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1.
Nature ; 611(7936): 485-490, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36224388

RESUMO

Lithium-ion batteries with nickel-rich layered oxide cathodes and graphite anodes have reached specific energies of 250-300 Wh kg-1 (refs. 1,2), and it is now possible to build a 90 kWh electric vehicle (EV) pack with a 300-mile cruise range. Unfortunately, using such massive batteries to alleviate range anxiety is ineffective for mainstream EV adoption owing to the limited raw resource supply and prohibitively high cost. Ten-minute fast charging enables downsizing of EV batteries for both affordability and sustainability, without causing range anxiety. However, fast charging of energy-dense batteries (more than 250 Wh kg-1 or higher than 4 mAh cm-2) remains a great challenge3,4. Here we combine a material-agnostic approach based on asymmetric temperature modulation with a thermally stable dual-salt electrolyte to achieve charging of a 265 Wh kg-1 battery to 75% (or 70%) state of charge in 12 (or 11) minutes for more than 900 (or 2,000) cycles. This is equivalent to a half million mile range in which every charge is a fast charge. Further, we build a digital twin of such a battery pack to assess its cooling and safety and demonstrate that thermally modulated 4C charging only requires air convection. This offers a compact and intrinsically safe route to cell-to-pack development. The rapid thermal modulation method to yield highly active electrochemical interfaces only during fast charging has important potential to realize both stability and fast charging of next-generation materials, including anodes like silicon and lithium metal.

2.
Chemistry ; 28(27): e202200272, 2022 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-35286772

RESUMO

The development of convenient new methods for the synthesis of organic azides is highly desirable. Herein, we report a practical method for dehydroxyazidation of alcohols via an SN 2 pathway involving PPh3 and trifunctional benziodazolone-based hypervalent azido-iodine(III) reagents, which function as an electrophilic center, an azido source, and a base. This mild, chemoselective method was used for late-stage azidation of structurally complex alcohols, as well as for a new synthetic route to the antiepileptic drug rufinamide. The reaction mechanism was also investigated both experimentally and computationally.


Assuntos
Iodo , Álcoois , Azidas , Indicadores e Reagentes , Iodetos
3.
Nature ; 529(7587): 515-8, 2016 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-26789253

RESUMO

Lithium-ion batteries suffer severe power loss at temperatures below zero degrees Celsius, limiting their use in applications such as electric cars in cold climates and high-altitude drones. The practical consequences of such power loss are the need for larger, more expensive battery packs to perform engine cold cranking, slow charging in cold weather, restricted regenerative braking, and reduction of vehicle cruise range by as much as 40 per cent. Previous attempts to improve the low-temperature performance of lithium-ion batteries have focused on developing additives to improve the low-temperature behaviour of electrolytes, and on externally heating and insulating the cells. Here we report a lithium-ion battery structure, the 'all-climate battery' cell, that heats itself up from below zero degrees Celsius without requiring external heating devices or electrolyte additives. The self-heating mechanism creates an electrochemical interface that is favourable for high discharge/charge power. We show that the internal warm-up of such a cell to zero degrees Celsius occurs within 20 seconds at minus 20 degrees Celsius and within 30 seconds at minus 30 degrees Celsius, consuming only 3.8 per cent and 5.5 per cent of cell capacity, respectively. The self-heated all-climate battery cell yields a discharge/regeneration power of 1,061/1,425 watts per kilogram at a 50 per cent state of charge and at minus 30 degrees Celsius, delivering 6.4-12.3 times the power of state-of-the-art lithium-ion cells. We expect the all-climate battery to enable engine stop-start technology capable of saving 5-10 per cent of the fuel for 80 million new vehicles manufactured every year. Given that only a small fraction of the battery energy is used for self-heating, we envisage that the all-climate battery cell may also prove useful for plug-in electric vehicles, robotics and space exploration applications.

4.
Proc Natl Acad Sci U S A ; 115(28): 7266-7271, 2018 07 10.
Artigo em Inglês | MEDLINE | ID: mdl-29941558

RESUMO

Fast charging is a key enabler of mainstream adoption of electric vehicles (EVs). None of today's EVs can withstand fast charging in cold or even cool temperatures due to the risk of lithium plating. Efforts to enable fast charging are hampered by the trade-off nature of a lithium-ion battery: Improving low-temperature fast charging capability usually comes with sacrificing cell durability. Here, we present a controllable cell structure to break this trade-off and enable lithium plating-free (LPF) fast charging. Further, the LPF cell gives rise to a unified charging practice independent of ambient temperature, offering a platform for the development of battery materials without temperature restrictions. We demonstrate a 9.5 Ah 170 Wh/kg LPF cell that can be charged to 80% state of charge in 15 min even at -50 °C (beyond cell operation limit). Further, the LPF cell sustains 4,500 cycles of 3.5-C charging in 0 °C with <20% capacity loss, which is a 90× boost of life compared with a baseline conventional cell, and equivalent to >12 y and >280,000 miles of EV lifetime under this extreme usage condition, i.e., 3.5-C or 15-min fast charging at freezing temperatures.

5.
Proc Biol Sci ; 287(1926): 20200470, 2020 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-32370674

RESUMO

The cuticle of ecdysozoans (Panarthropoda, Scalidophora, Nematoida) is secreted by underlying epidermal cells and renewed via ecdysis. We explore here the relationship between epidermis and external cuticular ornament in stem-group scalidophorans from the early Cambrian of China (Kuanchuanpu Formation; ca 535 Ma) that had two types of microscopic polygonal cuticular networks with either straight or microfolded boundaries. Detailed comparisons with modern scalidophorans (priapulids) indicate that these networks faithfully replicate the cell boundaries of the epidermis. This suggests that the cuticle of early scalidophorans formed through the fusion between patches of extracellular material secreted by epidermal cells, as observed in various groups of present-day ecdysozoans, including arthropods. Key genetic, biochemical and mechanical processes associated with ecdysis and cuticle formation seem to have appeared very early (at least not later than 535 Ma) in the evolution of ecdysozoans. Microfolded reticulation is likely to be a mechanical response to absorbing contraction exerted by underlying muscles. The polygonal reticulation in early and extant ecdysozoans is clearly a by-product of the epidermal cell pavement and interacted with the sedimentary environment.


Assuntos
Artrópodes , Células Epidérmicas , Animais , Evolução Biológica , China , Epiderme , Fósseis , Muda , Filogenia
6.
J Environ Manage ; 265: 110549, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32275251

RESUMO

A site experiment was conducted to assess temporal dynamics of soil organic carbon (SOC) and the drivers under no-tillage (NT) and residue retention (RR) in the North China Plain (NCP). The results indicated that NT and RR can significantly increase SOC up to a depth of 30 cm. On average, NT increased SOC by 8.1-34.5% compared with PT, and RR increased SOC by 3.5-14.4% compared with R0 at 0-10 cm. Increases in SOC under NT or RR could be increased by 4-10 percentage points through the significantly positive interactions of NT and RR. Among the sources of SOC variations, tillage-induced variations accounted for 74.4 and 44.3% of the total variations in SOC at 0-5 cm for wheat and maize season, respectively. Experimental duration was also a significant source of variation. Stepwise regression indicated dynamics in SOC at 0-5 cm mainly due to the positive effects of precipitation, the negative effects of soil bulk density for the wheat season, the negative effects of radiation for the maize season, and antagonistic effects of temperature between wheat and maize season. Generally, positive effects of NT and RR on SOC were both confirmed, but fluctuations and variations induced by interactions of practices and seasonal climatic conditions were also significant in the NCP.


Assuntos
Solo , Triticum , Agricultura , Carbono , China , Zea mays
7.
Pharmazie ; 75(9): 412-416, 2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-32797765

RESUMO

Recent studies have shown that monoamine oxidase A (MAOA) is significantly expressed in malignant prostate cancer (PCa) and plays an important role in tumorigenesis indicating its potential to serve as a target for PCa treatment. Here, we choose the small molecule isoniazid as the MAOA inhibition functionality and incorporated it in the tumor-targeting moiety of heptamethine carbocyanine dyes via a pH sensitive hydrazone bond to design and synthesize novel MAOA inhibitor isoniazid-heptamethine carbocyanine dye conjugates. Cytotoxicity assay in PC-3 cells shows that all conjugates possessed improved antitumor efficacy compared with isoniazid. The tested compounds also demonstrated a moderate MAOA inhibitory effect. In conclusion, these results indicate that these conjugates exert antitumor effects by delivering the MAOA-inhibiting moiety to PCa cells.


Assuntos
Carbocianinas/química , Isoniazida/farmacologia , Inibidores da Monoaminoxidase/farmacologia , Neoplasias da Próstata/tratamento farmacológico , Antineoplásicos/administração & dosagem , Antineoplásicos/química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Sistemas de Liberação de Medicamentos , Humanos , Concentração de Íons de Hidrogênio , Isoniazida/administração & dosagem , Isoniazida/química , Masculino , Inibidores da Monoaminoxidase/administração & dosagem , Inibidores da Monoaminoxidase/química , Neoplasias da Próstata/patologia
8.
Zhongguo Dang Dai Er Ke Za Zhi ; 22(12): 1320-1325, 2020 Dec.
Artigo em Zh | MEDLINE | ID: mdl-33328004

RESUMO

A boy, aged 2 years and 4 months, had a sudden onset of blepharoptosis of the right eyelid, accompanied by the mouth deviated to the right side, drinking cough, nystagmus, and developmental regression. Cranial MRI showed softening lesions formed after infarction of the right dorsolateral medulla oblongata, while head CT angiography showed no imaging of the proximal part of the V4 segment of the right vertebral artery. The child was diagnosed with dorsolateral medulla oblongata syndrome and was treated with gamma globulin to regulate immune function, with mannitol to reduce neuronal edema, with low-molecular-weight heparin sodium to improve local hypercoagulation of occluded blood vessels, with hyperbaric oxygen to improve local ischemia and hypoxia and promote the recovery of brain function, and with neuromuscular electrical stimulation to promote the recovery of neuromuscular function. Before discharge, only mild right ataxia and Horner syndrome remained. This article reports the first case of infantile dorsolateral medulla oblongata syndrome and provides experience for the diagnosis and treatment of the disease.


Assuntos
Blefaroptose/etiologia , Disartria/etiologia , Síndrome Medular Lateral/diagnóstico , Bulbo/diagnóstico por imagem , Pré-Escolar , Humanos , Síndrome Medular Lateral/complicações , Imageamento por Ressonância Magnética , Masculino
9.
Proc Biol Sci ; 286(1906): 20190791, 2019 07 10.
Artigo em Inglês | MEDLINE | ID: mdl-31288707

RESUMO

With millions of extant species, ecdysozoans (Scalidophora, Nematoida and Panarthropoda) constitute a major portion of present-day biodiversity. All ecdysozoans secrete an exoskeletal cuticle which must be moulted periodically and replaced by a larger one. Although moulting (ecdysis) has been recognized in early Palaeozoic panarthropods such as trilobites and basal groups such as anomalocaridids and lobopodians, the fossil record lacks clear evidence of ecdysis in early scalidophorans, largely because of difficulties in recognizing true exuviae. Here, we describe two types of exuviae in microscopic scalidophoran worms from the lowermost Cambrian Kuanchuanpu Formation ( ca 535 Ma) of China and reconstruct their moulting process. These basal scalidophorans moulted in a manner similar to that of extant priapulid worms, extricating themselves smoothly from their old tubular cuticle or turning their exuviae inside out like the finger of a glove. This is the oldest record of moulting in ecdysozoans. We also discuss the origin of ecdysis in the light of recent molecular analyses and the significance of moulting in the early evolution of animals.


Assuntos
Fósseis , Invertebrados/crescimento & desenvolvimento , Muda , Animais , Evolução Biológica
10.
Molecules ; 24(7)2019 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-30974737

RESUMO

Monoamine oxidase A (MAOA) is an important mitochondria-bound enzyme that catalyzes the oxidative deamination of monoamine neurotransmitters. Accumulating evidence suggests a significant association of increased MAOA expression and advanced high-grade prostate cancer (PCa) progression and metastasis. Herein, a series of novel conjugates combining the MAOA inhibitor isoniazid (INH) and tumor-targeting near-infrared (NIR) heptamethine cyanine dyes were designed and synthesized. The synthesized compounds G1⁻G13 were evaluated in vitro for their cytotoxicity against PC-3 cells using the MTT assay, and molecular docking studies were performed. Results showed that most tested compounds exhibited improved antitumor efficacy compared with INH. Moreover, conjugates G10 and G11 showed potent anticancer activity with IC50 values (0.85 and 0.4 µM respectively) comparable to that of doxorubicin (DOX). This may be attributable to the preferential accumulation of these conjugates in tumor cells. G10, G11, and G12 also demonstrated moderate MAOA inhibitory activities. This result and the results of molecular docking studies were consistent with their cytotoxicity activities. Taken together, these data suggest that a combination of the MAOA inhibitor INH with tumor-targeting heptamethine cyanine dyes may prove to be a highly promising tool for the treatment of advanced prostate cancer.


Assuntos
Carbocianinas , Corantes Fluorescentes , Isoniazida , Simulação de Acoplamento Molecular , Inibidores da Monoaminoxidase , Monoaminoxidase , Proteínas de Neoplasias , Neoplasias da Próstata , Carbocianinas/síntese química , Carbocianinas/química , Carbocianinas/farmacologia , Corantes Fluorescentes/síntese química , Corantes Fluorescentes/química , Corantes Fluorescentes/farmacologia , Humanos , Isoniazida/química , Isoniazida/farmacologia , Masculino , Monoaminoxidase/química , Monoaminoxidase/metabolismo , Inibidores da Monoaminoxidase/síntese química , Inibidores da Monoaminoxidase/química , Inibidores da Monoaminoxidase/farmacologia , Proteínas de Neoplasias/antagonistas & inibidores , Proteínas de Neoplasias/metabolismo , Células PC-3 , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/enzimologia , Neoplasias da Próstata/patologia
11.
Apoptosis ; 22(11): 1404-1418, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28864870

RESUMO

The pro-inflammatory cytokine interleukin 6 (IL-6), via activating its downstream JAK/STAT3 and Ras/ERK signaling pathways, is involved in cell growth, proliferation and anti-apoptotic activities in various malignancies. To screen inhibitors of IL-6 signaling, we constructed a STAT3 and ERK dual-pathway responsive luciferase reporter vector (Co.RE). Among several candidates, the natural compound 20(S)-25-methoxyl-dammarane-3ß, 12ß, 20-triol (25-OCH3-PPD, GS25) was identified to clearly inhibit the luciferase activity of Co.RE. GS25 was confirmed to indeed inhibit activation of both STAT3 and ERK pathways and expression of downstream target genes of IL-6, and to predominantly decrease the viability of HepG2 cells via induction of cell cycle arrest and apoptosis. Interestingly, GS25 showed preferential inhibition of HepG2 cell viability relative to normal liver L02 cells. Further investigation showed that GS25 could not induce apoptosis and block activation of STAT3 and ERK pathways in L02 cells as efficiently as in HepG2 cells, which may result in differential effects of GS25 on malignant and normal liver cells. In addition, GS25 was found to potently suppress the expression of endogenous STAT3 at a higher concentration and dramatically induce p38 phosphorylation in HepG2 cells, which could mediate its anti-cancer effects. Finally, we demonstrated that GS25 also inhibited tumor growth in HepG2 xenograft mice. Taken together, these findings indicate that GS25 elicits its anti-cancer effects on HepG2 cells through multiple mechanisms and has the potential to be used as an inhibitor of IL-6 signaling. Thus, GS25 may be developed as a treatment for hepatocarcinoma with low toxicity on normal liver tissues as well as other inflammation-associated diseases.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Regulação Neoplásica da Expressão Gênica , Ginsenosídeos/farmacologia , Hepatoblastoma/tratamento farmacológico , Neoplasias Hepáticas/tratamento farmacológico , Fator de Transcrição STAT3/genética , Animais , Antineoplásicos Fitogênicos/síntese química , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Ciclo Celular/genética , Proliferação de Células/efeitos dos fármacos , Feminino , Genes Reporter , Vetores Genéticos/química , Vetores Genéticos/metabolismo , Ginsenosídeos/química , Células Hep G2 , Hepatoblastoma/genética , Hepatoblastoma/metabolismo , Hepatoblastoma/patologia , Humanos , Interleucina-6/genética , Interleucina-6/metabolismo , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Luciferases/genética , Luciferases/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Camundongos , Camundongos Nus , Fator de Transcrição STAT3/agonistas , Fator de Transcrição STAT3/metabolismo , Carga Tumoral/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto , Proteínas Quinases p38 Ativadas por Mitógeno/genética , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
12.
Neurol Sci ; 38(8): 1393-1403, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28593527

RESUMO

The study aimed to investigate the correlations of CACNA1C genetic polymorphisms and protein expression with the pathogenesis of schizophrenia in a Chinese population. This research included 139 patients diagnosed with schizophrenia (case group) and 141 healthy volunteers (control group). Case and control samples were genotyped using denaturing high-performance liquid chromatography (DHPLC). Haplotypes of rs10848683, rs2238032, and rs2299661 were analyzed using the Shesis software. A mouse model of schizophrenia was established and assigned to test and blank groups. Western blotting was used to detect CACNA1C protein expression. The genotype and allele distribution of rs2238032 and rs2299661 differed between the case and control groups. TT genotype of rs2238032 and G allele of rs2299661 could potentially reduce the risk of schizophrenia. The distribution of rs2238032 genotype has a close connection with cognitive disturbance and the results of the general psychopathology classification exam. The distribution of rs2299661 genotypes was closely related to sensory and perceptual disorders, negative symptom subscales, and the results of the general psychopathology classification exam. CTC haplotype increased and CTG decreased the risk of schizophrenia in healthy people. In the brain tissues of mice with schizophrenia, the CACNA1C protein expression was higher in the test group than in the blank group. Our study demonstrated that CACNA1C gene polymorphisms and CACNA1C protein expression were associated with schizophrenia and its clinical phenotypes.


Assuntos
Canais de Cálcio Tipo L/genética , Canais de Cálcio Tipo L/metabolismo , Predisposição Genética para Doença/genética , Polimorfismo de Nucleotídeo Único/genética , Esquizofrenia/genética , Esquizofrenia/metabolismo , Adulto , Animais , Povo Asiático , Encéfalo/metabolismo , Encéfalo/patologia , Estudos de Casos e Controles , Análise Mutacional de DNA , Modelos Animais de Doenças , Feminino , Frequência do Gene , Estudos de Associação Genética , Genótipo , Humanos , Masculino , Camundongos , Fenótipo , Escalas de Graduação Psiquiátrica , Esquizofrenia/etnologia , Esquizofrenia/patologia
13.
Biomed Environ Sci ; 30(6): 391-397, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28705262

RESUMO

OBJECTIVE: To determine the dietary zinc absorption in a Chinese elderly population and provide the basic data for the setting of zinc (Zn) recommended nutrient intakes (RNI) for Chinese elderly people. METHODS: A total of 24 elderly people were recruited for this study and were administered oral doses of 3 mg 67Zn and 1.2 mg dysprosium on the fourth day. The primary macronutrients, energy, and phytic acid in the representative diet were examined based on the Chinese National Standard Methods. Fecal samples were collected during the experimental period and analyzed for zinc content, 67Zn isotope ratio, and dysprosium content. RESULTS: The mean (± SD) zinc intake from the representative Chinese diet was 10.6 ± 1.5 mg/d. The phytic acid-to-zinc molar ratio in the diet was 6.4. The absorption rate of 67Zn was 27.9% ± 9.2%. The RNI of zinc, which were calculated by the absorption rate in elderly men and women, were 10.4 and 9.2 mg/d, respectively. CONCLUSION: This study got the dietary Zn absorption in a Chinese elderly population. We found that Zn absorption was higher in elderly men than in elderly women. The current RNI in elderly female is lower than our finding, which indicates that more attention is needed regarding elderly females' zinc status and health.


Assuntos
Povo Asiático , Dieta , Zinco/farmacocinética , Idoso , Disponibilidade Biológica , China , Disprósio , Elementos Químicos , Fezes/química , Feminino , Humanos , Absorção Intestinal , Masculino , Refeições , Pessoa de Meia-Idade , Fenômenos Fisiológicos da Nutrição , Zinco/química , Isótopos de Zinco
14.
Br J Nutr ; 115(1): 24-31, 2016 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-26522081

RESUMO

Increasing dietary Ca intake may prevent the excessive mobilisation of bone mineral in nursing mothers. We aimed to investigate whether higher Ca intake could positively modulate the bone mineral changes in Chinese postpartum lactating women. The study was a 12-month randomised, double-blinded, parallel group trial conducted over 12 months. A total of 150 postpartum women were randomly selected to receive either 40 g of milk powder containing 300 mg of Ca and 5 µg of vitamin D (Low-Ca group) or same milk powder additionally fortified with 300 mg of Ca (Mid-Ca group) or 600 mg of Ca (High-Ca group). Bone mineral density (BMD) for the whole body, the lumbar spine, the total left hip and its sub-regions was measured using dual-energy X-ray absorptiometry. A total of 102 subjects completed the whole trial. The duration of total lactating time was 7·9 (SD 2·8) months on average. The intention-to-treat analysis yielded the following mean percentage changes in BMD for the whole body, the lumbar spine and the total left hip, respectively: -0·93 (SD 1·97), 2·11 (SD 4·90) and -1·60 (SD 2·65)% for the Low-Ca group; -0·56 (SD 1·89), 2·21 (SD 3·77) and -1·43 (SD 2·30)% for the Mid-Ca group; and -0·44 (SD 1·67), 2·32 (SD 4·66) and -0·95 (SD 4·08)% for the High-Ca group. The differences between the groups were not statistically significant (P: 0·5-0·9). The results of the complete case analysis were similar. In sum, we found no significant differences in the bone mineral changes from baseline to 12 months in postpartum lactating women consuming milk powder fortified with different levels of Ca.


Assuntos
Densidade Óssea , Osso e Ossos/efeitos dos fármacos , Aleitamento Materno , Cálcio da Dieta/farmacologia , Cálcio/farmacologia , Suplementos Nutricionais , Lactação/metabolismo , Absorciometria de Fóton , Adulto , Animais , Osso e Ossos/metabolismo , Calcificação Fisiológica , Cálcio/administração & dosagem , Cálcio/metabolismo , Cálcio da Dieta/administração & dosagem , Cálcio da Dieta/metabolismo , Método Duplo-Cego , Feminino , Alimentos Fortificados , Quadril , Humanos , Vértebras Lombares , Leite , Minerais/metabolismo , Minerais/farmacologia , Período Pós-Parto , Vitamina D/farmacologia , Adulto Jovem
15.
Biomed Environ Sci ; 29(11): 829-833, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27998390

RESUMO

Iron deficiency anemia is one of the most prevalent nutritional deficiency worldwide. The commonly used cut-off values for identifying iron deficiency are extrapolated from older children and may not be suitable for infants. Therefore, our study aimed to establish appropriate cut-off values for the evaluation of iron status in Chinese infants. Pregnant women who delivered at ⋝37 gestational weeks with normal iron status were recruited. Later, infants with normal birth weight and who were breastfed in the first 4 months were selected. Blood samples were collected to assess hemoglobin, serum ferritin, soluble transferrin receptor, mean corpuscular volume and free erythrocyte protoporphyrin. Cut-offs of all iron indices were determined as the limit of 95% confidence interval.


Assuntos
Anemia Ferropriva/diagnóstico , Anemia Ferropriva/sangue , Aleitamento Materno , China , Humanos , Lactente , Valores de Referência
16.
Biomed Environ Sci ; 29(3): 165-76, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27109127

RESUMO

OBJECTIVE: To describe the undernutrition status of children under 5-year in China, and study the trend between 2002 and 2013). METHODS: The study was based on two national surveys. Undernutrition was determined against WHO's 2006 growth standards. The prevalence in 2013 and 2002 was weighted by China sixth National Population Census (2010). The relationship between undernutrition and gender/age groups/different areas use weighted logistic regression. RESULTS: The results indicated the overall prevalence of stunting, underweight, and wasting of Chinese children under 5-year was 8.1%, 2.4%, and 1.9% in 2013, respectively. The prevalence of stunting was higher for children aged 12-47 month, while underweight was higher for children aged 48-59 month. The prevalence of undernutrition was higher in rural areas than in urban areas, especially in poor rural areas. There was a decline of stunting, underweight, and wasting between 2002 and 2013 among the children, with greater reduction in rural areas than in urban areas. CONCLUSION: The prevalence of undernutrition of children under 5-year remains high in rural areas especially in poor rural areas in China. It is urgent to take action to control undernutrition in the vulnerable areas and subgroups.


Assuntos
Transtornos da Nutrição Infantil/epidemiologia , Desnutrição/epidemiologia , Fenômenos Fisiológicos da Nutrição Infantil , Pré-Escolar , China/epidemiologia , Feminino , Humanos , Lactente , Masculino , Prevalência , Magreza , Fatores de Tempo
17.
J Craniofac Surg ; 27(6): 1600-5, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27391658

RESUMO

The mechanism of cleft palate induction by dexamethasone is not fully known. Bone morphogenetic protein-2 (BMP-2) has been associated with dexamethasone-induced osteoporosis. In this study, the authors induced cleft palate models in Institute of Cancer Research mice by dexamethasone to investigate the role of BMP-2 and its transcriptional element GATA-6. The authors injected different doses of dexamethasone into pregnant mice (E13), and assessed the histology of the palatal shelf and the expression levels of BMP-2, GATA-6, and specific apoptosis-related proteins. The results showed that cleft palate formation was dependent on dexamethasone dosage, with high incidence (50.55%) at high concentration (50 mg/kg) compared with the low doses (6 mg/kg, 38.10%). Transmission electron microscopy revealed significant cellular changes of the cleft palate shelf, including loose cell connection, cellular swelling, as well as reduced extracellular matrix and mitochondria. Following exposure to dexamethasone, the apoptotic rate in the palate increased with elevated dosage. Western blotting analysis indicated that the expression levels of GATA-6 and BMP-2 were reduced, while the levels of apoptotic proteins bax and caspase-3 were increased. The results of authors' study suggested that dexamethasone-induced cleft palate formation involved apoptosis occurred in a dose-dependent manner. BMP-2 and GATA-6 mediated dexamethasone-induced cleft palate formation.


Assuntos
Proteína Morfogenética Óssea 2/fisiologia , Fissura Palatina/induzido quimicamente , Fissura Palatina/fisiopatologia , Dexametasona/farmacologia , Fator de Transcrição GATA6/fisiologia , Animais , Apoptose/fisiologia , Proteína Morfogenética Óssea 2/antagonistas & inibidores , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Feminino , Fator de Transcrição GATA6/antagonistas & inibidores , Injeções Intraperitoneais , Masculino , Camundongos , Camundongos Endogâmicos ICR , Gravidez
18.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 47(5): 708-713, 2016 Sep.
Artigo em Zh | MEDLINE | ID: mdl-28598084

RESUMO

OBJECTIVES: To study the effect of electroacupuncture with near-to-bone needling on the proliferation and apoptosis of knee osteoarthritis. METHODS: Totally 40 New Zealand rabbits were randomly divided into two groups, the normal group (A, n =10) and the modeling group (n =30). Hulth-Telhag method was applied 30 rabbits to establish rabbit left knee osteoarthritis model, and evaluated by X-ray after 6 weeks. Then divided the 30 modeling rabbits into electroacupuncture with near-to-bone needling group (C,n =10), electroacupuncture with ordinary needling group (D,n =10) and model group (B ,n =10) randomly. Four treatments (5 d as one course of treatment) were applied to C group and D group, respectively. At the end of the experiment, modeling situation was detected by X-ray, pathological changes of cartilage was detected by HE staining ,and apoptosis of chondrocytes was checked by TUNEL staining; mRNA expressions of Caspase-3 and proliferating cell unclear antigen (PCNA) in chondrocytes were detected by RT-PCR; protein expressions of Caspase-3, PCNA, Bcl-2 and Bax in chondrocytes were detected by Western blot. RESULTS: HE stain demonstrated that the chondrocytes of A group,C group and D group were arranged in a more regular and smooth surface when compared with B group. The expressions of Bcl-2 and PCNA in C and D groups were higher than those of B group, but the expression of Caspase-3 and Bax were lower, when evaluated with Western blot;increased expressions of PCNA and Bcl-2 but decreased expressions of Caspase-3 and Bax in C group were also noticed when compared with D group. RT-PCR results demonstrated that when compared with B group, the expression of PCNA mRNA were increased but Caspase-3 mRNA were decreased in C and D groups; compared with D group, the expression of PCNA mRNA were increased but Caspase-3 mRNA were decreased in C group. CONCLUSIONS: The electroacupuncture with near-to-bone needling method is superior to the electroacupuncture with ordinary needling in decreasing apoptosis and promoting proliferation of chondrocytes.


Assuntos
Apoptose , Condrócitos/citologia , Eletroacupuntura/métodos , Osteoartrite do Joelho/terapia , Animais , Caspase 3/metabolismo , Proliferação de Células , Antígeno Nuclear de Célula em Proliferação/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Coelhos , Proteína X Associada a bcl-2/metabolismo
19.
J Immunoassay Immunochem ; 36(2): 119-27, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-24702118

RESUMO

The study evaluated tuberculosis specific antigen (TB-SA) antibody in lymphocyte supernatant (ALS) assay for diagnosis of pulmonary tuberculosis (PTB). The mean concentration of TB-SA ALS in PTB patients was significantly higher than that of two control groups (non-PTB patients and healthy subjects, P < 0.001). The area under the curve of the ALS assay were 0.960 (0.904-0.988, PTB vs healthy subjects), and were 0.822 (0.739-0.887, PTB vs Non-PTB patients), respectively. Our data indicated the ALS assay for TB-SA can be used as a screening test and is a useful adjunct to current tests for diagnosis of PTB.


Assuntos
Anticorpos Antibacterianos/imunologia , Antígenos de Bactérias/imunologia , Bioensaio , Imunoglobulina G/imunologia , Mycobacterium tuberculosis/imunologia , Tuberculose Pulmonar/diagnóstico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Leucócitos Mononucleares/imunologia , Neoplasias Pulmonares/imunologia , Masculino , Mesotelioma/imunologia , Pessoa de Meia-Idade , Tuberculose Pulmonar/imunologia , Adulto Jovem
20.
Biomed Environ Sci ; 28(10): 738-50, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26582096

RESUMO

OBJECTIVE: To determine ten B-vitamins in human milk by ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). METHODS: The pretreated human milk samples were adequately separated and quantified within 11 min by UPLC-MS/MS with an Acquity UPLC HSS T3 column (2.1×100 mm, 1.8 µm). The mobile phase was a gradient of 2.5 mmol/L ammonium formate aqueous solution and acetonitrile at a flow rate of 0.35 mL/min. Stable isotope internal standards were used in the analysis, to correct for the method variability, including matrix and ionization effects. The homogenized human milk samples were deproteinzed using methanol, unknown contaminants were extracted with diethyl ether and hydrophobic phase was discarded. The analytes were monitored via ESI+ionization and detected in multiple reaction monitoring (MRM) with three acquisition functions. RESULTS: Calibration curves ranged from 0.5-160 ng/mL (thiamin, riboflavin, biotin, nicotinic acid, pyridoxine, pyridoxamine, pyridoxal), and 2.5-800 ng/mL (pantothenic acid, FAD and nicotinamide) (R2=0.990-0.999). The relative recovery ranged from 80.1% to 120.2%; accuracy was determined to be 98.3% to 108.0%. Intra-day and inter-day variation were 3.4%-19.9% and 5.9%-18.1%, respectively. The limit of quantification (LOQ) for all vitamins was between 0.25 and 3 µg/L. CONCLUSION: This method was successfully applied for simultaneous analysis of ten B-vitamins in human milk.


Assuntos
Cromatografia Líquida/métodos , Leite Humano/química , Espectrometria de Massas em Tandem/métodos , Complexo Vitamínico B/química , Humanos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
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