Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 27
Filtrar
Mais filtros










Intervalo de ano de publicação
1.
Proc Natl Acad Sci U S A ; 121(24): e2321619121, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38833475

RESUMO

Angiotensin-convertingenzyme 2 (ACE2) has dual functions, regulating cardiovascular physiology and serving as the receptor for coronaviruses. Bats, the only true flying mammals and natural viral reservoirs, have evolved positive alterations in traits related to both functions of ACE2. This suggests significant evolutionary changes in ACE2 during bat evolution. To test this hypothesis, we examine the selection pressure in ACE2 along the ancestral branch of all bats (AncBat-ACE2), where powered flight and bat-coronavirus coevolution occurred, and detect a positive selection signature. To assess the functional effects of positive selection, we resurrect AncBat-ACE2 and its mutant (AncBat-ACE2-mut) created by replacing the positively selected sites. Compared to AncBat-ACE2-mut, AncBat-ACE2 exhibits stronger enzymatic activity, enhances mice's performance in exercise fatigue, and shows lower affinity to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Our findings indicate the functional pleiotropy of positive selection in the ancient ACE2 of bats, providing an alternative hypothesis for the evolutionary origin of bats' defense against coronaviruses.


Assuntos
Enzima de Conversão de Angiotensina 2 , Quirópteros , Seleção Genética , Quirópteros/virologia , Quirópteros/genética , Animais , Enzima de Conversão de Angiotensina 2/genética , Enzima de Conversão de Angiotensina 2/metabolismo , Camundongos , Pleiotropia Genética , Evolução Molecular , SARS-CoV-2/genética , COVID-19/virologia , COVID-19/genética , Coronavirus/genética , Humanos , Filogenia
2.
J Am Chem Soc ; 146(5): 3373-3382, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38272666

RESUMO

Reticular chemistry effectively yields porous structures with distinct topological lattices for a broad range of applications. Polyhedral oligomeric silsesquioxane (POSS)-based octatopic building blocks with a rare Oh symmetric configuration and attracting inorganic features have great potential for creating three-dimensional (3D) covalent organic frameworks (COFs) with new topologies. However, the intrinsic flexibility and intensive motion of cubane-type POSS molecules make the construction of 3D regular frameworks challenging. Herein, by fastening three or four POSS cores with per aromatic rigid linker from rational steric directions, we successfully developed serial crystalline 3D COFs with unpresented "the" and scu topologies. Both the experimental and theoretical results proved the formation of target 3D POSS-based COFs. The resultant hybrid networks with designable chemical skeletons and high surface areas maintain the superiorities of both the inorganic and organic components, such as their high compatibility with inorganic salts, abundant periodic electroactive sites, excellent thermal stability, and open multilevel nanochannels. Consequently, the polycubane COFs could serve as outstanding solid electrolytes with a high ionic conductivity of 1.23 × 10-4 S cm-1 and a lithium-ion transference number of 0.86 at room temperature. This work offers a pathway to generate ordered lattices with multiconnected flexible cube motifs and enrich the topologies of 3D COFs for potential applications.

3.
Circ Cardiovasc Imaging ; 16(9): e015773, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37725669

RESUMO

BACKGROUND: Coronary computed tomography angiography (CCTA) and cardiac magnetic resonance (CMR) have been used to diagnose lesion-specific ischemia in patients with coronary artery disease. The aim of this study was to investigate the diagnostic performance of CCTA-derived plaque characteristic index compared with myocardial blood flow (MBF) and myocardial perfusion reserve (MPR) derived from CMR perfusion in the assessment of lesion-specific ischemia. METHODS: Between October 2020 and March 2022, consecutive patients with suspected or known coronary artery disease, who were clinically referred for invasive coronary angiography were prospectively enrolled. All participants sequentially underwent CCTA and CMR and invasive fractional flow reserve within 2 weeks. The diagnostic performance of CCTA-derived plaque characteristics, CMR perfusion-derived stress MBF, and MPR were compared. Lesions with fractional flow reserve ≤0.80 were considered to be hemodynamically significant stenosis. RESULTS: Nighty-two patients with 141 vessels were included in this study. Plaque length, minimum luminal area, plaque area, percent area stenosis, total atheroma volume, vessel volume, lipid-rich volume, spotty calcium, napkin-ring signs, stress MBF, and MPR in flow-limiting stenosis group were significantly different from nonflow-limiting group. The overall accuracy, sensitivity, specificity, positive predictive value, and negative predictive value of lesion-specific ischemia diagnosis were 61.0%, 55.3%, 63.1%, 35.6%, and 79.3% for stress MBF, and 89.4%, 89.5%, 89.3%, 75.6%, 95.8% for MPR; meanwhile, 82.3%, 79.0%, 84.5%, 65.2%, and 91.6% for CCTA-derived plaque characteristic index. CONCLUSIONS: In our prospective study, CCTA-derived plaque characteristics and MPR derived from CMR performed well in diagnosing lesion-specific myocardial ischemia and were significantly better than stress MBF in stable coronary artery disease.


Assuntos
Doença da Artéria Coronariana , Reserva Fracionada de Fluxo Miocárdico , Humanos , Doença da Artéria Coronariana/diagnóstico por imagem , Constrição Patológica , Estudos Prospectivos , Isquemia , Tomografia Computadorizada por Raios X , Angiografia Coronária , Perfusão
4.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-990101

RESUMO

Objective:To illustrate the onset of epileptic seizures in children with brain injury admitted in pediatric intensive care unit (PICU), and to explore the risk factors and the correlation between epileptic seizures and the prognosis.Methods:Clinical data of pediatric patients with brain injury who were admitted to PICU of Peking University First Hospital from January 2013 to December 2019, and monitored by video electroencephalography (VEEG) were retrospectively collected, including general demographic information, etiological data, clinical seizures prior to VEEG performing, in-hospital mortality, brain function score, VEEG manifestations, etc.Seizures detected by VEEG were the primary outcome, and prognosis when discharged from PICU was the secondary outcome. Logistic regression was used to analyze the factors associated with seizures and poor outcome. Results:A total of 284 children were included, involving 54.9%(156/284) males.The median age of included children was 1.7(0.5, 5.0) years.Stratified by the cause of disease, 45.1%(128/284) had epilepsy, 26.1%(74/128) had genetic metabolic disease, and 14.4%(41/284) had central nervous system infection.A total of 82.0%(233/284) children had abnormal VEEG background activities, and 59.5%(169/284) had interictal epileptic discharges.Seizures were detected in 106 cases, including 39.6%(42/106) of non-convulsive seizures and 24.5%(26/106) of non-convulsive epileptic states.There were 12.0% (34/284) had poor prognosis at discharge, including 24 patients died in-hospital, and Pediatric Cerebral Performance Category scores were increased in 10 survivors.Multivariate Logistic regression analysis showed that seizures existed before VEEG monitoring and interictal epileptiform discharge were the independent risk factors for seizure.Besides, mental retardation, sepsis related encephalopathy, consciousness abnormality during VEEG, abnormal VEEG background activity, and epileptic status were significantly correlated with the poor prognosis of children with brain injury in PICU. Conclusions:The incidence of electrographic seizure is higher in children with brain injury in PICU, and VEEG monitoring is beneficial to children with brain injury that achieves an early identification of seizures and prediction of prognosis.

5.
J Am Chem Soc ; 143(35): 14253-14260, 2021 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-34459185

RESUMO

Metal halide perovskite quantum dots, with high light-absorption coefficients and tunable electronic properties, have been widely studied as optoelectronic materials, but their applications in photocatalysis are hindered by their insufficient stability because of the oxidation and agglomeration under light, heat, and atmospheric conditions. To address this challenge, herein, we encapsulated CsPbBr3 nanocrystals into a stable iron-based metal-organic framework (MOF) with mesoporous cages (∼5.5 and 4.2 nm) via a sequential deposition route to obtain a perovskite-MOF composite material, CsPbBr3@PCN-333(Fe), in which CsPbBr3 nanocrystals were stabilized from aggregation or leaching by the confinement effect of MOF cages. The monodispersed CsPbBr3 nanocrystals (4-5 nm) within the MOF lattice were directly observed by transmission electron microscopy and corresponding mapping analysis and further confirmed by powder X-ray diffraction, infrared spectroscopy, and N2 adsorption characterizations. Density functional theory calculations further suggested a significant interfacial charge transfer from CsPbBr3 quantum dots to PCN-333(Fe), which is ideal for photocatalysis. The CsPbBr3@PCN-333(Fe) composite exhibited excellent and stable oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) catalytic activities in aprotic systems. Furthermore, CsPbBr3@PCN-333(Fe) composite worked as the synergistic photocathode in the photoassisted Li-O2 battery, where CsPbBr3 and PCN-333(Fe) acted as optical antennas and ORR/OER catalytic sites, respectively. The CsPbBr3@PCN-333(Fe) photocathode showed lower overpotential and better cycling stability compared to CsPbBr3 nanocrystals or PCN-333(Fe), highlighting the synergy between CsPbBr3 and PCN-333(Fe) in the composite.

6.
J Radiosurg SBRT ; 7(3): 189-197, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33898082

RESUMO

PURPOSE/OBJECTIVES: Metastasis-directed therapy with stereotactic body radiotherapy (SBRT) in the setting of oligometastatic disease is a rapidly evolving paradigm given ongoing improvements in systemic therapies and diagnostic modalities. However, SBRT to targets in the abdomen and pelvis is historically associated with concerns about toxicity. The purpose of this study was to evaluate the safety and efficacy of SBRT to the abdomen and pelvis for women with oligometastases from primary gynecological tumors. MATERIALS/METHODS: From our IRB-approved registry, all patients who were treated with SBRT between 2014 and 2020 were identified. Oligometastatic disease was defined as 1 to 5 discrete foci of clinical metastasis radiographically diagnosed by positron emission tomography (PET) and/or computerized tomography (CT) imaging. The primary endpoint was local control at 12 months. Local and distant control rates were estimated using the Kaplan-Meier method. Time intervals for development of local progression and distant progression were calculated based on follow up visits with re-staging imaging. Acute and late toxicity outcomes were determined based on Common Terminology Criteria for Adverse Events (CTCAE) version 5.0. RESULTS: We identified 34 women with 43 treated lesions. Median age was 68 years (range 32-82), and median follow up time was 12 months (range 0.2-54.0). Most common primary tumor sites were ovarian (n=12), uterine (n=11), and cervical (n=7). Median number of previous lines of systemic therapy agents at time of SBRT was 2 (range 0-10). Overall, SBRT was delivered to 1 focus of oligometastasis in 29 cases, 2 foci in 2 cases, 3 foci in 2 cases, and 4 foci in 1 case. All patients were treated comprehensively with SBRT to all sites of oligometastasis. Median prescription dose was 24 Gy (range 18-54 Gy) in 3 fractions (range 3-6) to a median prescription isodose line of 83.5% (range 52-95). Local control by lesion at 12 and 24 months was 92.5% for both time points. Local failure was observed in three treated sites among two patients, two of which were at 11 months in one patient, and the other at 30 months. Systemic control rate was 60.2% at 12 months. Overall survival at 12 and 24 months was 85% and 70.2%, respectively. Acute grade 2 toxicities included nausea (n=3), and there were no grade > 3 acute toxicities. Late grade 1 toxicities included diarrhea (n=1) and fatigue (n=1), and there were no grade > 2 toxicities. CONCLUSION: SBRT to oligometastatic gynecologic malignancies in the abdomen and pelvis is feasible with encouraging preliminary safety and local control outcomes. This approach is associated with excellent local control and low rates of toxicity during our follow-up interval. Further investigations into technique, dose-escalation and utilization are warranted.

7.
J Pharmacol Sci ; 145(1): 115-121, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33357769

RESUMO

As a natural compound isolated from Paeoniae radix, Paeoniflorin (PF) has been shown the antitumor effects in various types of human cancers including glioma, which is one of the serious tumors in central nervous system. Translocator protein 18 KDa (TSPO) has been shown to be relevant to the glioma aetiology. However, the regulation of PF in TSPO and neurosteriods biosynthesis on glioma is still unclear. In the present study, the glioma cell (U87 and U251) were cultured and used to quantify the bindings of PF on TSPO. Results indicated that there was not significant different between IC50 of PF and TSPO ligand PK11195. Moreover, PF exerted the anti-proliferative effects in glioma cell with a dose dependent inhibition from 12.5 to 100 µM in vitro. Consistent with the effects of PK11195, lowered levels on progesterone, allopregnanolone, as well as TSPO mRNA were induced by PF (25 and 50 µM). Furthermore, a xenograft mouse model with U87 cell-derived was significant inhibited by PF treatment, as well as the PK11195 administration. These results demonstrate that PF exerts its antitumor effects associated with the TSPO and neurosteroids biosynthesis in glioma cells could be a promising therapeutic agent for glioma therapy.


Assuntos
Antineoplásicos Fitogênicos , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/genética , Glioma/tratamento farmacológico , Glioma/genética , Glucosídeos/farmacologia , Glucosídeos/uso terapêutico , Monoterpenos/farmacologia , Monoterpenos/uso terapêutico , Fitoterapia , Receptores de GABA/metabolismo , Animais , Linhagem Celular Tumoral , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Glioma/metabolismo , Glioma/patologia , Isoquinolinas/farmacologia , Isoquinolinas/uso terapêutico , Neuroesteroides/metabolismo
8.
Angew Chem Int Ed Engl ; 59(41): 18224-18228, 2020 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-32613736

RESUMO

Intriguing properties and functions are expected to implant into metal-organic layers (MOLs) to achieve tailored pore environments and multiple functionalities owing to the synergies among multiple components. Herein, we demonstrate a facile one-pot synthetic strategy to incorporate multiple functionalities into stable zirconium MOLs via secondary ligand pillaring. Through the combination of Zr6 -BTB (BTB=benzene-1,3,5-tribenzoate) layers and diverse secondary ligands (including ditopic and tetratopic linkers), 31 MOFs with multi-functionalities were systematically prepared. Notably, a metal-phthalocyanine fragment was successfully incorporated into this Zr-MOL system, giving rise to an ideal platform for the selective oxidation of anthracene. The organic functionalization of two-dimensional MOLs can generate tunable porous structures and environments, which may facilitate the excellent catalytic performance of as-synthesized materials.

9.
Front Oncol ; 10: 539, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32373529

RESUMO

Purpose: To assess the optimal planning target volume (PTV) margins for stereotactic body radiotherapy (SBRT) of prostate cancer based on inter- and intra-fractional prostate motion determined from daily image guidance. Methods and Materials: Two hundred and five patients who were enrolled on two prospective studies of SBRT (8 Gy × 5 fractions) for localized prostate cancer treated at a single institution between 2012 and 2017 had complete inter- and intra-fractional shift data available. All patients had scheduled kilovoltage planar imaging during SBRT with rigid registration to intraprostatic fiducials prior to each of four half-arcs delivered per fraction, as well as cone beam CT verification of anatomy prior to each fraction. Inter- and intra- fractional shift data were obtained to estimate the required PTV margins based on the classic van Herk formula. Inter- and intra-fractional motion were compared between patients with and without severe toxicities using the independent two-sample Wilcoxon test. Results: The margins required to account for inter-fractional motion were estimated to be 0.99, 1.52, and 1.45 cm in lateral (LR), longitudinal (SI), and vertical (AP) directions, respectively. The margins required to account for intra-fractional motion were estimated to be 0.19, 0.27, and 0.31 cm in LR, SI and AP directions, respectively. Large intra-fractional shifts were mostly observed in the SI and AP directions, with 2.0 and 5.4% of patients experiencing average intra-fractional motion >3 mm in the SI and AP directions, respectively, compared with none experiencing mean shifts >3 mm in the LR direction. Six patients experienced grade 3 gastrointestinal or genitourinary toxicity. There were no significant differences in mean inter- or intra-fractional motion in any of the cardinal directions compared to patients without severe toxicity (inter-fractional p = 0.46-0.99, intra-fractional p = 0.10-0.84). Conclusion: The inter- and intra-fractional margins estimated from this study are in line with prior reported values. Intra-fractional prostate motion was generally small with larger margins required for the SI and AP directions, notably just slightly exceeding the commonly used 3 mm posterior PTV margin even with realignment between half-arcs. Development of severe toxicity was not significantly associated with the degree of inter- or intra-fractional motion.

10.
J Nanosci Nanotechnol ; 19(11): 7123-7130, 2019 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-31039866

RESUMO

Treatment of high concentration organic wastewater has always been a difficult problem in the field of water purification due to its high cost, low efficiency, long processing cycle and possible second pollution. An overlapped nano-Fe2O3/TiO2@activated carbon fiber membrane composite was successfully prepared by hydrothermal loading method. Nano-rod-like TiO2 and columnar Fe2O3 polyhedrals overlapped and formed a composite coating on the surface of activated carbon fiber membrane. This composite can absorb visible light and successfully remove the high concentration Congo red pollutant (400 mg/L) in 24 h. The enhanced photocatalytic performance should be attributed to the synergistic reaction of nano-Fe2O3 and nano-TiO2, which improves the separation of photo-generated electrons and holes thus enhances the photocatalytic efficiency. This multifunctional fiber membrane is expected to be widely applied in various organic wastewater treatments.

11.
ACS Med Chem Lett ; 10(1): 27-33, 2019 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-30655942

RESUMO

Recent research suggests that KCNQ isoforms, particularly the KCNQ4 and KCNQ5 subtypes expressed in smooth muscle cells, are involved in both establishing and maintaining resting membrane potentials and regulating smooth muscle contractility. Retigabine (RTG) is a first-in-class antiepileptic drug that potentiates neuronal KCNQ potassium channels, but poor subtype selectivity limits its further application as a pharmacological tool. In this study, we improved the subtype specificity of retigabine by altering the N-1/3 substituents and discovered several compounds that show better selectivity for KCNQ4 and KCNQ5 channels. Among these compounds, 10g is highly selective for KCNQ4 and KCNQ5 channels without potentiating KCNQ1 and KCNQ2 channels. These results are an advance in the exploration of small molecule modifiers that selectively activate different KCNQ isoforms. The developed compounds could also serve as new pharmacological tools for elucidating the function of KCNQ channels natively expressed in various tissues.

12.
Biotechnol Bioeng ; 116(4): 805-815, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30537067

RESUMO

Halomonas has been developed as a platform for the next generation industrial biotechnology allowing open and nonsterile growth without microbial contamination under a high-salt concentration and alkali pH. To reduce downstream cost associated with continuous centrifugation and salt containing wastewater treatment, Halomonas campaniensis strain LS21 was engineered to become self-flocculating by knocking out an etf operon encoding two subunits of an electron transferring flavoprotein in the predicted electron transfer chain. Self-flocculation could be attributed to the decrease of the surface charge and increase of the cellular hydrophobicity resulted from deleted etf. A wastewaterless fermentation strategy based on the self-flocculating H. campaniensis was developed for growth and the production of poly-3-hydroxybutyrate (PHB) as an example. Most microbial cells flocculated and precipitated to the bottom of the bioreactor within 1 min after stopping the aeration and agitation. The supernatant can be used again without sterilization or inoculation for the growth of the next batch after collecting the precipitated cell mass. The wastewaterless process was conducted for four runs without generating wastewater. PHB accumulation by the self-flocculent strain was enhanced via promoter and ribosome binding site optimizations, the productivities of cell dry weight and PHB were increased from 0.45 and 0.18 g·L -1 ·hr -1 for the batch process compared to 0.82 and 0.33 g·L -1 ·hr -1 for the wastewaterless continuous process, respectively. This has clearly demonstrated the advantages of the wastewaterless process in that it not only reduces wastewater but also increases cell growth and product formation efficiency in a given period of time.


Assuntos
Fermentação , Halomonas/metabolismo , Hidroxibutiratos/metabolismo , Poliésteres/metabolismo , Águas Residuárias/microbiologia , Reatores Biológicos/microbiologia , Engenharia Celular/métodos , Floculação , Halomonas/genética , Halomonas/crescimento & desenvolvimento , Microbiologia Industrial/métodos , Águas Residuárias/análise , Purificação da Água/métodos
13.
Chinese Journal of Neonatology ; (6): 429-433, 2019.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-823851

RESUMO

Objective To study the video-electroencephalography (vEEG) background activities of very premature infants within the first 7 days after birth.Method The inclusion criteria were gestational age (GA) within 31 weeks and bedside vEEG monitoring within first 7 days of birth.Those with severe cranial ultrasound (CUS) findings,refused treatment,dead and with seizures on vEEG were excluded.The clinical information of included cases were reviewed and the continuity and sleep-wake cycle (SWC) on their EEG background activities were analysed.Result From June 2017 to April 2018,a total of 56 cases were included.Their GA were (29.4 ± 1.6) weeks,and birth weight were (1 306 ± 316) g.A total of 31 cases were diagnosed with asphyxia(1 min Apgar score less than 8),and no one with 5 min Apgar score below 5.Their umbilical artery blood pHs were 7.29 ± 0.07.Their first CUS and the CUS at corrected gestational age (cGA) full term were all within the normal range.The Gesell neurological assessment at cGA 6 months were all within the normal range.As the cGA increased,the continuity of EEG background activities became more continuous as the normal continuous/discontinuous pattern.The 95% confidence interval of max interburst interval was 95 s.The SWC first occurred at GA 26 w,but was immature,then became mature as the cGA increased.Conclusion The EEG background activity analysis of relatively normal very premature infants within first week shows that interburst interval can be longer than the previous report,and the SWC first appear at GA 26 w.

14.
Chinese Journal of Neonatology ; (6): 343-346, 2019.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-753033

RESUMO

Objective To assess the safety and feasibility of video electroencephalographic (VEEG) monitoring in preterm infants and critically ill neonates in neonatal intensive care unit (NICU). Method From December 2017 to June 2018, high risk infants were prospectively enrolled and received VEEG monitoring in our NICU. Their basic information, adverse events and disturbances of any procedure during VEEG monitoring were collected by specially-trained nurses. Result A total of 245 times of VEEG were recorded. The average gestational age (GA) was (32.1 ± 3.6) weeks, the birth weight (BW) was (1879 ± 757) g, the corrected GA (cGA) at VEEG monitoring was (33.8±3.3) weeks, and the average weight at VEEG monitoring was (2008±716) g. The earliest cGA at VEEG monitoring was 25+5 weeks, and the lowest weight at VEEG monitoring was 520 g. The average monitoring duration was (4.9±2.4) h, ranging from 3 to 20 hours. During VEEG monitoring, 80 cases (32.7%) received noninvasive ventilation, 43 cases (17.6%) mechanical ventilation. The adverse events during electrodes placement were oxygen desaturation in 8(3.3%) cases. During VEEG monitoring, local skin erythema were found in 4 cases (1.6%), and electrodes displacement in 2(0.8%) cases. The disturbances of any clinical procedures were reported in 18(7.3%) cases. No severe adverse events such as displacement of endotracheal tube nor events requiring cardiopulmonary resuscitation occurred during VEEG monitoring. Conclusion It is feasible and safe for trained NICU nurses to place electrodes for high risk neonates.

15.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-817851

RESUMO

OBJECTIVE: To study the clinical characteristics of epileptic patients with synchronous occipital and frontopolar spikes phenomenon. METHODS: The clinical data,EEG features of patients with synchronous occipital and frontopolar spikes phenomenon were retrospectively reviewed. RESULTS: Totally 34 male and 21 female patients had synchronous occipital and frontopolar spikes. Ages at the time of recording the synchronous occipital and frontopolar spikes phenomenon ranged from 2 years 6 months to 14 years with the median age of 6 years 6 months. In the total 55 patients,12 patients had contralateral synchronous discharges,12 patients had ipsilateral synchronous,17 patients had bilateral synchronous discharges,7 patients had bilateral synchronous discharges tending to contralateral synchronously,and 7 patients had bilateral synchronous discharges tending to ipsilateral synchronously. Occipital preceded frontopolar discharges in 42 patients. Frontopolar preceded occipital discharges in 3 patients. The phase difference between the occipital and frontopolar spikes could not be distinguished in 10 patients. Based on the etiology and diagnoses,there was Panayiotopoulos syndrome in 33 patients,epilepsy with structural abnormality in 13 patients,secondary epilepsy due to immune encephalitis in 1 patient,epilepsy accompanied by inborn error of metabolism in 2 patients and epilepsy with unknown etiology in 6 patients. CONCLUSION: The synchronous occipital and frontopolar spikes phenomenon usually appears during childhood or develops from other discharge patterns in infancy stage. The synchronous occipital and frontopolar spikes phenomenon can be ipsilateral synchronous or contralateral synchronous discharges. The occipital spikes preceded frontopolar spikes in most patients. The synchronous occipital and frontopolar spikes phenomenon is mostly found in Panayiotopoulos syndrome,but it is also found in epilepsy with different etiologies.

16.
Metab Eng ; 49: 275-286, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30219528

RESUMO

Halomonas bluephagenesis has been developed as a platform strain for the next generation industrial biotechnology (NGIB) with advantages of resistances to microbial contamination and high cell density growth (HCD), especially for production of polyhydroxyalkanoates (PHA) including poly(3-hydroxybutyrate) (PHB), poly(3-hydroxybutyrate-co-4-hydroxybutyrate) (P34HB) and poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV). However, little is known about the mechanism behind PHA accumulation under oxygen limitation. This study for the first time found that H. bluephagenesis utilizes NADH instead of NADPH as a cofactor for PHB production, thus revealing the rare situation of enhanced PHA accumulation under oxygen limitation. To increase NADH/NAD+ ratio for enhanced PHA accumulation under oxygen limitation, an electron transport pathway containing electron transfer flavoprotein subunits α and ß encoded by etf operon was blocked to increase NADH supply, leading to 90% PHB accumulation in the cell dry weight (CDW) of H. bluephagenesis compared with 84% by the wild type. Acetic acid, a cost-effective carbon source, was used together with glucose to balance the redox state and reduce inhibition on pyruvate metabolism, resulting in 22% more CDW and 94% PHB accumulation. The cellular redox state changes induced by the addition of acetic acid increased 3HV ratio in its copolymer PHBV from 4% to 8%, 4HB in its copolymer P34HB from 8% to 12%, respectively, by engineered H. bluephagenesis. The strategy of systematically modulation on the redox potential of H. bluephagenesis led to enhanced PHA accumulation and controllable monomer ratios in PHA copolymers under oxygen limitation, reducing energy consumption and scale-up complexity.


Assuntos
Halomonas/metabolismo , Hidroxibutiratos/metabolismo , Engenharia Metabólica , NAD/metabolismo , Poliésteres/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Halomonas/genética , NAD/genética , Oxigênio/metabolismo
17.
Ying Yong Sheng Tai Xue Bao ; 28(1): 266-272, 2017 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-29749211

RESUMO

The purification mechanisms of plant leaves with atmospheric particles include adsorption, resuspension, rainwater leaching and absorption. However, few studies focused on the resuspension process of atmospheric particles suspending on the surface of leaves, and the correlation between content of adsorbed particles and content of elements in the leaves. Therefore, two common greening tree species, Platanus acerifolia and Magnolia grandiflora, were selected to analyze the atmospheric particles contents on the leaf surface, the leaf mineral element content, and the resuspension ratios. The results showed that the adsorption capacity of P. acerifolia (4.98 g·m-2) was higher than that of M. grandiflora (2.65 g·m-2), which might be connected with rough leaves and dense hairs. The selected 15 elements were all detected by ICP on the leaf surface and in the leaves of two species. In general, the elemental values of the leaf surface were positively related with those in the leaves. However, the two plants showed different selective absorption capacities because positive relation between element adsorption and absorption was only found for Cr, Fe and V for P. ace-rifolia, while such relation was only not found for K, Mn, Si, Ti and Zn for M. grandiflora. The results implied that the absorption was of high selectivity to different elements. Moreover, both increase in wind speed and exposure duration in the wind significantly enhanced resuspension ratios of atmospheric particles. We suggested that resuspension should be taken into account of assessing the relationship between the atmospheric particles deposition and associated plants' function in the future.


Assuntos
Poluentes Atmosféricos , Monitoramento Ambiental , Árvores , Adsorção , Folhas de Planta
19.
ACS Synth Biol ; 5(11): 1264-1274, 2016 11 18.
Artigo em Inglês | MEDLINE | ID: mdl-27238205

RESUMO

5-Aminolevulinic acid (ALA), an important cell metabolic intermediate useful for cancer treatments or plant growth regulator, was produced by recombinant Escherichia coli expressing the codon optimized mitochondrial 5-aminolevulinic acid synthase (EC: 2.3.1.37, hem1) from Saccharomyces cerevisiae controlled via the plasmid encoding T7 expression system with a T7 RNA polymerase. When a more efficient autoinduced expression approach free of IPTG was applied, the recombinant containing antibiotic-free stabilized plasmid was able to produce 3.6 g/L extracellular ALA in shake flask studies under optimized temperature. A recombinant E. coli expressing synthesis pathways of poly-3-hydroxybutyrate (PHB) and ALA resulted in coproduction of 43% PHB in the cell dry weights and 1.6 g/L extracellular ALA, leading to further reduction on ALA cost as two products were harvested both intracellularly and extracellularly. This was the first study on coproduction of extracellular ALA and intracellular PHB for improving bioprocessing efficiency. The cost of ALA production could be further reduced by employing a Halomonas spp. TD01 able to grow and produce ALA and PHB under continuous and unsterile conditions even though ALA had the highest titer of only 0.7 g/L at the present time.


Assuntos
Ácido Aminolevulínico/metabolismo , Escherichia coli/genética , Poliésteres/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/enzimologia , Vias Biossintéticas , Clonagem Molecular , RNA Polimerases Dirigidas por DNA/genética , RNA Polimerases Dirigidas por DNA/metabolismo , Escherichia coli/metabolismo , Halomonas/genética , Halomonas/metabolismo , Hidroxibutiratos/metabolismo , Mitocôndrias/genética , Mitocôndrias/metabolismo , Plasmídeos/genética , Engenharia de Proteínas , Rhodobacter sphaeroides/genética , Rhodobacter sphaeroides/metabolismo , Proteínas Virais/genética , Proteínas Virais/metabolismo
20.
Virol Sin ; 31(3): 219-28, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27105639

RESUMO

Congenital human cytomegalovirus (HCMV) infection is a leading infectious cause of birth defects. Previous studies have reported birth defects with multiple organ maldevelopment in congenital HCMV-infected neonates. Multipotent mesenchymal stromal cells (MSCs) are a group of stem/progenitor cells that are multi-potent and can self-renew, and they play a vital role in multi-organ formation. Whether MSCs are susceptible to HCMV infection is unclear. In this study, MSCs were isolated from Wharton's jelly of the human umbilical cord and identified by their plastic adherence, surface marker pattern, and differentiation capacity. Then, the MSCs were infected with the HCMV Towne strain, and infection status was assessed via determination of viral entry, replication initiation, viral protein expression, and infectious virion release using western blotting, immunofluorescence assays, and plaque forming assays. The results indicate that the isolated MSCs were fully permissive for HCMV infection and provide a preliminary basis for understanding the pathogenesis of HCMV infection in non-nervous system diseases, including multi-organ malformation during fetal development.


Assuntos
Infecções por Citomegalovirus/virologia , Citomegalovirus/fisiologia , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/virologia , Células Cultivadas , Citomegalovirus/genética , Genoma Viral , Humanos , Cordão Umbilical/citologia , Cordão Umbilical/virologia , Ensaio de Placa Viral , Proteínas Virais/biossíntese , Proteínas Virais/genética , Proteínas Virais/metabolismo , Internalização do Vírus , Replicação Viral
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...