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1.
Plant Biotechnol J ; 2024 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-38923257

RESUMO

Oil-Camellia (Camellia oleifera), belonging to the Theaceae family Camellia, is an important woody edible oil tree species. The Camellia oil in its mature seed kernels, mainly consists of more than 90% unsaturated fatty acids, tea polyphenols, flavonoids, squalene and other active substances, which is one of the best quality edible vegetable oils in the world. However, genetic research and molecular breeding on oil-Camellia are challenging due to its complex genetic background. Here, we successfully report a chromosome-scale genome assembly for a hexaploid oil-Camellia cultivar Changlin40. This assembly contains 8.80 Gb genomic sequences with scaffold N50 of 180.0 Mb and 45 pseudochromosomes comprising 15 homologous groups with three members each, which contain 135 868 genes with an average length of 3936 bp. Referring to the diploid genome, intragenomic and intergenomic comparisons of synteny indicate homologous chromosomal similarity and changes. Moreover, comparative and evolutionary analyses reveal three rounds of whole-genome duplication (WGD) events, as well as the possible diversification of hexaploid Changlin40 with diploid occurred approximately 9.06 million years ago (MYA). Furthermore, through the combination of genomics, transcriptomics and metabolomics approaches, a complex regulatory network was constructed and allows to identify potential key structural genes (SAD, FAD2 and FAD3) and transcription factors (AP2 and C2H2) that regulate the metabolism of Camellia oil, especially for unsaturated fatty acids biosynthesis. Overall, the genomic resource generated from this study has great potential to accelerate the research for the molecular biology and genetic improvement of hexaploid oil-Camellia, as well as to understand polyploid genome evolution.

2.
Phys Rev Lett ; 133(7): 076301, 2024 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-39213552

RESUMO

Understanding the interplay of interaction and disorder in quantum transport poses long-standing scientific challenges for theory and experiment. While highly controlled ultracold atomic platforms combining atomic interactions with spatially disordered lattices have led to remarkable advances, the extension of such controlled studies to phenomena in high-dimensional disordered systems, such as the three-dimensional Anderson metal-insulator transition has been limited. Kicked quantum gases provide an alternate experimental platform that captures the Anderson model in momentum space and features dynamical localization as the analog of Anderson localization. Here, we utilize a momentum space lattice platform using quasiperiodically kicked ultracold atomic gases to experimentally investigate interaction effects on the three-dimensional dynamical Anderson metal-insulator transition. We observe interaction-driven subdiffusion and a divergence of delocalization onset time on approaching the phase boundary. Mean-field numerical simulations show qualitative agreement with experimental observations, but with significant quantitative deviations.

3.
Environ Sci Technol ; 58(31): 13687-13696, 2024 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-39067068

RESUMO

Bisphenols, parabens, and triclosan (TCS) are common endocrine disrupters used in various consumer products. These chemicals have been shown to cross the placental barrier and affect intrauterine development of fetuses. In this study, we quantified serum levels of six bisphenols, five parabens, and TCS in 483 pregnant women from southern China. Quantile-based g-computation showed that combined exposure to bisphenols, parabens, and TCS was significantly (p < 0.05) and negatively associated with birth weight (ß = -39.9, 95% CI: -73.8, -6.1), birth length (ß = -0.19, 95% CI: -0.34, -0.04), head circumference (ß = -0.13, 95% CI: -0.24, -0.02), and thoracic circumference (ß = -0.16, 95% CI: -0.29, -0.04). An inverse correlation was also identified between mixture exposure and gestational age (ß = -0.12, 95% CI: -0.24, -0.01). Bisphenol A (BPA), bisphenol Z (BPZ), bisphenol AP (BPAP), propylparaben (PrP), and TCS served as the dominant contributors to the overall effect. In subgroup analyses, male newborns were more susceptible to mixture exposure than females, whereas the exposure-outcome link was prominent among pregnant women in the first and second trimesters. More evidence is warranted to elucidate the impacts of exposure to mixtures on birth outcomes, as well as the underlying mechanisms.


Assuntos
Peso ao Nascer , Idade Gestacional , Parabenos , Fenóis , Triclosan , Humanos , Feminino , Gravidez , Peso ao Nascer/efeitos dos fármacos , Adulto , Masculino , Recém-Nascido , Exposição Materna , Disruptores Endócrinos , Compostos Benzidrílicos , China , Trimestres da Gravidez
4.
Environ Res ; : 119835, 2024 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-39181298

RESUMO

Dyslipidemia is a prevalent metabolic disorder in older adults and has negative effects on cardiovascular health. However, the combined effect of paraben, bisphenol A (BPA), and triclosan (TCS) exposure on dyslipidemia and the underlying mechanisms remain unclear. This cross-sectional study recruited 486 individuals ≥60 years in Shenzhen, China. Morning spot urine samples were collected and analyzed for four parabens, BPA, TCS, and 8-hydroxy-2'-deoxyguanosine (8-OHdG), a typical biomarker for oxidative stress, using mass spectrometry. Blood samples were tested for lipid levels using an automated biochemical analyzer. Quantile-based g-computation (QGC) was used to assess the combined effects of exposures on dyslipidemia. Mediation analysis was applied to investigate the mediating role of 8-OHdG between exposure and dyslipidemia. QGC showed that co-exposure to parabens, BPA, and TCS was positively linked with hypercholesterolemia (OR: 1.17, 95%CI: 1.10-1.24, P<0.001) and hyper-LDL-cholesterolemia (OR: 1.35, 95%CI: 1.05-1.75, P=0.019). Methylparaben (MeP), n-propyl paraben (PrP), and butylparaben (BtP) were the major contributors. 8-OHdG mediated 6.5% and 13.0% of the overall effect of the examined chemicals on hypercholesterolemia and hyper-LDL-cholesterolemia, respectively (all P<0.05). Our study indicated that co-exposure to parabens, BPA, and TCS is associated with dyslipidemia and oxidative stress partially mediate the association. Future research is needed to explore additional mechanisms underlying these relationships.

5.
Int J Mol Sci ; 25(16)2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-39201575

RESUMO

Clinical investigations have highlighted disruptions in bone metabolic processes and abnormal fluctuations in serum indicator levels during the onset of leg disease (LD) in broilers. However, the presence of a genetic causal relationship for this association remains undetermined. Therefore, the aim of this study is to discern the risk factors underlying LD development using 1235 sequenced white-feathered broilers. We employed Mendelian randomization (MR) analysis to assess the associations of bone strength (BS), bone mineral density (BMD), tibial bone weight (TBW), tibial bone length (TBL), tibial bone diameter (TBD), bone ash (BA), ash calcium (Ash Ca), ash phosphorus (Ash P), serum calcium (Ca), serum phosphorus (P), serum alkaline phosphatase (ALP), and serum osteoprotegerin (OPG) with the incidence of LD. Compelling evidence underscores a causal link between the risk of developing LD and decreased BMD (odds ratio (OR) = 0.998; 95% CI: 0.983, 0.993; P < 0.001) and narrower TBD (OR = 0.985, 95% CI: 0.975, 0.994, P = 0.002). Additionally, serum OPG concentrations (OR: 0.995, 95% CI: 0.992, 0.999, P = 0.008) were associated with BMD (OR = 0.0078, 95% CI = 0.0043 to 0.0140, P < 0.001), indicating a robust genetic relationship between ALP concentrations (OR: 0.988, 95% CI: 0.984, 0.993, P < 0.001) and TBD (OR = 0.0046, 95% CI = 0.0026, 0.0083, P < 0.001). Moreover, elevated serum Ca (OR: 0.564, 95% CI: 0.487, 0.655, P < 0.001) and P (OR: 0.614, 95% CI: 0.539, 0.699, P < 0.001) levels were associated with a narrower TBD. Elevated serum levels of Ca, P, ALP, and OPG contribute to disturbances in bone metabolism, while decreased BMD and narrower TBD are associated with a greater risk of developing LD in broilers. This discovery elucidates the metabolic risk factors for LD in broilers and could provide information on LDs, such as osteoporosis, in humans.


Assuntos
Densidade Óssea , Galinhas , Análise da Randomização Mendeliana , Animais , Galinhas/genética , Fatores de Risco , Densidade Óssea/genética , Predisposição Genética para Doença , Doenças das Aves Domésticas/genética , Doenças das Aves Domésticas/epidemiologia , Osteoprotegerina/genética , Osteoprotegerina/sangue , Polimorfismo de Nucleotídeo Único
6.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 41(8): 977-981, 2024 Aug 10.
Artigo em Chinês | MEDLINE | ID: mdl-39097283

RESUMO

OBJECTIVE: To explore the correlation between structural chromosomal abnormality and clinical characteristics of a child featuring gonadal dysplasia. METHODS: A 13-year-old child who was admitted to Lianyungang Maternal and Child Health Care Hospital on February 7, 2023 for primary amenorrhoea and occasional abdominal pain was selected as the study subject. Clinical data of the child was collected, and peripheral blood samples of the child and her parents were collected. G-banding chromosomal karyotyping and copy number variation sequencing (CNV-seq) were carried out. "Pseudodual centromere isochromosome X" and "psu idic(X)" were used as keywords to search the CNKI, Wanfang and PubMed databases, and the search period was set as from January 1, 2002 to June 1, 2023. Relevant literature on the structural abnormality of X chromosome was searched and analyzed retrospectively. RESULTS: The child has a height of 153 cm and weighed 45 kg. She has no obvious facial dysmorphism. Laboratory tests showed that she had higher FSH and luteinizing hormone, and lower E2. Ultrasonography showed that she had small ovaries and rudimentary uterus. She was found to have a karyotype of 46,X,psu idic(X)(q21.3)[40]/mos 45,X[3], whilst both of her parents had a normal karyotype. CNV-seq showed that she had a 63.27 Mb deletion in Xq21.32q28 and a 91.59 Mb duplication in Xp22.33q21.32 (mosaicism rate = 74%). A total of 11 relevant literature were retrieved. Clinical phenotypes of patients with similar structural chromosomal abnormalities were diverse, which was closely related to the mosaicism rate of the 45,X karyotype and the location of the breaking point. CONCLUSION: 46,X,psu idic(X)(q21.3)/45,X probably underlay the dysplasia of uterus and ovary and sex hormone abnormalities in this child, while her height was spared. Deletion of Xq21.32q28 is a key factor leading to Turner syndrome-like phenotype such as rudimentary uterus and ovarian dysplasia.


Assuntos
Cariotipagem , Humanos , Feminino , Adolescente , Cromossomos Humanos X/genética , Aberrações dos Cromossomos Sexuais , Variações do Número de Cópias de DNA , Bandeamento Cromossômico , Testes Genéticos
7.
J Obstet Gynaecol Res ; 49(12): 2825-2835, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37806662

RESUMO

AIM: To investigate the detectability of noninvasive prenatal screening (NIPS) with conventional sequencing depth to detect fetal copy number variants. METHODS: We performed a retrospective study in a total of 19 144 pregnant women. Their cell-free plasma DNA were assessed for trisomy 21, trisomy 18, trisomy 13, sex chromosome aneuploidies, and genome-wide copy number variants by NIPS at conventional sequencing depth. RESULTS: Three hundred seventy-four cases (2.0%, 374/19 144) with abnormal results were detected, which including 84 cases (0.4%, 84/19 144) with high risk of trisomy 21, 18, and 13, 90 cases (0.5%, 90/19 144) with high risk of sex chromosome abnormalities (SCA), and 44 cases (0.2%, 44/19 144) with high risk of other chromosome aneuploidies. One hundred fifty-six cases (0.8%, 156/19 144) with high risk of copy number variations (CNVs) were also detected. In following prenatal diagnosis, composite positive predictive value (PPV) of trisomy 21, 18, and 13 was 69.6% (48/69). The PPV of SCAs was 37.3% (19/51). And the PPVs for CNVs was detected as 51.0% (<5 Mb), 71.4% (5 Mb ≤ CNV ≤10 Mb), 56.5% (>10 Mb). Finally, a follow-up about the pregnancy outcomes were conducted for all available cases. CONCLUSIONS: NIPS yielded high PPVs for trisomy 21, 18, and 13 aneuploidies and moderate PPVs for SCAs and CNVs. The screening effectiveness was closely related to the size of CNV fragments. Larger CNVs, especially larger than 5 Mb, could be detected more accurately by NIPS in our analytic technique. Meanwhile, diagnostic confirmation by microarray analysis was highly recommended.


Assuntos
Transtornos Cromossômicos , Síndrome de Down , Teste Pré-Natal não Invasivo , Gravidez , Feminino , Humanos , Transtornos Cromossômicos/diagnóstico , Transtornos Cromossômicos/genética , Síndrome de Down/diagnóstico , Síndrome de Down/genética , Estudos Retrospectivos , Variações do Número de Cópias de DNA , Gestantes , Diagnóstico Pré-Natal , Aneuploidia , Aberrações dos Cromossomos Sexuais
8.
J Assist Reprod Genet ; 40(9): 2233-2240, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37501006

RESUMO

PURPOSE: To report a rare type of Pallister-Killian syndrome (PKS) diagnosed prenatally by the utility of non-invasive prenatal testing (NIPT). METHODS: NIPT was performed in the first trimester. Conventional karyotyping and chromosomal microarray analysis (CMA) were performed on the amniotic samples in the second trimester. Copy number variation sequencing (CNV-seq) was used for the validation of fetal skin and the placental tissue after pregnancy termination. RESULTS: NIPT results showed increased signal from chromosome 12p. Subsequent prenatal diagnostic testing by karyotype revealed 47, XY, +i (12p), and CMA displayed four copies of 12p: 12p13.33-12p11.1(173786_34835641) × 4. The CNV-seq results of the fetal skin and the fetal side of placenta showed four copies of 12p13.33-p11 and an estimated chimeric duplication of 34.08 Mb (chimerism ratio: 10%) in 12 p13.33-p11, respectively. However, no abnormality was detected by CNV-seq at the maternal side of placenta. CONCLUSIONS: Our findings suggest that a positive signal from chromosome 12p on NIPT should raise suspicion for PKS. With the wide application of NIPT, the true positive of incidental finding is expected to increase.


Assuntos
Transtornos Cromossômicos , Teste Pré-Natal não Invasivo , Gravidez , Feminino , Humanos , Tetrassomia , Variações do Número de Cópias de DNA/genética , Placenta , Diagnóstico Pré-Natal , Transtornos Cromossômicos/diagnóstico , Transtornos Cromossômicos/genética , Cromossomos Humanos Par 12/genética
9.
Plant Dis ; 2023 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-37079018

RESUMO

Tea (Camellia sinensis), which originated in southwest of China 60 - 70 million years ago, is widely consumed as a beverage for its potential enhancing effect on human health with rich polyphenol content (Pan et al. 2022). From October to December in 2021, a disease with symptoms similar to leaf spot affected the quality and yield of tea Puer (102°73 'E, 25°07' N), Yunnan province, China. Based on the survey, leaf spot symptoms were observed on approximately 60% of tea plants in a 5,700 m2 field. The symptoms initially appeared as shrinking, yellowing, and later became circular or irregular brown spots. To isolate the pathogen, 10 symptomatic leaves were collected from 10 trees, and portions of the diseased tissue (0.5×0.5 cm) were cut at the junction of infected and healthy tissues. After surface sterilization (0.5 min with 75% ethanol and 2 min with 3% NaOCl, washed three times with sterilized distilled water), the disinfected pieces were dried and plated onto potato dextrose agar (PDA) and incubated at 25°C in the dark for 5 days. Four single-spore isolates, FH-1, FH-5, FH-6 and FH-7, were obtained, these isolates were identical in morphology and in the sequences of internal transcribed spacer region [ITS] and translation elongation factor 1-alpha [TEF] genes. Therefore, the representative isolate FH-5 was used for further study. Fungal colonies were white or light yellow on PDA after 7 days incubated at 28ºC. Conidia were hyaline, round or oval, aseptate, occur singly or in clusters on hyphae or conidia stalks, and measured as 2.94 ± 1.79 × 1.82 ± 0.2 µm (n = 50). Primary conidiophores is Verticillium-like (Fig1.K,L), which generally formed first, 1-3-level verticillate, mostly with divergent branches and phialides, and measured as 16.67 ± 4.39 µm (n = 50). Secondary conidiophores is penicillate (Fig1.I,J), which generally appearing after one week, sometimes even more often branched, and with a length of 16.02 ± 3.83 µm (n = 50). The morphological features were consistent with the descriptions of Clonostachys rosea Schroers H.J. (Schroers et al. 1999). The pathogen was confirmed to be C. rosea by amplification and sequencing of the internal transcribed spacer region (ITS) and translation elongation factor 1-alpha (TEF) genes using primers ITS1/ITS4 and EF1-728F/EF1-986R, respectively (Fu Rongtao 2019). The sequences of PCR products were deposited in GenBank with accession numbers ON332533 (ITS) and OP080234 (TEF). BLAST searches of the obtained sequences revealed 99.22% (510/514 nucleotides) and 98.37% (241/245 nucleotides) homology with those of C. rosea HQ-9-1 form GenBank (MZ433177 and MZ451399, respectively). Phylogenetic analysis (MEGA 7.0) using the maximum likelihood method placed the isolate FH-5 in a well-supported cluster with C. rosea. The pathogenicity of FH-5 was tested through a pot assay. Ten healthy tea plants were scratched with a sterilized needle on the leaves. Plants were inoculated by spraying a spore suspension (105 spores·mL-1) of FH-5 onto leaves until runoff, and the control leaves sprayed with sterile water. Inoculated plants were put in an artificial climate box at 25℃, 70% relative humidity. The pathogenicity test was replicated three times. Symptoms developed on all inoculated leaves but not on the control leaves. Lesions around the wound edge became pale yellow, and brown spots were first observed at 72 h after inoculation, and typical lesions similar to those observed on field plants appeared after two weeks. The same fungus was reisolated and identified based on the morphological characterization and molecular analyses (ITS and TEF) from the infected leaves but not from the noninoculated leaves. In addition, C. rosea has also been reported to cause diseases to broad bean (N. Afshari et al. 2017 ), garlic (Diaz et al. 2022), beet (Haque M.E et al. 2020) and other plants. To our knowledge, this is the first report of leaf spot on tea caused by C. rosea in China. This study provides valuable information for the identification and control of the leaf spot on tea.

10.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 40(4): 490-494, 2023 Apr 10.
Artigo em Chinês | MEDLINE | ID: mdl-36972948

RESUMO

OBJECTIVE: To explore the genetic basis for a fetus with severe heart defect and mosaic trisomy 12, and the correlation between chromosomal abnormalities and clinical manifestations and pregnancy outcome. METHODS: A 33-year-old pregnant woman who presented at Lianyungang Maternal and Child Health Care Hospital on May 17, 2021 due to abnormal fetal heart development revealed by ultrasonography was selected as the study subject. Clinical data of the fetus were collected. Amniotic fluid sample of the pregnant women was collected and subjected to G-banded chromosomal karyotyping and chromosomal microarray analysis (CMA). The CNKI, WanFang and PubMed databases were searched with key words, with the retrieval period set as from June 1, 1992 to June 1, 2022. RESULTS: For the 33-year-old pregnant woman, ultrasonography at 22+6 gestational weeks had revealed abnormal fetal heart development and ectopic pulmonary vein drainage. G-banded karyotyping showed that the fetus has a karyotype of mos 47,XX,+12[1]/46,XX[73], with the mosaicism rate being 1.35%. CMA results suggested that about 18% of fetal chromosome 12 was trisomic. A newborn was delivered at 39 weeks of gestation. Follow-up confirmed severe congenital heart disease, small head circumference, low-set ears and auricular deformity. The infant had died 3 months later. The database search has retrieved 9 reports. Literature review suggested that the liveborn infants with mosaic trisomy 12 had diverse clinical manifestations depending on the affected organs, which had included congenital heart disease and/or other organs and facial dysmorphisms, resulting in adverse pregnancy outcomes. CONCLUSION: Trisomy 12 mosaicism is an important factor for severe heart defects. The results of ultrasound examination have important value for evaluating the prognosis of the affected fetuses.


Assuntos
Transtornos Cromossômicos , Cardiopatias Congênitas , Recém-Nascido , Criança , Gravidez , Feminino , Humanos , Adulto , Trissomia/genética , Amniocentese/métodos , Mosaicismo , Feto , Cardiopatias Congênitas/genética
11.
Angew Chem Int Ed Engl ; 62(51): e202311027, 2023 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-37749060

RESUMO

The exponential proliferation of conformers makes it impossible to examine the entire population in most systems. Controlling conformational ensembles is thus pivotal in many areas of chemistry. Rh2 (esp)2 , a dicarboxylate-derived paddlewheel rhodium complex, is one of the most effective catalysts for nitrene chemistry. Its enormous success has led to preparing many analogous complexes. However, there has been little consideration for the conformational dynamics of the parent catalyst. Herein, we report a new ligand modification principle that prevents conformer interconversion. The resulting complex comprises two isolable conformers, whose structures have been determined by X-ray diffraction. Combined experimental and computational data has revealed similarities and dissimilarities between the conformationally confined and parent complexes. Three model cases have demonstrated the utility of conformational fixation in the development of stereoselective catalysts for nitrene transfer reactions. The design principle described in this study can be combined with other established modification strategies, serving as a springboard for further advancement of the chemistry of paddlewheel metal complexes.

12.
J Microsc ; 285(2): 112-116, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34866187

RESUMO

An optical waveguide cantilever system with a tip is introduced as the displacement detection system of chip-based atomic force microscopy (AFM) system. A chip-based AFM on optical waveguide is demonstrated with sensitivity of up to 4.0 × 10-2 nm-1 , which is mainly constructed by a 210 nm thick optical waveguide cantilever with a nano-tip. The nano-tip is a height of 1.2 µm and diameter of 140 nm. This integrated on-chip system provides a displacement range of approximately ±0.4 µm, which makes it possible for the device to be used for AFM imaging and pays the way for further performance improvement.

13.
Angew Chem Int Ed Engl ; 61(47): e202212421, 2022 11 21.
Artigo em Inglês | MEDLINE | ID: mdl-36202757

RESUMO

Pyrrolidines are significant N-heterocycles in medicinal chemistry and are among the top ten ring systems found in drug molecules. While simple derivatives are commercially available, densely decorated derivatives with precise stereochemical arrangements remain difficult to obtain. Methods for synthesizing multisubstituted pyrrolidines with nonadjacent stereocenters are particularly scarce. To bridge this gap, we report the stereoselective synthesis of remotely decorated, trisubstituted ß-prolines via Rh-catalyzed C-H amination. The transformation proceeds well in the presence of various functionalities with exclusive anti-selectivity. Carboxylic acids in the products serve as gateways for diverse downstream transformations. Furthermore, the combined experimental and computational study sheds lights on the origin of high diastereoselectivity.


Assuntos
Ródio , Ródio/química , Pirrolidinas , Catálise , Iminas
14.
J Am Chem Soc ; 143(1): 481-487, 2021 01 13.
Artigo em Inglês | MEDLINE | ID: mdl-33356206

RESUMO

Polysulfide anions are endowed with unique redox properties, attracting considerable attentions for their applications in alkali metals-sulfur batteries. However, the employment of these anionic species in redox catalysis for small molecule synthesis remains underdeveloped due to their moderate-poor electrochemical potential in the ground state, whereas some of them are characterized by photoabsorptions in visible spectral regions. Herein, we disclose the use of polysulfide anions as visible light photoredox catalysts for aryl cross-coupling reactions. The reaction design enables single-electron reduction of aryl halides upon the photoexcitation of tetrasulfide dianions (S42-). The resulting aryl radicals are engaged in (hetero)biaryl cross-coupling, borylation, and hydrogenation in a redox catalytic regime involving S4• -/S42- and S3• -/S32- redox couples.

15.
J Am Chem Soc ; 143(33): 13266-13273, 2021 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-34428911

RESUMO

Since the seminal work of Zhang in 2016, donor-acceptor cyanoarene-based fluorophores, such as 1,2,3,5-tetrakis(carbazol-9-yl)-4,6-dicyanobenzene (4CzIPN), have been widely applied in photoredox catalysis and used as excellent metal-free alternatives to noble metal Ir- and Ru-based photocatalysts. However, all the reported photoredox reactions involving this chromophore family are based on harnessing the energy from a single visible light photon, with a limited range of redox potentials from -1.92 to +1.79 V vs SCE. Here, we document the unprecedented discovery that this family of fluorophores can undergo consecutive photoinduced electron transfer (ConPET) to achieve very high reduction potentials. One of the newly synthesized catalysts, 2,4,5-tri(9H-carbazol-9-yl)-6-(ethyl(phenyl)amino)isophthalonitrile (3CzEPAIPN), possesses a long-lived (12.95 ns) excited radical anion form, 3CzEPAIPN•-*, which can be used to activate reductively recalcitrant aryl chlorides (Ered ≈ -1.9 to -2.9 V vs SCE) under mild conditions. The resultant aryl radicals can be engaged in synthetically valuable aromatic C-B, C-P, and C-C bond formation to furnish arylboronates, arylphosphonium salts, arylphosphonates, and spirocyclic cyclohexadienes.

16.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 38(2): 101-107, 2021 Feb 10.
Artigo em Chinês | MEDLINE | ID: mdl-33565058

RESUMO

OBJECTIVE: To assess the value of chromosomal microarray analysis (CMA) for the detection of fetal anomalies among pregnant women with advanced age. METHODS: CMA results of 562 cases, in addition with the outcome of pregnancy and neonatal follow-up were reviewed. RESULTS: Among the 562 amniotic fluid samples, 73 cases (12.99%) of fetal chromosomal abnormalities were detected, which included 21 cases (3.73%) of chromosomal aneuploidies and 52 cases (9.25%) of copy number variations (CNVs). The latters included 27 cases of pathological CNVs (4.80%), 4 cases of possible pathogenic CNVs (0.71%) and 42 cases of variants with unknown clinical significance (7.47%). Compared with those under 35, the detection rate of fetal chromosomal aneuploidies for women with advanced age was higher under the indications of voluntary test, abnormal ultrasonic structures, abnormal ultrasonic soft index and risks indicated by non-invasive prenatal testing (NIPT). No significant difference was found in the detection rate of CNVs between those ≥35 and <35 and between those with age factor only and with additional indications (P> 0.05). 552 cases (98.22%) of pregnant women have completed the followed up. Among 31 women with pathological and possible pathogenic fetal CNVs detected by CMA, 25 had terminated the pregnancy, 6 (19.35%) have delivered without obvious abnormality. 41 pregnant women with fetal CNVs of unknown clinical significance have completed the follow up, among whom 3 had terminated the pregnancy, 1 newborn was found with malformation after birth, which yielded an abnormal pregnancy rate of 9.76%. 480 pregnant women with negative CMA results have completed the follow up, among whom 5 (1.04%) had abnormal pregnancy or delivered a child with birth defect. CONCLUSION: There is a certain difference between the outcome of pregnancy predicted by CMA testing and the actual outcome. The pregnancies with fetal CNVs with unknown clinical significance detected by CMA have a high adverse rate, which should attract clinical attention. CMA testing should be recommended for pregnant women with advanced age regardless of whether they have other symptoms. CMA combined with other detection methods is the trend for prenatal diagnosis.


Assuntos
Aberrações Cromossômicas , Idade Materna , Análise de Sequência com Séries de Oligonucleotídeos , Diagnóstico Pré-Natal , Aneuploidia , Variações do Número de Cópias de DNA , Feminino , Humanos , Recém-Nascido , Gravidez
17.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 37(2): 190-194, 2020 Feb 10.
Artigo em Chinês | MEDLINE | ID: mdl-32034753

RESUMO

OBJECTIVE: To explore the genetic basis for a child with autism spectrum disorder (ASD) and congenital heart disease. METHODS: G-banded chromosomal karyotyping was carried out for the patient and his parents. The child was also subjected to whole exome sequencing (WES) and low-coverage massively parallel copy number variation sequencing (CNV-seq). The result was validated by chromosomal microarray analysis (CMA). RESULTS: The karyotype of the patient and his parents were normal. No significant genetic variation was found by WES. However, CNV-seq has discovered a 47, XY, +21 [10%]/46,XY [90%] mosaicism in the patient. The result was confirmed by CMA. CONCLUSION: In addition to Down syndrome, low proportion mosaic trisomy 21 is also associated with ASD. WES and CNV-seq can enable accurate diagnosis for patient with unexplained ASD.


Assuntos
Transtorno do Espectro Autista , Mosaicismo , Trissomia , Dissomia Uniparental , Criança , Cromossomos Humanos Par 21 , Variações do Número de Cópias de DNA , Humanos
18.
Sensors (Basel) ; 19(17)2019 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-31450708

RESUMO

It is difficult for multichannel maneuvering synthetic aperture radar (SAR) to achieve ground moving target 2D velocity estimation and refocusing. In this paper, a novel method based on back projection (BP) and velocity SAR (VSAR) is proposed to cope with the issues. First, the static scene is reconstructed by BP to solve the imaging problem of multichannel maneuvering SAR. Then, the static clutter is suppressed, and the range velocity is estimated via VSAR processing. As for azimuth velocity estimation and refocusing, a velocity search method based on velocity-aided BP (VA-BP) and VSAR is proposed to accomplish them. First, each azimuth velocity in the search and the estimated range velocity are used to image the moving target in a small-sized subimage space by VA-BP, i.e., matching the range history and the Doppler phase of the moving target in the image processing. Then, multiple sets of multichannel SAR subimages corresponding to different azimuth velocities are generated, and the clutter of each set of multichannel SAR subimages is also suppressed by VSAR processing. After that, the azimuth velocity is estimated by searching the clutter-suppressed subimage of the first spatial receiving channel in each set of multichannel SAR subimages with the best refocusing quality measured by the minimum entropy. Simulation results show the proposed method can reach high accuracy in moving target 2D velocity estimation and refocusing with the absolute error of 2D velocity estimation smaller than 0.1 m/s.

19.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 36(2): 108-111, 2019 Feb 10.
Artigo em Chinês | MEDLINE | ID: mdl-30703224

RESUMO

OBJECTIVE: To determine the frequencies of deafness gene mutations among patients with non-syndromic hearing loss (NSHL) from northern Jiangsu province. METHODS: A total of 117 patients with NSHL were enrolled. The coding region of GJB2 gene, IVS7-2A>G and 2168A>G mutations of SLC26A4 gene, and 1555A>G and 1494C>T mutations of mitochondrial DNA 12S rRNA were subjected to Sanger sequencing. Patients in whom no mutation was detected were further tested by targeted gene capture and high-throughput sequencing. RESULTS: Among the 117 patients, 86 (73.50%) were found to carry mutations. GJB2 gene mutations were found in 61 patients (52.14%), including 22 (18.80%) with homozygous mutations and 39 (33.33%) with heterozygous mutations. SLC26A4 gene mutations were found in 19 patients (16.24%), including 4 (3.42%) with homozygous mutations and 15 with heterozygous mutations (14.53%). Mitochondrial 12S rRNA gene mutation was found in 6 patients (5.13%). Targeted gene capture and high-throughput sequencing of 8 patients identified 4 further cases, including 1 with RDX gene 129_130del and 76_79del compound heterozygous mutations, 1 with OTOF gene 1274G>C homozygous mutation, 1 with SLC26A4 gene 919-2A>G and IVS16-6G>A compound heterozygous mutation, and 1 with SLC26A4 gene 919-2A>G and A1673T compound heterozygous mutation. CONCLUSION: The frequency of mutation among patients with NSHL from north Jiangsu was 73.50%, and GJB2 gene was most commonly mutated.


Assuntos
Perda Auditiva , Mutação , China , Conexinas , Análise Mutacional de DNA , DNA Mitocondrial , Perda Auditiva/genética , Humanos , Proteínas de Membrana , Transportadores de Sulfato
20.
J Am Chem Soc ; 140(11): 4157-4163, 2018 03 21.
Artigo em Inglês | MEDLINE | ID: mdl-29498516

RESUMO

Alkanes, the main constituents of petroleum, are attractive feedstocks for producing value-added chemicals. Linear aldehydes and amines are two of the most important building blocks in the chemical industry. To date, there have been no effective methods for directly converting n-alkanes to linear aldehydes and linear amines. Here, we report a molecular dual-catalyst system for production of linear aldehydes via regioselective carbonylation of n-alkanes. The system is comprised of a pincer iridium catalyst for transfer-dehydrogenation of the alkane using t-butylethylene or ethylene as a hydrogen acceptor working sequentially with a rhodium catalyst for olefin isomerization-hydroformylation with syngas. The system exhibits high regioselectivity for linear aldehydes and gives high catalytic turnover numbers when using ethylene as the acceptor. In addition, the direct conversion of light alkanes, n-pentane and n-hexane, to siloxy-terminated alkyl aldehydes through a sequence of Ir/Fe-catalyzed alkane silylation and Ir/Rh-catalyzed alkane carbonylation, is described. Finally, the Ir/Rh dual-catalyst strategy has been successfully applied to regioselective alkane aminomethylation to form linear alkyl amines.

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