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1.
J Bacteriol ; : e0027624, 2024 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-39387572

RESUMO

NADPH is a redox cofactor that drives the anabolic reactions. Although major NADPH generation reactions have been identified in Escherichia coli, some minor reactions have not been identified. In the present study, we explored novel NADPH generation reactions by monitoring the fluorescence dynamics after the addition of carbon sources to starved cells, using a metagenome-derived blue fluorescent protein (mBFP) as an intracellular NADPH reporter. Perturbation analyses were performed on a glucose-6-phosphate isomerase (PGI) deletion strain and its parental strain. Interestingly, mBFP fluorescence increased not only in the parental strain but also in the ΔPGI strain after the addition of xylose. Because the ΔPGI strain cannot metabolize xylose through the oxidative pentose phosphate pathway, this suggests that an unexpected NADPH generation reaction contributes to an increase in fluorescence. To unravel this mystery, we deleted the NADPH generation enzymes including transhydrogenase, isocitrate dehydrogenase, NADP+-dependent malic enzyme, glucose-6-phosphate dehydrogenase (G6PDH), and 6-phosphogluconate dehydrogenase (6PGDH) in the ΔPGI strain, and revealed that G6PDH and 6PGDH contribute to an increase in fluorescence under xylose conditions. In vitro assays using purified enzymes showed that G6PDH can produce NADPH using erythrose-4-phosphate (E4P) as a substitute for glucose-6-phosphate. Because the Km (0.65 mM) for E4P was much higher than the reported intracellular E4P concentrations in E. coli, little E4P must be metabolized through this bypass in the parental strain. However, the flux would increase when E4P accumulates in the cells owing to genetic modifications. This finding provides a metabolic engineering strategy for generating NADPH to produce useful compounds using xylose as a carbon source.IMPORTANCEBecause NADPH is consumed during the synthesis of various useful compounds, enhancing NADPH regeneration is highly desirable in metabolic engineering. In this study, we explored novel NADPH generation reactions in Escherichia coli using a fluorescent NADPH reporter and found that glucose-6-phosphate dehydrogenase can produce NADPH using erythrose-4-phosphate as a substrate under xylose conditions. Xylose is an abundant sugar in nature and is an attractive carbon source for bioproduction. Therefore, this finding contributes to novel pathway engineering strategies using a xylose carbon source in E. coli to produce useful compounds that consume NADPH for their synthesis.

2.
Metab Eng ; 84: 180-190, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38969164

RESUMO

Glutathione is a tripeptide of excellent value in the pharmaceutical, food, and cosmetic industries that is currently produced during yeast fermentation. In this case, glutathione accumulates intracellularly, which hinders high production. Here, we engineered Escherichia coli for the efficient production of glutathione. A total of 4.3 g/L glutathione was produced by overexpressing gshA and gshB, which encode cysteine glutamate ligase and glutathione synthetase, respectively, and most of the glutathione was excreted into the culture medium. Further improvements were achieved by inhibiting degradation (Δggt and ΔpepT); deleting gor (Δgor), which encodes glutathione oxide reductase; attenuating glutathione uptake (ΔyliABCD); and enhancing cysteine production (PompF-cysE). The engineered strain KG06 produced 19.6 g/L glutathione after 48 h of fed-batch fermentation with continuous addition of ammonium sulfate as the sulfur source. We also found that continuous feeding of glycine had a crucial role for effective glutathione production. The results of metabolic flux and metabolomic analyses suggested that the conversion of O-acetylserine to cysteine is the rate-limiting step in glutathione production by KG06. The use of sodium thiosulfate largely overcame this limitation, increasing the glutathione titer to 22.0 g/L, which is, to our knowledge, the highest titer reported to date in the literature. This study is the first report of glutathione fermentation without adding cysteine in E. coli. Our findings provide a great potential of E. coli fermentation process for the industrial production of glutathione.


Assuntos
Escherichia coli , Glutationa , Engenharia Metabólica , Escherichia coli/genética , Escherichia coli/metabolismo , Glutationa/metabolismo , Glutationa/biossíntese , Glutationa/genética , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Glutationa Sintase/genética , Glutationa Sintase/metabolismo , Glutamato-Cisteína Ligase/genética , Glutamato-Cisteína Ligase/metabolismo , Fermentação
3.
J Neurol Sci ; 463: 123150, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-39067261

RESUMO

Brain biopsies are often considered for patients who cannot be diagnosed with various laboratory test results. However, physicians tend to be hesitant regarding their application in possibly non-neoplastic brain diseases, due to the invasiveness and risks. The aim was to determine the indications for brain biopsies in cases of neurological diseases of unknown etiology. We retrospectively evaluated diagnostic accuracy, laboratory findings (including a liquid biopsy for malignant lymphoma), magnetic resonance imaging (MRI) characteristics and the post-treatment outcomes of patients undergoing brain biopsies for neurological diseases of unknown etiology. The data of patients who had undergone a brain biopsy during their admission to Niigata University Hospital, between 2011 and 2024, were reviewed. Moreover, the laboratory data and MRI findings between patients with definitive and nonspecific biopsy diagnoses were compared. Twenty-six patients underwent a brain biopsy, and a definitive diagnosis was obtained in 14 patients (53.8%). Even in cases where a nonspecific diagnosis was made, biopsy findings helped rule out malignancy and guide clinical diagnosis and treatment decisions. The liquid biopsy for malignant lymphoma was performed in eight patients, with one yielding a positive result, consistent with primary central nervous system lymphoma. The sensitivity and specificity of liquid biopsy were 0.5 and 1, respectively. Diffusely contrasted cortical lesions and the presence of mass effects on MRI, were significantly associated with a definitive diagnosis, compared to a nonspecific diagnosis. In conclusion, brain MRI and liquid biopsies can assist in determining the appropriate indications for brain biopsies in neurological diseases of unknown etiology.


Assuntos
Encéfalo , Imageamento por Ressonância Magnética , Doenças do Sistema Nervoso , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Imageamento por Ressonância Magnética/métodos , Estudos Retrospectivos , Adulto , Encéfalo/patologia , Encéfalo/diagnóstico por imagem , Doenças do Sistema Nervoso/diagnóstico por imagem , Doenças do Sistema Nervoso/etiologia , Doenças do Sistema Nervoso/patologia , Biópsia , Biópsia Líquida/métodos , Idoso de 80 Anos ou mais , Encefalopatias/patologia , Encefalopatias/diagnóstico por imagem
4.
Neuron ; 112(15): 2540-2557.e8, 2024 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-38843838

RESUMO

Deposition of α-synuclein fibrils is implicated in Parkinson's disease (PD) and dementia with Lewy bodies (DLB), while in vivo detection of α-synuclein pathologies in these illnesses has been challenging. Here, we have developed a small-molecule ligand, C05-05, for visualizing α-synuclein deposits in the brains of living subjects. In vivo optical and positron emission tomography (PET) imaging of mouse and marmoset models demonstrated that C05-05 captured a dynamic propagation of fibrillogenesis along neural pathways, followed by disruptions of these structures. High-affinity binding of 18F-C05-05 to α-synuclein aggregates in human brain tissues was also proven by in vitro assays. Notably, PET-detectable 18F-C05-05 signals were intensified in the midbrains of PD and DLB patients as compared with healthy controls, providing the first demonstration of visualizing α-synuclein pathologies in these illnesses. Collectively, we propose a new imaging technology offering neuropathology-based translational assessments of PD and allied disorders toward diagnostic and therapeutic research and development.


Assuntos
Modelos Animais de Doenças , Doença por Corpos de Lewy , Doença de Parkinson , Tomografia por Emissão de Pósitrons , alfa-Sinucleína , Animais , alfa-Sinucleína/metabolismo , Doença de Parkinson/metabolismo , Doença de Parkinson/patologia , Doença de Parkinson/diagnóstico por imagem , Humanos , Camundongos , Tomografia por Emissão de Pósitrons/métodos , Doença por Corpos de Lewy/metabolismo , Doença por Corpos de Lewy/patologia , Doença por Corpos de Lewy/diagnóstico por imagem , Callithrix , Masculino , Encéfalo/metabolismo , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Feminino , Idoso , Camundongos Endogâmicos C57BL
5.
Ann Neurol ; 96(2): 247-261, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38771066

RESUMO

OBJECTIVE: Although astrocytic pathology is a pathological hallmark of progressive supranuclear palsy (PSP), its pathophysiological role remains unclear. This study aimed to assess astrocyte reactivity in vivo in patients with PSP. Furthermore, we investigated alterations in brain lactate levels and their relationship with astrocyte reactivity. METHODS: We included 30 patients with PSP-Richardson syndrome and 30 healthy controls; in patients, tau deposition was confirmed through 18F-florzolotau positron emission tomography. Myo-inositol, an astroglial marker, and lactate were quantified in the anterior cingulate cortex through magnetic resonance spectroscopy. We measured plasma biomarkers, including glial fibrillary acidic protein as another astrocytic marker. The anterior cingulate cortex was histologically assessed in postmortem samples of another 3 patients with PSP with comparable disease durations. RESULTS: The levels of myo-inositol and plasma glial fibrillary acidic protein were significantly higher in patients than those in healthy controls (p < 0.05); these increases were significantly associated with PSP rating scale and cognitive function scores (p < 0.05). The lactate level was high in patients, and correlated significantly with high myo-inositol levels. Histological analysis of the anterior cingulate cortex in patients revealed reactive astrocytes, despite mild tau deposition, and no marked synaptic loss. INTERPRETATION: We discovered high levels of astrocyte biomarkers in patients with PSP, suggesting astrocyte reactivity. The association between myo-inositol and lactate levels suggests a link between reactive astrocytes and brain energy metabolism changes. Our results indicate that astrocyte reactivity in the anterior cingulate cortex precedes pronounced tau pathology and neurodegenerative processes in that region, and affects brain function in PSP. ANN NEUROL 2024;96:247-261.


Assuntos
Astrócitos , Proteína Glial Fibrilar Ácida , Giro do Cíngulo , Inositol , Ácido Láctico , Paralisia Supranuclear Progressiva , Humanos , Paralisia Supranuclear Progressiva/metabolismo , Paralisia Supranuclear Progressiva/diagnóstico por imagem , Paralisia Supranuclear Progressiva/patologia , Astrócitos/metabolismo , Astrócitos/patologia , Masculino , Feminino , Idoso , Pessoa de Meia-Idade , Proteína Glial Fibrilar Ácida/metabolismo , Proteína Glial Fibrilar Ácida/sangue , Ácido Láctico/sangue , Ácido Láctico/metabolismo , Inositol/metabolismo , Giro do Cíngulo/metabolismo , Giro do Cíngulo/diagnóstico por imagem , Giro do Cíngulo/patologia , Biomarcadores/sangue , Proteínas tau/metabolismo , Tomografia por Emissão de Pósitrons
6.
BMC Ophthalmol ; 24(1): 227, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38811878

RESUMO

OBJECTIVE: To present six cases exhibiting transient anterior subcapsular vacuolar lens opacities following early postoperative Tanito microhook trabeculotomy (TMH) performed by the same surgeon. METHODS: Six patients who underwent lens-sparing TMH at Meizankai Shimizu Eye Clinic from November 2021 to May 2023, and developed anterior subcapsular vacuolar lens opacities postoperatively were reviewed. Detailed records of surgeries, follow-up findings were collected and reported. RESULTS: In all six cases, anterior vacuolar subcapsular lens opacities were observed on the day after surgery, gradually decreasing without affecting visual acuity or contrast sensitivity. In all cases, without any specific interventions, the opacities disappeared by 21 months postoperatively. CONCLUSION: Anterior subcapsular cataracts, characterized by a vacuolar appearance and transient existence, should be recognized as an early complication of ab interno glaucoma surgery, possibly linked to use of distributed ophthalmic viscosurgical devices and excessive anterior chamber irrigation leading to traumatic cataracts on the lens surface.


Assuntos
Catarata , Trabeculectomia , Acuidade Visual , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Glaucoma/cirurgia , Pressão Intraocular/fisiologia , Cápsula do Cristalino/cirurgia , Cápsula do Cristalino/patologia , Complicações Pós-Operatórias , Estudos Retrospectivos , Trabeculectomia/efeitos adversos , Vacúolos/patologia
7.
Acta Neuropathol ; 147(1): 76, 2024 04 24.
Artigo em Inglês | MEDLINE | ID: mdl-38658413

RESUMO

Neuromyelitis optica spectrum disorder (NMOSD) is an autoimmune disease of the CNS characterized by the production of disease-specific autoantibodies against aquaporin-4 (AQP4) water channels. Animal model studies suggest that anti-AQP4 antibodies cause a loss of AQP4-expressing astrocytes, primarily via complement-dependent cytotoxicity. Nonetheless, several aspects of the disease remain unclear, including: how anti-AQP4 antibodies cross the blood-brain barrier from the periphery to the CNS; how NMOSD expands into longitudinally extensive transverse myelitis or optic neuritis; how multiphasic courses occur; and how to prevent attacks without depleting circulating anti-AQP4 antibodies, especially when employing B-cell-depleting therapies. To address these knowledge gaps, we conducted a comprehensive 'stage-dependent' investigation of immune cell elements in situ in human NMOSD lesions, based on neuropathological techniques for autopsied/biopsied CNS materials. The present study provided three major findings. First, activated or netting neutrophils and melanoma cell adhesion molecule-positive (MCAM+) helper T (TH) 17/cytotoxic T (TC) 17 cells are prominent, and the numbers of these correlate with the size of NMOSD lesions in the initial or early-active stages. Second, forkhead box P3-positive (FOXP3+) regulatory T (Treg) cells are recruited to NMOSD lesions during the initial, early-active or late-active stages, suggesting rapid suppression of proinflammatory autoimmune events in the active stages of NMOSD. Third, compartmentalized resident memory immune cells, including CD103+ tissue-resident memory T (TRM) cells with long-lasting inflammatory potential, are detected under "standby" conditions in all stages. Furthermore, CD103+ TRM cells express high levels of granzyme B/perforin-1 in the initial or early-active stages of NMOSD in situ. We infer that stage-dependent compartmentalized immune traits orchestrate the pathology of anti-AQP4 antibody-guided NMOSD in situ. Our work further suggests that targeting activated/netting neutrophils, MCAM+ TH17/TC17 cells, and CD103+ TRM cells, as well as promoting the expansion of FOXP3+ Treg cells, may be effective in treating and preventing relapses of NMOSD.


Assuntos
Aquaporina 4 , Autoanticorpos , Neuromielite Óptica , Neutrófilos , Neuromielite Óptica/imunologia , Neuromielite Óptica/patologia , Aquaporina 4/imunologia , Humanos , Neutrófilos/imunologia , Neutrófilos/patologia , Feminino , Autoanticorpos/imunologia , Masculino , Pessoa de Meia-Idade , Memória Imunológica , Adulto , Idoso , Células Th17/imunologia , Células Th17/patologia
8.
Curr Opin Biotechnol ; 87: 103133, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38640846

RESUMO

Microbial fermentation employs two strategies: growth- and nongrowth-coupled productions. Stoichiometric metabolic models with flux balance analysis enable pathway engineering to couple target synthesis with growth, yielding numerous successful results. Growth-coupled engineering also contributes to improving bottleneck flux through subsequent adaptive evolution. However, because growth-coupled production inevitably shares resources between biomass and target syntheses, the cost-effective production of bulk chemicals mandates a nongrowth-coupled approach. In such processes, understanding how and when to transition the metabolic state from growth to production modes becomes crucial, as does maintaining cellular activity during the nongrowing state to achieve high productivity. In this paper, we review recent technologies for growth-coupled and nongrowth-coupled production, considering their advantages and disadvantages.


Assuntos
Fermentação , Engenharia Metabólica , Engenharia Metabólica/métodos , Biomassa
9.
Neuropathology ; 2024 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-38583489

RESUMO

An 84-year-old man presented with somnolence, dysphagia, and right hemiplegia, all occurring within a month, approximately one year after initial admission due to subacute, transient cognitive decline suggestive of acute disseminated encephalomyelitis involving the cerebral white matter. Serial magnetic resonance imaging (MRI) studies over that period revealed three high-intensity signal lesions on fluid-attenuated inversion recovery images, appearing in chronological order in the left upper and left lower medulla oblongata and left pontine base. Despite some clinical improvement following methylprednisolone pulse therapy, the patient died of respiratory failure. Autopsy revealed four fresh, well-defined lesions in the brainstem, three of which corresponded to the lesions detected radiologically. The remaining lesion was located in the dorsal medulla oblongata and involved the right solitary nucleus. This might have appeared at a later disease stage, eventually causing respiratory failure. Histologically, all four lesions showed loss of myelin, preservation of axons, and infiltration of lymphocytes, predominantly CD8-positive T cells, consistent with the histological features of autoimmune demyelinating diseases, particularly the confluent demyelination observed in the early and acute phases of multiple sclerosis (MS). In the cerebral white matter, autoimmune demyelination appeared superimposed on ischemic changes, consistent with the cerebrospinal fluid (CSF) and MRI findings on initial admission. No anti-AQP4 or MOG antibodies or those potentially causing autoimmune encephalitis/demyelination were detected in either the serum or CSF. Despite several similarities to MS, such as the relapsing-remitting disease course and lesion histology, the entire clinicopathological picture in the present patient, especially the advanced age at onset and development of brainstem lesions in close proximity within a short time frame, did not fit those of MS or other autoimmune diseases that are currently established. The present results suggest that exceptionally older individuals can be affected by an as yet unknown inflammatory demyelinating disease of the CNS.

10.
Brain Tumor Pathol ; 41(2): 85-91, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38597999

RESUMO

Surgical biopsy is the gold standard for diagnosing central nervous system (CNS) lymphomas. However, reliable liquid biopsy methods for diagnosing CNS lymphomas have quickly developed and have been implicated in clinical decision-making. In the current report, we introduce two patients for whom liquid biopsy was essential for diagnosing CNS lymphomas and discuss the rapidly growing applications of this technology.


Assuntos
Neoplasias do Sistema Nervoso Central , Idoso , Feminino , Humanos , Masculino , Neoplasias do Sistema Nervoso Central/diagnóstico , Neoplasias do Sistema Nervoso Central/patologia , Biópsia Líquida/métodos , Linfoma/diagnóstico , Linfoma/patologia
11.
J Neurooncol ; 166(2): 273-282, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38227143

RESUMO

PURPOSE: Liquid biopsy of cyst fluid in brain tumors has not been extensively studied to date. The present study was performed to see whether diagnostic genetic alterations found in brain tumor tissue DNA could also be detected in cell-free DNA (cfDNA) of cyst fluid in cystic brain tumors. METHODS: Cyst fluid was obtained from 22 patients undergoing surgery for a cystic brain tumor with confirmed genetic alterations in tumor DNA. Pathological diagnoses based on WHO 2021 classification and diagnostic alterations in the tumor DNA, such as IDH1 R132H and TERT promoter mutation for oligodendrogliomas, were detected by Sanger sequencing. The same alterations were analyzed by both droplet digital PCR (ddPCR) and Sanger sequencing in cyst fluid cfDNA. Additionally, multiplex ligation-dependent probe amplification (MLPA) assays were performed to assess 1p/19q status, presence of CDKN2A loss, PTEN loss and EGFR amplification, to assess whether differentiating between astrocytomas and oligodendrogliomas and grading is possible from cyst fluid cfDNA. RESULTS: Twenty-five genetic alterations were found in 22 tumor samples. All (100%) alterations were detected in cyst fluid cfDNA by ddPCR. Twenty of the 25 (80%) alterations were also detected by Sanger sequencing of cyst fluid cfDNA. Variant allele frequency (VAF) in cyst fluid cfDNA was comparable to that of tumor DNA (R = 0.62, Pearson's correlation). MLPA was feasible in 11 out of 17 (65%) diffuse gliomas, with close correlation of results between tumor DNA and cyst fluid cfDNA. CONCLUSION: Cell-free DNA obtained from cyst fluid in cystic brain tumors is a reliable alternative to tumor DNA when diagnosing brain tumors.


Assuntos
Neoplasias Encefálicas , Ácidos Nucleicos Livres , Oligodendroglioma , Humanos , Oligodendroglioma/diagnóstico , Oligodendroglioma/genética , Oligodendroglioma/patologia , Líquido Cístico , Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Mutação , Reação em Cadeia da Polimerase Multiplex , DNA
12.
J Biosci Bioeng ; 137(3): 187-194, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38281859

RESUMO

Overexpression of proteins by introducing a DNA vector is among the most important tools for the metabolic engineering of microorganisms such as Escherichia coli. Protein overexpression imposes a burden on metabolism because metabolic pathways must supply building blocks for protein and DNA synthesis. Different E. coli strains have distinct metabolic capacities. In this study, two proteins were overexpressed in four E. coli strains (MG1655(DE3), W3110(DE3), BL21star(DE3), and Rosetta(DE3)), and their effects on metabolic burden were investigated. Metabolomic analysis showed that E. coli strains overexpressing green fluorescent protein had decreased levels of several metabolites, with a positive correlation between the number of reduced metabolites and green fluorescent protein expression levels. Moreover, nucleic acid-related metabolites decreased, indicating a metabolic burden in the E. coli strains, and the growth rate and protein expression levels were improved by supplementation with the five nucleosides. In contrast, two strains overexpressing delta rhodopsin, a microbial membrane rhodopsin from Haloterrigena turkmenica, led to a metabolic burden and decrease in the amino acids Ala, Val, Leu, Ile, Thr, Phe, Asp, and Trp, which are the most frequent amino acids in the delta rhodopsin protein sequence. The metabolic burden caused by protein overexpression was influenced by the metabolic capacity of the host strains and the sequences of the overexpressed proteins. Detailed characterization of the effects of protein expression on the metabolic state of engineered cells using metabolomics will provide insights into improving the production of target compounds.


Assuntos
Escherichia coli , Rodopsina , Proteínas de Fluorescência Verde/genética , Escherichia coli/genética , Metaboloma , Aminoácidos , DNA
13.
Acta Neuropathol Commun ; 12(1): 14, 2024 01 22.
Artigo em Inglês | MEDLINE | ID: mdl-38254245

RESUMO

Neurocutaneous melanosis (NCM) is a rare congenital neurocutaneous syndrome characterized by congenital melanocytic nevus of skin and abnormal proliferation of leptomeningeal melanocytes. Early acquisition of post-zygotic somatic mutations has been postulated to underlie the pathogenesis of NCM. The pathogenesis of NCM remains to be fully elucidated, and treatment options have not been established. Here, we report for the first time, multiregional genomic analyses in a 3-year-old autopsied girl with leptomeningeal melanomatosis associated with NCM, in which a ventriculo-peritoneal (VP) shunt was inserted for the treatment of hydrocephalus. The patient expired six months after the onset due to respiratory failure caused by abdominal dissemination via VP shunt. We performed multiregional exome sequencing to identify genomic differences among brain and abdominal tumors, nevus, and normal tissues. A total of 87 somatic mutations were found in 71 genes, with a significantly large number of gene mutations found in the tumor site. The genetic alterations detected in the nevus were only few and not shared with other sites. Three mutations, namely GNAQ R183Q, S1PR3 G89S and NRAS G12V, considered pathogenic, were found, although S1PR3 mutations have not been previously reported in melanocytic tumors. GNAQ and S1PR3 mutations were shared in both tumor and normal sites. Moreover, the mutant allele frequencies of the two mutations were markedly higher in tumor sites than in normal sites, with copy-neutral loss-of-heterozygosity (CN-LOH) occurring in tumor. NRAS mutation was found only in the abdominal tumor and was thought to be responsible for malignant progression in the present case. Multiregional comprehensive genetic analysis may lead to discovering novel driver mutations associated with tumorigenesis and targeted therapy.


Assuntos
Melanose , Síndromes Neurocutâneas , Nevo , Neoplasias Cutâneas , Feminino , Humanos , Pré-Escolar , Síndromes Neurocutâneas/genética , Mutação de Sentido Incorreto , Neoplasias Cutâneas/genética , Proteínas de Membrana/genética , GTP Fosfo-Hidrolases/genética
14.
J Gen Appl Microbiol ; 69(4): 185-195, 2024 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-36935115

RESUMO

Although n-butanol (BuOH) is an ideal fuel because of its superior physical properties, it has toxicity to microbes. Previously, a Synechococcus elongatus PCC 7942 derivative strain that produces BuOH from CO2 was developed by introducing six heterologous genes (BUOH-SE strain). To identify the bottleneck in BuOH production, the effects of BuOH production and its toxicity on central metabolism and the photosystem were investigated. Parental (WT) and BUOH-SE strains were cultured under autotrophic conditions. Consistent with the results of a previous study, BuOH production was observed only in the BUOH-SE strain. Isotopically non-stationary 13C-metabolic flux analysis revealed that the CO2 fixation rate was much larger than the BuOH production rate in the BUOH-SE strain (1.70 vs 0.03 mmol gDCW-1 h-1), implying that the carbon flow for BuOH biosynthesis was less affected by the entire flux distribution. No large difference was observed in the flux of metabolism between the WT and BUOH-SE strains. Contrastingly, in the photosystem, the chlorophyll content and maximum O2 evolution rate per dry cell weight of the BUOH-SE strain were decreased to 81% and 43% of the WT strain, respectively. Target proteome analysis revealed that the amounts of some proteins related to antennae (ApcA, ApcD, ApcE, and CpcC), photosystem II (PsbB, PsbU, and Psb28-2), and cytochrome b6f complex (PetB and PetC) in photosystems decreased in the BUOH-SE strain. The activation of photosynthesis would be a novel approach for further enhancing BuOH production in S. elongatus PCC 7942.


Assuntos
1-Butanol , Proteoma , Proteoma/genética , Complexo Citocromos b6f , Dióxido de Carbono , Fotossíntese , Butanóis
15.
Biotechnol Bioeng ; 121(3): 1016-1025, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38116710

RESUMO

Optogenetics is an attractive synthetic biology tool for controlling the metabolic flux distribution. Here, we demonstrated optogenetic flux ratio control of glycolytic pathways consisting of the Embden-Meyerhof-Parnas (EMP), pentose phosphate (PP), and Entner-Doudoroff (ED) pathways by illuminating multicolor lights using blue light-responsive EL222 and green/red light-responsive CcaSR in Escherichia coli. EL222 forms a dimer and binds to a particular DNA sequence under blue light; therefore, target gene expression can be reduced or induced by inserting a recognition sequence into its promoter regions. First, a flux ratio between the PP and ED pathways was controlled by blue light using EL222. After blocking the EMP pathway, the EL222-recognition sequence was inserted between the -35 and -10 regions of gnd to repress the PP flux and was also inserted upstream of the -35 region of edd to induce ED flux. After adjusting light intensity, the PP:ED flux ratios were 60:39% and 29:70% under dark and blue light conditions, respectively. Finally, a CcaSR-based pgi expression system was implemented to control the flux ratio between the EMP and PP + ED pathways by illuminating green/red light. The EMP:PP:ED flux ratios were 80:9:11%, 14:35:51%, and 33:5:62% under green, red, and red and blue light, respectively.


Assuntos
Escherichia coli , Optogenética , Escherichia coli/genética , Escherichia coli/metabolismo , Via de Pentose Fosfato , Glicólise/genética
16.
J Neurosurg Case Lessons ; 6(16)2023 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-37870755

RESUMO

BACKGROUND: Germinomatous germ cell tumor is highly sensitive to chemoradiotherapy; patients are expected to survive for decades. Many radiation-induced malignant gliomas (RIMGs) occur >10 years after radiotherapy. Standard therapy for RIMGs has not been established because of the lesion's rarity, the patient's shorter survival period, and the risk of radiation necrosis by repeat radiation. OBSERVATIONS: Two patients, a 32-year-old man and a 50-year-old man, developed glioblastomas more than 20 years after radiation monotherapy for germinoma with or without mature teratoma. The first patient showed a tumor in the left frontotemporal region with disseminated lesions and died 2 months after partial resection of the tumor without responding to the chemotherapy with temozolomide and bevacizumab. Methylation classifier analysis classified the pathology as closest to diffuse pediatric-type high-grade glioma, Rtk1 subtype. The second patient showed a tumor mass in the brainstem and left cerebellar peduncle, which worsened progressively during chemotherapy with temozolomide and bevacizumab. The tumor transiently responded to stereotactic radiotherapy with the CyberKnife. However, the patient died of RIMG recurrence-related aspiration pneumonia 11 months after the biopsy. Methylation classifier analysis classified the pathology as closest to infratentorial pilocytic astrocytoma. LESSONS: Chemoradiotherapy may improve the survival of patients with RIMGs. Furthermore, molecular features may influence the clinical, locoregional, and pathological features of RIMG.

17.
Clin J Gastroenterol ; 16(6): 859-863, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37608145

RESUMO

A 75-year-old female with a history of Parkinson's disease treatment and hypertension presented at the emergency section with sudden onset of right abdominal pain. Contrast-enhanced computed tomography revealed beaded irregular stenosis and dilation of the superior mesenteric artery (SMA) and an aneurysm in the branch of the pancreaticoduodenal artery (PDA) that communicates with the common hepatic artery and SMA. Additionally, a hematoma had formed in the retroperitoneal space, and extravasation of contrast medium from the pancreaticoduodenal artery aneurysm (PDAA) into the hematoma was observed. The celiac artery (CA) was compressed by the median arcuate ligament; stenosis of the CA at its origin and dilation on the distal side were observed. Based on the imaging findings, it was diagnosed that PDAA was ruptured, SMA developed segmental arterial mediolysis (SAM), and CA developed median arcuate ligament syndrome (MALS). The ruptured PDAA was thought to be caused by SAM combined with MALS. Transcatheter arterial embolization (TAE) was performed for the ruptured PDAA. To the best of our knowledge, there have been no reports of TAE for a ruptured PDAA caused by SAM and MALS. After TAE, the PDAA did not re-rupture.


Assuntos
Aneurisma Roto , Embolização Terapêutica , Síndrome do Ligamento Arqueado Mediano , Feminino , Humanos , Idoso , Síndrome do Ligamento Arqueado Mediano/complicações , Constrição Patológica/terapia , Pâncreas/irrigação sanguínea , Duodeno/irrigação sanguínea , Aneurisma Roto/complicações , Aneurisma Roto/diagnóstico por imagem , Aneurisma Roto/terapia , Embolização Terapêutica/métodos , Artéria Celíaca/diagnóstico por imagem , Hematoma/complicações
19.
ACS Nano ; 17(6): 5561-5569, 2023 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-36820647

RESUMO

One-dimensional (1D) conducting materials are of great interest as potential building blocks for integrated nanocircuits. Ternary 1D transition-metal chalcogenides, consisting of M6X6 wires with intercalated A atoms (M = Mo or W; X = S, Se, or Te; A = alkali or rare metals, etc.), have attracted much attention due to their 1D metallic behavior, superconductivity, and mechanical flexibility. However, the conventional solid-state reaction usually produces micrometer-scale bulk crystals, limiting their potential use as nanoscale conductors. Here we demonstrate a versatile method to fabricate indium (In)-intercalated W6Te6 (In-W6Te6) bundles with a nanoscale thickness. We first prepared micrometer-long, crystalline bundles of van der Waals W6Te6 wires using chemical vapor deposition and intercalated In into the crystal via a vapor-phase reaction. Atomic-resolution electron microscopy revealed that In atoms were surrounded by three adjacent W6Te6 wires. First-principles calculations suggested that their wire-by-wire stacking can transform through postgrowth intercalation. Individual In-W6Te6 bundles exhibited metallic behavior, as theoretically predicted. We further identified the vibrational modes by combining polarized Raman spectroscopy and nonresonant Raman calculations.

20.
Intern Med ; 62(20): 2971-2975, 2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-36792186

RESUMO

Plexiform neurofibromas (PNs) occur in approximately 50% of patients with neurofibromatosis type 1 (NF1). PNs are rare in the abdominal cavity and especially rare in hepatobiliary lesions. A 31-year-old man with NF1 had a tumor extending along the celiac artery, superior mesenteric artery, and intrahepatic portal vein. We diagnosed him with diffuse PN based on liver tumor biopsy findings and the tumor form. Because the tumor had invaded along the intrahepatic portal vein, surgical resection was deemed difficult, and the patient was followed up with imaging studies. The patient remained asymptomatic without tumor growth.


Assuntos
Neoplasias Hepáticas , Neurofibroma Plexiforme , Neurofibromatose 1 , Masculino , Humanos , Adulto , Neurofibroma Plexiforme/complicações , Neurofibroma Plexiforme/diagnóstico por imagem , Neurofibroma Plexiforme/cirurgia , Neurofibromatose 1/complicações , Neurofibromatose 1/diagnóstico por imagem , Abdome , Neoplasias Hepáticas/diagnóstico por imagem
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