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1.
Nature ; 615(7954): 823-829, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36991190

RESUMEN

Neural networks based on memristive devices1-3 have the ability to improve throughput and energy efficiency for machine learning4,5 and artificial intelligence6, especially in edge applications7-21. Because training a neural network model from scratch is costly in terms of hardware resources, time and energy, it is impractical to do it individually on billions of memristive neural networks distributed at the edge. A practical approach would be to download the synaptic weights obtained from the cloud training and program them directly into memristors for the commercialization of edge applications. Some post-tuning in memristor conductance could be done afterwards or during applications to adapt to specific situations. Therefore, in neural network applications, memristors require high-precision programmability to guarantee uniform and accurate performance across a large number of memristive networks22-28. This requires many distinguishable conductance levels on each memristive device, not only laboratory-made devices but also devices fabricated in factories. Analog memristors with many conductance states also benefit other applications, such as neural network training, scientific computing and even 'mortal computing'25,29,30. Here we report 2,048 conductance levels achieved with memristors in fully integrated chips with 256 × 256 memristor arrays monolithically integrated on complementary metal-oxide-semiconductor (CMOS) circuits in a commercial foundry. We have identified the underlying physics that previously limited the number of conductance levels that could be achieved in memristors and developed electrical operation protocols to avoid such limitations. These results provide insights into the fundamental understanding of the microscopic picture of memristive switching as well as approaches to enable high-precision memristors for various applications. Fig. 1 HIGH-PRECISION MEMRISTOR FOR NEUROMORPHIC COMPUTING.: a, Proposed scheme of the large-scale application of memristive neural networks for edge computing. Neural network training is performed in the cloud. The obtained weights are downloaded and accurately programmed into a massive number of memristor arrays distributed at the edge, which imposes high-precision requirements on memristive devices. b, An eight-inch wafer with memristors fabricated by a commercial semiconductor manufacturer. c, High-resolution transmission electron microscopy image of the cross-section view of a memristor. Pt and Ta serve as the bottom electrode (BE) and top electrode (TE), respectively. Scale bars, 1 µm and 100 nm (inset). d, Magnification of the memristor material stack. Scale bar, 5 nm. e, As-programmed (blue) and after-denoising (red) currents of a memristor are read by a constant voltage (0.2 V). The denoising process eliminated the large-amplitude RTN observed in the as-programmed state (see Methods). f, Magnification of three nearest-neighbour states after denoising. The current of each state was read by a constant voltage (0.2 V). No large-amplitude RTN was observed, and all of the states can be clearly distinguished. g, An individual memristor on the chip was tuned into 2,048 resistance levels by high-resolution off-chip driving circuitry, and each resistance level was read by a d.c. voltage sweeping from 0 to 0.2 V. The target resistance was set from 50 µS to 4,144 µS with a 2-µS interval between neighbouring levels. All readings at 0.2 V are less than 1 µS from the target conductance. Bottom inset, magnification of the resistance levels. Top inset, experimental results of an entire 256 × 256 array programmed by its 6-bit on-chip circuitry into 64 32 × 32 blocks, and each block is programmed into one of the 64 conductance levels. Each of the 256 × 256 memristors has been previously switched over one million cycles, demonstrating the high endurance and robustness of the devices.

2.
Int J Syst Evol Microbiol ; 73(11)2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37916707

RESUMEN

Two Gram-stain-negative bacterial strains, S13-6-6 and S13-6-22T, were isolated from sediment sample collected at a water depth of 4 m from Lake Hongze, Jiangsu Province, PR China. The cells of strains S13-6-6 and S13-6-22T were non-spore-forming, aerobic, non-motile and formed orange colonies on R2A agar. Comparative 16S rRNA gene sequence studies revealed a clear affiliation of the two strains with he phylum Bacteroidota, and revealed the highest pairwise sequence similarities with Lacibacter daechungensis H32-4T (97.8 %), Lacibacter cauensis NJ-8T (97.8 %), Lacibacter luteus TTM-7T (97.4 %) and Lacibacter nakdongensis SS2-56T (97.4 %). The results of phylogenetic analysis based on 16S rRNA gene sequences indicated that the strains formed a clear phylogenetic lineage with the genus Lacibacter. The major fatty acids were identified as iso-C15 : 1G, iso-C15 : 0, iso-C17 : 0 3-OH and summed feature 3 (C16 : 1ω7c and/or C16 : 1ω6c) (>10 %), and the respiratory quinone was identified as menaquinone MK-7. The polar lipids consisted of phosphatidylethanolamine, two unidentified aminolipids, an unidentified phospholipid and six unidentified lipids. The genomic DNA G+C content was determined to be 40.2 mol% (HPLC) for strain S13-6-6 and 40.3 % (genome) for strain S13-6-22T. The combined genotypic and phenotypic data indicated that strains S13-6-6 and S13-6-22T represent a novel species of the genus Lacibacter, for which the name Lacibacter sediminis sp. nov. is proposed. The type strain is S13-6-22T (=CGMCC 1.17450T =JCM 35802T).


Asunto(s)
Ácidos Grasos , Fosfolípidos , Ácidos Grasos/química , Filogenia , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , ADN Bacteriano/genética , Composición de Base , Técnicas de Tipificación Bacteriana , Fosfolípidos/análisis , Lagos/microbiología , Vitamina K 2
3.
J Obstet Gynaecol ; 42(6): 2486-2491, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35678767

RESUMEN

This retrospective cross-sectional study was to investigate factors affecting clinical pregnancy in patients who received gonadotropin-releasing hormone agonist luteal phase long protocol (GnRH-a long protocol) and underwent fresh in-vitro fertilisation (IVF)/intracytoplasmic sperm injection (ICSI) embryo transfer cycle. One thousand five hundred and twenty-five patients who received GnRH-a long protocol and underwent fresh IVF/ICSI embryo transfer cycle were enrolled. The clinical pregnancy rate (63.1 vs. 22.4%, p < .05) and live birth rate (53.8 vs. 14.5%, p < .05) were significantly higher while the miscarriage rate (12.5 vs. 35.3%, p < .05) was significantly lower in the two embryo group than those in the one embryo group. The clinical pregnancy rate (48.5 vs. 64.1%, p < .05) and live birth rate (38.4 vs. 55.0%, p < .05) were significantly lower in patients older than 33.5 years than those in younger patients. The clinical pregnancy rate (52 and 60.6 vs. 79.7%, p < .05) and live birth rate (36 and 51.4 vs. 69.6%, p < .05) of the thin and mediate groups were significantly lower than those in the thick group, whereas the ectopic pregnancy rate (11.5 and 1.9 vs. 0%, p < .05) was significantly higher in the thin group than in the mediate and thick group. Multivariate logistic regression analysis showed that age (OR = 0.956, 95% CI [0.931, 0.982], p < .05), number of embryos transferred (OR = 2.491, 95% CI [1.670, 3.715], p < .05) and endometrial thickness on the transplantation day (OR = 1.124, 95% CI [1.067, 1.185], p < .05) were independent factors significantly associated with clinical pregnancy. In conclusion, endometrial thickness (>14.69 mm) on the day of transfer, two cleavage embryos transferred, and female age (≤33.5 years) are independent factors affecting clinical pregnancy outcomes in controlled ovarian hyperstimulation with GnRH-a long protocol for assisted conception. IMPACT STATEMENTWhat is already known on this subject? Fresh embryo transfer cycle with GnRH-a long protocol will result in a higher pregnancy rate in controlled ovarian hyperstimulation cycles.What do the results of this study add? Endometrial thickness on the day of transfer, number of embryos transferred, and female age were independent factors affecting clinical pregnancy outcomes.What are the implications of these findings for clinical practice and/or further research? When performing a fresh IVF/ICSI embryo transfer cycle with GnRH-a long protocol for ovulation induction, the independent affecting factors should be taken into consideration.


Asunto(s)
Hormona Liberadora de Gonadotropina , Síndrome de Hiperestimulación Ovárica , Adulto , Estudios Transversales , Femenino , Fertilización In Vitro/métodos , Humanos , Masculino , Inducción de la Ovulación/métodos , Embarazo , Índice de Embarazo , Estudios Retrospectivos , Semen
4.
Int J Syst Evol Microbiol ; 70(8): 4653-4660, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32672530

RESUMEN

A novel non-phototrophic member of the genus Rhodoferax was obtained from freshwater. The purpose of this study was to analyse the genome of a nonphototrophic strain and propose a new species based on its phylogenetic, genomic, physiological and chemotaxonomic characteristics. The results of phylogenetic analysis based on 16S rRNA gene sequences supports that the strain, designated Gr-4T, has a close relationship to the genus Rhodoferax. The observed average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) values between strain Gr-4T and its closest related strains were 72.3-74.6 % and 21.9-22.8 %, respectively. These values were much lower than the species separation thresholds for ANI or dDDH of 95-96 and 70 %, respectively, and in fact fall in the intergeneric range. Strain Gr-4T does not contain RuBisCO-related genes, but does contain GS/GOGAT pathway-related genes enabling nitrate ammonification. A polyphasic study and a genomic-level investigation were done to establish the taxonomic status of strain Gr-4T. Based on the phylogenetic, genomic and physiological differences, it is proposed that the isolate be classified to the genus Rhodoferax as Rhodoferax aquaticus sp. nov. with isolate Gr-4T (=KCTC 32394T=JCM 19166T) as the type strain.


Asunto(s)
Comamonadaceae/clasificación , Agua Dulce/microbiología , Filogenia , Técnicas de Tipificación Bacteriana , Composición de Base , Comamonadaceae/aislamiento & purificación , ADN Bacteriano/genética , Ácidos Grasos/química , Genes Bacterianos , Hibridación de Ácido Nucleico , ARN Ribosómico 16S/genética , República de Corea , Análisis de Secuencia de ADN
5.
Antonie Van Leeuwenhoek ; 113(3): 365-375, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31691050

RESUMEN

A novel Gram-stain-positive bacterial strain, CHu50b-6-2T, was isolated from a 67-cm-long sediment core collected from the Daechung Reservoir at a water depth of 17 m, Daejeon, Republic of Korea. The cells of strain CHu50b-6-2T were aerobic non-motile and formed yellow colonies on R2A agar. The phylogenetic analysis based on 16S rRNA gene sequencing indicated that the strain formed a separate lineage within the family Microbacteriaceae, exhibiting 98.0%, 97.7% and 97.6% 16S rRNA gene sequence similarities to Glaciihabitans tibetensis KCTC 29148T, Frigoribacterium faeni KACC 20509T and Lysinibacter cavernae DSM 27960T, respectively. The phylogenetic trees revealed that strain CHu50b-6-2T did not show a clear affiliation to any genus within the family Microbacteriaceae. The chemotaxonomic results showed B1α type peptidoglacan containg 2, 4-diaminobutyric acid (DAB) as the diagnostic diamino acid, MK-10 as the predominant respiratory menaquinone, diphosphatidylglycerol, phosphatidylglycerol, and an unidentified glycolipid as the major polar lipids, anteiso-C15:0, iso-C16:0, and anteiso-C17:0 as the major fatty acids, and a DNA G + C content of 67.3 mol%. The combined genotypic and phenotypic data showed that strain CHu50b-6-2T could be distinguished from all genera within the family Microbacteriaceae and represents a novel genus, Lacisediminihabitans gen. nov., with the name Lacisediminihabitans profunda sp. nov., in the family Microbacteriaceae. The type strain is CHu50b-6-2T (= KCTC 49081T = JCM 32673T).


Asunto(s)
Agua Dulce/microbiología , Sedimentos Geológicos/microbiología , Mycobacteriaceae/clasificación , Mycobacteriaceae/aislamiento & purificación , Microbiología del Agua , Genoma Viral , Genómica/métodos , Mycobacteriaceae/genética , Fenotipo , Filogenia , ARN Ribosómico 16S/genética
6.
Science ; 383(6685): 903-910, 2024 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-38386733

RESUMEN

In-memory computing represents an effective method for modeling complex physical systems that are typically challenging for conventional computing architectures but has been hindered by issues such as reading noise and writing variability that restrict scalability, accuracy, and precision in high-performance computations. We propose and demonstrate a circuit architecture and programming protocol that converts the analog computing result to digital at the last step and enables low-precision analog devices to perform high-precision computing. We use a weighted sum of multiple devices to represent one number, in which subsequently programmed devices are used to compensate for preceding programming errors. With a memristor system-on-chip, we experimentally demonstrate high-precision solutions for multiple scientific computing tasks while maintaining a substantial power efficiency advantage over conventional digital approaches.

7.
Stem Cells Dev ; 32(9-10): 213-224, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36721381

RESUMEN

Adult neural stem cells (NSCs) are restricted to the two neurogenic regions of the mammalian brain, where they self-renew and generate progenies of multiple lineages, including neurons, astrocytes, and oligodendrocytes. Single-cell RNA sequencing technology, which reconstructs high-resolution transcriptional landscapes, provides valuable insights into cellular heterogeneity and developmental dynamics. In this review, we overviewed recent progress in the single-cell analyses of both conventional and unconventional NSCs. We discussed the heterogeneity among the stem cell pool and characterized the transcriptional alterations in aging and brain tumors. A comprehensive understanding of NSCs in physiological and pathological settings will provide insights for the rejuvenation of the aged brain and restoration of normal brain function in multiple neurological disorders.


Asunto(s)
Células Madre Adultas , Células-Madre Neurales , Animales , Diferenciación Celular , Células-Madre Neurales/fisiología , Neuronas/fisiología , Neurogénesis , Encéfalo , Células Madre Adultas/fisiología , Mamíferos
8.
Front Microbiol ; 14: 1295854, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38075887

RESUMEN

A free-living Bradyrhizobium strain isolated from a contaminated sediment sample collected at a water depth of 4 m from the Hongze Lake in China was characterized. Phylogenetic investigation of the 16S rRNA gene, concatenated housekeeping gene sequences, and phylogenomic analysis placed this strain in a lineage distinct from all previously described Bradyrhizobium species. The sequence similarities of the concatenated housekeeping genes support its distinctiveness with the type strains of the named species. The complete genome of strain S12-14-2 consists of a single chromosome of size 7.3M. The strain lacks both a symbiosis island and important nodulation genes. Based on the data presented here, the strain represents a new species, for which the name Bradyrhizobium roseus sp. nov. is proposed for the type strain S12-14-2T. Several functional differences between the isolate and other published genomes indicate that the genus Bradyrhizobium is extremely heterogeneous and has functions within the community, such as non-symbiotic nitrogen fixation. Functional denitrification and nitrogen fixation genes were identified on the genomes of strain S12-14-2T. Genes encoding proteins for sulfur oxidation, sulfonate transport, phosphonate degradation, and phosphonate production were also identified. Lastly, the B. roseus genome contained genes encoding ribulose 1,5-bisphosphate carboxylase/oxygenase, a trait that presumably enables autotrophic flexibility under varying environmental conditions. This study provides insights into the dynamics of a genome that could enhance our understanding of the metabolism and evolutionary characteristics of the genus Bradyrhizobium and a new genetic framework for future research.

9.
Int J Neuropsychopharmacol ; 15(6): 749-66, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21733236

RESUMEN

ß-amyloid (Aß) peptides play an important role in cognition deficits, neuroinflammation, and apoptosis observed in Alzheimer's disease (AD). Activation of cyclic AMP (cAMP) signalling enhances memory and inhibits inflammatory and apoptotic responses. However, it is not known whether inhibition of phosphodiesterase-4 (PDE4), a critical controller of intracellular cAMP concentrations, affects AD-associated neuroinflammatory and apoptotic responses and whether these responses contribute to deficits of memory mediated by cAMP signalling. We addressed these issues using memory tests and neurochemical measures. Specifically, rats microinfused with aggregated Aß25-35 (10 µg/side) into bilateral CA1 subregions displayed deficits in learning ability and memory, as evidenced by decreases in escape latency during acquisition trials and exploratory activities in the probe trial in the water-maze task and 24-h retention in the passive avoidance test. These effects were reversed by rolipram (0.1, 0.25 and 0.5 mg/kg.d i.p.), a prototypic PDE4 inhibitor, in a dose-dependent manner. Interestingly, Aß25-35-treated rats also displayed decreases in expression of phosphorylated cAMP response-element binding protein (pCREB) and Bcl-2, but increases in expression of NF-κB p65 and Bax in the hippocampus; these effects were also reversed by rolipram in a dose-dependent manner. Similar neurochemical results were observed by replacing Aß25-35 with Aß1-42, a full-length amyloid peptide that quickly forms toxic oligomers. These results suggest that PDE4 inhibitors such as rolipram may reverse Aß-induced memory deficits at least in part via the attenuation of neuronal inflammation and apoptosis mediated by cAMP/CREB signalling. PDE4 could be a target for treatment of memory loss associated with AD.


Asunto(s)
Apoptosis/efectos de los fármacos , Trastornos del Conocimiento/tratamiento farmacológico , Encefalitis/tratamiento farmacológico , Inhibidores de Fosfodiesterasa 4/uso terapéutico , Rolipram/uso terapéutico , Péptidos beta-Amiloides/toxicidad , Animales , Reacción de Prevención/efectos de los fármacos , Proteína de Unión a CREB/genética , Proteína de Unión a CREB/metabolismo , Trastornos del Conocimiento/inducido químicamente , Adaptación a la Oscuridad/efectos de los fármacos , Modelos Animales de Enfermedad , Relación Dosis-Respuesta a Droga , Encefalitis/inducido químicamente , Regulación de la Expresión Génica/efectos de los fármacos , Masculino , Aprendizaje por Laberinto/efectos de los fármacos , FN-kappa B/genética , FN-kappa B/metabolismo , Pruebas Neuropsicológicas , Fragmentos de Péptidos/toxicidad , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Ratas , Ratas Sprague-Dawley , Proteína X Asociada a bcl-2/metabolismo
10.
Metab Brain Dis ; 27(4): 495-505, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22843383

RESUMEN

The calcium sensitizers levosimendan and piperphentonamine hydrochloride (PPTA) are used as cardiovascular drugs for treatment of heart failure. Given that levosimendan has been reported to exhibit a neuroprotective profile in a model of traumatic brain injury, it was interesting to know whether PPTA, a new calcium sensitizer recently developed in China, exerts a similar effect. The objective of this study was to determine whether PPTA exhibited neuroprotective effects and whether these properties were associated with memory. Four-vessel occlusion (4-VO) was used to induce global cerebral ischemia/reperfusion injury in rats treated with or without PPTA (5, 10 mg/kg, i.p., 2 h after the onset of reperfusion and then once a day for 15 consecutive days). Memory was measured using the step-through passive avoidance test. Neurochemical changes were examined in rat PC12 cells treated with oxygen-glucose deprivation (OGD) for 4 h followed by reoxygenation (OGD-R) for 24 h, in the absence or presence of PPTA. In vehicle-treated animals, 4-VO for 10 min produced memory deficits, as demonstrated by decreased retention in step-through passive avoidance, and massive neuron loss in the hippocampal CA1 subregion. These effects were attenuated by PPTA. The results were consistent with those observed in PC12 cells. PPTA treatment increased cell viability, as indicated by MTT assay, inhibited apoptosis, and decreased extracellular lactate dehydrogenase levels in Na(2)S(2)O(4)-treated PC12 cells. These results provide novel demonstration for the ability of PPTA to attenuate cerebral ischemia-induced memory deficits via neuroprotection in the hippocampus. The neuroprotective effect of PPTA appears to be associated with its anti-apoptotic activity. PPTA has the therapeutic potential for ischemic stroke.


Asunto(s)
3,4-Metilenodioxianfetamina/análogos & derivados , Apoptosis/efectos de los fármacos , Isquemia Encefálica/tratamiento farmacológico , Isquemia Encefálica/psicología , Trastornos de la Memoria/prevención & control , Trastornos de la Memoria/psicología , Fármacos Neuroprotectores/uso terapéutico , 3,4-Metilenodioxianfetamina/uso terapéutico , Animales , Reacción de Prevención/efectos de los fármacos , Región CA1 Hipocampal/citología , Región CA1 Hipocampal/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Glucosa/deficiencia , Hipoxia Encefálica/complicaciones , Hipoxia Encefálica/psicología , L-Lactato Deshidrogenasa/metabolismo , Masculino , Trastornos de la Memoria/etiología , Neuronas/efectos de los fármacos , Células PC12 , Ratas , Ratas Sprague-Dawley , Reacción en Cadena en Tiempo Real de la Polimerasa
11.
Medicine (Baltimore) ; 101(35): e30428, 2022 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-36107580

RESUMEN

INTRODUCTION: Hypermature cataract is a form of late-stage cataract progression that can lead to a variety of complications. Spontaneous capsular rupture with lens nucleus displacement in hypermature cataracts has rarely been reported. We describe 2 cases of spontaneous dislocation of the lens nucleus in a hypermature cataract and perform a review of the literature on this complication. PATIENT CONCERNS: We report 2 rural men aged 50 and 76 years with deteriorating vision. DIAGNOSIS: The final diagnosis was senile hypermature cataract with dislocation of the lens nucleus in both patients and secondary glaucoma for the second patient. INTERVENTIONS AND OUTCOMES: During admission, both patients complained of deteriorating vision. Slit-lamp examination showed lens nucleus dislocation into the anterior chamber. The 50-year-old patient exhibited a residual lens capsule and a turbid cortex, with a normal anterior chamber and intraocular pressure. The 76-year-old patient presented a shrunken and ruptured capsule and no cortex in the pupillary area, mild inflammation in the anterior chamber, and high intraocular pressure. Both patients underwent intracapsular cataract extraction combined with anterior vitrectomy and achieved good postoperative recovery. CONCLUSION: Lens nucleus dislocation in hypermature cataracts can be seen in clinical practice, particularly in underdeveloped areas. Early recognition and surgery can improve vision.


Asunto(s)
Extracción de Catarata , Catarata , Glaucoma , Luxaciones Articulares , Cápsula del Cristalino , Subluxación del Cristalino , Anciano , Cámara Anterior , Catarata/complicaciones , Catarata/etiología , Extracción de Catarata/efectos adversos , Glaucoma/cirugía , Humanos , Luxaciones Articulares/cirugía , Subluxación del Cristalino/diagnóstico , Subluxación del Cristalino/etiología , Subluxación del Cristalino/cirugía , Masculino , Persona de Mediana Edad , Rotura Espontánea/cirugía
12.
Syst Appl Microbiol ; 45(5): 126353, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-36030678

RESUMEN

Three bacterial strains isolated from a sediment sample collected at a water depth of 4 m from the Huaihe River in China were characterized. Phylogenetic investigation of the 16S rRNA gene and concatenated housekeeping gene sequences assigned the three novel strains in a highly supported lineage distinct from the published Bradyrhizobium species. The sequence similarities of the concatenated housekeeping genes of the three novel strains support their distinctiveness with the type strains of named species. Average nucleotide identity values of the genome sequences (79.9-82.5%) were below the threshold value of 95-96% for bacterial species circumscription. Close relatives to the novel strains are Bradyrhizobium erythrophlei, Bradyrhizobium jicamae, Bradyrhizobium lablabi, Bradyrhizobium mercantei, Bradyrhizobium elkanii and Bradyrhizobium japonicum. The complete genomes of strains S2-20-1T, S2-11-2 and S2-11-4 consist of single chromosomes of size 5.55, 5.45 and 5.47 Mb, respectively. These strains lack a symbiosis island, key nodulation and photosystem genes. Based on the data presented here, the three strains represent a novel species for which the name Bradyrhizobium sediminis sp. nov. is proposed for S2-20-1T as the type strain. Those three strains are proposed as novel species in free-living Bradyrhizobium isolates with the smallest genomes so far within the genus Bradyrhizobium. A number of functional differences between the three isolates and other published genomes indicate that the genus Bradyrhizobium is extremely heterogeneous and has roles within the community including non-symbiotic nitrogen fixation.


Asunto(s)
Bradyrhizobium , Técnicas de Tipificación Bacteriana , Composición de Base , ADN Bacteriano/genética , Agua Dulce , Genes Bacterianos/genética , Genómica , Nitrógeno , Fijación del Nitrógeno/genética , Nucleótidos , Filogenia , ARN Ribosómico 16S/genética , Nódulos de las Raíces de las Plantas/microbiología , Análisis de Secuencia de ADN , Simbiosis/genética , Agua
13.
Front Endocrinol (Lausanne) ; 13: 915923, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36157446

RESUMEN

Objective: The aim of this study is to investigate the optimal estradiol (E2) level on the day of gonadotropin-releasing hormone antagonist (GnRH-ant) initiation to maximize the clinical pregnancy rate (CPR) after fresh embryo transfer among patients with simple tubal factor infertility. Methods: A retrospective cohort study was conducted in the Reproductive Medicine Center, the Second Hospital of Hebei Medical University. A total of 1,493 IVF-ET cycles of patients diagnosed with single tubal factor infertility from August 2016 to August 2021 were included and equally allocated into five distinct groups according to the quintile serum E2 levels on the day of GnRH-ant initiation. The five groups had similar baseline data except for antral follicle count. Results: The serum E 2 level on GnRH-ant initiation day was determined as an independent predictor of clinical pregnancy after adjusting for confounding factors such as age, infertility duration, body mass index, cycle number, antral follicle count, and the number of transferred embryos. Through smooth curve fitting, we found that, with the increase of serum E2 levels on the day of GnRH-ant initiation, CPR showed a trend of slight increase and then slight decrease. The maximal CPR was achieved when the serum E2 level on GnRH-ant initiation day was 498 pg/ml. When E2 was less than 498 pg/ml, the odds ratio (OR) of clinical pregnancy was 1.05 (95% CI: 1.00, 1.11, P = 0.0583). When E2 was greater than 498 pg/ml, the OR of clinical pregnancy was 0.97 (95% CI: 0.95, 0.98, P = 0.0003). Furthermore, CPR remained high when E2 was 436.8-658.6 pg/ml but declined significantly by more than 40% when E2 was ≥ 894.4 pg/ml (P < 0.05). Conclusions: The serum E2 level should be considered as an adjuvant parameter for GnRH-ant initiation. The best E2 value was 498 pg/ml, and GnRH-ant administration could be recommended to initiate when serum E2 was 436.8-658.6 pg/ml. If GnRH-ant was initiated when serum E2 was above 894.4 pg/ml, then the CPR after fresh embryo transfer may decline dramatically, and thus, cancellation of fresh embryo transfer and earlier initiation of GnRH-ant in future cycles should be considered.


Asunto(s)
Fertilización In Vitro , Infertilidad , Estradiol , Femenino , Hormona Liberadora de Gonadotropina , Antagonistas de Hormonas/uso terapéutico , Humanos , Embarazo , Estudios Retrospectivos
14.
Mol Vis ; 17: 1449-56, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21677793

RESUMEN

PURPOSE: To investigate the genotype and phenotype of juvenile-onset open angle glaucoma (JOAG) in a Chinese family (PN pedigree). METHODS: Each family member was comprehensively examined by an experienced ophthalmologist. The clinical characteristics of the family patients with JOAG were documented. Blood samples were obtained from 22 available participants from the PN pedigree. Linkage analysis was performed to identify the possible chromosome loci. The presence of gene mutation was ascertained by polymerase chain reaction amplification and subsequent direct sequencing. RESULTS: The affected members in the PN pedigree are characterized by early age of onset (mean age at diagnosis is 17 years old), severe clinical presentations, high intraocular pressure (mean IOP of 34.18±2.97 mmHg), and poor response to pharmacological treatment (87.5% of the patients required filtering surgery). The region on chromosome 1 between D1S3464 and D1S1619 was identified in this pedigree by linkage analysis. A Pro370Leu myocilin mutation resulting from a heterozygous C→T transition at the 1,109th nucleotide in exon 3 was detected by gene sequencing. The Pro370Leu mutation co-segregated among all affected individuals of PN pedigree. CONCLUSIONS: The GLC1A Pro370Leu mutation is firmly correlated with a severe POAG phenotype. These data provide clues for the severe disease-causing nature of the Pro370Leu allele. Gene screening may be a useful method for pre-symptom diagnosis and a forewarning to detect the at-risk individuals in familial open-angle glaucoma patients, especially in pedigrees of early-onset.


Asunto(s)
Pueblo Asiatico/genética , Proteínas del Citoesqueleto/genética , Proteínas del Ojo/genética , Estudios de Asociación Genética , Glaucoma de Ángulo Abierto/genética , Glicoproteínas/genética , Hipertensión Ocular/genética , Adolescente , Adulto , Edad de Inicio , Secuencia de Bases , Niño , Cromosomas Humanos Par 1/química , Femenino , Ligamiento Genético , Sitios Genéticos , Pruebas Genéticas , Genotipo , Glaucoma de Ángulo Abierto/complicaciones , Glaucoma de Ángulo Abierto/diagnóstico , Glaucoma de Ángulo Abierto/cirugía , Heterocigoto , Humanos , Masculino , Datos de Secuencia Molecular , Mutación , Hipertensión Ocular/complicaciones , Hipertensión Ocular/diagnóstico , Linaje , Fenotipo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Análisis de Secuencia de ADN , Tomografía de Coherencia Óptica , Agudeza Visual
15.
Mol Vis ; 17: 2495-506, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21976960

RESUMEN

PURPOSE: To investigate the efficacy, safety, and mechanisms of Sirolimus sustained delivery film on prevention of scar formation in a rabbit model of glaucoma filtration surgery. METHODS: Sixty-four New Zealand white rabbits who underwent trabeculectomy in the right eye were randomly allocated to one of the four treatment regimens: Sirolimus sustained delivery film treatment group (Group A), or drug-free film treatment group (Group B), or 30 ng/ml Sirolimus-soaked sponge treatment group (Group C), or no adjunctive treatment group (Group D), and each group consists of 16 rabbits. Intraocular pressure (IOP), morphologic changes of bleb, anterior chamber flare, and corneal endothelial cell count and complications were evaluated over a 28-day period follow-up time. Aqueous humor samples were gathered from Group A, and the concentration of Sirolimus was measured regularly post-operation. Rabbits were sacrificed on the 7th, 14th, and 28th day post-operation separately, and the fibroblast hypertrophy, infiltration of inflammatory, and proliferation of new collagen fiber formation in each group were evaluated with HE and Masson staining. Proliferative cell nuclear antigen (PCNA) and fibroblast apoptosis were evaluated by immunohistochemistry and terminal deoxynucleotidyl transferasemediated dUTP nick end labeling (TUNEL) assay at the 28th day post-operation. RESULTS: Both Sirolimus sustained delivery film (Group A) and Sirolimus alone (Group C) were well tolerated in this model, and significantly prolonged bleb survival compared with no drug treatment group (Group B and D; p<0.001). Group A had the longest bleb survival time in comparison with other groups (p<0.001). There were significant differences in IOP readings between Group A and other groups at the last follow-up (p<0.05). The concentration of Group A maintained stable for over 2 weeks, drops from (10.56 ±0.05) ng/ml at day 3 to (7.74 ±0.05) ng/ml at day 14. The number of corneal endothelial cells of Group A was not statistically significant between pre and post-operation. Histologic examination demonstrated that eyes treated with Sirolimus, especially the Sirolimus sustained delivery film, showed an obvious reduction in subconjunctival fibroblast scar tissue formation compared with no drug treatment groups, and had minimal evidence of inflammatory cell infiltration and new collagen deposition in the subconjunctiva. Immunohistochemistry assay showed that PCNA-expression was lower in the Group A (16.25±3.24%) compared to other groups (p<0.01). TUNEL assay showed a significant increase in the number of apoptotic fibroblasts around the surgical area in Group A and Group C (9.75±1.71% and 8.50±1.92%) compared to the Group B and D (p<0.01). CONCLUSIONS: Sirolimus drug sustained delivery film can inhibit inflammatory cell activity, impede fibroblast proliferation activity, and induce fibroblast apoptosis in the filtration surgery sites in rabbit. The results indicate a safe and effective treatment strategy in anti-scaring treatment in glaucoma surgery.


Asunto(s)
Apoptosis/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Cicatriz/prevención & control , Ojo/patología , Fibroblastos/efectos de los fármacos , Cirugía Filtrante , Glaucoma/tratamiento farmacológico , Sirolimus , Animales , Antibacterianos/farmacocinética , Antibacterianos/uso terapéutico , Humor Acuoso/química , Vesícula/metabolismo , Cicatriz/tratamiento farmacológico , Cicatriz/patología , Vías de Administración de Medicamentos , Esquema de Medicación , Sistemas de Liberación de Medicamentos/métodos , Células Endoteliales/citología , Células Endoteliales/efectos de los fármacos , Células Endoteliales/metabolismo , Ojo/efectos de los fármacos , Ojo/metabolismo , Femenino , Fibroblastos/citología , Glaucoma/metabolismo , Glaucoma/patología , Glaucoma/cirugía , Presión Intraocular , Antígeno Nuclear de Célula en Proliferación/análisis , Conejos , Sirolimus/farmacocinética , Sirolimus/uso terapéutico , Tonometría Ocular , Trabeculectomía
16.
Zhonghua Yan Ke Za Zhi ; 47(10): 893-7, 2011 Oct.
Artículo en Zh | MEDLINE | ID: mdl-22321498

RESUMEN

OBJECTIVE: To evaluate the efficacy and safety of FP-7 Ahmed glaucoma valves (AGV) implantation in neurovascular glaucoma (NVG) as the first choice of surgery. METHODS: This retrospective, comparative case series study collected a total of 36 eyes of 36 patients with neurovascular glaucoma who underwent AGV implantation in Zhongshan Ophthalmic Center from January 2009 to June 2010. Change of intraocular pressure (IOP), the best corrected visual acuity, numbers of anti-glaucoma medication, success rate and postoperative complications were followed up at day 1, week 1, month 1, and every 3 months after surgery. Complete success of surgery was rated as reduction of IOP ≥ 30% without medication and those who failed to meet criteria was rated as partial success. Data were analyzed by paired Student t-test for IOP, rank sum test for paired non-parametric numbers of medication, and repeated measures analysis of variance for comparison of IOP between different time points using SPSS 13.0. RESULTS: Compared with pre-operation, IOP was significant (F = 9.26, P < 0.05) decreased after surgery with FP-7 AGV implantation (39.5 ± 9.7) mm Hg (1 mm Hg = 0.133 kPa) vs (9.2 ± 8.9), (11.8 ± 3.8), (13.7 ± 4.8), (16.9 ± 5.3), (16.9 ± 6.8) mm Hg at day 1, week 1, month 1, month 3 and the last following-up of post-operation, respectively. The numbers of anti-glaucoma medication were significantly (Z = 6.764, P < 0.05) reduced from 4.0 (1-6) of pre-operation to 1.0 (1-3) of post-operation. At the last following up, the complete success rate after FP-7 AGV implantation was 80.6%, and qualified success rate was 91.7%. The postoperative complications including occlusion of the drainage tube, exposure of the drainage tube, shallow anterior chamber and encapsulated cystic blebs around the plate were controlled with additional treatment. CONCLUSIONS: The clinical outcome indicated that the implantation of FP-7 AGV has a stable IOP lowering effect and fewer complications, which can be considered as one of the first choices for management of NVG.


Asunto(s)
Implantes de Drenaje de Glaucoma , Glaucoma Neovascular/cirugía , Implantación de Prótesis/métodos , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Resultado del Tratamiento , Adulto Joven
17.
Front Endocrinol (Lausanne) ; 12: 578783, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34079517

RESUMEN

Objective: To investigate the factors that influence luteal phase short-acting gonadotropin-releasing hormone agonist (GnRH-a) long protocol and GnRH-antagonist (GnRH-ant) protocol on pregnancy outcome and quantify the influence. About the statistical analysis, it is not correct for the number of gravidities. Methods: Infertile patients (n = 4,631) with fresh in-vitro fertilization/intracytoplasmic sperm injection (IVF/ICSI) and embryo transfer were divided into GnRH-a long protocol (n =3,104) and GnRH-ant (n =1,527) protocol groups and subgroups G1 (EMT ≤7mm), G2 (7 mm 10 mm) according to EMT on the trigger day. The data were analyzed. Results: The GnRH-ant and the GnRH-a long protocols had comparable clinical outcomes in the clinical pregnancy, live birth, and miscarriage rate after propensity score matching. In the medium endometrial thickness of 7-10 mm, the clinical pregnancy rate (61.81 vs 55.58%, P < 0.05) and miscarriage rate (19.43 vs 12.83%, P < 0.05) of the GnRH-ant regime were significantly higher than those of the GnRH-a regime. The EMT threshold for clinical pregnancy rate in the GnRH-ant group was 12 mm, with the maximal clinical pregnancy rate of less than 75% and the maximal live birth rate of 70%. In the GnRH-a long protocol, the optimal range of EMT was >10 mm for the clinical pregnancy rate and >9.5 mm for the live birth rate for favorable clinical outcomes, and the clinical pregnancy and live birth rates increased linearly with increase of EMT. In the GnRH-ant protocol, the EMT thresholds were 9-6 mm for the clinical pregnancy rate and 9.5-15.5 mm for the live birth rate. Conclusions: The GnRH-ant protocol has better clinical pregnancy outcomes when the endometrial thickness is in the medium thickness range of 7-10 mm. The optimal threshold interval for better clinical pregnancy outcomes of the GnRH-ant protocol is significantly narrower than that of the GnRH-a protocol. When the endometrial thickness exceeds 12 mm, the clinical pregnancy rate and live birth rate of the GnRH-ant protocol show a significant downward trend, probably indicating some negative effects of GnRH-ant on the endometrial receptivity to cause a decrease of the clinical pregnancy rate and live birth rate if the endometrial thickness exceeds 12 mm.


Asunto(s)
Endometrio/patología , Fármacos para la Fertilidad Femenina/uso terapéutico , Infertilidad/tratamiento farmacológico , Fase Luteínica/efectos de los fármacos , Adulto , Tasa de Natalidad , China/epidemiología , Endometrio/efectos de los fármacos , Femenino , Fármacos para la Fertilidad Femenina/farmacología , Fertilización In Vitro/métodos , Hormona Liberadora de Gonadotropina/agonistas , Hormona Liberadora de Gonadotropina/antagonistas & inhibidores , Antagonistas de Hormonas/uso terapéutico , Humanos , Recién Nacido , Infertilidad/epidemiología , Infertilidad/patología , Infertilidad/fisiopatología , Fase Luteínica/fisiología , Tamaño de los Órganos/fisiología , Inducción de la Ovulación/métodos , Embarazo , Resultado del Embarazo/epidemiología , Índice de Embarazo , Estudios Retrospectivos , Resultado del Tratamiento , Adulto Joven
18.
Mol Vis ; 16: 61-71, 2010 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-20090922

RESUMEN

PURPOSE: Patients reproduce symptoms of primary open-angle glaucoma (POAG) when treated with glucocorticoids (GCs) topically on the eyes. Here we investigated the effects of GCs on junctional protein expression and cytoskeleton organization in primary human trabecular meshwork (TM) cultures to understand the molecular pathologies of POAG. METHODS: Human TM cells from POAG (GTM) and age-matched nondiseased (NTM) individuals were obtained by standard surgical trabeculectomy. Some of the cultures were treated with dexamethasone (DEX), a synthetic GC, at 1-5 x 10(-7) mol/l for 1-7 days. The expression levels of zonula occluden-1 (ZO-1) and connexin43 (Cx43) in TM cells with or without DEX treatment were measured using reverse transcription (RT)-PCR, immunocytochemistry, and western blot analysis. RESULTS: mRNA and proteins of ZO-1 and Cx43 were found in both NTM and GTM cells. ZO-1 and Cx43 were located on the plasma membrane, especially along the border of adjacent cells. ZO-1 had no marked changes in localization in NTM and GTM cells after treatment with 10(-7) mol/l DEX for 48 h, whereas Cx43 appeared to increase in the cytoplasm. mRNA of two ZO-1 isoforms, alpha+ and alpha-, were present in TM cells, and the former was expressed less than the latter. Only ZO-1 alpha- isoform protein was expressed in NTM cells, whereas proteins of both isoforms were found in GTM cells. DEX increased the protein levels of ZO-1 and Cx43 in both NTM and GTM cells. DEX also altered the F-actin architecture and promoted cross-linked actin network formation, the effects of which were more pronounced in GTM cells. CONCLUSIONS: Our findings not only provide molecular insights to the pathogenesis of GC-induced glaucoma but also suggest that junctional proteins ZO-1 and Cx43 as well as F-actin are targets for developing new modalities in glaucoma therapy.


Asunto(s)
Citoesqueleto/efectos de los fármacos , Citoesqueleto/metabolismo , Dexametasona/farmacología , Uniones Intercelulares/efectos de los fármacos , Uniones Intercelulares/patología , Malla Trabecular/efectos de los fármacos , Malla Trabecular/patología , Actinas/metabolismo , Adolescente , Adulto , Recuento de Células , Forma de la Célula/efectos de los fármacos , Células Cultivadas , Conexina 43/genética , Conexina 43/metabolismo , Reactivos de Enlaces Cruzados/farmacología , Regulación de la Expresión Génica/efectos de los fármacos , Glaucoma de Ángulo Abierto/metabolismo , Glaucoma de Ángulo Abierto/patología , Humanos , Masculino , Proteínas de la Membrana/genética , Proteínas de la Membrana/metabolismo , Persona de Mediana Edad , Fosfoproteínas/genética , Fosfoproteínas/metabolismo , Malla Trabecular/metabolismo , Adulto Joven , Proteína de la Zonula Occludens-1
19.
Zhonghua Yan Ke Za Zhi ; 46(6): 499-502, 2010 Jun.
Artículo en Zh | MEDLINE | ID: mdl-21055193

RESUMEN

OBJECTIVE: To evaluate clinical outcomes of non-penetrating trabecular surgery (NPTS) and trabeculectomy surgery (TS) in the treatment of primary open angle glaucoma (POAG). METHODS: It was a case-control study. A total of 63 patients (63 eyes) with POAG were observed retrospectively. Thirty one eyes and 32 eyes underwent NPTS and TS, respectively. Intraocular pressure (IOP), filtration bleb, visual field and post-operative complications were observed for 6-60 months. The CMH χ(2) test was used to analyse the difference of them. RESULTS: After operation, the IOP in the NPTS group were from (13.87 ± 4.88) mm Hg (1 mm Hg = 0.133 kPa) to (24.01 ± 6.55) mm Hg, the IOP in the TS group were from (11.90 ± 4.92) mm Hg to (19.10 ± 7.43) mm Hg. The IOP in the NPTS group was significantly higher than that in the TS group (F = 5.137, P < 0.05). The ratio of sustained filtration bleb of NPTS group after surgery was 25/31 (80.6%), while 6/31 were flat filtration bleb. There were statistically significant difference in the rate of disappearance of filtration bleb between these two groups (χ(2) = 8.129, P < 0.05). The difference of visual field loss postoperatively between these two groups was not statistically significant. The incidence rate of newly developed cataract after NPTS and TS was 6/31 and 12/32, respectively. The difference of rate of complication between these two groups was statistically non-significant (χ(2) = 3.797, P < 0.05). The successful rate after NPTS and TS was 61.54% (16/26) and 14.29% (4/28), respectively. The difference of successful rate between these two groups was statistically significant (χ(2) = 14.463, P < 0.05). CONCLUSIONS: Both NPTS and TS are effective methods for the treatment of POAG. Postoperative complications after NPTS are less than those of TS, But patients with TS could maintain a lower IOP than those with NPTS. Long-term efficacy of NPTS is uncertain, it's important to choose the suitable surgery to gain a high success rate.


Asunto(s)
Glaucoma de Ángulo Abierto/cirugía , Trabeculectomía/métodos , Adulto , Anciano , Estudios de Casos y Controles , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Resultado del Tratamiento
20.
Nat Commun ; 11(1): 1861, 2020 04 20.
Artículo en Inglés | MEDLINE | ID: mdl-32313096

RESUMEN

Memristive devices are promising candidates to emulate biological computing. However, the typical switching voltages (0.2-2 V) in previously described devices are much higher than the amplitude in biological counterparts. Here we demonstrate a type of diffusive memristor, fabricated from the protein nanowires harvested from the bacterium Geobacter sulfurreducens, that functions at the biological voltages of 40-100 mV. Memristive function at biological voltages is possible because the protein nanowires catalyze metallization. Artificial neurons built from these memristors not only function at biological action potentials (e.g., 100 mV, 1 ms) but also exhibit temporal integration close to that in biological neurons. The potential of using the memristor to directly process biosensing signals is also demonstrated.


Asunto(s)
Potenciales de Acción , Electrónica/instrumentación , Geobacter/metabolismo , Nanocables/química , Neuronas , Técnicas Biosensibles , Electricidad , Diseño de Equipo , Humanos , Simulación de Dinámica Molecular , Nanotecnología/instrumentación , Nanocables/ultraestructura , Redes Neurales de la Computación , Sinapsis/metabolismo , Dispositivos Electrónicos Vestibles
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