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Chan P, Cheng J. Tu-P8:309 Mechanism for blockade of angiotensin subtype 1 receptors to lower plasma glucose in streptozotocin-induced diabetic rats. ATHEROSCLEROSIS SUPP 2006. [DOI: 10.1016/s1567-5688(06)81012-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Chan P. The basic science of vascular disease A. N. Sidawy, B. E. Sumpio and R. G. DePalma (eds). 285 × 220 mm. Pp. 904. Illustrated 1997. Armonk, New York: Futuru Publishing Company. US$175. Br J Surg 2005. [DOI: 10.1002/bjs.1800840652] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Chan P. Disorders of thrombosis. Hull and G. F. Pineo (eds). 265 × 185 mm. Pp. 447. Illustrated. 1996. Philadelphia, Pennsylvania: W. B. Saunders. £96. Br J Surg 2005. [DOI: 10.1002/bjs.1800830850] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Di Caro A, Castilletti C, Chiappini R, Travaglini D, Girardi E, Chan P, Capobianchi M. CONFRONTO TRA IMMUNOFLUORESCENZA, NEUTRALIZZAZIONE E INDICE DI AVIDITA’ NELLA RILEVAZIONE DELLA RISPOSTA ANTICORPALE ANTI-SARS-CoV. MICROBIOLOGIA MEDICA 2005. [DOI: 10.4081/mm.2005.3608] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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Chan P, Tsang H. Minimizing gain transient dynamics by optimizing the erbium concentration and cavity length of a gain clamped EDFA. OPTICS EXPRESS 2005; 13:7520-7526. [PMID: 19498777 DOI: 10.1364/opex.13.007520] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Erbium doped fiber amplifier (EDFA) gain transient dynamics are studied in the context of their application in optically reconfigurable networks. We address the question of how to design the EDFA in order to minimize the gain transients present in the output signals of the EDFA when the system is optically reconfigured such that the total average input power levels and wavelengths are changed. Both experimental measurements and theoretical simulations show that the amplitude transients depend on the length of the erbium doped fiber (EDF) and the erbium concentration. We show how it may be possible to reduce the gain transients by appropriate design of the EDFA.
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Dinniwell R, Chan P, Haider M, Fyles A, Jaffray D, Milosevic M. 54 Pelvic and inguinal lymphatic target volume delineation: Analysis of the visible human high resolution anatomic data sets. Radiother Oncol 2005. [DOI: 10.1016/s0167-8140(05)80215-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Dinniwell R, Chan P, Lock M, Czarnota G, Bayley A. 55 Limits and limitations of MRI and CT lymphatic target volume delineation: Analysis of the visible human high resolution anatomic data sets. Radiother Oncol 2005. [DOI: 10.1016/s0167-8140(05)80216-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Dinniwell R, Lock M, Chan P, Czarnota G, Wiljer D, Catton P, Kane G. 104 An interactive three-dimensional atlas of nodal topography for radiotherapy treatment planning education. Radiother Oncol 2005. [DOI: 10.1016/s0167-8140(05)80265-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Aderinto J, Brenkel IJ, Chan P. Natural history of fixed flexion deformity following total knee replacement: a prospective five-year study. ACTA ACUST UNITED AC 2005; 87:934-6. [PMID: 15972905 DOI: 10.1302/0301-620x.87b7.15586] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
We investigated fixed flexion deformity (FFD) after total knee replacement (TKR). Data relating to 369 cruciate-retaining unilateral TKRs performed at a single institution were collected prospectively. Fixed flexion was measured pre-operatively and at one week, six months, 18 months, three years and five years after surgery. Using binary logistic regression, pre-operative FFD was a predictor of post-operative FFD > 10 degrees at one week (p = 0.006) and six months (p = 0.003) following surgery. Gender was a predictor at one week (p = 0.0073) with 24% of women showing a FFD > 10 degrees compared with 37% of men. We have shown that a gradual improvement in knee extension can be expected up to three years after surgery in knees with FFD. By this time residual FFD is mild or absent in the majority of patients, including those who had a severe pre-operative FFD.
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Aderinto J, Brenkel IJ, Chan P. Weight change following total hip replacement: A comparison of obese and non-obese patients. Surgeon 2005; 3:269-72, 305. [PMID: 16121773 DOI: 10.1016/s1479-666x(05)80090-3] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
BACKGROUND Weight loss is desirable in obese patients prior to hip replacement but poor mobility secondary to hip dysfunction may limit attempts at weight reduction because of reduced exercise tolerance. METHODS We followed 140 patients prospectively to investigate weight change and functional outcome in obese and non-obese patients following total hip arthroplasty. Weight and the Harris hip score was measured one week prior to surgery and three years post-operatively. RESULTS Fifty nine patients were obese (BMI > or = 30). The mean weight of obese patients increased from 88 kg pre-operatively to 92 kg following surgery (p<0.001). In non-obese patients pre-operative weight was 69 kg and post-operative weight 70 kg (p=0.106). In the obese group 75% of patients gained a mean of 6.77 kg (p<0.001) and 19% of patients lost a mean of 4.8 kg (p<0.01). In the non-obese group, 60% of patients gained a mean of 4.2 kg (p<0.001) and 31% of patients lost an average of 4.7 kg (p<0.001). The mean Harris hip score was 90 in non-obese patients and 85 in obese patients three years post-operatively (p<0.01). CONCLUSION Weight increase is common following total hip replacement despite improved function but the magnitude of weight increase appears to be greater in patients who are obese. Obesity was also associated with lower functional hip scores but the differences were small and unlikely to be of clinical significance.
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Hung LK, Pang KW, Yeung PLC, Cheung L, Wong JMW, Chan P. Active mobilisation after flexor tendon repair: comparison of results following injuries in zone 2 and other zones. J Orthop Surg (Hong Kong) 2005; 13:158-63. [PMID: 16131678 DOI: 10.1177/230949900501300209] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
PURPOSE To prospectively study the role of active mobilisation after flexor tendon repair. METHODS The standard modified Kessler's technique was used to repair 46 digits in 32 patients with flexor tendon injuries. Early active mobilisation of the repaired digit was commenced on the third postoperative day. Range of movement was monitored and recovery from injury in zone 2 was compared with injury in other zones. RESULTS There were 24 and 22 injuries in zone 2 and other zones respectively. The total active motion score of the American Society for Surgery of the Hand was measured. Patients with zone-2 injuries achieved similar results to those with other-zone injuries apart from a 3-week delay in recovery. The final results were good to excellent in 71% and 77% of zone-2 and other-zone cases respectively (p < 0.05). There were 2 ruptures in zone-2 and one rupture in zone-3 repairs (6.5%). CONCLUSION Preliminary results of this study showed that active mobilisation following flexor tendon repair provides comparable clinical results and is as safe as conventional mobilisation programmes although recovery in patients with zone-2 injury was delayed.
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Chao HH, Chen JJ, Chen CH, Lin H, Cheng CF, Lian WS, Chen YL, Juan SH, Liu JC, Liou JY, Chan P, Cheng TH. Inhibition of angiotensin II induced endothelin-1 gene expression by 17-beta-oestradiol in rat cardiac fibroblasts. Heart 2005; 91:664-9. [PMID: 15831659 PMCID: PMC1768884 DOI: 10.1136/hrt.2003.031898] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
OBJECTIVE To examine whether 17-beta-oestradiol (E(2)) may alter angiotensin II (Ang II) induced cell proliferation and to identify the putative underlying signalling pathways in rat cardiac fibroblasts. DESIGN Cultured rat cardiac fibroblasts were preincubated with E(2) then stimulated with Ang II. [(3)H]Thymidine incorporation and endothelin-1 (ET-1) gene expression were examined. The effect of E(2) on Ang II induced NADPH oxidase activity, reactive oxygen species (ROS) formation, and extracellular signal regulated kinase (ERK) phosphorylation were tested to elucidate the intracellular mechanism of E(2) in proliferation and ET-1 gene expression. RESULTS Ang II increased DNA synthesis, which was inhibited with E(2) (1-100 nmol/l). E(2), but not 17-alpha-oestradiol, inhibited Ang II induced ET-1 gene expression as shown by northern blotting and promoter activity assay. This effect was prevented by co-incubation with the oestrogen receptor antagonist ICI 182,780 (1 micromol/l). E(2) also inhibited Ang II increased NADPH oxidase activity, ROS formation, ERK phosphorylation, and activator protein-1 mediated reporter activity. CONCLUSIONS The results suggest that E(2) inhibits Ang II induced cell proliferation and ET-1 gene expression, partially by interfering with the ERK pathway through attenuation of ROS generation. Thus, this study provides important new insight regarding the molecular pathways that may contribute to the proposed beneficial effects of oestrogen on the cardiovascular system.
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Cheng Y, Wong R, Soo YOY, Wong WS, Lee CK, Ng MHL, Chan P, Wong KC, Leung CB, Cheng G. Use of convalescent plasma therapy in SARS patients in Hong Kong. Eur J Clin Microbiol Infect Dis 2005; 24:44-6. [PMID: 15616839 PMCID: PMC7088355 DOI: 10.1007/s10096-004-1271-9] [Citation(s) in RCA: 668] [Impact Index Per Article: 35.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
In order to evaluate the efficacy of convalescent plasma therapy in the treatment of patients with severe acute respiratory syndrome (SARS), 80 SARS patients were given convalescent plasma at Prince of Wales Hospital, Hong Kong, between 20 March and 26 May 2003. Good outcome was defined as discharge by day 22 following the onset of SARS symptoms. Poor outcome was defined as death or hospitalization beyond 22 days. A higher day-22 discharge rate was observed among patients who were given convalescent plasma before day 14 of illness (58.3% vs 15.6%; P<0.001) and among those who were PCR positive and seronegative for coronavirus at the time of plasma infusion (66.7% vs 20%; P=0.001).
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Giannoukas AD, Chan P, Gaines PA. Endoluminal repair of anastomotic false popliteal aneurysm using the Wallgraft endoprosthesis. INT ANGIOL 2005; 24:95-7. [PMID: 15877006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
The aim of this study was to present the endoluminal repair of a false anastomotic popliteal aneurysm on a previous polytetrafluoroethylene (PTFE) above knee bypass using a Wallgraft endoprosthesis. A 53-year-old man who underwent a left femoro-popliteal above knee PTFE bypass 13 years before was admitted with a painful pulsatile mass in the above knee area. Nine months previously he developed sudden pain around the knee extending to the foot associated with coldness and numbness after he was handling some fishing gear in a crouching position for about 1 hour, but this episode spontaneously resolved. Duplex scanning and angiography revealed a 3 x 2.5 cm false aneurysm, which was successfully treated by deploying a Wallgraft endoprosthesis as the patient declined surgical repair. The graft was detected as being occluded on the 3-month follow-up but no further action was taken because the patient experienced only non-limiting claudication and he refused again surgical treatment. Endoluminal repair of perianastomotic false aneurysms in the popliteal artery with Wallgraft endoprosthesis seems feasible and safe, but until its durability is validated in larger series surgical repair remains the treatment of choice.
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Leon L, Giannoukas AD, Dodd D, Chan P, Labropoulos N. Clinical Significance of Superficial Vein Thrombosis. Eur J Vasc Endovasc Surg 2005; 29:10-7. [PMID: 15570265 DOI: 10.1016/j.ejvs.2004.09.021] [Citation(s) in RCA: 81] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
OBJECTIVE To evaluate the clinical implications of superficial thrombophlebitis (STP) including its demographic characteristics, distribution, risk factors, relationship with deep vein thrombosis (DVT), pulmonary embolism (PE), diagnosis and management. METHODS Data were collected from relevant papers using a MEDLINE search and an extensive bibliography review. Studies were considered only when they contained pertinent material to STP. Thirty-seven papers were analysed. RESULTS The diversity of patients and methods used in the different studies made the comparison among them difficult. STP is a common condition with an underestimated prevalence. There are many risk factors associated with STP but the strongest relation was seen with hypercoagulable states. Malignancy may be another important factor but the strength of this association remains unknown. Coexistence with DVT was found in 6-53%. PE occurred in 0-33.3%. Propagation to DVT ranged from 2.6 to 15%. Treatment has not been standardised and may include elastic compression, anti-inflammatory drugs, anticoagulation and surgery. CONCLUSION The limited number of prospective randomised studies on STP does not allow strong recommendations to be given. Although STP most often is perceived as benign, it can coexist with or progress to DVT, and even give rise to PE. It is also associated with hypercoagulability and malignancy.
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Choksy S, Pockley AG, Wajeh YE, Chan P. VEGF and VEGF receptor expression in human chronic critical limb ischaemia. Eur J Vasc Endovasc Surg 2004; 28:660-9. [PMID: 15531204 DOI: 10.1016/j.ejvs.2004.09.001] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/02/2004] [Indexed: 10/26/2022]
Abstract
OBJECTIVE This study quantified endogenous VEGF and VEGF receptor expression in limbs of patients with chronic critical limb ischaemia (CLI). METHODS Skin and muscle biopsies were obtained from the legs of 25 patients undergoing limb amputation for CLI. Samples were obtained at the amputation level (thigh or calf) and, distally, from the foot and in the vicinity of ischaemic ulcers and gangrene. Control biopsies were obtained from patients undergoing amputation for non-arterial reasons or knee arthroplasty (n=7). VEGF protein levels in tissue lysates were measured by ELISA, and VEGF and KDR mRNA levels were determined using quantitative PCR. RESULTS At the amputation level, VEGF protein and VEGF and KDR mRNA levels in CLI limbs were similar to those in controls. In the foot VEGF mRNA in skin (P=0.005) and VEGF protein levels in muscle (P=0.02) were elevated compared to levels in a proximal biopsy from the same limb. VEGF and KDR mRNA levels in the vicinity of gangrene/ulcers (VEGF P=0.01, KDR P=0.03) also were elevated. CONCLUSIONS VEGF expression is not deficient in CLI. Indeed, it is elevated at distal sites in the ischaemic limb. These findings question the rationale for VEGF supplementation in CLI.
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El Wajeh Y, Giannoukas AD, Gulliford CJ, Suvarna SK, Chan P. Saphenofemoral Venous Channels Associated with Recurrent Varicose Veins are not Neovascular. Eur J Vasc Endovasc Surg 2004; 28:590-4. [PMID: 15531192 DOI: 10.1016/j.ejvs.2004.09.011] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/13/2004] [Indexed: 10/26/2022]
Abstract
BACKGROUND Recurrence of varicose veins after apparently adequate surgery is common. Neovascularisation, the formation of new vascular channels between a venous surgery site and new varicosities, is thought to be an important cause of recurrence. The aim of this study was to provide histological evidence of the 'neovascularisation'process. METHOD Tissue samples from the region of the previously ligated saphenofemoral junction (SFJ) were taken from 14 limbs with recurrent varicose veins and from nine control limbs. Tissue samples were analysed histologically for overall vascularity, and the presence of intimal circular fibrosis, intimal eccentric fibrosis, medial thickened elastosis, and thrombosis in the microscopic thin walled vessels within the tissue. The same samples were analysed immunohistoligically for S100, a neural marker, and Ki-67 (Mib 1), a marker of endothelial proliferation. Absent S100 and positive Ki-67 were considered as evidence of new vessels. RESULT No significant difference was found between the venous recurrence and control groups in respect to histological features. S100 positive nerve fibrils were seen associated with dilated venous channels in the majority of both redo and control groups (p=1, Fisher's exact test). Only one section stained positively with Ki-67 (Mib1) in a single vascular channel for a few endothelial cells. The remaining control and redo cases were negative for Mib 1 (p=1, Fisher's exact test). CONCLUSION We found little evidence of neovascularisation associated with recurrent varicose veins in the saphenofemoral region. The venous channels that develop at the previously ligated SFJ may represent adaptive dilatation of pre-existing venous channels (vascular remodelling), probably in response to abnormal haemodynamic forces.
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Al-Assiri M, Chan P. Incidental discovery of emphysematous cystitis with rapid resolution in a patient presenting with acute pancreatitis. ScientificWorldJournal 2004; 4:881-4. [PMID: 15517096 PMCID: PMC5956443 DOI: 10.1100/tsw.2004.138] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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Soo YOY, Cheng Y, Wong R, Hui DS, Lee CK, Tsang KKS, Ng MHL, Chan P, Cheng G, Sung JJY. Retrospective comparison of convalescent plasma with continuing high-dose methylprednisolone treatment in SARS patients. Clin Microbiol Infect 2004; 10:676-8. [PMID: 15214887 PMCID: PMC7129386 DOI: 10.1111/j.1469-0691.2004.00956.x] [Citation(s) in RCA: 274] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Treatment of severe acute respiratory syndrome (SARS) is experimental, and the effectiveness of ribavirin–steroid therapy is unclear. Forty SARS patients with progressive disease after ribavirin treatment and 1.5 g of pulsed methylprednisolone were given either convalescent plasma (n = 19) or further pulsed methylprednisolone (n = 21) in a retrospective non‐randomised study. Good clinical outcome was defined as discharge by day 22 following the onset of symptoms. Convalescent plasma was obtained from recovered patients after informed consent. Patients in the plasma group had a shorter hospital stay (p 0.001) and lower mortality (p 0.049) than the comparator group. No immediate adverse effects were observed following plasma infusion.
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Teitel JM, Robillard P, Rock GA, Wong-Rieger D, Lai ES, Chan P. A review of research related to blood transfusion in Canada, 2000-2002. Transfus Med 2004; 14:195-203. [PMID: 15180811 DOI: 10.1111/j.0958-7578.2004.00512.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The former National Blood Safety Council undertook a comprehensive review of blood transfusion research in Canada for the years 2000 through 2002. Data were acquired by direct contact with agencies which support such research and by searches of the relevant websites. Total grant support increased markedly over the 3-year period, from 4.1 million dollars to 18.5 million dollars. Publicly funded granting agencies, biopharmaceutical companies, the blood services and the province of Ontario were major supporters. Much smaller amounts were granted from charitable organizations. Clinical research attracted the majority of the funding, although a larger number of projects were basic science in nature. Most research was carried out in the provinces of Ontario, Québec and British Columbia. Although we have not assessed the productivity of blood-related research, it appears that substantial amounts of funding were allocated to these projects between 2000 and 2002. These data may provide a helpful perspective to investigators in transfusion medicine elsewhere, who may also be assessing the relative priority given to this field of research in their own countries.
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Liang CL, Hung KS, Park N, Chan P, Juo SHH. Comparison of the handheld Retinomax K-Plus2 and on-table autokeratometers in children with and without cycloplegia. J Cataract Refract Surg 2004; 30:669-74. [PMID: 15050266 DOI: 10.1016/s0886-3350(03)00662-x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/15/2003] [Indexed: 11/21/2022]
Abstract
PURPOSE To compare the keratometry measurements in children by the handheld Nikon Retinomax K-Plus2 (Rmax) and the on-table Topcon KR8100 autokeratometers and evaluate the degree of agreement in the 2 instruments between children with and without cycloplegia. SETTING Department of Ophthalmology, Kaohsiung Municipal United Hospital, and Chang-Gung Memorial Hospital, Kaohsiung, Taiwan. METHODS The first cohort comprised 61 children who were consecutively collected in the pediatric ophthalmology clinic. The keratometry was measured under cycloplegia. The second cohort included 156 school children who received routine vision screening without cycloplegia. The horizontal and vertical keratometry data were measured by both instruments. The mean bias and agreement between the 2 types of measurements were evaluated. RESULTS Both horizontal and vertical keratometry data from the Rmax were systemically and mildly lower than the data from the Topcon. The mean keratometric difference in the 2 types of instruments was minimal and clinically acceptable: 72% to 85% was within +/-0.5 diopter. The agreement of measured data in the children without cycloplegia was higher than that in the children with cycloplegia. CONCLUSIONS The handheld Retinomax provided comparable data to that of the conventional on-table Topcon. It is useful in the clinic to measure keratometry in children and therefore may offer a convenient tool for assessing corneal curvature for fitting contact lenses or for implanting intraocular lenses in young children.
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Chang SKY, Chan P. Recurrent appendicitis as a cause of recurrent right iliac fossa pain. Singapore Med J 2004; 45:6-8. [PMID: 14976575] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/29/2023]
Abstract
Recurrent appendicitis is defined when patients with recurring similar right iliac fossa pain had acute appendicitis confirmed at the time of operation and the pain completely subsided after surgery. We conducted a retrospective study on our patients with appendicitis. There were 290 patients with appendicitis over a two-year period and 33 patients (11%) had reported recurring pain prior to the presentation. Majority had one prior episode but 15% had multiple episodes of right iliac fossa pain. Fifty-eight percent of the episode occur within six months of the presentation. We conclude that recurrent appendicitis should be considered as a differential diagnosis in patients with recurrent right iliac fossa pain.
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Liang CL, Hung KS, Park N, Chan P, Juo SHH. Comparison of measurements of refractive errors between the hand-held Retinomax and on-table autorefractors in cyclopleged and noncyclopleged children. Am J Ophthalmol 2003; 136:1120-8. [PMID: 14644224 DOI: 10.1016/s0002-9394(03)00789-x] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
PURPOSE To compare the measurement of refractive errors (sphere, cylinder, and axis) between the hand-held Retinomax and on-table Topcon autorefractors in cyclopleged and noncyclopleged young children. The average bias and measurement agreement were assessed. DESIGN Observational cross-sectional study. METHODS The study included 114 cyclopleged and 156 noncyclopleged young children. The mean difference between the two methods and the 95% limits of agreement were calculated to evaluate the average bias. Two types of analyses were conducted to assess the degree of agreement. First, the proportion of the absolute mean differences was presented in different ranges (<or=0.25, 0.25-0.5, 0.5-0.75, 0.75-1.0, and >1.0 diopters for sphere and cylinder; 0-10, 11-20 and >20 degrees for axis). Second, the paired t test was conducted to evaluate the consistency of two types of measurements. RESULTS The data by the Retinomax had mild bias (0.59 diopters) toward a lower sphere data under noncycloplegia but no bias under cycloplegia. For cylinder and axis, there was either no bias or clinically acceptable bias (0.02-0.13 diopters for cylinder and 2-7 degrees for axis) regardless of cycloplegia. Besides the sphere data under noncycloplegia, in general 90% of the mean differences of sphere and cylinder were within 0.5 diopters. More than 97% of the difference in axis under cycloplegia and 68% under noncycloplegia were within 20 degrees. After adjusting for mild bias, the paired t test showed very consistent results. CONCLUSIONS The data by the Retinomax were consistent with those by the Topcon. The Retinomax is a useful instrument to screen refractive errors in young children.
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Hong HL, Ton TV, Devereux TR, Moomaw C, Clayton N, Chan P, Dunnick JK, Sills RC. Chemical-specific alterations in ras, p53, and beta-catenin genes in hemangiosarcomas from B6C3F1 mice exposed to o-nitrotoluene or riddelliine for 2 years. Toxicol Appl Pharmacol 2003; 191:227-34. [PMID: 13678655 DOI: 10.1016/s0041-008x(03)00165-0] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The most prominent neoplastic lesions in mice in the 2-year studies of o-nitrotoluene and riddelliine were hemangiosarcomas. Fifteen o-nitrotoluene-induced hemangiosarcomas of the skeletal muscle, subcutaneous tissue, and mesentery; 12 riddelliine-induced hemangiosarcomas of the liver; and 15 spontaneous subcutaneous hemangiosarcomas were examined for genetic alterations in ras, p53, and beta-catenin genes. Mutations in at least one of these genes were identified in 13 of 15 (87%) of the o-nitrotoluene-induced hemangiosarcomas with missense mutations in p53 exons 5-8 detected in 11 of 15 (73%) of these neoplasms. Seven of 15 (47%) hemangiosarcomas from mice exposed to o-nitrotoluene had deletions at exon 2 splice sites or smaller deletions in the beta-catenin gene. K-ras mutation was detected in only 1 of the 15 (7%) o-nitrotoluene-induced hemangiosarcomas. In contrast to the o-nitrotoluene study, 7/12 (58%) riddelliine-induced hemangiosarcomas had K-ras codon 12 GTT mutations and, when screened by immunohistochemistry, 9/12 (75%) had strong staining for the p53 protein in malignant endothelial cells, the cells of origin of hemangiosarcomas. Riddelliine-induced hemangiosarcomas were negative for the beta-catenin protein. Spontaneous hemangiosarcomas from control mice lacked both p53 and beta-catenin protein expression and ras mutations. Our data indicated that p53 and beta-catenin mutations in the o-nitrotoluene-induced hemangiosarcomas and K-ras mutations and p53 protein expression in riddelliine-induced hemangiosarcomas most likely occurred as a result of the genotoxic effects of these chemicals. It also suggests that these mutations play a role in the pathogenesis of the respective hemangiosarcomas in B6C3F1(1) mice.
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Chen R, Gosavi NS, Langston JW, Chan P. Parkin mutations are rare in patients with young-onset parkinsonism in a US population. Parkinsonism Relat Disord 2003; 9:309-12. [PMID: 12781599 DOI: 10.1016/s1353-8020(03)00018-x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Parkin mutations have been associated with an autosomal recessive-juvenile parkinsonism, but it is unclear how common such patients are in a US based clinic population. In this study, we screened for parkin gene mutations in a clinic-based series of 27 consecutive patients in the US with typical parkinsonism beginning before the age of 50 years. Two patients began the disease before the age of 30 years. Among the 27 patients screened, only one patient, whose disease began at the age of 24 years, was found to harbor a parkin mutation (a 40 bp deletion in exon 3). In addition, we also identified four new polymorphisms in the open reading frames of the parkin gene in this population. Our results suggest parkinsonism due to mutations in the parkin gene is extremely rare in the US population when the disease begins over the age of 30.
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