it also had a higher SkBF, cutaneous vascular conductance, and skin temperature than the control group at rest and during exercise; and it also had a higher level of plasma nitric oxide metabolite than the sedentary group at rest and after exercise. CONCLUSION Older TCC practitioners had higher cutaneous microcirculatory function during exercise than did their sedentary counterparts. Moreover, this change may be partially mediated by enhancement of nitric oxide release.
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Wong PY, Wang YC, Chu NK, Tang FT, Wong MK. Body weight, serum uric acid and lipid profile one year after spinal cord injury. CHANG GUNG MEDICAL JOURNAL 2001; 24:569-75. [PMID: 11725627] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/22/2023]
Abstract
BACKGROUND Survey of the serum lipoprotein profile, uric acid levels and body weight in Chinese patients with spinal cord injury (SCI) one year after injury, and to report the data of patients with SCI at different levels. METHODS Seventy-seven Chinese patients with SCI categorized into cervical SCI, thoracic SCI, and lumbar SCI groups were enrolled in the study. The serum uric acid and lipoprotein profiles of these patients were evaluated one year after injury. All of the data in those different groups of SCI patients were compared with normal levels. Body weight before and after injury were also evaluated. RESULTS Serum uric acid was within normal limits in all three SCI groups. A similar lower in serum high density lipoprotein cholesterol (HDL-C) level was observed in all three groups of SCI patients. Higher serum levels were observed in total cholesterol (TC) in the lumbar SCI group, triglyceride and very low density lipoprotein cholesterol in the thoracic and lumbar SCI group, and TC/HDL-C ratio in all three SCI groups. Decrease of body weight were noted in cervical and thoracic SCI patients. CONCLUSION Further long-term follow up was necessary to determine the serum lipid and body weight change in patients with SCI at different levels.
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Wong MK, Ho LM, Zheng YS, Ho CY, Yang D. Asymmetric epoxidation of olefins catalyzed by chiral iminium salts generated in situ from amines and aldehydes. Org Lett 2001; 3:2587-90. [PMID: 11483067 DOI: 10.1021/ol016260i] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
[reaction: see text] A new approach for catalytic asymmetric epoxidation of olefins was developed that utilized chiral iminium salts, generated in situ from chiral amines and aldehydes, as catalysts. Epoxidation reactions can be conducted with 20 mol % of amines and aldehydes. The enantioselectivity of epoxides can be up to 65%. This modular approach obviates the difficulties inherent in the preparation and isolation of unstable exocyclic iminium salts.
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Yang D, Jiao GS, Yip YC, Lai TH, Wong MK. Kinetic resolution of acyclic secondary allylic silyl ethers catalyzed by chiral ketones. J Org Chem 2001; 66:4619-24. [PMID: 11421782 DOI: 10.1021/jo010068c] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Kinetic resolution of acyclic secondary allylic silyl ethers by chiral dioxiranes generated in situ from chiral ketones (R)-1 and (R)-2 and Oxone was investigated. An efficient and catalytic method has been developed for kinetic resolution of those substrates with a CCl(3), tert-butyl, or CF(3) group at the alpha-position. In particular, high selectivities (S up to 100) were observed for kinetic resolutions of racemic alpha-trichloromethyl allylic silyl ethers 7 and 9-15 catalyzed by ketones (R)-2. Both the recovered substrates and the resulting epoxides were obtained in high enantiomeric excess. On the basis of steric and electrostatic interactions between the chiral dioxiranes and the racemic substrates, a model was proposed to rationalize the enantioselectivities and diastereoselectivities in the chiral ketone-catalyzed kinetic resolution process.
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Yuen JS, Yung SW, Wong MK. Open reduction and temporary rigid internal fixation of Lisfranc fracture-dislocations. Singapore Med J 2001; 42:255-8. [PMID: 11547962] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/21/2023]
Abstract
AIM To review the results of open reduction and temporary rigid screw fixation of Lisfranc fracture-dislocations performed in Singapore General Hospital (SGH) from 1996 to 1998. METHODS A retrospective review of II cases of Lisfranc injuries treated with temporary rigid internal screw fixation with a minimum follow up of six months was carried out. Radiological assessment was made at follow up to ascertain the anatomical reduction achieved and complications such as post-traumatic arthritis. In addition, the patients were evaluated with a functional assessment with relation to pain, interference to usual activities and the time to resumption of work. RESULTS Anatomical reduction was achieved in all cases. None of the cases showed loss of reduction at follow up after the temporary implants were removed. No longitudinal arch collapse or other deformities were seen. All the patients had good or excellent functional outcomes. CONCLUSIONS Results of treatment of Lisfranc injuries are related to anatomical correction. Temporary screw fixation allows rigid internal fixation with stability to allow anatomical correction. Screws also maintain their stability longer, allowing ligamentous injuries the longer period necessary for healing. In conclusion, temporary rigid screw fixation of Lisfranc fracture maintains anatomical reduction and gives excellent functional outcomes for the patients.
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Stefansson S, Petitclerc E, Wong MK, McMahon GA, Brooks PC, Lawrence DA. Inhibition of angiogenesis in vivo by plasminogen activator inhibitor-1. J Biol Chem 2001; 276:8135-41. [PMID: 11083866 DOI: 10.1074/jbc.m007609200] [Citation(s) in RCA: 131] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The process of angiogenesis is important in both normal and pathologic physiology. However, the mechanisms whereby factors such as basic fibroblast growth factor promote the formation of new blood vessels are not known. In the present study, we demonstrate that exogenously added plasminogen activator inhibitor-1 (PAI-1) at therapeutic concentrations is a potent inhibitor of basic fibroblast growth factor-induced angiogenesis in the chicken chorioallantoic membrane. By using specific PAI-1 mutants with either their vitronectin binding or proteinase inhibitor activities ablated, we show that the inhibition of angiogenesis appears to occur via two distinct but apparently overlapping pathways. The first is dependent on PAI-1 inhibition of proteinase activity, most likely chicken plasmin, while the second is independent of PAI-1's anti-proteinase activity and instead appears to act through PAI-1 binding to vitronectin. Together, these data suggest that PAI-1 may be an important factor regulating angiogenesis in vivo.
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Abstract
OBJECTIVE To investigate the sonographic features of plantar fasciitis (PF). METHODS High-resolution ultrasound was used to measure the thickness and echogenicity of the proximal plantar fascia and associated heel pad thickness for 102 consecutive patients with PF (unilateral: 81, bilateral: 21) and 33 control subjects. RESULTS The mean thickness of the plantar fascia was greater on the symptomatic side for patients with bilateral and unilateral PF than on the asymptomatic side for patients with unilateral PF, and also control subjects (5.47+/-1.09, 5.61+/-1.19, 3.83+/-0.72, 3.19+/-0.43 mm, respectively, p<0.001). A substantial difference in thickness between the asymptomatic side of patients with unilateral PF and control subjects was also noted (p=0.001). The heel pad thickness was not show different between control subjects and patients with PF. The incidence of hypoechoic fascia was 68.3% (84/123). Other findings among the patients from our test group included intratendinous calcification (two cases), the presence of perifascial fluid (one case), atrophic heel pads (one case), and the partial rupture of plantar fascia (one case). CONCLUSION Increased thickness and hypoechoic plantar fascia are consistent sonographic findings in patients exhibiting PF. These objective measurements can provide sufficient information for the physician to confirm an initial diagnosis of PF and assess individual treatment regimens.
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Midha R, Shoichet MS, Dalton PD, Cao X, Munro CA, Noble J, Wong MK. Tissue engineered alternatives to nerve transplantation for repair of peripheral nervous system injuries. Transplant Proc 2001; 33:612-5. [PMID: 11266983 DOI: 10.1016/s0041-1345(00)02167-9] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Huang X, Wong MK, Zhao Q, Zhu Z, Wang KZ, Huang N, Ye C, Gorelik E, Li M. Soluble recombinant endostatin purified from Escherichia coli: antiangiogenic activity and antitumor effect. Cancer Res 2001; 61:478-81. [PMID: 11212235] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
Abstract
Endostatin is a potent and specific antiangiogenic protein capable of inhibiting the growth of murine and xenotransplanted human tumors. Thus far, however, recombinant endostatin prepared from Escherichia coli is insoluble after purification and therefore inappropriate for clinical settings. A soluble form of endostatin is available from a yeast system with relatively low yield and high cost, which has made it difficult to produce endostatin in quantities sufficient for extensive clinical evaluation. In this study, we developed a protocol to generate soluble recombinant murine endostatin from E. coli at a yield of 150 mg/liter-culture and 99% purity. The in vivo antiangiogenic and antitumor activities of the soluble recombinant endostatin are equally as potent as those of the previously published insoluble form. A similar protocol may be used to produce soluble human endostatin.
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Chen CL, Chen HC, Wong MK, Tang FT, Chen RS. Temporal stride and force analysis of cane-assisted gait in people with hemiplegic stroke. Arch Phys Med Rehabil 2001; 82:43-8. [PMID: 11239285 DOI: 10.1053/apmr.2001.18060] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
OBJECTIVE To understand the underlying biomechanics of temporal stride and force in people with hemiplegic stroke during cane-assisted walking. DESIGN Three forceplates, 6 cameras, and an instrumented cane were integrated to analyze the cane-assisted gait of people with hemiplegic stroke. Temporal-stride parameters, and peak vertical, anterior (propulsive), posterior (braking), and lateral shear forces, as well as propulsive-breaking impulses were analyzed. SETTING Chang Gung Memorial Hospital, Medical Center, Taiwan. PARTICIPANTS Twenty people with hemiplegic stroke. MAIN OUTCOME MEASURES Temporal-stride and force parameters. RESULTS All patients walked at a relatively slow speed, ranging from 4.2 to 35.8cm/s. The triple and double support occupied most of the gait cycle (GC), whereas the single support occupied only 10% of GC. The applied vertical, propulsive, braking, and lateral shear forces on either foot and the cane were 89.7% to 97.6%, 2.2% to 4.8%, 2.9% to 3.9%, and 5.5% to 6.7% body weight (BW), respectively. Patients applied less than 25% BW of peak vertical forces on the cane. They applied greater peak propulsive forces and impulses on the sound foot, while applying greater peak braking forces and impulses on the affected foot and cane. CONCLUSIONS The cane provided support and a braking function for people with hemiplegic stroke. People with stroke walking with cane assistance rely mostly on the sound limb for propulsion, while using the affected limb and cane for braking. Data provided could be useful in assessing the nature of cane assistance and in planning therapeutic strategies for people with stroke.
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Wu CY, Wong MK, Lin KC, Chen HC. Effects of task goal and personal preference on seated reaching kinematics after stroke. Stroke 2001; 32:70-6. [PMID: 11136917 DOI: 10.1161/01.str.32.1.70] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND AND PURPOSE Current theories of motor control in rehabilitation focus on how the nervous system responds to many types of external and internal constraints to execute motor behavior to accomplish a task. However, the dynamic interplay between these 2 constraints remains unclear. This study examined the impact of some aspects of internal and external constraints on motor performance in persons with stroke. METHODS Twenty-seven persons with stroke used the uninvolved arms to perform an upper-extremity reaching task under 4 experimental conditions, formed by the crossing of functional goals and personal preferences. For the higher level of a functional goal, subjects took a drink from a can of beverage. For the lower level of a functional goal, subjects brought the can to the mouth without drinking. The level of personal preferences was determined, by interview, by the degree of predilection for particular beverages. RESULTS Significant and large effects of functional goals and personal preference were found in the variables of movement time and reaction time. However, the data trend of the 4 testing conditions varied according to presence of visuospatial neglect and side of lesion. CONCLUSIONS Offering choices for the treatment activities and incorporating functional goals to therapeutic tasks might enhance response rate or movement efficiency, depending on the side of the lesion and presence of visuospatial neglect. The findings suggest that the consideration of the neglect phenomenon is a necessity when rehabilitative treatment planning incorporates constraint factors.
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Brown CK, Modzelewski RA, Johnson CS, Wong MK. A novel approach for the identification of unique tumor vasculature binding peptides using an E. coli peptide display library. Ann Surg Oncol 2000; 7:743-9. [PMID: 11129422 DOI: 10.1007/s10434-000-0743-0] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND Tumor neovascularization is necessary for continued tumor growth and metastasis. During the process of endothelial cell (EC) recruitment and tumor infiltration, specific molecular markers unique for this interaction are expressed on the EC surface. Targeting these molecular markers would, in effect, allow for specific tumor targeting. Tripeptide sequence motifs have previously been reported that will bind to angiogenic tumor ECs. These sequences were identified from in vivo phage peptide display libraries. The purpose of this study was to use a more simplified bacterial peptide display library in an in vitro system to seek out peptide motifs with unique binding to tumor microvasculature. METHODS FliTrx is a bacterial peptide display library containing the entire repertoire of possible random dodecapeptides expressed on the flagella tip of E. coli. Two EC populations were used for the screening process, Matrigel invading cells (MAGIC) and tumor-derived endothelial cells (TDEC). MAGIC are obtained from ECs that infiltrate a subcutaneous fibroblast growth factor-containing Matrigel deposit, and TDEC are ECs selectively obtained from tumor vasculature. FliTrx cells were incubated with MAGIC at 4 degrees C to remove any potential clones displaying peptides that will bind to nonspecific EC surface targets. The non-binding cells were then incubated with TDEC, allowing for clones displaying potential binding peptides to bind tumor specific targets on TDECs. The bacterial population was then expanded and this "panning" process was carried out a total of five times. Peptide insert sequences from 100 bacterial colonies were analyzed for potential repetitive peptide motifs. RESULTS Recurring peptide sequences were detected that were 3-mers (13 sequences) and 4-mers (4 sequences). Of the 3-mers, four repeated 3 times, whereas none of the 4-mers repeated more than twice. All of the repeated sequences were basic in charge, and arginine was the most commonly seen amino acid. A tripeptide basic-basic-nonpolar amino acid arrangement was the most prevalent charge sequence in all repetitive motifs (17 repeat sequences). Two test peptides showed TDEC binding specificity, and both conformed to the basic-basic-nonpolar motif. CONCLUSIONS We report peptide sequences derived from panning an in vitro system designed to detect tumor-EC specific markers. These putative motifs may serve as molecular determinants for a novel therapeutic modality aimed at specifically targeting tumors through tumor angiogenic vessels.
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Tsai WC, Wang CL, Tang FT, Hsu TC, Hsu KH, Wong MK. Treatment of proximal plantar fasciitis with ultrasound-guided steroid injection. Arch Phys Med Rehabil 2000; 81:1416-21. [PMID: 11030509 DOI: 10.1053/apmr.2000.9175] [Citation(s) in RCA: 77] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
OBJECTIVE To investigate the efficacy of ultrasound-guided steroid injection for the treatment of proximal plantar fasciitis and to evaluate mechanical properties of the heel pad after steroid injection. DESIGN Proximal plantar fascia and heel pad were assessed with a 10-MHz linear array ultrasound transducer. Pain intensity was quantified with a tenderness threshold (TT) and visual analog scale (VAS). The transducer was incorporated into a specially designed device to measure mechanical properties of the heel pad. Evaluations were performed before injection and at 2 weeks and 3 months after injection. SETTING An outpatient clinic of a tertiary care center. PATIENTS Fourteen consecutive patients with unilateral proximal plantar fasciitis. INTERVENTION Ultrasound-guided injection of 7 mg betamethasone and 0.5 mL of 1% lidocaine into the inflamed proximal plantar fascia. MAIN OUTCOME MEASURES VAS, TT, heel pad and plantar fascia thickness, and echogenicity of the proximal plantar fascia on sonogram were assessed. Mechanical properties included unloaded heel pad thickness, compressibility index, and energy dissipation ratio. RESULTS Both VAS score +/- standard deviation (SD; 5.43 +/- 2.03, 1.39 +/- 2.19, 0.57 +/- 1.40 at the 3 measurements, respectively) and TT +/- SD (5.05 +/- 1.42, 9.34 +/- 1.84, 9.93 +/- 1.98 kg/cm2 at the 3 measurements, respectively) improved significantly (p < .001) after steroid injection. The mean thickness of the plantar fascia was greater in the symptomatic side than in the asymptomatic side before treatment (0.58 +/- 0.13 cm vs 0.40 +/- 0.11 cm, p < .001). The thickness had decreased significantly 3 months after injection (0.46 +/- 0.12 cm at 2 weeks, 0.42 +/- 0.10 cm at 3 months, p < .001). The hypoechogenicity at the proximal plantar fascia disappeared after steroid injection (p < .001). Mechanical properties of the heel pad did not change 3 months after steroid injection (p > .05). CONCLUSION Ultrasound offers an objective measurement of the therapeutic effect on proximal plantar fasciitis. Accurate steroid injection under ultrasound guidance can effectively treat proximal plantar fasciitis without significant deterioration of the mechanical properties of the heel pads.
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Wexler EJ, Gravallese EM, Czerniak PM, Devenny JJ, Longtine J, Wong MK, Slee AM, Kerr JS. Tumor biology: use of tiled images in conjunction with measurements of cellular proliferation and death in response to drug treatments. Clin Cancer Res 2000; 6:3361-70. [PMID: 10955824] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/17/2023]
Abstract
Tumor growth is dependent on the balance between cell proliferation and cell death, and these events occur heterogenously within an individual tumor. We present a methodology that provides integrative information about cell kinetics, cell death, and cell growth within individual tumors in animals treated with cytotoxic chemotherapeutic agents. Using HCT-116 and NCI-H460 cells, human colonic adenocarcinoma and non-small cell lung cells, respectively, traditional xenograft studies were performed. The tumor-bearing animals were treated with cyclophosphamide (Cytoxan), gemcitabine (Gemzar), or mitomycin C, and extensive analysis of the tumors was studied. Cell kinetics were evaluated by measuring the apoptotic and proliferation indices. The ability to image an entire tumor section using "tiling" by creating a large montage from many high-resolution images makes it possible to identify regional differences within areas of tumor and to demonstrate differences in these tumor regions after treatment with selected chemotherapeutic agents. Two specific areas within tumors have been identified: (a) areas of viable cells within the cell cycle, determined by bromodeoxyuridine and/or morphological characteristics determined by hematoxylin staining; and (b) areas of necrosis determined by the absence of bromodeoxyuridine and proliferating cell nuclear antigen-labeled cells coupled with morphological changes. By standardizing the tumor size to 100 mm2, different patterns of tumor responses to chemotherapeutic agents were determined. By creating such tiled images and by quantitating cell cycle kinetics, it is possible to gain a more complete understanding of tumor growth and response to treatment, leading to the development of more reliable methods for assessing the clinical behavior of anticancer drugs.
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Yepes M, Sandkvist M, Wong MK, Coleman TA, Smith E, Cohan SL, Lawrence DA. Neuroserpin reduces cerebral infarct volume and protects neurons from ischemia-induced apoptosis. Blood 2000; 96:569-76. [PMID: 10887120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/17/2023] Open
Abstract
Neuroserpin, a recently identified inhibitor of tissue-type plasminogen activator (tPA), is primarily localized to neurons within the central nervous system, where it is thought to regulate tPA activity. In the present study neuroserpin expression and its potential therapeutic benefits were examined in a rat model of stroke. Neuroserpin expression increased in neurons surrounding the ischemic core (ischemic penumbra) within 6 hours of occlusion of the middle cerebral artery and remained elevated during the first week after the ischemic insult. Injection of neuroserpin directly into the brain immediately after infarct reduced stroke volume by 64% at 72 hours compared with control animals. In untreated animals both tPA and urokinase-type plasminogen activator (uPA) activity was significantly increased within the region of infarct by 6 hours after reperfusion. Activity of tPA then decreased to control levels by 72 hours, whereas uPA activity continued to rise and was dramatically increased by 72 hours. Both tPA and uPA activity were significantly reduced in neuroserpin-treated animals. Immunohistochemical staining of basement membrane laminin with a monoclonal antibody directed toward a cryptic epitope suggested that proteolysis of the basement membrane occurred as early as 10 minutes after reperfusion and that intracerebral administration of neuroserpin significantly reduced this proteolysis. Neuroserpin also decreased apoptotic cell counts in the ischemic penumbra by more than 50%. Thus, neuroserpin may be a naturally occurring neuroprotective proteinase inhibitor, whose therapeutic administration decreases stroke volume most likely by inhibiting proteinase activity and subsequent apoptosis associated with focal cerebral ischemia/reperfusion. (Blood. 2000;96:569-576)
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Chen CL, Wong MK, Chen HC, Cheng PT, Tang FT. Correlation of polyelectromyographic patterns and clinical upper motor neuron syndrome in hemiplegic stroke patients. Arch Phys Med Rehabil 2000; 81:869-75. [PMID: 10895997 DOI: 10.1053/apmr.2000.6284] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
OBJECTIVE To investigate the correlation between movement patterns, measured by polyelectromyography (PEMG), and clinical upper motor neuron (UMN) syndrome in stroke patients. DESIGN PEMG patterns, recorded from pairs of flexor-extensor muscles during voluntary maneuvers, and motor outcomes were assessed approximately 1 month after stroke (early stage). Motor outcomes were reassessed 6 months later (late stage). PARTICIPANTS Thirty-nine hemiplegic stroke patients and 18 healthy control subjects. MAIN OUTCOME MEASURES Passive stretch reflexes (PSRs), Brunnstrom's stages, and walking ability. RESULTS Six PEMG patterns, varying from complete reciprocal to complete synchrony, were identified. Higher PEMG pattern scores were associated with better Brunnstrom's stages (r > .80), walking ability (r > .39), and some PSRs (r < -.37). PEMG patterns could separate patterns 1 and 2 from patterns 3 and 4 for patients with early Brunnstrom's stages 1 and 2. Patterns 1 and 2 (reduced agonist electromyographic activities) indicated weakness and resulted in the worst motor outcomes. Patterns 3 and 4 (cocontraction and coactivation) indicated spasticity and associated synergistic movements. Patients with patterns of 5 and 6 (reciprocal electromyographic activities) had more selective motor control. CONCLUSIONS PEMG patterns correlate with clinical UMN syndromes and may allow treatment strategy planning on the basis of underlying motor control, as well as the prediction of final motor outcomes soon after stroke, even in patients who cannot move their legs initially.
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Wang JS, Yang CF, Wong MK, Chow SE, Chen JK. Effect of strenuous arm exercise on oxidized-LDL-potentiated platelet activation in individuals with spinal cord injury. Thromb Haemost 2000; 84:118-23. [PMID: 10928481] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/17/2023]
Abstract
This study investigates how strenuous arm exercise affects oxidized-low density lipoprotein (O(X)-LDL) mediated-platelet activation in patients with SCI. Ten patients with SCI and ten age- and sex-matched healthy subjects exercised strenuously using an arm crank ergometer. The following measurements were taken both when the subjects were at rest, and immediately after exercise: plasma lipid profile, O(X)-LDL mediated platelet aggregability and [Ca(2+)]i, urinary 11-dehydro-thromboxane B2 (11-dehydro-TXB2) and 8-iso-prostaglandin F(2alpha), (8-iso-PG F(2alpha)) contents, and plasma NO metabolite (nitrite plus nitrate) level. Based on these measurements, the major findings of this study can be summarized as follows: 1) the SCI group had higher urinary 8-iso-PGF(2alpha) and 11-dehydro-TXB2 contents, but a lower plasma nitrite plus nitrate level than the control group; 2) at rest, the SCI group had a higher platelet aggregability and [Ca(2+)]i, and O(X)-LDL-potentiated platelet activation than the control group; 3) O(X)-LDL-potentiated platelet aggregation was enhanced by strenuous arm exercise in both groups, but the effect of exercise was more pronounced in the SCI group than in the control group; 4) treating the platelet with L-arginine inhibited O(X)-LDL-potentiated platelet activation in both groups. The study concludes that individuals with SCI had more extensive resting and exercise-enhanced O(X)-LDL-potentiated platelet activation and greater amounts of preformed lipid peroxides than those without SCI. Therefore, supplementation therapy with antioxidants may be needed for patients with SCI, especially in a strenuous arm exercise period.
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Liaw MY, Lin MC, Cheng PT, Wong MK, Tang FT. Resistive inspiratory muscle training: its effectiveness in patients with acute complete cervical cord injury. Arch Phys Med Rehabil 2000; 81:752-6. [PMID: 10857519 DOI: 10.1016/s0003-9993(00)90106-0] [Citation(s) in RCA: 76] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
OBJECTIVE To evaluate if resistive inspiratory muscle training (RIMT) can improve lung function in patients with complete tetraplegia within half a year after trauma. DESIGN A prospective study. The experimental patients received training with a Diemolding Healthcare Division inspiratory muscle trainer for 15 to 20 minutes per session, twice per day, 7 days a week for 6 weeks. SETTING Hospital-based rehabilitation units. PATIENTS Twenty patients who were in their first 6 months of complete cervical cord injury were randomly enrolled into RIMT (10 patients) and control (10 patients) groups. MAIN OUTCOME MEASURE Spirometry, lung volume test, maximal inspiratory pressure, maximal expiratory pressure, and modified Borg scale measurements at rest were performed before training and at the end of 6 weeks of training. RESULTS Most of the pulmonary parameters showed statistically significant improvements within the RIMT and control groups, but the improvements were greater in the RIMT group. In addition, the improvements in total lung capacity, total lung capacity predicted percentage, vital capacity, minute ventilation, forced expiratory volume in 1 second predicted percentage, and the resting Borg scale in the RIMT group showed significantly greater improvement. CONCLUSION RIMT can improve ventilatory function, respiratory endurance, and the perceived difficulty of breathing in patients with complete cervical spinal cord injury within half a year after trauma.
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Chen IC, Cheng PT, Hu AL, Liaw MY, Chen LR, Hong WH, Wong MK. Balance evaluation in hemiplegic stroke patients. CHANG GUNG MEDICAL JOURNAL 2000; 23:339-47. [PMID: 10958036] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/17/2023]
Abstract
BACKGROUND Decreased equilibrium in standing and walking is a common problem associated with hemiplegic stroke patients. Stroke patients with balance problems are prone to falls. In addition to spatial recognition, the appropriate pattern of muscle activity to preserve balance depends on sensory and motor processes. Previous reports have mentioned that the right posterior parietal cortex seems to be predominantly involved in spatial integration. We therefore wanted to conduct a study to quantify and compare the balance control between right hemispheric stroke and left hemispheric stroke patients. METHODS Thirty hemiplegic stroke patients (14 right, 16 left) and 15 age-matched healthy subjects were included in this study. The objective measurement of the basic components of balance control was performed using the SMART Balance Master. The motor status of the hemiplegic limbs was evaluated by Brunnstrom staging. The functional outcome of the stroke patients was evaluated by the functional independence measure (FIM). RESULTS The balance function of stroke patients was significantly worse as compared to that of the healthy subjects especially in dynamic stability. However, different from the other reports, our right hemispheric stroke patients had better balance function than our left hemispheric patients. The locomotion and mobility scores of the FIM were also better in the right hemispheric stroke patients. CONCLUSION This result suggested that the motor function of the healthy limbs of stroke patients may play an important role in their balance function. The results of this study may provide a guide for prescribing a more efficient rehabilitation program for stroke patients.
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