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1.
Opt Express ; 32(4): 5760-5769, 2024 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-38439294

RESUMEN

Heme is the prosthetic group for cytochrome that exists in nearly all living organisms and serves as a vital component of human red blood cells (RBCs). Tunable optical nonlinearity in suspensions of RBCs has been demonstrated previously, however, the nonlinear optical response of a pure heme (without membrane structure) solution has not been studied to our knowledge. In this work, we show optical nonlinearity in two common kinds of heme (i.e., hemin and hematin) solutions by a series of experiments and numerical simulations. We find that the mechanism of nonlinearity in heme solutions is distinct from that observed in the RBC suspensions where the nonlinearity can be easily tuned through optical power, concentration, and the solution properties. In particular, we observe an unusual phenomenon wherein the heme solution exhibits negative optical nonlinearity and render self-collimation of a focused beam at specific optical powers, enabling shape-preserving propagation of light to long distances. Our results may have potential applications in optical imaging and medical diagnosis through blood.


Asunto(s)
Eritrocitos , Hemo , Humanos , Imagen Óptica
2.
Environ Sci Technol ; 2024 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-38324705

RESUMEN

A significant amount of organic carbon is transported in dissolved form from soils to coastal oceans via inland water systems, bridging land and ocean carbon reservoirs. However, it has been discovered that the presence of terrigenous dissolved organic carbon (tDOC) in oceans is relatively limited. Therefore, understanding the fates of tDOC in coastal oceans is essential to account for carbon sequestration through land ecosystems and ensure accurate regional carbon budgeting. In this study, we developed a state-of-the-art modeling approach by coupling a land-to-ocean tDOC flux simulation model and a coastal tDOC tracking model to determine the potential fates of tDOC exported from three primary drainage basins in the Gulf of Maine (GoM). According to our findings, over half a year in the GoM, 56.4% of tDOC was mineralized. Biomineralization was responsible for 90% of that amount, with the remainder attributed to photomineralization. Additionally, 37% of the tDOC remained suspended in the GoM, and 6.6% was buried in the marine sediment.

3.
BMC Biol ; 21(1): 51, 2023 03 08.
Artículo en Inglés | MEDLINE | ID: mdl-36882766

RESUMEN

BACKGROUND: Bivalves have independently evolved a variety of symbiotic relationships with chemosynthetic bacteria. These relationships range from endo- to extracellular interactions, making them ideal for studies on symbiosis-related evolution. It is still unclear whether there are universal patterns to symbiosis across bivalves. Here, we investigate the hologenome of an extracellular symbiotic thyasirid clam that represents the early stages of symbiosis evolution. RESULTS: We present a hologenome of Conchocele bisecta (Bivalvia: Thyasiridae) collected from deep-sea hydrothermal vents with extracellular symbionts, along with related ultrastructural evidence and expression data. Based on ultrastructural and sequencing evidence, only one dominant Thioglobaceae bacteria was densely aggregated in the large bacterial chambers of C. bisecta, and the bacterial genome shows nutritional complementarity and immune interactions with the host. Overall, gene family expansions may contribute to the symbiosis-related phenotypic variations in different bivalves. For instance, convergent expansions of gaseous substrate transport families in the endosymbiotic bivalves are absent in C. bisecta. Compared to endosymbiotic relatives, the thyasirid genome exhibits large-scale expansion in phagocytosis, which may facilitate symbiont digestion and account for extracellular symbiotic phenotypes. We also reveal that distinct immune system evolution, including expansion in lipopolysaccharide scavenging and contraction of IAP (inhibitor of apoptosis protein), may contribute to the different manners of bacterial virulence resistance in C. bisecta. CONCLUSIONS: Thus, bivalves employ different pathways to adapt to the long-term co-existence with their bacterial symbionts, further highlighting the contribution of stochastic evolution to the independent gain of a symbiotic lifestyle in the lineage.


Asunto(s)
Bivalvos , Animales , Bivalvos/genética , Transporte Biológico , Genoma Bacteriano , Proteínas Inhibidoras de la Apoptosis , Lipopolisacáridos
4.
Artículo en Inglés | MEDLINE | ID: mdl-37755238

RESUMEN

A novel bacterium, strain QS115T, was isolated from deep-sea sediment collected from the South China Sea at a depth of 1151 m. Phylogenetic analyses based on 16S rRNA gene sequences indicated that QS115T was most closely related to Parasedimentitalea marina W43T, with similarity of 98.21 %. Strain QS115T shared 82.39 % average nucleotide identity, 26.3 % digital DNA-DNA hybridization and 85.32 % average amino acid identity with P. marina W43T. Cells of strain QS115T were Gram-stain-negative, rod-shaped and grew optimally at 10 °C, pH 7.5 and 2 % (w/v) NaCl. The principal fatty acids were summed feature 8 (C18 : 1 ω7c/ω6c), the major respiratory quinone was ubiquinone-10 and predominant polar lipids were diphosphatidylglycerol, phosphatidylethanolamine, glycophospholipid, phosphatidylglycerol and phosphatidylcholine. Polyphasic analyses of physiological and phenotypic characteristics and genomic studies suggested that strain QS115T represents a novel species of the genus Parasedimentitalea, for which the name Parasedimentitalea psychrophila sp. nov. is proposed (type strain QS115T=MCCC 1K04395T=JCM 34219T).


Asunto(s)
Ácidos Grasos , Fosfolípidos , Ácidos Grasos/química , Fosfolípidos/química , Agua de Mar/microbiología , ADN Bacteriano/genética , Filogenia , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Composición de Base , Técnicas de Tipificación Bacteriana , Ubiquinona/química , Bacterias/genética
5.
Neurosurg Rev ; 46(1): 200, 2023 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-37578633

RESUMEN

The application of spinal cord stimulation (SCS) and deep brain stimulation (DBS) for disorders of consciousness (DoC) has been increasingly reported. However, there is no sufficient evidence to determine how effective and safe SCS and DBS are for DoC owing to various methodological limitations. We conducted a systematic review to elucidate the safety and efficacy of SCS and DBS for DoC by systematically reviewing related literature by searching PubMed, EMBASE, Medline, and Cochrane Library. Twenty eligible studies with 608 patients were included in this study. Ten studies with 508 patients reported the efficacy of SCS for DoC, and the estimated overall effectiveness rate was 37%. Five studies with 343 patients reported the efficacy of SCS for VS, and the estimated effectiveness rate was 30%. Three studies with 53 patients reported the efficacy of SCS for MCS, and the estimated effectiveness rate was 63%. Five studies with 92 patients reported the efficacy of DBS for DoC, and the estimated overall effectiveness rate was 40%. Four studies with 63 patients reported the efficacy of DBS for VS, and the estimated effectiveness rate was 26%. Three studies with 19 patients reported the efficacy of DBS for MCS, and the estimated effectiveness rate was 74%. The adverse event rate of DoC was 8.1% and 18.2% after SCS and DBS, respectively. These results suggest that SCS and DBS can be considered reasonable treatments for DoC with considerable efficacy and safety.


Asunto(s)
Estimulación Encefálica Profunda , Estimulación de la Médula Espinal , Humanos , Estimulación de la Médula Espinal/métodos , Estimulación Encefálica Profunda/métodos , Trastornos de la Conciencia/terapia
6.
Chaos ; 33(8)2023 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-37549125

RESUMEN

In this paper, the stability and Bautin bifurcation of a four-wheel-steering (4WS) vehicle system, by considering driver steering control, are investigated. By using the central manifold theory and projection method, the first and second Lyapunov coefficients are calculated to predict the type of Hopf bifurcation of the vehicle system. The topological structure of Bautin bifurcation, a degenerate Hopf bifurcation of the 4WS vehicle system, is presented in parameter space, and it reveals the dynamics of the vehicle system of different choices of control parameters. The influences of system parameters on critical values of the bifurcation parameter are also analyzed. It is shown that with the increase in the frontal visibility distance of the driver control strategy coefficient and the cornering stiffness coefficients of rear wheels, the critical speed increases. Nevertheless, the critical speed decreases with the increase in the distance from the center of gravity of the vehicle to the front axles, Driver's perceptual time delay, and cornering stiffness coefficients of the front wheels.

7.
Neurosurg Rev ; 45(1): 673-682, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34185189

RESUMEN

This study evaluated the long-term efficacy of globus pallidus internus (GPi) deep brain stimulation (DBS) in the treatment of craniofacial dystonia (Meige syndrome) and investigated the correlation between the volume of tissue activated (VTA) in the GPi and each subregion and movement score improvement. We retrospectively analyzed the clinical data of 13 patients with drug-refractory Meige syndrome who were treated with GPi DBS. The pre- and postoperative Burke-Fahn-Marsden Dystonia Rating Scale (BFMDRS) scores were compared. The relationships between the preoperative baseline variables and improvement in the BFMDRS-Movement (BFMDRS-M) score were analyzed. LEAD-DBS software was used for the three-dimensional reconstruction of the GPi and implanted electrodes. The correlations between the GPi-VTA and score improvement were analyzed. The average follow-up period was 36.6 ± 11.0 months (18-55 months). At 3 months after the stimulation and the final follow-up visit, the improvements in the BFMDRS-M score were 58.2 and 54.6%, and the improvements in the BFMDRS-Disability (BFMDRS-D) score were 53.6 and 51.7%, respectively. At the final follow-up visit, the improvements in the BFMDRS-M scores of the eye, mouth, and speech/swallowing were significant (P < 0.001). Age was an independent predictor of improvement in the BFMDRS-M score after DBS (P = 0.005). A decrease in the BFMDRS-M score was significantly positively correlated with the GPi-VTA (r = 0.757, P = 0.003). GPi DBS is an effective method for treating drug-refractory Meige syndrome. LEAD-DBS software can be used as an effective aid for visualization programming after DBS.


Asunto(s)
Estimulación Encefálica Profunda , Distonía , Distonía/terapia , Globo Pálido , Humanos , Estudios Retrospectivos , Resultado del Tratamiento
8.
Chaos ; 32(10): 103106, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36319293

RESUMEN

Nonsmooth systems are widely encountered in engineering fields. They have abundant dynamical phenomena, including some results on the complex dynamics in such systems under quasiperiodically forced excitations. In this work, we consider a quasiperiodically forced piecewise linear oscillator and show that strange nonchaotic attractors (SNAs) do exist in such nonsmooth systems. The generation and evolution mechanisms of SNAs are discussed. The torus-doubling, fractal, bubbling, and intermittency routes to SNAs are identified. The strange properties of SNAs are characterized with the aid of the phase sensitivity function, singular continuous spectrum, rational frequency approximation, and the path of the partial Fourier sum of state variables in a complex plane. The nonchaotic properties of SNAs are verified by the methods of maximum Lyapunov exponent and power spectrum.


Asunto(s)
Fractales , Dinámicas no Lineales , Simulación por Computador
9.
Neurosurg Rev ; 44(1): 115-127, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31814058

RESUMEN

Magnetic resonance imaging-guided focused ultrasound (MRgFUS) neurosurgery is a new option for medication-resistant Parkinson's disease (PD), but its safety and efficacy remain elusive. This study aimed to investigate the safety and efficacy of MRgFUS for PD by systematically reviewing related literature. PubMed and EMBASE were searched to identify related studies. Inclusion criteria were (1) reported the efficacy or safety of MRgFUS for PD and (2) published in English. Exclusion criteria were (1) nonhuman study, (2) review or meta-analysis or other literature types without original data, and (3) conference abstract without full text. Data on study characteristics, treatment parameters, efficacy, and adverse events were collected. Descriptive synthesis of data was performed. Eleven studies containing 80 patients were included. Nine studies were observational studies with no controls. Two studies included a randomized and controlled phase. Most studies included tremor-dominant PD. Ten studies reported decline of UPDRS-III scores after MRgFUS, and five reported a statistically significant decline. Nine studies evaluated the quality of life (QOL). Significant improvement of QOL was reported by four studies using the 39-item Parkinson's disease questionnaire. Four studies investigated the impact of MRgFUS on non-motor symptoms. Most tests indicated that MRgFUS had no significant effect on neuropsychological outcomes. Most adverse events were mild and transient. MRgFUS is a potential treatment for PD with satisfying efficacy and safety. Studies in this field are still limited. More studies with strict design, larger sample size, and longer follow-up are needed to further investigate its efficacy and safety for PD.


Asunto(s)
Imagen por Resonancia Magnética/métodos , Procedimientos Neuroquirúrgicos/métodos , Enfermedad de Parkinson/diagnóstico por imagen , Enfermedad de Parkinson/cirugía , Cirugía Asistida por Computador/métodos , Ultrasonografía/métodos , Humanos , Ensayos Clínicos Controlados Aleatorios como Asunto , Resultado del Tratamiento
10.
Opt Lett ; 45(7): 1830-1833, 2020 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-32236010

RESUMEN

We predict that Bessel-like beams of arbitrary integer order can exhibit a tunable self-similar behavior (that take an invariant form under suitable stretching transformations). Specifically, by engineering the amplitude and the phase on the input plane in real space, we show that it is possible to generate higher-order vortex Bessel-like beams with fully controllable radius of the hollow core and maximum intensity during propagation. In addition, using a similar approach, we show that it is also possible to generate zeroth-order Bessel-like beams with controllable beam width and maximum intensity. Our numerical results are in excellent agreement with our theoretical predictions.

11.
Chaos ; 30(5): 053124, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32491884

RESUMEN

In this paper, the Ricker family (a population model) with quasiperiodic excitation is considered. The existence of strange nonchaotic attractors (SNAs) is analyzed in a co-dimension-2 parameter space by both theoretical and numerical methods. We prove that SNAs exist in a positive measure parameter set. The SNAs are nowhere differentiable (i.e., strange). We use numerical methods to identify the existence of SNAs in a larger parameter set. The nonchaotic property of SNAs is verified by evaluating the Lyapunov exponents, while the strange property is characterized by phase sensitivity and rational approximations. We also find that there is a transition region in a parameter plane in which SNAs alternate with chaotic attractors.

12.
Stereotact Funct Neurosurg ; 97(5-6): 319-336, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31786574

RESUMEN

OBJECTIVE: Anterior capsulotomy (AC) is sometimes used as a life-saving treatment for patients with treatment-refractory obsessive-compulsive disorder (Tr-OCD). Most of the previous studies have assessed only total symptoms and have concluded that AC is a safe and effective procedure. Few of these studies have focused on meticulously investigating the variety of results obtained from patients with different subtypes of OCD. This study reviewed the long-term effects of AC on patients with OCD and analyzed the dissimilarity between particular subtypes of the disease in order to determine which groups are more suited to surgical treatment. METHODS: For this retrospective evaluation, we selected 54 consecutive patients from a total of 63 people with Tr-OCD between 2005 and 2014 who had undergone AC by thermocoagulation at our department. Preoperative and follow-up assessments were conducted at multiple time points (before surgery and 1, 3, 6, 12, and 36 months after surgery). The Yale-Brown Obsessive-Compulsive Scale (Y-BOCS), Hamilton Depression Scale (HAMD), and Hamilton Anxiety Scale (HAMA) were used to quantify the symptoms of OCD. According to different elements (clinical manifestation, comorbidity, and whether a patient was more compulsive or more obsessive), we classified patients into various subtypes and analyzed the variation in symptom improvement and adverse effects. RESULTS: The mean Y-BOCS, HAMD, and HAMA scores were, respectively, 27.03, 23.30, and 21.46 preoperatively and 8.50, 7.07, and 7.42, respectively, at 36 months after surgery. Most patients (n = 43, 79.6%) were shown to have been at least partially responsive to surgical treatment at their long-term follow-up. Six patients demonstrated no obvious improvement (Y-BOCS score decreased by <35%), and 5 patients developed recurrences of their conditions. The following subtypes demonstrated better results: contamination/cleaning; obsessions/checking; compulsive behavior dominant; pure OCD; and OCD with Tourette's -syndrome. The subtypes of aggressive/sexual, obsessive thought dominant, compulsive behavior with obsessive thoughts, OCD comorbidity with bipolar disorder, OCD comorbid with severe depression, and OCD comorbid with psychiatric symptoms showed good outcomes. However, surgery was ineffective for patients with the subtypes of symmetry/ordering, hoarding, pure obsessive thoughts, and OCD with obsessive slowness. CONCLUSIONS: AC is effective in reducing symptoms of OCD. By comparing differently classified follow-up results, we found that patients with most subtypes/dimensions of OCD showed good outcomes. How-ever, patients categorized into the OCD subtypes of pure -obsessive thoughts, symmetry/ordering, hoarding, OCD with obsessive slowness, and OCD comorbid with psychiatric symptoms should take into account these results before undergoing AC.


Asunto(s)
Trastorno Obsesivo Compulsivo/diagnóstico por imagen , Trastorno Obsesivo Compulsivo/cirugía , Psicocirugía/métodos , Adolescente , Adulto , Cognición/fisiología , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Trastorno Obsesivo Compulsivo/psicología , Psicocirugía/tendencias , Estudios Retrospectivos , Factores de Tiempo , Resultado del Tratamiento , Adulto Joven
13.
Phys Rev Lett ; 121(26): 263902, 2018 Dec 28.
Artículo en Inglés | MEDLINE | ID: mdl-30636121

RESUMEN

Flatband systems typically host "compact localized states" (CLS) due to destructive interference and macroscopic degeneracy of Bloch wave functions associated with a dispersionless energy band. Using a photonic Lieb lattice (LL), such conventional localized flatband states are found to be inherently incomplete, with the missing modes manifested as extended line states that form noncontractible loops winding around the entire lattice. Experimentally, we develop a continuous-wave laser writing technique to establish a finite-sized photonic LL with specially tailored boundaries and, thereby, directly observe the unusually extended flatband line states. Such unconventional line states cannot be expressed as a linear combination of the previously observed boundary-independent bulk CLS but rather arise from the nontrivial real-space topology. The robustness of the line states to imperfect excitation conditions is discussed, and their potential applications are illustrated.

14.
Am J Otolaryngol ; 39(6): 676-678, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30032906

RESUMEN

PURPOSE: This study aimed to analyze outcomes of intratympanic injection of dexamethasone after failure of intravenous prednisolone in simultaneous bilateral sudden sensorineural hearing loss (SSNHL). MATERIALS AND METHODS: The cases of simultaneous bilateral SSNHL treated in our hospital from March 2007 to March 2018 were retrospectively analyzed. During the earlier period (March 2007 to February 2012), the cases were treated by intravenous prednisolone only, and classified into group A. During the late period (February 2012 to March 2018), intratympanic injection of dexamethasone after failure of intravenous prednisolone therapy was employed to treat simultaneous bilateral SSNHL, and these patients were enrolled in group B. Effective rates of the two treatment modalities in groups A and B were compared. RESULTS: In group A, 3 of 40 ears obtained complete recovery, and 4 ears achieved partial recovery after intravenous prednisolone treatment, with the effective rate of only 17.5% (7/40 ears). In contrast, 6 of 44 ears in group B achieved complete recovery, and 10 ears got partial recovery, with the effective rate of 36.4% (16/44 ears). There was significant difference in the effective rate between the two groups. CONCLUSION: Intratympanic injection of dexamethasone after failure of intravenous prednisolone therapy was a better choice for simultaneous bilateral SSNHL compared to traditional intravenous prednisolone therapy.


Asunto(s)
Antiinflamatorios/administración & dosificación , Dexametasona/administración & dosificación , Pérdida Auditiva Bilateral/tratamiento farmacológico , Pérdida Auditiva Sensorineural/tratamiento farmacológico , Pérdida Auditiva Súbita/tratamiento farmacológico , Prednisolona/administración & dosificación , Adulto , Anciano , Femenino , Humanos , Inyección Intratimpánica , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Resultado del Tratamiento
15.
J Opt Soc Am A Opt Image Sci Vis ; 34(3): 314-320, 2017 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-28248356

RESUMEN

We present theoretically and experimentally generalized and symmetric Airy beams, where the two sidelobes are not mutually perpendicular, by introducing two rotary angle factors. The symmetric Airy beam is induced by a binary phase pattern. We demonstrate that the intensity distributions of generalized Airy beams are apparently different from those of normal Airy beams. Moreover, they can propagate along arbitrary trajectories. Numerical results show that the generalized and symmetric Airy beams still have the ability of self-healing and nondiffraction. The experimental results are in complete accord with numerical results. Some possible applications are also discussed, and these interesting properties will also likely have potential applications.

16.
J Nanosci Nanotechnol ; 16(1): 648-53, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27398502

RESUMEN

As a newly emerging class of nanomaterials, carbon dots have increasingly attracted researchers' attention. However, their potentially adverse environmental effects are yet largely unknown. In this work, the highly luminescent carbon dots were synthesized by microwave-assisted pyrolysis of tris(hydroxymethyl)aminomethane (Tris) and citric acid. Then acute and chronic toxicities of carbon dots to Physa acuta (P. acuta), as well as their effect on reproduction, were evaluated using the as-synthesized dots as an example. The quantum yield of the as-synthesized carbon dots was up to 53.5% excited at 360 nm with the most fluorescent fraction of 82.6% after simple purification by gel column. The results showed that no acute but chronic toxicities to P. acuta exposed to different treatment concentrations of the as-synthesized carbon dots were observed with dose- dependence. In addition, the fecundity of P. acuta was promoted significantly by the carbon dots at the concentrations of 0.5 and 1.0 mg/mL, yet inhibited at the concentration of 3.0 mg/mL after 12-day exposure. Mainly distributing in the visceral mass might be responsible for the effects of the carbon dots on the survival and fecundity of P. acuta. And there was no further evidence to confirm that the carbon dots can cause malformation in developing embryos.


Asunto(s)
Gastrópodos/metabolismo , Microondas , Puntos Cuánticos , Animales , Relación Dosis-Respuesta a Droga , Puntos Cuánticos/efectos adversos , Puntos Cuánticos/química , Reproducción/efectos de los fármacos
17.
Nanomaterials (Basel) ; 14(5)2024 Feb 24.
Artículo en Inglés | MEDLINE | ID: mdl-38470749

RESUMEN

Among the various reinforcement phases available in Cu-based composites, the unique layered structure and easy diffusion of A-layer atoms make MAX phases more suitable for reinforcing a copper matrix than others. In this study, Cu-coated Ti3AlC2 particles (Cu@Ti3AlC2) were prepared through electroless plating, and Cu@Ti3AlC2/Cu composites were fabricated via vacuum hot-press sintering. The phase composition and microstructure of both Cu@Ti3AlC2 powder and composites were characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The results demonstrate the creation of successful electroless copper plating to obtain a Cu coating on Ti3AlC2 particles. At 850 °C, a small amount of Ti3AlC2 particles decompose to form TiCx, while Al atoms from the A layer of MAX phase diffuse into the Cu matrix to form a solid solution with Cu(Al). The test results reveal that the density of the Cu@Ti3AlC2/Cu composite reaches 98.5%, with a maximum compressive strength of 705 MPa, which is 8.29% higher than that of the Ti3AlC2/Cu composite. Additionally, the compressive strain reaches 37.6%, representing an increase of 12.24% compared to that exhibited by the Ti3AlC2/Cu composite.

18.
Am J Cancer Res ; 14(4): 1446-1465, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38726269

RESUMEN

Liver cancer ranks as the third leading cause of cancer-related mortality worldwide, predominantly in the form of hepatocellular carcinoma (HCC). Conventional detection and treatment approaches have proven inadequate for addressing the elevated incidence and mortality rates associated with HCC. However, a significant body of research suggests that combating HCC through the induction of ferroptosis is possible. Ferroptosis is a regulated cell death process characterized by elevated levels of reactive oxygen species (ROS) and lipid peroxide accumulation, both of which are dependent on iron levels. In recent years, there has been an increasing focus on investigating ferroptosis, revealing its potential as an inhibitory mechanism against various diseases, including tumors. Therefore, ferroptosis induction holds great promise for treating multiple types of cancers, including HCC. This article provides a review of the key mechanisms involved in ferroptosis and explores the potential application of multiple targets and pathways associated with ferroptosis in HCC treatment to improve therapeutic outcomes.

19.
Microbiol Spectr ; 12(3): e0217723, 2024 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-38319114

RESUMEN

Lineage-wise physiological activities of plankton communities in the ocean are important but challenging to characterize. Here, we conducted whole-assemblage metatranscriptomic profiling at continental shelf and slope sites in the South China Sea to investigate carbon fixation potential in different lineages. RuBisCO expression, the proxy of Calvin carbon fixation (CCF) potential, was mainly contributed by Bacillariophyta, Chlorophyta, Cyanobacteria, and Haptophyta, which was differentially affected by environmental factors among lineages. CCF potential exhibited positive or negative correlations with phagotrophy gene expression, suggesting phagotrophy possibly enhances or complements CCF. Our data also reveal significant non-Calvin carbon fixation (NCF) potential, as indicated by the active expression of genes in all five currently recognized NCF pathways, mainly contributed by Flavobacteriales, Alteromonadales, and Oceanospirillales. Furthermore, in Flavobacteriales, Alteromonadales, Pelagibacterales, and Rhodobacterales, NCF potential was positively correlated with proton-pump rhodopsin (PPR) expression, suggesting that NCF might be energetically supported by PPR. The novel insights into the lineage-differential potential of carbon fixation, widespread mixotrophy, and PPR as an energy source for NCF lay a methodological and informational foundation for further research to understand carbon fixation and the trophic landscape in the ocean.IMPORTANCEMarine plankton plays an important role in global carbon cycling and climate regulation. Phytoplankton and cyanobacteria fix CO2 to produce organic compounds using solar energy and mainly by the Calvin cycle, whereas autotrophic bacteria and archaea may fix CO2 by non-Calvin cycle carbon fixation pathways. How active individual lineages are in carbon fixation and mixotrophy, and what energy source bacteria may employ in non-Calvin carbon fixation, in a natural plankton assemblage are poorly understood and underexplored. Using metatranscriptomics, we studied carbon fixation in marine plankton with lineage resolution in tropical marginal shelf and slope areas. Based on the sequencing results, we characterized the carbon fixation potential of different lineages and assessed Calvin- and non-Calvin- carbon fixation activities and energy sources. Data revealed a high number of unigenes (4.4 million), lineage-dependent differential potentials of Calvin carbon fixation and responses to environmental conditions, major contributors of non-Calvin carbon fixation, and their potential energy source.


Asunto(s)
Cianobacterias , Flavobacteriaceae , Gammaproteobacteria , Plancton/genética , Dióxido de Carbono/metabolismo , Archaea/metabolismo , Flavobacteriaceae/metabolismo , Gammaproteobacteria/metabolismo , Perfilación de la Expresión Génica , Carbono/metabolismo
20.
Front Pediatr ; 12: 1308931, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38720947

RESUMEN

Background: Idiopathic scoliosis significantly affects the physical and mental health of children and adolescents, with varying prevalence rates in different regions. The occurrence of idiopathic scoliosis is associated with genetic regulation and biochemical factors, but the changes in exosome-derived miRNA profiles among idiopathic scoliosis patients remain unclear. This study aimed to determine the prevalence of idiopathic scoliosis in Yunnan Province, China, and identify key exosome-derived miRNAs in idiopathic scoliosis through a cohort study. Methods: From January 2018 to December 2020, a cross-sectional study on idiopathic scoliosis in children and adolescents was conducted in Yunnan Province. A total of 84,460 students from 13 cities and counties in Yunnan Province participated in a scoliosis screening program, with ages ranging from 7 to 19 years. After confirmation through screening and imaging results, patients with severe idiopathic scoliosis and normal control individuals were selected using propensity matching. Subsequently, plasma exosome-derived miRNA sequencing and RT-qPCR validation were performed separately. Based on the validation results, diagnostic performance analysis and target gene prediction were conducted for differential plasma exosome-derived miRNAs. Results: The overall prevalence of idiopathic scoliosis in children and adolescents in Yunnan Province was 1.10%, with a prevalence of 0.87% in males and 1.32% in females. The peak prevalence was observed at age 13. Among patients diagnosed with idiopathic scoliosis, approximately 12.8% had severe cases, and there were more cases of double curvature than of single curvature, with thoracolumbar curvature being the most common in the single-curvature group. Sequencing of plasma exosome-derived miRNAs associated with idiopathic scoliosis revealed 56 upregulated and 153 downregulated miRNAs. Further validation analysis confirmed that hsa-miR-27a-5p, hsa-miR-539-5p, and hsa-miR-1246 have potential diagnostic value. Conclusions: We gained insights into the epidemiological characteristics of idiopathic scoliosis in Yunnan Province and conducted further analysis of plasma exosome-derived miRNA changes in patients with severe idiopathic scoliosis. This study has provided new insights for the prevention and diagnosis of idiopathic scoliosis, paving the way for exploring clinical biomarkers and molecular regulatory mechanisms. However, further validation and elucidation of the detailed biological mechanisms underlying these findings will be required in the future.

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