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2.
BMC Gastroenterol ; 22(1): 310, 2022 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-35751039

RESUMEN

INTRODUCTION: Patients with ulcerative colitis (UC) are known to have a significantly poor quality of life due to bowel frequency (night) and urgent defecation. Budesonide foam is a topical medication that was approved in Japan in 2017 for the treatment of UC. However, its efficacy in the treatment of bowel frequency (night) or urgent defecation is unknown. This study aimed to explore the efficacy of budesonide foam for the alleviation of these symptoms. METHODS: UC patients who received budesonide foam between December 2017 and January 2020 at the Jikei University School of Medicine in Tokyo were enrolled. The simple clinical colitis activity index (SCCAI) was evaluated at the start of budesonide foam treatment and 2 and 6 weeks later in patients who initially scored ≥ 1 for bowel frequency (night) and urgent defecation, respectively. We also studied the effect of budesonide foam on remaining symptoms in patients who had used 5-aminosalicylic acid (5-ASA) topical treatment, those with SCCAI ≥ 3, and those in remission with residual symptoms (SCCAI 1 or 2). RESULTS: Of the 233 enrolled patients, 102 were eligible for the study. In 36 patients with bowel frequency (night) treated with budesonide foam were significantly effective, score in SCCAI decreased from 1.17 ± 0.45 at baseline to 0.53 ± 0.61 at week 2 (p < 0.0001) and 0.17 ± 0.38 at week 6 (p < 0.0001). In 45 patients with urgent defecation score in SCCAI decreased significantly from 1.33 ± 0.52 at baseline to 0.44 ± 0.59 at week 2 (p < 0.0001) and 0.22 ± 0.40 at week 6 (p < 0.0001). Of 22 patients who switched from topical 5-ASA administration to budesonide foam, nine at week 2 (41%) and 11 (50%) at week 6 were improved with no symptoms, and there were no cases of worsened symptoms. No severe side effects associated with budesonide foam were observed. CONCLUSION: Budesonide foam administration significantly improves both bowel frequency (night) and urgent defecation-related UC activity and is also effective for the patients who were refractory to topical 5-ASA administration.


Asunto(s)
Budesonida , Colitis Ulcerosa , Budesonida/efectos adversos , Budesonida/uso terapéutico , Colitis Ulcerosa/inducido químicamente , Colitis Ulcerosa/tratamiento farmacológico , Defecación , Humanos , Mesalamina/uso terapéutico , Calidad de Vida , Resultado del Tratamiento
3.
J Gastroenterol Hepatol ; 37(5): 847-854, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35064604

RESUMEN

BACKGROUND AND AIM: Ulcerative colitis (UC) is usually detected by clinical symptoms, such as bleeding and diarrhea; however, it is rather difficult to assess during asymptomatic clinical remission (CR). Hence, there is a need for a biomarker that can reliably detect UC during remission. We previously reported on the utility of the prostaglandin E-major urinary metabolite (PGE-MUM) as a biomarker reflecting UC activity. In this study, we evaluated the effectiveness of the PGE-MUM in the diagnosis of endoscopic, histological, and histo-endoscopic mucosal remission of UC, comparing with fecal tests. METHODS: This prospective study was conducted at the Jikei University Hospital between August 2017 and January 2021. Patients with UC in CR scheduled to undergo colonoscopy were included. The association between the PGE-MUM with endoscopic remission (ER), histological remission (HR), and complete mucosal healing (CMH, defined as histo-endoscopic remission) was analyzed. We also compared the area under the curve (AUC) for the receiver operating characteristic curves between PGE-MUM, fecal calprotectin (FC), and fecal immunochemical test (FIT). RESULTS: In total, 128 patients were analyzed. PGE-MUM differed significantly in ER versus non-ER (14.5 vs 16.7, P = 0.028), HR versus non-HR (14.2 vs 17.4, P = 0.004), and CMH versus non-CMH (14.3 vs 16.7, P = 0.021). There were no significant differences between the AUCs for PGE-MUM, FC, and FIT for ER, HR, or CMH. CONCLUSIONS: The PGE-MUM can determine CMH in UC even during CR, regardless of the disease phenotype, indicating its clinical benefit for non-invasive monitoring.


Asunto(s)
Colitis Ulcerosa , Biomarcadores/análisis , Colitis Ulcerosa/patología , Colonoscopía , Heces/química , Humanos , Mucosa Intestinal/patología , Complejo de Antígeno L1 de Leucocito , Estudios Prospectivos , Prostaglandinas , Índice de Severidad de la Enfermedad
4.
Dig Dis ; 40(2): 239-245, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-34000716

RESUMEN

OBJECTIVES: The aim of this study was to propose an endoscopic classification system for ulcerative lesions on the ileocecal valve and investigate its relevance to the underlying etiology. METHODS: Among the 60,325 patients who underwent colonoscopy at our hospital from January 2006 to December 2018, patients with ulcerative lesions on the ileocecal valve were included. The following data were obtained using the hospital's medical records: sex, age, clinical diagnosis, laboratory data, and endoscopic and histological findings. Patients who have ulcerative colitis and who were not evaluated by histological examination were excluded. Ulcerative lesions on the ileocecal valve were classified into 3 groups according to their endoscopic appearance: small shallow ulcerative lesions without edematous change (group A), lateral spreading shallow ulcerative lesions with edematous change (group B), and deep deformed ulcerative lesions (group C). The association between this endoscopic classification and its clinical diagnosis, clinical course, and the interobserver reliability were evaluated. RESULTS: Of 72 patients who were eligible for analysis, 18 were assigned to group A, 9 to group B, and 45 to group C. Infectious enteritis was mainly assigned to group A (group A, 12; group B, none; and group C, 6; p < 0.0001), inflammatory bowel disease was mainly assigned to group C (group A, none; group B, 5; and group C, 35; p < 0.0001), and malignant tumor was assigned to group C only. Interobserver reliability was extremely high among the 3 examining doctors (kappa value 0.7-0.8). CONCLUSION: Endoscopic classification was divided into 3 groups for ulcerative lesions on the ileocecal valve, and this system could be beneficial for presuming their clinical diagnoses.


Asunto(s)
Colitis Ulcerosa , Válvula Ileocecal , Colitis Ulcerosa/diagnóstico , Colitis Ulcerosa/patología , Colonoscopía , Humanos , Válvula Ileocecal/diagnóstico por imagen , Válvula Ileocecal/patología , Reproducibilidad de los Resultados , Estudios Retrospectivos
5.
BMC Nephrol ; 20(1): 394, 2019 10 29.
Artículo en Inglés | MEDLINE | ID: mdl-31664942

RESUMEN

BACKGROUND: Sebaceous carcinoma is a rare but progressive malignant skin cancer, and the incidence is approximately five times higher in post-transplant patients than in people who have not received kidney transplants. Sebaceous carcinoma is sometimes found concurrently with visceral cancers and a genetic abnormality, Muir-Torre syndrome. We report the case of a female kidney transplant recipient with sebaceous carcinoma concurrent with colon cancer 10 years after transplantation. CASE PRESENTATION: A 43-year-old woman was admitted due to a rapidly progressive tumor on her head. Histologically, the tumor was diagnosed as sebaceous carcinoma. We diagnosed her with Muir-Torre syndrome based on the following evidence: 1) high prevalence of microsatellite instability in gene locus assay, 2) absence of mismatch repair proteins in the sebaceous carcinoma on immunohistochemical analysis, and 3) a genetic mutation of 1226_1227delAG in the MSH2 exon 7 in the lesion detected by DNA sequencing analysis. Several reports have shown an association between immunosuppressive agents and latent Muir-Torre syndrome progression. Therefore, the progression of colon cancer in this case originated from her genetic mutation for Muir-Torre syndrome and long-term use of immunosuppressive agents. CONCLUSION: This case report not only highlights the importance of adequate diagnosis and therapy for Muir-Torre syndrome, but also suggests the further prevention of the development of malignant tumors in kidney transplant recipients. Physicians should be mindful that sebaceous carcinoma in kidney transplant recipients is highly concurrent with Muir-Torre syndrome.


Asunto(s)
Adenocarcinoma/genética , Neoplasias del Colon/genética , Neoplasias de Cabeza y Cuello/genética , Trasplante de Riñón/efectos adversos , Síndrome de Muir-Torre/genética , Neoplasias Cutáneas/genética , Adenocarcinoma/patología , Adulto , Neoplasias del Colon/patología , Proteínas de Unión al ADN/análisis , Femenino , Neoplasias de Cabeza y Cuello/patología , Humanos , Inmunosupresores/efectos adversos , Inestabilidad de Microsatélites , Síndrome de Muir-Torre/patología , Proteína 2 Homóloga a MutS/genética , Mutación , Cuero Cabelludo , Neoplasias Cutáneas/patología , Factores de Tiempo , Receptores de Trasplantes
6.
J Clin Invest ; 128(9): 4132-4147, 2018 08 31.
Artículo en Inglés | MEDLINE | ID: mdl-29990311

RESUMEN

Cyclin D1 is an oncogene frequently overexpressed in human cancers that has a dual function as cell cycle and transcriptional regulator, although the latter is widely unexplored. Here, we investigated the transcriptional role of cyclin D1 in lymphoid tumor cells with cyclin D1 oncogenic overexpression. Cyclin D1 showed widespread binding to the promoters of most actively transcribed genes, and the promoter occupancy positively correlated with the transcriptional output of targeted genes. Despite this association, the overexpression of cyclin D1 in lymphoid cells led to a global transcriptional downmodulation that was proportional to cyclin D1 levels. This cyclin D1-dependent global transcriptional downregulation was associated with a reduced nascent transcription and an accumulation of promoter-proximal paused RNA polymerase II (Pol II) that colocalized with cyclin D1. Concordantly, cyclin D1 overexpression promoted an increase in the Poll II pausing index. This transcriptional impairment seems to be mediated by the interaction of cyclin D1 with the transcription machinery. In addition, cyclin D1 overexpression sensitized cells to transcription inhibitors, revealing a synthetic lethality interaction that was also observed in primary mantle cell lymphoma cases. This finding of global transcriptional dysregulation expands the known functions of oncogenic cyclin D1 and suggests the therapeutic potential of targeting the transcriptional machinery in cyclin D1-overexpressing tumors.


Asunto(s)
Ciclina D1/genética , Ciclina D1/metabolismo , Linfoma de Células del Manto/genética , Linfoma de Células del Manto/metabolismo , Carcinogénesis/genética , Línea Celular Tumoral , Cromatina/genética , Cromatina/metabolismo , Regulación hacia Abajo , Regulación Neoplásica de la Expresión Génica , Código de Histonas , Humanos , Modelos Biológicos , Regiones Promotoras Genéticas , ARN Polimerasa II/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Transcripción Genética
7.
J Neurosci ; 37(41): 9889-9900, 2017 10 11.
Artículo en Inglés | MEDLINE | ID: mdl-28899920

RESUMEN

Neurotransmission plays an essential role in neural circuit formation in the central nervous system (CNS). Although neurotransmission has been recently clarified as a key modulator of retinal circuit development, the roles of individual synaptic transmissions are not yet fully understood. In the current study, we investigated the role of neurotransmission from photoreceptor cells to ON bipolar cells in development using mutant mouse lines of both sexes in which this transmission is abrogated. We found that deletion of the ON bipolar cation channel TRPM1 results in the abnormal contraction of rod bipolar terminals and a decreased number of their synaptic connections with amacrine cells. In contrast, these histological alterations were not caused by a disruption of total glutamate transmission due to loss of the ON bipolar glutamate receptor mGluR6 or the photoreceptor glutamate transporter VGluT1. In addition, TRPM1 deficiency led to the reduction of total dendritic length, branch numbers, and cell body size in AII amacrine cells. Activated Goα, known to close the TRPM1 channel, interacted with TRPM1 and induced the contraction of rod bipolar terminals. Furthermore, overexpression of Channelrhodopsin-2 partially rescued rod bipolar cell development in the TRPM1-/- retina, whereas the rescue effect by a constitutively closed form of TRPM1 was lower than that by the native form. Our results suggest that TRPM1 channel opening is essential for rod bipolar pathway establishment in development.SIGNIFICANCE STATEMENT Neurotransmission has been recognized recently as a key modulator of retinal circuit development in the CNS. However, the roles of individual synaptic transmissions are not yet fully understood. In the current study, we focused on neurotransmission between rod photoreceptor cells and rod bipolar cells in the retina. We used genetically modified mouse models which abrogate each step of neurotransmission: presynaptic glutamate release, postsynaptic glutamate reception, or transduction channel function. We found that the TRPM1 transduction channel is required for the development of rod bipolar cells and their synaptic formation with subsequent neurons, independently of glutamate transmission. This study advances our understanding of neurotransmission-mediated retinal circuit refinement.


Asunto(s)
Células Amacrinas/fisiología , Retina/crecimiento & desarrollo , Células Bipolares de la Retina/fisiología , Células Fotorreceptoras Retinianas Bastones/fisiología , Canales Catiónicos TRPM/fisiología , Vías Visuales/crecimiento & desarrollo , Vías Visuales/fisiología , Animales , Channelrhodopsins , Dendritas/fisiología , Dendritas/ultraestructura , Femenino , Ácido Glutámico/fisiología , Técnicas In Vitro , Masculino , Ratones , Ratones Noqueados , Técnicas de Placa-Clamp , Retina/citología , Transmisión Sináptica/fisiología , Canales Catiónicos TRPM/genética , Proteína 1 de Transporte Vesicular de Glutamato/biosíntesis , Proteína 1 de Transporte Vesicular de Glutamato/genética
8.
Cell Rep ; 10(5): 796-808, 2015 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-25660028

RESUMEN

In vertebrate retinal development, the axonal terminals of retinal neurons make synaptic contacts within narrow fixed regions, and these locations are maintained thereafter. However, the mechanisms and biological logic of the organization of these fixed synapse locations are poorly understood. We show here that a membrane scaffold protein, 4.1G, is highly expressed in retinal photoreceptors and is essential for the arrangement of their correct synapse location. The 4.1G-deficient retina exhibits mislocalization of photoreceptor terminals, although their synaptic connections are normally formed. The 4.1G protein binds to the AP3B2 protein, which is involved in neuronal membrane trafficking, and promotes neurite extension in an AP3B2-dependent manner. 4.1G mutant mice showed visual acuity impairments in an optokinetic response, suggesting that correct synapse location is required for normal visual function. Taken together, the data in this study provide insight into the mechanism and importance of proper synapse location in neural circuit formation.

9.
J Diabetes Sci Technol ; 9(3): 632-8, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25526758

RESUMEN

BACKGROUND: The study presents a comparison of the glucose-lowering effects, glycemic variability, and insulin doses during treatment with insulin degludec or insulin glargine. METHODS: In this open-label, single-center, 2-way crossover study, 13 Japanese diabetic outpatients in the insulin-dependent state on basal-bolus therapy were assigned to receive either insulin glargine followed by insulin degludec, or insulin degludec followed by insulin glargine. Basal insulin doses were fixed in principle, and patients self-adjusted their bolus insulin doses. Seventy-two-hour continuous glucose monitoring was performed 2 weeks after switching the basal insulin. RESULTS: Mean blood glucose (mg/dL) was not significantly different between insulin degludec and insulin glargine over 48 hours (141.8 ± 35.2 vs 151.8 ± 43.3), at nighttime (125.6 ± 40.0 vs 124.7 ± 50.4), or at daytime (149.3 ± 37.1 vs 163.3 ± 44.5). The standard deviation (mg/dL) was also similar (for 48 hours: 48.9 ± 19.4 vs 50.3 ± 17.3; nighttime: 18.7 ± 14.3 vs 13.7 ± 6.7; daytime: 49.3 ± 20.0 vs 44.3 ± 17.7). Other indices of glycemic control, glycemic variability, and hypoglycemia were similar for both insulin analogs. Total daily insulin dose (TDD) and total daily bolus insulin dose (TDBD) were significantly lower with insulin degludec than with insulin glargine (TDD: 0.42 ± 0.20 vs 0.46 ± 0.22 U/kg/day, P = .028; TDBD: 0.27 ± 0.13 vs 0.30 ± 0.14 U/kg/day, P = .036). CONCLUSIONS: Insulin degludec and insulin glargine provided effective and stable glycemic control. Insulin degludec required lower TDD and TDBD in this population of patients.


Asunto(s)
Diabetes Mellitus Tipo 1/tratamiento farmacológico , Hipoglucemiantes/administración & dosificación , Hipoglucemiantes/uso terapéutico , Insulina Glargina/administración & dosificación , Insulina Glargina/uso terapéutico , Insulina de Acción Prolongada/administración & dosificación , Insulina de Acción Prolongada/uso terapéutico , Pueblo Asiatico , Glucemia/análisis , Estudios Cruzados , Humanos , Hipoglucemia/inducido químicamente , Hipoglucemia/epidemiología , Hipoglucemiantes/efectos adversos , Insulina Glargina/efectos adversos , Insulina de Acción Prolongada/efectos adversos
10.
J Immunol ; 193(9): 4322-4334, 2014 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-25230751

RESUMEN

Dendritic cells (DCs), macrophages (MPs), and monocytes are permissive to HIV. Whether they similarly process and present HIV epitopes to HIV-specific CD8 T cells is unknown despite the critical role of peptide processing and presentation for recognition and clearance of infected cells. Cytosolic peptidases degrade endogenous proteins originating from self or pathogens, exogenous Ags preprocessed in endolysosomes, thus shaping the peptidome available for endoplasmic reticulum translocation, trimming, and MHC-I presentation. In this study, we compared the capacity of DCs, MPs, and monocyte cytosolic extracts to produce epitope precursors and epitopes. We showed differences in the proteolytic activities and expression levels of cytosolic proteases between monocyte-derived DCs and MPs and upon maturation with LPS, R848, and CL097, with mature MPs having the highest activities. Using cytosol as a source of proteases to degrade epitope-containing HIV peptides, we showed by mass spectrometry that the degradation patterns of long peptides and the kinetics and amount of antigenic peptides produced differed among DCs, MPs, and monocytes. Additionally, variable intracellular stability of HIV peptides prior to loading onto MHC may accentuate the differences in epitope availability for presentation by MHC-I between these subsets. Differences in peptide degradation led to 2- to 25-fold differences in the CTL responses elicited by the degradation peptides generated in DCs, MPs, and monocytes. Differences in Ag-processing activities between these subsets might lead to variations in the timing and efficiency of recognition of HIV-infected cells by CTLs and contribute to the unequal capacity of HIV-specific CTLs to control viral load.


Asunto(s)
Presentación de Antígeno/inmunología , Células Dendríticas/inmunología , Epítopos/inmunología , Infecciones por VIH/inmunología , VIH/inmunología , Macrófagos/inmunología , Monocitos/inmunología , Linfocitos T Citotóxicos/inmunología , Secuencia de Aminoácidos , Animales , Antígenos de Superficie/metabolismo , Línea Celular Transformada , Citosol/inmunología , Citosol/metabolismo , Células Dendríticas/metabolismo , Humanos , Inmunofenotipificación , Leucocitos Mononucleares/inmunología , Leucocitos Mononucleares/metabolismo , Macrófagos/metabolismo , Monocitos/metabolismo , Péptido Hidrolasas/metabolismo , Péptidos/química , Péptidos/inmunología , Complejo de la Endopetidasa Proteasomal/metabolismo , Estabilidad Proteica , Proteolisis , Linfocitos T Citotóxicos/metabolismo , Receptores Toll-Like/metabolismo
11.
J Immunol ; 192(8): 3496-506, 2014 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-24616479

RESUMEN

Ag processing by intracellular proteases and peptidases and epitope presentation are critical for recognition of pathogen-infected cells by CD8+ T lymphocytes. First-generation HIV protease inhibitors (PIs) alter proteasome activity, but the effect of first- or second-generation PIs on other cellular peptidases, the underlying mechanism, and impact on Ag processing and epitope presentation to CTL are still unknown. In this article, we demonstrate that several HIV PIs altered not only proteasome but also aminopeptidase activities in PBMCs. Using an in vitro degradation assay involving PBMC cytosolic extracts, we showed that PIs altered the degradation patterns of oligopeptides and peptide production in a sequence-specific manner, enhancing the cleavage of certain residues and reducing others. PIs affected the sensitivity of peptides to intracellular degradation, and altered the kinetics and amount of HIV epitopes produced intracellularly. Accordingly, the endogenous degradation of incoming virions in the presence of PIs led to variations in CTL-mediated killing of HIV-infected cells. By altering host protease activities and the degradation patterns of proteins in a sequence-specific manner, HIV PIs may diversify peptides available for MHC class I presentation to CTL, alter the patterns of CTL responses, and provide a complementary approach to current therapies for the CTL-mediated clearance of abnormal cells in infection, cancer, or other immune disease.


Asunto(s)
Aminopeptidasas/metabolismo , Presentación de Antígeno/efectos de los fármacos , Presentación de Antígeno/inmunología , Epítopos de Linfocito T/inmunología , Epítopos de Linfocito T/metabolismo , Inhibidores de la Proteasa del VIH/farmacología , Secuencia de Aminoácidos , Linfocitos T CD8-positivos/efectos de los fármacos , Linfocitos T CD8-positivos/enzimología , Linfocitos T CD8-positivos/inmunología , Activación Enzimática/efectos de los fármacos , Epítopos de Linfocito T/química , VIH-1/inmunología , Humanos , Espacio Intracelular/metabolismo , Complejo de la Endopetidasa Proteasomal/efectos de los fármacos , Complejo de la Endopetidasa Proteasomal/metabolismo , Estabilidad Proteica , Proteolisis , Linfocitos T Citotóxicos/efectos de los fármacos , Linfocitos T Citotóxicos/enzimología , Linfocitos T Citotóxicos/inmunología
12.
BMC Cell Biol ; 14: 35, 2013 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-23937268

RESUMEN

BACKGROUND: Endolysosomes play a key role in maintaining the homeostasis of the cell. They are made of a complex set of proteins that degrade lipids, proteins and sugars. Studies involving endolysosome contribution to cellular functions such as MHC class I and II epitope production have used recombinant endolysosomal proteins, knockout mice that lack one of the enzymes or purified organelles from human tissue. Each of these approaches has some caveats in analyzing endolysosomal enzyme functions. RESULTS: In this study, we have developed a simple methodology to assess endolysosomal protease activity. By varying the pH in crude lysate from human peripheral blood mononuclear cells (PBMCs), we documented increased endolysosomal cathepsin activity in acidic conditions. Using this new method, we showed that the degradation of HIV peptides in low pH extracts analyzed by mass spectrometry followed similar kinetics and degradation patterns as those performed with purified endolysosomes. CONCLUSION: By using crude lysate in the place of purified organelles this method will be a quick and useful tool to assess endolysosomal protease activities in primary cells of limited availability. This quick method will especially be useful to screen peptide susceptibility to degradation in endolysosomal compartments for antigen processing studies, following which detailed analysis using purified organelles may be used to study specific peptides.


Asunto(s)
Presentación de Antígeno/fisiología , Leucocitos Mononucleares/inmunología , Lisosomas/enzimología , Espectrometría de Masas/métodos , Péptido Hidrolasas/metabolismo , Secuencia de Aminoácidos , Antígenos/metabolismo , Catepsinas/metabolismo , Células Cultivadas , Humanos , Concentración de Iones de Hidrógeno , Leucocitos Mononucleares/citología , Leucocitos Mononucleares/metabolismo , Datos de Secuencia Molecular , Proteínas/metabolismo
13.
J Immunol ; 188(12): 5924-34, 2012 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-22586036

RESUMEN

Viruses evade immune detection partly through immune-associated mutations. Analyses of HIV sequences derived from infected individuals have identified numerous examples of HLA-associated mutations within or adjacent to T cell epitopes, but the potential impact of most mutations on epitope production and presentation remains unclear. The multistep breakdown of proteins into epitopes includes trimming of N-extended peptides into epitopes by aminopeptidases before loading onto MHC class I molecules. Definition of sequence signatures that modulate epitope production would lead to a better understanding of factors driving viral evolution and immune escape at the population level. In this study, we identified cytosolic aminopeptidases cleavage preferences in primary cells and its impact on HIV Ag degradation into epitopes in primary human cell extracts by mass spectrometry and on epitope presentation to CTL. We observed a hierarchy of preferred amino acid cleavage by cytosolic aminopeptidases. We demonstrated that flanking mutations producing more or less cleavable motifs can increase or decrease epitope production and presentation by up to 14-fold. We found that the efficiency of epitope production correlates with cleavability of flanking residues. These in vitro findings were supported by in vivo population-level analyses of clinically derived viral sequences from 1134 antiretroviral-naive HIV-infected individuals: HLA-associated mutations immune pressures drove the selection of residues that are less cleavable by aminopeptidases predominantly at N-flanking sites, leading to reduced epitope production and immune recognition. These results underscore an important and widespread role of Ag processing mutations in HIV immune escape and identify molecular mechanisms underlying impaired epitope presentation.


Asunto(s)
Aminopeptidasas/inmunología , Presentación de Antígeno/inmunología , Epítopos de Linfocito T/inmunología , Infecciones por VIH/inmunología , Proteínas del Virus de la Inmunodeficiencia Humana/inmunología , Evasión Inmune/inmunología , Aminopeptidasas/genética , Aminopeptidasas/metabolismo , Presentación de Antígeno/genética , Separación Celular , Epítopos de Linfocito T/metabolismo , Citometría de Flujo , Infecciones por VIH/genética , Infecciones por VIH/metabolismo , Antígenos de Histocompatibilidad Clase I/inmunología , Proteínas del Virus de la Inmunodeficiencia Humana/metabolismo , Humanos , Evasión Inmune/genética , Activación de Linfocitos/genética , Activación de Linfocitos/inmunología , Mutación
14.
Asian J Sports Med ; 3(1): 47-52, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22461965

RESUMEN

PURPOSE: T1WI (T1 weighted image) was acquired in order to grade bone fusion following the studies by FIFA (Federation Internationale de Football Associations). Research using images other than T1WI has not been reported. The aim of this study is to evaluate the grade of epiphyseal fusion by T2* weighted images (T2*WI) and to investigate new findings on T2*WI as compared with T1WI. METHODS: A total of 87 subjects, all junior football players between the ages of 12 and 17 years old, were examined. T1 and T2* WI were obtained using a 1.2T Open type MR system. The T1WI and T2*WI were rated twice randomly by four radiologists using the FIFA grading system. RESULTS: The intra-rater reliability for grading was higher in T1WI (The Intraclass Correlation Coefficient (ICC)=0.949-0.985) than in T2*WI (ICC=0.917-0.943). The inter-rater reliability for grading was also higher in T1WI (ICC=0.923) than in T2*WI (ICC=0.867). CONCLUSIONS: This research showed that T1WI is a better sequence than T2*WI to evaluate bone fusion following FIFA protocol. It was speculated that the reason for this is that T1WI has higher tissue contrast resolution and enables clearer images of the epiphyseal fusion than T2*WI and the grading system by T1WI was not suitable for T2*WI.

15.
Appl Microbiol Biotechnol ; 86(2): 641-8, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19894045

RESUMEN

In modern industrial society, molybdenum is one of the important metals for development of the industry of rare metals. It is important to recycle the rare metals from wastes because they are technically and economically difficult to be dug and be purified, and they exist in only a few regions in the world. In this study, ModE protein derived from Escherichia coli, which is a molybdate-dependent transcriptional regulator with the ability to bind molybdate as a form of soluble molybdenum, was displayed on the yeast cell surface by alpha-agglutinin-based cell surface display system for the adsorption and recovery of molybdate. Displayed ModE, confirmed by immunofluorescence labeling, caught molybdate more preferably at pH 3.0 than at basic pH. Yeast cells displaying C-terminal domain of ModE, which lacks N-terminal DNA binding domain, more effectively adsorbed molybdate than those displaying full-length ModE, suggesting that the deletion of the domain unrelated to metal binding enhanced the binding ability. Our results indicated that the adsorption system on cell surface of yeast cells displaying ModE is effective not only for adsorption of molybdate as a rare metal bioadsorbent but also for the easy recovery of molybdate located on the cell surface.


Asunto(s)
Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Molibdeno/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Concentración de Iones de Hidrógeno , Unión Proteica , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Eliminación de Secuencia
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