• 제목/요약/키워드: retinal

검색결과 467건 처리시간 0.027초

안구의 굴절능 조절을 고려한 수정된 Navarro 정밀모형안의 시성능 분석 (Visual Performances of the Corrected Navarro Accommodation-Dependent Finite Model Eye)

  • 최가을;송석호;김상기
    • 한국광학회지
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    • 제18권5호
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    • pp.337-344
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    • 2007
  • 모형안은 안구의 굴절력 교정 수술이나 콘택트렌즈, 안경 등 시력 보정을 위한 기구를 설계하는 등, 다양한 목적아래서 안구의 시성능을 최적모델링 하기 위해 발전해 왔다. 특히, 안구의 가변적인 굴절능 조절 과정을 내포하는 모형안을 세우고, 환경변화에 따른 모형안의 광학 성능을 정확하게 모델링하는 것은 매우 중요하다. 본 연구는 사람 안구가 단계적으로 굴절능 조절을 행할 때 기존의 해부학적 광학형상 변화를 포함하고 안구의 파면수차와 조절반응을 고려한 모형안을 제시하였다. 본 연구에서 제시된 모형안은 조절자극의 세기에 따른 조절반응 부족량, 3차와 4차 수차, 변조전달함수, 시력 등이 제시되었으며, 그 모형안을 바탕으로 계산한 결과 값은 실제 안구에서 측정한 값들을 만족하였다. 본 연구에서 제안된 모형안은 조절의 단계적 변화에 따른 안구의 광학적 성능과 변조저달 함수의 계산, 사람 눈의 시성능 변화를 보다 정확하게 예측하는데 좋은 도구를 제공할 것이다.

소세포성 폐암과 연관된 망막증 1예 (A Case of Cancer Associated Retinopathy with Small Cell Lung Carcinoma)

  • 임성민;배종오;조상건;강상구;이은영;김성국;김영;곽진영;김귀완
    • Tuberculosis and Respiratory Diseases
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    • 제59권6호
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    • pp.679-683
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    • 2005
  • 저자들은 시야 결손 등의 시력 변화를 주 증상으로 내원한 환자에서 소세포 폐암과 이로 인한 부종양성증후군으로 동반된 암 관련 망막증을 진단하고 항암화학요법을 시행하여, 원발 병변의 부분 관해 보였으나, 시야 결손은 회복되지 않았던 1예를 경험하였기에 문헌 고찰과 함께 보고 하는 바이다.

Effects of Various Laser Wavelengths and Power Densities on the Ocular Damage in Pigmented Rats

  • Chung, Phil-Sang;Shin, Jang-In;Chang, Moo-Hwan;Chang, So-Young;Kang, Jung-Wook;Hwang, Hee-Jun;Ahn, Jin-Chul
    • 대한의생명과학회지
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    • 제14권3호
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    • pp.173-178
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    • 2008
  • With the widespread use of laser in medical and industrial settings, the incidence of laser injury to the ocular continues to grow among workers involved in handling lasers. The aim of this study is to compare ocular damages after irradiation with various laser wavelengths and power density. Ocular of pigmented rats was irradiated with $CO_2$ laser, 1064 nm Nd:YAG laser, and 532 nm diode laser. We observed damage of cornea, lens, and retina using slit lamp microscope and funduscopy. H&E staining of histopathology were applied to study the specimens. The higher exposure ($200mW/cm^2$, 10 sec) with $CO_2$ laser resulted in severe damage at the cornea. For the 1064 nm Nd:YAG laser, the higher exposure than $10mW/cm^2$ (10 sec) resulted in damage at the cornea and lens. Further, with the 532 nm diode laser, retinal lesions were induced when $10mW/cm^2$ (0.25 sec) was delivered to the eye. Theses results suggest that the ocular damages are different from various laser wavelength and power density.

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A case of McKusick-Kaufman syndrome

  • Son, Se-Hyung;Kim, Yoon-Joo;Kim, Eun-Sun;Kim, Ee-Kyung;Kim, Han-Suk;Kim, Beyong-Il;Choi, Jung-Hwan
    • Clinical and Experimental Pediatrics
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    • 제54권5호
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    • pp.219-223
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    • 2011
  • McKusick-Kaufman syndrome (MKS) is an autosomal recessive multiple malformation syndrome characterized by hydrometrocolpos (HMC) and postaxial polydactyly (PAP). We report a case of a female child with MKS who was transferred to the neonatal intensive care unit of Seoul National University Children's Hospital on her 15th day of life for further evaluation and management of an abdominal cystic mass. She underwent abdominal sonography, magnetic resonance imaging, genitography and cystoscopy which confirmed HMC with a transverse vaginal septum. X-rays of the hand and foot showed bony fusion of the left third and fourth metacarpal bones, right fourth dysplastic metacarpal bone and phalanx, right PAP and hypoplastic left foot with left fourth and fifth dysplastic metatarsal bones. In addition, she had soft palate cleft, mild hydronephroses of both kidneys, hypoplastic right kidney with ectopic location and mild rotation, uterine didelphys with transverse vaginal septum and low-type imperforated anus. She was temporarily treated with ultrasound-guided transurethral aspiration of the HMC. Our patient with HMC and PAP was diagnosed with MKS because she has two typical abnormality of MKS and she has no definite complications of retinal disease, learning disability, obesity and renal failure that develop in Bardet-Biedl syndrome, but not in MKS until 33 months of age. Here, we describe a case of a Korean patient with MKS.

안과질환 외래환자에 관한 임상적 분석 (A Clinical Analysis of Ophthalmologic Disease)

  • 신상호;김자혜;김민희;고우신;윤화정
    • 한방안이비인후피부과학회지
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    • 제19권3호통권31호
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    • pp.171-179
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    • 2006
  • Objective : The purpose of this study is to investigate outpatients of ophthalmologic disease who had visited to Hospital of Oriental Medicine. Method : We analyzed statistics study in 590 patients, who had visited to the Dept. of dermatology, ophthalmology & otorhinolayngology Hospital of Oriental Medicine Dongeui University from January, 1998 to July , 2006. Result : The results were as follows. 1. Distributions of sex : male 45.42%, female 54.58%. 2. The age distributions of patients showed highest in 51-60 years, followed by 41-50 years, 61-70 years in order. 3. The yearly distributions of patients showed highest in 2004, followed by 2005, 2002 in order. The seasonal distributions of patients showed highest in summer, followed by spring, winter, autumn in order. The monthly distributions of patients showed highest in August, followed by June, March in order. 4. The frequency of chief complaint showed highest in visual disorder, followed by dry eye, blepharospasm, squint in arch order. Visual disorder and dry eye were the most common ophthalmologic disease, irrespective of age. 5. The Distribution of past history showed highest in ophthalmologic disease, followed by circulatory disease, digestive disease in order. The Distribution of ophthalmologic diseases showed highest in retinal disease, followed by lens-induced ocular disease, disease of the optic nerve in order. 6. The number of times in treatment : 1-20 times(84.07%), 21-40 times(7.97%). 7. In the treatment method, a major portion of treatment methods was acupuncture & herbal medicine treatment, followed by acupuncture, consulting, herbal medicine treatment in order.

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신석회화와 소뇌 충부의 무형성을 동반한 Joubert 증후군 1례 (A Case of Joubert Syndrome Associated with Nephrocalcinosis and Agenesis of Cerebellar Vermis)

  • 김지희;신혜경;홍영숙;이주원;김순겸;유기환
    • Childhood Kidney Diseases
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    • 제6권2호
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    • pp.266-271
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    • 2002
  • Joubert 증후군은 소뇌 충부 무형성을 특징으로 하며 근 긴장 저하, 불규칙적인 호흡, 발달 지연, 안진, 망막 이형성, 낭종성 신질환, 간 섬유증, 다지증 등이 동반되는 증후군이다. 이 질환에서는 소뇌 충부의 병변과 신장의 병변이 무작위적으로 함께 나타나기도 하는데, 저자들은 소뇌 충부 무형성, 근 긴장저하, 안진, 무호흡 등이 있어 Joubert 증후군으로 진단받은 환아가 신장 수질 석회화 병변과 만성 신부전으로 진행한 1례를 경험하였기에 문헌 고찰과 함께 보고하는 바이다.

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Regulation of HIF-1α stability by lysine methylation

  • Baek, Sung Hee;Kim, Keun Il
    • BMB Reports
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    • 제49권5호
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    • pp.245-246
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    • 2016
  • The level and activity of critical regulatory proteins in cells are tightly controlled by several tiers of post-translational modifications. HIF-1α is maintained at low levels under normoxia conditions by the collaboration between PHD proteins and the VHL-containing E3 ubiquitin ligase complex. We recently identified a new physiologically relevant mechanism that regulates HIF-1α stability in the nucleus in response to cellular oxygen levels. This mechanism is based on the collaboration between the SET7/9 methyltransferase and the LSD1 demethylase. SET7/9 adds a methyl group to HIF-1α, which triggers degradation of the protein by the ubiquitin-proteasome system, whereas LSD1 removes the methyl group, leading to stabilization of HIF-1α under hypoxia conditions. In cells from knock-in mice with a mutation preventing HIF-1α methylation (Hif1αKA/KA), HIF-1α levels were increased in both normoxic and hypoxic conditions. Hif1αKA/KA knock-in mice displayed increased hematological parameters, such as red blood cell count and hemoglobin concentration. They also displayed pathological phenotypes; retinal and tumor-associated angiogenesis as well as tumor growth were increased in Hif1αKA/KA knock-in mice. Certain human cancer cells exhibit mutations that cause defects in HIF-1α methylation. In summary, this newly identified methylation-based regulation of HIF-1α stability constitutes another layer of regulation that is independent of previously identified mechanisms.

역 위상 깜박임 영역 순응에 의해 유도된 인접 영역의 3차원 운동잔여 효과 (3D motion aftereffect in a static region after adaptation to an adjacent counterphase flickering region)

  • 김정훈;남종호;정찬섭
    • 인지과학
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    • 제10권3호
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    • pp.29-37
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    • 1999
  • Murakami와 Cavanagh (1998a.b. 1999)가 보고한 무선 운동 영역 순응에 따른 정지된 인접 영역의 흔들림(jittering) 착시현상을 새로운 자극구성으로 검증하였다. 이 현상에 대한 설명으로 이 연구자들이 제안한 순응에 따른 안구운동 보상기제의 약화를 최소화하는 역 위상 깜박임(counterphase flickering)에의 순응과 코사인 패턴을 사용하였을 때에도 정지된 인접 영역에서의 착시현상이 경험되었다. 그러나, 이 자극 상황에서 관찰된 착시현상은 평면상의 흔들림이 아니라 정지된 인접 영역이 관찰자에서 멀어지는 것으로 지각되는 3차원상의 운동잔여효과(3D motion aftereffect)이었다. 본 연구에서 우리는 이 새로운 현상이 깜박임 영역의 휘도 대비감소(contrast reduction)가 정지된 인접 영역과의 지각된 깊이 차이를 유발시키고 깜박임 영역이 정지하였을 때 원래의 깊이로 복원하는 과정에서 정지된 인접 영역이 상대적으로 멀어지며 움직이는 것으로 지각되는 것에 기인했을 가능성을 조사하였다. 깊이 단서를 제거하거나, 휘도 대비감소를 최소화하는 고 공간주파수 코사인 패턴을 사용한 실험의 결과 관찰된 운동잔여효과의 소멸은 이 가능성을 강력히 지지하여 주었다.

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Detection of Ocular Toxoplasma gondii Infection in Chronic Irregular Recurrent Uveitis by PCR

  • Lee, Sang-Eun;Hong, Sung-Hee;Lee, Seong-Ho;Jeong, Young-Il;Lim, Su-Jin;Kwon, Oh-Woong;Kim, Sun-Hyun;You, Young-Sung;Cho, Shin-Hyeong;Lee, Won-Ja
    • Parasites, Hosts and Diseases
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    • 제50권3호
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    • pp.229-231
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    • 2012
  • Toxoplasma gondii is a zoonotic parasite resulting in human infections and one of the infectious pathogens leading to uveitis and retinochoroiditis. The present study was performed to assess T. gondii infection in 20 ocular patients with chronic irregular recurrent uveitis (20 aqueous humor and 20 peripheral blood samples) using PCR. All samples were analyzed by nested PCR targeting a specific B1 gene of T. gondii. The PCR-positive rate was 25% (5/20), including 5% (1) in blood samples, 25% (5) in aqueous humor samples, and 5% (1) in both sample types. A molecular screening test for T. gondii infection in ocular patients with common clinical findings of an unclear retinal margin and an inflammatory membrane over the retina, as seen by fundus examination, may be helpful for early diagnosis and treatment.

Dendropanax morbifera Extract Inhibits Intimal Hyperplasia in Balloon-Injured Rat Carotid Arteries by Modulating Phenotypic Changes in Vascular Smooth Muscle Cells

  • Lim, Leejin;Jo, Juyeong;Yoon, Sang Pil;Jang, Inyoub;Ki, Young-Jae;Choi, Dong-Hyun;Song, Heesang
    • Natural Product Sciences
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    • 제26권1호
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    • pp.71-78
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    • 2020
  • The plant Dendropanax morbifera Léveille is effective folk medicines for the treatment of several conditions, such as infectious diseases, skin diseases, and other illnesses. Although the inhibitory effects of D. morbifera on the proliferation and migration of vascular smooth muscle cells (VSMCs) have been shown in our previous study, its effects in vivo remain to be elucidated. In this study, we aimed to investigate the protective effects of the extracts from D. morbifera (EDM) on neointimal hyperplasia of rat carotid artery and explore the underlying mechanisms. We observed that the ratio of intima to media thickness (I/M) was significantly decreased in the EDM-treated groups by ~80% compared to that of the control. The expression of Ki-67 and proliferating cell nuclear antigen was decreased by ~70% in the EDM-treated groups compared to that of the control. In addition, matrix metalloproteinase (MMP)2 and MMP9 significantly reduced in the neointimal layer of the EDM-treated groups. Moreover, the decreased levels of contractile phenotypic markers of VSMCs, such as α-smooth muscle actin, myocardin, and smooth muscle-myosin heavy chain, were successfully restored by EDM treatment. Furthermore, the levels of synthetic phenotypic markers, cellular retinal binding protein 1 and connexin 43 were also restored to normal levels. These results suggest that EDM inhibits vascular neointimal hyperplasia induced by balloon injury in rats via phenotypic modulation of VSMCs. Therefore, EDM may be a potential drug candidate for the prevention of restenosis.