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1.
Proc Natl Acad Sci U S A ; 117(19): 10414-10421, 2020 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-32350143

RESUMO

The rise of oxygen on the early Earth about 2.4 billion years ago reorganized the redox cycle of harmful metal(loids), including that of arsenic, which doubtlessly imposed substantial barriers to the physiology and diversification of life. Evaluating the adaptive biological responses to these environmental challenges is inherently difficult because of the paucity of fossil records. Here we applied molecular clock analyses to 13 gene families participating in principal pathways of arsenic resistance and cycling, to explore the nature of early arsenic biogeocycles and decipher feedbacks associated with planetary oxygenation. Our results reveal the advent of nascent arsenic resistance systems under the anoxic environment predating the Great Oxidation Event (GOE), with the primary function of detoxifying reduced arsenic compounds that were abundant in Archean environments. To cope with the increased toxicity of oxidized arsenic species that occurred as oxygen built up in Earth's atmosphere, we found that parts of preexisting detoxification systems for trivalent arsenicals were merged with newly emerged pathways that originated via convergent evolution. Further expansion of arsenic resistance systems was made feasible by incorporation of oxygen-dependent enzymatic pathways into the detoxification network. These genetic innovations, together with adaptive responses to other redox-sensitive metals, provided organisms with novel mechanisms for adaption to changes in global biogeocycles that emerged as a consequence of the GOE.

2.
Aust N Z J Psychiatry ; : 4867420917449, 2020 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-32436725

RESUMO

OBJECTIVE: Antipsychotics are widely used for treating psychosis, but it is unclear whether they can also prevent psychosis. This study attempted a longitudinal evaluation of antipsychotics under real-world conditions in China to evaluate their effect on the rate of conversion to psychosis in individuals with a clinical high risk (CHR) of psychosis. METHOD: A total of 517 CHR individuals were recruited between 2011 and 2016 and followed up for 3 years. Among these, 450 (87.0%) individuals completed follow-up, 108 (24.0%) showed conversion to psychosis and 309 (68.7%) received antipsychotics. The main outcome was conversion to psychosis. The sample was further stratified according to the severity of positive symptoms. RESULTS: Patients who did not receive antipsychotics showed a lower conversion rate than those who did (17.7% vs 26.9%; odds ratio [OR] = 0.660, 95% confidence interval [CI] = [0.442, 0.985], p = 0.035). In mild CHR cases, antipsychotic treatment was more likely to be associated with conversion to psychosis, compared with the no-antipsychotics group, with no such difference observed in severe CHR cases. Among those who received antipsychotics, monotherapy or low-dose treatment was associated with lower conversion rates. Our results did not favor any specific type of antipsychotics and suggested that a very small subgroup of CHR individuals with severe positive and general symptoms but mild negative symptoms may benefit from antipsychotic treatment. CONCLUSIONS: Administration of antipsychotics to CHR patients is potentially harmful with no preventive benefits. We do not recommend antipsychotic treatment for CHR individuals, which is practiced widely in China, and strongly advise caution if these drugs are used.

3.
Psychol Med ; : 1-9, 2020 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-32248862

RESUMO

BACKGROUND: Age effects may be important for improving models for the prediction of conversion to psychosis for individuals in the clinical high risk (CHR) state. This study aimed to explore whether adolescent CHR individuals (ages 9-17 years) differ significantly from adult CHR individuals (ages 18-45 years) in terms of conversion rates and predictors. METHOD: Consecutive CHR individuals (N = 517) were assessed for demographic and clinical characteristics and followed up for 3 years. Individuals with CHR were classified as adolescent (n = 244) or adult (n = 273) groups. Age-specific prediction models of psychosis were generated separately using Cox regression. RESULTS: Similar conversion rates were found between age groups; 52 out of 216 (24.1%) adolescent CHR individuals and 55 out of 219 (25.1%) CHR adults converted to psychosis. The conversion outcome was best predicted by negative symptoms compared to other clinical variables in CHR adolescents (χ2 = 7.410, p = 0.006). In contrast, positive symptoms better predicted conversion in CHR adults (χ2 = 6.585, p = 0.01). CONCLUSIONS: Adolescent and adult CHR individuals may require a different approach to early identification and prediction. These results can inform the development of more precise prediction models based on age-specific approaches.

5.
Tree Physiol ; 2020 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-32159802

RESUMO

Seed dormancy is crucial for plant survival and prevents seed germination out of season. However, little is known about the regulatory mechanism of morphophysiological seed dormancy. Ginkgo biloba is one of the most ancient gymnosperms, and the completion of seed germination in this species requires cold and moist stratification. Here, we observed that at the mature seed stage, the embryo was not fully developed in G. biloba seeds. During dormancy stages, the length and weight of the embryo significantly increased, and nutrients accumulated in cotyledons. We further found that abscisic acid (ABA), gibberellic acid (GA), cytokinin, and ethylene were integrated in the seed dormancy induction, maintenance, and release processes, and GA biosynthesis and signaling transduction specifically act on dormancy release. Combining mRNA and miRNA analyses, we demonstrated that miRNA156 is involved in regulation of morphophysiological dormancy. Our analyses revealed that G. biloba seed dormancy belongs to the ancestral morphophysiological dormancy type, which is not only regulated by the balance of ABA/GA, but also by other hormones associated with embryo morphological development, as well as genes related to embryo differentiation and development. These findings helped with elucidating the comprehensive regulatory network of morphophysiological dormancy in tree seeds.

6.
J Ethnopharmacol ; 256: 112784, 2020 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-32222573

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Ilicis Rotundae Cortex (IRC), a Chinese crude drug, has been widely utilized in Guangdong and Guangxi provinces of China to treat or prevent cardiovascular diseases. AIM OF STUDY: This investigation aims to study the lipid-lowering effect of IRC, as well as the regulating effect on the endogenous metabolites in hyperlipidemia rats. MATERIALS AND METHODS: High-fat diet induced hyperlipidemia rats were administrated with different doses of IRC extract (0.5, 1.0 and 2.0 g/kg/day) for 5 weeks. Simvastatin was used as the positive control. Body weight, serum lipid levels and histopathology of liver were evaluated. The metabolic profiles of plasma, urine and cecum content were analyzed using UPLC/Q-TOF-MS/MS-based metabolomics approach coupled with multivariate data analysis. RESULTS: The levels of serum TC, TG, LDL-C, AST and ALT were significantly decreased and HDL-C level was increased in IRC treatment groups. The hepatic histomorphology was partially restored. 23, 26 and 15 metabolites in plasma, urine and cecum content were determined as the biological biomarkers, respectively. IRC extract could partially recover the disturbed metabolic pathways of bile acid metabolism, linoleic acid metabolism, arachidonic acid metabolism, taurine and hypotaurine metabolism, glyoxylate and dicarboxylate metabolism, glycerophospholipid metabolism, synthesis and degradation of ketone bodies, sphingolipid metabolism and riboflavin metabolism. CONCLUSION: This study demonstrated that IRC could effectively improve the serum lipids and partially restore the hepatic histomorphology. The underlying metabolic mechanism mainly included improving the metabolism of bile acids, glycerophospholipid, sphingolipid, fatty acid and amino acid. This is the first study on the lipid-lowering effect of IRC from the perspective of metabolomics.

7.
Fitoterapia ; 143: 104561, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32199959

RESUMO

Two new compounds, named penisclerotiorin A (1) and diaporthein C (8), and a new natural product, penidepsidone A (4), together with five known compounds (2, 3, 5-7) were isolated from the fungus Penicillium sclerotiorum GZU-XW03-2. Their structures were assigned using spectroscopic methods, quantum chemical calculations, and single-crystal X-ray diffraction analysis. Penisclerotiorin A (1) that belongs to the highly oxidized diphenyl ether is rare found in natural sources, and it was the sixth example of highly oxidized diphenyl ether analogues in natural sources. Penidepsidone A (4) is a new natural product and no any NMR spectral data were reported to date, in this paper, we firstly used the NMR calculations to confirm the intact structure by comparison of the experimental NMR data. Diaporthein C (8) represents the third example of pimarane diterpenes bearing a double bond at C-8 and C-9. In the bioassays, all of the isolates (1-8) were tested for their anti-inflammatory effects on the production of nitric oxide in lipopolysaccharide-induced microglial cells (RAW 264.7 cells). Compounds 2, 3 and 6 showed potent anti-inflammatory effects than the positive control (indomethacin, IC50, 24.0 µM) with IC50 values of 11.52, 8.13 and 21.27 µM, respectively.

8.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 51(2): 131-138, 2020 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-32220177

RESUMO

This review summarizes the ongoing researches regarding etiology, epidemiology, transmission dynamics, treatment, and prevention and control strategies of the coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), with comparison to severe acute respiratory syndrome coronavirus (SARS-CoV), Middle East respiratory syndrome coronavirus (MERS-CoV) and pandemic H1N1 virus. SARS-CoV-2 may be originated from bats, and the patients and asymptomatic carriers are the source of epidemic infection. The virus can be transmitted human-to-human through droplets and close contact, and people at all ages are susceptible to this virus. The main clinical symptoms of the patients are fever and cough, accompanied with leukocytopenia and lymphocytopenia. Effective drugs have been not yet available thus far. In terms of the prevention and control strategies, vaccine development as the primary prevention should be accelerated. Regarding the secondary prevention, ongoing efforts of the infected patients and close contacts quarantine, mask wearing promotion, regular disinfection in public places should be continued. Meanwhile, rapid detection kit for serological monitoring of the virus in general population is expected so as to achieve early detection, early diagnosis, early isolation and early treatment. In addition, public health education on this disease and prevention should be enhanced so as to mitigate panic and mobilize the public to jointly combat the epidemic.


Assuntos
Betacoronavirus , Infecções por Coronavirus , Pandemias , Pneumonia Viral , Doenças Assintomáticas , Betacoronavirus/patogenicidade , Técnicas de Laboratório Clínico , Infecções por Coronavirus/complicações , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/prevenção & controle , Infecções por Coronavirus/transmissão , Tosse/etiologia , Diagnóstico Precoce , Febre/etiologia , Humanos , Vírus da Influenza A Subtipo H1N1 , Leucopenia/etiologia , Linfopenia/etiologia , Coronavírus da Síndrome Respiratória do Oriente Médio , Pandemias/prevenção & controle , Pneumonia Viral/complicações , Pneumonia Viral/epidemiologia , Pneumonia Viral/prevenção & controle , Pneumonia Viral/transmissão , Vírus da SARS , Prevenção Secundária , Vacinas Virais
9.
Arch Biochem Biophys ; 683: 108322, 2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-32113875

RESUMO

Post-burn hypertrophic scar (HTS) is a form of excessive dermal fibrosis characterized by cutaneous scarring, which is common in patients following burn injury. Moreover, at least 50% of HTS are accompanied by inflammation. Cytoplasmic polyadenylation element binding (CPEB) proteins are key mRNA-binding proteins that control the translation of several mRNAs. However, their potential roles in treating dermal fibrosis and scarring remain unknown. Therefore, in this study, we aimed to investigate the effects of small interfering RNA (siRNA)-mediated knockdown of CPEB1 or CPEB4 in human THP-1 macrophages and dermal fibroblasts treated with LPS and TGF-ß1. We found significantly increased CPEB1 and CPEB4 mRNA and protein levels in LPS-treated THP-1 cells and TGF-ß1-treated fibroblasts. CPEB1 and CPEB4 knockdowns suppressed LPS-activated TAK1 signaling cascades by reducing the levels of TNF-α and phosphorylated TAK1, p38, ERK, JNK, and NF-κB-p65 in THP-1 cells. CPEB1 and CPEB4 knockdowns also attenuated TGF-ß1-activated Smad-dependent and -independent signaling cascades by reducing the levels of TAK1, p38, ERK, JNK, and phosphorylated Smad 2 and Smad 1/5/8 in fibroblasts. Furthermore, CPEB1 or CPEB4 knockdown markedly decreased the levels of fibrosis markers, including α-SMA, type I collagen, and fibronectin in fibroblasts. Our findings indicate that CPEB1 and CPEB4 are involved in the regulation of the TAK1 and Smad signalings in human macrophages and dermal fibroblasts. These activities may play a role in cutaneous scarring responses.

10.
Artigo em Inglês | MEDLINE | ID: mdl-32003210

RESUMO

For the first time, we report the successful fabrication of well-behaved field-effect transistors based on Nb-doped ß-Ga2O3 nanobelts mechanically exfoliated from bulk single crystals. The exfoliated ß-Ga2O3 nanobelts were transferred onto a purified surface of the 110 nm SiO2/Si substrate. These Nb-doped devices showed excellent electrical performance such as an ultrasmall cutoff current of ∼10 fA, a high current on/off ratio of >108, and a quite steep subthreshold swing (SS, ∼120 mV/decade). Furthermore, we investigated the temperature dependence down to 200 K, providing insightful information for its operation in a harsh environment. This work lays a foundation for wider application of Nb-doped ß-Ga2O3 in nano-electronics.

11.
Org Lett ; 22(4): 1336-1339, 2020 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-32037840

RESUMO

Aspermeroterpene A (1) with an unprecedented and highly congested 5/3/6/6/6/5 hexacyclic skeleton, together with two precursors aspermeroterpenes B (2) and C (3), were isolated from the marine-derived fungus Aspergillus terreus GZU-31-1. Their structures were elucidated by quantum chemical calculations, X-ray diffraction, and spectroscopic methods. The biogenetic pathway for 1-3 is proposed. Aspermeroterpenes A-C (1-3) showed significant inhibitory activities against lipopolysaccharide (LPS)-induced nitric oxide (NO) production in RAW 264.7 cells compared to positive control.

12.
Medicine (Baltimore) ; 99(5): e18455, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32000358

RESUMO

INTRODUCTION: Whole brain radiotherapy (WBRT) has been the mainstay treatment of brain metastases (BM) in non-small cell lung cancer (NSCLC) patients for years. Temozolomide (TMZ) could penetrate the blood-brain barrier and some studies showed that TMZ plus MBRT may improve clinical effectiveness. This meta-analysis is aim to evaluate the clinical effectiveness and safety of TMZ plus MBRT in the NSCLC patients with BM. METHODS AND ANALYSIS: We systematically searched databases including PubMed, EMBASE, Cochrane Central Register of Controlled Trials, and four Chinese databases (Chinese Biomedical Database, China National Knowledge Infrastructure, Wanfang Database and Chinese Scientific Journal Database) without language restrictions from inception until July 26, 2019. Randomized controlled trials (RCTs) which compared TMZ plus WBRT with single WBRT in the advanced NSCLC patients with BM were included. The outcomes analysis reported objective response rate (ORR), disease control rate (DCR), overall survival (OS), progression-free survival (PFS), quality of life (QOL), and adverse effects. Two reviewers will independently extract data from the selected studies and assess the quality of studies. Statistical analyses will be performed using Review manager 5.3 software. Random-effects or fixed models were used to estimate pooled hazard ratio and relative risk. RESULTS: This systemic review and meta-analysis will evaluate the effects of TMZ plus MBRT in the NSCLC patients with BM in RCTs. CONCLUSION: Our study will provide evidence to judge if TMZ plus MBRT are effective treatment for NSCLC patients with BM.


Assuntos
Antineoplásicos Alquilantes/uso terapêutico , Neoplasias Encefálicas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Temozolomida/uso terapêutico , Neoplasias Encefálicas/radioterapia , Neoplasias Encefálicas/secundário , Carcinoma Pulmonar de Células não Pequenas/radioterapia , Carcinoma Pulmonar de Células não Pequenas/secundário , Humanos , Neoplasias Pulmonares/patologia , Metanálise como Assunto , Revisões Sistemáticas como Assunto
13.
Chem Commun (Camb) ; 56(21): 3183-3186, 2020 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-32067022

RESUMO

A novel nanoarchitecture (MSN-Tb-UbR) was prepared by modifying rhodamine B-labelled Ubs (Ub-Rs) on the surface of mesoporous silica nanoparticles (MSNs) loaded with Tb3+-complexes. The MSN-Tb-UbR exhibits ratiometric sensing ability for DUB (UCH-L1) with good sensitivity and selectivity.


Assuntos
Nanopartículas/química , Dióxido de Silício/química , Ubiquitina Tiolesterase/análise , Transferência Ressonante de Energia de Fluorescência/métodos , Corantes Fluorescentes/química , Porosidade , Rodaminas/química , Propriedades de Superfície , Térbio/química
14.
Chem Commun (Camb) ; 56(10): 1517-1520, 2020 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-31919484

RESUMO

The pseudoguaianelactones A (1) and B (2), two novel sesquiterpene lactones with an unprecedented [5,7,7] ring system featuring an α-methylene-γ-lactone moiety, together with a new pseudoguaianelactone C (3) were isolated from the roots of Lindera glauca. Pseudoguaianelactones A-C (1-3) inhibited nitric oxide (NO) production, with IC50 values ranging from 1.38 to 4.00 µM. Moreover, all compounds significantly suppressed the production of pro-inflammatory mediators (TNF-α, IL-6, IL-1ß and PGE2) and the protein expression of the enzymes iNOS and COX-2.


Assuntos
Anti-Inflamatórios/química , Ciclo-Oxigenase 2/metabolismo , Lindera/química , Óxido Nítrico Sintase Tipo II/metabolismo , Sesquiterpenos/química , Animais , Anti-Inflamatórios/isolamento & purificação , Anti-Inflamatórios/farmacologia , Cristalografia por Raios X , Citocinas/metabolismo , Lindera/metabolismo , Lipopolissacarídeos/farmacologia , Macrófagos/citologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Camundongos , Conformação Molecular , Óxido Nítrico/metabolismo , Raízes de Plantas/química , Raízes de Plantas/metabolismo , Células RAW 264.7 , Sesquiterpenos/isolamento & purificação , Sesquiterpenos/farmacologia
15.
Gut Microbes ; : 1-21, 2020 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-31983316

RESUMO

Methotrexate (MTX) is a typical chemotherapeutic drug that is widely used in the treatment of various malignant diseases as well as autoimmune diseases, with gastrointestinal toxicity being its most prominent complication which could have a significant effect on the prognosis of patients. Yet effective ways to alleviate such complications remains to be explored. Here we show that 30% dietary restriction (DR) for 2 weeks dramatically increased the survival rate of 2-month-old female mice after lethal-dose MTX exposure. DR significantly reduced intestinal inflammation, preserved the number of basal crypt PCNA-positive cells, and protected the function of intestinal stem cells (ISCs) after MTX treatment. Furthermore, ablating intestinal microbiota by broad-spectrum antibiotics completely eliminated the protective effect achieved by DR. 16S rRNA gene deep-sequencing analysis revealed that short-term DR significantly increased the Lactobacillus genus, with Lactobacillus rhamnosus GG gavage partially mimicking the rescue effect of DR on the intestines of ad libitum fed mice exposed to lethal-dose MTX. Together, the current study reveals that DR could be a highly effective way to alleviate the lethal injury in the intestine after high-dose MTX treatment, which is functionally mediated by increasing the protective intestinal microbiota taxa in mice. Keywords: Dietary restriction, Methotrexate, Gut microbiota, Intestinal stem cells, intestinal toxicity.

16.
J ECT ; 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31972667

RESUMO

BACKGROUND: Repetitive transcranial magnetic stimulation (rTMS) is now an established, safe, and effective treatment for adults with depression. However, specific research in rTMS for use in elderly patients with acute depression is scarce. OBJECTIVE: The aim of the present study was to investigate the efficacy of add-on rTMS in a clinical sample of older adults experiencing an acute phase of depression. METHOD: This study examined 114 patients (54 elderly [aged ≥60] and 60 adults [aged 18-59]) with acute depression who were drug free at baseline. They were treated with at least 10 sessions of rTMS for 4 weeks along with 1 antidepressant. Symptoms of depression were measured using the Hamilton Rating Scale for Depression at baseline and after 2 and 4 weeks of treatment. Clinical improvement and rates of response and remission were compared across groups. RESULTS: Significant improvement was noted after 2 and 4 weeks of treatment in both adult and elderly groups. Higher remission rates were found in adult patients but with no differences in response. The stimulation intensity and course of illness were significant predictors of remission after 4 weeks of rTMS treatment in the elderly. CONCLUSIONS: The add-on rTMS treatment for elderly depression patients is promising with respect to safety and feasibility. This preliminary evidence supports the application of rTMS to this group during acute episodes.

17.
Stem Cell Rev Rep ; 16(1): 212-221, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31797147

RESUMO

Aging is characterized by the accumulation of DNA damage and a decrease in stem cell functionality, yet molecular mechanisms that limit the maintenance of stem cells in response to DNA damage remain to be delineated. Here we show in mouse models that DNA damage leads to a transient over-activation of Wnt signaling in hematopoietic stem cells (HSCs), and that high activity of canonical Wnt/ß-catenin signaling sensitizes HSCs to DNA damage induced by X-irradiation which results in preferential maintenance of HSCs with low levels of Wnt signaling. The study shows that genetic or chemical activation of canonical Wnt signaling enhances radiosensitivity of HSCs while inhibition of Wnt signaling decreases it. Together, these results indicate that levels of Wnt signaling activity mediate heterogeneity in the sensitivity of HSCs to DNA damage induced depletion. These findings could be relevant for molecular alterations and selection of stem cells in the context of DNA damage accumulation during aging and cancer formation.

18.
Nucleic Acids Res ; 48(D1): D983-D991, 2020 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-31598699

RESUMO

Recent advances in genome sequencing and functional genomic profiling have promoted many large-scale quantitative trait locus (QTL) studies, which connect genotypes with tissue/cell type-specific cellular functions from transcriptional to post-translational level. However, no comprehensive resource can perform QTL lookup across multiple molecular phenotypes and investigate the potential cascade effect of functional variants. We developed a versatile resource, named QTLbase, for interpreting the possible molecular functions of genetic variants, as well as their tissue/cell-type specificity. Overall, QTLbase has five key functions: (i) curating and compiling genome-wide QTL summary statistics for 13 human molecular traits from 233 independent studies; (ii) mapping QTL-relevant tissue/cell types to 78 unified terms according to a standard anatomogram; (iii) normalizing variant and trait information uniformly, yielding >170 million significant QTLs; (iv) providing a rich web client that enables phenome- and tissue-wise visualization; and (v) integrating the most comprehensive genomic features and functional predictions to annotate the potential QTL mechanisms. QTLbase provides a one-stop shop for QTL retrieval and comparison across multiple tissues and multiple layers of molecular complexity, and will greatly help researchers interrogate the biological mechanism of causal variants and guide the direction of functional validation. QTLbase is freely available at http://mulinlab.org/qtlbase.

19.
J Anat ; 236(3): 540-548, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31670395

RESUMO

Since embryonic heart development is a complex process and acquisition of human embryonic specimens is challenging, the mechanism by which the embryonic conduction system develops remains unclear. Herein, we attempt to gain insights into this developmental process through immunohistochemical staining and 3D reconstructions. Expression analysis of T-box transcription factor 3, cytoskeleton desmin, and nucleoskeleton lamin A protein in human embryos in Carnegie stages 11-20 showed that desmin is preferentially expressed in the myocardium of the central conduction system compared with the peripheral conduction system, and is co-expressed with T-box transcription factor 3 in the central conduction system. Further, lamin A was first expressed in the embryonic ventricular trabeculations, where the terminal ramifications of the peripheral conduction system develop, and extended progressively to all parts of the central conduction system. The uncoupled spatiotemporal distribution pattern of lamin A and desmin indicated that the association of cytoskeleton desmin and nucleoskeleton lamin A may be a late event in human embryonic heart development. Compared with model animals, our data provide a direct morphological basis for understanding the arrhythmogenesis caused by mutations in human DES and LMNA genes.

20.
Chem Commun (Camb) ; 56(1): 66-69, 2019 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-31790104

RESUMO

A highly stable hydrogen-bonded organic framework, HOF-14, has been successfully constructed and structurally characterized. It possesses a permanent three dimensional (3D) porous structure. The activated HOF-14 has a high BET surface area of 2573 m2 g-1 and a record large pore volume of 1.36 cm3 g-1 among HOF materials. In addition, HOF-14 also exhibits high chemical and thermal stability and is capable of highly selective separation of light hydrocarbons under ambient conditions.

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