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1.
J Am Chem Soc ; 2024 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-38743719

RESUMEN

Electrocatalytic water oxidation is a key transformation in many strategies designed to harness solar energy and store it as chemical fuels. Understanding the mechanism(s) of the best electrocatalysts for water oxidation has been a fundamental chemical challenge for decades. Here, we quantitate evolved dioxygen isotopologue composition via gas-phase EPR spectroscopy to elucidate the mechanisms of water oxidation on metal oxide electrocatalysts with high precision. Isotope fractionation is paired with computational and kinetic modeling, showing that this technique is sensitive enough to differentiate O-O bond-forming steps. Strong agreement between experiment and theory indicates that for the nickel-iron layered double hydroxide─one of the best earth-abundant electrocatalysts to be studied─water oxidation proceeds via a dioxo coupling mechanism to form a side-bound peroxide rather than a hydroxide attack to form an end-bound peroxide.

2.
Sci Adv ; 10(7): eadk1721, 2024 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-38363834

RESUMEN

Characterizing the tumor microenvironment at the molecular level is essential for understanding the mechanisms of tumorigenesis and evolution. However, the specificity of the blood proteome in localized region of the tumor and its linkages with other systems is difficult to investigate. Here, we propose a spatially multidimensional comparative proteomics strategy using glioma as an example. The blood proteome signature of tumor microenvironment was specifically identified by in situ collection of arterial and venous blood from the glioma region of the brain for comparison with peripheral blood. Also, by integrating with different dimensions of tissue and peripheral blood proteomics, the information on the genesis, migration, and exchange of glioma-associated proteins was revealed, which provided a powerful method for tumor mechanism research and biomarker discovery. The study recruited multidimensional clinical cohorts, allowing the proteomic results to corroborate each other, reliably revealing biological processes specific to gliomas, and identifying highly accurate biomarkers.


Asunto(s)
Neoplasias Encefálicas , Glioma , Humanos , Proteómica/métodos , Neoplasias Encefálicas/patología , Proteoma/metabolismo , Glioma/patología , Biomarcadores , Microambiente Tumoral
3.
Neuroepidemiology ; 2024 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-38290491

RESUMEN

OBJECTIVE: Parkinson's Disease (PD) is a profoundly incapacitating neurodegenerative disorder, which presents a substantial challenge to the economic sustainability of the global healthcare system. The present study seeks to clarify the factors that contribute to the costs associated with PD hospitalization and analyze the economic burden it imposes. METHODS: We examined data of 19,719 patients with a primary diagnosis of PD who were admitted to hospitals in Hubei Province, China, during the study period. Healthcare data were obtained from the database of electronic medical records. The study presents a comprehensive analysis of the demographic characteristics and investigates the factors that affect their healthcare expenditure. RESULTS: The cohort consisted of 10,442 (53.0%) males and 9,277 (47.0%) females. The age group of 66-70 years experienced the highest incidence of hospitalization among PD patients, with a mortality rate of 0.76‰. The average length of stay for patients was 9.9 ± 8.6 days and the average cost per patient was $1759.9 ± 4787.7. Surgical interventions were conducted on a mere 2.0% of the total inpatient population. The primary cost component for these interventions was material expenses, accounting for 70.1% of the total. Non-surgical patients primarily incurred expenses related to diagnosis and medication. Notably, surgical patients faced a substantial out-of-pocket rate, reaching up to 90.6%. Surgery was identified as the most influential factor that negatively affected both length of stay and hospitalization costs. Inpatients exhibited significant associations with prolonged length of stay and increased medical expenditure as age increased. Male patients had significantly longer hospital stays and higher medical costs than did females. Additionally, patient's occupation and type of medical insurance exerted significant effects on both length of stay and medical expense. CONCLUSION: Age significantly affects PD hospitalization costs. Given the prevailing demographic shift towards an aging population, the government's medical insurance burden related to PD will continue to escalate. Meanwhile, high treatment expenses and out-of-pocket rates impose substantial financial burdens on patients, limiting surgical intervention access to a small fraction of patients. Addressing these issues is of utmost importance in order to ensure comprehensive disease management for the majority of individuals affected by PD.

4.
Dalton Trans ; 52(37): 13079-13088, 2023 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-37668338

RESUMEN

Electrocatalysts with a high oxygen evolution reaction (OER) activity are very important for electrochemical water oxidation, but they are also challenging. In this study, N-doped graphene-like supported highly dispersed bimetallic NiCoP NPs as an efficient electrocatalyst for water oxidation were prepared by using cation exchange resin as a carbon source and by loading cobalt and nickel on D001 by a high-temperature calcination method. The designed electrocatalyst with bimetallic phosphide as the active center shows excellent OER catalytic performance, with an overpotential of 324 mV at 10 mA cm-2 and a corresponding Tafel slope of 97.28 mV dec-1. The increase in NiCoP-3@GL activity may be due to the increase in surface area (933.49 m2 g-1) caused by the irregular morphology, rich interface contact, and porous structure. In addition, the strong combination of NiCoP and GL improves the structural stability and durability of the electrocatalyst. After 5000 cyclic voltammetry tests, the performance of the catalyst decreased by 16.9 %. This work provides a new idea for designing efficient bimetallic phosphide electrocatalysts.

5.
Small ; 19(43): e2302768, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37381638

RESUMEN

The Li-CO2 battery has great potential for both CO2 utilization and energy storage, but its practical application is limited by low energy efficiency and short cycle life. Efficient cathode catalysts are needed to address this issue. Herein, this work reports on molecularly dispersed electrocatalysts (MDEs) of nickel phthalocyanine (NiPc) anchored on carbon nanotubes (CNTs) as the cathode catalyst for Li-CO2 batteries. The dispersed NiPc molecules efficiently catalyze CO2 reduction, while the conductive and porous CNTs networks facilitate CO2 evolution reaction, leading to enhanced discharging and charging performance compared to the NiPc and CNTs mixture. Octa-cyano substitution on NiPc (NiPc-CN) further enhances the interaction between the molecule and CNTs, resulting in better cycling stability. The Li-CO2 battery with the NiPc-CN MDE cathode shows a high discharge voltage of 2.72 V and a small discharging-charging potential gap of 1.4 V, and can work stably for over 120 cycles. The reversibility of the cathode is confirmed by experimental characterizations. This work lays a foundation for the development of molecular catalysts for Li-CO2 battery cathodes.

6.
Front Oncol ; 13: 1161496, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37035181

RESUMEN

Background: Reoperation may be beneficial for patients with recurrent gliomas. Minimizing the residual tumor volume (RTV) while ensuring the functionality of relevant structures is the goal of the reoperation of recurrent gliomas. Intraoperative ultrasound (IoUS) may be helpful for intraoperative tumor localization, intraoperative real-time imaging to guide surgical resection, and postoperative evaluation of the RTV in the reoperation for recurrent gliomas. Objective: To assess the effect of real-time ioUS on minimizing RTV in recurrent glioma surgery compared to Non-ioUS. Methods: We retrospectively analyzed the data from 92 patients who had recurrent glioma surgical resection: 45 were resected with ioUS guidance and 47 were resected without ioUS guidance. RTV, Karnofsky Performance Status (KPS) at 6 months after the operation, the number of recurrent patients, and the time to recurrence were evaluated. Results: The average RTV in the ioUS group was significantly less than the Non-ioUS group (0.27 cm3 vs. 1.33 cm3, p = 0.0004). Patients in the ioUS group tended to have higher KPS scores at 6 months of follow-up after the operation than those in the Non-ioUS group (70.00 vs. 60.00, p = 0.0185). More patients in the Non-ioUS group experienced a recurrence than in the ioUS group (43 (91.49%) vs. 32 (71.11%), p = 0.0118). The ioUS group had a longer mean time to recurrence than the Non-ioUS group (7.9 vs. 6.3 months, p = 0.0013). Conclusion: The use of ioUS-based real-time for resection of recurrent gliomas has been beneficial in terms of both RTV and postoperative outcomes, compared to the Non-ioUS group.

7.
Mol Genet Genomic Med ; 11(2): e2100, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36370055

RESUMEN

BACKGROUND: Nance-Horan syndrome (NHS) is a rare and often overlooked X-linked dominant disorder characterized by dense congenital cataracts, dental abnormalities, and mental retardation. The majority of NHS variations include frameshift mutations, nonsense mutations, microdeletions, and insertions. METHODS: Copy number variation sequencing was performed to determine the microdeletion. The expression of NHS was detected by RT-PCR. Four family members were tested for X chromosome inactivation. RESULTS: In this study, all members were examined for systemic examinations and genetic testing of four members and two affected subjects are observed. We identified a heterozygous microdeletion of -0.52 Mb at Xp22.13 in a female proband presenting NHS phenotypically. The microdeletion contains the REPS2 and NHS genes and was inherited from a phenotypically normal mother. Of interest, the expression NHS of proband was reduced and the skewed X chromosome inactivation rate reached more than 85% compared with her mother and the control. It was concluded that the haploinsufficiency of the NHS gene may account for the majority of clinical symptoms in the affected subjects. The variability among female carriers presumably results from nonrandom X chromosome inactivation. CONCLUSION: Our findings broaden the spectrum of NHS mutations and provide molecular insight into NHS clinical prenatal genetic diagnosis.


Asunto(s)
Catarata , Variaciones en el Número de Copia de ADN , Humanos , Femenino , Linaje , Inactivación del Cromosoma X , Proteínas Nucleares/genética , Proteínas de la Membrana/genética , Catarata/genética , Proteínas de Unión al Calcio/genética
8.
China Tropical Medicine ; (12): 529-2023.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-979747

RESUMEN

@#Abstract: Objective To master the condition of cockroach population distribution, seasonal dynamics, cockroach density for different habitat, and to provide a basis for developing cockroach control strategies. Methods Six types of surveillance sites, including residential areas, hotels, restaurants, supermarkets, hospitals and farm product markets, were set up in 14 cities in Liaoning to monitor cockroaches using the sticky-trap method. The cockroach surveillance data from vector surveillance sites in fourteen cities of Liaoning Province in 2021 were collected and statistically analyzed using Excel 2010 and SPSS 23.0 software. The density and species composition of cockroaches were analyzed, and the density difference and seasonal dynamics trend of cockroaches in different habitats were compared. Results A total of 3 031 cockroaches were captured in 2021, of which Blattella germanica accounted for 94.66% (2 869/3 031) and was the dominant population. The total density of cockroaches was 0.230 0 cockroaches per sheet (3 031/13 234) and the total infestation rate of cockroaches was 5.59% (562/10 052). The density and infestation rate of cockroaches in different habitats were in the order of farm product markets, restaurants, and hotels and the difference in infestation rate between habitats was statistically significant (χ2=168.327, P<0.05). The seasonal dynamics trend of cockroach density and disoperation rate showed a unimodal curve, and the peaks were distributed in July. The seasonal dynamics of cockroach density and disoperation rate in different habitats showed a unimodal curve in the habitats of farm product markets, supermarkets, hotels, hospitals and residential areas all, while the habitats of restaurants were close to a double peak curve. Conclusions B. germanica is the dominant species of cockroaches in Liaoning Province in 2021. Compared with 2020 the density and disoperation rate of cockroach in 2021 showed a slight downward trend, and the seasonal dynamics trend of cockroach density and disoperation rate showed a unimodal curve. The farm product markets are the key places for cockroach prevention and control. According to the seasonal fluctuation trends in cockroach density and infestation rate in different habitats, comprehensive prevention and control measures should be taken before the peak periods to reduce cockroach density and control diseases.

9.
Front Neurol ; 14: 1344672, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38375353

RESUMEN

Objective: To evaluate the effectiveness of combined resection and radiotherapy (CRAR) for the treatment of primary pineal malignant melanoma (PPMM). Methods: Relevant studies were identified through a literature search in PubMed, Embase, and Web of Science from 1899 to September 1, 2023. Then we further screened the literature according to the updated PRISMA 2020 guidelines. The article information, patient information, treatment, and survival rate were analyzed. The primary outcome measures the survival rate of CRAR compared with the overall patients and the patients without treatment. Secondary outcome measures operation methods, radiotherapy methods, and dose. Results: In total, 28 published articles were recorded. Among them, 35.71% (10/28) articles were on CRAR. The median overall survival, CRAR, and no treatment survival were 65, 88, and 12 weeks, respectively. The median overall survival of CRAR was demonstrably better than that of no treatment (p < 0.0001) and overall survival, even with p = 0.1177. Most of the operations adopted a supracerebellar infratentorial approach, and stereotactic radiation to tumor bed usually ranged between 50 and 60 Gy. Small dose and multiple fractions was the most popular radiotherapy method. Conclusion: Currently, CRAR, compared with other treatments, is more beneficial to prolonging the survival of PPMM patients. However, many more clinical cases are needed to verify it as the best treatment approach.

10.
Front Neurol ; 14: 1333665, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38274891

RESUMEN

Objective: We designed a novel intraoperative malleable adjustable continuous suction tube to obtain clear surgical fields, reduce intracranial pressure, and lower the temperature of the surgical area. Methods: This device consists of six parts: continuous suction tube head and cotton patty, suction tube, fixed wire position, fixed clip, spiral plastic pressure regulating valve, and tail. It can continuously extract blood, cerebrospinal fluid, and rinsing solution from surgical fields, with minimal contact and trauma to tissues, nerves, and blood vessels, while also having a negligible impact on the surgeon's focus and procedure. Result: The excellent and safe performance (simple, malleable, adjustable, space-saving, inexpensive, safe, and effective) of this device in clearing the operating field has been proven in more than 2000 neurosurgical operative procedures. We encountered no complications associated with this device, such as cerebral hematoma, postoperative low intracranial pressure, or vascular and nerve injuries. Conclusion: The newly innovated intraoperative malleable adjustable continuous suction tube is effective and safe for microneurosurgery.

11.
Front Plant Sci ; 13: 1050064, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36457517

RESUMEN

Zhengdan 958 (ZD958) is the summer maize variety with the widest planting area in Huang-Huai-Hai plain in the past 20 years. Understanding the agronomic characteristics of maize and its adaptability to climatic factors is of great significance for breeding maize varieties with high yield and stability. In this study, the experimental data of 33 experimental stations from 2005 to 2015 were analyzed to clarify the effects of different agronomic traits on yield and the correlation between agronomic traits, and to understand the effects of different climatic factors on summer maize yield and agronomic traits. The results showed that the average yield of ZD958 was 9.20 t ha-1, and the yield variation coefficient was 13.41%. There was a certainly negative correlation between high yield and high stability. Plant heights, ear heights, double ear rate, ear length, ear rows, line grain number, grain number per ear, ear diameter, cob diameter, and 1000 grains weight were significantly positive correlation with maize yield. Solar radiation before and after silking were significantly positive correlation with maize yield. Path analysis showed that changes in agronomic traits accounted for 54% of the yield variation, and changes in climate factors accounted for 26% of the yield variation. Our study showed that higher plant height, ear height, grain number per ear and 1000-grain weight, lower lodging rate, pour the discount rate and shorter bald tip long were the main reasons for high yield. Among the climatic factors, solar radiation and the lowest temperature have significant effects on the yield.

12.
Front Neurol ; 13: 979494, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36204001

RESUMEN

Background: An essential surgical tool in neurosurgery is the suction tube. The skillful and accurate use of a suction tube facilitates the neurosurgical operation. Objective: This study is to verify the practicality of an adjustable pressure suction tube (APS tube) and to explore the ideal APS tube diameter and tip negative pressure for different intracranial structures. Methods: APS tubes were used to aspirate brain tissues and carotid arteries of rats. Laser speckle contrast imaging (LSCI) was used to record the blood flow velocity (BFV). We measured APS tube diameter, air inlet size, tip negative pressure and central negative pressure and calculated the correlation between them. In our department, intraoperative real-time parameters including APS tube diameter, length, air inlet size, and central negative pressure were recorded, and the tube tip negative pressure suitable for different intracranial structures and parts was calculated. Results: All experiments were carried out using APS tubes. Experiments on rats objectively reflected a severe structural damage to the brain and blood vessels by the suction tube, which might even result in an irreversible reduction in blood flow., Rat carotid arteries and brain tissue suffered severe damage when the tip negative pressure exceeded 33.4 ± 1.8 and 29.2 ± 2.0 kPa, respectively. BFV failed to return to the preoperative level 3 min after the operation (p < 0.05), and this decrease was more pronounced when the suction tube diameter was large (p < 0.05). The tip negative pressure was positively and negatively correlated with central negative pressure and the air inlet size, and was independent of APS tube diameter. A total of 50 operations including 39 tumor resection operations and 11 moyamoya disease bypass operations were recorded. Large-diameter APS tubes (3.5 mm) with an closed air inlet were frequently used to maintain a greater tip negative pressure before the incision of dura mater. When important structures such as motor cortex and brainstem were involved, 1.5- or 2.0-mm-diameter APS tubes were mostly used, and an air inlet was opened up to 0.7-2.1 mm to maintain a safe tip negative pressure (7.4-27.9 kPa). Conclusion: APS tubes with a mechanical knob provide stable and precise adjustment of the tip negative pressure, avoiding excessive negative pressure that causes serious damage to the intracranial structure. And, this allows the surgeon to hold the suction tube more freely and operate at any angle with an appropriate fulcrum near the incision to achieve efficient atraumatic suction and enhance surgical safety.

13.
Nat Commun ; 13(1): 3177, 2022 06 08.
Artículo en Inglés | MEDLINE | ID: mdl-35676274

RESUMEN

The assembly and function of the yeast general transcription factor TFIID complex requires specific contacts between its Taf14 and Taf2 subunits, however, the mechanism underlying these contacts remains unclear. Here, we determined the molecular and structural basis by which the YEATS and ET domains of Taf14 bind to the C-terminal tail of Taf2 and identified a unique DNA-binding activity of the linker region connecting the two domains. We show that in the absence of ligands the linker region of Taf14 is occluded by the surrounding domains, and therefore the DNA binding function of Taf14 is autoinhibited. Binding of Taf2 promotes a conformational rearrangement in Taf14, resulting in a release of the linker for the engagement with DNA and the nucleosome. Genetic in vivo data indicate that the association of Taf14 with both Taf2 and DNA is essential for transcriptional regulation. Our findings provide a basis for deciphering the role of individual TFIID subunits in mediating gene transcription.


Asunto(s)
Proteínas de Saccharomyces cerevisiae , Factores Asociados con la Proteína de Unión a TATA , Factor de Transcripción TFIID , ADN/metabolismo , Regulación de la Expresión Génica , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Factores Asociados con la Proteína de Unión a TATA/metabolismo , Factor de Transcripción TFIID/metabolismo
14.
Front Neurol ; 13: 879250, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35592473

RESUMEN

Objective: The purpose of this study was to evaluate the safety, efficiency, and cost expenditure of remote programming in patients with Parkinson's disease (PD) after deep brain stimulation (DBS). Methods: A total of 74 patients who underwent DBS at the Department of Neurosurgery, Zhongnan Hospital of Wuhan University between June 2018 and June 2020 were enrolled in this study. There were 27 patients in the remote programming group and 47 patients in the outpatient programming group. Clinical data, programming efficiency, adverse events, expenditure, and satisfaction were compared between the two groups. Results: A total of 36 times of remote programming were performed on the 27 patients in the remote programming group, and four had mild adverse events during programming, and the adverse events disappeared within 1 week. The satisfaction questionnaire showed that 97.3% of the patients were satisfied with the surgical effect. The patients in the remote programming group (88.9%) were more likely to receive long-term programming after DBS than the patients in the outpatient programming group (74.5%). The Parkinsonism symptoms improved in both programming groups. The majority (18/27) of patients in the remote programming group lived away from the programming center, while the majority (27/47) of patients in the outpatient programming group lived in Wuhan, where the programming center was located (P = 0.046). The cost per patient per programming was US$ 43.5 in the remote programming group and $59.5 (56-82.7) in the outpatient programming group (P < 0.001). The median time cost for each visit was 30 min (25-30) in the remote programming group and 150 min (135-270.0) in the outpatient programming group (P < 0.001). Conclusion: Remote programming is safe and effective after DBS in patients with Parkinson's disease. Moreover, it reduces expenditure and time costs for patients and achieves high satisfaction, particularly for patients living far from programming centers.

15.
Am J Transl Res ; 14(3): 1909-1922, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35422942

RESUMEN

OBJECTIVE: Withdrawal of levodopa (L-dopa) the night before subthalamic nucleus-deep brain stimulation (STN-DBS) procedures have been a standard practice, although some patients experienced severe withdrawal symptoms. In this cohort study, we investigated the effects of continuing preoperative L-dopa therapy on intraoperative microelectrode recording (MER), intraoperative cooperation and the clinical outcome for deep brain stimulation (DBS) which was performed under local anesthesia. METHODS: The study included 99 patients with Parkinson's disease who were treated with bilateral STN-DBS between October 2014 and August 2018. The patients were followed for 12 months postoperatively and divided into "on-medication" and "off-medication" groups. The length of MER recordings, the number of microelectrode tracks, intraoperation cooperation, operation duration, and clinical outcomes were compared between the two groups. RESULTS: The length of MER recording was longer in the "on-medication" group in both the left and right subthalamic nucleus (STN; P<0.001 and P=0.007, respectively). The unified Parkinson's disease rating scale (UPDRS) motor score indicated better improvement in the "on-medication" group at postoperative one month, six months and twelve months (P=0.045, P=0.034 and P=0.001 respectively). Patients in "on-medication" group could cooperate better with a shorter operation duration (177.9 vs. 195 min, P=0.038). Reduction in L-dopa equivalent dose (LED) and improvement of Hoehn-Yahr scale were comparable between the two groups during the follow-up period. CONCLUSION: The continuation of L-dopa therapy prior to DBS procedures had no impediment on MER and can contribute to reducing the duration of operation, and benefit the electrode insertion, as well as the clinical outcomes.

16.
Phys Chem Chem Phys ; 24(11): 6742-6756, 2022 Mar 16.
Artículo en Inglés | MEDLINE | ID: mdl-35234766

RESUMEN

Organic materials with controllable molecular design and sustainable resources are promising electrode materials. Crystalline quinones have been investigated in a variety of rechargeable battery chemistries due to their ubiquitous nature, voltage tunability and environmental friendliness. In acidic electrolytes, quinone crystals can undergo proton-coupled electron transfer (PCET), resulting in charge storage. However, the detailed mechanism of this phenomenon remains elusive. To model PCET in crystalline quinones, force field-based methods are not viable due to variable redox states of the quinone molecules during battery operation and computationally efficient quantum mechanical methods are strongly desired. The semi-empirical density functional tight-binding (DFTB) method has been widely used to study inorganic crystalline systems and biological systems but has not been comprehensively benchmarked for studying charge transport in quinones. In this work, we benchmark the third order variant of DFTB (DFTB3) for the reduction potential of quinones in aqueous solution, energetics of proton transfer between quinones and between quinones and water, and structural and electronic properties of crystalline quinones. Our results reveal the deficiencies of the DFTB3 method in describing the proton affinity of quinones and the structural and electronic properties of crystalline quinones, and highlight the need for further development of the DFTB method for describing charge transport in crystalline quinones.


Asunto(s)
Benchmarking , Quinonas , Electrónica , Oxidación-Reducción , Protones , Quinonas/química
17.
Inorg Chem ; 60(23): 17445-17449, 2021 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-34813328

RESUMEN

Here we report electrochemical, spectroscopic, and crystallographic characterization of a redox series of cobalt complexes in five sequential oxidation states. A simple bidentate phosphine ligand, cis-1,2-bis(diphenylphosphino)ethylene (dppv), allows for isolation of the 3+, 2+, 1+, 0, and 1- oxidation states of cobalt─the only known example of transition-metal complexes with redox-innocent ligands in five oxidation states. Electrochemistry of [Co(dppv)2]2+ reveals three reversible reductions and one reversible oxidation. Complexes in each oxidation state are characterized using single-crystal X-ray diffraction. The coordination number and geometry of the complex changes as a function of the oxidation state: including acetonitrile ligands, the Co3+ complex is pseudo-octahedral, the Co2+ complex is square-pyramidal, the Co+ complex is pseudo-square-planar, and the Co0 and Co- complexes approach pseudo-tetrahedral, illustrating structures predicted by crystal-field theory of inorganic transition-metal complexes.

18.
Genes Dev ; 35(23-24): 1678-1692, 2021 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-34819351

RESUMEN

How transcription programs rapidly adjust to changing metabolic and cellular cues remains poorly defined. Here, we reveal a function for the Yaf9 component of the SWR1-C and NuA4 chromatin regulatory complexes in maintaining timely transcription of metabolic genes across the yeast metabolic cycle (YMC). By reading histone acetylation during the oxidative and respiratory phase of the YMC, Yaf9 recruits SWR1-C and NuA4 complexes to deposit H2A.Z and acetylate H4, respectively. Increased H2A.Z and H4 acetylation during the oxidative phase promotes transcriptional initiation and chromatin machinery occupancy and is associated with reduced RNA polymerase II levels at genes-a pattern reversed during transition from oxidative to reductive metabolism. Prevention of Yaf9-H3 acetyl reading disrupted this pattern of transcriptional and chromatin regulator recruitment and impaired the timely transcription of metabolic genes. Together, these findings reveal that Yaf9 contributes to a dynamic chromatin and transcription initiation factor signature that is necessary for the proper regulation of metabolic gene transcription during the YMC. They also suggest that unique regulatory mechanisms of transcription exist at distinct metabolic states.


Asunto(s)
Histonas , Proteínas de Saccharomyces cerevisiae , Acetilación , Cromatina/metabolismo , Histona Acetiltransferasas/metabolismo , Histonas/metabolismo , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo
19.
Front Genet ; 12: 715437, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34707637

RESUMEN

BACKGROUND: Tyrosinase-positive oculocutaneous albinism (OCA, type II, OCA2) is an autosomal recessive genetic disease in which the biosynthesis of melanin decreases in the skin, hair, and eyes. OCA2 disease is caused by mutations in OCA2 gene. The gene product plays a role in regulating the pH of melanosomes. Up to now, hundreds of OCA2 mutations have been reported and novel variants are still being discovered. METHODS: In this study, we reviewed the records of OCA2 patients who had conducted albinism genetic testing, and then analyzed the clinical and genetic information of 28 OCA2 patients who had been genetically diagnosed by using Sanger sequencing and next-generation sequencing. RESULTS: In this study, we reported 31 variants screened from 28 Chinese OCA2 families, and characterized the detailed molecular and clinical presentations. There were 12 novel variants among all detected variants, including 3 missense variants (p.G393V, p.T482A, and p.R720P), 4 frameshift variants (p.R53Gfs∗49, p.N279Kfs∗17, p.I469Lfs∗4, p.I655Nfs∗12), 2 splicing variants (c.1637-2A > G, c.1951 + 1G > C), 2 stopgain variants (p.L278X, p.W652X) and 1 insertion variants (p.P315LinsT). One potential cluster of missense variants was implicated indicating the important roles of the underlying domains in OCA2 pathogenesis. CONCLUSION: Our results were beneficial for diagnosis and precision clinical management for OCA2-related disorder, and this study expanded the mutation spectrum of oculocutaneous albinism.

20.
ACS Appl Mater Interfaces ; 13(36): 42715-42723, 2021 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-34473475

RESUMEN

Electrochemical methods are promising technical routes for future clean energy storage and conversion. Most of the electrochemical methods involve oxygen reactions. Unfavorable kinetics and sluggish reactions are the main challenges for these processes. We report here a facile synthesis of highly efficient oxygen evolution reaction (OER) and oxygen reduction reaction (ORR) catalysts. The catalysts are synthesized through the fine-tuning of metal ions (M, specifically Co, Ni, Zn, and Cu) in Prussian blue analogues (PBAs) and thus termed as M-PBAs. The CoNi-PBA-2 catalyst shows the highest activity toward OER with an onset potential at 280 mV and a Tafel slope of 63 mV dec-1. Zn-PBA catalysts demonstrate high selectivity in two-electron-transfer ORR. The H2O2 yield is as high as 88% at 0 V vs RHE. Density functional theory (DFT) calculations also confirm the high selectivity of Zn-PBA toward H2O2 in ORR.

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