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1.
Geriatr Gerontol Int ; 24(1): 161-167, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38062994

RESUMO

AIM: Whether sex differences exist in hereditary progeroid syndromes remains unclear. In this study, we investigated sex differences in patients with Werner syndrome (WS), a model of human aging, using patient data at the time of diagnosis. METHODS: The presence of six cardinal signs in the diagnostic criteria was retrospectively evaluated. RESULTS: We found that the percentage of patients with all cardinal signs was higher in males than in females (54.2% vs. 21.2%). By the age of 40 years, 57.1% of male patients with WS presented with all the cardinal signs, whereas none of the female patients developed all of them. In particular, the frequency of having a high-pitched, hoarse voice, a characteristic of WS, was lower in female patients. The positive and negative predictive values for clinical diagnosis were 100% for males and females, indicating the helpfulness of diagnostic criteria regardless of sex. More female patients than male (86.7% vs. 64%) required genetic testing for their diagnosis because their clinical symptoms were insufficient, suggesting the importance of genetic testing for females even if they do not show typical symptoms of WS. Finally, the frequency of abnormal voice was lower in patients with WS harboring the c.3139-1G > C homozygous mutation. CONCLUSION: These results indicate, for the first time, that there are sex differences in the phenotypes of hereditary progeroid syndromes. The analysis of this mechanism in this human model of aging may lead to the elucidation of sex differences in the various symptoms of normal human aging. Geriatr Gerontol Int 2024; 24: 161-167.


Assuntos
Síndrome de Werner , Humanos , Masculino , Feminino , Síndrome de Werner/diagnóstico , Síndrome de Werner/genética , Estudos Retrospectivos , Caracteres Sexuais , Helicase da Síndrome de Werner/genética , Mutação
2.
Aging (Albany NY) ; 15(19): 9948-9964, 2023 10 03.
Artigo em Inglês | MEDLINE | ID: mdl-37793000

RESUMO

Werner syndrome (WS) is a hereditary premature aging disorder characterized by visceral fat accumulation and subcutaneous lipoatrophy, resulting in severe insulin resistance. However, its underlying mechanism remains unclear. In this study, we show that senescence-associated inflammation and suppressed adipogenesis play a role in subcutaneous adipose tissue reduction and dysfunction in WS. Clinical data from four Japanese patients with WS revealed significant associations between the decrease of areas of subcutaneous fat and increased insulin resistance measured by the glucose clamp. Adipose-derived stem cells from the stromal vascular fraction derived from WS subcutaneous adipose tissues (WSVF) showed early replicative senescence and a significant increase in the expression of senescence-associated secretory phenotype (SASP) markers. Additionally, adipogenesis and insulin signaling were suppressed in WSVF, and the expression of adipogenesis suppressor genes and SASP-related genes was increased. Rapamycin, an inhibitor of the mammalian target of rapamycin (mTOR), alleviated premature cellular senescence, rescued the decrease in insulin signaling, and extended the lifespan of WS model of C. elegans. To the best of our knowledge, this study is the first to reveal the critical role of cellular senescence in subcutaneous lipoatrophy and severe insulin resistance in WS, highlighting the therapeutic potential of rapamycin for this disease.


Assuntos
Resistência à Insulina , Insulinas , Lipodistrofia , Síndrome de Werner , Animais , Humanos , Síndrome de Werner/genética , Adipogenia/genética , Caenorhabditis elegans , Senescência Celular/genética , Gordura Subcutânea/metabolismo , Inflamação , Sirolimo , Mamíferos
3.
Diagnostics (Basel) ; 13(17)2023 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-37685313

RESUMO

Regional anatomical structures of the brain are intimately connected to functions corresponding to specific regions and the temporospatial pattern of genetic expression and their functions from the fetal period to old age. Therefore, quantitative brain morphometry has often been employed in neuroscience investigations, while controlling for the scanner effect of the scanner is a critical issue for ensuring accuracy in brain morphometric studies of rare orphan diseases due to the lack of normal reference values available for multicenter studies. This study aimed to provide across-site normal reference values of global and regional brain volumes for each sex and age group in children and adolescents. We collected magnetic resonance imaging (MRI) examinations of 846 neurotypical participants aged 6.0-17.9 years (339 male and 507 female participants) from 5 institutions comprising healthy volunteers or neurotypical patients without neurological disorders, neuropsychological disorders, or epilepsy. Regional-based analysis using the CIVET 2.1.0. pipeline provided regional brain volumes, and the measurements were across-site combined using ComBat-GAM harmonization. The normal reference values of global and regional brain volumes and lateral indices in our study could be helpful for evaluating the characteristics of the brain morphology of each individual in a clinical setting and investigating the brain morphology of ultra-rare diseases.

4.
Chemistry ; 29(59): e202301969, 2023 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-37500585

RESUMO

We describe a π-topological transformation-based synthetic method for the preparation of a new type of near-infrared (NIR)-emissive rhodamine dye called Polymethine-embedded Rhodamine Fluorophore (PeR Fluor). In contrast to conventional NIR-emissive dyes that require tedious synthetic steps and/or a high cost, linear fully π-conjugated PeR Fluor can be regioselectively prepared in one step by mixing different nucleophiles with ABPXs, a family of rhodamines with a cross-conjugated structure. PeR Fluor exhibits bright NIR fluorescence emission and high photostability owing to the cooperative π-electron system of rhodamines and polymethine scaffolds. Large bathochromic shifts of the absorption and fluorescence emission maxima can be achieved by modifying the N-substituted group to obtain NIR-absorbing/emitting PeR Fluor. We also demonstrate the stimulus-responsive functionality of PeR Fluor through the addition of chemicals (acid/base), which shows switchable NIR and visible fluorescence response. Our π-topological transformation-based synthetic method is a promising approach to produce new functionalized rhodamine dyes.

6.
Brain Dev ; 45(1): 16-25, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36511273

RESUMO

OBJECTIVE: Guillain-Barré syndrome (GBS), Fisher syndrome (FS), and Bickerstaff brainstem encephalitis (BBE) are immune-mediated neuropathies presenting with symptoms such as weakness, ophthalmoplegia, ataxia, and consciousness disturbances. Although the epidemiology of GBS and BBE in patients of all ages has been reported, childhood data have not been well-investigated. We aimed to determine the clinical features, therapeutics, and prognoses of childhood GBS, FS, and BBE in Japan. METHODS: We sent questionnaires to 1068 pediatric neurologists in Japan from 2014 to 2016 to determine the number of children less than 15 years old with GBS, FS, or BBE and their age and sex. We subsequently performed a secondary survey to investigate the clinical features, laboratory data, treatment, and prognosis. RESULTS: Five-hundred thirty-eight pediatric neurology specialists (50.4%) responded to the first survey. The total number of children with GBS, FS, and BBE in Japan from 2014 to 2016 were 87, 10, and 6, respectively. GBS was classified as acute inflammatory demyelinating neuropathy (35.6%), acute motor axonal neuropathy (20.7%), or acute motor-sensory axonal neuropathy (10.3%), with a male-to-female ratio of 1.29:1.0 and a wide distribution of onset ages. The disease severities of GBS, FS, and BBE were variable, but all children could walk within one year. CONCLUSION: The prognoses of childhood GBS, FS, and BBE were generally favorable, as long as the patient was promptly treated with either intravenous immunoglobulin or plasma exchange.


Assuntos
Encefalite , Síndrome de Guillain-Barré , Síndrome de Miller Fisher , Oftalmoplegia , Criança , Humanos , Masculino , Feminino , Adolescente , Síndrome de Miller Fisher/diagnóstico , Síndrome de Miller Fisher/epidemiologia , Síndrome de Miller Fisher/terapia , Síndrome de Guillain-Barré/diagnóstico , Síndrome de Guillain-Barré/epidemiologia , Síndrome de Guillain-Barré/terapia , Tronco Encefálico , Encefalite/diagnóstico , Encefalite/epidemiologia , Encefalite/terapia
7.
Nat Commun ; 13(1): 6189, 2022 10 19.
Artigo em Inglês | MEDLINE | ID: mdl-36261428

RESUMO

Naturally occurring plant cellulose, our most abundant renewable resource, consists of fibers of long polymer chains that are tightly packed in parallel arrays in either of two crystal phases collectively referred to as cellulose I. During mercerization, a process that involves treatment with sodium hydroxide, cellulose goes through a conversion to another crystal form called cellulose II, within which every other chain has remarkably changed direction. We designed a neutron diffraction experiment with deuterium labelling in order to understand how this change of cellulose chain direction is possible. Here we show that during mercerization of bacterial cellulose, chains fold back on themselves in a zigzag pattern to form crystalline anti-parallel domains. This result provides a molecular level understanding of one of the most widely used industrial processes for improving cellulosic materials.


Assuntos
Celulose , Difração de Nêutrons , Celulose/química , Hidróxido de Sódio/química , Deutério
8.
J Nat Prod ; 85(8): 2122-2125, 2022 08 26.
Artigo em Inglês | MEDLINE | ID: mdl-35976728

RESUMO

Echinosulfonic acid D, a sponge metabolite whose structure was recently reassigned, was synthesized for the first time. The key step is the double indolization of dimethylbarbituric acid using the umpolung indole reagent, followed by a hydrolysis/decarboxylation/esterification sequence.


Assuntos
Alcaloides Indólicos , Ácidos Sulfônicos , Hidrólise , Indicadores e Reagentes
9.
ACS Sustain Chem Eng ; 10(26): 8314-8325, 2022 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-35847521

RESUMO

One main challenge to utilize cellulose-based fibers as the precursor for carbon fibers is their inherently low carbon yield. This study aims to evaluate the use of keratin in chicken feathers, a byproduct of the poultry industry generated in large quantities, as a natural charring agent to improve the yield of cellulose-derived carbon fibers. Keratin-cellulose composite fibers are prepared through direct dissolution of the pulp and feather keratin in the ionic liquid 1,5-diazabicyclo[4.3.0]non-5-enium acetate ([DBNH]OAc) and subsequent dry jet wet spinning (so-called Ioncell process). Thermogravimetric analysis reveals that there is an increase in the carbon yield by ∼53 wt % with 30 wt % keratin incorporation. This increase is comparable to the one observed for lignin-cellulose composite fibers, in which lignin acts as a carbon booster due to its higher carbon content. Keratin, however, reduces the mechanical properties of cellulose precursor fibers to a lesser extent than lignin. Keratin introduces nitrogen and induces the formation of pores in the precursor fibers and the resulting carbon fibers. Carbon materials derived from the keratin-cellulose composite fiber show potential for applications where nitrogen doping and pores or voids in the carbon are desirable, for example, for low-cost bio-based carbons for energy harvest or storage.

10.
Nutrients ; 14(9)2022 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-35565662

RESUMO

Lactobacillus gasseri CP2305 (CP2305) is a paraprobiotic that exhibits beneficial effects on the intestinal function and microbiota, and increases resistance to psychological stress. The stress response mechanism mainly involves the hypothalamic-pituitary-adrenal axis, which is influenced by the gut-brain axis. Furthermore, the gut-brain axis also communicates bidirectionally with the intestinal microbiota. Additionally, the hypothalamic-pituitary-adrenal and hypothalamic-pituitary-gonadal axes share a common route that affects both mental and health aspects in women. This double-blind, placebo-controlled, parallel-group clinical trial aimed to analyze the influence of the intake of CP2305 on mild symptoms associated with menopause. Eighty women aged 40-60 years ingested CP2305 or placebo tablets for six consecutive menstrual cycles. Assessment was based on the observation of climacteric symptoms with two validated questionnaires-the Simplified Menopausal Index (SMI) and the Greene Climacteric Scale (GCS). The results showed that CP2305 provided significant relief in the SMI total score, SMI vasomotor score, SMI psychological score, GCS total score, GCS somatic score, and GCS vasomotor score compared to the placebo. The percentage of women with symptom relief for the SMI total score was 75.0%, with 30 of 40 women in the CP2305 group, and 55.0%, with 22 of 40 women in the placebo group (p = 0.0594). These findings provide new insights into the function of paraprobiotic CP2305 in relieving mild climacteric symptoms in women.


Assuntos
Climatério , Lactobacillus gasseri , Feminino , Humanos , Sistema Hipotálamo-Hipofisário , Lactobacillus gasseri/fisiologia , Menopausa , Pessoa de Meia-Idade , Sistema Hipófise-Suprarrenal
11.
Front Neurosci ; 16: 885335, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35620663

RESUMO

Rett syndrome (RTT) is a severe progressive neurodevelopmental disorder characterized by various neurological symptoms. Almost all RTT cases are caused by mutations in the X-linked methyl-CpG-binding protein 2 (MeCP2) gene, and several mouse models have been established to understand the disease. However, the neuroanatomical abnormalities in each brain region of RTT mouse models have not been fully understood. Here, we investigated the global and local neuroanatomy of the Mecp2 gene-deleted RTT model (Mecp2-KO) mouse brain using T2-weighted 3D magnetic resonance imaging with different morphometry to clarify the brain structural abnormalities that are involved in the pathophysiology of RTT. We found a significant reduction in global and almost all local volumes in the brain of Mecp2-KO mice. In addition, a detailed comparative analysis identified specific volume reductions in several brain regions in the Mecp2-deficient brain. Our analysis also revealed that the Mecp2-deficient brain shows changes in hemispheric asymmetry in several brain regions. These findings suggest that MeCP2 affects not only the whole-brain volume but also the region-specific brain structure. Our study provides a framework for neuroanatomical studies of a mouse model of RTT.

12.
Chemistry ; 28(37): e202201113, 2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35438809

RESUMO

This work reports the novel reactivity of hemiaminal as a precursor for indole editing at the multi-site. The HFIP-promoted indole editing of indoline hemiaminals affords 2-arylindoles through a ring-switch sequence. The key to success of this transformation is to use a cyclic hemiaminal as an α-amino aldehyde surrogate under transient tautomeric control. This transformation features mild reaction conditions and good yields with broad functional group tolerance. The utility of this transformation is presented through the one-pot protocol and the synthesis of isocryptolepine.


Assuntos
Indóis
14.
Org Lett ; 24(11): 2131-2136, 2022 03 25.
Artigo em Inglês | MEDLINE | ID: mdl-35285651

RESUMO

In peptide synthesis, it is important to distinguish the terminal amino group and carry out the selective transformation of only the N-terminal protecting group. We describe herein a reaction for the chemo- and site-selective replacement of carbamates with various other carbamates only at the N-terminus of peptides. We demonstrate the scope of carbamates and peptides and the introduction of fluorine into a peptide. This strategy is applicable to the late stage of peptide synthesis.


Assuntos
Carbamatos , Peptídeos , Técnicas de Química Sintética
16.
Chem Commun (Camb) ; 57(98): 13381-13384, 2021 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-34821884

RESUMO

Use of 3-azidoindoles in organic synthesis remains a difficult task owing to their instabilities. Herein, we report a general and concise approach for tackling this problem by using 3-azidoindole surrogates. The surrogates are bench-stable, presumably due to the observed intramolecular O-Nß bonding. The resultant fleeting intermediates undergo capturing in situ to afford 3-substitued indoles through formal ipso-substitution of the azide group by nucleophiles. In these investigations, we found that the fleeting 3-azidoindoles show a C3-electrophilic character for the first time.

17.
Biomacromolecules ; 22(11): 4805-4813, 2021 11 08.
Artigo em Inglês | MEDLINE | ID: mdl-34672541

RESUMO

Prehydrolysis kraft (PHK) pulps account for more than half of the global market of dissolving pulp. Characterized by high reactivity toward dissolution, their performances can still be improved by activation treatments. This study compares the dissolution kinetics in cupriethylenediamine of a hardwood and a softwood PHK pulps before and after their activation by high-solid-content mechano-enzymatic treatments. Three enzyme combinations were tested: endoglucanase (E), xylanase and mannanase (XM), and endoglucanase, xylanase, and mannanase (EXM). Xylanase and mannanase reduced the hemicellulose content of only hardwood (by max. 2.4%). Mixing and carbohydrate depolymerization decreased the dissolution time of hardwood and softwood pulps by a maximum of 63 and 30% with E, 37 and 16% with XM, and 44 and 30% with EXM, respectively. The shortening of the dissolution time was partially hindered by hornification, which increased with hemicellulose degradation. Interestingly, XM accelerated the dissolution while preserving a high weight-average molecular mass.


Assuntos
Celulase , Celulose , Polissacarídeos , Solubilidade , Madeira
18.
Chem Commun (Camb) ; 57(61): 7493-7496, 2021 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-34212954

RESUMO

We introduce readily available ammonium hemiaminals as O-transfer reagents and commercially available acetonitriles as a primary amide enolate precursor. The combination serves as an amide enolate equivalent, thereby providing one-pot access to α-substituted indolylacetamides. A broad substrate scope and good functional group tolerance as well as gram-scale synthesis make this protocol highly attractive. Mechanistic experiments suggest that the cyano group is trapped by a hydroxy group of hemiaminals en route to the desired primary amides under metal-free conditions.

19.
Brain Dev ; 43(7): 798-803, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33962821

RESUMO

BACKGROUND: Leukoencephalopathy with thalamus and brainstem involvement and high lactate (LTBL) is a hereditary disorder caused by biallelic variants in the EARS2 gene. Patients exhibit developmental delay, hypotonia, and hyperreflexia. Brain magnetic resonance imaging (MRI) reveals T2-hyperintensities in the deep white matter, thalamus, and brainstem, which generally stabilize over time. Herein, we report a case of LTBL, showing remitting and exacerbating white matter lesions. CASE DESCRIPTION: A non-consanguineous Japanese boy exhibited unsteady head control with prominent hypotonia, with no family history of neurological diseases. Brain MRI at one year of age revealed extensive T2-hyperintensities on the cerebral white matter, cerebellum, thalamus, basal ganglia, pons, and medulla oblongata. Magnetic resonance spectroscopy of the lesions showed lactate and myoinositol peaks. Whole-exome sequencing yielded novel compound heterozygous EARS2 variants of c.164G>T, p.Arg55Leu and c.484C>T, p.Arg162Trp. Interestingly, the lesions were reduced at three years of age, and new lesions emerged at eight years of age. At 10 years of age, the lesions were changed in the corpus callosum, deep cerebral white matter, and cerebellum, without physical exacerbation. The lesions improved one year later. CONCLUSION: We present the first case with remitting and exacerbating brain lesions in LTBL. EARS2 could relate to selective and specific brain regions and age dependency. Although the exact role of EARS2 remains unknown, the remitting and exacerbating imaging changes may be a clue in elucidating a novel EARS2 function in LTBL.


Assuntos
Tronco Encefálico , Progressão da Doença , Glutamato-tRNA Ligase/genética , Ácido Láctico/metabolismo , Leucoencefalopatias , Exacerbação dos Sintomas , Tálamo , Adolescente , Fatores Etários , Tronco Encefálico/diagnóstico por imagem , Tronco Encefálico/metabolismo , Tronco Encefálico/patologia , Humanos , Leucoencefalopatias/genética , Leucoencefalopatias/metabolismo , Leucoencefalopatias/patologia , Imageamento por Ressonância Magnética , Espectroscopia de Ressonância Magnética , Masculino , Remissão Espontânea , Tálamo/diagnóstico por imagem , Tálamo/metabolismo , Tálamo/patologia
20.
Brain Dev ; 43(2): 352-356, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33433331

RESUMO

BACKGROUND: Peripheral nerve imaging is increasingly recognized as a powerful tool to evaluate nerve hypertrophy in chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) and Charcot-Marie-Tooth diseases (CMT), whereas data in pediatric patients are limited. CASE DESCRIPTION: We describe the case of a 15-year-old Japanese girl with asymmetric demyelinating polyneuropathy, who, at the age of 10 years, was initially diagnosed with a demyelinating form of CMT. Fluorescence in situ hybridization for peripheral myelin 22 was negative, and already-known pathogenic variants were not detected by whole-genome sequencing, and nerve conduction studies revealed multifocal conduction blocks. Over the next 5 years, the patient showed gradual improvement in muscle weakness and sensory disturbance without immunological treatment and was referred to our hospital. RESULTS: At the age of 15 years, magnetic resonance (MR) neurography showed asymmetric multifocal fusiform enlargement of nerve roots, brachial and lumbosacral plexuses, and intermediated nerve trunks, as well as cranial nerves. Based on the MR neurography findings and multifocal nerve conduction blocks, she was diagnosed as having multifocal CIDP (multifocal demyelinating sensory and motor neuropathy [MADSAM]) according to the European Federation of Neurological Societies/Peripheral Nerve Society diagnostic criteria. DISCUSSION: Clinical diagnosis of childhood CIDP is challenging because its neurological manifestations and nerve conduction study findings occasionally resemble those of inherited demyelinating neuropathies. MR neurography is helpful for the assessment of patterns of nerve hypertrophy; MADSAM-CIDP is characterized by multiple fusiform nerve enlargement, whereas CMT shows symmetric and diffuse nerve hypertrophy. CONCLUSION: The MR neurography patterns would help in diagnosing pediatric demyelinating neuropathies.


Assuntos
Imageamento por Ressonância Magnética/métodos , Neuroimagem/métodos , Polirradiculoneuropatia Desmielinizante Inflamatória Crônica/diagnóstico por imagem , Adolescente , Feminino , Humanos , Polirradiculoneuropatia Desmielinizante Inflamatória Crônica/patologia
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