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1.
Cancer Immunol Res ; 11(6): 847-862, 2023 06 02.
Artículo en Inglés | MEDLINE | ID: mdl-36988477

RESUMEN

The repertoire of tumor-infiltrating T cells is an emerging method for characterizing effective antitumor T-cell responses. Oligoclonal expansion of the tumor T-cell repertoire has been evaluated; however, their association with antitumor effects is unclear. We demonstrate here that the polyclonal fraction of the tumor-reactive T-cell repertoire, consisting of relatively minor clones, increased in tumor-bearing mice treated with monoclonal anti-programmed death-ligand 1 (PD-L1) or anti-CD4, which correlated with antitumor effects. Meanwhile, the size of the oligoclonal fraction consisting of major clones remained unchanged. Moreover, the polyclonal fraction was enriched in progenitor exhausted T cells, which are essential for a durable antitumor response, and was more dependent on CCR7+ migratory dendritic cells, which are responsible for priming tumor-reactive T cells in the tumor-draining lymph nodes. These results suggest that the expansion of diverse tumor-reactive clones ("clonal spreading") represents characteristics of antitumor T-cell responses induced by anti-CD4 and anti-PD-L1 treatment.


Asunto(s)
Neoplasias , Linfocitos T , Ratones , Animales , Linfocitos Infiltrantes de Tumor , Células Clonales , Inmunidad , Linfocitos T CD8-positivos , Línea Celular Tumoral
2.
Microsurgery ; 43(4): 357-364, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36647842

RESUMEN

BACKGROUND: The vertical profunda artery perforator (v-PAP) flap is limited in terms of the tissue volume that can be harvested but is a suitable graft for Japanese patients with relatively small breast sizes. The objectives of this study were to identify the parameter most closely correlated with v-PAP flap weight on computed tomography angiography (CTA) images and to create an easy-to-use v-PAP flap weight estimation formula by linear regression analysis using the identified parameter. PATIENTS AND METHODS: Thirty v-PAP flaps in 25 patients who underwent breast reconstruction were retrospectively analyzed. Mean age was 46.1 (range: 32-73) years, and mean BMI was 20.0 (range: 15.3-23.6) kg/m2 . On a CT horizontal section of the thigh taken at level of the center of the long axis of the flap, the following parameters were measured from the anterior margin of the gracilis muscle to the posterior margin of the semimembranosus muscle using image processing software: fat area, fat thickness, thigh circumference, and skin paddle area. Linear regression analysis was then performed with the weight of the harvested v-PAP flap as the objective variable and the above parameters as explanatory variables to predict skin flap weight. RESULTS: Correlations with v-PAP flap weight of each parameter were as follows: r = 0.66 (p < .0001) for fat thickness, r = 0.32 (p = .081) for total thigh area, r = 0.36 (p = .054) for thigh circumference, r = 0.27 (p = .153) for skin paddle area, and r = 0.84 (p < .0001) for fat area. Thus, the fat area had the strongest correlation with v-PAP flap weight. The v-PAP flap weight estimation formula obtained by linear regression analysis including fat area was as follows: 7.3 × fat area + 114 (coefficient of determination: R2  = 0.70, p < .0001, RMSE = 24). The engraftment rate of the 30 v-PAP flaps was 100%. One patient developed postoperative venous thrombosis at the vascular anastomosis site, but underwent successful microsurgical revision, leading to flap salvage. During the >6-month follow-up period, there were no notable complications in the reconstructed breasts and donor sites. CONCLUSIONS: The v-PAP flap weight estimation formula we developed in this study showed a high correlation with measured values, allowing for easy estimation using only a single CTA horizontal section of the thigh.


Asunto(s)
Mamoplastia , Colgajo Perforante , Humanos , Persona de Mediana Edad , Colgajo Perforante/irrigación sanguínea , Angiografía por Tomografía Computarizada , Estudios Retrospectivos , Mamoplastia/métodos , Arterias/cirugía , Muslo/cirugía , Muslo/irrigación sanguínea , Tomografía Computarizada por Rayos X
3.
Materials (Basel) ; 15(3)2022 Jan 27.
Artículo en Inglés | MEDLINE | ID: mdl-35160952

RESUMEN

The influence of the nanocrystalline structure produced by severe plastic deformation (SPD) on the corrosion behavior of CoCrFeMnNi alloys with Cr contents ranging from 0 to 20 at.% was investigated in aqueous 0.5 M H2SO4 and 3.5% NaCl solutions. The resistance to general corrosion and pitting became higher in both the solutions, with higher passivation capability observed with increasing Cr content, and it is believed that the high corrosion resistance of CoCrFeMnNi alloys can be attributed to the incorporation of the Cr element. However, the impact of the nanocrystalline structure produced by SPD on the corrosion behavior was negligibly small. This is inconsistent with reports on nanocrystalline binary Fe-Cr alloys and stainless steels processed by SPD, where grain refinement by SPD results in higher corrosion resistance. The small change in the corrosion behavior with respect to grain refinement is discussed, based on the passivation process of Fe-Cr alloys and on the influence of the core effects of HEAs on the passivation process.

4.
Front Immunol ; 12: 744381, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34759926

RESUMEN

Temporal analysis of the T cell receptor (TCR) repertoire has been used to monitor treatment-induced changes in antigen-specific T cells in patients with cancer. However, the lack of experimental models that allow a temporal analysis of the TCR repertoire in the same individual in a homogeneous population limits the understanding of the causal relationship between changes in TCR repertoire and antitumor responses. A bilateral tumor model, where tumor cells were inoculated bilaterally into the backs of mice, could be used for temporal analysis of the TCR repertoire. This study examined the prerequisite for this strategy: the TCR repertoire is conserved between bilateral tumors that grow symmetrically. Bilateral tumors and draining lymph nodes (dLNs) were collected 13 days after tumor inoculation to analyze the TCR repertoire of CD4+ and CD8+ T cells. The tumor-infiltrating T-cell clones were highly similar between the bilateral tumors and expanded to a similar extent. In addition, the differences of TCR repertoire between the bilateral tumors were equivalent to Intra-tumoral heterogeneity on one side. On the other hand, the similarity of the TCR repertoire in the bilateral dLNs was markedly lower than that in the tumor, suggesting that tumor-reactive T cell clones induced independently in each dLN are mixed during recirculation and then proportionally infiltrated the bilateral tumors. These findings provide the basis for future analysis of temporal and treatment-induced changes in tumor-reactive T cell clones using this bilateral tumor model.


Asunto(s)
Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD8-positivos/inmunología , Linfocitos Infiltrantes de Tumor/inmunología , Neoplasias Experimentales/inmunología , Receptores de Antígenos de Linfocitos T/inmunología , Animales , Modelos Animales de Enfermedad , Ratones
5.
Biochem Biophys Res Commun ; 577: 32-37, 2021 11 05.
Artículo en Inglés | MEDLINE | ID: mdl-34500233

RESUMEN

4,8-Sphingadienines (SD), metabolites of glucosylceramides (GlcCer), are sometimes determined as key mediators of the biological activity of dietary GlcCer, and cis/trans geometries of 4,8-SD have been reported to affect its activity. Since regulating excessive activation of mast cells seems an important way to ameliorate allergic diseases, this study was focused on cis/trans stereoisomeric-dependent inhibitory effects of 4,8-SD on mast cell activation. Degranulation of RBL-2H3 was inhibited by treatment of 4-cis-8-trans- and 4-cis-8-cis-SD, and their intradermal administrations ameliorated ear edema in passive cutaneous anaphylaxis reaction, but 4-trans-8-trans- and 4-trans-8-cis-SD did not. Although the activation of mast cells depends on the bound IgE contents, those stereoisomers did not affect IgE contents on RBL-2H3 cells after the sensitization of anti-TNP IgE. These results indicated that 4-cis-8-trans- and 4-cis-8-cis-SD directly inhibit the activation of mast cells. In conclusion, it was assumed that 4,8-SD stereoisomers with cis double bond at C4-position shows anti-allergic activity by inhibiting downstream pathway after activation by the binding of IgE to mast cells.


Asunto(s)
Antialérgicos/farmacología , Degranulación de la Célula/efectos de los fármacos , Etanolaminas/farmacología , Mastocitos/efectos de los fármacos , Anafilaxis Cutánea Pasiva/efectos de los fármacos , Animales , Antialérgicos/química , Células CACO-2 , Línea Celular Tumoral , Oído/patología , Edema/prevención & control , Etanolaminas/química , Etanolaminas/metabolismo , Femenino , Glucosilceramidas/química , Glucosilceramidas/metabolismo , Glucosilceramidas/farmacología , Humanos , Mastocitos/fisiología , Ratones Endogámicos BALB C , Estructura Molecular , Extractos Vegetales/química , Extractos Vegetales/farmacología , Ratas , Estereoisomerismo
6.
Neural Netw ; 139: 179-198, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33740581

RESUMEN

Optimal feedback control is an established framework that is used to characterize human movement. However, it is not fully understood how the brain computes optimal gains through interactions with the environment. In the past study, we proposed a model of motor learning that identifies a set of feedback and feedforward controllers and a state predictor of the arm musculoskeletal system to control free reaching movements. In this study, we applied the model to force field adaptation tasks where normal reaching movements are disturbed by an external force imposed on the hand. Without a priori knowledge about the arm and environment, the model was able to adapt to the force field by generating counteracting forces to overcome it in a manner similar to what is reported in the behavioral literature. The kinematics of the movements generated by our model share characteristic features of human movements observed before and after force field adaptation. In addition, we demonstrate that the structure and learning algorithm introduced in our model induced a shift in the end-point's equilibrium position and a static force modulation, accompanied by a fast and a slow learning process. Importantly, our model does not require desired trajectories, yields movements without specifying movement duration, and predicts force generation patterns by exploring the environment. Our model demonstrates a possible mechanism through which the central nervous system may control and adapt a point-to-point reaching movement without specifying a desired trajectory by continuously updating the body's musculoskeletal model.


Asunto(s)
Adaptación Fisiológica , Modelos Neurológicos , Movimiento , Redes Neurales de la Computación , Brazo/fisiología , Fenómenos Biomecánicos , Retroalimentación , Humanos
7.
Anaerobe ; 51: 124-130, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29753109

RESUMEN

During research to identify fibronectin (Fn)-binding proteins (Fbps) on the surface of Clostridium perfringens cells, we identified glyceraldehyde-3-phosphate dehydrogenase (GAPDH) as a candidate Fbp. GAPDH is a glycolytic enzyme found in a wide range of prokaryotes and eukaryotes. The Fn-binding activity of recombinant C. perfringens GAPDH (rGAPDH) was investigated using both ligand blotting analysis and enzyme-linked immunosorbent assay (ELISA). rGAPDH strongly bound plasminogen but not laminin or gelatin. Although GAPDH has no signal sequence, it is expressed on the cell surface of many microorganisms. The presence of GAPDH on the surface of C. perfringens cells was analyzed using ELISA and flow cytometry analyses; purified rGAPDH bound to the surface of C. perfringens cells. As autolysin is reportedly involved in the binding of GAPDH to the cell surface, we evaluated the interaction between rGAPDH and the C. perfringens autolysin Acp by both ELISA and ligand blotting assay. These assays revealed that rGAPDH binds to the catalytic domain of Acp but not the cell wall binding domains. These results suggest that autolysin mediates expression of GAPDH on the surface of C. perfringens cells and indicate a possible moonlighting function for GAPDH in binding both Fn and plasminogen.


Asunto(s)
Clostridium perfringens/enzimología , Gliceraldehído-3-Fosfato Deshidrogenasas/metabolismo , Proteínas de la Membrana/metabolismo , Proteínas Bacterianas/metabolismo , Far-Western Blotting , Proteínas Portadoras/metabolismo , Ensayo de Inmunoadsorción Enzimática , Citometría de Flujo , Humanos , Péptidos y Proteínas de Señalización Intracelular , N-Acetil Muramoil-L-Alanina Amidasa/metabolismo , Plasminógeno/metabolismo , Unión Proteica , Mapeo de Interacción de Proteínas , Proteínas Recombinantes/metabolismo
8.
Org Lett ; 20(6): 1589-1592, 2018 03 16.
Artículo en Inglés | MEDLINE | ID: mdl-29488386

RESUMEN

A novel cascade reaction of indole-2,3-epoxide equivalents with γ-carbolines by utilizing a double "open and shut" transformation to access multiheterocyclic compounds containing both isotryptamines and pyrimido[1,6- a]indoles has been developed. This strategy utilizes the in situ formation of a bulky quaternary ammonium salt via ammonium exchange, which undergoes Hofmann elimination/vinylogous Mannich/retro-Mannich/cyclization cascade sequences.

9.
Chem Asian J ; 1(1-2): 121-4, 2006 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-17441046

RESUMEN

A highly enantioselective Michael reaction of beta-ketoesters with alpha,beta-unsaturated ketones promoted by a chiral scandium catalyst has been developed. In the presence of Sc(OTf)3 and (S,S)-6,6'-bis(1-hydroxy-2,2'-dimethylpropyl)-2,2'-bipyridine, the desired Michael reactions proceeded smoothly in dichloroethane at 40 degrees C to afford the corresponding adducts in good to high yields with excellent enantioselectivities in most cases. It was found in this reaction that a lower concentration of the reaction mixture was key to attaining high enantioselectivities.


Asunto(s)
Ésteres/química , Escandio/química , Catálisis , Estereoisomerismo
10.
Org Lett ; 7(21): 4729-31, 2005 Oct 13.
Artículo en Inglés | MEDLINE | ID: mdl-16209521

RESUMEN

[reaction: see text] Catalytic asymmetric hydroxymethylation of silicon enolates with an aqueous formaldehyde solution has been developed using a chiral bismuth complex. This is the first example of highly enantioselective reactions using a chiral bismuth catalyst in aqueous media. In this paper, we have added Bi(OTf)(3)-1 complex as a "water-compatible Lewis acid". Bi(OTf)3 is unstable in the presence of water but is stabilized by the basic ligand.


Asunto(s)
2,2'-Dipiridil/química , Mesilatos/química , Agua/química , Catálisis , Cristalografía por Rayos X , Modelos Moleculares , Estructura Molecular , Compuestos de Silicona/química , Estereoisomerismo
12.
J Am Chem Soc ; 124(46): 13678-9, 2002 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-12431089

RESUMEN

Catalytic asymmetric intramolecular [3 + 2] cycloaddition of hydrazone/olefins has been attained. In the presence of a chiral zirconium catalyst prepared from zirconium alkoxide and a BINOL derivative, the desired pyrazolidine derivatives were obtained in high yields with high selectivities. The products were easily converted to 1,3-diamine or beta-aminonitrile derivatives by N-N bond cleavage.

13.
J Am Chem Soc ; 124(13): 3292-302, 2002 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-11916413

RESUMEN

Catalytic asymmetric aldol reactions of silyl enol ethers with aldehydes (Mukaiyama aldol reactions) have been performed using novel chiral zirconium catalysts. The reactions proceeded in high yields under mild conditions, and anti-adducts were obtained in high diastereo- and enantioselectivities. The catalysts were first prepared from zirconium(IV) tert-butoxide (Zr(O(t)Bu)(4)), (R)-3,3'-diiodo-1,1'-binaphthalene-2,2'-diol ((R)-3,3'-I(2)BINOL), a primary alcohol, and a small amount of water. It was revealed that the primary alcohol played an important role in completing the catalytic cycle and that a small amount of water was essential for obtaining high selectivities. Moreover, activities of the chiral zirconium catalysts were enhanced by using new ligands, (R)-3,3'-I(2)-6,6'-X(2)BINOL (X = Br, I, C(2)F(5)), and it has been shown that even aldol reactions of less reactive substrates proceeded smoothly using the novel zirconium catalysts. Finally, NMR studies of these catalysts were performed, which suggested that the catalyst would form a dimeric structure and that the water affected the catalyst formation.


Asunto(s)
Alcoholes/química , Aldehídos/química , Compuestos Organometálicos/química , Agua/química , Circonio/química , Catálisis , Espectroscopía de Resonancia Magnética , Naftoles/química , Estereoisomerismo
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