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1.
Nature ; 610(7933): 791-795, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-36108674

RESUMEN

Parkinson's disease (PD) is the most common movement disorder, with resting tremor, rigidity, bradykinesia and postural instability being major symptoms1. Neuropathologically, it is characterized by the presence of abundant filamentous inclusions of α-synuclein in the form of Lewy bodies and Lewy neurites in some brain cells, including dopaminergic nerve cells of the substantia nigra2. PD is increasingly recognised as a multisystem disorder, with cognitive decline being one of its most common non-motor symptoms. Many patients with PD develop dementia more than 10 years after diagnosis3. PD dementia (PDD) is clinically and neuropathologically similar to dementia with Lewy bodies (DLB), which is diagnosed when cognitive impairment precedes parkinsonian motor signs or begins within one year from their onset4. In PDD, cognitive impairment develops in the setting of well-established PD. Besides PD and DLB, multiple system atrophy (MSA) is the third major synucleinopathy5. It is characterized by the presence of abundant filamentous α-synuclein inclusions in brain cells, especially oligodendrocytes (Papp-Lantos bodies). We previously reported the electron cryo-microscopy structures of two types of α-synuclein filament extracted from the brains of individuals with MSA6. Each filament type is made of two different protofilaments. Here we report that the cryo-electron microscopy structures of α-synuclein filaments from the brains of individuals with PD, PDD and DLB are made of a single protofilament (Lewy fold) that is markedly different from the protofilaments of MSA. These findings establish the existence of distinct molecular conformers of assembled α-synuclein in neurodegenerative disease.


Asunto(s)
Química Encefálica , Encéfalo , Microscopía por Crioelectrón , Enfermedad por Cuerpos de Lewy , alfa-Sinucleína , Humanos , alfa-Sinucleína/química , alfa-Sinucleína/metabolismo , alfa-Sinucleína/ultraestructura , Encéfalo/metabolismo , Encéfalo/patología , Encéfalo/ultraestructura , Enfermedad por Cuerpos de Lewy/patología , Enfermedad de Parkinson/complicaciones , Enfermedad de Parkinson/patología , Demencia/complicaciones , Demencia/patología
2.
Proc Natl Acad Sci U S A ; 119(37): e2122032119, 2022 09 13.
Artículo en Inglés | MEDLINE | ID: mdl-36067315

RESUMEN

Photosynthetic organisms have developed a regulation mechanism called state transition (ST) to rapidly adjust the excitation balance between the two photosystems by light-harvesting complex II (LHCII) movement. Though many researchers have assumed coupling of the dynamic transformations of the thylakoid membrane with ST, evidence of that remains elusive. To clarify the above-mentioned coupling in a model organism Chlamydomonas, here we used two advanced microscope techniques, the excitation-spectral microscope (ESM) developed recently by us and the superresolution imaging based on structured-illumination microscopy (SIM). The ESM observation revealed ST-dependent spectral changes upon repeated ST inductions. Surprisingly, it clarified a less significant ST occurrence in the region surrounding the pyrenoid, which is a subcellular compartment specialized for the carbon-fixation reaction, than that in the other domains. Further, we found a species dependence of this phenomenon: 137c strain showed the significant intracellular inhomogeneity of ST occurrence, whereas 4A+ strain hardly did. On the other hand, the SIM observation resolved partially irreversible fine thylakoid transformations caused by the ST-inducing illumination. This fine, irreversible thylakoid transformation was also observed in the STT7 kinase-lacking mutant. This result revealed that the fine thylakoid transformation is not induced solely by the LHCII phosphorylation, suggesting the highly susceptible nature of the thylakoid ultrastructure to the photosynthetic light reactions.


Asunto(s)
Chlamydomonas , Complejos de Proteína Captadores de Luz , Complejo de Proteína del Fotosistema II , Tilacoides , Chlamydomonas/enzimología , Chlamydomonas/efectos de la radiación , Luz , Complejos de Proteína Captadores de Luz/química , Fosforilación , Fotosíntesis/fisiología , Complejo de Proteína del Fotosistema II/química , Tilacoides/enzimología , Tilacoides/efectos de la radiación
3.
Int Wound J ; 21(1): e14582, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38272818

RESUMEN

This meta-analysis assesses the impact of Enhanced Recovery After Surgery (ERAS) protocols on surgical site wound infections (SSWIs) in urological procedures. Analysing data from 10 studies, our focus was on SSWI rates on the third and seventh postoperative days. The results reveal a significant reduction in SSWI rates for patients managed under ERAS protocols compared with traditional care. Notably, Figure 4 demonstrates a substantial decrease in SSWI on the third day (I2 = 93%; random: standardized mean difference [SMD]: -6.25, 95% confidence interval [CI]: -7.42 to -5.05, p < 0.01), and Figure 5 mirrors this trend on the seventh day (I2 = 95%; random: SMD: -4.72, 95% CI: -6.28 to -3.16, p < 0.01). These findings underscore the effectiveness of ERAS protocols in minimizing early postoperative wound infections, emphasizing their importance for broader implementation in urological surgeries.


Asunto(s)
Recuperación Mejorada Después de la Cirugía , Infección de la Herida Quirúrgica , Humanos , Tiempo de Internación , Complicaciones Posoperatorias , Periodo Posoperatorio , Infección de la Herida Quirúrgica/prevención & control
4.
Acta Neuropathol ; 145(5): 561-572, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36847833

RESUMEN

A 21-nucleotide duplication in one allele of SNCA was identified in a previously described disease with abundant α-synuclein inclusions that we now call juvenile-onset synucleinopathy (JOS). This mutation translates into the insertion of MAAAEKT after residue 22 of α-synuclein, resulting in a protein of 147 amino acids. Both wild-type and mutant proteins were present in sarkosyl-insoluble material that was extracted from frontal cortex of the individual with JOS and examined by electron cryo-microscopy. The structures of JOS filaments, comprising either a single protofilament, or a pair of protofilaments, revealed a new α-synuclein fold that differs from the folds of Lewy body diseases and multiple system atrophy (MSA). The JOS fold consists of a compact core, the sequence of which (residues 36-100 of wild-type α-synuclein) is unaffected by the mutation, and two disconnected density islands (A and B) of mixed sequences. There is a non-proteinaceous cofactor bound between the core and island A. The JOS fold resembles the common substructure of MSA Type I and Type II dimeric filaments, with its core segment approximating the C-terminal body of MSA protofilaments B and its islands mimicking the N-terminal arm of MSA protofilaments A. The partial similarity of JOS and MSA folds extends to the locations of their cofactor-binding sites. In vitro assembly of recombinant wild-type α-synuclein, its insertion mutant and their mixture yielded structures that were distinct from those of JOS filaments. Our findings provide insight into a possible mechanism of JOS fibrillation in which mutant α-synuclein of 147 amino acids forms a nucleus with the JOS fold, around which wild-type and mutant proteins assemble during elongation.


Asunto(s)
Atrofia de Múltiples Sistemas , Sinucleinopatías , Humanos , alfa-Sinucleína/genética , alfa-Sinucleína/metabolismo , Sinucleinopatías/genética , Nigeria , Atrofia de Múltiples Sistemas/genética , Atrofia de Múltiples Sistemas/metabolismo , Mutación/genética
5.
Yi Chuan ; 45(1): 67-77, 2023 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-36927639

RESUMEN

The abnormal modification of histone is an important factor restricting development of porcine cloned embryos. Overexpression of histone H3K9me3 demethylase KDM4 family can effectively improve the developmental efficiency of cloned embryos. In order to explore the effects of overexpression of H3K9me3 demethylase on the development of porcine cloned embryos, KDM4A mRNA and KDM4D mRNA were injected respectively into porcine cloned embryos at the 1-cell stage and 2-cell stage to detect the blastocyst rate; 2-cell stage cloned embryos injected with KDM4A mRNA and embryo injection water (the control group) at the 1-cell stage were collected to detect the expression level of H3K9me3, and 4-cell stage cloned embryos were collected for single cell transcriptome sequencing, then the sequencing data was analyzed with KEGG and GO. The results showed that the blastocyst rate of porcine cloned embryos injected with KDM4A mRNA at 1-cell stage was significantly higher than that of the control group (25.32 ± 0.74% vs 14.78 ± 0.87%), while cloned embryos injected with KDM4D mRNA had a similar blastocyst rate with cloned embryos in control group (16.27 ± 0.77% vs 14.78 ± 0.87%). Porcine cloned embryos injected with KDM4A mRNA and KDM4D mRNA at 2-cell stage had a similar blastocyst rate with cloned embryos in control group (32.18 ± 1.67%, 30.04 ± 0.91% vs 31.22 ± 1.40%). The expression level of H3K9me3 in cloned embryos injected with KDM4A mRNA at 1-cell stage was lower than that in control group. There were 133 differentially expressed genes detected by transcriptome sequencing, including 52 up-regulated genes and 81 down-regulated genes. Pathways enriched by GO analyses were mainly related to protein localization. Pathways enriched by KEGG analyses were related to cellular senescence and acute myeloid leukemia. These results suggest that overexpression of histone H3K9me3 demethylase KDM4A can significantly improve the developmental efficiency of porcine cloned embryos.


Asunto(s)
Histona Demetilasas , Histonas , Porcinos/genética , Animales , Histona Demetilasas/metabolismo , Histona Demetilasas/farmacología , Histonas/genética , Histonas/metabolismo , Técnicas de Transferencia Nuclear , Desarrollo Embrionario/genética , Blastocisto/metabolismo , ARN Mensajero/metabolismo , Clonación de Organismos
6.
Trends Biochem Sci ; 43(12): 1033-1046, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30309741

RESUMEN

Class Frizzled G protein-coupled receptors (GPCRs), which includes the Smoothened receptor (SMO) and 10 Frizzled receptors (FZDs), are responsible for mediating fundamental signaling in embryonic development and tissue homeostasis. Dysregulation of these receptors can lead to cancer. Structural understanding of these molecules has provided insight to their function and signaling, and guided drug discovery. To date, the structures of the multi- and individual domains of SMO, 14 FZD extracellular domains, and the transmembrane domain (TMD) of FZD4, have been reported. Here, we review all reported frizzled family structures and diverse signalosome models, with an emphasis on the different ligand binding sites and lipid binding grooves, aiming to uncover the druggability landscape of the frizzled GPCR family.


Asunto(s)
Receptores Frizzled/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Animales , Receptores Frizzled/química , Humanos , Receptores Acoplados a Proteínas G/química , Receptor Smoothened/química , Receptor Smoothened/metabolismo
7.
Molecules ; 27(20)2022 Oct 12.
Artículo en Inglés | MEDLINE | ID: mdl-36296422

RESUMEN

The quality of in vitro matured oocytes is inferior to that of in vivo matured oocytes, which translates to low developmental capacity of embryos derived from in vitro matured oocytes. The developmental potential of in vitro matured oocytes is usually impaired due to oxidative stress. Stromal cell-derived factor-l (SDF1) can reduce oxidative stress and inhibit apoptosis. The aim of this study was to investigate the effects of SDF1 supplementation during pig oocyte in vitro maturation (IVM) on subsequent embryo development, and to explore the acting mechanisms of SDF1 in pig oocytes. We found that the IVM medium containing 20 ng/mL SDF1 improved the maturation rate of pig oocytes, as well as the cleavage rate and blastocyst rate of embryos generated by somatic cell nuclear transfer, in vitro fertilization, and parthenogenesis. Supplementation of 20 ng/mL SDF1 during IVM decreased the ROS level, increased the mitochondrial membrane potential, and altered the expression of apoptosis-related genes in the pig oocytes. The porcine oocyte transcriptomic data showed that SDF1 addition during IVM altered the expression of genes enriched in the purine metabolism and TNF signaling pathways. SDF1 supplementation during pig oocyte IVM also upregulated the mRNA and protein levels of YY1 and TET1, two critical factors for oocyte development. In conclusion, supplementation of SDF1 during pig oocyte IVM reduces oxidative stress, changes expression of genes involved in regulating apoptosis and oocyte growth, and enhances the ability of in vitro matured pig oocytes to support subsequent embryo development. Our findings provide a theoretical basis and a new method for improving the developmental potential of pig in vitro matured oocytes.


Asunto(s)
Desarrollo Embrionario , Técnicas de Maduración In Vitro de los Oocitos , Porcinos , Animales , Técnicas de Maduración In Vitro de los Oocitos/métodos , Especies Reactivas de Oxígeno/farmacología , Suplementos Dietéticos , ARN Mensajero , Purinas/farmacología
8.
Med Sci Monit ; 27: e926760, 2021 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-33788826

RESUMEN

BACKGROUND Hepatocellular carcinoma (HCC) occurs frequently in China, with high morbidity and mortality. Cell division cycle 20 homolog (CDC20) is reportedly related to many cancers. In this study, we discuss a potential link of CDC20 expression to HCC patients' prognoses. MATERIAL AND METHODS Quantitative real-time polymerase chain reaction (qRT-PCR) was performed to assess CDC20 expression in HCC and the paired noncancerous tissues. Chi-square analysis was used to assess potential association of CDC20 expression with clinicopathologic profiles among HCC patients. The overall survival for HCC patients with different CDC20 expressions was assessed using the Kaplan-Meier method. To evaluate the prognostic value for HCC patients, Cox regression analyses were performed. RESULTS The expression of CDC20 was elevated among HCC specimens compared with adjacent noncancerous ones (P<0.05). The expression of CDC20 was significantly related to differentiation (P<0.001), tumor node metastasis stage (P<0.001), and lymphatic metastasis (P<0.001). Moreover, HCC patients with high CDC20 expression had dismal overall survival rates compared with low CDC20 expression (P<0.05). CDC20 alone could forecast HCC prognoses according to multivariable Cox regression analysis (hazard ratio=2.354, 95% confidence interval=1.177-4.709, P=0.016). CONCLUSIONS Overexpressed CDC20 may act as a reliable biomarker for dismal prognoses among HCC patients.


Asunto(s)
Biomarcadores de Tumor/metabolismo , Carcinoma Hepatocelular/diagnóstico , Proteínas Cdc20/metabolismo , Neoplasias Hepáticas/diagnóstico , Biomarcadores de Tumor/genética , Carcinoma Hepatocelular/mortalidad , Proteínas Cdc20/genética , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Neoplasias Hepáticas/mortalidad , Masculino , Persona de Mediana Edad , Metástasis de la Neoplasia , Estadificación de Neoplasias , Pronóstico , Modelos de Riesgos Proporcionales , Análisis de Supervivencia , Regulación hacia Arriba
9.
Epilepsy Behav ; 110: 107156, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32502930

RESUMEN

Many seizure-free patients who consider withdrawing from antiepileptic drugs (AEDs) hope to discontinue treatment to avoid adverse effects. However, withdrawal has certain risks that are difficult to predict. In this study, we performed a literature review, summarized the causes of significant variability in the risk of postwithdrawal recurrent seizures, and reviewed study data on the age at onset, cause, types of seizures, epilepsy syndrome, magnetic resonance imaging (MRI) abnormalities, epilepsy surgery, and withdrawal outcomes of patients with epilepsy. Many factors are associated with recurrent seizures after AED withdrawal. For patients who are seizure-free after treatment, the role of an electroencephalogram (EEG) alone in ensuring safe withdrawal is limited. A series of prediction models for the postwithdrawal recurrence risk have incorporated various potentially important factors in a comprehensive analysis. We focused on the populations of studies investigating five risk prediction models and analyzed the predictive variables and recommended applications of each model, aiming to provide a reference for personalized withdrawal for patients with epilepsy in clinical practice.


Asunto(s)
Anticonvulsivantes/uso terapéutico , Epilepsia/diagnóstico por imagen , Epilepsia/tratamiento farmacológico , Síndrome de Abstinencia a Sustancias/diagnóstico por imagen , Electroencefalografía/tendencias , Epilepsia/fisiopatología , Humanos , Imagen por Resonancia Magnética/tendencias , Valor Predictivo de las Pruebas , Estudios Prospectivos , Recurrencia , Estudios Retrospectivos , Factores de Riesgo , Convulsiones/diagnóstico por imagen , Convulsiones/tratamiento farmacológico , Convulsiones/fisiopatología , Síndrome de Abstinencia a Sustancias/fisiopatología
10.
Trends Biochem Sci ; 40(2): 79-87, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25601764

RESUMEN

Traditionally, G protein-coupled receptor (GPCR) activity has been characterized by ligand properties including affinity (Ki), potency (IC50/EC50), efficacy (Emax), and kinetics (Kon/Koff). These properties are related to ligand residence time, a general index of drug-target interaction in vivo. Recent GPCR structure-function breakthroughs have all required ligand stabilization of the receptor in some manner, highlighting the natural instability of these important cell surface receptors. This research has initiated a new era of discovery that highlights the importance of ligand-receptor interactions beyond the traditional mindset. We propose that receptor stability is related to receptor folding and residence in the cell membrane, affording a new dimension that should be considered when studying receptor function.


Asunto(s)
Ligandos , Receptores Acoplados a Proteínas G/metabolismo , Relación Estructura-Actividad , Membrana Celular/química , Membrana Celular/metabolismo , Cinética , Unión Proteica , Receptores Acoplados a Proteínas G/química
11.
Org Biomol Chem ; 17(25): 6136-6142, 2019 06 26.
Artículo en Inglés | MEDLINE | ID: mdl-31180094

RESUMEN

The smoothened receptor (SMO) mediates the hedgehog (Hh) signaling pathway and plays a vital role in embryonic development and tumorigenesis. The visualization of SMO has the potential to provide new insights into its enigmatic mechanisms and associated disease pathogenesis. Based on recent progress in structural studies of SMO, we have designed and characterized a group of affinity probes to facilitate the turn-on fluorescence labeling of SMO at the ε-amine of K395. These chemical probes were derived from a potent SMO antagonist skeleton by the conjugation of a small non-fluorescent unit, O-nitrobenzoxadiazole (O-NBD). In this context, optimal probes were developed to be capable of efficiently and selectively lighting up SMO regardless of whether it is in micelles or in native membranes. More importantly, the resulting labeled SMO only bears a very small fluorophore and allows for the recovery of the unoccupied pocket by dissociation of the residual ligand module. These advantages should allow the probe to serve as a potential tool for monitoring SMO trafficking, understanding Hh activation mechanisms, and even the diagnosis of tumorigenesis in the future.

15.
Neurol Sci ; 37(1): 123-130, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26337284

RESUMEN

Alleles of IL-17A and IL-17F genes were reported to be associated with many inflammatory and autoimmune disorders in Asian patients. Serum level and mRNA of IL-17A in peripheral blood mononuclear cells were reported to be significantly higher in MG patients than in healthy controls. In experimental autoimmune myasthenia gravis (EAMG) animals, IL-17 may have effects on the severity of MG. This study investigated the association between four SNPs of IL-17A and IL-17F gene (rs8193036, rs2275913 and rs3748067 in IL-17A; rs763780 in IL-17F) and MG in Chinese patients. The allele frequencies were compared between 480 MG patients and 487 healthy controls, between each MG subgroup and the control group, and between each pairs of MG subgroups. Subgroups were specified by clinical features (onset age, gender, thymoma, AChRAb and muscle involvement at onset) and maximal severity during the follow-up. No associations were found between the four SNPs of IL-17A and IL-17F gene and MG in Chinese patients.


Asunto(s)
Interleucina-17/genética , Miastenia Gravis/genética , Polimorfismo de Nucleótido Simple , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Pueblo Asiatico/genética , Niño , Preescolar , China , Femenino , Estudios de Seguimiento , Frecuencia de los Genes , Estudios de Asociación Genética , Humanos , Lactante , Masculino , Persona de Mediana Edad , Índice de Severidad de la Enfermedad , Adulto Joven
16.
J Cell Mol Med ; 19(4): 836-49, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25661015

RESUMEN

Macrophage migration inhibitory factor (MIF) involves the pathogenesis of atherosclerosis (AS) and increased plasma MIF levels in diabetes mellitus (DM) patients are associated with AS. Here, we have been suggested that MIF could be a critical contributor for the pathological process of diabetes-associated AS by using adenovirus-mediated RNA interference. First, streptozotocin (STZ)-induced diabetic animal model was constructed in 114 apolipoprotein E-deficient mice (apoE-/- mice) fed on a regular chow diet. Then, the animals were randomly divided into three groups: Adenovirus-mediated MIF interference (Ad-MIFi), Ad-enhanced green fluorescent protein (EGFP) and normal saline (NS) group (n ≈ 33/group). Non-diabetic apoE-/- mice (n = 35) were served as controls. Ad-MIFi, Ad-EGFP and NS were, respectively, injected into the tail vein of mice from Ad-MIFi, Ad-EGFP and NS group, which were injected repeatedly 4 weeks later. Physical, biochemical, morphological and molecular parameters were measured. The results showed that diabetic apoE-/- mice had significantly aggravated atherosclerotic lesions. MIF gene interference attenuated atherosclerotic lesions and stabilized atheromatous plaque, accompanied by the decreased macrophages and lipids deposition and inflammatory cytokines production, improved glucose intolerance and plasma cholesterol level, the decreased ratio of matrix matalloproteinase-2/tissue inhibitor of metalloproteinase-1 and plaque instability index. An increased expression of MIF and its ligand CD74 was also detected in the diabetic patients with coronary artery disease. The results suggest that MIF gene interference is able to inhibit atherosclerotic lesions and increase plaque stability in diabetic apoE-/-mice. MIF inhibition could be a novel and promising approach to the treatment of DM-associated AS.


Asunto(s)
Apolipoproteínas E/metabolismo , Aterosclerosis/metabolismo , Diabetes Mellitus Experimental/metabolismo , Oxidorreductasas Intramoleculares/metabolismo , Factores Inhibidores de la Migración de Macrófagos/metabolismo , Animales , Antígenos de Diferenciación de Linfocitos B/genética , Antígenos de Diferenciación de Linfocitos B/metabolismo , Apolipoproteínas E/genética , Apoptosis/genética , Aterosclerosis/complicaciones , Aterosclerosis/genética , Western Blotting , Colesterol/sangre , Citocinas/genética , Citocinas/metabolismo , Diabetes Mellitus Experimental/complicaciones , Diabetes Mellitus Experimental/genética , Expresión Génica , Antígenos de Histocompatibilidad Clase II/genética , Antígenos de Histocompatibilidad Clase II/metabolismo , Inmunohistoquímica , Mediadores de Inflamación/metabolismo , Oxidorreductasas Intramoleculares/genética , Receptores X del Hígado , Factores Inhibidores de la Migración de Macrófagos/genética , Ratones Noqueados , Receptores Nucleares Huérfanos/genética , Receptores Nucleares Huérfanos/metabolismo , PPAR alfa/genética , PPAR alfa/metabolismo , Interferencia de ARN , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
17.
J Stomatol Oral Maxillofac Surg ; : 101904, 2024 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-38705514

RESUMEN

The objective of this study is to verify the role of digital modified parotid tumor zoning method in modified parotid incision. The data of patients with parotid benign tumors from November 2021 to December 2023 were collected. Through the use of digital technology for soft tissue reconstruction, the parotid tumor was divided into four areas according to the digital image marker points. We designed the surgical incision according to the parotid gland division, found that it was feasible to guide the incision selection by division, and summarized the common incision and division corresponding, zone I was I and V-shaped incision, zone II was V incision, zone III was V and C- shaped incision, and zone IV was C- shaped incision. We conclude that the digital modified parotid gland zoning method can provide a better distinction in the surgical incision, and provide a better cosmetic incision and prognosis.

18.
J Phys Chem B ; 128(11): 2664-2674, 2024 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-38456814

RESUMEN

In the development of single-molecule spectroscopy, the simultaneous detection of the excitation and emission spectra has been limited. The fluorescence excitation spectrum based on background-free signals is compatible with the fluorescence-emission-based detection of single molecules and can provide insight into the variations in the input energy of the different terminal emitters. Here, we implement single-molecule excitation-emission spectroscopy (SMEES) for photosystem I (PSI) via a cryogenic optical microscope. To this end, we extended our line-focus-based excitation-spectral microscope system to the cryogenic temperature-compatible version. PSI is one of the two photosystems embedded in the thylakoid membrane in oxygen-free photosynthetic organisms. PSI plays an essential role in electron transfer in the photosynthesis reaction. PSIs of many organisms contain a few red-shifted chlorophylls (Chls) with much lower excitation energies than ordinary antenna Chls. The fluorescence emission spectrum originates primarily from the red-shifted Chls, whereas the excitation spectrum is sensitive to the antenna Chls that are upstream of red-shifted Chls. Using SMEES, we obtained the inclining two-dimensional excitation-emission matrix (2D-EEM) of PSI particles isolated from a cyanobacterium, Thermosynechococcus vestitus (equivalent to elongatus), at about 80 K. Interestingly, by decomposing the inclining 2D-EEMs within time course observation, we found prominent variations in the excitation spectra of the red-shifted Chl pools with different emission wavelengths, strongly indicating the variable excitation energy transfer (EET) pathway from the antenna to the terminal emitting pools. SMEES helps us to directly gain information about the antenna system, which is fundamental to depicting the EET within pigment-protein complexes.


Asunto(s)
Cianobacterias , Complejo de Proteína del Fotosistema I , Complejo de Proteína del Fotosistema I/química , Imagen Individual de Molécula , Espectrometría de Fluorescencia , Cianobacterias/química , Temperatura , Clorofila/química
19.
Orthop Surg ; 16(6): 1336-1343, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38654387

RESUMEN

OBJECTIVE: The reported date in the repeat surgical intervention for adolescent lumbar disc herniation (ALDH) after percutaneous endoscopic lumbar discectomy (PELD) was quite scarce. This study aims to introduce cases of repeat surgeries after PELD for ALDH and assess the incidence, chief causes, repeat surgery methods, and surgical outcomes of repeat surgeries after PELD for ALDH. METHODS: A retrospective multicenter observational study was conducted on patients undergoing repeat surgeries after PELD for ALDH at four tertiary referral hospitals from January 2014 through August 2022. The incidence of repeat surgeries, chief causes, strategies for repeat surgeries, and timing of repeat surgeries were recorded and analyzed. The clinical outcomes were evaluated by the Numeric Rating Scales (NRS) scores and the modified MacNab criteria. Statistical analyses were performed with the Wilcoxon signed-rank test. RESULTS: A total of 23 patients who underwent repeat surgeries after PELD for ALDH were included. The chief causes were re-herniation (homo-lateral re-herniation at the same level, new disc herniation of adjacent level). The repeat surgery methods were revision PELD, micro-endoscopic discectomy (MED), open discectomy and instrumented lumbar inter-body fusion. The NRS scores decreased significantly in follow-up evaluations and these scores demonstrated significant improvement at the last follow-up (p < 0.002). For the modified MacNab criteria, at the last follow-up, 18 patients (78.26%) had an excellent outcome, and the overall success rate was 86.95%. CONCLUSION: This study's data suggest that young patients who underwent repeat surgery improved significantly compared to baseline. The chief cause was re-herniation. Revision PELD was the main surgical procedure, which provides satisfactory clinical results in young patients who underwent repeat surgeries.


Asunto(s)
Discectomía Percutánea , Endoscopía , Desplazamiento del Disco Intervertebral , Vértebras Lumbares , Reoperación , Humanos , Desplazamiento del Disco Intervertebral/cirugía , Adolescente , Estudios Retrospectivos , Masculino , Femenino , Vértebras Lumbares/cirugía , Discectomía Percutánea/métodos , Endoscopía/métodos , Adulto Joven
20.
Zhonghua Yi Xue Za Zhi ; 93(20): 1583-4, 2013 May 28.
Artículo en Zh | MEDLINE | ID: mdl-24028730

RESUMEN

OBJECTIVE: To evaluate the feasibility and clinical results of subsequent retroperitoneoscopic surgery for patients with previous ipsilateral retroperitoneal surgery through frank incision. METHODS: A total of 10 patents were selected for subsequent laparoscopic surgery through retroperitoneal approach. Among them, there were recurrent renal cysts (n = 4) including a history of open surgery (n = 1) and retroperitoneal surgery (n = 3) and nonfunctional kidneys (n = 6) including open nephropyelopolasty (n = 3), retroperitoneoscopic nephropyelopolasty (n = 1) and retroperitoneoscopic ureterolithotomy (n = 2). The mean surgical duration was (12-85) 38.6 months. All patients underwent retroperitoneoscopy. Decortication was performed for renal cysts and nephrectomy for nonfunctional kidneys. RESULTS: All operations were successfully performed with a mean surgical duration of 97 (40-185) minutes and a mean volume of blood loss 125 (20-460) ml. Among 4 cases with intraoperative peritoneal rupture, one case had renal cyst on ventral side. After enlargement, the procedure was performed through peritoneal cavity. The mean postoperative hospital stay was 5.6 (3-9) days. Nine patients received a mean follow-up period of 21.5 (3-47) months. All symptoms were relieved without any occurrence of postoperative complications. CONCLUSION: For patients with previous ipsilateral retroperitoneal surgery, retroperitoneoscopy may be feasible for properly selected cases.


Asunto(s)
Laparoscopía/métodos , Procedimientos Quirúrgicos Urológicos/métodos , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Nefrectomía/métodos , Reoperación , Resultado del Tratamiento
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