• 제목/요약/키워드: regeneration failure

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Are There Hopeful Therapeutic Strategies to Regenerate the Infarcted Hearts?

  • Gyu-Chul Oh;Yeon-Jik Choi;Bong-Woo Park;Kiwon Ban;Hun-Jun Park
    • Korean Circulation Journal
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    • 제53권6호
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    • pp.367-386
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    • 2023
  • Ischemic heart disease remains the primary cause of morbidity and mortality worldwide. Despite significant advancements in pharmacological and revascularization techniques in the late 20th century, heart failure prevalence after myocardial infarction has gradually increased over the last 2 decades. After ischemic injury, pathological remodeling results in cardiomyocytes (CMs) loss and fibrosis, which leads to impaired heart function. Unfortunately, there are no clinical therapies to regenerate CMs to date, and the adult heart's limited turnover rate of CMs hinders its ability to self-regenerate. In this review, we present novel therapeutic strategies to regenerate injured myocardium, including (1) reconstruction of cardiac niche microenvironment, (2) recruitment of functional CMs by promoting their proliferation or differentiation, and (3) organizing 3-dimensional tissue construct beyond the CMs. Additionally, we highlight recent mechanistic insights that govern these strategies and identify current challenges in translating these approaches to human patients.

Antiapoptotic effects of Phe140Asn, a novel human granulocyte colony-stimulating factor mutant in H9c2 rat cardiomyocytes

  • Chung, Hee Kyoung;Ko, Eun Mi;Kim, Sung Woo;Byun, Sung-June;Chung, Hak-Jae;Kwon, Moosik;Lee, Hwi-Cheul;Yang, Byoung-Chul;Han, Deug-Woo;Park, Jin-Ki;Hong, Sung-Gu;Chang, Won-Kyong;Kim, Kyung-Woon
    • BMB Reports
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    • 제45권12호
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    • pp.742-747
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    • 2012
  • Granulocyte colony-stimulating factor (G-CSF) is used for heart failure therapy and promotes myocardial regeneration by inducing mobilization of bone marrow stem cells to the injured heart after myocardial infarction; however, this treatment has one weakness in that its biological effect is transient. In our previous report, we generated 5 mutants harboring N-linked glycosylation to improve its antiapoptotic activities. Among them, one mutant (Phe140Asn) had higher cell viability than wild-type hG-CSF in rat cardiomyocytes, even after treatment with an apoptotic agent ($H_2O_2$). Cells treated with this mutant significantly upregulated the antiapoptotic proteins, and experienced reductions in caspase 3 activity and PARP cleavage. Moreover, the total number of apoptotic cells was dramatically lower in cultures treated with mutant hG-CSF. Taken together, these results suggest that the addition of an N-linked glycosylation was successful in improving the antiapoptotic activity of hG-CSF, and that this mutated product will be a feasible therapy for patients who have experienced heart failure.

전치부에서 발치와 골결손부에 따른 최적의 심미를 얻을 수 있는 수술법 (Optimized Implant treatment strategy based on a classification of extraction socket defect at anterior area)

  • 반재혁
    • 대한심미치과학회지
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    • 제25권1호
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    • pp.15-24
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    • 2016
  • 전치부에서는 비록 임플란트가 기능적으로 문제가 없다고 하더라도 심미적인 문제가 있다면 실패로 간주한다. 2003년 Kan은 임플란트의 골 레벨은 인접치아의 골 레벨에 의해 결정된다고 보고하였다. 그 후로 많은 학자들이 인접치아의 골 소실이 있는 증례에서 어떻게 심미적 결과를 얻을 수 있는지에 대하여 연구해왔다. 2012년 Takino가 지금까지 여러 저널을 정리 및 분류하여 Class 1부터 4로 발표하였다. Class 1과 2는 인접치의 골소실이 없는 경우, Class 3,4는 인접치의 골소실이 있는 경우로 나누어서 각 분류마다 최적의 심미를 얻을 수 있는 방법에 대하여 설명하였다. 인접치의 골소실이 없는 경우에는 쉽게 심미적 결과를 얻을 수 있으나 인접치까지 골소실이 있는 경우는 수술이 복잡해지고 심미적 결과를 장담하기 힘들다. 따라서 장기적인 안정적 결과를 유지하기 위해서는 인접치에 대한 골재생술이 필요하다. 하지만 그 과정이나 치료법이 너무 복잡하여 이 저널에서는 기존의 수술법을 단순화하여 쉽게 비슷한 결과를 얻을 수 방법을 보고하고자 한다.

천공형 티타늄 막의 조기 노출이 수직 골 형성에 미치는 영향 (The effect of early membrane exposure on exophytic bone formation using perforated titanium membrane)

  • 김은정;허익;권영혁;박준봉;정종혁
    • Journal of Periodontal and Implant Science
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    • 제37권2호
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    • pp.237-249
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    • 2007
  • This study was performed to evaluate the effect of membrane exposure on new bone formation when guided bone regeneration with perforated titanium membrane on atrophic alveolar ridge. The present study attempted to establish a GBR model for four adult beagle dog premolar. Intra-marrow penetration defects were created on the alveolar ridge(twelve weeks after extraction) on the mandibular premolar teeth in the beagle dogs. Space providing perforated titanium membrane with various graft material were implanted to provide for GBR. The graft material were demineralized bovine bone(DBB), Irradiated cancellous bone(ICB) and demineralized human bone powder(DFDB). The gingival flap were advanced to cover the membranes and sutured. Seven sites experienced wound failure within 2-3weeks postsurgery resulting in membrane exposure. The animals were euthanized at 4 weeks postsurgery for histologic and histometric analysis. The results of this study were as follows: 1. There was little new bone formation at 4 weeks postsurgery. irrespectively of membrane exposure. 2. There was significant relationship between membrane exposure and bone graft resorption(P<0.05), but no relation between membrane exposure and infiltrated connective tissue. 3. There was much bone graft resorption on DFDB than ICB and DBB. 4. The less exposure was on the perforated titanium membrane, the more dense infiltrated connective tissue was filled under the membrane when grafted with ICB and DBB. but there was no relationship between the rate of membrane exposure and the percentage of infiltrated connective tissue area and no relationship between the percentage of the area in the infiltrated connective tissue and in the residual bone graft. Within the above results, bone formation may be inhibited when membrane was exposed and ICB and DBB were more effective than DFDB as a bone graft material when guided bone regeneration.

디젤엔진 자동차의 EGR 및 공기 제어와 CPF 장치에 관련된 고장사례 고찰 (A Study for Failure Examples of Emission Gas Recirculation and Air Control and Catalyzed Particulate Filter System in Diesel Engine Vehicle)

  • 이일권;국창호;함성훈;이영숙;염광욱;유창배;김성모;임하영;안호철;이정호
    • 한국가스학회지
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    • 제22권2호
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    • pp.78-83
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    • 2018
  • 이 논문은 디젤엔진 자동차의 EGR 및 공기 제어와 CPF 장치에 관련된 고장사례 연구이다. 첫 번째 사례는 엔진진공펌프 손상으로 인해 엔진오일이 EGR 밸브 내부 다이어프램 손상으로 인해 오일이 흡기로 유입되어 연소실로 들어가 불완전 연소함으로써 배기할 때 매연이 발생된 것으로 확인되었다. 두 번째 사례의 원인은 공기제어 장치인 스로틀 플랩(throttle flap)을 점검하였을 때 스로틀 플랩이 고착되어 흡입공기량 부족에 의해 매연이 발생된 것을 확인하였다. 세 번째 사례는, 배기가스 온도센서의 불량으로 인해 온도를 감지하지 못해 재생기능이 되지 않아 매연이 발생된 것으로 확인되었다. 따라서, 배기가스발생으로 인한 환경오염 문제가 발생하지 않도록 최적의 상태를 유지하도록 관리하여야 한다.

Differential Expression of NCAM-180 in the Olfactory System and Retina of the Rat

  • Hyeyoung Koo
    • Animal cells and systems
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    • 제3권3호
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    • pp.259-267
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    • 1999
  • The expression of the neural cell adhesion molecule-180 (NCAM-180), which accumulates at contact sites between cells and may be responsible for the stabilization of cell contacts, was studied in the olfactory system and retina of developing and adult rats. From embryonic day 12 onwards, which was the earliest stage examined, the NCAM-180 pathway directing to the presumptive olfactory bulb was observed. In later stages, olfactory neurons and fasciculating axons in the olfactory epithelium and nerve fiber layer and glomeruli of the olfactory bulb expressed NCAM-180. From postnatal day 0, immunolabelling pattern of the olfactory epithelium and olfactory bulb were the same as that during later stages. NCAM-180 immunoreactivity was present on differentiating retinal cells and persisted on those cells throughout adulthood. However, contrary to the olfactory nerve which remained detectable in the adult, the optic nerve was only transiently expressed with NCAM-180 and was no longer detectable in the adult. The presence of NCAM-180 in olfactory tissues suggests their possible role in pathfinding, differentiation, fasciculation and synaptic plasticity. The continued presence of NCAM-180 in the olfactory system examined may underlie its continuous cell turnover and regenerative capacity. The continuous expression of NCAM-180 in ganglion cells, bipolar cells and photoreceptor cells, also suggests potential regenerating capability and some plastic functions for these cells in the adult. Since the expression of NCAM-180 by the optic nerve was restricted to the period of special histogenetic events, for example, during axonal growth and synaptogenesis, it is possible that the lack of NCAM-180 in the adult optic nerve might cause a nonpermissive environment for the regeneration and result in regenerative failure of this system.

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상악 전치부에서 단일 치아 발거 후 즉시 임플란트 식립 (Immediate implant placement in areas of aesthetic priority)

  • 이승훈;김영성;김원경;이영규
    • Journal of Periodontal and Implant Science
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    • 제37권3호
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    • pp.637-646
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    • 2007
  • Implants placed immediately after tooth extraction have been shown to be a successfully predictable treatment modality. Several clinical papers suggest that placing implants immediately after tooth extraction may provide some advantages: reduction of the number of surgical procedures or patient visits, preservation of the dimensions of alveolar ridge, and shortening of the interval between the removal of the tooth and the insertion of the implant supported restoration. In this case report, three patients received single immediate implant placements to replace a maxillary anterior tooth at the time of extraction. As the three cases were somewhat different, treatment protocols had to be modified as follows: Case 1. Immediate implant placement with healing abutment connection. Case 2. Immediate implant placement with immediate provisionalization. Case 3. Immediate implant placement with Guided Bone Regeneration(GBR). Every implant of these cases was placed in proper position buccolingually, mesiodistally and apicocoronally, The procedures following implantation such as immediate provisionalization and GBR were free of problem. Healing of each case was uneventful. In all cases, treatment outcomes were mostly satisfactory and the results maintained during follow-up periods. However, one case (Case 3) showed some papilla loss due to failure in delicate soft tissue handling during surgery. This papilla loss was compromised by prosthetic means. In conclusion, immediate implant placement in the fresh extraction socket can be a valid and successful option of treatment in aesthetic area. Moreover, this treatment protocol seems to maintain the preexisting architecture of soft and hard tissues in most cases.

Charlson comorbidity index as a predictor of periodontal disease in elderly participants

  • Lee, Jae-Hong;Choi, Jung-Kyu;Jeong, Seong-Nyum;Choi, Seong-Ho
    • Journal of Periodontal and Implant Science
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    • 제48권2호
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    • pp.92-102
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    • 2018
  • Purpose: This study investigated the validity of the Charlson comorbidity index (CCI) as a predictor of periodontal disease (PD) over a 12-year period. Methods: Nationwide representative samples of 149,785 adults aged ${\geq}60$ years with PD (International Classification of Disease, 10th revision [ICD-10], K052-K056) were derived from the National Health Insurance Service-Elderly Cohort during 2002-2013. The degree of comorbidity was measured using the CCI (grade 0-6), including 17 diseases weighted on the basis of their association with mortality, and data were analyzed using multivariate Cox proportional-hazards regression in order to investigate the associations of comorbid diseases (CDs) with PD. Results: The multivariate Cox regression analysis with adjustment for sociodemographic factors (sex, age, household income, insurance status, residence area, and health status) and CDs (acute myocardial infarction, congestive heart failure, peripheral vascular disease, cerebral vascular accident, dementia, pulmonary disease, connective tissue disorders, peptic ulcer, liver disease, diabetes, diabetes complications, paraplegia, renal disease, cancer, metastatic cancer, severe liver disease, and human immunodeficiency virus [HIV]) showed that the CCI in elderly comorbid participants was significantly and positively correlated with the presence of PD (grade 1: hazard ratio [HR], 1.11; P<0.001; grade ${\geq}2$: HR, 1.12, P<0.001). Conclusions: We demonstrated that a higher CCI was a significant predictor of greater risk for PD in the South Korean elderly population.

치은부에 발생한 거대세포육아종에 의한 골연화증 (TUMOR INDUCED OSTEOMALACIA : ASSOCIATED WITH GIANT CELL GRANULOMA ON THE GINGIVA)

  • 김여갑;류동목;이상철
    • Maxillofacial Plastic and Reconstructive Surgery
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    • 제13권2호
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    • pp.185-190
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    • 1991
  • 비내분비성 골종양이나 연조직종양에서 유래되는 구루병이나 골연화증은 매우 드문질환으로 1947 년 이래로 14 명의 환자만이 보고되고 있다. 이 질환의 본태는 아직 밝혀지지 않았으나 종양에서 생성하는 인산염뇨유발성 물질이 신세뇨관에 영향을 주고 저인산염혈증을 일으키며 골조직의 석회화에 장애를 일으키는 것으로 생각된다. 본 증례의 환자는 약 4 년 전부터 지속된 심한 전신동통과 근육위축, 현저한 신장의 감소를 주소로 내원한 41 세 남자로 상악우측 치은부의 종양에 의한 전신적 골연화증의 진단하에 종양의 외과적적출을 시행하였으며 술후 환자의 혈청과 뇨의 생화학적결과는 12 일 후에 정상으로 회복되었고 임상증상은 수술후 6 주에 회복되었으며 4 달후에 촬영한 치과 방사선상 놀랄만한 골재생과 새로 형성된 치조백선의 형성이 관찰되었다. 적출된 종물은 거대세포육아종의 조직소견을 보였으며 종물의 적출에 의하여 골연화증의 치유소견이 관찰 되었기에 종양에 의한 골연화증의 회유한 증례로 사료되어 이에 보고하는 바이다.

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치조능확장골절단술을 이용한 임프란트 식립술의 유용성 평가 (Evaluation of the Availability of Implant placement using Ridge Expansion Osteotomy (REO))

  • 김영균;윤필영;김범수
    • 대한치과의사협회지
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    • 제46권4호
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    • pp.243-247
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    • 2008
  • Purpose : Ridge expansion osteotomy (REO) has been introduced when it is necessary to expand narrow crestal ridge with simultaneous implant placement. This study has designed to evaluate the clinical availability of REO. Materials and methods : Subject were patients who had visited Seoul National University Bundang Hospital from July. 2003 to December, 2005 for implant placement using REO by one surgeon. Intraoperative and postoperative complication, failure of initial osseointegration and marginal bone resorption were estimated using electronic medical record and periapical radiography. Twenty?three patients, 8 males and 15 females, mean age 51, ranged 18 to 72, were treated for mean 26 months, ranged from 16 months to 46 months. Results : Mean diameter and length of implants placed at upper anterior, were 3.72mm and 13.32mm each other. Guided bone regeneration and ridge splitting were accompanied in this study. Five cases of cortical bone fracture, three cases of crestal bone loss more than 2mm, 2cases of gingival recession, and 2 cases of infection were noted, but there were no implants removed because of disintegration. Success rate of implant was 91.7%, even if survival rate of implant was 100%. In addition, there were no statistical significance between the success rate of REO and bone graft(p>0.05). Conclusion : Based on the results of the present study, it can be concluded that REO technique is reliable for implant placement at atrophic ridge with adequate height compared to bone graft and other osteotomies for ridge expansion, but care should be taken of esthetic problem such as gingival recession because of crestal bone resorption from trauma by osteotome.

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