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1.
BMC Cardiovasc Disord ; 23(1): 270, 2023 05 23.
Artigo em Inglês | MEDLINE | ID: mdl-37221473

RESUMO

BACKGROUND: Hypertension affects 31.1% of adults worldwide, with higher prevalence of great than 60% in elderly. Advanced hypertension stage was associated with the higher risk of mortality. However, little is known about the age-specific association of stage of hypertension at diagnosis on cardiovascular mortality or all-cause mortality. Therefore, we aim to explore this age-specific association among the hypertensive elderly through stratified and interaction analyses. METHODS: This cohort study included 125,978 elderly hypertensive patients aged 60+ years from Shanghai of China. Cox regression was used to estimate the independent and joint effect of hypertension stage and age at diagnosis on cardiovascular and all-cause mortality. Interactions were evaluated both additively and multiplicatively. Multiplicative interaction was examined by the Wald test of the interaction term. Additive interaction was assessed by relative excess risk due to interaction (RERI). All analyses were performed stratified by sex. RESULTS: 28,250 patients died during the follow-up up to 8.85 years, and 13,164 died of cardiovascular events. Older age and advanced hypertension stage were risk factors of cardiovascular mortality and all-cause mortality. Besides, smoking, rarely exercise, BMI < 18.5 and diabetes were also the risk factors. When we compared stage 3 hypertension with stage 1 hypertension, hazard ratios (95% confidence interval) of cardiovascular mortality and all-cause mortality were 1.56(1.41-1.72) and 1.29(1.21-1.37) for males aged 60-69 years, 1.25(1.14-1.36) and 1.13(1.06-1.20) for males aged 70-85 years, 1.48(1.32-1.67) and 1.29(1.19-1.40) for females aged 60-69 years, and 1.19(1.10-1.29) and 1.08(1.01-1.15) for females aged 70-85 years, respectively. Negative multiplicative interaction and positive additive interaction between age at diagnosis and stage of hypertension at diagnosis on cardiovascular mortality were observed in males (HR: 0.81, 95% CI: 0.71-0.93 RERI: 0.59, 95% CI: 0.09-1.07) and females (HR: 0.81, 95% CI: 0.70-0.93 RERI: 0.66, 95% CI: 0.10-1.23). CONCLUSIONS: Diagnosed with stage 3 hypertension was associated with higher risks of cardiovascular mortality and all-cause mortality, which were stronger among patients with age at diagnosis of 60-69 years compared with those with age at diagnosis of 70-85 years. Therefore, for the younger part of the elderly, the Department of Health should pay more attention to treating patients with stage 3 hypertension.


Assuntos
Sistema Cardiovascular , Hipertensão , Adulto , Idoso , Feminino , Masculino , Humanos , Estudos de Coortes , China , Fatores Etários
2.
J Cell Sci ; 133(6)2020 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-32041901

RESUMO

To investigate the mechanisms underlying initiation of the sexual cell cycle in eukaryotes, we have focused on cyclins and cyclin-dependent kinases (CDKs) in the well-studied model ciliate, Tetrahymena thermophila We identified two genes, CDK19 and CYC9, which are highly co-expressed with the mating-associated factors MTA, MTB and HAP2. Both CDK19 and CYC9 were found to be essential for mating in T. thermophila Subcellular localization experiments suggested that these proteins are located at the oral area, including the conjugation junction area, and that CDK19 or CYC9 knockout prevents mating. We found that CDK19 and CYC9 form a complex, and also identified several additional subunits, which may have regulatory or constitutive functions. RNA sequencing analyses and cytological experiments showed that mating is abnormal in both ΔCDK19 and ΔCYC9, mainly at the entry to the co-stimulation stage. These results indicate that the CDK19-CYC9 complex initiates the sexual cell cycle in T. thermophila.


Assuntos
Divisão Celular , Quinases Ciclina-Dependentes , Tetrahymena thermophila , Tetrahymena , Quinases Ciclina-Dependentes/genética , Ciclinas/genética , Células Germinativas , Tetrahymena thermophila/genética
3.
J Am Chem Soc ; 137(12): 4267-73, 2015 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-25767939

RESUMO

An unprecedented asymmetric catalytic tandem aminolysis/aza-Michael addition reaction of spirocyclic para-dienoneimides has been designed and developed through organocatalytic enantioselective desymmetrization. A unified strategy based on this key tandem methodology has been divergently explored for the asymmetric total synthesis of two natural Apocynaceae alkaloids, (+)-deethylibophyllidine and (+)-limaspermidine. The present studies not only enrich the tandem reaction design concerning the asymmetric catalytic assembly of a chiral all-carbon quaternary stereocenter contained in the densely functionalized hydrocarbazole synthons but also manifest the potential for the application of the asymmetric catalysis based on the para-dienone chemistry in asymmetric synthesis of natural products.


Assuntos
Apocynaceae/química , Produtos Biológicos/síntese química , Alcaloides Indólicos/síntese química , Produtos Biológicos/química , Carbazóis/síntese química , Carbazóis/química , Catálise , Alcaloides Indólicos/química , Modelos Moleculares , Estereoisomerismo
4.
Biol Pharm Bull ; 37(3): 466-74, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24351575

RESUMO

To study the effect of organic Se on spatial learning and memory deficits induced by Pb exposure at different developmental stages, and its relationship with alterations of synaptic structural plasticity, postnatal rat pups were randomly divided into five groups: Control; Pb (Weaned pups were exposed to Pb at postnatal day (PND) 21-42); Pb-Se (Weaned pups were exposed to Se at PND 43-63 after Pb exposure); maternal Pb (mPb) (Parents were exposed to Pb from 3 weeks before mating to the weaning of pups); mPb-Se (Parents were exposed to Pb and weaned pups were exposed to Se at PND 43-63). The spatial learning and memory of rat pups was measured by Morris water maze (MWM) on PND 63. We found that rat pups in Pb-Se group performed significantly better than those in Pb group (p<0.05). However, there was no significant difference in the ability of spatial learning and memory between the groups of mPb and mPb-Se (p>0.05). We also found that, before MWM, the numbers of neurons and synapses significantly decreased in mPb group, but not in Pb group. After MWM, the number of synapses, the thickness of postsynaptic density (PSD), the length of synaptic active zone and the synaptic curvature increased significantly in Pb-Se and mPb-Se group; while the width of synaptic cleft decreased significantly (p<0.05), compared to Pb group and mPb group, respectively. However, the number of synapses in mPb-Se group was still significantly lower than that in the control group (p<0.05). Our data demonstrated that organic Se had protective effects on the impairments of spatial learning and memory as well as synaptic structural plasticity induced by Pb exposure in rats after weaning, but not by the maternal Pb exposure which reduced the numbers of neurons and synapses in the early neural development.


Assuntos
Encéfalo/efeitos dos fármacos , Chumbo/efeitos adversos , Deficiências da Aprendizagem/prevenção & controle , Transtornos da Memória/prevenção & controle , Plasticidade Neuronal/efeitos dos fármacos , Selênio/uso terapêutico , Sinapses/efeitos dos fármacos , Animais , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico , Encéfalo/crescimento & desenvolvimento , Exposição Ambiental/efeitos adversos , Feminino , Deficiências da Aprendizagem/induzido quimicamente , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Memória/efeitos dos fármacos , Transtornos da Memória/induzido quimicamente , Neurônios/efeitos dos fármacos , Gravidez , Efeitos Tardios da Exposição Pré-Natal/tratamento farmacológico , Ratos , Ratos Wistar , Selênio/farmacologia , Oligoelementos/farmacologia , Oligoelementos/uso terapêutico
5.
Sci Rep ; 14(1): 15667, 2024 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-38977741

RESUMO

The microreactor with two types of immobilized enzymes, exhibiting excellent orthogonal performance, represents an effective approach to counteract the reduced digestion efficiency resulting from the absence of a single enzyme cleavage site, thereby impacting protein identification. In this study, we developed a hydrophilic dual-enzyme microreactor characterized by rapid mass transfer and superior enzymatic activity. Initially, we selected KIT-6 molecular sieve as the carrier for the dual-IMER due to its three-dimensional network pore structure. Modification involved co-deposition of polyethyleneimine (PEI) and acrylamide (AM) as amine donors, along with dopamine to enhance material hydrophilicity. Remaining amino and double bond functional groups facilitated stepwise immobilization of trypsin and Glu-C. Digestion times for bovine serum albumin (BSA) and bovine hemoglobin (BHb) on the dual-IMER were significantly reduced compared to solution-based digestion (1 min vs. 36 h), resulting in improved sequence coverage (91.30% vs. 82.7% for BSA; 90.24% vs. 89.20% for BHb). Additionally, the dual-IMER demonstrated excellent durability, retaining 96.08% relative activity after 29 reuse cycles. Enhanced protein digestion efficiency can be attributed to several factors: (1) KIT-6's large specific surface area, enabling higher enzyme loading capacity; (2) Its three-dimensional network pore structure, facilitating faster mass transfer and substance diffusion; (3) Orthogonality of trypsin and Glu-C enzyme cleavage sites; (4) The spatial effect introduced by the chain structure of PEI and glutaraldehyde's spacing arm, reducing spatial hindrance and enhancing enzyme-substrate interactions; (5) Mild and stable enzyme immobilization. The KIT-6-based dual-IMER offers a promising technical tool for protein digestion, while the PDA/PEI/AM-KIT-6 platform holds potential for immobilizing other proteins or active substances.


Assuntos
Acrilamida , Dopamina , Enzimas Imobilizadas , Polietilenoimina , Soroalbumina Bovina , Tripsina , Polietilenoimina/química , Dopamina/química , Dopamina/metabolismo , Enzimas Imobilizadas/química , Enzimas Imobilizadas/metabolismo , Acrilamida/química , Tripsina/química , Tripsina/metabolismo , Animais , Bovinos , Soroalbumina Bovina/química , Soroalbumina Bovina/metabolismo , Porosidade , Interações Hidrofóbicas e Hidrofílicas , Hemoglobinas/química , Hemoglobinas/metabolismo , Proteólise
6.
Wei Sheng Yan Jiu ; 42(6): 978-81, 986, 2013 Nov.
Artigo em Zh | MEDLINE | ID: mdl-24459913

RESUMO

OBJECTIVE: To study the effect of lead and (or) selenium on learning and memory ability in rats. METHODS: SPF Wistar rats, after weaning, were divided into six groups, control group, Pb group (respectively Pb exposed), Se group (respectively Se added), Pb-Se group (added Se after Pb exposure), Se-Pb group (added Se before Pb exposure) and Pb + Se group (Pb and Se exposed simultaneously). After intervention for six weeks in rats, the spatial learning and memory of each group rats were measured by Morris water maze assay. RESULTS: Rats in Pb group had significantly longer latency, less site crossings, less percentage of time and distance spent in the target quadrant, and bigger first bearing compared with control group (P < 0.05). Rats in Pb and Se joint exposure groups had significantly shorter latency, more site crossings, less percentage of time and distance spent in the target quadrant, and smaller first bearing compared with Pb group (P < 0.05). There were no significant differences in the indexes of spatial learning and memory ability between the groups of lead and selenium joint exposure groups (P > 0.05). CONCLUSION: Lead damaged the ability of learning and memory in rats and organic selenium had protective effects on Pb-induced spatial learning and memory deficits in rats.


Assuntos
Chumbo/toxicidade , Deficiências da Aprendizagem/prevenção & controle , Aprendizagem/efeitos dos fármacos , Transtornos da Memória/prevenção & controle , Selênio/farmacologia , Animais , Deficiências da Aprendizagem/induzido quimicamente , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Memória/efeitos dos fármacos , Transtornos da Memória/induzido quimicamente , Ratos , Ratos Wistar
7.
Plants (Basel) ; 12(19)2023 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-37836123

RESUMO

Deep learning networks might require re-training for different datasets, consuming significant manual labeling and training time. Transfer learning uses little new data and training time to enable pre-trained network segmentation in relevant scenarios (e.g., different vegetation images in rainy and dry seasons); however, existing transfer learning methods lack systematicity and controllability. So, an MTPI method (Maximum Transfer Potential Index method) was proposed to find the optimal conditions in data and feature quantity for transfer learning (MTPI conditions) in this study. The four pre-trained deep networks (Seg-Net (Semantic Segmentation Networks), FCN (Fully Convolutional Networks), Mobile net v2, and Res-Net 50 (Residual Network)) using the rainy season dataset showed that Res-Net 50 had the best accuracy with 93.58% and an WIoU (weight Intersection over Union) of 88.14%, most worthy to transfer training in vegetation segmentation. By obtaining each layer's TPI performance (Transfer Potential Index) of the pre-trained Res-Net 50, the MTPI method results show that the 1000-TDS and 37-TP were estimated as the best training speed with the smallest dataset and a small error risk. The MTPI transfer learning results show 91.56% accuracy and 84.86% WIoU with 90% new dataset reduction and 90% iteration reduction, which is informative for deep networks in segmentation tasks between complex vegetation scenes.

8.
Psychiatry Res ; 320: 115051, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36652845

RESUMO

The intervention of depression was considered a prevention and treatment option for cardiovascular disease (CVD). However, evidence regarding whether association of depression with mortality differed among people at high or low risk of CVD yielded conflicting results. We aimed to investigate associations between depression and all-cause and CVD mortality among 3854 and 3044 US adults at high and low baseline risk of CVD, respectively. Among participants at high risk of CVD, depression and per 5-point increase in PHQ-9 score were associated with 81% (HR=1.81, 95%CI: 1.15-2.86) and 33% (HR=1.33, 95%CI: 1.14-1.55) increased all-cause mortality, respectively. We did not find statistically significant associations between depression (HR=1.40, 95%CI: 0.67-2.95) and PHQ-9 score (HR=1.28, 95%CI: 1.00-1.63) with CVD mortality due to a small number of mortality events. Among people with low risk of CVD, each 5-point increment in PHQ-9 score was associated with all-cause mortality (HR=1.26, 95%CI: 1.02-1.56), while there was no statistically significant association of depression with all-cause mortality (HR=1.69, 95%CI: 0.75-3.81) and CVD mortality (HR=1.99, 95%CI: 0.83-4.81). This study found that depression was associated with all-cause mortality among individuals at a high baseline risk of CVD, but no significant association was observed in people at a low baseline risk of CVD.


Assuntos
Doenças Cardiovasculares , Humanos , Adulto , Doenças Cardiovasculares/etiologia , Depressão , Fatores de Risco
9.
Foods ; 12(24)2023 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-38137211

RESUMO

The rheological properties and end-use qualities of many foods are mainly determined by the types and levels of grain storage proteins (GSPs) in wheat. GSP levels are influenced by various factors, including tillage management, irrigation, and fertiliser application. However, the effects of irrigation and nitrogen on GSPs remain unclear. To address this knowledge gap, a stationary split-split block design experiment was carried out in low- and high-fertility (LF and HF) soil, with the main plots subjected to irrigation treatments (W0, no irrigation; W1, irrigation only during the jointing stage; W2, irrigation twice during both jointing and flowering stages), subplots subjected to nitrogen application treatments (N0, no nitrogen application; N180, 180 kg/ha; N240, 240 kg/ha; N300, 300 kg/ha), and cultivars tested in sub-sub plots (FDC5, the strong-gluten cultivar Fengdecun 5; BN207, the medium-gluten cultivar Bainong 207). The results showed that GSP levels and processing qualities were significantly influenced by nitrogen application (p < 0.01), N240 was the optimal nitrogen rate, and the influence of irrigation was dependent on soil fertility. Optimal GSP levels were obtained under W2 treatment at LF conditions, and the content was increased by 17% and 16% for FDC5 and BN207 compared with W0 under N240 treatment, respectively. While the optimal GSP levels were obtained under W1 treatments at HF conditions, and the content was increased by 3% and 21% for FDC5 and BN207 compared with W0 under N240 treatment, respectively. Irrigation and nitrogen application increased the glutenin content by increasing Bx7 and Dy10 levels in FDC5, and by increasing the accumulation of Ax1 and Dx5 in BN207. Gliadins were mainly increased by enhancing α/ß-gliadin levels. Correlation analysis indicated that a higher soil nitrate (NO3-N) content increased nitrogen remobilisation in leaves. Path analysis showed that Dy10, Dx5, and γ-gliadin largely determined wet glutenin content (WGC), dough stability time (DST), dough water absorption rate (DWR), and sedimentation value (SV). Therefore, appropriate irrigation and nitrogen application can improve nitrogen remobilisation, GSP levels, and processing qualities, thereby improving wheat quality and production.

10.
Wei Sheng Yan Jiu ; 41(3): 394-8, 2012 May.
Artigo em Zh | MEDLINE | ID: mdl-23050435

RESUMO

OBJECTIVE: To study the effect of lead exposure on synaptic structural plasticity in the hippocampus of postnatal Wistar rats by observing the change of neurons number, the number of synapses and synaptic structural parameters including synaptic cleft, the thinkness of postsynaptic density, synaptic curvature and the width of synaptic active zone. METHODS: Wistar rats, after lactation, 16 pub rats were divided into test group and control group. The test group was given lead dichloride 400 micromol/L by drinking water while the control group with distill water till 2 month old. The hippocampus was taken out after T maze test which was employed to excise their spatial learning and memory ability. Immunohistochemistry method was used to determine the amount of neurons. The number of synapses and the features of synaptic strutural parameters were measured by transmission electron microscope. RESULTS: The blood lead level of the test group was significantly higher than that of the control group (P < 0.05). There was no significant difference between the two groups in the amount of neurons in the CA3 region of hippoeampus (P > 0.05). Compared with the control group, the number of synapses in the test group was reduced (P < 0.05). Among the synaptic strutural parameters, the results revealed a significant increase in the synaptic cleft (P < 0.05), while the thinkness of postsynaptic density, synaptic curvature and the width of synaptic active zone were significantly reduced (P < 0.05 ) comparing the normal control group respectively. CONCLUSION: Lead exposure of low dose affect spatial learning and memory ability in postnatal life not on the amount of hippocampus neurons, but reducing the number of synapses and changing the synaptic parameters, such as the thinkness of postsynaptic density, synaptic curvature and the width of synaptic active zone.


Assuntos
Hipocampo/efeitos dos fármacos , Chumbo/toxicidade , Plasticidade Neuronal/efeitos dos fármacos , Animais , Feminino , Memória , Neurônios , Ratos , Ratos Wistar , Sinapses
11.
J Biosci Bioeng ; 134(4): 311-317, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35931602

RESUMO

The prenylation of compounds has attracted much attention, since it often adds bioactivity to non-prenylated compounds. We employed an enzyme assay with CdpNPT, an indole prenyltransferase from Aspergillus fumigatus with two naturally occurring ß-carbolines, harmine (3) and harman (4) as prenyl acceptors, in the presence of dimethylallyl diphosphate (DMAPP) as the prenyl donor. The enzyme accepted these two prenyl acceptor substrates to produce 6-(3',3'-dimethylallyl)harmine (5) from 3 and 9-(3',3'-dimethylallyl)harman (6) and 6-(3',3'-dimethylallyl)harman (7) from 4. The X-ray crystal structure analysis of the CdpNPT (38-440) truncated mutant complexed with 4, and docking simulation studies of DMAPP to the crystal structure of the CdpNPT (38-440) mutant, suggested that CdpNPT could employ the two-step prenylation mechanism to produce 7, while the enzyme produced 6 with either one- or two-step prenylation mechanisms. Furthermore, the antibacterial assays revealed that the 3',3'-dimethylallylation of 3 and 4, as well as harmol (1), at C-6 enhanced the activities against Staphylococcus aureus and Bacillus subtilis.


Assuntos
Dimetilaliltranstransferase , Antibacterianos/farmacologia , Carbolinas , Dimetilaliltranstransferase/química , Dimetilaliltranstransferase/genética , Dimetilaliltranstransferase/metabolismo , Harmina , Hemiterpenos , Indóis , Compostos Organofosforados , Prenilação , Especificidade por Substrato
12.
J Nat Med ; 76(4): 873-879, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35767141

RESUMO

CdpNPT from Aspergillus fumigatus is a fungal indole prenyltransferase (IPT) with remarkable substrate promiscuity to generate prenylated compounds. Our first investigation of the catalytic potential of CdpNPT against a ß-carboline, harmol (1), revealed that the enzyme also accepts 1 as the prenyl acceptor with dimethylallyl diphosphate (DMAPP) as the prenyl donor and selectively prenylates the C-6 position of 1 by the "regular-type" dimethylallylation to produce 6-(3-dimethylallyl)harmol (2). Furthermore, our X-ray crystal structure analysis of the C-His6-tagged CdpNPT (38-440) truncated mutant complexed with 1 and docking studies of DMAPP to the crystal structure of the CdpNPT (38-440) mutant suggested that CdpNPT could employ the two-step prenylation system to produce 2.


Assuntos
Dimetilaliltranstransferase , Carbolinas , Dimetilaliltranstransferase/genética , Dimetilaliltranstransferase/metabolismo , Indóis , Neopreno , Prenilação , Especificidade por Substrato
13.
Antioxidants (Basel) ; 11(11)2022 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-36421452

RESUMO

Wheat (Triticum aestivum L.) production is severely threatened by an increase in the frequency of drought events. It is crucial to determine stable and effective morphological, physiological, and associated oxidative stress indicators, to evaluate the drought tolerance of wheat for breeding and cultivation. Therefore, the cultivars Luohan 22 (LH 22, drought-tolerant) and Zhengmai 366 (ZM 366, drought-sensitive) were used as experimental materials to analyze the changes in 12 physiological and biochemical indicators, as well as the yield, when the stress was prolonged to different times. Re-watering after 6 days of drought can effectively alleviate the associated oxidative stress of drought to wheat. The physiological responses of plants were reversible when they were re-watered in the range of 6 to 12 days after drought. The degree of recovery of LH 22 was higher than that of ZM 366. Afterwards, seven indicators, including stomatal conductance, proline, malondialdehyde, soluble sugar, hexokinase, glucose, and the non-photochemical quenching parameter, were screened out to characterize tolerance of wheat to drought using the multivariate statistical analytical method. This study further investigated the method of evaluating and indexing tolerance of wheat to drought, from the physiological and biochemical levels. This study can provide a theoretical basis and reference for the selection of wheat cultivars to breed and cultivate against drought stress.

14.
Angew Chem Int Ed Engl ; 50(35): 8161-6, 2011 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-21748835

RESUMO

Divergent route: a direct C-C bond-forming approach to the key aryl-substituted all-carbon quaternary stereogenic center present in bioactive hydrodibenzofuran alkaloids has been discovered. This approach involves an unprecedented organocatalytic enantioselective Michael addition of α-cyanoketones with acrylates and was used in a novel and divergent synthetic strategy for the title compounds in asymmetric fashion.


Assuntos
Alcaloides/síntese química , Alcaloides de Amaryllidaceae/síntese química , Benzofuranos/química , Galantamina/síntese química , Espermidina/análogos & derivados , Alcaloides/química , Alcaloides de Amaryllidaceae/química , Brassicaceae/química , Carbono/química , Catálise , Ciclização , Galantamina/química , Liliaceae/química , Espermidina/síntese química , Espermidina/química , Estereoisomerismo
15.
iScience ; 24(1): 101950, 2021 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-33437937

RESUMO

The multiple mating type system of the Ciliate Tetrahymena thermophila is a self/non-self recognition system, whose specificity resides in a head-to-head, functionally distinct pair of genes, MTA and MTB. We have now sequenced and analyzed these mating type genes in nine additional Tetrahymena species. We conclude that MTA and MTB are derived from a common ancestral gene and have co-evolved for at least ∼150 Myr. We show that T. shanghaiensis, a perpetual selfer (unisexual) species, has a single mating type gene pair, whose MTA and MTB genes likely have different mating type specificity. We document the recent replacement of a complete different set of mating type specificities for another, illustrating how quickly this can happen. We discuss how varying conditions of reproductive stress could result in evolutionary co-adaptations of MTA and MTB genes and changes in mating type determination mechanisms.

16.
iScience ; 24(6): 102669, 2021 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-34159303

RESUMO

[This corrects the article DOI: 10.1016/j.isci.2020.101950.].

17.
Int J Biol Macromol ; 147: 576-581, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31931068

RESUMO

Tetrahymena ribosomal DNA (rDNA) is an ideal system for studying eukaryotic DNA replication and gene transcription. In this study, we developed a new method to isolate rDNA from Tetrahymena cells and used it to sequence and annotate the complete 19,670 bp macronuclear rDNA minichromosome of Tetrahymena pyriformis, a species that lacks the germ-line micronucleus and is unable to undergo sexual reproduction. The key features of T. pyriformis and Tetrahymena thermophila rDNA sequences were then compared. Our results showed (i) the short inverted repeats (M repeats) essential for formation of rDNA minichromosome palindromic structure during sexual reproduction in Tetrahymena are highly conserved in T. pyriformis; (ii) in contrast to T. thermophila, which has two tandem domains that coordinately regulate rDNA replication, T. pyriformis has only a single domain; (iii) the 35S pre-rRNA precursor has 80.25% similarity between the two species; and (iv) the G + C content is higher in the transcribed region than the non-transcribed region in both species, but the GC-skew is more stable in T. pyriformis. The new isolation method and annotated information for the T. pyriformis rDNA minichromosome will provide a useful resource for studying DNA replication and chromosome copy number control in Tetrahymena.


Assuntos
Cromossomos/genética , Replicação do DNA/genética , DNA Ribossômico/genética , Tetrahymena pyriformis/genética , Animais , Análise de Sequência de DNA , Tetrahymena thermophila/genética
18.
Sci Transl Med ; 10(427)2018 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-29437149

RESUMO

There is a clinical need for new bronchodilator drugs in asthma, because more than half of asthmatic patients do not receive adequate control with current available treatments. We report that inhibition of metallothionein-2 protein expression in lung tissues causes the increase of pulmonary resistance. Conversely, metallothionein-2 protein is more effective than ß2-agonists in reducing pulmonary resistance in rodent asthma models, alleviating tension in tracheal spirals, and relaxing airway smooth muscle cells (ASMCs). Metallothionein-2 relaxes ASMCs via transgelin-2 (TG2) and induces dephosphorylation of myosin phosphatase target subunit 1 (MYPT1). We identify TSG12 as a nontoxic, specific TG2-agonist that relaxes ASMCs and reduces asthmatic pulmonary resistance. In vivo, TSG12 reduces pulmonary resistance in both ovalbumin- and house dust mite-induced asthma in mice. TSG12 induces RhoA phosphorylation, thereby inactivating the RhoA-ROCK-MYPT1-MLC pathway and causing ASMCs relaxation. TSG12 is more effective than ß2-agonists in relaxing human ASMCs and pulmonary resistance with potential clinical advantages. These results suggest that TSG12 could be a promising therapeutic approach for treating asthma.


Assuntos
Asma/tratamento farmacológico , Asma/metabolismo , Pulmão/metabolismo , Pulmão/patologia , Proteínas dos Microfilamentos/metabolismo , Proteínas Musculares/metabolismo , Animais , Modelos Animais de Doenças , Camundongos , Camundongos Knockout , Proteínas dos Microfilamentos/agonistas , Proteínas dos Microfilamentos/genética , Simulação de Acoplamento Molecular , Proteínas Musculares/agonistas , Proteínas Musculares/genética
19.
Clin Interv Aging ; 12: 1661-1672, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29070944

RESUMO

BACKGROUND: The clinical assessment of kidney function based on the estimated glomerular filtration rate (GFR) in older patients remains controversial. This study evaluated the concordance and feasibility of using various creatinine-based equations for estimating GFR in elderly Chinese patients with type 2 diabetes mellitus (T2DM). METHODS: A cross-sectional analytical study was conducted in 21,723 older diabetic patients (≥60 years) based on electronic health records (EHR) for Minhang District, Shanghai, China. The concordance of chronic kidney disease (CKD) classification among different creatinine-based equations was assessed based on Kappa values, intraclass correlation coefficient (ICC) statistics, and the eGFR agreement between the equations was tested using Bland-Altman plots. The GFR was estimated using the Cockcroft-Gault (CG), Berlin Initiative Study 1 (BIS1), simplified Modification of Diet in Renal Disease (MDRD), MDRD modified for Chinese populations (mMDRD), chronic kidney disease epidemiology collaboration (CKD-EPI), CKD-EPI in Asians (CKD-EPI-Asia), and Ruijin equations. RESULTS: Overall, the proportion of CKD stages 3-5 (eGFR <60 mL/min/1.73 m2) was calculated as 28.9%, 39.1%, 11.8%, 8.4%, 14.3%, 11.5%, and 12.7% by the eGFRCG, eGFRBIS1, eGFRMDRD, eGFRmMDRD, eGFRCKD-EPI, eGFRCKD-EPI-Asia, and eGFRRuijin equations, respectively. The concordance of albuminuria and decreased eGFR based on the different equations was poor by both the Kappa (<0.2) and ICC (<0.4) statistics. The CKD-EPI-Asia equation resulted in excellent concordance with the CKD-EPI (ICC =0.931), MDRD (ICC =0.963), mMDRD (ICC =0.892), and Ruijin (ICC =0.956) equations for the classification of CKD stages, whereas the BIS1 equation exhibited good concordance with the CG equation (ICC =0.809). In addition, significant differences were observed for CKD stage 1 among all these equations. CONCLUSION: Accurate GFR values are difficult to estimate using creatinine-based equations in older diabetic patients. Kidney function is complex, and the staff need to be aware of the individualized consideration of other risk factors or markers of reduced renal function in clinical practice.


Assuntos
Diabetes Mellitus Tipo 2/epidemiologia , Taxa de Filtração Glomerular , Insuficiência Renal Crônica/epidemiologia , Insuficiência Renal Crônica/fisiopatologia , Idoso , Biomarcadores/análise , China/epidemiologia , Creatinina/análise , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Insuficiência Renal/epidemiologia , Insuficiência Renal/fisiopatologia , Fatores de Risco
20.
Can Respir J ; 2016: 1462563, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-28050155

RESUMO

Background. Asthma is a disease with a core abnormality in airway smooth muscle function, and the proliferation of airway smooth muscle cells (ASMCs) plays a pivotal role in asthma airway remodeling. Our previous study showed that S100A9 (S100 calcium-binding protein A9; 400 and 800 ng/mL) significantly inhibited rat ASMCs proliferation at 48 h, and 50-800 ng/mL S100A9 (50, 100, 200, 400, and 800 ng/mL) also induced a lasting effect by significantly inhibiting rat ASMCs proliferation at 72 h in a dose-dependent manner. However, the intracellular effects of S100A9 on ASMCs proliferation remain unknown. Methods. Rat ASMCs with stable S100A9 knockdown were generated using short hairpin RNA. The effects of decreased S100A9 expression on cellular proliferation, the production of reactive oxygen species (ROS), and p38 MAPK pathway protein expression were examined. Results. Decreased intracellular S100A9 expression significantly promoted platelet-derived growth factor-induced rat ASMCs proliferation and increased ROS production. The antioxidative agent N-acetylcysteine significantly inhibited rat ASMCs proliferation. Western blot results showed that the decreased intracellular S100A9 expression significantly inhibited p38 MAPK phosphorylation. Conclusion. Decreased S100A9 expression promoted rat ASMCs proliferation by stimulating ROS generation and inhibiting p38 MAPK. Our study may provide novel insights into the regulation of asthma airway remodeling.


Assuntos
Asma/fisiopatologia , Calgranulina B/fisiologia , Proliferação de Células , Miócitos de Músculo Liso/fisiologia , Animais , Asma/metabolismo , Células Cultivadas , Sistema de Sinalização das MAP Quinases , Ratos , Espécies Reativas de Oxigênio/metabolismo
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