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1.
Sci Adv ; 7(47): eabj6895, 2021 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-34788088

RESUMO

Epithelial barriers that prevent dehydration and pathogen invasion are established by tight junctions (TJs), and their disruption leads to various inflammatory diseases and tissue destruction. However, a therapeutic strategy to overcome TJ disruption in diseases has not been established because of the lack of clinically applicable TJ-inducing molecules. Here, we found TJ-inducing peptides (JIPs) in mice and humans that corresponded to 35 to 42 residue peptides of the C terminus of alpha 1-antitrypsin (A1AT), an acute-phase anti-inflammatory protein. JIPs were inserted into the plasma membrane of epithelial cells, which promoted TJ formation by directly activating the heterotrimeric G protein G13. In a mouse intestinal epithelial injury model established by dextran sodium sulfate, mouse or human JIP administration restored TJ integrity and strongly prevented colitis. Our study has revealed TJ-inducing anti-inflammatory physiological peptides that play a critical role in tissue repair and proposes a previously unidentified therapeutic strategy for TJ-disrupted diseases.

2.
J Clin Orthop Trauma ; 22: 101589, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34540585

RESUMO

Tibial condylar valgus osteotomy (TCVO) is an intra-articular proximal tibial osteotomy developed in 1989 and has since been used for the treatment of knee osteoarthritis (OA) associated with genu varum. This article describes the surgical technique and clinical results of TCVO. TCVO can be used for all grades of varus knee OA in patients of any age. he preoperative range of movement should be at least 90°. Preoperative screening showed varus-valgus instability due to an intra-articular deformity of the proximal tibia. Using intraoperative image intensification, a sagittally oriented "L"-shaped osteotomy is made from the medial to the tibial tuberosity to the center of the tibial plateau between the medial and lateral tibial spines. The separation of the osteotomy using the lamina spreader is gradually increased using an image intensifier guidance until the articular surface of the lateral tibial plateau comes in contact with the articular surface of the lateral femoral condyle. Adequate correction is indicated by parallelism of the lateral tibial plateau and a line tangential to the distal convexity of the lateral femoral condyle on an anteroposterior (AP) image and the elimination of the valgus instability with the knee in extended position. A "T"-plate (locking or non-locking plate or circular external fixator) is used to fix the osteotomy in the corrected position. Synthetic or autologous bone grafts can be used. We used the Japanese Orthopaedic Association score to evaluate the patient's function and also measured the %MAD, medial plateau opening angle, medial plateau angle, and lateral plateau opening angle on an AP view of the long length roentgenogram of the lower limb (standing position). The JOA score, radiologically measured values, and instability of the knee joint remarkably improved.

3.
J Clin Orthop Trauma ; 22: 101588, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34527512

RESUMO

Teramoto distal tibial oblique osteotomy (DTOO) is a joint-preserving surgery for ankle osteoarthritis (AOA). However, there are few articles on the radiological assessment of DTOO. The purpose of this study was to report the clinical outcomes and radiological evaluations of weight-bearing radiographs before and after DTOO. We retrospectively reviewed 52 patients who underwent DTOO between 2007 and 2018. We recorded the Tanaka-Takakura classification, fixation methods, Japanese Society for Surgery of the Foot Ankle/Hindfoot Scale (JSSF scale), and complications. The tibial articular surface angle (TAS), medial malleolar angle (MMA), tibial lateral surface angle (TLS), talar tilt angle (TTA), and tibiotalar surface angle (TTS) were evaluated using weight-bearing ankle radiographs. The median patient age was 66 years, and the mean follow-up duration was 46 ± 23 months. Two stage 2, 9 stage 3a, 30 stage 3b, and 11 stage 4 according to the Tanaka-Takakura classification were performed using DTOO. The JSSF scale improved significantly from 39.9 ± 13.8 before surgery to 87.2 ± 7.5 after surgery. Seven cases were fixed using a locking plate, and 45 cases were fixed using a circular external fixator. The TAS, MMA, TLS, TTA, and TTS significantly changed before and after DTOO. Radiological evaluation indicated that DTOO influences talar behavior during weight-bearing, and improves the clinical outcomes of AOA.

4.
Injury ; 52(11): 3516-3527, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34462118

RESUMO

INTRODUCTION: Traumatic osteoarthritis of the ankle joint caused after malleolar fractures of the ankle and tibial plafond fractures are frequently observed in comparatively young and highly active patients. Since the ankle movement in these patients is in general, comparatively favorable, orthopedists may sometimes have difficulty in deciding on a treatment policy. In our department, when treating traumatic osteoarthritis patients having a movable range within their ankle joints, we proactively applied distal tibial oblique osteotomy (DTOO) developed by Dr. Teramoto in 1994 or intra-articular osteotomy developed based on DTOO concepts such as distal tibial intra-articular osteotomy (DTIO) and distal fibular oblique osteotomy (DFOO).The objectives of the current study are to radiologically assess the ankle joint after intra-articular osteotomy for traumatic ankle osteoarthritis and evaluate the change in configuration of the ankle joint. This study summarizes the clinical results of intra-articular osteotomy obtained through the above-mentioned study. PATIENTS AND METHODS: The subjects of this study were 20 patients diagnosed with traumatic osteoarthritis who were surgically treated for a total of 20 ankles. All patients underwent treatment with intra-articular osteotomy and were evaluated retrospectively for the following parameters: surgical procedure, fixation devices, clinical results based on the Japanese Society for Surgery of the Foot ankle/hindfoot scale (hereafter, JSSF scale) and post-operative adverse events. They were also assessed radiologically with pre- and post-operative anterior-posterior (AP) and lateral weight-bearing ankle radiographs. RESULTS: The 20 patients consisted of 12 males and 8 females. The median age at surgery was 49 years old (range 14 - 87 years old) and the average follow-up period was 42 months (range 19 to 121 months). DTOO was applied to 10 cases, DFOO to 2 cases, DTOO and DFOO to 2 cases, medial-distal tibial intra-articular osteotomy (M-DTIO) and DFOO to 1 case, lateral-distal tibial intra-articular osteotomy (L-DTIO) and DFOO to 3 cases, M-DTIO followed by DTOO and DFOO to 1 case, and DTOO followed by low tibial osteotomy (LTO) to 1 case. Fixation devices utilized included circular external fixator for 15 cases, locking compression plate (LCP) to 3 cases, LCP and Kirschner-wire (K-wire) to 1 case, and screw and K-wire to 1 case. Radiological assessment revealed significant changes in the following parameters after surgery: tibial ankle surface angle (TAS, P= 0.0203), tibiotalar surface angle (TTS, P= 0.0021), medial malleolar angle (MMA, P= 0.0217), empirical axis (EA, P= 0.0019), fibular angle (FA, P= 0.0002), talar tilt angle (TTA, P= 0.0374), and tibial lateral surface angle (TLS, P= 0.0279). The JSSF scale also improved significantly after surgery (pre-operative JSSF scale: 51.1±11.0, post-operative JSSF scale: 89.2±8.2), p=0.0001. CONCLUSION: Intra-articular osteotomy may change the radiological configuration of the ankle in a weight-bearing state. The present study showed very good short-term clinical results. Intra-articular osteotomy can prove a viable surgical option applicable for treatment of patients with traumatic ankle osteoarthritis having a reasonable range of motion within their ankle joints.


Assuntos
Articulação do Tornozelo , Osteoartrite , Tornozelo , Articulação do Tornozelo/diagnóstico por imagem , Articulação do Tornozelo/cirurgia , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Osteoartrite/diagnóstico por imagem , Osteoartrite/cirurgia , Osteotomia , Estudos Retrospectivos
5.
Med Image Anal ; 72: 102097, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34107343

RESUMO

When using deep neural networks in medical image classification tasks, it is mandatory to prepare a large-scale labeled image set, and this often requires significant effort by medical experts. One strategy to reduce the labeling cost is group-based labeling, where image samples are clustered and then a label is attached to each cluster. The efficiency of this strategy depends on the purity of the clusters. Constrained clustering is an effective way to improve the purity of the clusters if we can give appropriate must-links and cannot-links as constraints. However, for medical image clustering, the conventional constrained clustering methods encounter two issues. The first issue is that constraints are not always appropriate due to the gap between semantic and visual similarities. The second issue is that attaching constraints requires extra effort from medical experts. To deal with the first issue, we propose a novel soft-constrained clustering method, which has the ability to ignore inappropriate constraints. To deal with the second issue, we propose a self-constrained clustering method that utilizes prior knowledge about the target images to set the constraints automatically. Experiments with the endoscopic image datasets demonstrated that the proposed methods give clustering results with higher purity.


Assuntos
Endoscopia , Redes Neurais de Computação , Análise por Conglomerados , Humanos , Semântica
6.
Nat Commun ; 12(1): 480, 2021 01 20.
Artigo em Inglês | MEDLINE | ID: mdl-33473127

RESUMO

The cytoplasm in mammalian cells is considered homogeneous. In this study, we report that the cytoplasmic fluidity is regulated in the blebbing cells; the cytoplasm of rapidly expanding membrane blebs is more disordered than the cytoplasm of retracting blebs. The increase of cytoplasmic fluidity in the expanding bleb is caused by a sharp rise in the calcium concentration. The STIM-Orai1 pathway regulates this rapid and restricted increase of calcium in the expanding blebs. Conversely, activated ERM protein binds to Orai1 to inhibit the store-operated calcium entry in retracting blebs, which results in decreased in cytoplasmic calcium, rapid reassembly of the actin cortex.


Assuntos
Cálcio/metabolismo , Membrana Celular/metabolismo , Citoplasma/metabolismo , Proteína ORAI1/metabolismo , Molécula 1 de Interação Estromal/metabolismo , Citoesqueleto de Actina , Actinas/metabolismo , Animais , Sinalização do Cálcio/fisiologia , Linhagem Celular , Linhagem Celular Tumoral , Proteínas do Citoesqueleto/antagonistas & inibidores , Células HEK293 , Humanos , Proteínas de Membrana/fisiologia
7.
Injury ; 51(4): 871-877, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32143858

RESUMO

OBJECTIVE: There are currently no robust methods for accurately localizing the infection focus of osteomyelitis. Accumulation of fluorodeoxyglucose (FDG) is nonspecific, and it is well-known that it can indicate inflammatory cells and sites of inflammation, and its effectiveness in detecting osteomyelitis has been reported recently. However, the optimal cut-off value for the Standardized Uptake Value (SUV) in detecting the focus of osteomyelitis through 18F-FDG-PET/CT is not known. We investigated the optimal SUV cut-off values using 18F-FDG positron emission tomography (PET)computed tomography (CT) to visualize the infection focus of osteomyelitis accurately. PATIENTS AND METHODS: Initially, we investigated a case where osteomyelitis was bacteriologically detected after orthopedic surgery on lower limb. Based on the surgical pathology, we explored the optimal SUV cut-off value of the 18F-FDG PET/CT image taken before surgery. The SUV cut-off value was varied, using the GE Rainbow Color Scale on a dedicated workstation. We searched for the most accurate visualization of the extent of the infectious lesion. Subsequently, using the SUV cut-off value decided on the basis of the first case studied, we investigated the accuracy for diagnosing osteomyelitis. A total of sixteen patients underwent 18F-FDG PET/CT for suspected osteomyelitis (one case involved the upper extremity and 15 cases the lower one). All patients underwent surgery. The final diagnosis was made by means of bacteriologic culture of surgical specimens and histopathologic analysis. We compared surgical pathology and preoperative 18F-FDG PET/CT. RESULTS: In the first case studied, the infection was most accurately localized with a SUV with a lower level of 2.00 and an upper of 8.00. Upon comparing the pathological findings and the 18F-FDG PET/CT, we set a SUV with a lower level of 2.00 and an upper level of 8.00. In thirteen cases, infection was detected with positive pathological findings. Preoperative 18F-FDG PET/CT showed high accumulation in these cases. In the remaining three cases, no infection was detected on either pathological findings nor 18F-FDG PET/CT findings. CONCLUSIONS: The infection focus of osteomyelitis was accurately visualized by setting the SUV cut-off lower level to 2.00 and upper level to 8.00. We believe that this 18F-FDG PET/CT technique is helpful for image guided surgery of osteomyelitis.


Assuntos
Fluordesoxiglucose F18 , Osteomielite/diagnóstico , Osteomielite/patologia , Tomografia por Emissão de Pósitrons/métodos , Tomografia Computadorizada por Raios X/métodos , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Osteomielite/cirurgia , Cirurgia Assistida por Computador , Adulto Jovem
8.
Mol Biol Cell ; 31(8): 833-844, 2020 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-32049595

RESUMO

Apoptotic cells form membrane blebs, but little is known about how the formation and dynamics of membrane blebs are regulated. The size of blebs gradually increases during the progression of apoptosis, eventually forming large extracellular vesicles called apoptotic bodies that have immune-modulating activities. In this study, we investigated the molecular mechanism involved in the differentiation of blebs into apoptotic blebs by comparing the dynamics of the bleb formed during cell migration and the bleb formed during apoptosis. We revealed that the enhanced activity of ROCK1 is required for the formation of small blebs in the early phase of apoptosis, which leads to the physical disruption of nuclear membrane and the degradation of Lamin A. In the late phase of apoptosis, the loss of asymmetry in phospholipids distribution caused the enlargement of blebs, which enabled translocation of damage-associated molecular patterns to the bleb cytoplasm and maturation of functional apoptotic blebs. Thus, changes in cell membrane dynamics are closely linked to cytoplasmic changes during apoptotic bleb formation.


Assuntos
Apoptose/fisiologia , Extensões da Superfície Celular/metabolismo , Citoplasma/metabolismo , Adenocarcinoma/patologia , Amidas/farmacologia , Caspase 3/metabolismo , Linhagem Celular Tumoral , Movimento Celular , Extensões da Superfície Celular/ultraestrutura , Neoplasias do Colo/patologia , Cicloeximida/farmacologia , Ativação Enzimática , Genes Reporter , Humanos , Lamina Tipo A/metabolismo , Lipídeos de Membrana/metabolismo , Proteínas de Neoplasias/metabolismo , Fosfolipídeos/metabolismo , Proteólise , Piridinas/farmacologia , Proteínas Recombinantes de Fusão/metabolismo , Proteínas rho de Ligação ao GTP/metabolismo , Quinases Associadas a rho/antagonistas & inibidores , Quinases Associadas a rho/metabolismo , Proteína rhoA de Ligação ao GTP/metabolismo
9.
Trauma Case Rep ; 23: 100234, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31388542

RESUMO

A severely comminuted and contaminated open tibial pilon fracture is one of the most challenging fractures we face. Although nowadays conducting multiple operations over various stages is a common treatment option taking into account the possibility of soft tissue damage, a gold standard protocol for severe pilon fractures has not yet been established. This case concerns a 56-year-old gentleman who suffered a severely comminuted and contaminated Gustilo 3b open tibial pilon fracture (AO 43C3.3) that was successfully treated using a circular frame external fixator without flap. Two years six months after the injury, there were no indications of any skin conditions at the site of the open wound, the range of ankle motion had been maintained and independent walking was possible. The score under the JSSF (Japanese Society of Surgery of the foot) ankle/hind foot scale was 81. This indicates that use of a circular frame external fixator is a useful treatment method in the event of a severe open pilon fracture where there is a large osteochondral bone defect.

10.
Annu Int Conf IEEE Eng Med Biol Soc ; 2019: 3681-3684, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31946675

RESUMO

In this paper, we propose a clustering method with temporal ordering information for endoscopic image sequences. It is difficult to collect a sufficient amount of endoscopic image datasets to train machine learning techniques by manual labeling. The clustering of endoscopic images leads to group-based labeling, which is useful for reducing the cost of dataset construction. Therefore, in this paper, we propose a clustering method where the property of endoscopic image sequences is fully utilized. For the proposed method, a deep neural network was used to extract features from endoscopic images, and clustering with temporal ordering information was solved by dynamic programming. In the experiments, we clustered the esophagogastroduodenoscopy images. From the results, we confirmed that the performance was improved by using the sequential property.


Assuntos
Análise por Conglomerados , Endoscopia , Processamento de Imagem Assistida por Computador , Aprendizado de Máquina , Redes Neurais de Computação , Endoscopia do Sistema Digestório , Humanos
11.
Strategies Trauma Limb Reconstr ; 13(1): 43-49, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29380255

RESUMO

We have devised a medial peri-articular osteotomy, the distal tibial oblique osteotomy (DTOO), and have used this technique since 1994 for ankle osteoarthritis of advanced and late stages associated with varus inclination. This report describes the surgical technique and its applicability. DTOO can be used for cases of varus ankle osteoarthritis with a range of the ankle joint movement of at least 10° or more. The osteotomy is obliquely directed cut across the distal tibia from proximal-medial to distal lateral and is of an opening-wedge type with the centre of rotation coincident with the centre of the tibiofibular joint. A laminar spreader instrument is inserted in the osteotomy to open the wedge until the lateral surface of the talar body is seen on X-ray to be in contact and congruent with medial articular surface of the lateral malleolus. Common obstacles which may prevent this contact and congruency are bony spurs present on the anterior side of fibula or on the lateral side of the tibia; these require removal. The opening-wedge osteotomy is held in position by an Ilizarov external fixator or internally fixed with a plate. Bone graft is taken from the iliac crest and inserted into the open wedge. If, after completion of the osteotomy, the dorsiflexion angle of the ankle joint does not exceed 0°, a Z-lengthening is performed of the Achilles tendon. In the DTOO for ankle osteoarthritis, the contact area of the ankle joint increases and decreases the load pressure per unit area. Furthermore, as the width of the ankle mortice is restored through the realignment of the body of the talus, instability at the ankle joint decreases. There is additional improvement with restoration of the inclination of the distal tibial articular surface as this directs the hindfoot valgus and corrects the alignment of the foot, with consequent improvement of ankle pain.

12.
Genes Genet Syst ; 92(2): 59-71, 2017 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-28344191

RESUMO

We developed an insertion sequence transposition detection system called the "jumping cat assay" and applied it to the Bacillus subtilis chromosome using IS256Bsu1 derived from B. subtilis natto. The high frequency of transposition enabled us to explore host factors; combining the assay and genetic analyses revealed that recA is essential for the transposition of IS256Bsu1. Detailed analyses using various domain mutants of recA demonstrated that this essentiality is not related to the function of recA in homologous recombination. Instead, the ATP binding and hydrolysis function seemed to be crucial for IS transposition. To elucidate the role of recA, we focused on the muB gene of the enterobacteriophage Mu. Based on information from the NCBI Conserved Domain Database, both MuB and RecA belong to the P-loop dNTPase superfamily. Further experiments revealed that muB complements the transposition-defective phenotype of a recA deletant, although it could not rescue UV sensitivity. These results suggest that recA shares a common function with muB that helps the transposition of IS256Bsu1 in B. subtilis.


Assuntos
Bacillus subtilis/genética , Proteínas de Bactérias/metabolismo , Elementos de DNA Transponíveis , Recombinases Rec A/metabolismo , Trifosfato de Adenosina/metabolismo , Proteínas de Bactérias/genética , Proteínas de Ligação a DNA/genética , Recombinação Homóloga , Mutação , Ligação Proteica , Recombinases Rec A/genética , Proteínas Virais/genética
13.
PLoS One ; 7(10): e48512, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23144766

RESUMO

Peptide immunotherapy using T-cell epitopes is expected to be an effective treatment for allergic diseases such as Japanese cedar (Cryptomeria japonica; Cj) pollinosis. To develop a treatment for pollen allergy by inducing oral tolerance, we generated genetically manipulated (GM) chickens by retroviral gene transduction, to produce a fusion protein of chicken egg white lysozyme and a peptide derived from seven dominant human T-cell epitopes of Japanese cedar pollen allergens (cLys-7crp). The transgene sequence was detected in all chickens transduced with the retroviral vector. Transduction efficiency in blood cells correlated to transgene expression. Western blot analysis revealed that cLys-7crp was expressed in the egg white of GM hens. Mice induced to develop allergic rhinitis by Cj pollinosis were fed with cLys-7crp-containing egg white produced by GM chickens. Total and Cj allergen (Cry j 1)-specific IgE levels were significantly decreased in allergic mice fed with cLys-7crp-containing egg white compared with allergic mice fed with normal egg white. These results suggest that oral administration of T-cell epitope-containing egg white derived from GM chickens is effective for the induction of immune tolerance as an allergy therapy.


Assuntos
Alérgenos/imunologia , Clara de Ovo , Epitopos de Linfócito T/imunologia , Imunoterapia/métodos , Proteínas Recombinantes de Fusão/imunologia , Rinite Alérgica Sazonal/imunologia , Administração Oral , Alérgenos/genética , Alérgenos/metabolismo , Animais , Animais Geneticamente Modificados , Sequência de Bases , Western Blotting , Embrião de Galinha , Galinhas , Cryptomeria/imunologia , Ensaio de Imunoadsorção Enzimática , Epitopos de Linfócito T/genética , Epitopos de Linfócito T/metabolismo , Humanos , Imunoglobulina E/sangue , Imunoglobulina E/imunologia , Camundongos , Dados de Sequência Molecular , Muramidase/genética , Muramidase/imunologia , Muramidase/metabolismo , Células NIH 3T3 , Pólen/imunologia , Proteínas Recombinantes de Fusão/administração & dosagem , Proteínas Recombinantes de Fusão/metabolismo , Rinite Alérgica Sazonal/terapia , Resultado do Tratamento
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