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Ya Zumeng Gao Zhi Zhang Gang Wang Jianhua Tan Yinghui 《Otolaryngology--head and neck surgery》2006,135(3):458-462
OBJECTIVE: To reduce the incidence of sensory deficits and Frey's syndrome by modifying the traditional superficial parotidectomy. STUDY DESIGN: After raising the skin flap, the parotid gland fascia (PGF) was elevated to form a posterior pedicle fascial flap and then was replaced after the gland removal. The great auricular nerve (GAN) that runs within the PGF was not separated, so both the GAN and the PGF were preserved. Before this modification, the GAN and PGF were examined anatomically. The complication rates in the modified and control groups were compared. RESULTS: 1) The GAN, which runs within the thick and pycnotic PGF, trifurcates into postauricular, preauricular and lobule branches. The modification could be carried out practically based on the anatomy study. 2) Long-term sensory deficit was encountered in 13.3% of the control group, but 0% in the modified one. Frey's syndrome was suffered by 66.7% and 16.7% cases in the control and modified group respectively. The incidence of other complications was not significantly different. CONCLUSION: Our modification is practical. It decreases the complications significantly. EBM rating: B-3b. 相似文献
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PINK1 mutations in sporadic early-onset Parkinson's disease. 总被引:5,自引:0,他引:5
Eng-King Tan Kenneth Yew Eva Chua K Puvan Hui Shen Esther Lee Kim-Yoong Puong Yi Zhao Ratnagopal Pavanni Meng-Cheong Wong Dominic Jamora Deidre de Silva Kyaw-Thu Moe Fung-Peng Woon Yih Yuen Louis Tan 《Movement disorders》2006,21(6):789-793
Pathogenic PINK1 mutations have been described in PARK6-linked Parkinson's disease (PD) patients of Asian origin. However, data on the frequency of PINK1 mutations in sporadic early-onset Parkinson's disease (EOPD) Asian patients are lacking. The objectives of this study were to report the frequency of PINK1 mutations of sporadic EOPD in an Asian cohort comprising of ethnic Chinese, Malays, and Indians, and to highlight a PINK1-positive patient who presented with restless legs symptoms. Eighty consecutive sporadic EOPD patients from the movement disorder clinics of two major tertiary institutions in the country were included. We performed sequence analysis of all the coding and exon-intron junctions of the PINK1 using specific primer sets. In addition, we genotyped polymorphisms detected from the analysis in a group of sporadic PD patients and controls. Three different mutations (two homozygous nonsense and one heterozygous missense) in the putative kinase domain were found in three patients, giving a 3.7% frequency of PINK1 mutations in our EOPD cohort. All the mutations were absent in 200 healthy controls. One patient with a novel homozygous nonsense PINK1 mutation presented unusually with restless legs symptoms. Separately, analysis of the frequency of four PINK1 polymorphisms in a group of sporadic PD and controls did not reveal any significant differences. We highlight a 3.7% frequency of PINK1 mutations in an Asian cohort (ethnic Chinese, Malay, and Indian) of EOPD. The phenotypic spectrum associated with PINK1-positive patients may be wider than previously reported. Polymorphisms of PINK1 do not appear to modulate risk of PD in our population. 相似文献
46.
Outcomes at 3 years of a prospective pilot study of Campath-1H and sirolimus immunosuppression for renal transplantation 总被引:2,自引:0,他引:2
Rolf N. Barth Christina A. Janus Christine A. Lillesand Nancy A. Radke John D. Pirsch Bryan N. Becker Luis A. Fernandez L. Thomas Chin Yolanda T. Becker Jon S. Odorico Anthony M. D''Alessandro Hans W. Sollinger Stuart J. Knechtle 《Transplant international》2006,19(11):885-892
Campath-1H (alemtuzumab) induction was used for renal transplantation in combination with sirolimus as immunosuppression. We previously reported a high (28%) rate of early rejection with this regimen, and now report 3-year outcomes. Twenty-nine patients were recipients of either deceased donor or non-HLA (Human Leukocyte Antigen) identical living donor primary renal allografts. Clinical parameters including infection, malignancy, kidney function, and kidney histology were followed prospectively for 3 years. Three-year cumulative graft and patient survival were 96% and 100%, respectively. Twenty patients were maintained on steroid-free immunosuppressive regimens, and 15 patients were maintained on monotherapy for immunosuppression (12 on sirolimus). No serious infectious complications were observed and two patients developed basal cell skin cancer. The 3-year results of our initial pilot study demonstrate good graft (96%) and patient (100%) outcomes. Campath-1H induction has yielded a high proportion of patients maintained on immunosuppressive monotherapy (57%) without serious infectious- and no malignancy-related complications. The reported regimen yielded novel insights into both Campath-1H and sirolimus therapy in renal transplantation. Because of the higher incidence of early rejection, we recommend a modified strategy of immunosuppression including a brief course of a calcineurin inhibitor. 相似文献
47.
A R Molina H Brasch S T Tan 《Journal of plastic, reconstructive & aesthetic surgery》2006,59(12):1458-1462
One serious complication of neurofibromatosis type 1 (NF1) is the development of malignant peripheral nerve sheath tumours (MPNSTs). These malignancies often develop within pre-existing plexiform neurofibromas and their development is now thought to be associated with both tumour suppressor gene mutations and dysregulated growth factor signalling. Recent work demonstrates that the lifetime risk of malignant transformation is significantly greater than previously thought. Ionising radiation, a long-standing disease, particularly the presence of a large number of plexiform neurofibromas from an early age, are suggested risk factors. We present an NF1 patient who developed an MPNST of the cervical vagus nerve which was successfully treated with surgery. Close monitoring of patients with NF and a high level of suspicion towards rapidly enlarging and painful swellings is merited as these features may signify malignant transformation. Whether a positive history of MPNST in other affected family members predisposes the individual to a higher risk of malignant transformation is unclear. 相似文献
48.
Jonathan Larkin Anne Bost John I Glass Seng-Lai Tan 《Journal of interferon & cytokine research》2006,26(12):854-865
Hepatitis C virus (HCV)-specific impairments in host immunity have been described at multiple levels of the innate and adaptive response, which may lead to viral persistence in the majority of infections. Understanding of HCV-associated immune defects could lead to novel therapeutic advances. Natural killer (NK) cells, the major effector cells of the innate immune system, are functionally impaired in chronic HCV infection. It has been suggested that this phenotype is a result of virus-specific defects in antigen-presenting cells (APCs) that regulate NK cell activity, as normal NK function is restored when they are stimulated ex vivo. In this study, we used human NK cell cytotoxicity assays to evaluate the activation-induced effects of NK cells on the HCV replicon-containing hepatic cells. We found that cytokine-activated NK cells were capable of inducing an HCV-associated, perforin/granzyme-dependent lysis of human hepatoma cells and that this required direct cellular contact and was independent of MHC class I expression levels. In contrast, on removal of cytokine stimulation, NK cells failed to exert any direct cytolytic effect on replicon targets. These findings suggest an important underlying mechanism by which NK cells control HCV infection and, with appropriate understanding of HCV-associated immune defects, could lead to novel therapeutic advances. 相似文献
49.
Diarrhetic shellfish poisoning (DSP) is a serious and globally widespread phytoplankton-related seafood illness. Although DSP is rarely life-threatening, it causes incapacitating diarrhea and vomiting with no known medical treatments. In addition, phytoplankton producing DSP toxins have been identified in temperate coastal waters worldwide, and their numbers may be increasing as a result of coastal eutrophication. The toxic effects of the major DSP toxins, okadaic acid and dinophysistoxin-1 (35-methylokadaic acid), appear to originate from their inhibitory activity against a family of structurally related serine/threonine protein phosphatases (PSPases). In particular, the inhibition of essential PSPases (e.g. PP1 and PP2A) has catastrophic consequences in most eukaryotic cells. Exploiting the potent inhibitory property of the DSP toxins, we have developed an enzyme-based assay (PP2A assay) capable of detecting both okadaic acid and dinophysis- toxin-1 in nanogram amounts. The assay employs purified PP2A, which has an extremely high affinity for both DSP toxins. This provides the PP2A assay with a level of sensitivity comparable to, or surpassing, that of most monoclonal antibody probes. To evaluate the PP2A assay as a means of detecting contaminated shellfish, a series of spike recovery experiments was conducted. The findings from these studies suggest that the PP2A assay has the potential for development into a rapid and relatively simple method for detecting PSPase inhibitors in crude extracts produced from shellfish. 相似文献
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