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1.
mBio ; 15(5): e0056224, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38564667

RESUMO

Spores of Bacillus subtilis germinate in response to specific germinant molecules that are recognized by receptors in the spore envelope. Germinants signal to the dormant spore that the environment can support vegetative growth, so many germinants, such as alanine and valine, are also essential metabolites. As such, they are also required to build the spore. Here we show that these germinants cause premature germination if they are still present at the latter stages of spore formation and beyond, but that B. subtilis metabolism is configured to prevent this: alanine and valine are catabolized and cleared from wild-type cultures even when alternative carbon and nitrogen sources are present. Alanine and valine accumulate in the spent media of mutants that are unable to catabolize these amino acids, and premature germination is pervasive. Premature germination does not occur if the germinant receptor that responds to alanine and valine is eliminated, or if wild-type strains that are able to catabolize and clear alanine and valine are also present in coculture. Our findings demonstrate that spore-forming bacteria must fine-tune the concentration of any metabolite that can also function as a germinant to a level that is high enough to allow for spore development to proceed, but not so high as to promote premature germination. These results indicate that germinant selection and metabolism are tightly linked, and suggest that germinant receptors evolve in tandem with the catabolic priorities of the spore-forming bacterium. IMPORTANCE: Many bacterial species produce dormant cells called endospores, which are not killed by antibiotics or common disinfection practices. Endospores pose critical challenges in the food industry, where endospore contaminations cause food spoilage, and in hospitals, where infections by pathogenic endospore formers threaten the life of millions every year. Endospores lose their resistance properties and can be killed easily when they germinate and exit dormancy. We have discovered that the enzymes that break down the amino acids alanine and valine are critical for the production of stable endospores. If these enzymes are absent, endospores germinate as they are formed or shortly thereafter in response to alanine, which can initiate the germination of many different species' endospores, or to valine. By blocking the activity of alanine dehydrogenase, the enzyme that breaks down alanine and is not present in mammals, it may be possible to inactivate endospores by triggering premature and unproductive germination.


Assuntos
Alanina , Aminoácidos , Bacillus subtilis , Esporos Bacterianos , Bacillus subtilis/metabolismo , Bacillus subtilis/genética , Bacillus subtilis/crescimento & desenvolvimento , Esporos Bacterianos/metabolismo , Esporos Bacterianos/crescimento & desenvolvimento , Esporos Bacterianos/genética , Alanina/metabolismo , Aminoácidos/metabolismo , Valina/metabolismo , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/genética , Meios de Cultura/química
2.
Artigo em Inglês | MEDLINE | ID: mdl-38591022

RESUMO

We characterize several stability properties, such as inverse or composition closedness, for ultraholomorphic function classes of Roumieu type defined in terms of a weight matrix. In this way we transfer and extend known results from J. Siddiqi and M. Ider, from the weight sequence setting and in sectors not wider than a half-plane, to the weight matrix framework and for sectors in the Riemann surface of the logarithm with arbitrary opening. The key argument rests on the construction, under suitable hypotheses, of characteristic functions in these classes for unrestricted sectors. As a by-product, we obtain new stability results when the growth control in these classes is expressed in terms of a weight sequence, or of a weight function in the sense of Braun-Meise-Taylor.

3.
Med Clin (Barc) ; 2024 Feb 20.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-38383268

RESUMO

BACKGROUND AND OBJECTIVES: Self-reported psychological variables related to pain have been posited as the major contributors to the quality of life of fibromyalgia (FM) women and should be considered when implementing therapeutic strategies among this population. The aim of this study was to explore the effect of low-pressure hyperbaric oxygen therapy (HBOT) on psychological constructs related to pain (i.e., pain catastrophism, pain acceptance, pain inflexibility, mental defeat) and quality of life in women with FM. METHODS: This was a randomized controlled trial. Thirty-three women with FM were randomly allocated to a low-pressure hyperbaric oxygen therapy group (HBOTG) (n=17), who received an 8-week intervention (5 sessions per week), and a control group (CG) (n=16). All women were assessed at baseline (T0) and upon completion of the study (T1) for self-perceived pain intensity, pain catastrophism, pain acceptance, pain inflexibility, mental defeat and quality of life. RESULTS: At T1, the HBOTG improved across all variables related to pain (i.e. self-perceived pain intensity, pain catastrophism, pain acceptance, pain flexibility, mental defeat) (p<0.05) and quality of life (p<0.05). In contrast, the CG showed no improvements in any variable. Furthermore, significant differences between the groups were found in quality of life (p<0.05) after the intervention. CONCLUSIONS: HBOT is effective at improving the psychological constructs related to pain (i.e. pain catastrophism, pain acceptance, pain flexibility, mental defeat) and quality of life among women with FM. Clinical Trial Link Clinical Trials gov identifier (NCT03801109).

4.
Results Math ; 78(3): 98, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36938127

RESUMO

We construct optimal flat functions in Carleman-Roumieu ultraholomorphic classes associated to general strongly nonquasianalytic weight sequences, and defined on sectors of suitably restricted opening. A general procedure is presented in order to obtain linear continuous extension operators, right inverses of the Borel map, for the case of regular weight sequences in the sense of Dyn'kin. Finally, we discuss some examples (including the well-known q-Gevrey case) where such optimal flat functions can be obtained in a more explicit way.

5.
Nat Commun ; 13(1): 5750, 2022 09 30.
Artigo em Inglês | MEDLINE | ID: mdl-36180430

RESUMO

Canonical RNA processing in mammalian mitochondria is defined by tRNAs acting as recognition sites for nucleases to release flanking transcripts. The relevant factors, their structures, and mechanism are well described, but not all mitochondrial transcripts are punctuated by tRNAs, and their mode of processing has remained unsolved. Using Drosophila and mouse models, we demonstrate that non-canonical processing results in the formation of 3' phosphates, and that phosphatase activity by the carbon catabolite repressor 4 domain-containing family member ANGEL2 is required for their hydrolysis. Furthermore, our data suggest that members of the FAST kinase domain-containing protein family are responsible for these 3' phosphates. Our results therefore propose a mechanism for non-canonical RNA processing in metazoan mitochondria, by identifying the role of ANGEL2.


Assuntos
Processamento Pós-Transcricional do RNA , RNA , Animais , Carbono/metabolismo , Drosophila , Exorribonucleases , Mamíferos/genética , Camundongos , Fosfatos/metabolismo , Monoéster Fosfórico Hidrolases/metabolismo , RNA/metabolismo , RNA Mitocondrial/genética , RNA Mitocondrial/metabolismo , RNA de Transferência/metabolismo
7.
J Nutr Metab ; 2022: 5232480, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36016842

RESUMO

Aim: To investigate the relation between malnutrition and nosocomial infections (NI) in hospitalized cancer patients. Methods: This observational, cross-sectional, noninterventional, descriptive study was conducted in a 500-bed university hospital in Valencia (Spain). Adult cancer patients admitted to the oncology ward were consecutively enrolled regardless of their nutritional status between November 2019 and March 2020. Patients were nutritionally assessed 24 to 48 hours after admission. Body weight, height and BMI, body composition through measurement of bioelectrical impedance analysis (BIA), and muscle strength and functionality using hand grip strength (HGS) were prospectively collected. The diagnosis of malnutrition and sarcopenia was assessed using the Global Leadership Initiative on Malnutrition (GLIM) criteria and the European Working Group on Sarcopenia in Older People (EWGSOP) criteria, respectively. Patients were followed up during their hospital stay or outpatient oncology visits to identify possible NI. Results: A total of 107 patients were included in this study (mean age 66 years; 66.4% were men). The most frequent reason for admission was cancer treatment (19.6%), followed by infections (18.7%) and digestive tract symptoms (18.7%). Overall, 77.5% (83/107) of the patients were malnourished at admission according to the GLIM criteria, while 52.3% (56/107) were sarcopenic. Nosocomial infections (NI) were significantly more frequent in malnourished (52.1%; 25/48) and severely malnourished (42.1%; 8/19) patients, compared with well-nourished patients without malnutrition (25%; 10/40; p=0.035). The mean length of hospital stay was 13.9 days, significantly longer in patients with an NI compared to those without infections (18.6 vs. 10.8 days, p < 0.024). Conclusion: This study evidenced the need to implement a routine protocol for the nutritional assessment and support of cancer patients at risk of malnutrition and sarcopenia to reduce the risk of NI during their hospital stay.

8.
Results Math ; 77(1): 28, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34924811

RESUMO

We characterize the equality between ultradifferentiable function classes defined in terms of abstractly given weight matrices and in terms of the corresponding matrix of associated weight functions by using new growth indices. These indices, defined by means of weight sequences and (associated) weight functions, are extending the notion of O-regular variation to a mixed setting. Hence we are extending the known comparison results concerning classes defined in terms of a single weight sequence and of a single weight function and give also these statements an interpretation expressed in O-regular variation.

9.
STAR Protoc ; 2(2): 100528, 2021 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-34027486

RESUMO

Here, we present a revised protocol to derive neuroepithelial stem (NES) cells from human induced pluripotent stem cells. NES cells can be further differentiated into a culture of neurons (90%) and glia (10%). We describe how to derive and maintain NES cells in culture and how to differentiate them. In addition, we show the potential use of NES cells to study the role of reactive oxygen species in neuronal differentiation and a guideline for NES cell transfection. For complete details on the use and execution of this protocol, please refer to Calvo-Garrido et al. (2019); Falk et al. (2012).


Assuntos
Técnicas de Cultura de Células/métodos , Diferenciação Celular/fisiologia , Células-Tronco Pluripotentes Induzidas/citologia , Células Neuroepiteliais/citologia , Células Cultivadas , Humanos , Neuroglia/citologia , Neurônios/citologia
10.
Elife ; 102021 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-34018921

RESUMO

The Gram-positive bacterium Bacillus subtilis can divide via two modes. During vegetative growth, the division septum is formed at the midcell to produce two equal daughter cells. However, during sporulation, the division septum is formed closer to one pole to yield a smaller forespore and a larger mother cell. Using cryo-electron tomography, genetics and fluorescence microscopy, we found that the organization of the division machinery is different in the two septa. While FtsAZ filaments, the major orchestrators of bacterial cell division, are present uniformly around the leading edge of the invaginating vegetative septa, they are only present on the mother cell side of the invaginating sporulation septa. We provide evidence suggesting that the different distribution and number of FtsAZ filaments impact septal thickness, causing vegetative septa to be thicker than sporulation septa already during constriction. Finally, we show that a sporulation-specific protein, SpoIIE, regulates asymmetric divisome localization and septal thickness during sporulation.


Assuntos
Bacillus subtilis/crescimento & desenvolvimento , Divisão Celular , Esporos Bacterianos/crescimento & desenvolvimento , Bacillus subtilis/genética , Bacillus subtilis/metabolismo , Bacillus subtilis/ultraestrutura , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Microscopia Crioeletrônica , Proteínas do Citoesqueleto/genética , Proteínas do Citoesqueleto/metabolismo , Citoesqueleto/genética , Citoesqueleto/metabolismo , Citoesqueleto/ultraestrutura , Tomografia com Microscopia Eletrônica , Regulação Bacteriana da Expressão Gênica , Microscopia de Fluorescência , Óperon , Transdução de Sinais , Esporos Bacterianos/genética , Esporos Bacterianos/metabolismo , Esporos Bacterianos/ultraestrutura , Fatores de Tempo
11.
Neurol Genet ; 7(2): e566, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33732874

RESUMO

OBJECTIVE: To investigate the pathogenicity of a novel MT-ND3 mutation identified in a patient with adult-onset sensorimotor axonal polyneuropathy and report the clinical, morphologic, and biochemical findings. METHODS: Clinical assessments and morphologic and biochemical investigations of skeletal muscle and cultured myoblasts from the patient were performed. Whole-genome sequencing (WGS) of DNA from skeletal muscle and Sanger sequencing of mitochondrial DNA (mtDNA) from both skeletal muscle and cultured myoblasts were performed. Heteroplasmic levels of mutated mtDNA in different tissues were quantified by last-cycle hot PCR. RESULTS: Muscle showed ragged red fibers, paracrystalline inclusions, a significant reduction in complex I (CI) respiratory chain (RC) activity, and decreased adenosine triphosphate (ATP) production for all substrates used by CI. Sanger sequencing of DNA from skeletal muscle detected a unique previously unreported heteroplasmic mutation in mtDNA encoded MT-ND3, coding for a subunit in CI. WGS confirmed the mtDNA mutation but did not detect any other mutation explaining the disease. Cultured myoblasts, however, did not carry the mutation, and RC activity measurements in myoblasts were normal. CONCLUSIONS: We report a case with adult-onset sensorimotor axonal polyneuropathy caused by a novel mtDNA mutation in MT-ND3. Loss of heteroplasmy in blood, cultured fibroblasts and myoblasts from the patient, and normal measurement of RC activity of the myoblasts support pathogenicity of the mutation. These findings highlight the importance of mitochondrial investigations in patients presenting with seemingly idiopathic polyneuropathy, especially if muscle also is affected.

12.
Mol Cell Proteomics ; 20: 100065, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33640490

RESUMO

Drosophila melanogaster has been a workhorse of genetics and cell biology for more than a century. However, proteomic-based methods have been limited due to the complexity and dynamic range of the fly proteome and the lack of efficient labeling methods. Here, we advanced a chemically defined food source into direct stable-isotope labeling of amino acids in flies (SILAF). It allows for the rapid and cost-efficient generation of a large number of larvae or flies, with full incorporation of lysine-[13C6] after six labeling days. SILAF followed by fractionation and enrichment gave proteomic insights at a depth of 7196 proteins and 8451 phosphorylation sites, which substantiated metabolic regulation on enzymatic level. We applied SILAF to quantify the mitochondrial phosphoproteome of an early-stage leucine-rich PPR motif-containing protein (LRPPRC)-knockdown fly model of mitochondrial disease that almost exclusively affects protein levels of the oxidative phosphorylation (OXPHOS) system. While the mitochondrial compartment was hypo-phosphorylated, two conserved phosphosites on OXPHOS subunits NDUFB10 and NDUFA4 were significantly upregulated upon impaired OXPHOS function. The ease and versatility of the method actuate the fruit fly as an appealing model in proteomic and posttranslational modification studies, and it enlarges potential metabolic applications based on heavy amino acid diets.


Assuntos
Proteínas de Drosophila/metabolismo , Proteínas Mitocondriais/metabolismo , Fosfoproteínas/metabolismo , Aminoácidos/metabolismo , Animais , Drosophila melanogaster , Feminino , Marcação por Isótopo , Masculino , Fosforilação , Proteoma
13.
Sci Adv ; 7(4)2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33523946

RESUMO

Despite intensive research, the role of metabolism in bacterial sporulation remains poorly understood. Here, we demonstrate that Bacillus subtilis sporulation entails a marked metabolic differentiation of the two cells comprising the sporangium: the forespore, which becomes the dormant spore, and the mother cell, which dies as sporulation completes. Our data provide evidence that metabolic precursor biosynthesis becomes restricted to the mother cell and that the forespore becomes reliant on mother cell-derived metabolites for protein synthesis. We further show that arginine is trafficked between the two cells and that proposed proteinaceous channels mediate small-molecule intercellular transport. Thus, sporulation entails the profound metabolic reprogramming of the forespore, which is depleted of key metabolic enzymes and must import metabolites from the mother cell. Together, our results provide a bacterial example analogous to progeny nurturing.


Assuntos
Proteínas de Bactérias , Esporos Bacterianos , Bacillus subtilis/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Transporte Biológico , Diferenciação Celular , Esporos Bacterianos/genética , Esporos Bacterianos/metabolismo
14.
Hum Mutat ; 42(4): 378-384, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33502047

RESUMO

Mutations in structural subunits and assembly factors of complex I of the oxidative phosphorylation system constitute the most common cause of mitochondrial respiratory chain defects. Such mutations can present a wide range of clinical manifestations, varying from mild deficiencies to severe, lethal disorders. We describe a patient presenting intrauterine growth restriction and anemia, which displayed postpartum hypertrophic cardiomyopathy, lactic acidosis, encephalopathy, and a severe complex I defect with fatal outcome. Whole genome sequencing revealed an intronic biallelic mutation in the NDUFB7 gene (c.113-10C>G) and splicing pattern alterations in NDUFB7 messenger RNA were confirmed by RNA Sequencing. The detected variant resulted in a significant reduction of the NDUFB7 protein and reduced complex I activity. Complementation studies with expression of wild-type NDUFB7 in patient fibroblasts normalized complex I function. Here we report a case with a primary complex I defect due to a homozygous mutation in an intron region of the NDUFB7 gene.


Assuntos
Acidose Láctica , Cardiomiopatia Hipertrófica , Doenças Mitocondriais , NADH NADPH Oxirredutases/genética , Acidose Láctica/genética , Cardiomiopatia Hipertrófica/genética , Complexo I de Transporte de Elétrons/genética , Humanos , Doenças Mitocondriais/genética , Mutação
15.
Mol Psychiatry ; 26(4): 1410-1423, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-31520067

RESUMO

Aggregation and accumulation of amyloid beta (Aß) are believed to play a key role in the pathogenesis of Alzheimer's disease (AD). We previously reported that Thioredoxin-80 (Trx80), a truncated form of Thioredoxin-1, prevents the toxic effects of Aß and inhibits its aggregation in vitro. Trx80 levels were found to be dramatically reduced both in the human brain and cerebrospinal fluid of AD patients. In this study, we investigated the effect of Trx80 expression using in vivo and in vitro models of Aß pathology. We developed Drosophila melanogaster models overexpressing either human Trx80, human Aß42, or both Aß42/Trx80 in the central nervous system. We found that Trx80 expression prevents Aß42 accumulation in the brain and rescues the reduction in life span and locomotor impairments seen in Aß42 expressing flies. Also, we show that Trx80 induces autophagosome formation and reverses the inhibition of Atg4b-Atg8a/b autophagosome formation pathway caused by Aß42. These effects were also confirmed in human neuroblastoma cells. These results give insight into Trx80 function in vivo, suggesting its role in the autophagosome biogenesis and thus in Aß42 degradation. Our findings put Trx80 on the spotlight as an endogenous agent against Aß42-induced toxicity in the brain suggesting that strategies to enhance Trx80 levels in neurons could potentially be beneficial against AD pathology in humans.


Assuntos
Doença de Alzheimer , Peptídeos beta-Amiloides , Doença de Alzheimer/genética , Animais , Drosophila melanogaster , Humanos , Lisossomos , Fragmentos de Peptídeos , Tiorredoxinas/genética
16.
J Geom Anal ; 30(4): 3458-3483, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33132667

RESUMO

We prove that, for asymptotically bounded holomorphic functions in a sector in C , an asymptotic expansion in a single direction towards the vertex with constraints in terms of a logarithmically convex sequence admitting a nonzero proximate order entails asymptotic expansion in the whole sector with control in terms of the same sequence. This generalizes a result by Fruchard and Zhang for Gevrey asymptotic expansions, and the proof strongly rests on a suitably refined version of the classical Phragmén-Lindelöf theorem, here obtained for functions whose growth in a sector is specified by a nonzero proximate order in the sense of Lindelöf and Valiron.

17.
Annu Rev Microbiol ; 74: 361-386, 2020 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-32660383

RESUMO

Endospore formation in Bacillus subtilis provides an ideal model system for studying development in bacteria. Sporulation studies have contributed a wealth of information about the mechanisms of cell-specific gene expression, chromosome dynamics, protein localization, and membrane remodeling, while helping to dispel the early view that bacteria lack internal organization and interesting cell biological phenomena. In this review, we focus on the architectural transformations that lead to a profound reorganization of the cellular landscape during sporulation, from two cells that lie side by side to the endospore, the unique cell within a cell structure that is a hallmark of sporulation in B. subtilis and other spore-forming Firmicutes. We discuss new insights into the mechanisms that drive morphogenesis, with special emphasis on polar septation, chromosome translocation, and the phagocytosis-like process of engulfment, and also the key experimental advances that have proven valuable in revealing the inner workings of bacterial cells.


Assuntos
Bacillus subtilis/genética , Bacillus subtilis/fisiologia , Esporos Bacterianos/crescimento & desenvolvimento , Bacillus subtilis/crescimento & desenvolvimento , Proteínas de Bactérias/metabolismo , Cromossomos Bacterianos/genética , Cromossomos Bacterianos/fisiologia , Ligação Proteica , Transporte Proteico , Esporos Bacterianos/genética
18.
Artigo em Inglês | MEDLINE | ID: mdl-32455853

RESUMO

Fibromyalgia (FM) is a chronic syndrome characterized by widespread pain and other physical and psychological features. In this study, we aimed to analyze the effect of a low-intensity physical exercise (PE) program, combining endurance training and coordination, on psychological aspects (i.e., pain catastrophizing, anxiety, depression, stress), pain perception (i.e., pain acceptance, pressure pain threshold (PPT), and quality of life and physical conditioning (i.e., self-perceived functional capacity, endurance and functional capacity, power and velocity) in women with FM. For this purpose, a randomized controlled trial was carried out. Thirty-two women with FM were randomly allocated to a PE group (PEG, n = 16), performing an eight-week low-intensity PE program and a control group (CG, n = 16). Pain catastrophizing, anxiety, depression, stress, pain acceptance, PPT, quality of life, self-perceived functional capacity, endurance and functional capacity, power, and velocity were assessed before and after the intervention. We observed a significant improvement in all studied variables in the PEG after the intervention (p < 0.05). In contrast, the CG showed no improvements in any variable, which further displayed poorer values for PPT (p < 0.05). In conclusion, a low-intensity combined PE program, including endurance training and coordination, improves psychological variables, pain perception, quality of life, and physical conditioning in women with FM.


Assuntos
Catastrofização , Terapia por Exercício/métodos , Exercício Físico , Fibromialgia/psicologia , Fibromialgia/terapia , Qualidade de Vida/psicologia , Treinamento Resistido/métodos , Ansiedade , Depressão , Exercício Físico/fisiologia , Exercício Físico/psicologia , Feminino , Fibromialgia/reabilitação , Humanos , Dor , Estresse Psicológico , Resultado do Tratamento
20.
Cell Mol Life Sci ; 77(13): 2483-2496, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31912194

RESUMO

Understanding the mechanisms behind neurodifferentiation in adults will be an important milestone in our quest to identify treatment strategies for cognitive disorders observed during our natural ageing or disease. It is now clear that the maturation of neural stem cells to neurones, fully integrated into neuronal circuits requires a complete remodelling of cellular metabolism, including switching the cellular energy source. Mitochondria are central for this transition and are increasingly seen as the regulatory hub in defining neural stem cell fate and neurodevelopment. This review explores our current knowledge of metabolism during adult neurodifferentiation.


Assuntos
Encéfalo/metabolismo , Células-Tronco Neurais/metabolismo , Neurogênese , Adulto , Animais , Humanos , Metabolismo dos Lipídeos , Mitocôndrias/ultraestrutura , Oxirredução , Espécies Reativas de Oxigênio/metabolismo
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