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Nanofeatured surfaces in dental implants: contemporary insights and impending challenges.
Dental implant therapy, established as standard-of-care nearly three decades ago with the advent of microrough titanium surfaces, revolutionized clinical outcomes through enhanced osseointegration. However, despite this pivotal advancement, challenges persist, including prolonged healing times, restricted clinical indications, plateauing success rates, and a notable incidence of peri-implantitis. This review explores the biological merits and constraints of microrough surfaces and evaluates the current landscape of nanofeatured dental implant surfaces, aiming to illuminate strategies for addressing existing impediments in implant therapy. Currently available nanofeatured dental implants incorporated nano-structures onto their predecessor microrough surfaces. While nanofeature integration into microrough surfaces demonstrates potential for enhancing early-stage osseointegration, it falls short of surpassing its predecessors in terms of osseointegration capacity. This discrepancy may be attributed, in part, to the inherent dichotomy kinetics of osteoblasts, wherein increased surface roughness by nanofeatures enhances osteoblast differentiation but concomitantly impedes cell attachment and proliferation. We also showcase a controllable, hybrid micro-nano titanium model surface and contrast it with commercially-available nanofeatured surfaces. Unlike the commercial nanofeatured surfaces, the controllable micro-nano hybrid surface exhibits superior potential for enhancing both cell differentiation and proliferation. Hence, present nanofeatured dental implants represent an evolutionary step from conventional microrough implants, yet they presently lack transformative capacity to surmount existing limitations. Further research and development endeavors are imperative to devise optimized surfaces rooted in fundamental science, thereby propelling technological progress in the field
Bcl-2 genes regulate noise-induced hearing loss
Proteins of the Bcl-2 family have been implicated in control of apoptotic pathways modulating neuronal cell death, including noise-induced hearing loss. In this study, we assessed the expressions of anti- and proapoptotic Bcl-2 genes, represented by Bcl-xL and Bak following noise exposures, which yielded temporary threshold shift (TTS) or permanent threshold shift (PTS). Auditory brainstem responses (ABRs) were assessed at 4, 8, and 16 kHz before exposure and on days 1, 3, 7, and 10 following exposure to 100 dB SPL, 4 kHz OBN, 1 hr (TTS) or 120 dB SPL, 4 kHz OBN, 5 hr (PTS). On day 10, subjects were euthanized. ABR thresholds increased following both exposures, fully recovered following the TTS exposure, and showed a 22.6 dB (4 kHz), 42.5 dB (8 kHz), and 44.9 dB (16 kHz) mean shift on day 10 following the PTS exposure. PTS was accompanied by outer hair cell loss progressing epically and basally from the 4-kHz region. Additional animals were euthanized for immunohistochemical assessment. BcL-xL was robustly expressed in outer hair cells following TTS exposure, whereas Bak was expressed following PTS exposure. These results indicate an important role of the Bcl-2 family proteins in regulating sensory cell survival or death following intense noise. Bcl-xL plays an essential role in prevention of sensory cell death following TTS levels of noise, and PTS exposure provokes the expression of Bak and, with that, cell death. © 2007 Wiley-Liss, Inc.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/58028/1/21533_ftp.pd
シロイヌナズナ熱ショック転写因子HsfA2の機能解析
取得学位:博士(理学),学位授与番号:博甲第939号,学位授与年月日:平成19年3月31
An experimental vegetation management for increasing forest floor plant species deiversity of the Japanese alder swamp
鳥取県日野郡日南町神戸上のハンノキ沼沢林は中国・近畿地方で最大規模であり, 鳥取県の天然記念物および自然環境保全地域に指定される貴重な湿地生態系である. しかし, ハンノキ林床では, カサスゲ(Carex dispalata)・ミゾソバ(Persicarita thunbergii)などの高茎湿地草本や低木が繁茂し, 湿性草本群落の種多様性の低下が起きている. そこで本研究では, 湿性草本の種多様性の向上を目的として, カサスゲなどの生育を抑制するための植生管理実験を行うとともに, 表土撒きだし実験による湿性植生の再生の可能を評価した. その結果, 刈取りは低木抑制に,耕起はカサスゲの抑制にそれぞれ一定の効果があることが認められた. また, 表土撒き出し実験では地上部で確認できなかった湿性草本種が出現した. しかし, 高木層による被陰や湿原の富栄養化など林床植生の管理だけでは解決できない問題があり, ハンノキの伐採・萌芽更新などの抜本的な対策が必要であると認められた.
Emphysematous Cystitis in a Patient with Type 2 Diabetes Mellitus
A 62-year-old woman with a history of poorly controlled type 2 diabetes mellitus was admitted to our hospital with a 3-week history of mild fever, vomiting, and anorexia. Abdominal computed tomography (CT) showed bilateral hydronephrosis and gas accumulation in the urinary bladder wall and left ureter. Laboratory tests showed leukocytosis and elevated C-reactive protein level. Urine culture showed heavy growth of Escherichia coli. The final diagnosis was emphysematous cystitis. The patient was treated with systemic antibiotics and drainage using a urethral catheter. The clinical and radiographic findings resolved rapidly, and she was discharged from the hospital on day 28. Emphysematous cystitis is a relatively rare urinary tract infection associated with gas formation, and has the potential for a serious outcome if untreated. Early detection by imaging studies such as CT is important in providing prompt treatment and favorable clinical outcome
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