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1.
Tooth movement and cytokines in gingival crevicular fluid and whole blood in growing and adult subjects. 总被引:1,自引:0,他引:1
Laura R Iwasaki Larry D Crouch Albert Tutor Scott Gibson Navin Hukmani David B Marx Jeffrey C Nickel 《American journal of orthodontics and dentofacial orthopedics》2005,128(4):483-491
INTRODUCTION: Tooth movement has been studied largely with respect to the force required for tipping when pressure distribution varies along the length of the periodontal ligament. But important factors for effective canine translation include the nature and magnitude of applied stress and the patient's cell biology. The purpose of this research was to test 3 hypotheses: (1) the velocity of tooth translation (v(t)) is related to applied stress and growth status, (2) a threshold of stress accounts for the lag phase, and (3) v(t) is correlated with the ratio (AI) of 2 cytokines (IL-1beta, IL-1RA) measured in gingival crevicular fluid (GCF) and stimulated whole blood (SWB). METHODS: Continuous maxillary canine retraction stresses of 13 kPa and 4, 26, or 52 kPa were applied bilaterally in 6 growing and 4 adult subjects for 84 days. Dental models and GCF samples were collected at 1- to 14-day intervals. Cytokines were measured in GCF and SWB cell cultures. RESULTS: V(t) was positively related to stress and was higher in growing subjects (P = .001). It was also related to AI(GCF) in growers (R2= 0.56) and nongrowers (R2= 0.72). Canines moved with 52 kPa showed a lag phase, and postlag phase AI(GCF) was twice that of lag phase AI(GCF). Mean v(t) and associated AI(GCF) during the postlag phase were nearly double the values for canines moved with 13 and 26 kPa. SWB production of cytokines was dose-dependent. For growing subjects, SWB IL-1RA was correlated with v(t) (R = 0.70-0.72), and AI(SWB) and IL-1beta concentrations were correlated with AI(GCF) (R = 0.73-0.78). CONCLUSIONS: V(t) varied with growth status and stresses < or = 52 kPa; stresses of < 52 kPa showed no lag phase; and equivalent stresses yielded subject-dependent differences in v(t), which correlated with cytokines in GCF and SWB. 相似文献
2.
3.
Natural history of the benign breast lump 总被引:2,自引:0,他引:2
J R Sainsbury S Nicholson G K Needham V Wadehra J R Farndon 《The British journal of surgery》1988,75(11):1080-1082
A prospective study of 112 patients with clinically discrete benign breast lumps has shown that 68 per cent of patients experienced resolution of their lumps over a period of up to 2 years. Resolution of both fibro-adenomas and discrete areas of fibro-adenosis was observed. Diagnosis was achieved by clinical examination and fine needle aspiration cytology. Four patients thought clinically to have benign disease were proven by cytology to have a carcinoma, but no patient with a cytopathological diagnosis of benign disease has developed cancer during or subsequent to this study. We recommend that patients under 35 years of age with clinically and cytologically benign breast lumps can be offered the option of non-excision in the reasonable expectation of resolution of their lesion. 相似文献
4.
Nazli Janjua MD Navin Verma MD Ammar Alkawi MD Jawad F. Kirmani MD Adnan I. Qureshi MD 《Journal of neuroimaging》2006,16(3):212-215
Endovascular stent-supported angioplasty is a treatment option for atherosclerotic disease of the cervical internal carotid artery in high-risk patients. The traditional transfemoral approach is not suitable for patients who suffer from common femoral artery or abdominal aorta atheropathy. We report a case of carotid stent deployment using the radial route in a 68-year-old man with type B aortic dissection, having severe right internal carotid artery origin stenosis, presenting with ipsilateral retinal ischemic events. Technical aspects of carotid stenting via the radial approach are described and the related literature is discussed. 相似文献
5.
Dengue is a mosquito-borne viral disease caused by four antigenically distinct serotypes of dengue viruses (DENVs). This disease, which is prevalent in over a hundred tropical and sub-tropical countries of the world, represents a significant global public health problem. A tetravalent dengue vaccine capable of protecting against all four DENV serotypes has been elusive so far. Current efforts are focused on producing a tetravalent vaccine by mixing four monovalent vaccine components. In this work, we have utilized a discrete carboxy-terminal region of the major DENV envelope (E) protein, known as domain III (EDIII), which mediates virus entry into target cells and contains multiple serotype-specific neutralizing epitopes, to create a chimeric tetravalent antigen. This antigen derived by in-frame fusion of the EDIII-encoding sequences of the four DENV serotypes was expressed using a replication-defective recombinant human adenovirus type 5 (rAdV5) vaccine vector. This rAdV5 vector induced cell-mediated immune responses and virus-neutralizing antibodies specific to each of the four DENVs in mice. Interestingly, anti-AdV5 antibodies did not suppress the induction of DENV-specific neutralizing antibodies. We observed that anti-AdV5 antibodies in the sera of immunized mice could promote uptake of a rAdV5-derived reporter vector into U937 cells, suggesting that pre-existing immunity to AdV5 may in fact facilitate the uptake of rAdV5 vectored vaccines into antigen presenting cells. This work presents an alternative approach to developing a single component tetravalent vaccine that bypasses the complexities inherent in the currently adopted four-in-one physical mixture approach. 相似文献
6.
Himu P. Shukla Ralph P. Mason Navin Bansal Peter P. Antich 《Magnetic resonance in medicine》1996,35(6):827-833
A novel noninvasive method of measuring local myocardial oxygen tension (pO2) In the perfused rat heart using 19F MRI is demonstrated. Tissue pO2 was determined on the basis of the 19F spin-lattice relaxation rate (R1) of perflubron (perfluorooctyl bromide) sequestered in the heart after IV infusion of an emulsion. Spectroscopic measurement of R1 was previously used to measure a global weighted average of oxygen status. 19F MRI now provides 3D spatial resolution indicating local cardiac pO2 under normally perfused, globally ischemic, and regionally ischemic conditions. 相似文献
7.
The Cbl family of ubiquitin ligases: critical negative regulators of tyrosine kinase signaling in the immune system 总被引:9,自引:0,他引:9
The Cbl family of proteins are evolutionarily conserved negative regulators of activated tyrosine kinase-coupled receptors. Antigen receptors are prominent targets of negative regulation by the Cbl family members, Cbl and Cbl-b, which proteins function as ubiquitin ligases. Cbl and Cbl-b contain substrate recognition domains that interact specifically with activated protein tyrosine kinases of the Src and Syk/ZAP-70 families. Cbl-mediated ubiquitination of these kinases leads to their degradation, resulting in attenuation of receptor signals. Cbl may also control activation-induced monoubiquitination of antigen receptors, thus facilitating their delivery to lysosomes for subsequent degradation. Finally, the interactions of Cbl proteins with downstream targets of tyrosine kinases, such as PI-3-kinase and Vav, could provide an additional mechanism to attenuate receptor signaling. By targeting multiple components of antigen receptor signaling for degradation, the Cbl protein family provides a critical mechanism to ensure an appropriate immune response. The hyperresponsiveness of Cbl(-/-) and Cbl-b(-/-) lymphocytes and the autoimmune phenotype of Cbl-b(-/-) mice lend strong support for this proposal. The ability to control early receptor signals through regulated protein degradation provides a novel paradigm of immunoregulation. 相似文献
8.
Gabrielle Romain Paolo Strati Ali Rezvan Mohsen Fathi Irfan N. Bandey Jay R T. Adolacion Darren Heeke Ivan Liadi Mario L. Marques-Piubelli Luisa M. Solis Ankit Mahendra Francisco Vega Laurence J.N. Cooper Harjeet Singh Mike Mattie Adrian Bot Sattva S. Neelapu Navin Varadarajan 《The Journal of clinical investigation》2022,132(17)
9.
Sumitra?AroraEmail authorView authors OrcID profile Navin?Mogha Tulsi?Bhardwaj Chitra?Srivastava 《Proceedings of the National Academy of Sciences, India. Section B.》2017,87(4):1229-1236
The solvent extracts of four plants, viz. Polyalthia longifolia (Sonn.) Thw. (PL), Paederia foetida (PF), Limonia acidissima L. (LA) and Balanites aegyptiaca (L.) Del. (BA), from different families, were screened for their antifeedant, insecticidal and insect growth regulatory potential against important crop pests. The solvent extracts, namely methanol, petroleum ether, chloroform and water, of all four plants were tested for their bio-activity against lepidopteran insect pest, Spodoptera litura; and sucking insect pest, L. erysimi (mustard aphid). It was observed that Polyalthia longifolia (methanol extract) exhibited maximum potency with least concentration of 0.1 % (~1080 ppm) to give 50 % antifeedancy, followed by P. longifolia (petroleum ether) with a value of 0.2 % (~2360 ppm) and Limonia acidissima (methanol) and L. acidissima (petroleum ether). The least active compound for antifeedancy was found in the aqueous extract of Balanites aegyptica. Out of 16 plant extracts bio-assayed, methanol showed potential antifeedancy when compared with chloroform, water and petroleum ether extracts. But chloroform and petroleum ether extracts of all four plants gave very promising insecticidal activity against aphids, in comparison to other two extracts. L. acidissima (water), B. aegyptica (methanol), P. longifolia (methanol) and P. foetida (water) did not give any insecticidal activity with 50 % lethal concentration (LC50) up to 0.1 % as maximum concentration. 相似文献
10.
Incremental value of live/real time three‐dimensional transesophageal echocardiography over the two‐dimensional technique in the assessment of a tuberculoma involving the left atrium and appendage 下载免费PDF全文
Tuğba Kemaloğlu Öz M.D. Mahmoud Elsayed M.B.B.Ch Navin C. Nanda M.D. Koray Kalenderoğlu M.D. Şükrü Akyüz M.D. Işıl Atasoy M.D. Altuğ Ösken M.D. Tolga Onuk M.D. Mehmet Eren M.D. 《Echocardiography (Mount Kisco, N.Y.)》2016,33(9):1409-1412
Intracardiac tuberculomas are extremely rare, and cardiac involvement in tuberculosis accounts for only 0.5% of extrapulmonary tuberculosis. We report for the first time incremental value of live/real time three‐dimensional transesophageal echocardiography over two‐dimensional transesophageal echocardiography in the assessment of a tuberculoma involving the left atrium and left atrial appendage. 相似文献