Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 1.787
Filtrar
Más filtros

Intervalo de año de publicación
1.
Proc Natl Acad Sci U S A ; 121(9): e2319286121, 2024 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-38394244

RESUMEN

Hydrogen (H2) and hydrogen peroxide (H2O2) play crucial roles as energy carriers and raw materials for industrial production. However, the current techniques for H2 and H2O2 production rely on complex catalysts and involve multiple intermediate steps. In this study, we present a straightforward, environmentally friendly, and highly efficient laser-induced conversion method for overall water splitting to simultaneously generate H2 and H2O2 at ambient conditions without any catalysts. The laser direct overall water splitting approach achieves an impressive light-to-hydrogen energy conversion efficiency of 2.1%, with H2 production rates of 2.2 mmol/h and H2O2 production rates of 65 µM/h in a limited reaction area (1 mm2) within a short real reaction time (0.36 ms/h). Furthermore, we elucidate the underlying physics and chemistry behind the laser-induced water splitting to produce H2 and H2O2. The laser-induced cavitation bubbles create an optimal microenvironment for water-splitting reactions because of the transient high temperatures (104 K) surpassing the chemical barrier required. Additionally, their rapid cooling rate (1010 K/s) hinders reverse reactions and facilitates H2O2 retention. Finally, upon bubble collapse, H2 is released while H2O2 remains dissolved in the water. Moreover, a preliminary amplification experiment demonstrates the potential industrial applications of this laser chemistry. These findings highlight that laser-based production of H2 and H2O2 from water holds promise as a straightforward, environmentally friendly, and efficient approach on an industrial scale beyond conventional chemical catalysis.

2.
Development ; 150(13)2023 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-37272421

RESUMEN

Oocytes develop in the germline cyst, a cellular organization in which germ cells are tightly interconnected and surrounded by somatic cells. The cyst produces oocytes for follicle formation and is a hub for essential processes in meiosis and oocyte differentiation. However, the formation and organization of the cyst, and their contribution to oocyte production in vertebrates remain unclear. Here, we provide tools for three-dimensional and functional in vivo analyses of the germline cyst in the zebrafish ovary. We describe the use of serial block-face scanning electron microscopy (SBF-SEM) to resolve the three-dimensional architecture of cells and organelles in the cyst at ultrastructural resolution. We present a deep learning-based pipeline for high-throughput quantitative analysis of three-dimensional confocal datasets of cysts in vivo. We provide a method for laser ablation of cellular components for manipulating cyst cells in ovaries. These methods will facilitate the investigation of the cyst cellular organization, expand the toolkit for the study of the zebrafish ovary, and advance our understanding of female developmental reproduction. They could also be further applied to the investigation of other developmental systems.


Asunto(s)
Oogénesis , Pez Cebra , Animales , Femenino , Oocitos , Ovario , Células Germinativas/ultraestructura
3.
Proc Natl Acad Sci U S A ; 120(27): e2301956120, 2023 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-37364115

RESUMEN

The energy needed to deform an elastic solid may be recovered, while in Newtonian fluids, like water and glycerol, deformation energy dissipates on timescales of the intermolecular relaxation time [Formula: see text] . For times considerably longer than [Formula: see text] the existence of shear elasticity requires long-range correlations, which challenge our understanding of the liquid state. We investigated laser-driven free surface bubbles in liquid glycerol by analyzing their expansion and bursting dynamics, in which we found a flow-dominating, rubber-like elasticity unrelated to surface tension forces. In extension to findings of a measurable liquid elasticity at even very low deformation frequencies [L. Noirez, P. Baroni, J. Mol. Struct. 972, 16-21 (2010), A. Zaccone, K. Trachenko, Proc. Natl. Acad. Sci. U.S.A. 117, 19653-19655 (2020)], that is difficult to access under increased strain, we find a robust, strain rate driven elasticity. The recovery of deformation energy allows the bursting bubble to reach Taylor-Culick velocities 20-fold higher than expected. The elasticity is persistent for microseconds, hence four orders of magnitude longer than [Formula: see text] . The dynamic shows that this persistence cannot originate from the far tail of a distribution of relaxation times around [Formula: see text] but must appear by frustrating the short molecular dissipation. The longer time should be interpreted as a relaxation of collective modes of metastable groups of molecules. With strain rates of 106 s-1, we observe a metastable glycerol shell exhibiting a rubber-like solid behavior with similar elasticity values and characteristic tolerance toward large strains, although the molecular interaction is fundamentally different.

4.
Development ; 149(16)2022 08 15.
Artículo en Inglés | MEDLINE | ID: mdl-35993388

RESUMEN

Cell and developmental biology increasingly require live imaging of protein dynamics in cells, tissues or living organisms. Thanks to the discovery and development of a panel of fluorescent proteins over the last decades, live imaging has become a powerful and commonly used approach. However, multicolor live imaging remains challenging. The generation of long Stokes shift red fluorescent proteins offers interesting new perspectives to bypass this limitation. Here, we provide a detailed characterization of mBeRFP for in vivo live imaging and its applications in Drosophila. Briefly, we show that a single illumination source is sufficient to stimulate mBeRFP and GFP simultaneously. We demonstrate that mBeRFP can be easily combined with classical green and red fluorescent proteins without any crosstalk. We also show that the low photobleaching of mBeRFP is suitable for live imaging, and that this protein can be used for quantitative applications, such as FRAP or laser ablation. Finally, we believe that this fluorescent protein, with the set of new possibilities it offers, constitutes an important tool for cell, developmental and mechano-biologists in their current research.


Asunto(s)
Proteínas Luminiscentes , Proteínas Fluorescentes Verdes , Proteínas Luminiscentes/genética , Proteínas Luminiscentes/metabolismo , Microscopía Confocal/métodos , Microscopía Fluorescente/métodos , Fotoblanqueo
5.
FASEB J ; 38(8): e23585, 2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38661043

RESUMEN

Fractional laser ablation is a technique developed in dermatology to induce remodeling of skin scars by creating a dense pattern of microinjuries. Despite remarkable clinical results, this technique has yet to be tested for scars in other tissues. As a first step toward determining the suitability of this technique, we aimed to (1) characterize the response to microinjuries in the healthy and cirrhotic liver, and (2) determine the underlying cause for any differences in response. Healthy and cirrhotic rats were treated with a fractional laser then euthanized from 0 h up to 14 days after treatment. Differential expression was assessed using RNAseq with a difference-in-differences model. Spatial maps of tissue oxygenation were acquired with hyperspectral imaging and disruptions in blood supply were assessed with tomato lectin perfusion. Healthy rats showed little damage beyond the initial microinjury and healed completely by 7 days without scarring. In cirrhotic rats, hepatocytes surrounding microinjury sites died 4-6 h after ablation, resulting in enlarged and heterogeneous zones of cell death. Hepatocytes near blood vessels were spared, particularly near the highly vascularized septa. Gene sets related to ischemia and angiogenesis were enriched at 4 h. Laser-treated regions had reduced oxygen saturation and broadly disrupted perfusion of nodule microvasculature, which matched the zones of cell death. Our results demonstrate that the cirrhotic liver has an exacerbated response to microinjuries and increased susceptibility to ischemia from microvascular damage, likely related to the vascular derangements that occur during cirrhosis development. Modifications to the fractional laser tool, such as using a femtosecond laser or reducing the spot size, may be able to prevent large disruptions of perfusion and enable further development of a laser-induced microinjury treatment for cirrhosis.


Asunto(s)
Isquemia , Cirrosis Hepática , Animales , Ratas , Cirrosis Hepática/metabolismo , Cirrosis Hepática/patología , Masculino , Isquemia/metabolismo , Isquemia/patología , Hígado/metabolismo , Hígado/patología , Terapia por Láser/métodos , Ratas Sprague-Dawley , Hepatocitos/metabolismo
6.
Proc Natl Acad Sci U S A ; 119(39): e2208830119, 2022 09 27.
Artículo en Inglés | MEDLINE | ID: mdl-36122203

RESUMEN

Recent developments in the area of resonant dielectric nanostructures have created attractive opportunities for concentrating and manipulating light at the nanoscale and the establishment of the new exciting field of all-dielectric nanophotonics. Transition metal dichalcogenides (TMDCs) with nanopatterned surfaces are especially promising for these tasks. Still, the fabrication of these structures requires sophisticated lithographic processes, drastically complicating application prospects. To bridge this gap and broaden the application scope of TMDC nanomaterials, we report here femtosecond laser-ablative fabrication of water-dispersed spherical TMDC (MoS2 and WS2) nanoparticles (NPs) of variable size (5 to 250 nm). Such NPs demonstrate exciting optical and electronic properties inherited from TMDC crystals, due to preserved crystalline structure, which offers a unique combination of pronounced excitonic response and high refractive index value, making possible a strong concentration of electromagnetic field in the NPs. Furthermore, such NPs offer additional tunability due to hybridization between the Mie and excitonic resonances. Such properties bring to life a number of nontrivial effects, including enhanced photoabsorption and photothermal conversion. As an illustration, we demonstrate that the NPs exhibit a very strong photothermal response, much exceeding that of conventional dielectric nanoresonators based on Si. Being in a mobile colloidal state and exhibiting superior optical properties compared to other dielectric resonant structures, the synthesized TMDC NPs offer opportunities for the development of next-generation nanophotonic and nanotheranostic platforms, including photothermal therapy and multimodal bioimaging.


Asunto(s)
Nanosferas , Medicina de Precisión , Refractometría , Molibdeno , Nanosferas/uso terapéutico , Medicina de Precisión/instrumentación , Agua
7.
Proc Natl Acad Sci U S A ; 119(17): e2110245119, 2022 04 26.
Artículo en Inglés | MEDLINE | ID: mdl-35446704

RESUMEN

Efforts to understand the phenotypic transition that gave rise to maize from teosinte have mainly focused on the analysis of aerial organs, with little insights into possible domestication traits affecting the root system. Archeological excavations in San Marcos cave (Tehuacán, Mexico) yielded two well-preserved 5,300 to 4,970 calibrated y B.P. specimens (SM3 and SM11) corresponding to root stalks composed of at least five nodes with multiple nodal roots and, in case, a complete embryonic root system. To characterize in detail their architecture and anatomy, we used laser ablation tomography to reconstruct a three-dimensional segment of their nodal roots and a scutellar node, revealing exquisite preservation of the inner tissue and cell organization and providing reliable morphometric parameters for cellular characteristics of the stele and cortex. Whereas SM3 showed multiple cortical sclerenchyma typical of extant maize, the scutellar node of the SM11 embryonic root system completely lacked seminal roots, an attribute found in extant teosinte and in two specific maize mutants: root with undetectable meristem1 (rum1) and rootless concerning crown and seminal roots (rtcs). Ancient DNA sequences of SM10­a third San Marcos specimen of equivalent age to SM3 and SM11­revealed the presence of mutations in the transcribed sequence of both genes, offering the possibility for some of these mutations to be involved in the lack of seminal roots of the ancient specimens. Our results indicate that the root system of the earliest maize from Tehuacán resembled teosinte in traits important for maize drought adaptation.


Asunto(s)
Domesticación , Zea mays , México , Fenotipo , Zea mays/genética
8.
Development ; 148(18)2021 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-34132346

RESUMEN

In many species, leaves are initiated at the flanks of shoot meristems. Subsequent growth usually occurs mainly in the plane of the leaf blade, which leads to the formation of a bifacial leaf with dorsoventral identities. In a classical set of surgical experiments in potato meristems, Sussex provided evidence that dorsoventrality depends on a signal emanating from the meristem center. Although these results could be reproduced in tomato, this concept has been debated. We revisited these experiments in Arabidopsis, in which a range of markers are available to target the precise site of ablation. Using specific markers for organ founder cells and dorsoventral identity, we were unable to perturb the polarity of leaves and sepals long before organ outgrowth. Although results in Solanaceae suggested that dorsoventral patterning was unstable during early development, we found that, in Arabidopsis, the local information contained within and around the primordium is able to withstand major invasive perturbations, long before polarity is fully established.


Asunto(s)
Arabidopsis/fisiología , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Regulación de la Expresión Génica de las Plantas/fisiología , Ácidos Indolacéticos/metabolismo , Solanum lycopersicum/metabolismo , Solanum lycopersicum/fisiología , Meristema/metabolismo , Meristema/fisiología , Hojas de la Planta/metabolismo , Hojas de la Planta/fisiología
9.
Development ; 148(2)2021 01 26.
Artículo en Inglés | MEDLINE | ID: mdl-33376126

RESUMEN

The enteric nervous system (ENS), which is derived from neural crest, is essential for gut function, and its deficiency causes severe congenital diseases. Since the capacity for ENS regeneration in mammals is limited, additional complementary models would be useful. Here, we show that the ENS in zebrafish larvae at 10-15 days postfertilization is highly regenerative. After laser ablation, the number of enteric neurons recovered to ∼50% of the control by 10 days post-ablation (dpa). Using transgenic lines in which enteric neural crest-derived cells (ENCDCs) and enteric neurons are labeled with fluorescent proteins, we live imaged the regeneration process and found covering by neurites that extended from the unablated area and entry of ENCDCs into the ablated areas by 1-3 dpa. BrdU assays suggested that ∼80% of the enteric neurons and ∼90% of the Sox10-positive ENCDCs therein at 7 dpa were generated through proliferation. Thus, ENS regeneration involves proliferation, entrance and neurogenesis of ENCDCs. This is the first report regarding the regeneration process of the zebrafish ENS. Our findings provide a basis for further in vivo research at single-cell resolution in this vertebrate model.


Asunto(s)
Movimiento Celular , Sistema Nervioso Entérico/citología , Sistema Nervioso Entérico/fisiología , Regeneración Nerviosa , Cresta Neural/citología , Animales , Animales Modificados Genéticamente , Axones/metabolismo , Proliferación Celular , Proteínas Fluorescentes Verdes/metabolismo , Intestinos/inervación , Larva , Neuritas/metabolismo , Neurogénesis , Factores de Tiempo
10.
Small ; 20(40): e2403314, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39152932

RESUMEN

Efficient and durable electrocatalysts for the hydrogen evolution reaction (HER) in alkaline seawater environments are essential for sustainable hydrogen production. Zeolitic imidazolate framework-8 (ZIF-8) is synthesized through pulsed laser ablation in liquid, followed by pyrolysis, producing N-doped porous carbon (NC). NC matrix serves as a self-template, enabling Pt nanocluster decoration (NC-Pt) via pulsed laser irradiation in liquid. NC-Pt exhibits a large surface area, porous structure, high conductivity, N-rich carbon, abundant active sites, low Pt content, and a strong NC-Pt interaction. These properties enhance efficient mass transport during the HER. Remarkably, the optimized NC-Pt-4 catalyst achieves low HER overpotentials of 52, 57, and 53 mV to attain 10 mA cm-2 in alkaline, alkaline seawater, and simulated seawater, surpassing commercial Pt/C catalysts. In a two-electrode system with NC-Pt-4(-)ǀǀIrO2(+) as cathode and anode, it demonstrates excellent direct seawater electrolysis performance, with a low cell voltage of 1.63 mV to attain 10 mA cm-2 and remarkable stability. This study presents a rapid and efficient method for fabricating cost-effective and highly effective electrocatalysts for hydrogen production in alkaline and alkaline seawater environments.

11.
Small ; : e2403054, 2024 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-39073266

RESUMEN

Short carbon atomic wires, the prototypes of the lacking carbon allotrope carbyne, represent the fundamental 1D system and the first stage in carbon nanostructure growth, which still exhibits many open points regarding their growth and stability. An in situ UV resonance Raman approach is introduced for real-time monitoring of the growth of carbon atomic wires during pulsed laser ablation in liquid without perturbing the synthesis environment. Single-chain species' growth dynamics are tracked, achieving size selectivity by exploiting the peculiar optoelectronic properties of carbon wires and the tunability of synchrotron radiation. Diverse solvents are systematically explored, finding size- and solvent-dependent production rates linked to the solvent's C/H ratio and carbonization tendency. Carbon atomic wires' growth dynamics reveal a complex interplay between formation and degradation, leading to an equilibrium. Water, lacking in carbon atoms and reduced polyynes solubility, yields fewer wires with rapid saturation. Organic solvents exhibit enhanced productivity and near-linear growth, attributed to additional carbon from solvent dissociation and low relative polarity. Exploring the dynamics of the saturation regime provides new insights into advancing carbon atomic wires synthesis via PLAL. Understanding carbon atomic wires' growth dynamics can contribute to optimizing PLAL processes for nanomaterial synthesis.

12.
Small ; 20(42): e2403531, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-38874066

RESUMEN

For the initial instance, oxygen deficiency-enriched vanadium pentoxide (O─V2O5@500) thin film electrodes are tuned by the Pulsed Laser Ablation technique. The O─V2O5@500 thin film electrode shows remarkable electrochemical performances confirming the greater potential window of -0.4 to 0.9 V versus Hg/HgO in an alkaline electrolyte; also, the O─V2O5@ 500 thin film electrode exhibits a noteworthy volumetric capacity of 167.7 mAh cm-3 (areal capacity of 73.3 µAh cm-2). Additionally, Density Functional Theory (DFT) theory calculations are carried out for oxygen-deficient V2O5. From the partial density of states (pDOS) and partial charge density analysis, it is clear that oxygen vacancy improves the electrical conductivity due to the higher degree of electron delocalization of V─O─V near the vacancy and enhances the redox properties due to the formation of in-gap states. Further, it is reported that a O─V2O5@ 500 ||PVA-KOH|| Bi2O3 A-650 thin film supercapbattery (TFSCB) device attains an exceptional discharge volumetric capacitance of 182.85 F cm-3 (equal volumetric capacity of 124.5 mAh cm-3). Furthermore, the TFSCB device exhibits an extraordinary maximum volumetric energy (power) density of 14.28 mWh cm-3 (1.66 W cm-3); TFSCB succeeds in supreme capacity retention of 86% with outstanding coulombic efficiency of 94.4% after 21 000 cycles.

13.
Mass Spectrom Rev ; 42(5): 2234-2267, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37462443

RESUMEN

This Tutorial is to provide a summary of parameters useful for successful outcomes of laserspray ionization (LSI) and related methods that employ a laser to ablate a matrix:analyte sample to produce highly charged ions. In these methods the purpose of the laser is to transfer matrix-analyte clusters into the gas phase. Ions are hypothesized to be produced by a thermal process where emitted matrix:analyte gas-phase particles/clusters are charged and loss of matrix from the charged particles leads to release of the analyte ions into the gas phase. The thermal energy responsible for the charge-separation process is relatively low and not necessarily supplied by the laser; a heated inlet tube linking atmospheric pressure with the first vacuum stage of a mass spectrometer is sufficient. The inlet becomes the "ion source", and inter alia, pressure, temperature, and the matrix, which can be a solid, liquid, or combinations, become critical parameters. Injecting matrix:analyte into a heated inlet tube using laser ablation, a shockwave, or simply tapping, all produce the similar mass spectra. Applications are provided that showcase new opportunities in the field of mass spectrometry.

14.
Chemphyschem ; : e202400486, 2024 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-39022857

RESUMEN

The development of peroxidase mimic nanocatalysts is relevant for oxidation reactions in biosensing, environmental monitoring and green chemical processes. Several nanomaterials have been proposed as peroxidase mimic, the majority of which consists of noble metals and oxide nanoparticles (NPs). Yet, there is still limited information about how the change in the composition influences their catalytic activity. Here, the peroxidase mimic behaviour of gold NPs is compared to a traditional nanoalloy as Au-Ag and to the Au-Fe and the Au-Co nanoalloys, which were not tested before as oxidation catalysis. Since the alloys of gold with iron and cobalt are thermodynamically unstable, laser ablation in liquid (LAL) is exploited for the synthesis of these NPs. Using LAL, no chemical stabilizers or capping agents are present on the NPs surface, allowing the evaluation of the oxidation behaviour as a function of the alloy composition. The results point to the importance of surface gold atoms in the catalytic process, but also indicate the possibility of obtaining active nanocatalysts with a lower content of Au by alloying it with iron, which is earth-abundant, non-toxic and low cost. Overall, Au nanoalloys are worth consideration as a more sustainable alternative to pure Au nanocatalysts for oxidation reactions.

15.
Chemphyschem ; 25(15): e202400191, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-38703034

RESUMEN

Herein, we report a spectroscopic study of N-acetyl-L-cysteine, an important antioxidant drug, using Fourier-transform microwave techniques and in isolated conditions. Two conformers are observed, where most stable structure adopts a cis disposition, and the second conformer has a lower abundance and adopts a trans disposition. The rotational constants and the barriers to methyl internal rotation are determined for each conformer, allowing a precise conformation identification. The results show that the cis form adopts an identical structure in the crystal, solution, and gas phases. Additionally, the structures are contrasted against those of cysteine.


Asunto(s)
Acetilcisteína , Acetilcisteína/química , Cisteína/química , Rotación , Análisis Espectral/métodos , Conformación Molecular , Microondas
16.
Chemphyschem ; : e202400121, 2024 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-39132832

RESUMEN

Surfactant-free nanoparticles can be adsorbed on a support material by electrostatic deposition which requires electrostatic attraction between the nanoparticles and the support material. However, when nanoparticles and support have a similar isoelectric point (IEP), it is difficult to create such electrostatically attractive conditions and trigger the adsorption process by pH adjustment. In this work, we present an alternative approach to support laser-generated metal nanoparticles by controlled precipitation onto thin graphene oxide (GO) nanosheets via a kinetically barrierless process induced by high ionic strength. This enables supporting the nanoparticles on the GO sheets with a uniform distribution even though they share a similar IEP. The broad applicability of this method is demonstrated by using different metals, nanoparticle diameters, and mass loadings. In summary, this approach allows supporting nanoparticles regardless of their surface charge.

17.
Artículo en Inglés | MEDLINE | ID: mdl-39189066

RESUMEN

BACKGROUND: Redo-transcatheter aortic valve replacement (TAVR) is a promising treatment for transcatheter aortic valve degeneration, becoming increasingly relevant with an aging population. In redo-TAVR, the leaflets of the initial (index) transcatheter aortic valve (TAV) are displaced vertically when the second TAV is implanted, creating a cylindrical cage that can impair coronary cannulation and flow. Preventing coronary obstruction and maintaining coronary access is essential, especially in young and low-risk patients undergoing TAVR. This study aimed to develop a new leaflet modification strategy using laser ablation to prevent coronary obstruction and facilitate coronary access after repeat TAVR. METHODS: To evaluate the feasibility of the leaflet modification technique using laser ablation, the initial phase of this study involved applying a medical-grade ultraviolet laser for ablation through pericardial tissue. Following this intervention, computational fluid dynamics simulations were utilized to assess the efficacy of the resulting perforations in promoting coronary flow. These simulations played a crucial role in understanding the impact of the modifications on blood flow patterns, ensuring these changes would facilitate the restoration of coronary circulation. RESULTS: Laser ablation of pericardium leaflets was successful, demonstrating the feasibility of creating openings in the TAV leaflets. Flow simulation results show that ablation of index valve leaflets can effectively mitigate the flow obstruction caused by sinus sequestration in redo-TAVR, with the extent of restoration dependent on the number and location of the ablated openings. CONCLUSIONS: Laser ablation could be a viable method for leaflet modification in redo-TAVR, serving as a new tool in interventional procedures.

18.
Am J Obstet Gynecol ; 231(3): 365.e1-365.e15, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38897340

RESUMEN

BACKGROUND: Intraoperative blood transfer between twins during laser surgery for twin-twin transfusion syndrome can vary by surgical technique and has been proposed to explain differences in donor twin survival. OBJECTIVE: This trial compared donor twin survival with 2 laser techniques: the sequential technique, in which the arteriovenous communications from the volume-depleted donor to the volume-overloaded recipient are laser-occluded before those from recipient to donor, and the selective technique, in which the occlusion of the vascular communications is performed in no particular order. STUDY DESIGN: A single-center, open-label, randomized controlled trial was conducted in which twin-twin transfusion syndrome patients were randomized to sequential vs selective laser surgery. Nested within the trial, a second trial randomized patients with superficial anastomoses (arterioarterial and venovenous) to ablation of these connections first (before ablating the arteriovenous anastomoses) vs last. The primary outcome measure was donor twin survival at birth. RESULTS: A total of 642 patients were randomized. Overall donor twin survival was similar between the 2 groups (274 of 320 [85.6%] vs 271 of 322 [84.2%]; odds ratio, 1.12 [95% confidence interval, 0.73-1.73]; P=.605). Superficial anastomoses occurred in 177 of 642 cases (27.6%). Donor survival was lower in the superficial anastomosis group vs those with only arteriovenous communications (125 of 177 [70.6%] vs 420 of 465 [90.3%]; adjusted odds ratio, 0.33 [95% confidence interval, 0.20-0.54]; P<.001). In cases with superficial anastomoses, donor survival was independent of the timing of ablation or surgical technique. The postoperative mean middle cerebral artery peak systolic velocity was lower in the sequential vs selective group (1.00±0.30 vs 1.06±0.30 multiples of the median; P=.003). Post hoc analyses showed 2 factors that were associated with poor overall donor twin survival: the presence or absence of donor twin preoperative critical abnormal Doppler parameters and the presence or absence of arterioarterial anastomoses. Depending on these factors, 4 categories of patients resulted: (1) Category 1 (347 of 642 [54%]), no donor twin critical abnormal Doppler + no arterioarterial anastomoses: donor twin survival was 91.2% in the sequential and 93.8% in the selective groups; (2) Category 2 (143 of 642 [22%]), critical abnormal Doppler present + no arterioarterial anastomoses: donor survival was 89.9% vs 75.7%; (3) Category 3 (73 of 642 [11%]), no critical abnormal Doppler + arterioarterial anastomoses present: donor survival was 94.7% vs 74.3%; and (4) Category 4 (79 of 642 [12%]), critical abnormal Doppler present + arterioarterial anastomoses present: donor survival was 47.6% vs 64.9%. CONCLUSION: Donor twin survival did not differ between the sequential vs selective laser techniques and did not differ if superficial anastomoses were ablated first vs last. The donor twin's postoperative middle cerebral artery peak systolic velocity was improved with the sequential vs the selective approach. Post hoc analyses suggest that donor twin survival may be associated with the choice of laser technique according to high-risk factors. Further study is needed to determine whether using these categories to guide the choice of surgical technique will improve outcomes.


Asunto(s)
Transfusión Feto-Fetal , Terapia por Láser , Humanos , Transfusión Feto-Fetal/cirugía , Femenino , Embarazo , Terapia por Láser/métodos , Adulto , Anastomosis Arteriovenosa
19.
World J Urol ; 42(1): 35, 2024 Jan 13.
Artículo en Inglés | MEDLINE | ID: mdl-38217727

RESUMEN

PURPOSE: Past decade has seen a renewed interest in minimally invasive surgical techniques (MISTs) for management of enlarged prostate. This narrative review aims to explore newer MIST for benign prostatic hyperplasia (BPH) which are not yet integrated into established societal guidelines. METHODS: We conducted a literature search across PubMed, Google Scholar, and FDA ClinicalTrials.gov databases on June 1st, 2023, to identify studies published within the past decade exploring various MISTs for BPH. Additionally, we gathered insights from abstracts presented in meetings of professional associations and corporate websites. We broadly classified these procedures into three distinct categories: energy-based, balloon dilation, and implant/stent treatments. We collected detail information about the device, procedure details, its inclusion and exclusion criteria, and outcome. RESULTS: Our review reveals that newer energy-based MISTs include Transperineal Laser Ablation, Transurethral Ultrasound Ablation, and High-Intensity Focused Ultrasound. In the sphere of balloon dilation, Transurethral Columnar Balloon Dilation and the Optilume BPH Catheter System were gaining momentum. The noteworthy implants/stents that are on horizon include Butterfly Prostatic Retraction Device, Urocross Expander System, Zenflow Spring System, and ProVee Urethral Expander System. CONCLUSION: The exploration of various MISTs reflects ongoing efforts to enhance patient care and address limitations of existing treatments. This review provides a bird-eye view and valuable insights for urologists and researchers seeking to navigate the dynamic landscape of MISTs in the quest for effective and minimally invasive solutions for enlarged prostates.


Asunto(s)
Hiperplasia Prostática , Resección Transuretral de la Próstata , Masculino , Humanos , Hiperplasia Prostática/cirugía , Próstata/cirugía , Resección Transuretral de la Próstata/métodos , Prostatectomía/métodos , Procedimientos Quirúrgicos Mínimamente Invasivos , Stents
20.
World J Urol ; 42(1): 402, 2024 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-38985193

RESUMEN

PURPOSE: Transperineal laser ablation (TPLA) is a new minimally-invasive surgical treatment for patients with benign prostatic obstruction (BPO). We report the perioperative and mid-term functional results of the first 100 consecutively patients undergoing TPLA at our institution. METHODS: Clinical data from consecutive patients undergoing TPLA at our institution from April 2021 to July 2023 were prospectively collected. Primary endpoints were the postoperative changes in IPSS, QoL and MSHQ 3-item questionnaires and in Qmax and post-void residual volume (PVR). RESULTS: Overall, 100 consecutive patients underwent the procedure. Median age and prostate volume were 66 (IQR 60-75) years and 50 (IQR 40-70) ml, respectively. In the cohort, 14 (14%) patients had an indwelling catheter and 81 (81%) were under oral BPO therapy at the time of TPLA. Baseline median Qmax (ml/s) and PVR (ml) were 9.1 (IQR 6.9-12) and 90 (IQR 50-150), respectively, while median IPSS and QoL were 18 (IQR 15-23) and 4 (IQR 3-4). At all the follow-up timepoints, the evaluated outcomes on both symptoms and functional parameters showed a statistically significant improvement (p < 0.001). Antegrade ejaculation was preserved in all sexually active patients. No postoperative Clavien-Dindo > 2 complications were recorded. CONCLUSIONS: TPLA represents a safe option for selected well-informed patients swith LUTS due to BPO. Our prospective study confirms the feasibility and favorable perioperative and functional outcomes in a real-world cohort with heterogenous prostate volumes and patient characteristics.


Asunto(s)
Terapia por Láser , Hiperplasia Prostática , Humanos , Masculino , Hiperplasia Prostática/cirugía , Hiperplasia Prostática/complicaciones , Anciano , Persona de Mediana Edad , Terapia por Láser/métodos , Estudios Prospectivos , Resultado del Tratamiento , Perineo/cirugía , Estudios de Cohortes
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA