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Kim MJ, Lee WB, Park DH. Comparison of the effect of silicone gel sheets by thickness on excisional scars in pediatric and adolescent patients. Arch Aesthetic Plast Surg 2022. [DOI: 10.14730/aaps.2021.00339] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Background Selecting effective products among the various types of silicone gel sheets can be challenging for surgeons. Therefore, we assessed the effect of silicone gel sheet thickness on surgical scars in pediatric and adolescent patients.Methods From December 2017 to May 2018, we identified patients aged 1–19 years who underwent excision. Among these patients, those who were prescribed 0.3-mm or 1.0-mm-thick silicone sheets were selected. Scars were subjectively evaluated using a questionnaire consisting of seven items. Objective evaluation was performed by two plastic surgeons using the Vancouver Scar Scale (VSS).Results The mean age of the 49 selected patients was 9.78 years. The patients were divided into two groups according to the thickness of the silicone gel sheet used (0.3 mm vs. 1.0 mm). Objective evaluation of the patients’ scars revealed more favorable results in the 0.3 mm group than in the 1.0 mm group (P=0.010). Multivariate analysis of VSS scores indicated that the resulting scars in cases involving the trunk were of poorer quality than those involving facial areas (P=0.015). Additionally, favorable (i.e., below-average) VSS scores were significantly less likely in patients with longer scars (odds ratio, 0.896; 95% confidence interval, 0.834–0.963; P=0.003) or thicker silicone sheets (odds ratio, 0.085; 95% confidence interval, 0.011–0.699; P=0.019).Conclusions The use of thinner silicone gel sheets in children and adolescents resulted in better scars according to subjective evaluations, underscoring the importance of compliance in pediatric patients. The type of operation and surgical lesion should also be considered when planning the management of surgical scars.
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Kim MJ, Lee WB, Lee IJ, Hahn HM, Thai DQ, Kim JY. The investigation of the relation between expansion strategy and outcomes of two-stage expander-implant breast reconstruction. Gland Surg 2022; 11:1-11. [DOI: 10.21037/gs-21-515] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2021] [Accepted: 11/05/2021] [Indexed: 11/06/2022]
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Kim MJ, Lee WB, Park BY. Effect of Morphologically Transformed Acellular Dermal Matrix on Chronic Diabetic Wounds: An Experimental Study in a Calvarial Bone Exposure Diabetic Rat Model. J Surg Res 2021; 272:153-165. [PMID: 34974331 DOI: 10.1016/j.jss.2021.11.009] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2020] [Revised: 10/21/2021] [Accepted: 11/15/2021] [Indexed: 12/12/2022]
Abstract
BACKGROUND The use of acellular dermal matrix on chronic diabetic wounds in clinical practice is hindered by its high cost and difficulty in application. We aimed to acquire experimental evidence on the effect of morphologically transformed acellular dermal matrix on chronic diabetic wounds and investigate how this transformation affects the wound healing mechanism. MATERIALS AND METHODS We developed a new chronic wound model that resembles a diabetic chronic wound as it involves an open wound with partial calvarial bone exposure in diabetic rats. According to treatment materials, rats were assigned into the CONTROL, ADM, and PASTE groups. The wound healing period was subdivided into T1 and T2 (postoperative days 14 and 30, respectively). Three-staged analyses were performed using 3D camera, histological analysis, and real-time quantitative polymerase chain reaction. RESULTS The morphologically transformed acellular dermal matrix showed a compatible treatment rate in the total wound and more rapidly reduced the initial bone exposure area. In the PASTE group, collagen scaffold appeared at a later period and expression levels of epidermal growth factor and epidermal growth factor receptor increased. CONCLUSIONS The transformation of acellular dermal matrix into the pulverized form is thought to contribute to its non-inferior therapeutic effect compared with normal acellular dermal matrix. With respect to the mechanism, the pulverized form reduced the bone exposure area in the early stage and provided a collagen scaffold at a later period. An increase in epithelial growth factors through mechanochemical transformations along with increased contact area contribute to the enhanced healing capacity of the morphologically transformed acellular dermal matrix.
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Affiliation(s)
- Min Ji Kim
- Department of Plastic and Reconstructive Surgery, Ajou University School of Medicine, Suwon, Korea
| | - Woo Beom Lee
- Department of Plastic and Reconstructive Surgery, Ajou University School of Medicine, Suwon, Korea
| | - Bo Young Park
- Department of Plastic and Reconstructive Surgery, School of Medicine, Ewha Womans University, Seoul, South Korea.
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Hahn HM, Lee WB, Lee IJ. The Effects of Subcutaneously Injected Novel Biphasic Cross-Linked Hyaluronic Acid Filler: In Vivo Study. Aesthetic Plast Surg 2021; 45:322-331. [PMID: 33174067 DOI: 10.1007/s00266-020-02033-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2020] [Accepted: 10/21/2020] [Indexed: 12/11/2022]
Abstract
BACKGROUND Biphasic hyaluronic acid (HA) fillers have been used extensively to improve facial skin. However, in some cases, the skin surface is irregular because of the premature loss of HA solution. We propose a new biphasic filler (G-filler) to overcome this problem by using small particles of HA hydrogel instead of HA solution, which can provide a smooth skin surface and good durability. METHOD We evaluated the rheologic properties of G-filler and its physiologic effects after subcutaneous injection in a mouse model by histologic analysis. RESULTS The G-filler showed a similar elastic modulus (G') and complex viscosity (η*) as the conventional biphasic filler, but had a higher viscous modulus (G″) than the conventional monophasic filler. The highest material elasticity (tan δ) value and the lowest percentage elasticity value indicate the rheologic properties of G-filler are closer to those of liquids. After subcutaneous injection of G-filler, collagen content (~ 2-fold) and elastin fibers (~ 6.5-fold) were significantly increased at 12 weeks compared to those of the saline group. Fibronectin (~ 2.6-fold) and the laminin-immunolabeled cell number (~ 6-fold) were also significantly increased at 12 weeks. Significant increases in the CD31-immunoreactive cell numbers of the G-filler groups were observed at 2, 6, and 12 weeks (~ 3.7-fold) compared to those of the saline groups. There were no significant differences between the G-filler and saline groups in patterns of skin thickness and inflammatory cell numbers around loading sites. CONCLUSION These findings demonstrate that the injection of a new biphasic filler with improved rheologic properties can effectively stimulate extracellular matrix production and angiogenesis without safety concerns. NO LEVEL ASSIGNED This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors - www.springer.com/00266 .
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Affiliation(s)
- Hyung Min Hahn
- Department of Plastic and Reconstructive Surgery, Ajou University School of Medicine, 164, World cup-ro, Yeongtong-gu, Suwon-si, Gyeonggi-do, 16499, Republic of Korea
| | - Woo Beom Lee
- Department of Plastic and Reconstructive Surgery, Ajou University School of Medicine, 164, World cup-ro, Yeongtong-gu, Suwon-si, Gyeonggi-do, 16499, Republic of Korea
| | - Il Jae Lee
- Department of Plastic and Reconstructive Surgery, Ajou University School of Medicine, 164, World cup-ro, Yeongtong-gu, Suwon-si, Gyeonggi-do, 16499, Republic of Korea.
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Thai DQ, Lee DH, Lee WB, Hahn HM, Lee IJ. What is the impact of infrapopliteal endovascular intervention on free flap survival in diabetic foot reconstruction? J Orthop Surg Res 2021; 16:42. [PMID: 33430921 PMCID: PMC7802144 DOI: 10.1186/s13018-020-02173-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/23/2020] [Accepted: 12/25/2020] [Indexed: 11/29/2022] Open
Abstract
Background The combination of endovascular intervention and microvascular free flap transfer has been effectively used for chronic ischemic wounds of lower limb. The aim of this study was to determine the influence of angioplasty on free flap survival in diabetic foot ulcer reconstruction. Methods A retrospective research was conducted for 46 diabetic patients with chronic ulcer of the foot. All patients underwent free flap reconstruction because of their non-healing wound with tendon or bone exposure. Patient’s demography, clinical data related to vascular status, vascular intervention, and free flap transfer procedure were collected. Flap survival rate was compared between the group with severe arterial stenosis group and non-severe stenosis group. It was also compared among groups with different revascularization results. Results The average age of patients was 56.2 ± 10.8 years. There were 14 (30.4%) men and 32 (69.6%) women. Of 46 patients, 23 (50%) had severe infrapopliteal arterial stenosis. All 23 patients underwent endovascular intervention. Their final results of the pedal arch were type 1 in 13 patients, type 2A in 7 patients, type 2B in 2 patients, and type 3 in 1 patient. Total flap necrosis was found in 5 (10.9%) cases, marginal necrosis in 4 (8.7%) cases, and wound dehiscence in 4 (8.7%) cases. There was no significant difference in flap loss between severe arterial stenosis patients and non-severe arterial stenosis patients. In the severe arterial stenosis group, after endovascular intervention, patients with type 1 of pedal arch had a significantly lower rate of total flap necrosis than others. There was no association between the use of revascularized recipient artery and flap survival. Conclusions Our study revealed that the quality of pedal arch was crucial for free flap survival. Thus, PTA should aim to re-establish a complete pedal arch to increase wound healing rate and flap success.
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Affiliation(s)
- Duy Quang Thai
- Department of Plastic and Reconstructive Surgery, Ajou University School of Medicine, 164 World cup-ro, Yeongtong-gu, Suwon-si, Gyeonggi-do, 16499, Republic of Korea
| | - Dong Hwan Lee
- Department of Plastic and Reconstructive Surgery, Ajou University School of Medicine, 164 World cup-ro, Yeongtong-gu, Suwon-si, Gyeonggi-do, 16499, Republic of Korea
| | - Woo Beom Lee
- Department of Plastic and Reconstructive Surgery, Ajou University School of Medicine, 164 World cup-ro, Yeongtong-gu, Suwon-si, Gyeonggi-do, 16499, Republic of Korea
| | - Hyung Min Hahn
- Department of Plastic and Reconstructive Surgery, Ajou University School of Medicine, 164 World cup-ro, Yeongtong-gu, Suwon-si, Gyeonggi-do, 16499, Republic of Korea
| | - Il Jae Lee
- Department of Plastic and Reconstructive Surgery, Ajou University School of Medicine, 164 World cup-ro, Yeongtong-gu, Suwon-si, Gyeonggi-do, 16499, Republic of Korea.
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Soh BP, Lee WB, McEntee MF, Kench PL, Reed WM, Heard R, Chakraborty DP, Brennan PC. Mammography test sets: reading location and prior images do not affect group performance. Clin Radiol 2014; 69:397-402. [PMID: 24418670 DOI: 10.1016/j.crad.2013.11.010] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2013] [Revised: 10/29/2013] [Accepted: 11/13/2013] [Indexed: 10/25/2022]
Abstract
AIM To examine how the location where reading takes place and the availability of prior images can affect performance in breast test-set reading. MATERIALS AND METHODS Under optimized viewing conditions, 10 expert screen readers each interpreted a reader-specific set of images containing 200 mammographic cases. Readers, randomly divided into two groups read images under one of two pairs of conditions: clinical read with prior images and laboratory read with prior images; laboratory read with prior images and laboratory read without prior images. Region-of-interest (ROI) figure-of-merit (FOM) was analysed using JAFROC software. Breast side-specific sensitivity and specificity were tested using Wilcoxon matched-pairs signed rank tests. Agreement between pairs of readings was measured using Kendall's coefficient of concordance. RESULTS Group performances between test-set readings demonstrated similar ROI FOMs, sensitivity and specificity median values, and acceptable levels of agreement between pairs of readings were shown (W = 0.75-0.79, p < 0.001) for both pairs of reading conditions. On an individual reader level, two readers demonstrated significant decreases (p < 0.05) in ROI FOMs when prior images were unavailable. Reading location had an inconsistent impact on individual performance. CONCLUSION Reading location and availability of prior images did not significantly alter group performance.
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Affiliation(s)
- B P Soh
- Medical Image Optimisation and Perception Group (MIOPeG), Discipline of Medical Radiation Sciences, University of Sydney, Sydney, NSW, Australia; Department of Diagnostic Radiology, Singapore General Hospital, Singapore.
| | - W B Lee
- Cancer Institute NSW, Alexandria, NSW, Australia
| | - M F McEntee
- Medical Image Optimisation and Perception Group (MIOPeG), Discipline of Medical Radiation Sciences, University of Sydney, Sydney, NSW, Australia
| | - P L Kench
- Medical Image Optimisation and Perception Group (MIOPeG), Discipline of Medical Radiation Sciences, University of Sydney, Sydney, NSW, Australia
| | - W M Reed
- Medical Image Optimisation and Perception Group (MIOPeG), Discipline of Medical Radiation Sciences, University of Sydney, Sydney, NSW, Australia
| | - R Heard
- Medical Image Optimisation and Perception Group (MIOPeG), Discipline of Medical Radiation Sciences, University of Sydney, Sydney, NSW, Australia
| | - D P Chakraborty
- Department of Radiology, University of Pittsburgh, Pittsburgh, PA, USA
| | - P C Brennan
- Medical Image Optimisation and Perception Group (MIOPeG), Discipline of Medical Radiation Sciences, University of Sydney, Sydney, NSW, Australia
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Noh YH, Kim JY, Kim DH, Kim OH, Park J, Kee BS, Sohn DS, Kim D, Chung YH, Kim KY, Lee WB, Kim SS. [Recovery from parkinsonism with N-acetylcysteine-differentiated neurons]. Mol Biol (Mosk) 2013; 47:618-624. [PMID: 24466751 DOI: 10.7868/s0026898413040186] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
The upregulation of dopaminergic neuronal differentiation is necessary for stem cell therapy in Parkinson's disease (PD). In this study, neuronal differentiation efficiency increased by more than 2 times in P19 embryonic stem cells (ESCs) induced by N-acetylcysteine (NAC) and retinoic acid (RA) as compared to RA alone, with suppressed glial differentiation. The majority of NAC-treated stem cells grafted into brains of PD mice differentiated into dopaminergic neurons and persisted well for 6 weeks. Parkinsonism was also greatly improved after grafting NAC-treated cells in comparison to cells treated with only RA. Our results strongly suggest that NAC treatment may be an effective strategy for generating stem cells fated to become dopaminergic neurons for PD clinical therapy.
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Noh YH, Chob HS, Kim DH, Kim OH, Park J, Lee SA, Yang HS, Sohn DS, Kim W, Kim D, Chung YH, Kim KY, Kim SS, Lee WB. N-acetylcysteine enhances neuronal differentiation of P19 embryonic stem cells via Akt and N-cadherin activation. Mol Biol (Mosk) 2012; 46:741-746. [PMID: 23156673] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
We examined whether N-acetylcysteine (NAC) enhanced embryonic body (EB) formation and neuronal differentiation in terms of EB formation, neuronal marker (microtubule-associated protein 2; MAP-2) expression, and neuron maturation using P19 embryonic stem cells. The size and numbers of EBs were greatly increased, together with the up-regulated N-cadherin expression. Also, MAP-2 expression and neurite outgrowth were much increased with activation of serine/threonine protein kinase (Akt) and blocked by addition of an Akt inhibitor (LY294002). Our results suggested that NAC increased EB formation by up-regulating the N-cadherin expression. Furthermore, NAC-enhanced neuronal differentiation was mediated by activation of Akt.
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Affiliation(s)
- Y H Noh
- Department of Cell Biology and Anatomy, College of Medicine, Chung-Ang University, Seoul 156-756, Korea
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King B, Yong HH, Borland R, Omar M, Ahmad AA, Sirirassamee B, Hamann S, O'Connor RJ, Bansal-Travers M, Elton-Marshall T, Lee WB, Hammond D, Thrasher J. Malaysian and Thai smokers' beliefs about the harmfulness of 'light' and menthol cigarettes. Tob Control 2010; 19:444-50. [PMID: 20852322 PMCID: PMC4617534 DOI: 10.1136/tc.2009.034256] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
OBJECTIVE This study explored the extent to which Malaysian and Thai smokers believe "light" and menthol cigarettes are less harmful than "regular" cigarettes and the correlates of these beliefs. METHODS The study used data from wave 1 of the International Tobacco Control Southeast Asia Survey. 2006 adult smokers (95.3% male) from Malaysia and 2000 adult smokers (94.5% male) from Thailand were interviewed face to face in 2005. RESULTS 29% of Malaysian respondents reported currently smoking light cigarettes and 14% menthols, with 19% agreeing that lights are less harmful and 16% agreeing that menthols are less harmful. 38% of Thai respondents reported currently smoking light cigarettes and 19% menthols, with 46% agreeing that lights are less harmful and 35% agreeing that menthols are less harmful. Malaysian smokers reporting current use of light or menthol cigarettes were more likely to believe that they are less harmful. Reported use of lights did not relate to beliefs for Thai respondents. The belief that light and/or menthol cigarettes are less harmful was strongly related to the belief that they have smoother smoke. CONCLUSIONS The experience of smoother smoke is likely to produce some level of belief in reduced harm, regardless of how brands are labelled and whether or not Federal Trade Commission FTC/International Organisation for Standardisation tar, nicotine and carbon monoxide yield figures are used.
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Affiliation(s)
- B King
- VicHealth Centre for Tobacco Control, The Cancer Council Victoria, Carlton, Victoria, Australia.
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Ting SL, Kwok SK, Tsang AHC, Lee WB. Critical elements and lessons learnt from the implementation of an RFID-enabled healthcare management system in a medical organization. J Med Syst 2009; 35:657-69. [PMID: 20703523 DOI: 10.1007/s10916-009-9403-5] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2009] [Accepted: 11/16/2009] [Indexed: 10/20/2022]
Abstract
Healthcare services are complex and life-critical. One mistake in any procedure may lead to irremediable consequences; numerous researchers, thus, introduce information and communication technology to improve quality of services and enhance patient safety by reducing the medical errors. Radio frequency identification (RFID) is considered as one of the emerging tool assist in meeting the challenges of the present situation. In recent years, RFID has been applied in medical organizations for the purpose of managing and tracking medical equipment, monitoring and identifying patients, ensuring that the right medication is given to the right patient, and preventing the use of counterfeit medicine. However, most of the existing literature focuses on demonstrating how RFID can benefit the healthcare industry, whereas little attention has been given to the management issues involved in constructing an RFID project in medical organizations. In this paper, an exploratory case study is conducted in a medical organization to illustrate the development framework and critical issues that should be taken into consideration in the preparation, implementation and maintenance stage of constructing such a project. All the experiences and results discussed in this paper offer valuable and useful insights to steer those who would like to start their journey using RFID in medical organizations.
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Affiliation(s)
- S L Ting
- Department of Industrial and Systems Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong,
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Yong HH, Borland R, Hammond D, Sirirassamee B, Ritthiphakdee B, Awang R, Omar M, Kin F, Zain ZBM, Lee WB, Siahpush M, Fong GT. Levels and correlates of awareness of tobacco promotional activities among adult smokers in Malaysia and Thailand: findings from the International Tobacco Control Southeast Asia (ITC-SEA) Survey. Tob Control 2008; 17:46-52. [DOI: 10.1136/tc.2007.021964] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Abstract
This paper reports the synthesis of high quality LiYF4, BaYF5, and NaLaF4 nanocrystals by high-temperature co-decomposition of precursors in organic solvents. Their bulk counterparts have long been used as efficient luminescent hosts for various applications including lasers, upconversion fluorescence, and quantum cutters. The particles were characterized using TEM, XRD, dynamic light scattering (DLS), and fluorescence spectrometry. Trifluoroacetic acid (CF3COOH) and the reaction temperature were crucial for the formation of NaLaF4 and LiYF4 nanoparticles. NaLaF4 was not formed without using CF3COOH, only LaF3 and NaF mixture was formed. NaLaF4 nanoparticles were obtained only when CF3COOH was added in the reaction solution and the temperature was > or =330 degrees C. For the synthesis of LiYF4,, in the absence of CF3COOH in the reaction, a mixture of YOF and LiYF4 nanoparticles was formed. Pure LiYF4 particles were obtained only until CF3COOH was added in the reaction at 340 degrees C or above. The nanoparticles were easily dispersed in organic solvents include hexane, toluene, and chloroform and formed transparent colloidal solutions. The ease of doping of these as-synthesized host nanoparticles for designed optical properties was assessed. The LiYF4, BaYF5, and NaLaF4 nanoparticles, co-doped with 20% Ytterbium (Yb) and 2% Erbium (Er), showed bright upconversion fluorescence upon 980 nm NIR excitation, confirming the high quality of as-synthesized nanoparticles. These nanoparticles are potential candidates for nano-optical devices, thin films, telecommunication, and bio-probes.
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Affiliation(s)
- G S Yi
- Department of Materials Science and Engineering, National University of Singapore, Singapore 119260, Republic of Singapore
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Abstract
Electron backscattered Kikuchi diffraction methodology was used to identify phases in the interdendrite region of an alloy ZA27. Two Zn-rich hexagonal close-packed structure phases eta and epsilon phases were distinguished using predetermined lattice parameters of the phases. In relation to studies of scanning electron microscopy and X-ray diffraction, electron backscattered diffraction results revealed that the Al-rich precipitates of the alpha phase were from decomposition of the eta'(T), and the four-phase transformation: alpha+epsilon--> T'+eta, had occurred in the epsilon phase after ageing at 150 degrees C for 8 h.
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Affiliation(s)
- S To
- Advanced Manufacturing Technology Research Center, Department of Industrial and Systems Engineering, The Hong Kong Polytechnic University, Hong Kong, China
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Hung WT, Nguyen HT, Lee WB, Rickard MT, Thornton BS, Blinowska A. Diagnostic abilities of three CAD methods for assessing microcalcifications in mammograms and an aspect of equivocal cases decisions by radiologists. Australas Phys Eng Sci Med 2004; 26:104-9. [PMID: 14626848 DOI: 10.1007/bf03178778] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
Radiologists use an "Overall impression" rating to assess a suspicious region on a mammogram. The value ranges from 1 to 5. They will definitely send a patient for biopsy if the rating is 4 or 5. They will send the patient for core biopsy when a rating of 3 (indeterminate) is given. We have developed three methods to aid diagnosis of cases with microcalcifications. The first two methods, namely, Bayesian and multiple logistic regression (with a special "cutting score" technique), utilise six parameter ratings which minimise subjectivity in characterising the microcalcifications. The third method uses three parameters (age of patient, uniformity of size of microcalcification and their distribution) in a multiple stepwise regression. For both training set and test set, all three methods are as good as the two radiologists in terms of percentages of correct classification. Therefore, all three proposed methods potentially can be used as second readers.
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Affiliation(s)
- W T Hung
- Key University Research Centre for Health Technologies, University of Technology, Sydney, Australia
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Lee WK, Lee KW, Kwak EJ, Yang SW, Yang KS, Park JC, Joo HS, Lee WJ, Lee WB. Effects of environmental endocrine disruptors on the sex differentiation in Korean rockfish, Sebastes schlegeli. Water Sci Technol 2003; 47:65-70. [PMID: 12830942] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
The effects of estradiol-17beta, methyltestosterone, tributyltin, bisphenol A and 2,4-dinitrophenol on sex differentiation were investigated in the Korean rockfish, Sebastes schlegeli. The 51 day-old fry with undifferentiated gonads were fed with food containing the chemicals at 0.05, 0.5, 5, 50 and 100 micro/g diet for 29 days. Sex ratio and gonadal abnormality after the chemical treatment were determined by histological examination of gonads. In control group, the sex ratio of fry was 1:1.3 (female:male), and more males than females appeared. The sex of fry fed with estradiol-17beta at 5, 50 and 100 micro/g diet was all females. Feminization of the fry was induced by exogenic estradiol-17beta. In the methyltestosterone group, sex ratio of fry was 1:10.2 in 0.05 micro/g diet, 1:2.4 in 0.5 micro/g diet, 1:3.1 in 5 micro/g diet, 1:1.2 in 50 micro/g diet and 1:2.3 in 100 micro/g diet. Masculinization of the fry was induced by methyltestosterone at the lowest concentration. Furthermore, intersex of the fry was observed. The number of intersex fry was 23.3, 25.0 and 35.3 at 0.5, 5 and 50 micro/g diet of methyltestosterone, respectively. Sex ratio of bisphenol A group showed no difference with that of the control. The sex of fry fed with 2,4-dinitrophenol at 5, 50 and 100 micro/g diet was all females. 2,4-dinitrophenol should be considered as a new member of endocrine disruptors. In tributyltin group, the sex ratio of fry at 100 micro/g diet of tributyltin was 5.4:1. Tributyltin induced the feminization of the fry at the highest dose. Tributyltin showed an estrogenic effect in the Korean rockfish in contrast to an androgenic effect in gastropods.
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Affiliation(s)
- W K Lee
- Department of Aquaculture, Yosu National University, Chonnam 550-749, Korea.
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Park JC, Lee JC, Oh JY, Jeong YW, Cho JW, Joo HS, Lee WK, Lee WB. Antibiotic selective pressure for the maintenance of antibiotic resistant genes in coliform bacteria isolated from the aquatic environment. Water Sci Technol 2003; 47:249-253. [PMID: 12639037] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Coliform bacteria isolated from the aquatic environment were investigated for antibiotic susceptibility and detailed structures of class 1 integrons. A high proportion of isolates were found to be resistant to sulfamethoxazole, aminoglycosides, and beta-lactams. The 750 (53.6%) isolates were resistant to one or more of the antibiotics tested out of 1,400 coliform bacteria. Based on the MIC of antibiotics and antibiogram, 150 isolates were selected and further studied for class 1 integrons. The intI1 gene was found in 36 (24.0%) of the 150 isolates. Twelve isolates carried the gene cassettes responsible for antibiotic resistance, while no gene cassettes were found in 24 isolates. Seven different genes, dfrA5, dfrA7, dfrA12, dfrA17, aaA2, aaA5, and aad(3'), were detected in gene cassettes. The dfrA and aad genes located on class 1 integrons were responsible for resistance to trimethoprim and aminoglycosides. The remaining 24 coliform bacteria had the incomplete or non-functional class 1 integrons. These results indicated that antibiotic selective pressures may play an important role to maintain gene cassettes of class 1 integrons and in the absence of sustained antibiotic pressures, such as the aquatic environment, coliform bacteria may carry empty or non-functional class 1 integrons.
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Affiliation(s)
- J C Park
- Dept of Microbiology, Seonam University, Chunpook, 590-711, Korea.
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Kim JO, Lee WB. Biodegradation of gaseous benzene with microbial consortium in a biofilter. Environ Technol 2002; 23:437-444. [PMID: 12088371 DOI: 10.1080/09593332508618401] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The objective of this study was to investigate the biodegradation of gaseous benzene in a biofilter inoculated with benzene-oxidizing microorganisms. The biofilter performance was monitored in terms of benzene removal efficiency and carbon dioxide production. The biofilter was capable of achieving as much as 96% benzene removal efficiency at a residence time of 2 min and an inlet concentration of 220 ppm. During operation with an inlet benzene of 220 ppm, the maximum elimination capacity of the biofilter was 483 g of C6H6 m(-3) day(-1). Under the same conditions, carbon dioxide with a concentration of up to 726 ppm was produced. It was found that carbon dioxide wasproduced at a rate of 608 mg day(-1), which corresponded to a volume of 0.35 l day(-1). Observable features of the microorganisms, meaning microbial activity occurrence in the biofilter, were investigated with the microscopy analysis.
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Affiliation(s)
- J O Kim
- Department of Environmental Education, Mokpo National University, Muan-Kun, Chonnam, Republic of Korea
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Chang TK, Chen J, Lee WB. Differential inhibition and inactivation of human CYP1 enzymes by trans-resveratrol: evidence for mechanism-based inactivation of CYP1A2. J Pharmacol Exp Ther 2001; 299:874-82. [PMID: 11714871] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/22/2023] Open
Abstract
trans-Resveratrol (3,5,4'-trihydroxy-trans-stilbene) has been reported to confer chemoprotection against 7,12-dimethylbenz[a]anthracene (DMBA)-induced carcinogenicity in a murine model. A potential mechanism for this effect by trans-resveratrol is inhibition of DMBA-bioactivating cytochrome P450 (CYP) enzymes such as CYP1B1, CYP1A1, and CYP1A2. In the present study, we examined in detail the in vitro inhibitory effects of trans-resveratrol on these three human CYP enzymes. trans-Resveratrol decreased 7-ethoxyresorufin O-dealkylation activity catalyzed by human recombinant CYP1B1, CYP1A1, and CYP1A2 in a concentration-dependent manner and by a mixed type of inhibition. This direct inhibition was enzyme-selective, as judged by the differences in the apparent K(i) values (0.8 +/- 0.1 microM, 1.2 +/- 0.1 microM, and 15.5 +/- 1.1 microM for CYP1B1, CYP1A1, and CYP1A2, respectively). Preincubating recombinant CYP1A2 or human liver microsomes with trans-resveratrol and NADPH prior to the initiation of substrate oxidation resulted in a time- and concentration-dependent decrease in catalytic activity. The inactivation of liver microsomal CYP1A2 by trans-resveratrol required NADPH, was not reversible by dialysis, and was not affected by the trapping agents glutathione, N-acetylcysteine, catalase, or superoxide dismutase, but was attenuated by a CYP1A2 substrate, imipramine. Analysis of a panel of individual human liver microsomes showed intersample differences in the response to the in vitro inactivation by trans-resveratrol. In contrast to CYP1A2, CYP1B1 was not subject to inactivation by this compound and the reduction in CYP1A1 activity was time- but not concentration-dependent. In summary, trans-resveratrol differentially inhibited human CYP1 enzymes and this occurred by two distinct mechanisms: direct inhibition (mainly CYP1B1 and CYP1A1) and mechanism-based inactivation (CYP1A2).
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Affiliation(s)
- T K Chang
- Faculty of Pharmaceutical Sciences, University of British Columbia, Vancouver, British Columbia, Canada.
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Chae HS, Bach JH, Lee MW, Kim HS, Kim YS, Kim KY, Choo KY, Choi SH, Park CH, Lee SH, Suh YH, Kim SS, Lee WB. Estrogen attenuates cell death induced by carboxy-terminal fragment of amyloid precursor protein in PC12 through a receptor-dependent pathway. J Neurosci Res 2001; 65:403-7. [PMID: 11536323 DOI: 10.1002/jnr.1167] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
In the present study, we investigated effects of estrogen on cell death induced by carboxy-terminal fragment of amyloid precursor protein (CT), a candidate causative substance in the pathogenesis of Alzheimer's disease. 17 beta-Estradiol attenuated CT-induced cell death in PC12 cells, whereas 17 alpha-estradiol, nonestrogenic stereoisomer, did not exert any significant protective effect on CT-induced cell death. These results suggest that protective effects of estrogen may be mediated by estrogen receptor (ER) in PC12 cells. To confirm the results, we determined the effects of tamoxifen, an estrogen receptor antagonist. Tamoxifen blocked the protective effects of 17 beta-estradiol, although it did not affect those of 17 alpha-estradiol. Overall, it might be thought that the protective effect of estradiol on CT-induced cell death is achieved by hormonal properties mediated through the estrogen receptor rather than the structural properties as a reducing agent.
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Affiliation(s)
- H S Chae
- Department of Anatomy, College of Medicine, Chung-Ang University, Dongjak-ku, Seoul, Korea
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Bach JH, Chae HS, Rah JC, Lee MW, Park CH, Choi SH, Choi JK, Lee SH, Kim YS, Kim KY, Lee WB, Suh YH, Kim SS. C-terminal fragment of amyloid precursor protein induces astrocytosis. J Neurochem 2001; 78:109-20. [PMID: 11432978 DOI: 10.1046/j.1471-4159.2001.00370.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
One of the pathophysiological features of Alzheimer's disease is astrocytosis around senile plaques. Reactive astrocytes may produce proinflammatory mediators, nitric oxide, and subsequent reactive oxygen intermediates such as peroxynitrites. In the present study, we investigated the possible role of the C-terminal fragment of amyloid precursor protein (CT-APP), which is another constituent of amyloid senile plaque and an abnormal product of APP metabolism, as an inducer of astrocytosis. We report that 100 nM recombinant C-terminal 105 amino acid fragment (CT105) of APP induced astrocytosis morphologically and immunologically. CT105 exposure resulted in activation of mitogen-activated protein kinase (MAPK) pathways as well as transcription factor NF-kappaB. Pretreatment with PD098059 and/or SB203580 decreased nitric oxide (NO) production and nuclear factor-kappa B (NF-kappaB) activation. But inhibitors of NF-kappaB activation did not affect MAPKs activation whereas they abolished NO production and attenuated astrocytosis. Furthermore, conditioned media derived from CT105-treated astrocytes enhanced neurotoxicity and pretreatment with NO and peroxynitrite scavengers attenuated its toxicity. These suggest that CT-APP may participate in Alzheimer's pathogenesis through MAPKs- and NF-kappaB-dependent astrocytosis and iNOS induction.
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Affiliation(s)
- J H Bach
- Department of Anatomy, College of Medicine, BioGrand Inc., and MRC, Chung-Ang University, 221 Huksuk-dong, Dongjak-ku, Seoul 156-756, Korea
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Lee MW, Park SC, Chae HS, Bach JH, Lee HJ, Lee SH, Kang YK, Kim KY, Lee WB, Kim SS. The protective role of HSP90 against 3-hydroxykynurenine-induced neuronal apoptosis. Biochem Biophys Res Commun 2001; 284:261-7. [PMID: 11394871 DOI: 10.1006/bbrc.2001.4938] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
3-hydroxykynurenine (3HK), an endogenous metabolite of tryptophan in the kynurenine pathway, is a potential neurotoxin in several neurodegenerative disorders. Stabilizing protein structure, heat shock proteins (HSPs) have diverse roles as molecular chaperones to mediate stress tolerance. In the present study, we investigated the possible protective role of HSPs against 3HK induced neuronal cell death. Here we report that 3HK induced in a dose- and time-dependent manner neuronal cell death in neuroblastoma SK-N-SH cells. The cell death showed characteristic apoptotic features such as cell shrinkage, plasma membrane blebbing, chromatin condensation, and nuclear condensation and fragmentation. Furthermore, SK-N-SN cells were protected from 3HK induced cytotoxicity by prior elevation of HSPs expression. Our results show that the protective effect was abolished by HSP90 anti-sense oligonucleotides while not by HSP27 and HSP70 anti-sense oligonucleotides. Also, our result shows that HSP90 effectively inhibits caspases activities leading to the apoptosis. These results suggest that 3HK induces apoptosis in neuroblastoma SK-N-SN cells and that HSP90 is major contributing protein component of protection against 3HK induced apoptosis.
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Affiliation(s)
- M W Lee
- Department of Anatomy, College of Medicine, Chung-Ang University, Seoul, Korea
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Sen HA, O'Halloran HS, Lee WB. Case reports and small case series: topiramate-induced acute myopia and retinal striae. Arch Ophthalmol 2001; 119:775-7. [PMID: 11346412] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/16/2023]
Affiliation(s)
- H A Sen
- Department of Ophthalmology, University of Kentucky, Lexington, KY 40536, USA
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O'Halloran HS, Berger JR, Lee WB, Robertson DM, Giovannini JA, Krohel GB, Meckler RJ, Selhorst JB, Lee AG, Nicolle DA, O'Day J. Acute multifocal placoid pigment epitheliopathy and central nervous system involvement: nine new cases and a review of the literature. Ophthalmology 2001; 108:861-8. [PMID: 11320014 DOI: 10.1016/s0161-6420(01)00565-6] [Citation(s) in RCA: 72] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022] Open
Abstract
OBJECTIVE The authors describe nine new cases of acute multifocal placoid pigment epitheliopathy (AMPPE) with associated central nervous system (CNS) involvement and permanent visual sequelae. The study includes a review of the literature and discussion of evaluation, management, and treatment options. DESIGN Retrospective, noncomparative case series. PARTICIPANTS Nine patients were identified with AMPPE and CNS involvement in addition to 22 patients reviewed in the literature. MAIN OUTCOME MEASURES A review of nine patients with AMPPE and CNS involvement was performed. Charts were reviewed for age, gender, preceding viral prodromes, visual acuity, ophthalmologic examination findings, CNS findings, and treatment. RESULTS Thirty-one patients (nine new patients) were diagnosed with AMPPE and various degrees of CNS involvement. Ages ranged from 8 to 54 years, with an average of 27 years. Twenty-one males (68%) and 10 females (32%) were identified. Eleven patients (35%) had antecedent viral illnesses. Visual acuity was variable and ranged from 20/20 to count fingers. The spectrum of CNS findings ranged from headaches to sagittal sinus thrombosis. CONCLUSIONS Acute multifocal placoid pigment epitheliopathy can be associated with CNS abnormalities and permanent visual deficits. Neuroimaging, lumbar puncture, and cerebral angiography analysis provide useful diagnostic tools when CNS involvement is suspected. Intravenous corticosteroids and collaboration with neurovascular colleagues should be considered in these situations. In cases complicated by CNS arteritis, immunosuppressive agents can be a beneficial adjunct to corticosteroids.
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Affiliation(s)
- H S O'Halloran
- Department of Ophthalmology, University of Kentucky, Lexington, KY 40536, USA.
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Abstract
In this cadaveric study, the safety and accuracy of a specially designed guide device for the placement of thoracic pedicle screws was investigated in a normal anatomical situation. Five embalmed human cadaveric thoracic spines (T1-12) were used for the study of transpedicular screw placement in the thoracic spine. Overall 120 screws were placed at all thoracic levels. The screws were inserted bilaterally in the thoracic pedicles by using a specially designed guide device. No radiographs or other imaging studies were obtained. Following screw placement, computerized tomography scans were performed to evaluate the accuracy of the pedicle screw positioning. Seven (5.8%) of the screws penetrated the pedicle wall or the vertebral body (VB) cortex. Two screws (1.7%) penetrated the medial wall of the pedicle. Two screws (1.7%) penetrated the lateral wall of the pedicle, and one screw (0.8%) penetrated the lateral wall of the pedicle and the anterior VB cortex simultaneously. Two screws (1.7%) penetrated the anterior VB cortex. Compared with the results of other studies, the findings here indicate that using this device to guide the placement of thoracic pedicle screws can significantly reduce the incidence of pedicle penetration, particularly in the medial wall.
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Affiliation(s)
- J S Jang
- Department of Neurosurgery, Wooridul Spine Hospital, Seoul, Korea.
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Abstract
We report five cases of bilateral eye injuries from airbag deployment in motor vehicle crashes and review the world's literature on ocular injuries associated with airbags. The cases in the literature were identified by cross-referencing Medline searches from airbags and ocular injuries. Additional cases were identified after review of references from each article in the search. An additional 89 cases from the literature were identified and are included for discussion. Patients were treated individually in a noncontrolled, nonrandomized fashion according to the nature of each injury with regular follow-up examinations in clinic. Of the 94 cases studied, 24 (27%) were bilateral eye injuries, and 15 (16%) patients were wearing spectacles at the time of the accident. The most common injuries included corneal abrasions, eyelid trauma, and hyphemas. Outcomes ranged from complete resolution of symptoms and return of normal visual acuity to primary enucleation. This report describes the wide spectrum of eye injuries that may occur after airbag deployment. We suggest a management plan for the evaluation and treatment of the ocular complications of airbag-related trauma.
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Affiliation(s)
- W B Lee
- Department of Ophthalmology, University of Kentucky, 800 Rose St., Lexington, KY 40536, USA
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Abstract
BACKGROUND Complex sclerosing lesion (CSL) and its smaller counterpart, the radial scar (RS), are frequently seen pathological entities. They are clinically asymptomatic and, prior to the implementation of mammographic screening, were most commonly found incidentally during pathological examination of other biopsied lesions. Complex sclerosing lesions are being detected regularly on mammograms due to widespread screening; many of their features resemble those of malignancy. Management varies and has been controversial. METHODS Twenty-three cases of CSL detected during the first prevalent round of screening at BreastScreen Western Sydney (from February 1993 until June 1995) are presented and reviewed. Assessment was by a combination of radiological, clinical and cytological work-up prior to surgical biopsy. In addition, 126 spiculated carcinomas detected in the same period were reviewed and compared. RESULTS Fourteen RS/CSL (62%) had lucent centres and nine (38%) had a central mass; three had been diagnosed provisionally as RS/CSL. Spicule lengths ranged from 25 to 90 mm; central masses ranged from 5 to 50 mm; and mass:spicule length ratio ranged from 1.2:1 to 1:10. Calcification (benign or indeterminate) was present in six cases (29%). No RS/CSL contained 'suspicious' calcifications, whereas 120 of 126 carcinomas (95%) had a central mass and six (5%) had a lucent centre (spicule lengths: 10-90 mm; central mass: 5-40 mm; and mass:spicule length ratio: 1.1:1-1:10). Twenty-one spiculated carcinomas (17%) contained microcalcifications (14 benign or indeterminate; seven suspicious). Provisional radiological diagnosis (PRD) after mammogram, with or without ultrasound, for histologically confirmed RS/CSL, was RS/CSL in 18 cases (78%), carcinoma in four cases (17%) and equivocal in one case (5%). For eight (6.5%) spiculate carcinomas the PRD was RS/CSL prior to histological diagnosis. The RS/CSL were detected with equal frequency in right and left breasts, and 22 (96%) lesions occurred in the upper breast. Seven RS/CSL (31%) and 83 spiculated carcinomas (65%) had been described as 'palpable' but most were subtle. Twelve fine-needle aspiration biopsies were performed (six 'palpable' lesions (no radiological guidance); four with ultrasound guidance and two with stereotactic guidance), and five (62.5%) of eight adequate lesions were reported as benign, two (25%) were reported as atypical, and one (12.5%) was reported as suspicious. CONCLUSIONS Definitive mammographic and sonographic differentiation of RS/CSL and stellate-type carcinoma is impossible. For screen-detected lesions that may be RS/CSL, the appropriate surgical procedure is a small but adequate biopsy using guidewire or other localization methods with optimal cosmetic incision.
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Affiliation(s)
- O A Ung
- Division of Surgery,Westmead Hospital, New South Wales, Australia.
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Chang TK, Lee WB, Ko HH. Trans-resveratrol modulates the catalytic activity and mRNA expression of the procarcinogen-activating human cytochrome P450 1B1. Can J Physiol Pharmacol 2000; 78:874-81. [PMID: 11100935] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
Abstract
The present study was performed to determine if trans-resveratrol (3,5,4'-trihydroxy-trans-stilbene) modulates the catalytic activity and gene expression of cytochrome P450 1B1 (CYP1B1). In vitro, trans-resveratrol decreased human recombinant CYP1B1-catalyzed 7-ethoxyresorufin O-dealkylation activity, with an IC50 value of 1.4 +/- 0.2 microM (mean +/- SEM). Enzyme kinetic analysis indicated that trans-resveratrol inhibited CYP1B1 enzyme activity by a mixed-type inhibition and the apparent Ki was 0.75 +/- 0.06 microM. To determine if trans-resveratrol modulates constitutive CYP1B1 gene expression, cultured MCF-7 human breast carcinoma cells were treated with trans-resveratrol. As indicated by RT-PCR analysis, treatment of MCF-7 cells with 10 microM trans-resveratrol decreased relative CYP1B1 mRNA levels after 5 h, but not after 1.5 or 3 h, of exposure. trans-Resveratrol treatment at 5, 7.5, 10, or 20 microM for 5 h produced a concentration-dependent decrease in CYP1B1 mRNA levels. The extent of suppression was approximately 50% at 20 microM concentration. The suppressive effect was not a consequence of a toxic response to the compound as assessed by a cell proliferation assay. Overall, our novel finding that trans-resveratrol inhibits the catalytic activity and suppresses the constitutive gene expression of CYP1B1 leads to the possibility that this nutraceutical confers protection against toxicity and carcinogenicity induced by compounds that undergo CYP1B1-catalyzed bioactivation.
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Affiliation(s)
- T K Chang
- Division of Pharmacology and Toxicology, Faculty of Pharmaceutical Sciences, The University of British Columbia, Vancouver, Canada.
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Katzorke M, Lee WB. Creating world-class supply chains. Hosp Mater Manage Q 2000; 22:1-9. [PMID: 11183379] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/19/2023]
Abstract
This article will share knowledge in two areas: The elements of world-class supply chains and the linking processes from customers' customers to suppliers' suppliers and the management approaches needed to engage the people and the organization in an effective implementation process to achieve world-class status.
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Kim WI, Lee WB, Song K, Kim J. Identification of a putative DEAD-box RNA helicase and a zinc-finger protein in Candida albicans by functional complementation of the S. cerevisiae rok1 mutation. Yeast 2000; 16:401-9. [PMID: 10705369 DOI: 10.1002/(sici)1097-0061(20000330)16:5<401::aid-yea531>3.0.co;2-r] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
We identified two novel genes, CHR1 and CSR1, of the fungal pathogen Candida albicans, by functional complementation of the Saccharomyces cerevisiae rok1 mutation. The Rok1 protein is a member of the DEAD protein family of ATP-dependent RNA helicases. ROK1 is required for cell cycle progression and also for rRNA processing. The CHR1 gene product of 578 amino acids is highly homologous to the Rok1 protein (54% identity) and is considered to be a putative DEAD-box RNA helicase. We predict that the CSR1 gene encodes a 73 kDa protein of 612 amino acids with five zinc-finger motifs at the C-terminal region. CHR1 or CSR1 on a high-copy number plasmid showed a slow-growth phenotype in a condition where the ROK1 expression is turned on from the GAL1 promoter. This result is consistent with the lethality caused by the ROK1 overexpression. We conclude that CHR1 encodes a functional homologue of Rok1 protein and CSR1 is a heterologous suppressor of the rok1 mutation.
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Affiliation(s)
- W I Kim
- Department of Microbiology, College of Natural Sciences, Chungnam National University, Taejeon 305-764, South Korea
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Abstract
The authors describe a patient with bilateral papilledema, visual field abnormalities, poorly reactive pupils, meningeal enhancement on cranial MRI, and diffuse brain parenchymal hypervascularity. The opening pressure at the time of lumbar puncture was normal, and results of other CSF studies were normal. All abnormalities resolved with home oxygen therapy.
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Affiliation(s)
- H S O'Halloran
- Department of Ophthalmology, University of Kentucky, Lexington 40536, USA.
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Abstract
We report the details of a patient with an unusual form of ophthalmoplegic migraine resulting in permanent vertical misalignment of the affected eye. The presentation, history, and ophthalmologic examination are reported as well as disease course and follow-up complications. We review the literature on ophthalmoplegic migraine with discussion regarding typical presentation, methods of diagnosis, and other diseases which may cause diagnostic confusion. In light of current case reports on ophthalmoplegic migraine, this is the first documented example with a permanent deficit.
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Affiliation(s)
- H S O'Halloran
- Department of Ophthalmology, University of Kentucky, 800 Rose Street, Lexington, KY 40536, USA
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Abstract
The state in which cells can inhabit other cells without damage is known as emperipolesis. Emperipolesis has been found in various physiological and pathological conditions. We performed a study of emperipolesis of erythroblasts within Kupffer cells in the human fetal liver. We found that Kupffer cells, identified by CD68 immunolabeling, contained 4-8 erythroblasts in a hypertrophic cytoplasm on light microscopy. Emperipoletic erythroblasts were present in various maturation stages from proerythroblast to reticulocyte. By electron microscopy, we found that erythroblasts occupied membrane-bound vacuoles that were separated from each other by thin partitions of Kupffer cell cytoplasm. Neither emperipoletic erythroblasts nor their Kupffer cell hosts showed evidence of damage. Emperipoletic cells in mitosis were found, which suggests the capacity for the proliferation of erythroblasts within Kupffer cells. Some Kupffer cells were seen to contain both emperipoletic cells and phagosomes, without evidence of interaction. Erythroblasts and other hemopoietic cells were also found to be closely associated with the sinusoidal surface of Kupffer cells. However, intercellular junctions, if present, were inconspicuous. On occasion, Kupffer cells engorged with erythroblasts nearly occluded the sinusoidal lumen. Our results demonstrate that emperipolesis of erythroblasts within Kupffer cells occurs in human fetal hepatic hemopoiesis. We suggest that emperipolesis may be one of the mechanisms that support the maturation of erythroblasts in the fetal liver.
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Affiliation(s)
- W B Lee
- Department of Anatomy, College of Medicine, Chung-Ang University, Heuk Suk Dong, Dong Jak Ku, Seoul, 156-756 Korea.
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Alhadainy HA, Himel VT, Lee WB, Elbaghdady YM. Use of a hydroxylapatite-based material and calcium sulfate as artificial floors to repair furcal perforations. Oral Surg Oral Med Oral Pathol Oral Radiol Endod 1998; 86:723-9. [PMID: 9868732 DOI: 10.1016/s1079-2104(98)90211-6] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
OBJECTIVE The purpose of this study was to evaluate a hydroxylapatite-based material and calcium sulfate when each was used under a resin-modified glass ionomer cement to repair furcation perforations. STUDY DESIGN Perforations of pulp chamber floors were made in 72 teeth of 9 dogs. Perforations were divided into 3 equal-sized groups and repaired with resin-modified glass ionomer either alone or over an artificial floor. The artificial floor was either a hydroxylapatite-based material or calcium sulfate. Three dogs were killed at each of 3 intervals (1, 3, and 6 months). The tissue response to the tested materials was evaluated clinically, radiographically, and histologically. RESULTS The hydroxylapatite-based material showed the highest radiographic success; this was followed by calcium sulfate and glass ionomer. From histologic evaluation, the average success rate was found to be 67% for calcium sulfate, 62% for the hydroxylapatite-based material, and 59% for glass ionomer. However, there was no statistical significant difference with the resin-modified glass ionomer when it was used alone and when it was used over a barrier. There was also no significant difference between the hydroxylapatite-based material and the calcium sulfate when they were used as artificial floors. CONCLUSION The use of an artificial floor may not be necessary when flowable resin-modified glass ionomer cements are used.
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Affiliation(s)
- H A Alhadainy
- Department of Restorative Dentistry, College of Dentistry, University of Tanta, Egypt
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O'Halloran HS, Pearson PA, Lee WB, Susac JO, Berger JR. Microangiopathy of the brain, retina, and cochlea (Susac syndrome). A report of five cases and a review of the literature. Ophthalmology 1998; 105:1038-44. [PMID: 9627654 DOI: 10.1016/s0161-6420(98)96005-5] [Citation(s) in RCA: 119] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
OBJECTIVE This study reports five new cases of microangiopathy of the brain, retina, and cochlea (Susac syndrome) and reviews the world's literature. DESIGN Five cases were systematically studied by the authors. The cases in the literature were identified through Medline searches for Susac syndrome; microangiopathy of the brain, retina, or ear; and cross-referencing the indexes of each retrieved article. PARTICIPANTS The number of new patients studied in this report was five. An additional 41 patients were culled from the literature. INTERVENTION Patients were treated with corticosteroids, antineoplastic agents, and other methods in a noncontrolled, nonrandomized fashion. MAIN OUTCOME MEASURES With respect to therapeutic intervention, the main clinical outcome measures were return of vision, improvement of neurologic and psychiatric manifestations, and recovery of auditory function. Alterations of abnormalities observed by cranial magnetic resonance imaging also were monitored. RESULTS Of 46 identified patients, 39 were women. The mean age of the patients was 30 years. Forty-one patients (89%) had arterial occlusions, which were bilateral in 60%. Thirty-one patients (67%) reported hearing loss. Twenty patients (44%) had a global encephalopathy, but other neurologic manifestations were common. The mean duration of the illness was 46.7 months. CONCLUSION This rare syndrome is more common than previously thought, has a strong female preponderance, and often can be identified at an early stage with a careful history and physical examination. Magnetic resonance imaging of the brain often shows lesions suggestive of multiple sclerosis. Fluorescein angiography may show arteriolar wall hyperfluorescence. Early treatment with corticosteroids often is, although not invariably, associated with a good prognosis. The disease appears to be self-limited in most patients.
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Affiliation(s)
- H S O'Halloran
- Department of Ophthalmology, University of Kentucky College of Medicine, Lexington 40536-0284, USA
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Rhee JY, Lee WB, Kim J. Characterization and intracellular localization of the Rok1 protein involved in yeast cell division. Mol Cells 1998; 8:68-74. [PMID: 9571634] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
The ROK1 gene is essential for the cell cycle progression in Saccharomyces cerevisiae. ROK1 has been predicted to encode an ATP-dependent RNA helicase of the DEAD-box family. We have analyzed the ROK1 gene expression both at the protein and RNA levels. Polyclonal antibodies were raised against trpE::rok1 hybrid proteins and were affinity purified by using lacZ::rok1 hybrid proteins. Western blot experiments using anti-Rok1 antibodies revealed a single protein band of 64 kDa which is an expected size from the Rok1 amino acid sequence. Indirect immuno-fluorescence showed that the Rok1 protein is localized predominantly to the cytoplasm of the vegetatively growing cells. We have detected immunocross-reactive homologs of Rok1p in Candida albicans and Drosophila melanogaster.
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Affiliation(s)
- J Y Rhee
- Department of Microbiology, College of Natural Sciences, Chungnam National University, Taejeon, Korea
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37
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Abstract
The fine-needle aspiration cytology (FNA) from 12 mammographically detected, histologically confirmed radial scar/complex sclerosing lesions (RS/CSL) and their corresponding mammography were reviewed. Six aspirates were obtained by palpation, four by ultrasound guidance, and two by stereotactic guidance. Of the eight lesions with sufficient material five (62.5%) were reported as benign, two (25%) as atypical, and one (12.5%) as suspicious. It is proposed that FNA for RS/CSL should not be performed, and lesions require excision for histologic assessment.
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Affiliation(s)
- M L Greenberg
- Breastscreen Western, Sydney, Australia (part of Breastscreen New South Wales)
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38
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Abstract
Three species of British voles, the bank vole Clethrionomys glareolus, the field vole Microtus agrestis and the water vole Arvicola terrestris were maintained on diets of seed and plant leaf material to investigate changes in gut anatomy. C. glareolus and M. agrestis showed significant changes in most regions of the gut; they developed longer and heavier tracts when on a high-fibre diet. This response may be important in enabling these animals to withstand seasonal changes in diet quality.
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Affiliation(s)
- W B Lee
- Department of Zoology, University of Glasgow, UK
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39
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Abstract
Eosinophilic granulopoiesis was investigated in human fetal liver during intrauterine life from 5 to 34 weeks of gestation. Eosinophilic granulocytes were observable for the first time at 5 weeks in the hepatic laminae and were frequently found in the late embryonic period around the large vessels and in the mesenchyme adjacent to the liver. Eosinophilic granulopoiesis increased gradually in the hepatic laminae (P < 0.01) after 20 weeks of gestation and in the portal areas (P < 0.05) after 16 weeks of gestation. The proportions of each cellular differentiation stage were relatively constant during fetal life, but a greater number of mature eosinophils were observed in the portal areas. Eosinophilic granulopoiesis was evident in all the hepatic tissue components, but developed more actively in portal areas than in hepatic laminae during intrauterine life. Eosinophilic granulopoiesis preceded both erythropoiesis and megakaryopoiesis in the human embryonic liver. Although the latter two occurred mainly in the hepatic laminae, eosinophilic granulopoiesis developed more actively in the portal areas, where it exhibited increasing activity along with the development of the component cells.
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Affiliation(s)
- D S Sohn
- Department of Anatomy, College of Medicine, Chung-Ang University, Seoul, Korea
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40
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Lee WB, Wong KP. C.T. demonstration of thrombosis of the portal venous system. Australas Radiol 1988; 32:360-4. [PMID: 3202748 DOI: 10.1111/j.1440-1673.1988.tb02753.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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41
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Lee WB. Left gastric and coeliac lymph nodes: a problem area for C.T. staging of carcinoma of the gastro-oesophageal junction. Australas Radiol 1988; 32:230-1. [PMID: 3190609 DOI: 10.1111/j.1440-1673.1988.tb02727.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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42
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Mincer HH, Jennings BR, Turner JE, Lee WB. Detection of human papovavirus antigen in oral papillary lesions. Oral Surg Oral Med Oral Pathol 1985; 59:516. [PMID: 2989753 DOI: 10.1016/0030-4220(85)90094-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
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43
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44
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Abstract
1. In adult conscious sheep the pressor actions of infused angiotensin II were prevented by the concomitant intravenous infusions of sodium nitroprusside. The effect of such intravenous infusions of angiotensin II on the cardiac baroreflex response to transient rises in arterial pressure caused by intravenous phenylephrine was studied. 2. Intravenous infusion of angiotensin II caused a reduction in pulse interval in the absence of any change in arterial pressure. It also caused a reduction in baroreflex sensitivity measured by determining the relation between pulse interval and systolic pressure during the rise in pressure caused by injection of phenylephrine. 3. After administration of the converting enzyme inhibitor (captopril) the mean baroreflex sensitivity of 3 of 4 pregnant ewes increased. 4. It is concluded that high levels of angiotensin II can modify the cardiac baroreceptor reflex response so that the heart rate is inappropriately high for a given systolic pressure and that it reduces the sensitivity of the cardiac baroreflex response to transient changes in arterial pressure.
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45
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Abstract
The previously reported uplift in southern California may have resulted from systematic errors in leveling rather than tectonic activity. Errors are inferred from correlation between changes in elevation and topography at short and long wavelengths. Corrected data show no significant vertical motion except at the time of the San Fernando earthquake. Possible sources of error include inadequate rod calibration and refraction.
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46
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Abstract
Intravenous infusions of angiotensin II were given to conscious sheep. During these infusions, the pressor action of angiotensin was antagonized by concomitant infusion of sodium nitroprusside. Under these conditions, angiotensin produced a dose-dependent tachycardia. This dose-dependent tachycardia was not affected by propranolol and therefore it was not due to an action of angiotensin on sympathoadrenal mechanisms. The dose-dependent tachycardia was reduced by atropine, and abolished by increases in systolic pressure. We conclude that iv infusions of angiotensin cause a central, dose-dependent reduction in vagal tone. This action is normally antagonized by the baroreceptor reflex response to the hypertensive action of angiotensin. Therefore, in those conditions in which endogenous angiotensin production is increased and blood pressure is not elevated (e.g., sodium deficiency and pregnancy), angiotensin may influence heart rate.
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47
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Abstract
A prospective study of the predictive value of pedal venous pressure (PVP) in 100 consecutive cases is discussed. Deep-venous thrombosis is strongly suggested when PVP exceeds 31 cm of saline. The higher the PVP, the more proximal in location is the occluding thrombus.
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48
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Sweet JB, Lee WB, Topping JW. Focal epithelial hyperplasia with sarcoidosis in an American Negro. J Oral Surg 1973; 31:473-6. [PMID: 4512748] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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49
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Lee WB. Medical Amateur Radio Council, Ltd.--"MARCO". Greater St Louis Dent Soc Bull 1970; 41:7. [PMID: 5263490] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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50
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Ross WL, Hayes RL, Lee WB. Oral cytology for the family physician. GP 1969; 40:78-89. [PMID: 5820423] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
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