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1.
PLoS One ; 17(7): e0271205, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35816501

RESUMEN

Recent studies demonstrate that immune checkpoint blockade (ICB) increases the chances of the abscopal effect, an anti-tumor effect outside the radiation field in radiation therapy. However, the optimal sequence between radiation and ICB remains unclear. To investigate the impact of sequence of radiation in anti-PD-L1 antibody (P1) therapy on immune microenvironments and antitumor efficacies in local and abscopal tumors, metastatic LM8 osteosarcoma cells were inoculated into both legs of C3H mice. For irradiation, only one side leg was irradiated at 10 Gy. Then mice were divided into four groups: administrated anti-PD-L1 antibody three times (P1 monotherapy), receiving radiation 3 days prior to P1 therapy (P1+pre-Rad), and receiving concurrent radiation with P1 therapy (P1+conc-Rad). Thereafter, tumor immune microenvironment and tumor volume changes were analyzed in irradiated and unirradiated tumors. The P1+pre-Rad regimen increased the proportion of CD8+ programmed cell death 1 (PD-1)+ granzyme B (GzmB)+ reinvigorated T cells and decreased the proportion of CD8+ PD-1+ GzmB- exhausted T cells than P1+conc-Rad regimen in unirradiated tumors. Combination regimens suppressed tumor growth in irradiated tumors compared with that in P1 monotherapy. In both irradiated and unirradiated tumors, significant tumor growth suppression and prolonged overall survival were observed under both combination treatment regimens compared with P1 monotherapy. However, no distinct differences in unirradiated tumor volume and survival were observed between P1+pre-Rad and P1+conc-Rad groups. These results suggest that local irradiation is necessary to improve systemic treatment efficacy in P1 therapy regardless of sequence of local irradiation.


Asunto(s)
Neoplasias Óseas , Osteosarcoma , Animales , Neoplasias Óseas/radioterapia , Linfocitos T CD8-positivos , Línea Celular Tumoral , Inmunoterapia/métodos , Ratones , Ratones Endogámicos C3H , Osteosarcoma/tratamiento farmacológico , Osteosarcoma/radioterapia , Receptor de Muerte Celular Programada 1 , Microambiente Tumoral
2.
Asia Pac J Ophthalmol (Phila) ; 11(3): 279-286, 2022 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-35772086

RESUMEN

PURPOSE: To investigate the longitudinal changes in the peripapillary retinal nerve fiber layer (pRNFL) thickness after epiretinal membrane (ERM) vitrectomy with internal limiting membrane (ILM) peeling, examine associations between pRNFL thickness and central retinal sensitivity, and identify predictors of postoperative pRNFL thickness. DESIGN: Prospective, observational, cohort study. METHODS: This study enrolled 82 eyes of 82 Japanese patients that underwent surgery for unilateral idiopathic ERM, with their fellow eyes as controls. pRNFL thickness was measured in 4 (superior, temporal, inferior, and nasal) quadrants preoperatively and at 1, 3, 6, and 12 months postoperatively. Microperimetry was performed at 12 months postoperatively to evaluate central retinal sensitivity. Regression tree analysis was performed to predict pRNFL thickness at 12 months postoperatively. RESULTS: The temporal quadrant showed continuous pRNFL thinning after surgery, reaching statistical significance at 3, 6, and 12 months postoperatively (all P < 0.001). The pRNFL thicknesses in the fellow eyes significantly increased at all postoperative time points (all P < 0.001). At 12 months postoperatively, the average central retinal sensitivity was significantly correlated with the temporal pRNFL thickness in the eyes with ERM (r = 0.372, P < 0.001); no significant correlation was found in the fellow eyes. Regression tree analysis showed that the preoperative pRNFL thickness in the temporal quadrant and patient age were the main determinants of the temporal pRNFL thickness at 12 months postoperatively. CONCLUSIONS: The risk of deterioration of central retinal sensitivity after ERM vitrectomy with internal limiting membrane peeling should be considered for patients with thin temporal pRNFLs and older adults.


Asunto(s)
Membrana Epirretinal , Anciano , Estudios de Cohortes , Membrana Epirretinal/cirugía , Humanos , Lactante , Fibras Nerviosas , Estudios Prospectivos , Células Ganglionares de la Retina , Estudios Retrospectivos , Tomografía de Coherencia Óptica , Vitrectomía
3.
Cancers (Basel) ; 14(9)2022 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-35565217

RESUMEN

Pancreatic cancer is an extremely treatment-resistant neoplasm to chemotherapy and immunotherapy. The combination of photon beam irradiation and anti-CTLA-4 antibody (C4) for the anti-tumor effect enhancement at local and distant tumors (abscopal tumors) was investigated using the pancreatic ductal adenocarcinoma (PDAC) mouse model. Pan02 cells were bilaterally inoculated to both legs of C57BL/6 mice. High dose photon beams in a hypofractionation or a single fraction were delivered to the tumors on one leg. Monotherapy with C4 via i.p. was not effective for PDAC. The high dose irradiation to the local tumors produced significant shrinkage of irradiated tumors but did not induce the abscopal responses. In contrast, the combination therapy of high dose photon beam irradiation in both hypofractionation and a single fraction with C4 enhanced the anti-tumor effect for abscopal tumors with significantly prolonged overall survival. The flow cytometric analysis revealed that the combination therapy dramatically decreased the regulatory T cell (Treg) proportion while increasing the cytotoxic T lymphocytes in both local and abscopal tumors. These results suggest that high dose photon beam irradiation plays an important role in C4 therapy to enhance the abscopal response with immune microenvironment changes in PDAC, regardless of the fractionation in radiation therapy.

4.
DNA Res ; 29(3)2022 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-35608323

RESUMEN

Partial bacterial genome reduction by genome engineering can improve the productivity of various metabolites, possibly via deletion of non-essential genome regions involved in undesirable metabolic pathways competing with pathways for the desired end products. However, such reduction may cause growth defects. Genome reduction of Bacillus subtilis MGB874 increases the productivity of cellulases and proteases but reduces their growth rate. Here, we show that this growth defect could be restored by silencing redundant or less important genes affecting exponential growth by manipulating the global transcription factor AbrB. Comparative transcriptome analysis revealed that AbrB-regulated genes were upregulated and those involved in central metabolic pathway and synthetic pathways of amino acids and purine/pyrimidine nucleotides were downregulated in MGB874 compared with the wild-type strain, which we speculated were the cause of the growth defects. By constitutively expressing high levels of AbrB, AbrB regulon genes were repressed, while glycolytic flux increased, thereby restoring the growth rate to wild-type levels. This manipulation also enhanced the productivity of metabolites including γ-polyglutamic acid. This study provides the first evidence that undesired features induced by genome reduction can be relieved, at least partly, by manipulating a global transcription regulation system. A similar strategy could be applied to other genome engineering-based challenges aiming toward efficient material production in bacteria.


Asunto(s)
Bacillus subtilis , Proteínas Bacterianas , Bacillus subtilis/genética , Bacillus subtilis/metabolismo , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Regulación de la Expresión Génica , Regulación Bacteriana de la Expresión Génica , Genoma Bacteriano , Factores de Transcripción/genética , Factores de Transcripción/metabolismo
5.
Front Med (Lausanne) ; 9: 827388, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35280914

RESUMEN

Background: Autoimmune tubulointerstitial nephritis (TIN) is characterized by immune-mediated tubular injury and requires immunosuppressive therapy. However, diagnosing TIN and assessing therapeutic response are challenging for clinicians due to the lack of useful biomarkers. Pathologically, CD4+ T cells infiltrate to renal tubulointerstitium, and soluble interleukin-2 receptor (sIL-2R) has been widely known as a serological marker of activated T cell. Here, we explored the usefulness of serum sIL-2R to predict the treatment outcome in patients with autoimmune TIN. Methods: Study Design: Single-center retrospective observational study. Participants: 62 patients were diagnosed of TIN from 2005 to April 2018 at Hokkaido University Hospital. Among them, 30 patients were diagnosed with autoimmune TIN and treated with corticosteroids. We analyzed the association between baseline characteristics including sIL-2R and the change of estimated glomerular filtration rate (eGFR) after initiation of corticosteroids. Results: The serum sIL-2R level in patients with autoimmune TIN was significantly higher than that in chronic kidney disease patients with other causes. Mean eGFR in autoimmune TIN patients treated with corticosteroids increased from 43.3 ± 20.4 mL/min/1.73 m2 (baseline) to 50.7 ± 19.9 mL/min/1.73 m2 (3 months) (ΔeGFR; 22.8 ± 26.0%). Multivariate analysis revealed that higher sIL-2R (per 100 U/mL, ß = 1.102, P < 0.001) level was independently associated with the renal recovery. In ROC analysis, sIL-2R had the best area under the curve value (0.805) and the cutoff point was 1182 U/mL (sensitivity = 0.90, 1-specificity = 0.45). Conclusions: Our study showed that elevated serum sIL-2R levels might become a potential predictive marker for therapeutic response in autoimmune TIN.

6.
J Phys Chem B ; 126(9): 1868-1875, 2022 03 10.
Artículo en Inglés | MEDLINE | ID: mdl-35213155

RESUMEN

Conformational fluctuation, namely, protein interconversion between different conformations, is crucial to protein function. Outer surface protein A (OspA), comprising N- and C-terminal globular domains linked by a central ß-sheet, is expressed on the surface of Borrelia burgdorferi, the causative agent of Lyme disease, and recognizes the TROSPA receptor in the tick gut. Solution nuclear magnetic resonance studies have shown that the central ß-sheet and C-terminal domain containing TROSPA recognition sites are less stable than the N-terminal domain, revealing an intermediate conformation between the basic folded and completely unfolded proteins. We previously suggested that exposure of receptor-binding sites following denaturation of the C-terminal domain is advantageous for OspA binding to the receptor. Here, we observed amplification of a specific protein fluctuation by pressure perturbation and site-specific mutagenesis. The salt-bridge-destabilized mutant E160D and the cavity-enlarged mutant I243A favored the intermediate. The proportion of the intermediate accounted for almost 100% in E160D at 250 MPa. Strategies using a suitably chosen point mutation with high pressure are generally applicable for amplification of specific conformational fluctuation and potentially improve our understanding of the intermediate conformations of proteins. Knowledge of various conformations, including OspA intermediates, may be useful for designing a vaccine for Lyme disease.


Asunto(s)
Borrelia burgdorferi , Enfermedad de Lyme , Proteínas de la Membrana Bacteriana Externa/química , Proteínas de la Membrana Bacteriana Externa/genética , Borrelia burgdorferi/química , Borrelia burgdorferi/genética , Borrelia burgdorferi/metabolismo , Humanos , Presión Hidrostática , Mutagénesis Sitio-Dirigida , Conformación Proteica en Lámina beta
7.
Can J Ophthalmol ; 57(2): 82-89, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-33727104

RESUMEN

OBJECTIVE: To investigate the refractive change and optical biometry dynamics after 25-gauge vitrectomy without gas tamponade for macular pathology in pseudophakic eyes. DESIGN: A prospective observational case series. PARTICIPANTS: Patients with pseudophakic eyes who were scheduled for vitrectomy owing to macular pathology by an experienced surgeon (T.S.) at the Hayashi Eye Hospital between March 2019 and February 2020. METHODS: The primary endpoint was the change in manifest refraction spherical equivalent (MRSE) between baseline (preoperatively) and 3 months postoperatively. The secondary endpoint was the change in optical biometry parameters obtained by swept-source optical coherence tomography-based biometers between baseline and 3 months postoperatively. Optical biometry parameters included corneal curvature and axial length, evaluated by the IOLMaster 700, and intraocular lens position-that is, lens decentration, lens tilt, and aqueous depth (AQD)-evaluated by the CASIA2. RESULTS: Thirty-four eyes of 34 patients were enrolled. The mean MRSE values at baseline and 3 months postoperatively were -0.70 ± 1.21 diopter (D) and -0.82 ± 1.27 D, respectively, showing a significant myopic shift of -0.12 ± 0.41 D postoperatively (p = 0.043). There was no significant difference between the pre- and postoperative values of the optical biometry parameters, except for the AQD (4.28 ± 0.34 mm vs 4.27 ± 0.34 mm; p = 0.019). CONCLUSIONS: The results suggest that replacing the vitreous by the aqueous during vitrectomy induces an average myopic shift of -0.12 D.


Asunto(s)
Cristalino , Lentes Intraoculares , Biometría/métodos , Ojo , Humanos , Refracción Ocular , Vitrectomía/métodos
8.
Medicine (Baltimore) ; 100(50): e27778, 2021 Dec 17.
Artículo en Inglés | MEDLINE | ID: mdl-34918629

RESUMEN

ABSTRACT: Immunoglobulin A nephropathy (IgAN) is a form of chronic glomerulonephritis that can cause end-stage renal disease. Recently, tonsillectomy combined with corticosteroid pulse (TSP) has been shown to be effective for achieving clinical remission and favorable renal outcome in patients with IgAN. However, the standard regimen of corticosteroid use in TSP has not been established. Herein, we compared the effect of single- or triple-course steroid pulse therapy combined with tonsillectomy in patients with IgAN.This retrospective, observational cohort study included 122 patients with IgAN enrolled from January 2004 to December 2018 at 2 independent institutions. We divided the patients into 2 groups; single-course (TSP1: n = 70) and triple-course (TSP3: n = 52) of corticosteroid pulse therapy (1 course comprised 3 consecutive days' infusion of 0.5 g methylprednisolone) combined with tonsillectomy. The primary outcome for renal survival was defined as the first occurrence of ≧30% decrease in estimated glomerular filtration rate from baseline. Secondary outcomes included the incidence of clinical remission and recurrence of the disease.Regarding clinical parameters and findings at baseline, there were no significant differences between the 2 groups. The 8-years renal survival in the 2 groups was not significantly different according to Kaplan-Meier curves (TSP1; 82.5% vs TSP3; 69.2%, log-rank test P = .39). The cumulative incidence rates of remission of hematuria (94.4% vs 85.4%, P = .56) and clinical remission (85.0% vs 64.8%, P = .07) were comparable in both groups, while those of proteinuria showed higher rates in TSP1 than TSP3 (88.4% vs 65.4%, P = .02). The cumulative incidence of relapse of hematuria (5.6% vs 2.3%, P = .42) and proteinuria (7.1% vs 3.3%, P = .41) showed no significant differences in the 2 groups. Cox regression analyses showed that the number of courses of corticosteroid pulse therapy was not significantly associated with renal outcome (TSP1 vs TSP3; Hazard ratios 0.69, 95% confidence intervals 0.29-1.64, P = .39).The effect of single-course corticosteroid pulse therapy is not statistically, significantly different from triple-course in TSP protocol for improving renal outcome and preventing relapse in patients with IgAN. Single-course corticosteroid pulse therapy may become a treatment option for patients with IgAN.


Asunto(s)
Corticoesteroides/uso terapéutico , Glomerulonefritis por IGA/tratamiento farmacológico , Glomerulonefritis por IGA/cirugía , Metilprednisolona/uso terapéutico , Quimioterapia por Pulso/métodos , Tonsilectomía , Corticoesteroides/administración & dosificación , Adulto , Femenino , Hematuria , Humanos , Masculino , Metilprednisolona/administración & dosificación , Persona de Mediana Edad , Proteinuria , Recurrencia , Inducción de Remisión , Estudios Retrospectivos , Esteroides/uso terapéutico , Resultado del Tratamiento
9.
Asian Spine J ; 15(1): 9-16, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32693445

RESUMEN

STUDY DESIGN: Prospective cohort study. PURPOSE: This study aims to examine changes in spinopelvic alignment, sagittal global balance, and low back pain (LBP) following the removal of knee flexion contracture by total knee arthroplasty (TKA). OVERVIEW OF LITERATURE: The limitation of the knee extension was correlated with the decrease in lumbar lordosis (LL). Currently, there are no studies evaluating the spinopelvic alignment and LBP before and after TKAs. METHODS: Sagittal spinopelvic alignment was evaluated in 110 subjects using radiographs of the whole spine. Parameters measured in this study included sagittal vertical axis (SVA), LL, sacral slope (SS), pelvic tilt (PT), and pelvic incidence (PI). The distribution of sagittal plane modifier grade was evaluated according to the Scoliosis Research Society-Schwab classification of adult spinal deformity (ASD). Consequently, personal history related to LBP was obtained, and the association of pre- and postoperative LBP and spinopelvic alignment was investigated. RESULTS: Preoperatively, 66% of all subjects showed LBP and mostly exhibited anteriorly shifted global imbalance associated with a decrease in LL and knee flexion contractures, and the subject who had severe flexion contracture of the knee joint showed more forwardly shifted global balance with backward PT and decrease in LL. After TKAs, the knee flexion contractures were eliminated in most cases, and one-third of subjects experienced decrease in LBP. However, SVA increased more and associated with slight decrease of PT and increase of SS. No significant differences were confirmed between pre- and postoperative values of LL and PI. In addition, there were no significant differences in postoperative values of spinopelvic parameters between subjects with and without relieved LBP. CONCLUSIONS: Although one-third of subjects experienced decrease of LBP after TKAs, the sagittal global imbalance was not restored through the removal of knee flexion contracture.

11.
Ther Apher Dial ; 24(2): 146-153, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31210004

RESUMEN

Adynamic bone disease in HD patients is characterized by skeletal resistance to parathyroid hormone (PTH) or suppression of PTH release, leading to a downregulated bone turnover and bone fracture. Hence, we examined the efficacy of weekly teriparatide for HD patients with low PTH indicating adynamic bone disease without a history of parathyroidectomy. Fifteen HD patients with low PTH were recruited in this prospective observational study. Of them, 10 received teriparatide for 12 months and five nontreated patients were enrolled as control. Primary outcomes were defined as the changes in bone mineral density and bone turnover markers. Bone mineral density at the lumbar spine increased by 3.7% and 2.5% at 6 and 12 months, respectively, and bone formation markers increased, while bone resorption markers did not change in the teriparatide group. At 12 months after teriparatide administration, endogenous PTH was secreted followed by the recovery of low bone turnover. 40% of patients in the teriparatide group dropped out due to adverse events and the most common adverse event was transient hypotension. This study suggests that weekly teriparatide for HD patients with low PTH in the absence of parathyroidectomy accelerates bone formation and bone turnover, leading to increased trabecular bone mass and secretion of endogenous PTH.


Asunto(s)
Densidad Ósea/efectos de los fármacos , Trastorno Mineral y Óseo Asociado a la Enfermedad Renal Crónica/tratamiento farmacológico , Hormona Paratiroidea/sangre , Teriparatido/administración & dosificación , Anciano , Anciano de 80 o más Años , Conservadores de la Densidad Ósea/administración & dosificación , Conservadores de la Densidad Ósea/efectos adversos , Remodelación Ósea/efectos de los fármacos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Proyectos Piloto , Estudios Prospectivos , Diálisis Renal , Insuficiencia Renal Crónica/complicaciones , Insuficiencia Renal Crónica/terapia , Teriparatido/efectos adversos , Resultado del Tratamiento
12.
FEBS Open Bio ; 8(9): 1524-1543, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-30186752

RESUMEN

Overnight fasting is a routine procedure before surgery in clinical settings. Intermittent fasting is the most common diet/fitness trend implemented for weight loss and the treatment of lifestyle-related diseases. In either setting, the effects not directly related to parameters of interest, either beneficial or harmful, are often ignored. We previously demonstrated differential activation of cellular adaptive responses in 13 atrophied/nonatrophied organs of fasted mice by quantitative PCR analysis of gene expression. Here, we investigated 2-day fasting-induced protein remodeling in six major mouse organs (liver, kidney, thymus, spleen, brain, and testis) using two-dimensional difference gel electrophoresis (2D DIGE) proteomics as an alternative means to examine systemic adaptive responses. Quantitative analysis of protein expression followed by protein identification using matrix-assisted laser desorption ionization-time-of-flight mass spectrometry (MALDI-TOFMS) revealed that the expression levels of 72, 26, and 14 proteins were significantly up- or downregulated in the highly atrophied liver, thymus, and spleen, respectively, and the expression levels of 32 proteins were up- or downregulated in the mildly atrophied kidney. Conversely, there were no significant protein expression changes in the nonatrophied organs, brain and testis. Upstream regulator analysis highlighted transcriptional regulation by peroxisome proliferator-activated receptor alpha (PPARα) in the liver and kidney and by tumor protein/suppressor p53 (TP53) in the thymus, spleen, and liver. These results imply of the existence of both common and distinct adaptive responses between major mouse organs, which involve transcriptional regulation of specific protein expression upon short-term fasting. Our data may be valuable in understanding systemic transcriptional regulation upon fasting in experimental animals.

13.
Beilstein J Org Chem ; 14: 1192-1202, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29977386

RESUMEN

In this study, six-membered N-acyliminium ions were generated by the "indirect cation pool" method and reacted with several nucleophiles. These reactions afforded disubstituted piperidine derivatives with high diastereoselectivities and good to excellent yields. The conformations of the obtained N-acyliminium ions were studied by low temperature NMR analyses and DFT calculations and were found to be consistent with the Steven's hypothesis.

14.
J Gen Appl Microbiol ; 64(3): 103-107, 2018 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-29526925

RESUMEN

The marine bacterium Rhodovulum sulfidophilum is a nonsulfur phototrophic bacterium, which is known to produce extracellular nucleic acids in soluble form in culture medium. In the present paper, constructing the response regulator ctrA-deficient mutant of R. sulfidophilum, we found that this mutation causes a significant decrease in the extracellular DNA production. However, by the introduction of a plasmid containing the wild type ctrA gene into the mutant, the amount of extracellular DNA produced was recovered. This is the first and clear evidence that the extracellular DNA production is actively controlled by the CtrA in R. sulfidophilum.


Asunto(s)
Proteínas Bacterianas/genética , ADN Bacteriano/biosíntesis , Espacio Extracelular/metabolismo , Regulación Bacteriana de la Expresión Génica/genética , Rhodovulum/genética , Rhodovulum/metabolismo , Organismos Acuáticos/genética , Organismos Acuáticos/metabolismo , ADN Bacteriano/metabolismo , Prueba de Complementación Genética , Mutagénesis Insercional , Plásmidos/genética , Factores de Transcripción/genética , Factores de Transcripción/metabolismo
15.
ACS Omega ; 3(8): 9729-9737, 2018 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-31459102

RESUMEN

In this work, we disclose an advanced general process for the synthesis of tailor-made α-amino acids (α-AAs) via tandem alkylation-second-order asymmetric transformation. The first step is the alkylation of the chiral Ni(II) complex of glycine Schiff base, which is conducted under mild phase-transfer conditions allowing the structural construction of target α-AAs. The second step is based on the methodologically rare second-order asymmetric transformation, resulting in nearly complete precipitation of the corresponding (SC,RN,RC)-configured diastereomer, which can be collected by a simple filtration. The operational convenience and potential scalability of all experimental procedures, coupled with excellent stereochemical outcome, render this method of high synthetic value for the preparation of various tailor-made α-AAs.

16.
Kidney Int ; 92(2): 377-387, 2017 08.
Artículo en Inglés | MEDLINE | ID: mdl-28341273

RESUMEN

Autosomal dominant polycystic kidney disease (ADPKD) is characterized by the progressive development of kidney and liver cysts. The mammalian target of rapamycin (mTOR) cascade is one of the important pathways regulating cyst growth in ADPKD. Branched-chain amino acids (BCAAs), including leucine, play a crucial role to activate mTOR pathway. Therefore, we administered BCAA dissolved in the drinking water to Pkd1flox/flox:Mx1-Cre (cystic) mice from four to 22 weeks of age after polyinosinic-polycytidylic acid-induced conditional Pkd1 knockout at two weeks of age. The BCAA group showed significantly greater kidney/body weight ratio and higher cystic index in both the kidney and liver compared to the placebo-treated mice. We found that the L-type amino acid transporter 1 that facilitates BCAA entry into cells is strongly expressed in cells lining the cysts. We also found increased cyst-lining cell proliferation and upregulation of mTOR and mitogen-activated protein kinase/extracellular signal-regulated kinase (MAPK/ERK) pathways in the BCAA group. In vitro, we cultured renal epithelial cell lines from Pkd1 null mice with or without leucine. Leucine was found to stimulate cell proliferation, as well as activate mTOR and MAPK/ERK pathways in these cells. Thus, BCAA accelerated disease progression by mTOR and MAPK/ERK pathways. Hence, BCAA may be harmful to patients with ADPKD.


Asunto(s)
Aminoácidos de Cadena Ramificada/toxicidad , Modelos Animales de Enfermedad , Sistema de Señalización de MAP Quinasas , Riñón Poliquístico Autosómico Dominante/inducido químicamente , Serina-Treonina Quinasas TOR/metabolismo , Animales , Ratones , Riñón Poliquístico Autosómico Dominante/genética , Riñón Poliquístico Autosómico Dominante/metabolismo
17.
Plant Cell Physiol ; 58(2): 279-286, 2017 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-27837093

RESUMEN

Cyanobacteria exhibit light-dependent cell growth since most of their cellular energy is obtained by photosynthesis. In Synechococcus elongatus PCC 7942, one of the model cyanobacteria, DNA replication depends on photosynthetic electron transport. However, the critical signal for the regulatory mechanism of DNA replication has not been identified. In addition, conservation of this regulatory mechanism has not been investigated among cyanobacteria. To understand this regulatory signal and its dependence on light, we examined the regulation of DNA replication under both light and dark conditions among three model cyanobacteria, S. elongatus PCC 7942, Synechocystis sp. PCC 6803 and Anabaena sp. PCC 7120. Interestingly, DNA replication activity in Synechocystis and Anabaena was retained when cells were transferred to the dark, although it was drastically decreased in S. elongatus. Glycogen metabolism and respiration were higher in Synechocystis and Anabaena than in S. elongatus in the dark. Moreover, DNA replication activity in Synechocystis and Anabaena was reduced to the same level as that in S. elongatus by inhibition of respiratory electron transport after transfer to the dark. These results demonstrate that there is disparity in DNA replication occurring in the dark among cyanobacteria, which is caused by the difference in activity of respiratory electron transport.


Asunto(s)
Cianobacterias/metabolismo , Cianobacterias/genética , Replicación del ADN/genética , Replicación del ADN/fisiología , Transporte de Electrón/genética , Transporte de Electrón/fisiología , Luz , Fotosíntesis/genética , Fotosíntesis/fisiología
18.
Environ Technol ; 37(4): 466-471, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26495932

RESUMEN

Effects of temperature, light, coexistent microbes, and dissolved matter on the growth of cyanobacteria Aphanothece clathrata and Microcystis wesenbergii were discussed using a batch incubation system in this research for microbial biomass production in wastewater. As a result, water temperature in the effluents from the municipal wastewater treatment plants in Tokyo was suitable for the growth of these cyanobacteria, though preheating of wastewater may be required for M. wesenbergii in winter. The dissolved matter in the treated wastewater did not affect the growth of A. clathrata and enhanced the growth of M. wesenbergii. However, the microbes in the treated wastewater attacked the cyanobacteria and inhibited their growth. Therefore, pretreatment of microbes might be required for biomass production in the treated wastewater. The maximum methane production potentials of A. clathrata and M. wesenbergii in the treated wastewater were estimated to be 13.5 and 2.12 L-CH4•m-2•day-1, respectively, when the depth of the bioreactor was set at 4.8 m for A. clathrata and 0.7 m for M. wesenbergii. The potential of A. clathrata was higher than that of grasses. Consequently, cyanobacteria, especially A. clathrata, may become a good biomass for bioenergy production.

19.
Chem Sci ; 7(6): 3791-3797, 2016 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-30155021

RESUMEN

Catalytic discrimination between inequivalent formyl groups was achieved using an aniline-type acid-base catalyst for the regio-, diastereo-, and enantioselective intramolecular cross-aldol reactions of enolizable dials. Although l-proline gave a mixture of the regio- and stereoisomeric products in the presence of an N-containing 1,6-dial, the aniline-type catalyst afforded anti-3,4-disubstituted pyrrolidine in high regio-, and stereoselectivity beyond the background reaction, which led to the regioisomeric 2,3-disubstituted products. The mild reactivity of the aniline-type amine facilitated catalytic discrimination between the inequivalent formyl groups. Kinetic isotope effect studies and reductive amination experiments suggested that the regioselectivity was controlled under the enamine-forming steps.

20.
FEBS Open Bio ; 5: 357-68, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25973363

RESUMEN

Dietary or caloric restriction confers various clinical benefits. Short-term fasting of mice is a common experimental procedure that may involve systemic metabolic remodeling, which may significantly affect experimental outputs. This study evaluated adaptive cellular responses after 1- or 2-day fasting in 13 mouse tissues by quantitative PCR using 15 marker primer sets for the activation of ubiquitin-proteasome (Atrogin-1 and MuRF1), autophagy-lysosome (LC3b, p62 and Lamp2), amino acid response (Asns, Trib3, Herpud1, xCT, and Chop), Nrf2-mediated antioxidant (HO-1 and Gsta1), and amino acid transport (Slc38a2, Slc7a5, and Slc7a1) systems. Differential activation profiles obtained in seven highly (thymus, liver, spleen, and small intestine) or mildly (stomach, kidney, and colon) atrophied tissues as well as in six non-atrophied tissues (brain, eye, lung, heart, skeletal muscle, and testis) suggested tissue-specific active metabolic remodeling.

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