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1.
New Phytol ; 242(5): 1996-2010, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38571393

RESUMO

The conquest of land by plants was concomitant with, and possibly enabled by, the evolution of three-dimensional (3D) growth. The moss Physcomitrium patens provides a model system for elucidating molecular mechanisms in the initiation of 3D growth. Here, we investigate whether the phytohormone ethylene, which is believed to have been a signal before land plant emergence, plays a role in 3D growth regulation in P. patens. We report ethylene controls 3D gametophore formation, based on results from exogenously applied ethylene and genetic manipulation of PpEIN2, which is a central component in the ethylene signaling pathway. Overexpression (OE) of PpEIN2 activates ethylene responses and leads to earlier formation of gametophores with fewer gametophores produced thereafter, phenocopying ethylene-treated wild-type. Conversely, Ppein2 knockout mutants, which are ethylene insensitive, show initially delayed gametophore formation with more gametophores produced later. Furthermore, pharmacological and biochemical analyses reveal auxin levels are decreased in the OE lines but increased in the knockout mutants. Our results suggest that evolutionarily, ethylene and auxin molecular networks were recruited to build the plant body plan in ancestral land plants. This might have played a role in enabling ancient plants to acclimate to the continental surfaces of the planet.


Assuntos
Bryopsida , Etilenos , Regulação da Expressão Gênica de Plantas , Ácidos Indolacéticos , Proteínas de Plantas , Etilenos/metabolismo , Ácidos Indolacéticos/metabolismo , Ácidos Indolacéticos/farmacologia , Bryopsida/crescimento & desenvolvimento , Bryopsida/genética , Bryopsida/efeitos dos fármacos , Bryopsida/metabolismo , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Células Germinativas Vegetais/metabolismo , Células Germinativas Vegetais/crescimento & desenvolvimento , Células Germinativas Vegetais/efeitos dos fármacos , Mutação/genética
2.
Chemistry ; 30(27): e202400719, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38462510

RESUMO

A visible-light-induced strategy has been explored for the synthesis of naphtho[2,1-d]thiazol-2-amines through ortho-C-H sulfuration of 2-isocyanonaphthalenes with elemental sulfur and amines under external photocatalyst-free conditions. This three-component reaction, which utilizes elemental sulfur as the odorless sulfur source, molecular oxygen as the clean oxidant, and visible light as the clean energy source, provides a mild and efficient approach to construct a series of naphtho[2,1-d]thiazol-2-amines. Preliminary mechanistic studies indicated that visible-light-promoted photoexcitation of reaction intermediates consisting of thioureas and DBU might be involved in this transformation.

3.
Adv Mater ; 35(42): e2303632, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37435992

RESUMO

With the development of various gel-based flexible sensors, novel gels with multiple integrated and efficient properties, particularly recyclability, have been developed. Herein, a starch-based ADM (amylopectin (AP)-poly(3-[dimethyl-[2-(2-methylprop-2- enoyloxy)ethyl]azaniumyl]propane-1-sulfonate) (PDMAPS)-MXene) gel is prepared by a facile "cooking" strategy accompanying the gelatinization of AP and polymerization reaction of zwitterionic monomers. Reversible crosslinking in the gel occurs through hydrogen bonding and electrostatic interactions. The ADM gel exhibits high stretchability (≈2700%, after one month), swift self-healing performance, self-adhesive properties, favorable freezing resistance, and satisfactory moisturizing properties (≥30 days). Interestingly, the ADM gel can be recycled and reused by a "kneading" method and "dissolution-dialysis" process, respectively. Furthermore, the ADM gel can be assembled as a strain sensor with a broad working strain range (≈800%) and quick response time (response time 211 ms and recovery time 253 ms, under 10% strain) to detect various macro- and micro-human-motions, even under harsh conditions such as pronunciation and handwriting. The ADM gel can also be used as a humidity sensor to investigate humidity and human respiratory status, suggesting its practical application in personal health management. This study provides a novel strategy for the preparation of high-performance recycled gels and flexible sensors.

4.
Medicine (Baltimore) ; 102(25): e34142, 2023 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-37352025

RESUMO

RATIONALE: Multiple sclerosis (MS) is a central nervous system disease mainly mediated by immunity, which is one of the most common causes of neurological dysfunction in young people worldwide. In the acute phase, high-dose steroid therapy is effective. There are few reports about cerebral venous thrombosis (CVT) after high-dose steroid therapy. PATIENT CONCERNS: We present a case of a 19-year-old female diagnosed with MS who developed a headache after high-dose steroid therapy was diagnosed with CVT. Headache symptoms improved after anticoagulant treatment. DIAGNOSES: MS comorbid CVT. INTERVENTIONS: Anticoagulant therapy was added and hormone therapy was reduced. OUTCOMES: Clinical symptoms such as headache, limb numbness, and involuntary tremors in the right hand were improved, and the muscle strength of the right limb recovered to grade 4. The patient did not suffer from headaches after discharge and no abnormality in the computed tomography (CT) scan of the cephalic vein at the 5-months follow-up. LESSONS: High-dose steroid therapy may be a risk factor for CVT in patients with MS. MS patients who develop headaches during high-dose steroid therapy should undergo further cranial CTV to rule out CVT.


Assuntos
Trombose Intracraniana , Esclerose Múltipla , Trombose Venosa , Feminino , Humanos , Adolescente , Adulto Jovem , Adulto , Esclerose Múltipla/complicações , Esclerose Múltipla/tratamento farmacológico , Trombose Venosa/induzido quimicamente , Trombose Venosa/tratamento farmacológico , Trombose Venosa/diagnóstico , Trombose Intracraniana/induzido quimicamente , Trombose Intracraniana/diagnóstico por imagem , Trombose Intracraniana/tratamento farmacológico , Cefaleia/etiologia , Esteroides/uso terapêutico , Anticoagulantes/efeitos adversos
5.
J Chem Neuroanat ; 131: 102289, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37196826

RESUMO

BACKGROUND AND OBJECTIVE: Epilepsy is a common chronic brain disease. Despite the availability of various anti-seizure drugs, approximately 30 % of patients do not respond to treatment. Recent research suggests that Kalirin plays a role in regulating neurological function. However, the pathogenesis of Kalirin in epileptic seizures remains unclear. This study aims to investigate the role and mechanism of Kalirin in epileptogenesis. MATERIALS AND METHODS: An epileptic model was induced by intraperitoneal injection of pentylenetetrazole (PTZ). Endogenous Kalirin was inhibited using shRNA. The expression of Kalirin, Rac1, and Cdc42 in the hippocampal CA1 region was measured using Western blotting. Spine and synaptic structures were examined using Golgi staining and electron microscopy. Moreover, the necrotic neurons in CA1 were examined using HE staining. RESULTS: The results indicated that the epileptic score increased in epileptic animals, while inhibition of Kalirin decreased the epileptic scores and increased the latent period of the first seizure attack. Inhibition of Kalirin attenuated the increases in Rac1 expression, dendritic spine density, and synaptic vesicle number in the CA1 region induced by PTZ. However, the increase in Cdc42 expression was not affected by the inhibition of Kalirin. CONCLUSION: This study suggests that Kalirin is involved in the development of seizures by modulating the activity of Rac1, providing a novel anti-epileptic target.


Assuntos
Epilepsia , Fatores de Troca do Nucleotídeo Guanina , Proteínas Serina-Treonina Quinases , Transdução de Sinais , Proteínas rac1 de Ligação ao GTP , Animais , Região CA1 Hipocampal/metabolismo , Epilepsia/metabolismo , Neurônios/metabolismo , Pentilenotetrazol/metabolismo , Proteínas rac1 de Ligação ao GTP/metabolismo , Transdução de Sinais/fisiologia , Proteínas Serina-Treonina Quinases/metabolismo , Fatores de Troca do Nucleotídeo Guanina/metabolismo
6.
Carbohydr Polym ; 307: 120600, 2023 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-36781283

RESUMO

Starch with active hydroxyl groups is one of the most attractive carbohydrates for the preparation of gels in recent years. However, the mechanical properties, self-healing properties, self-adhesion properties, especially low-temperature resistance are generally unsatisfactory for current starch-based gels. Based on that, a multiple network structure of amylopectin-carboxymethyl cellulose-polyacrylamide (ACP) gel was prepared by a "cooking" method. Tannic acid (TA) was used to construct multiple hydrogen bonds among molecular chains. ACP gel demonstrates high elongation at break (1090 %) and strength, self-healing performance and adhesion behavior, extraordinary low-temperature resistance (-80 °C) and self-extinguishing. As a sensor device, ACP gel can effectively monitor human movements and microscopic expression changes and achieve real-time monitoring under harsh conditions (After multiple cutting-healing steps, under low-temperature conditions, even a month later). Additionally, ACP gel could be served to detect temperature changes with a wide operating range and a high sensitivity of 33 %·°C-1, which is promising to monitor the changes in temperature. More interestingly, ACP gel can even monitor the cooking process and breathing frequency with fast response, implying applications in food processing, disease diagnosis and medical treatment. This study provides new opportunities for the design and fabrication of carbohydrate-based gels with multiple performance and multifunctional electronic devices.


Assuntos
Adesivos , Amido , Humanos , Cimentos de Resina , Temperatura , Hidrogéis/química
7.
PLoS One ; 10(3): e0119510, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25785585

RESUMO

To identify optimal cut-off points of fasting plasma glucose (FPG) for two-step strategy in screening abnormal glucose metabolism and estimating prevalence in general Chinese population. A population-based cross-sectional study was conducted on 7913 people aged 20 to 74 years in Harbin. Diabetes and pre-diabetes were determined by fasting and 2 hour post-load glucose from the oral glucose tolerance test in all participants. Screening potential of FPG, cost per case identified by two-step strategy, and optimal FPG cut-off points were described. The prevalence of diabetes was 12.7%, of which 65.2% was undiagnosed. Twelve percent or 9.0% of participants were diagnosed with pre-diabetes using 2003 ADA criteria or 1999 WHO criteria, respectively. The optimal FPG cut-off points for two-step strategy were 5.6 mmol/l for previously undiagnosed diabetes (area under the receiver-operating characteristic curve of FPG 0.93; sensitivity 82.0%; cost per case identified by two-step strategy ¥261), 5.3 mmol/l for both diabetes and pre-diabetes or pre-diabetes alone using 2003 ADA criteria (0.89 or 0.85; 72.4% or 62.9%; ¥110 or ¥258), 5.0 mmol/l for pre-diabetes using 1999 WHO criteria (0.78; 66.8%; ¥399), and 4.9 mmol/l for IGT alone (0.74; 62.2%; ¥502). Using the two-step strategy, the underestimates of prevalence reduced to nearly 38% for pre-diabetes or 18.7% for undiagnosed diabetes, respectively. Approximately a quarter of the general population in Harbin was in hyperglycemic condition. Using optimal FPG cut-off points for two-step strategy in Chinese population may be more effective and less costly for reducing the missed diagnosis of hyperglycemic condition.


Assuntos
Glicemia/metabolismo , Diabetes Mellitus/diagnóstico , Teste de Tolerância a Glucose/estatística & dados numéricos , Hiperglicemia/diagnóstico , Estado Pré-Diabético/diagnóstico , Adulto , Idoso , Biomarcadores/sangue , China/epidemiologia , Estudos Transversais , Diabetes Mellitus/sangue , Diabetes Mellitus/epidemiologia , Diabetes Mellitus/prevenção & controle , Jejum , Feminino , Intolerância à Glucose , Teste de Tolerância a Glucose/economia , Humanos , Hiperglicemia/sangue , Hiperglicemia/epidemiologia , Hiperglicemia/prevenção & controle , Masculino , Programas de Rastreamento/economia , Programas de Rastreamento/estatística & dados numéricos , Pessoa de Meia-Idade , Estado Pré-Diabético/sangue , Estado Pré-Diabético/epidemiologia , Estado Pré-Diabético/prevenção & controle , Prevalência , Sensibilidade e Especificidade
8.
Zhonghua Yu Fang Yi Xue Za Zhi ; 38(4): 234-6, 2004 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-15312580

RESUMO

OBJECTIVE: To explore the factors influencing insulin resistance in children with different nutritional status during pubertal development. METHODS: Three hundred children with simple obese aged 7 to 17 years, and 300 normal healthy children and 300 children with malnutrition, matched for age (+/- 3 months) and height (+/- 2 cm), were selected. Fasting serum levels of leptin, insulin, glucose, total cholesterol (TC), triglycerides (TG), low density lipoprotein-cholesterol (LDL-C) and high density lipoprotein-cholesterol (HDL-C) were measured for them. RESULTS: Levels of fasting serum insulin in obese children, except for boys at Tanner stage I and girls at Tanner stage II, were higher than those in normal and malnutrition children (P < 0.01). Average serum level of leptin in obese boys and girls at varied Tanner stages was higher than that in normal children, and higher in normal children than that in children with malnutrition (P<0.01). Serum level of TG in obese children [(1.53 +/- 0.13) mmol/L] was higher than that in normal ones [(1.12 +/- 0.10) mmol/L] and in children with malnutrition [(1.03 +/- 0.09) mmol/L]. There was no significant difference in levels of fasting blood glucose and other blood lipids between the three groups of children. Insulin sensitivity decreased with pubertal development and its index reversely correlated with Tanner stage and serum level of leptin (r=-0.27 and -0.36, respectively, P<0.01). CONCLUSION: Obesity (BMI), serum level of leptin and pubertal development were independent risk factors for insulin resistance in children aged 7 to 17 years.


Assuntos
Resistência à Insulina , Insulina/sangue , Obesidade/sangue , Puberdade/fisiologia , Adolescente , Índice de Massa Corporal , Criança , Estradiol/sangue , Hormônio do Crescimento/metabolismo , Humanos , Leptina/sangue , Leptina/fisiologia , Masculino , Desnutrição/sangue , Obesidade/fisiopatologia , Testosterona/sangue
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