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1.
RSC Chem Biol ; 5(8): 729-737, 2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-39092438

RESUMO

Human relaxin-2 (H2 relaxin) is a peptide hormone of about 6 kDa, first identified as a reproductive hormone involved in vasoregulation during pregnancy. It has recently attracted strong interest because of its diverse functions, including anti-inflammatory, anti-fibrotic, and vasodilatory, and has been suggested as a potential peptide-based drug candidate for a variety of diseases. Mature H2 relaxin is constituted by the A- and B-chains stabilized by two interchain disulfide (SS) bridges and one intrachain SS linkage. In this study, seleno-relaxins, SeRlx-α and SeRlx-ß, which are [C11UA,C11UB] and [C10UA,C15UA] variants of H2 relaxin, respectively, were synthesized via a one-pot oxidative chain assembly (folding) from the component A- and B-chains. The substitution of SS bonds in a protein with their analogue, diselenide (SeSe) bonds, has been shown to alter the physical, chemical, and physiological properties of the protein. The surface SeSe bond (U11A-U11B) enhanced the yield of chain assembly while the internal SeSe bond (U10A-U15A) improved the reaction rate of the folding, indicating that these bridges play a major role in controlling the thermodynamics and kinetics, respectively, of the folding mechanism. Furthermore, SeRlx-α and SeRlx-ß effectively reduced the expression of a tissue fibrosis-related factor in human endometriotic stromal cells. Thus, the findings of this study indicate that the S-to-Se substitution strategy not only enhances the foldability of relaxin, but also provides new guidance for the development of novel relaxin formulations for endometriosis treatment.

2.
Arch Gerontol Geriatr ; 120: 105354, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38309105

RESUMO

BACKGROUND: The association between weight loss and subsequent functional decline is uncertain. The study aims to elucidate the association between weight loss over a year and subsequent functional decline requiring assistance in performing their activities of daily living in older individuals. METHODS: The study used data from the publicly funded Long-Term Care Insurance service in Japan, which provides coverage for long-term care services for individuals unable to perform activities of daily living due to physical or cognitive impairment. The study enrolled people born in or before 1949, who underwent health checkups in both 2014 and 2015. The participants were followed from 2015 to the worsening of functional decline requiring long-term care services, death, or February 28, 2019, whichever occurred first. The risk of subsequent functional decline in each weight loss category was estimated using a Cox regression model adjusted for age, sex, baseline body mass index, smoking, and Charlson comorbidity index. RESULTS: We identified 67,452 eligible individuals from the database. The median follow-up period was 1,284 days. The hazard ratios (95 % confidence interval) of functional decline for -1 %, -2 %, -3 %, -4 %, and ≤-5% weight change compared to 0 % weight change were 1.17 (1.03-1.32), 1.26 (1.11-1.43), 1.29 (1.12-1.49), 1.61 (1.39-1.87), and 1.79 (1.58-1.99), respectively. CONCLUSIONS AND IMPLICATIONS: Older people with weight loss of 1 % or more were at risk of functional decline. Close weight monitoring may serve as an easy and inexpensive means of identifying older individuals at risk of functional decline.


Assuntos
Atividades Cotidianas , Disfunção Cognitiva , População do Leste Asiático , Humanos , Idoso , Estudos de Coortes , Disfunção Cognitiva/epidemiologia , Redução de Peso , Japão/epidemiologia
3.
J Org Chem ; 89(6): 4128-4133, 2024 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-38407917

RESUMO

Histrionicotoxin (HTX) alkaloids, which are isolated from Colombian poison dart frogs, are analgesic neurotoxins that modulate nicotinic acetylcholine receptors (nAChRs) as antagonists. Perhydrohistrionicotoxin (pHTX) is the potent synthetic analogue of HTX and possesses a 1-azaspiro[5.5]undecane skeleton common to the HTX family. Here, we show for the first time the divergent nine-step synthesis of pHTX and its three stereoisomers from the known aldehyde through a one-step construction of the 1-azaspiro[5.5]undecane framework from a linear amino ynone substrate. Surprisingly, some pHTX diastereomers exhibited antagonistic activities on the chicken α4ß2-neuronal nAChRs that were more potent than pHTX.


Assuntos
Venenos de Anfíbios , Galinhas , Receptores Nicotínicos , Animais , Alcanos
4.
Medicine (Baltimore) ; 103(7): e36782, 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38363934

RESUMO

RATIONALE: Although patients with central disorders of hypersomnolence (CDH) exhibit characteristic symptoms of hypersomnia frequently, it takes 5 to 15 years from the onset for its diagnosis due to the lack of symptom recognition. Here, we present a case of idiopathic hypersomnia (IH), a CDH, wherein early diagnosis was aided by a video footage of a spontaneous sleep attack. PATIENT CONCERNS: A 21-year-old man lost consciousness while driving and experienced an accident. He had complained of excessive daytime sleepiness (EDS) over half a year. During his hospitalization for close monitoring of the loss of consciousness, an in-room surveillance camera captured a 14-minutes long spontaneous sleep attack, during which he experienced general muscle weakness and loss of consciousness without warnings or convulsions leading to a fall from the bed. There were no abnormalities in vital signs. DIAGNOSES: There was no significant cataplexy and less than 2 sleep-onset rapid eye movements (SOREM) in 2 sleep latency tests, with a mean sleep latency of 2.1 and 4.6 minutes. Other sleep deprivation syndromes were excluded from differential diagnosis and finally, a diagnosis of IH was confirmed according to the criteria of the Third Edition of the International Classification of Sleep Disorders. During the course of the disease, attention-deficit/hyperactive disorder (ADHD) and a gaming disorder also diagnosed. INTERVENTIONS: Pharmacological treatment with modafinil was administered for IH and methylphenidate for ADHD. Cognitive behavioral therapy was performed for the gaming disorder. OUTCOMES: The EDS improved, and sleep attacks were no longer observed. The disruption of daily life caused by the gaming disorder was also reduced. LESSONS: Video recordings of sleep attacks are beneficial for identifying the cause of loss of consciousness. Home video recordings may be helpful in the early diagnosis of IH.


Assuntos
Distúrbios do Sono por Sonolência Excessiva , Hipersonia Idiopática , Humanos , Masculino , Adulto Jovem , Distúrbios do Sono por Sonolência Excessiva/diagnóstico , Distúrbios do Sono por Sonolência Excessiva/etiologia , Distúrbios do Sono por Sonolência Excessiva/tratamento farmacológico , Hipersonia Idiopática/diagnóstico , Hipersonia Idiopática/tratamento farmacológico , Modafinila/uso terapêutico , Sono/fisiologia , Inconsciência
5.
J Clin Periodontol ; 51(4): 380-389, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38171535

RESUMO

AIM: This study aimed to elucidate the impact of periodontal therapy on glycaemic control in individuals with type 2 diabetes and various baseline blood glucose levels using a large-scale claims database from Japan. MATERIALS AND METHODS: Using the JMDC Claims Database, we identified individuals with type 2 diabetes who underwent health check-ups in the fiscal years 2018 or 2019 and were followed up until the next year's health check-up. We conducted a weighted cohort analysis using stabilized inverse probability weights for treatment and censoring to estimate the effect of periodontal therapy on changes in haemoglobin A1c levels within a year. Analysis was done for different baseline haemoglobin A1c categories: 6.5%-6.9%, 7.0%-7.9% and ≥8.0%. RESULTS: Of the 4279 insured persons included in the study, 957 received periodontal therapy. Overall, there was a tendency towards improved glycaemic control among those who received periodontal therapy. Participants with baseline haemoglobin A1c levels of 7.0%-7.9% who received periodontal therapy exhibited significantly better glycaemic control compared with those without dental visits (difference; -0.094 [95% confidence interval: -0.181 to -0.007]). CONCLUSIONS: Periodontal therapy may improve glycaemic control in individuals with diabetes, especially in those with haemoglobin A1c levels ≥7.0%.


Assuntos
Diabetes Mellitus Tipo 2 , Controle Glicêmico , Humanos , Diabetes Mellitus Tipo 2/terapia , Hemoglobinas Glicadas , Bases de Dados Factuais , Japão
8.
Nature ; 625(7993): 126-133, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38123680

RESUMO

Chemical signalling is the primary means by which cells communicate in the embryo. The underlying principle refers to a group of ligand-producing cells and a group of cells that respond to this signal because they express the appropriate receptors1,2. In the zebrafish embryo, Wnt5b binds to the receptor Ror2 to trigger the Wnt-planar cell polarity (PCP) signalling pathway to regulate tissue polarity and cell migration3,4. However, it remains unclear how this lipophilic ligand is transported from the source cells through the aqueous extracellular space to the target tissue. In this study, we provide evidence that Wnt5b, together with Ror2, is loaded on long protrusions called cytonemes. Our data further suggest that the active Wnt5b-Ror2 complexes form in the producing cell and are handed over from these cytonemes to the receiving cell. Then, the receiving cell has the capacity to initiate Wnt-PCP signalling, irrespective of its functional Ror2 receptor status. On the tissue level, we further show that cytoneme-dependent spreading of active Wnt5b-Ror2 affects convergence and extension in the zebrafish gastrula. We suggest that cytoneme-mediated transfer of ligand-receptor complexes is a vital mechanism for paracrine signalling. This may prompt a reevaluation of the conventional concept of characterizing responsive and non-responsive tissues solely on the basis of the expression of receptors.


Assuntos
Pseudópodes , Receptores Órfãos Semelhantes a Receptor Tirosina Quinase , Proteínas Wnt , Peixe-Zebra , Animais , Gástrula/citologia , Gástrula/embriologia , Gástrula/metabolismo , Ligantes , Proteínas Wnt/metabolismo , Via de Sinalização Wnt/fisiologia , Peixe-Zebra/embriologia , Peixe-Zebra/metabolismo , Polaridade Celular , Movimento Celular , Pseudópodes/metabolismo , Receptores Órfãos Semelhantes a Receptor Tirosina Quinase/metabolismo , Comunicação Parácrina
9.
Osteoporos Int ; 35(4): 733-736, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38102330

RESUMO

A 70-year-old female patient was admitted for close examination and treatment of hypercalcemia (corrected serum calcium levels: 3.04 mmol/L) and renal dysfunction (serum creatinine levels: 254.59 µmol/L). The patient had a history of sarcoidosis, diagnosed based on epithelioid cell granulomas in subcutaneous nodule biopsies, uveitis, and bilateral hilar lymphadenopathy, which had spontaneously remitted 10 years before admission. Because the patient was diagnosed with hypercalcemia associated with recurrent sarcoidosis, prednisone (20 mg/day) was initiated, and its dose was tapered following the decrease in serum calcium and creatinine levels. However, the levels of these parameters increased again when the prednisone dose was reduced to ≤ 4 mg/day. We were concerned about glucocorticoid-induced osteoporosis in the patient but hesitated to use first-line bisphosphonates because of renal dysfunction. Therefore, denosumab was initiated to reduce the risk of hypercalcemia, renal dysfunction, and glucocorticoid-induced osteoporosis. Serum creatinine and corrected serum calcium levels subsequently decreased. The prednisone dose could be reduced following repeated denosumab administration.Thus, denosumab can be a multifaceted, beneficial option for sarcoidosis-induced hypercalcemia, as it alleviates renal dysfunction indirectly by normalizing serum calcium levels, facilitates reduction of the glucocorticoid dose, and ameliorates glucocorticoid-induced osteoporosis.


Assuntos
Hipercalcemia , Nefropatias , Osteoporose , Sarcoidose , Idoso , Feminino , Humanos , Cálcio , Creatinina , Denosumab/uso terapêutico , Glucocorticoides/efeitos adversos , Granuloma/complicações , Hipercalcemia/induzido quimicamente , Hipercalcemia/tratamento farmacológico , Osteoporose/induzido quimicamente , Osteoporose/complicações , Osteoporose/tratamento farmacológico , Prednisona/efeitos adversos , Sarcoidose/complicações , Sarcoidose/tratamento farmacológico
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