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1.
Healthcare (Basel) ; 11(8)2023 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-37107922

RESUMEN

Since 2005, there have been no systematic reviews on the effects of multiple manual therapies, including muscle energy technique (MET), on the hamstrings. Therefore, this systematic review aimed to provide clinical evidence for the effectiveness of the MET on hamstring flexibility. We queried 10 electronic databases (PubMed, EMBASE, The Cochrane Library, KISS, NDSL, KMBASE, KISTI, RISS, Dbpia, and OASIS) up to the end of March 2022. This study only included randomized controlled trials (RCTs) investigating the use of MET for the hamstring. The literature was organized using Endnote. Literature screening and data extraction were conducted by two researchers independently. The methodological quality of the included RCTs was evaluated using the Cochrane risk-of-bias tool 1.0, and the meta-analysis was performed using RevMan 5.4. In total, 949 patients from 19 RCTs were selected according to the inclusion criteria. During active knee extension tests, the efficacy between MET and other manipulations did not significantly differ. For sit and reach tests, MET groups had higher flexibility compared to stretching (MD = 1.69, 95% CI: 0.66 to 2.73, p = 0.001) and no treatment (MD = 2.02, 95% CI: 0.70 to 3.33, p = 0.003) groups. No significant differences were observed in the occurrence of adverse reactions. Overall, we found that MET is more efficacious for improving hamstring flexibility compared to stretching and having no treatment during sit and reach tests because it combines isometric contraction with stretching. Owing to clinical heterogeneity, uncertain risk of bias, and the small number of included studies, further high-quality studies should assess the effectiveness of MET.

2.
Medicine (Baltimore) ; 101(45): e31311, 2022 Nov 11.
Artículo en Inglés | MEDLINE | ID: mdl-36397335

RESUMEN

Kyung-ok-ko (KOK), a traditional medicinal formula in East Asia, has been recently studied across various fields. However, comprehensive reviews of clinical applications of KOK targeting clinical and experimental studies are lacking. Therefore, the application of KOK is being limited to the range of tonic medicines. To overcome this limitation, we aim to investigate the effectiveness, mechanism, and safety of KOK to obtain evidence regarding its effects in clinical applications. We searched for clinical and experimental articles in 11 databases (PubMed, Cochrane Library, Excerpta Medica dataBASE, China National Knowledge Infrastructure, Google Scholar, Research Information Sharing Service, Oriental Medicine Advanced Searching Integrated System, Koreanstudies Information Service System, Korean Medical Database, DBpia, and ScienceON). We selected 54 studies based on the inclusion criteria. Three clinical studies used KOK for a consumptive disease and health promotion. Fifty-one experimental studies reported the antioxidant activity, neuroprotective activity, anticancer effect, anti-inflammatory activity, immunological activity, growth promotion, impacts on cardiovascular system diseases, gastrointestinal system diseases, respiratory system diseases, and metabolic bone disease, hepatoprotective function, and antifatigue function of KOK, which were considered effective and safe in consumptive, chronic, metabolic, inflammatory, and immune diseases. We identified the effectiveness of KOK in the treatment of a wide range of diseases. However, further clinical studies are warranted in the future.


Asunto(s)
Medicamentos Herbarios Chinos , Medicina Tradicional de Asia Oriental , Humanos , Medicamentos Herbarios Chinos/uso terapéutico , China , Asia Oriental
3.
Nat Commun ; 13(1): 6431, 2022 10 28.
Artículo en Inglés | MEDLINE | ID: mdl-36307483

RESUMEN

Neuromorphic computing, an alternative for von Neumann architecture, requires synapse devices where the data can be stored and computed in the same place. The three-terminal synapse device is attractive for neuromorphic computing due to its high stability and controllability. However, high nonlinearity on weight update, low dynamic range, and incompatibility with conventional CMOS systems have been reported as obstacles for large-scale crossbar arrays. Here, we propose the CMOS compatible gate injection-based field-effect transistor employing thermionic emission to enhance the linear conductance update. The dependence of the linearity on the conduction mechanism is examined by inserting an interfacial layer in the gate stack. To demonstrate the conduction mechanism, the gate current measurement is conducted under varying temperatures. The device based on thermionic emission achieves superior synaptic characteristics, leading to high performance on the artificial neural network simulation as 93.17% on the MNIST dataset.


Asunto(s)
Redes Neurales de la Computación , Sinapsis
4.
Integr Med Res ; 9(3): 100492, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32802745

RESUMEN

BACKGROUND: Since January 2020, novel coronavirus (SARS-Cov-2) - infected pneumonia (COVID-19) rapidly spread in Korea. This study aimed to introduce the Korean Medicine (KM) telemedicine center for treatment of COVID patients in Korea. METHODS: This work was a retrospective review of medical records on patients who received at least one telemedicine session from March 9, 2020 to April 12, 2020 provided by the COVID-19 telemedicine center of Korean Medicine. Data on demographic characteristics, treatment frequency, number of consultation were collected. A descriptive statistical analysis was conducted to report characteristics of patients. RESULTS: A total of 1742 patients underwent consultation through KM telemedicine centers. Despite the rapid increase in the number of patients, the telemedicine center provided treatments to an average of 192 patients per day by about an average of 15 doctors. Furthermore, 4552 herbal medicines were prescribed through telemedicine center, among which 1366 cases (30%) being Qing-Fei-Pai-Du-tang. Telemedicine care also has shown that even with patient's residence transition, medical care can be continued without pause. CONCLUSION: These results show some advantages of the telemedicine center's implementation in terms of the effective use of medical resources and continuous treatment for patients.

5.
Arch Plast Surg ; 47(3): 235-241, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32453932

RESUMEN

BACKGROUND: This is the first clinical study conducted among Asian women using breast implants manufactured by an Asian company. Four-year data regarding the safety and efficacy of BellaGel breast implants have already been published, and we now report 6-year data. METHODS: This study was designed to take place over 10 years. It included 103 patients who underwent breast reconstruction or augmentation using BellaGel breast implants. The rates of implant rupture and capsular contracture were measured and analyzed to evaluate the effectiveness of the breast implant. RESULTS: At patients' 6-year postoperative visits, the implant rupture and capsular contracture rates were 1.15% and 2.30%, respectively. The implant rupture rate was 3.77% among reconstruction cases and 0% among augmentation cases. The capsular contracture rate was 5.66% among reconstruction cases and 0.83% among augmentation cases. CONCLUSIONS: The 6-year data from this planned 10-year study suggest that the BellaGel cohesive silicone gel-filled breast implant is an effective and safe medical device that can be used in breast reconstruction and augmentation.

6.
Biomater Sci ; 8(10): 2825-2839, 2020 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-32343757

RESUMEN

Adenosine and its receptors have emerged as alternative targets to control cellular functions for bone healing. However, the soluble delivery of adenosine has not proven effective because of its fast degradation in vivo. We therefore designed a stable coating of adenosine for biomaterial surfaces through polydopamine chemistry to control osteogenesis and osteoclastogenesis via A2bR signaling. First, we prepared electrospun poly (ι-lactic acid) (PLLA) nanofiber sheets, which were modified through a one-step adenosine polydopamine coating process. Scanning electron microscopy (SEM) revealed deposition of particles on the adenosine polydopamine-coated PLLA (AP-PL) sheets compared to the polydopamine-only sheets. Moreover, X-ray photoelectron spectroscopy analysis confirmed an increase in nitrogen signals due to adenosine. Furthermore, adenosine loading efficiency and retention were significantly enhanced in AP-PL sheets compared to polydopamine-only sheets. Human adipose-derived stem cells (hADSCs) cultured on AP-PL expressed A2bR (1.30 ± 0.19 fold) at significantly higher levels than those cultured on polydopamine-only sheets. This in turn significantly elevated the expression of Runx2 (16.94 ± 1.68 and 51.69 ± 0.07 fold), OPN (1.63 ± 0.16 and 30.56 ± 0.25 fold), OCN (1.16 ± 0.13 and 5.23 ± 0.16 fold), and OSX (10.01 ± 0.81 and 62.48 ± 0.25 fold) in cells grown in growth media on days 14 and 21, respectively. Similarly, mineral deposition was enhanced to a greater extent in the AP-PL group than the polydopamine group, while blocking of A2bR significantly downregulated osteogenesis. Finally, osteoclast differentiation of RAW 264.7 cells was significantly inhibited by growth on AP-PL sheets. However, osteoclast differentiation was significantly stimulated after A2bR was blocked. Taken together, we propose that polydopamine-assisted one-step coating of adenosine is a viable method for surface modification of biomaterials to control osteogenic differentiation of stem cells and bone healing.


Asunto(s)
Adenosina/química , Diferenciación Celular , Indoles/química , Células Madre Mesenquimatosas/citología , Nanofibras/química , Osteoclastos/citología , Polímeros/química , Animales , Células Cultivadas , Humanos , Ácido Láctico/química , Ratones , Estructura Molecular , Osteogénesis , Tamaño de la Partícula , Células RAW 264.7 , Propiedades de Superficie
7.
In Vivo ; 34(2): 815-824, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32111789

RESUMEN

BACKGROUND/AIM: Bone tissue engineering is an emerging field of regenerative medicine that holds promise for the restoration of bones affected by trauma, neoplastic diseases, and congenital deformity. During the past decade, bone tissue engineering has evolved from the use of biomaterials that can only replace small areas of damaged bone, to the use of scaffolds in which grafts can be seeded before implantation. This case report proposes an alternative option for a veterinary patient suffering from ectrodactyly, which is one of several congenital deformities in dogs. A 2-month-old male toy poodle dog with ectrodactyly was treated using several stages of surgery involving pancarpal arthrodesis, limb lengthening, and bone tissue engineering techniques. RESULTS AND CONCLUSION: Over a period of 2 years, the operated limb gained almost the same function as the contralateral limb. Bone tissue engineering techniques can be used for the treatment of congenital deformities in dogs.


Asunto(s)
Huesos/cirugía , Extremidades/cirugía , Deformidades Congénitas de las Extremidades/cirugía , Procedimientos Ortopédicos , Ingeniería de Tejidos , Animales , Artrodesis , Perros , Extremidades/diagnóstico por imagen , Deformidades Congénitas de las Extremidades/diagnóstico por imagen , Masculino , Procedimientos Ortopédicos/métodos , Radiografía , Medicina Regenerativa , Ingeniería de Tejidos/métodos , Resultado del Tratamiento
8.
Artículo en 0 | WPRIM (Pacífico Occidental) | ID: wpr-830743

RESUMEN

Background@#This is the first clinical study conducted among Asian women using breast implants manufactured by an Asian company. Four-year data regarding the safety and efficacy of BellaGel breast implants have already been published, and we now report 6-year data. @*Methods@#This study was designed to take place over 10 years. It included 103 patients who underwent breast reconstruction or augmentation using BellaGel breast implants. The rates of implant rupture and capsular contracture were measured and analyzed to evaluate the effectiveness of the breast implant. @*Results@#At patients’ 6-year postoperative visits, the implant rupture and capsular contracture rates were 1.15% and 2.30%, respectively. The implant rupture rate was 3.77% among reconstruction cases and 0% among augmentation cases. The capsular contracture rate was 5.66% among reconstruction cases and 0.83% among augmentation cases. @*Conclusions@#The 6-year data from this planned 10-year study suggest that the BellaGel cohesive silicone gel-filled breast implant is an effective and safe medical device that can be used in breast reconstruction and augmentation.

9.
Acta Biomater ; 74: 464-477, 2018 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-29803004

RESUMEN

Development of a bone-like 3D microenvironment with stem cells has always been intriguing in bone tissue engineering. In this study, we fabricated composite spheroids by combining functionalized fibers and human adipose-derived stem cells (hADSCs), which were fused to form a 3D mineralized tissue construct. We prepared fragmented poly (ι-lactic acid) (PLLA) fibers approximately 100 µm long by partial aminolysis of electrospun fibrous mesh. PLLA fibers were then biomineralized with various concentrations of NaHCO3 (0.005, 0.01, and 0.04 M) to form mineralized fragmented fibers (mFF1, mFF2, and mFF3, respectively). SEM analysis showed that the minerals in mFF2 and mFF3 completely covered the fiber surface, and surface chemistry analysis confirmed the presence of hydroxyapatite peaks. Additionally, mFFs formed composite spheroids with hADSCs, demonstrating that the cells were strongly attached to mFFs and homogeneously distributed throughout the spheroid. In vitro culture of spheroids in the media without osteogenic supplements showed significantly enhanced expression of osteogenic genes including Runx2 (20.83 ±â€¯2.83 and 22.36 ±â€¯2.18 fold increase), OPN (14.24 ±â€¯1.71 and 15.076 ±â€¯1.38 fold increase), and OCN (4.36 ±â€¯0.41 and 5.63 ±â€¯0.51 fold increase) in mFF2 and mFF3, respectively, compared to the no mineral fiber group. In addition, mineral contents were significantly increased at day 7. Blocking the biomineral-mediated signaling by PSB 603 significantly down regulated the expression of these genes in mFF3 at day 7. Finally, we fused composite spheroids to form a mineralized 3D tissue construct, which maintained the viability of cells and showed pervasively distributed minerals within the structure. Our composite spheroids could be used as an alternative platform for the development of in vitro bone models, in vivo cell carriers, and as building blocks for bioprinting 3D bone tissue. STATEMENT OF SIGNIFICANCE: This manuscript described our recent work for the preparation of biomimeral-coated fibers that can be assembled with mesenchymal stem cells and provide bone-like environment for directed control over osteogenic differentiation. Biomineral coating onto synthetic, biodegradable single fibers was successfully carried out using multiple steps, combination of template protein coating inspired from mussel adhesion and charge-charge interactions between template proteins and mineral ions. The biomineral-coated single micro-scale fibers (1-2.5 µm in diameter) were then assembled with human adipose tissue derived stem cells (hADSCs). The assembled structure exhibited spheroidal architecture with few hundred micrometers. hADSCs within the spheroids were differentiated into osteogenic lineage in vitro and mineralized in the growth media. These spheroids were fused to form in vitro 3D mineralized tissue with larger size.


Asunto(s)
Tejido Adiposo/metabolismo , Bioimpresión , Calcificación Fisiológica , Diferenciación Celular , Materiales Biocompatibles Revestidos/química , Nanofibras/química , Esferoides Celulares/metabolismo , Tejido Adiposo/citología , Antígenos de Diferenciación/biosíntesis , Humanos , Esferoides Celulares/citología , Ingeniería de Tejidos
10.
J Biomed Mater Res A ; 106(6): 1732-1742, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29468791

RESUMEN

Biological responses on biomaterials occur either on their surface or at the interface. Therefore, surface characterization is an essential step in the fabrication of ideal biomaterials for achieving effective control of the interaction between the material surface and the biological environment. Herein, we applied femtosecond laser ablation on electrospun fibrous scaffolds to fabricate various hierarchical patterns with a focus on the alignment of cells. We investigated the simultaneously stimulated response of cardiomyoblasts based on multiple topographical cues, including scales, oriented directions, and spatial arrangements, in the fibrous scaffolds. Our results demonstrated a synergistic effect on cell behaviors of one or more structural arrangements in a homogeneous orientation, whereas antagonistic effects were observed for cells arranged on a surface with heterogeneous directions. Taken together, these results indicate that our hierarchically patterned fibrous scaffolds may be useful tools for understanding the cellular behavior on fibrous scaffolds used to mimic an extracellular matrix-like environment. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 106A: 1732-1742, 2018.


Asunto(s)
Materiales Biocompatibles/química , Mioblastos Cardíacos/citología , Andamios del Tejido/química , Animales , Diferenciación Celular , Línea Celular , Movimiento Celular , Proliferación Celular , Supervivencia Celular , Técnicas Electroquímicas , Rayos Láser , Ratas , Propiedades de Superficie , Ingeniería de Tejidos/métodos
11.
Acta Biomater ; 64: 161-175, 2017 12.
Artículo en Inglés | MEDLINE | ID: mdl-29037892

RESUMEN

Extracellular matrix (ECM) microenvironment is critical for the viability, stemness, and differentiation of stem cells. In this study, we developed hybrid-spheroids of human turbinate mesenchymal stem cells (hTMSCs) by using extracellular matrix (ECM) mimicking fragmented fibers (FFs) for improvement of the viability and functions of hTMSCs. We prepared FFs with average size of 68.26 µm by partial aminolysis of poly L-lactide (PLLA) fibrous sheet (FS), which was coated with polydopamine for improved cell adhesion. The proliferation of hTMSCs within the hybrid-spheroids mixed with fragmented fibers was significantly increased as compared to that from the cell-only group. Cells and fragmented fibers were homogenously distributed with the presence of pore like empty spaces in the structure. LOX-1 staining revealed that the hybrid-spheroids improved the cell viability, which was potentially due to enhanced transport of oxygen through void space generated by engineered ECM. Transmission electron microscopy (TEM) analysis confirmed that cells within the hybrid-spheroid formed strong cell junctions and contacts with fragmented fibers. The expression of cell junction proteins including connexin 43 and E-cadherin was significantly upregulated in hybrid-spheroids by 16.53 ±â€¯0.04 and 28.26 ±â€¯0.11-fold greater than that from cell-only group. Similarly, expression of integrin α2, α5, and ß1 was significantly enhanced at the same group by 25.72 ±â€¯0.13, 27.48 ±â€¯0.49, and 592.78 ±â€¯0.06-fold, respectively. In addition, stemness markers including Oct-4, Nanog, and Sox2 were significantly upregulated in hybrid-spheroids by 96.56 ±â€¯0.06, 158.95 ±â€¯0.06, and 115.46 ±â€¯0.47-fold, respectively, relative to the cell-only group. Additionally, hTMSCs within the hybrid-spheroids showed significantly greater osteogenic differentiation under osteogenic media conditions. Taken together, our hybrid-spheroids can be an ideal approach for stem cell expansion and serve as a potential carrier for bone regeneration. STATEMENT OF SIGNIFICANCE: Cells are spatially arranged within extracellular matrix (ECM) and cell/ECM interactions are crucial for cellular functions. Here, we developed a hybrid-spheroid system incorporating engineered ECM prepared from fragmented electrospun fibers to tune stem cell functions. Conventionally prepared cell spheroids with large diameters (>200 µm) is often prone to hypoxia. In contrast, the hybrid-spheroids significantly enhanced viability and proliferation of human turbinate mesenchymal stem cells (hTMSCs) as compared to spheroid prepared from cell only. Under these conditions, the presence of fragmented fibers also improved maintenance of stemness of hTMSCs for longer time cultured in growth media and demonstrated significantly greater osteogenic differentiation under osteogenic media conditions. Thus, the hybrid-spheroids can be used as a delivery carrier for stem cell based therapy or a 3D culture model for in vitro assay.


Asunto(s)
Comunicación Celular , Matriz Extracelular/química , Células Madre Mesenquimatosas/metabolismo , Nanofibras/química , Esferoides Celulares/metabolismo , Nicho de Células Madre , Andamios del Tejido/química , Matriz Extracelular/ultraestructura , Humanos , Células Madre Mesenquimatosas/ultraestructura , Nanofibras/ultraestructura , Esferoides Celulares/ultraestructura
12.
BMC Vet Res ; 13(1): 198, 2017 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-28651609

RESUMEN

BACKGROUND: Platelet-rich plasma (PRP) has been expected for regenerative medicine because of its growth factors. However, there is considerable variability in the recovery and yield of platelets and the concentration of growth factors in PRP preparations. The aim of this study was to identify optimal relative centrifugal force and spin time for the preparation of PRP from canine blood using a double-centrifugation tube method. METHODS: Whole blood samples were collected in citrate blood collection tubes from 12 healthy beagles. For the first centrifugation step, 10 different run conditions were compared to determine which condition produced optimal recovery of platelets. Once the optimal condition was identified, platelet-containing plasma prepared using that condition was subjected to a second centrifugation to pellet platelets. For the second centrifugation, 12 different run conditions were compared to identify the centrifugal force and spin time to produce maximal pellet recovery and concentration increase. Growth factor levels were estimated by using ELISA to measure platelet-derived growth factor-BB (PDGF-BB) concentrations in optimised CaCl2-activated platelet fractions. RESULTS: The highest platelet recovery rate and yield were obtained by first centrifuging whole blood at 1000 g for 5 min and then centrifuging the recovered platelet-enriched plasma at 1500 g for 15 min. This protocol recovered 80% of platelets from whole blood and increased platelet concentration six-fold and produced the highest concentration of PDGF-BB in activated fractions. CONCLUSIONS: We have described an optimised double-centrifugation tube method for the preparation of PRP from canine blood. This optimised method does not require particularly expensive equipment or high technical ability and can readily be carried out in a veterinary clinical setting.


Asunto(s)
Centrifugación/veterinaria , Perros , Plasma Rico en Plaquetas , Animales , Becaplermina , Separación Celular/métodos , Separación Celular/veterinaria , Centrifugación/métodos , Masculino , Proteínas Proto-Oncogénicas c-sis/análisis
13.
J Mater Chem B ; 5(2): 318-328, 2017 Jan 14.
Artículo en Inglés | MEDLINE | ID: mdl-32263550

RESUMEN

A monolayer of endothelial cells (ECs) aligned along the direction of blood flow plays crucial roles in the regulation of anti-thrombogenic and pro-inflammatory reactions in the blood vessel wall. Thus, many researchers have attempted to mimic the aligned structure of ECs in vascular grafts or tissue-engineered blood vessels. In the present study, we fabricated micro-groove patterned nanofibers using a femtosecond laser ablation technique to recapitulate the densely organized anisotropic architecture of the endothelial layer. Femtosecond laser ablation enabled us to generate high-resolution groove patterns (10 µm width) with 20 or 80 µm gaps on randomly oriented electrospun nanofibers. The patterned nanofibers exhibited anisotropic (transverse: 101.1 ± 4.0° and longitudinal: 123.5 ± 9.4°) water contact angles; however, the mechanical properties were consistent in both directions. The micropatterned nanofibers modulated the aligned structure or aspect ratio (20 µm: 0.23 ± 0.11 and 80 µm: 0.42 ± 0.18) of ECs along the pattern direction. In particular, the engineered aligned endothelial layer was effective in eliciting an anti-inflammatory response (approximately 50% greater than that of random or aligned nanofibers), thereby effectively preventing monocyte adhesion following activation by TNF-α treatment. Therefore, micropatterning by laser ablation can be utilized to generate high-resolution microgrooves on various substrates, thereby providing fundamental platforms for vascular tissue engineering.

14.
J Mater Chem B ; 5(44): 8725-8737, 2017 Nov 28.
Artículo en Inglés | MEDLINE | ID: mdl-32264266

RESUMEN

In a large tissue defect, faster migration of adjacent tissue toward the defect shortens the tissue regeneration time. Little has been explored on guiding of directional migration from all fronts of the defect boundary towards the center in tissue engineering. This paper demonstrates the effect of radially aligned fibrous scaffolds (RAFSs) coated with polydopamine in order to guide directional migration of human mesenchymal stem cells (hMSCs). RAFSs were electrospun using a collector with a set of electrodes, each constructed with a metallic ring and a point. The polydopamine was then coated by dipping the scaffolds in a dopamine solution (PD-RAFS). The RAFSs exhibited radial distribution of the fibers from the peripheral region toward the center, and polydopamine was uniformly coated over the entire surface by presenting characteristics of the aromatic ring from dopamine. When hMSCs were seeded on the scaffolds, cells grew in an elongated form toward the center along the fiber direction. In particular, the polydopamine coating improved adhesion and spreading of hMSCs on the scaffolds while preserving initial cell orientation. The hMSCs migrated toward the center of the scaffolds at the border of the seeded area; it was enhanced in the order of PD-RAFS > RAFS > random fibrous scaffolds. Therefore, PD-RAFSs can be utilized as an alternate scaffold that can lead to fast and directional migration of cells for finally facilitating tissue regeneration.

15.
J Cell Biol ; 162(2): 293-303, 2003 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-12860966

RESUMEN

Homers are scaffolding proteins that bind G protein-coupled receptors (GPCRs), inositol 1,4,5-triphosphate (IP3) receptors (IP3Rs), ryanodine receptors, and TRP channels. However, their role in Ca2+ signaling in vivo is not known. Characterization of Ca2+ signaling in pancreatic acinar cells from Homer2-/- and Homer3-/- mice showed that Homer 3 has no discernible role in Ca2+ signaling in these cells. In contrast, we found that Homer 2 tunes intensity of Ca2+ signaling by GPCRs to regulate the frequency of [Ca2+]i oscillations. Thus, deletion of Homer 2 increased stimulus intensity by increasing the potency for agonists acting on various GPCRs to activate PLCbeta and evoke Ca2+ release and oscillations. This was not due to aberrant localization of IP3Rs in cellular microdomains or IP3R channel activity. Rather, deletion of Homer 2 reduced the effectiveness of exogenous regulators of G proteins signaling proteins (RGS) to inhibit Ca2+ signaling in vivo. Moreover, Homer 2 preferentially bound to PLCbeta in pancreatic acini and brain extracts and stimulated GAP activity of RGS4 and of PLCbeta in an in vitro reconstitution system, with minimal effect on PLCbeta-mediated PIP2 hydrolysis. These findings describe a novel, unexpected function of Homer proteins, demonstrate that RGS proteins and PLCbeta GAP activities are regulated functions, and provide a molecular mechanism for tuning signal intensity generated by GPCRs and, thus, the characteristics of [Ca2+]i oscillations.


Asunto(s)
Proteínas Portadoras/metabolismo , Proteínas de Unión al GTP/metabolismo , Proteínas Activadoras de GTPasa/metabolismo , Isoenzimas/metabolismo , Neuropéptidos/metabolismo , Proteínas RGS/metabolismo , Fosfolipasas de Tipo C/metabolismo , Animales , Bombesina/farmacología , Calcio/metabolismo , Calcio/farmacocinética , Señalización del Calcio , ATPasas Transportadoras de Calcio/antagonistas & inhibidores , ATPasas Transportadoras de Calcio/metabolismo , Carbacol/farmacología , Proteínas Portadoras/química , Proteínas Portadoras/genética , Colecistoquinina/farmacología , Agonistas Colinérgicos/farmacología , Inhibidores Enzimáticos/farmacología , Proteínas de Unión al GTP/agonistas , Eliminación de Gen , Proteínas de Andamiaje Homer , Indoles/farmacología , Ratones , Ratones Noqueados , Neuropéptidos/química , Neuropéptidos/genética , Páncreas/citología , Páncreas/efectos de los fármacos , Páncreas/metabolismo , Fosfatidilinositol 4,5-Difosfato/metabolismo , Fosfolipasa C beta , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , ATPasas Transportadoras de Calcio del Retículo Sarcoplásmico
16.
Artículo en Inglés | WPRIM (Pacífico Occidental) | ID: wpr-7332

RESUMEN

Li-Fraumeni syndrome(LFS) is an autosomal dominant disorder that predisposes individuals to multiple forms of cancer including breast cancer, soft tissue sarcoma, brain tumor, osteosarcoma, leukemia, and adrenocortical carcinoma. Recently, germ-line mutation of the p53 tumor suppressor gene has been implicated in this familial disorder. We report a case of a 25-year old woman who presented with bilateral breast cancer and uterine leiomyoma. Her mother had died of early-onset bilateral breast cancer. And her younger sister had breast carcinoma as well, which was identified at the age of 22, indicating her strong familial history. To test for the presence of the p53 germ-line mutation, we analyzed the genomic DNA from the peripheral blood of the proband and her sister by PCR-SSCP analysis of exon 5 through exon 8 of the p53 gene. As a result, a p53 mutation in exon 7 was detected in an allele, and it was shared with her sister as the same pattern. Sequencing analysis determined the altered nucleotide at codon 248(CGG < TGG) which is one of the most frequent mutation sites related to LFS. Therefore, this patient has the most consistent characteristic features of LFS phenotype and it is believed that this case is the first report of a family with Li-Fraumeni syndrome carrying the p53 germ-line mutation in Korea.


Asunto(s)
Adulto , Femenino , Humanos , Secuencia de Bases , Neoplasias de la Mama/diagnóstico , Genes p53 , Mutación de Línea Germinal , Corea (Geográfico) , Síndrome de Li-Fraumeni/diagnóstico , Datos de Secuencia Molecular , Linaje , Reacción en Cadena de la Polimerasa , Polimorfismo Conformacional Retorcido-Simple , Análisis de Secuencia de ADN
17.
Artículo en Coreano | WPRIM (Pacífico Occidental) | ID: wpr-767982

RESUMEN

Eleventh heel pad reconstruction with neurovascularized dorsalis pedis free flap or rotation flap have performed during recent three years in department of Orthopedic Surgery, Kyung Hee University Hospital. Neurovascularized dorsalis pedis free flaps were seven and neurovascularized dorsalis pedis rotation flaps were four. All patients had complained of painful limping and ulceration in grafted heel. In 5 months to 34 months follow up study, the following results were obtained. The success rate of dorsalis pedis flap was 100% except one partial peripheral necrosis. The weight bearing function and tactile protective sensation on reconstructed heel pads were excellent. Neurovascularized dorsalis pedis free flap or rotation flap is recommended to satisfactory methods in heel pad reconstruction. Neurovascularized dorsalis pedis rotation flap easier and safer technique than neurovascularized dorsalis free flap.


Asunto(s)
Humanos , Estudios de Seguimiento , Colgajos Tisulares Libres , Talón , Necrosis , Ortopedia , Sensación , Trasplantes , Úlcera , Soporte de Peso
18.
Artículo en Coreano | WPRIM (Pacífico Occidental) | ID: wpr-768002

RESUMEN

Two patients with flexor paralysis of the elbow due to brachial plexus injury and three patients with flexor paralysis of the wrist and fingers due to Volkmann's contracture were treated by transplantation of the gracilis muscle which was detached at both ends and transferred to replace the biceps and long finger flexors, preserving its long and lax neurovascular pedicle. At eleven to fifteen months after operation, the strength and flexion of the elbow were satisfactory and the additional cosmetic effect was obtained. This method should be performed only after a complete study of the patient's general functional needs and the condition of the affected arm, forearm and hand.


Asunto(s)
Humanos , Brazo , Plexo Braquial , Contractura , Codo , Dedos , Antebrazo , Mano , Métodos , Parálisis , Muñeca
19.
Artículo en Coreano | WPRIM (Pacífico Occidental) | ID: wpr-767834

RESUMEN

Several attempts have been made to assess the relative importance of the vasa nervorum and the intrinsic longitudinal vascular plexuses of nerve in maintaining the blood supply of a segment of nerve trunk, but the effect of mobilization on the ability of an injuried or repaired nerve to regenerate and regain function has been less certain and is the subject of these investigations. Thirty-two Korean rabbits of both sexes were used for these studies and we concluded that it is increased fibrosis with adhesion to surrounded tissues, loss of glistening and milk-like discoloration of never grossly, and increased degeneration and milk-like discoloration of nerve grossly, and increased degeneration of axons and demyelization progressively and early proliferated Schwann cells with increasing length of neurolysis. And there was no recovery of damage in nerve tissue induced by above 7 cm of neurolysis. (1:35)


Asunto(s)
Conejos , Axones , Fibrosis , Tejido Nervioso , Células de Schwann , Nervio Ciático , Vasa Nervorum
20.
Artículo en Coreano | WPRIM (Pacífico Occidental) | ID: wpr-767864

RESUMEN

An arteriovenous fistula may be defined as a vascular abnormality in which there are one or more direct or indirect communication between an artery and a vein without any intervening capillary bed. Largely, such fistulas are divided into two groups-acquired (traumatic) or congenital in origin. There is a general agreement that congenital A-V fistula results from a failure in differentiation of the common embryonic anlage into true artery and vein. The authors have experienced a case of congenital A-V fistula formed in the 4th finger of the left hand. Such fistula is very difficult to excise completely with the conventional method. But we have obtained the excellent result by utilizing advanced meticulous microsurgical technique in excision.


Asunto(s)
Arterias , Fístula Arteriovenosa , Capilares , Dedos , Fístula , Mano , Métodos , Microcirugia , Venas
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