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Akio Tanaka Motoyoshi Okamoto Dai Yoshizawa Shigeru Ito Patricia González Alva Fumio Ide Kaoru Kusama 《Journal of oral pathology & medicine》2007,36(7):400-404
BACKGROUND: Although it has been reported that ghost cells are present in odontomas, the generation mechanism of these cells is unclear. To evaluate the presence of ghost cells and involvement of the Wnt signaling pathway, we examined the expression of hard keratins, beta-catenin and Lef-1 in odontomas. METHODS: Sixty-nine cases of odontoma were examined immunohistochemically with the use of antibodies against human hair proteins, beta-catenin and Lef-1. RESULTS: Expression of hard keratins was found only in the cytoplasm of ghost cells in 46 (66.7%) of the 69 odontomas. Compound odontomas (78.8%) showed a higher incidence of ghost cells than complex odontomas (29.4%). Histopathologically, ghost cells were found within odontogenic epithelium adjacent to immature enamel and in the centre of Liesegang-ring-like calcified materials. Expression of beta-catenin and Lef-1 was observed in the cytoplasm and nucleus of odontogenic epithelial cells adjacent to the ghost cells in immature odontomas. CONCLUSION: These findings suggest that odontoma is a hard keratin-expressing tumor-like lesion, and that the Wnt signaling pathway may be involved in the formation of ghost cells in odontomas. 相似文献
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目的 真核表达人呼吸道合胞病毒(human respiratory syncytial virus,SV)融合蛋白(fusion protein,),并完成蛋白纯化及纯度测定.方法 根据编码F蛋白的基因序列设计引物,CR方法扩增出3'端带His标签的F基因序列,克隆入pGEM-T-easy载体,经核酸序列分析后,进一步克隆到pcDNA3.1( )真核表达载体,限制性内切酶鉴定,用脂质体Lipofectamine2000转染COS-7细胞,2 h后再用Westem blot检测目的蛋白的表达.Ni柱亲和层析纯化COS-7细胞表达的F蛋白,高效毛细管电泳分析纯化后蛋白纯度.结果 核酸序列分析证实获得带His标签的RSV F基因序列,没有发生无义突变.转染COS-7细胞后,利用Western blot方法检测到F蛋白的特异性条带,纯度达99%以上.结论 初步建立了真核表达RSV F蛋白的纯化方法,为进一步优化RSV F蛋白制备条件及单克隆抗体及诊断试剂等研究奠定了基础. 相似文献
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Nonulcerative penile mass lesions are rare. Pathological diagnosis of these lesions would traditionally be a biopsy. We report two such primary penile lesions which were diagnosed by fine-needle aspiration cytology (FNAC). Both lesions were present in the shaft and were diagnosed as squamous cell carcinoma (SCC). The first patient had a recurrence on the penile stump of partial amputation without any ulceration. The second had a primary urethral carcinoma on the terminal penile shaft infiltrating the corpora cavernosa dorsally. Open biopsies were avoided in both cases. FNAC was associated with very little and tolerable discomfort. There were no complications. The aspirate yield was sufficient for cytological diagnosis. FNAC of nonulcerated penile lesions is safe, well tolerated, and capable of providing a cytological diagnosis. Hence, it is a very useful outpatient procedure and could be the procedure of choice for diagnosis. 相似文献
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Alva O. Ferdinand Marvellous A. Akinlotan Timothy Callaghan Samuel D. Towne Jr Jane Bolin 《Journal of diabetes and its complications》2019,33(5):350-355
Aims
Despite advancements in the diagnosis and treatment of diabetes in the U.S., place-based disparities still exist. The purpose of this study is to determine place-based and other individual-level variations in diabetes-related hospital deaths.Methods
A pooled cross-sectional study of the 2009–2015 National Inpatient Sample was conducted to examine the odds of a diabetes-related hospital death. The main predictors were rurality and census region. Individual-level socio-demographic factors were also examined.Results
Approximately 1.5% (n?=?147,069) of diabetes-related hospitalizations resulted in death. In multivariable analysis, the odds of diabetes-related hospital deaths increased across the urban-rural continuum, except for large fringe metropolitan areas, with the highest odds of such deaths occurring among residents of micropolitan (OR?=?1.16, 95% C.I.?=?1.14, 1.18) and noncore areas (OR?=?1.21, 95% C.I.?=?1.19, 1.24). Compared to residents of the Northeast, residents in the South, West and Midwest regions were significantly more likely to experience a diabetes-related hospital death. Asian or Pacific Islanders, Medicaid-covered patients and the uninsured were also more likely to die during a diabetes-related hospitalization.Conclusions
Place-based disparities in diabetes-related hospital deaths exist. Targeted focus should be placed on the control of diabetic complications in the South, West and Midwest census regions, and among rural residents. 相似文献7.
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Samus QM Rosenblatt A Steele C Baker A Harper M Brandt J Mayer L Rabins PV Lyketsos CG 《The Gerontologist》2005,(1):19-26
PURPOSE: We conducted this study to determine whether neuropsychiatric symptoms and environmental characteristics are associated with quality of life in assisted living residents with dementia. DESIGN AND METHODS: We used a cross-sectional study of 134 residents from 22 facilities and employed the Alzheimer's Disease-Related Quality of Life Scale and the Neuropsychiatric Inventory. A scale was developed to capture the homelike climate of each facility. Linear regression analyses were used to estimate the relationship of neuropsychiatric symptoms and homelike climate with quality of life, controlling for sociodemographics, cognition, functional dependence, and physical health. Exploratory analyses and graphical techniques were employed to test for environmental-level moderating effects. RESULTS: Agitation, depression, apathy, and irritability were significant predictors of quality of life, explaining 29% of the variance. Neither facility size nor homelike environment was significantly associated with quality of life in univariate analyses. Size of facility moderated the relationship between agitation and quality of life. IMPLICATIONS: Neuropsychiatric symptoms impair quality of life in residents with dementia. Further research should investigate the role of other environmental aspects. 相似文献
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Alva O. Ferdinand Nir Menachemi Bisakha Sen Justin L. Blackburn Michael Morrisey Leonard Nelson 《American journal of public health》2014,104(8):1370-1377
Using a panel study design, we examined the effects of different types of texting bans on motor vehicular fatalities.We used the Fatality Analysis Reporting System and a difference-in-differences approach to examine the incidence of fatal crashes in 2000 through 2010 in 48 US states with and without texting bans. Age cohorts were constructed to examine the impact of these bans on age-specific traffic fatalities.Primarily enforced laws banning all drivers from texting were significantly associated with a 3% reduction in traffic fatalities in all age groups, and those banning only young drivers from texting had the greatest impact on reducing deaths among those aged 15 to 21 years. Secondarily enforced restrictions were not associated with traffic fatality reductions in any of our analyses.Motor vehicle safety has been described as one of the 10 great public health achievements in the United States in the past decade,1 with car manufacturers and highway engineers making significant improvements to car and roadway safety features.2 Despite these improvements, traffic fatalities remain one of the leading causes of death in the United States,3 with an estimated 32 788 such deaths in 2010.4 Thus, road traffic fatalities continue to be a significant public health concern,5,6 garnering much attention from state lawmakers.In an effort to reduce motor vehicle fatalities, states have enacted restrictions on drunk driving, implemented graduated driver’s license programs, and mandated seatbelt use and special licensing procedures for older adults. Most recently, states have focused on restricting texting while driving.7–9 Generally, states define texting as reading, manual composition, or sending of electronic communications—text messages, instant messages, or e-mails—via a portable electronic device. Portable electronic devices include mobile (i.e., cellular) phones, personal digital assistants, and laptop computers. Texting while driving is a serious threat to road safety,10–13 given that research has shown that mobile phone use is associated with impaired following distance,14 improper lane position,11,15 longer reaction times,11,14,16 and crashes,11,17 which can all lead to significant adverse public health outcomes, including death.18 Unlike talking on a mobile phone while driving, texting poses a unique threat in that it requires drivers to take their eyes off the road for several seconds at a time.14Our current understanding of the impact of texting laws on driving outcomes is limited. To our knowledge, 2 studies have empirically examined the impact of texting laws on adverse motor vehicle outcomes. The first was published by the Highway Loss Data Institute.19 It examined the relationship of collision claim frequency and texting bans in just 4 states (CA, LA, MN, and WA). The authors found that texting bans were associated with increased collision claims. They speculated that this increase might be due to drivers hiding their phones from view to avoid fines and, in so doing, taking their eyes off the road more than they did before the bans. More recently, Abouk and Adams20 published the first national-level study of texting bans’ impacts on traffic fatalities. They examined the impact of texting-while-driving bans on the occurrence of only single-vehicle, single-occupant accidents between 2007 and 2010. Their findings indicated that stronger bans that are applied to all drivers were associated with decreases in single-vehicle, single-occupant accidents.The purpose of this study is to add to the knowledge base concerning the effectiveness of texting laws, particularly by considering the varying stringency levels of these laws. Texting bans can be secondarily enforced (i.e., an officer must have another reason to stop a vehicle before citing a driver for texting while driving) or primarily enforced (i.e., an officer does not have to have another reason for stopping a vehicle). Furthermore, some states ban texting among learner’s permit holders, and some ban texting among all those aged 18 years, 21 years, or younger, and still other states ban all drivers from texting. Some states have no texting laws at all. We consider the impact of each of these policy nuances on traffic fatalities in 48 states over an 11-year period. Moreover, given that younger individuals are more likely to text while driving,21 we examine the impact of texting laws on age-specific traffic fatalities. Overall, this study will be of interest to policymakers, law enforcement personnel, and other stakeholders interested in improving roadway safety and, by extension, public health. 相似文献
10.
Calixto‐Hope G. Lucas Javier E. Villanueva‐Meyer Nicholas Whipple Nancy Ann Oberheim Bush Tabitha Cooney Susan Chang Michael McDermott Mitchel Berger Elaine Cham Peter P. Sun Angelica Putnam Hong Zhou Robert Bollo Samuel Cheshier Matthew M. Poppe Kar‐Ming Fung Sarah Sung Chad Glenn Xuemo Fan Serguei Bannykh Jethro Hu Moise Danielpour Rong Li Elizabeth Alva James Johnston Jessica Van Ziffle Courtney Onodera Patrick Devine James P. Grenert Julieann C. Lee Melike Pekmezci Tarik Tihan Andrew W. Bollen Arie Perry David A. Solomon 《Brain pathology (Zurich, Switzerland)》2020,30(3):479-494
“Myxoid glioneuronal tumor, PDGFRA p.K385‐mutant” is a recently described tumor entity of the central nervous system with a predilection for origin in the septum pellucidum and a defining dinucleotide mutation at codon 385 of the PDGFRA oncogene replacing lysine with either leucine or isoleucine (p.K385L/I). Clinical outcomes and optimal treatment for this new tumor entity have yet to be defined. Here, we report a comprehensive clinical, radiologic, and histopathologic assessment of eight cases. In addition to its stereotypic location in the septum pellucidum, we identify that this tumor can also occur in the corpus callosum and periventricular white matter of the lateral ventricle. Tumors centered in the septum pellucidum uniformly were associated with obstructive hydrocephalus, whereas tumors centered in the corpus callosum and periventricular white matter did not demonstrate hydrocephalus. While multiple patients were found to have ventricular dissemination or local recurrence/progression, all patients in this series remain alive at last clinical follow‐up despite only biopsy or subtotal resection without adjuvant therapy in most cases. Our study further supports “myxoid glioneuronal tumor, PDGFRA p.K385‐mutant” as a distinct CNS tumor entity and expands the spectrum of clinicopathologic and radiologic features of this neoplasm. 相似文献