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1.
Medicine (Baltimore) ; 101(28): e29489, 2022 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-35839028

RESUMO

We aimed to evaluate associated factors for point-of-care ultrasound (POCUS)-guided percutaneous catheterization for venoarterial extracorporeal membrane oxygenation (VA-ECMO). VA-ECMO cases from March 2018 to October 2020 in Department of Intensive Care Unit, Binhaiwan Central Hospital of Dongguan, were enrolled. Clinical data, outcomes, and complications were recorded and summarized. Fifty-nine cases were enrolled, among which 88.1% succeeded in POCUS-guided catheterization via Seldinger technique, whereas 59.3% succeeded at the first puncture. Results showed that artery diameter and times of arterial punctures were independent associated factors for Seldinger puncture (P = .018, odds ratio [OR] = 23.374, 95% confidence interval [CI] = 1.706-320.270; P = .031, OR = 145.098, 95% CI = 1.592-13220.980), and artery diameter and cardiac ejection fraction value (≥30%/<30%) were independent associated factors for first puncture (P = .044, OR = 1.622, 95% CI = 1.014-2.596; P = .013, OR = 5.565, 95% CI = 1.441-21.488). For extracorporeal cardiopulmonary resuscitation patients, artery diameter was independent associated factor for Seldinger puncture (P = .022, OR = 2.070, 95% CI = 1.110-3.858), and cardiac ejection fraction value (≥30%/<30%) was independent associated factor for first puncture (P = .007, OR = 9.533, 95% CI = 1.847-49.204). Thirteen patients (22.0%) had local hemorrhage post puncture, 8 patients (13.6%) presented distal limb arterial ischemia, and 8 patients (13.6%) suffered puncture-related thrombosis. Vasoactive Inotropic Score was found to be independent associated factor for local hemorrhage (P = .039, OR = 0.994, 95% CI = 0.988-1.000), and the Acute Physiology and Chronic Health Evaluation II score was independent associated factor for thrombosis (P = .025, OR = 0.935, 95% CI = 0.882-0.992). Diabetes and cardiopulmonary resuscitation time before catheterization were independent factors for distal limb ischemia (P = .026, OR = 220.774, 95% CI = 1.905-25591.327; P = .017, OR = 1.054, 95% CI = 1.009-1.101). POCUS-guided percutaneous catheterization via Seldinger technique can be the first choice for VA-ECMO cannulation, especially for a team without angiotomy qualifications. Before cannulation, evaluating the target artery and heart function by ultrasound can help predict outcome of catheterization. Assessing risk factors (diabetes, cardiopulmonary resuscitation time before catheterization, Vasoactive Inotropic Score, the Acute Physiology and Chronic Health Evaluation II score) is helpful for prevention and treatment of complications.


Assuntos
Cateterismo Periférico , Oxigenação por Membrana Extracorpórea , Doenças Vasculares Periféricas , Trombose , Cateterismo/efeitos adversos , Cateterismo/métodos , Cateterismo Periférico/efeitos adversos , Oxigenação por Membrana Extracorpórea/efeitos adversos , Oxigenação por Membrana Extracorpórea/métodos , Artéria Femoral , Humanos , Isquemia/etiologia , Doenças Vasculares Periféricas/etiologia , Estudos Retrospectivos , Trombose/etiologia
2.
Ann Transl Med ; 9(18): 1431, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34733983

RESUMO

BACKGROUND: While serum hepatitis B surface antigens (HBsAg) play an important role in the diagnosis and assessment of treatment results of hepatitis B virus (HBV) infections, it remains unclear whether HBsAg levels normalized to hepatic parenchymal cell volume (HPCV) is a superior indicator of disease state. This study compared the absolute and HPCV-normalized serum HBsAg levels in hepatitis B e antigen (HBeAg)-positive and HBeAg-negative patients with chronic hepatitis B (CHB). METHODS: Patients admitted to our institution with CHB were retrospectively included and categorized into the HBeAg-positive and HBeAg-negative groups. HPCV was calculated based on pathological examination of liver biopsy specimens and theory of sphere geometry. The difference between HBsAg levels and HBsAg normalized to HPCV, and also correlation between HBsAg levels and liver inflammation and fibrosis was analyzed. RESULTS: Absolute HBsAg levels (P=0.004), but not HPCV-normalized HBsAg levels (P=0.071) were significantly higher in HBeAg-positive patients compared to HBeAg-negative patients. In HBeAg-positive CHB patients, absolute HBsAg levels were positively correlated with liver inflammation grade (R=0.285, P=0.001) and hepatic fibrosis stage (R=0.351, P<0.001), as were HPCV-normalized HBsAg levels (R=0.640 and 0.742, both, P<0.001). However, in HBeAg-negative CHB patients, only HPCV-normalized HBsAg level were correlated with liver inflammation grade and hepatic fibrosis stage (R=0.640 and 0.785, both, P<0.001). CONCLUSIONS: HPCV-normalized serum HBsAg levels, rather than absolute HBsAg levels, were positively correlated with liver inflammation grade and hepatic fibrosis stage in both HBeAg-positive and HBeAg-negative CHB patients. Thus, HPCV-normalized HBsAg levels may more accurately reflect the pathological progress of CHB patients compared to absolute HBsAg levels.

3.
J Phys Chem Lett ; 12(13): 3373-3378, 2021 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-33784108

RESUMO

Coexistence of rotationally π-π stacked columns and discrete slip-stacked dimers of perylene bisimide (PBI) chromophores is revealed by single crystal X-ray diffraction in the lamellar crystal of a head-to-tail linked PBI dyad. The rotary π-π stacked columnar moieties show H-type spectral character with relatively higher excitation energy, while the discrete slip-stacked π-π dimers have J-type spectral behavior with lower excitation energy. The lamellar crystals show relatively low photoluminescence efficiency of 12% at room temperature, while this dramatically increases to ∼90% at low temperature (80 K). Both of the rotary and slip-stacked moieties are emissive, and the nonradiative energy transfer processes between them are suppressed at low temperature, ensuring the highly efficient excimer-like long-lived fluorescence.

4.
Respir Med Case Rep ; 32: 101343, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33614405

RESUMO

Hypervirulent Klebsiella pneumoniae (hvKP) can cause lung abscess, serious infection, and has a high mortality. Drainage plays a key role in the treatment of lung abscess secondary to hvKP. Contrast-enhanced ultrasound (CEUS) can identify necrotic areas within peripheral pulmonary lesions. We report a case in which thoracic CEUS using solution of sulfur hexafluoride microbubbles (SonoVue®, Bracco, Milan, Italy) was better than computed tomography (CT) in depicting lung abscess from consolidation secondary to hvKP, and its role in guiding drainage of lung abscess. CEUS is a promising imaging technique for confirming an appropriate time for drainage of lung abscess secondary to hvKP, for point-of-care application in critical patients with impaired renal function which may be aggravated by CT contrast medium.

5.
Updates Surg ; 73(2): 481-494, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33048340

RESUMO

Laparoscopic cholecystectomy and percutaneous transhepatic gallbladder drainage (PTGBD) are common treatments for patients with acute cholecystitis. However, the safety and efficacy of emergency laparoscopic cholecystectomy (ELC) and delayed laparoscopic cholecystectomy (DLC) after PTGBD in patients with acute cholecystitis remain unclear. The PubMed, EMBASE, and Cochrane Library databases were searched through October 2019. The quality of the included nonrandomized studies was assessed using the Methodological Index for Nonrandomized Studies (MINORS). The meta-analysis was performed using STATA version 14.2. A random-effects model was used to calculate the outcomes. A total of fifteen studies involving 1780 patients with acute cholecystitis were included in the meta-analysis. DLC after PTGBD was associated with a shorter operative time (SMD - 0.51; 95% CI - 0.89 to - 0.13; P = 0.008), a lower conversion rate (RR 0.43; 95% CI 0.26 to 0.69; P = 0.001), less intraoperative blood loss (SMD - 0.59; 95% CI - 0.96 to - 0.22; P = 0.002) and longer time of total hospital stay compared to ELC (SMD 0.91; 95% CI 0.57-1.24; P < 0.001). There was no difference in the postoperative complications (RR 0.68; 95% CI 0.48-0.97; P = 0.035), biliary leakage (RR 0.65; 95% CI 0.34-1.22; P = 0.175) or mortality (RR 1.04; 95% CI 0.39-2.80; P = 0.933). Compared to ELC, DLC after PTGBD had the advantages of a shorter operative time, a lower conversion rate and less intraoperative blood loss.


Assuntos
Colecistectomia Laparoscópica , Colecistite Aguda , Colecistectomia , Colecistite Aguda/cirurgia , Drenagem , Humanos , Estudos Retrospectivos , Resultado do Tratamento
6.
ACS Appl Mater Interfaces ; 12(41): 46340-46347, 2020 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-32964705

RESUMO

Inverted-structure perovskite solar cells (PVSCs) applying NiOx as the hole transport layer (HTL) have attracted increasing attention. It is still a challenge to optimize the contact between NiOx and the perovskite layer and to suppress energy loss at the interface. In this study, interface engineering was carried out by modifying the NiOx layer with different polymers such as polystyrene, poly(methyl methacrylate) (PMMA), or poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine] (PTAA) to improve the surface contact between NiOx and the perovskite, to decrease the defect states, and to make the energy level alignment better. The NiOx/PMMA-based device presents a Voc as high as 1.19 V because of the improved interfacial contact and the interaction of the carbonyl and methoxy group with Pb2+. The NiOx/PTAA-based device with the structure ITO/NiOx/PTAA/(MAPbI3)0.95(MAPbBr2Cl)0.05/PCBM/BCP/Ag exhibits the highest power conversion efficiency of 21.56% with a high Voc of 1.19 V. The enhanced performance can be attributed to the deepened highest occupied molecular orbital level of NiOx/PTAA, which matched well with that of the perovskite and suppressed interface energy loss as well. This work provides a facile approach for efficiently improving the Voc of NiOx-based PVSCs.

7.
Adv Mater ; 31(25): e1901284, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31038236

RESUMO

Mixed perovskites have achieved substantial successes in boosting solar cell efficiency, but the complicated perovskite crystal formation pathway remains mysterious. Here, the detailed crystallization process of mixed perovskites (FA0.83 MA0.17 Pb(I0.83 Br0.17 )3 ) during spin-coating is revealed by in situ grazing-incidence wide-angle X-ray scattering measurements, and three phase-formation stages are identified: I) precursor solution; II) hexagonal δ-phase (2H); and III) complex phases including hexagonal polytypes (4H, 6H), MAI-PbI2 -DMSO intermediate phases, and perovskite α-phase. The correlated device performance and ex situ characterizations suggest the existence of an "annealing window" covering the duration of stage II. The spin-coated film should be annealed within the annealing window to avoid the formation of hexagonal polytypes during the perovskite crystallization process, thus achieving a good device performance. Remarkably, the crystallization pathway can be manipulated by incorporating Cs+ ions in mixed perovskites. Combined with density functional theory calculations, the perovskite system with sufficient Cs+ will bypass the formation of secondary phases in stage III by promoting the formation of α-phase both kinetically and thermodynamically, thereby significantly extending the annealing window. This study provides underlying reasons of the time sensitivity of fabricating mixed-perovskite devices and insightful guidelines for manipulating the perovskite crystallization pathways toward higher performance.

8.
Angew Chem Int Ed Engl ; 58(28): 9409-9413, 2019 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-31066152

RESUMO

The fabrication of high-quality film with large grains oriented along the direction of film thickness is important for 2D Ruddlesden-Popper perovskite-based solar cells (PVSCs). High-quality 2D BA2 MAn-1 Pbn I3n+1 (BA+ =butylammonium, MA+ =methylammonium, n=5) perovskite films were fabricated with a grain size of over 1 µm and preferential orientation growth by introducing a second spacer cation (SSC+ ) into the precursor solution. Dynamic light scattering showed that SSC+ addition can induce aggregation in the precursor solution. The precursor aggregates are favorable for the formation of large crystal grains by inducing nucleation and decreasing the nucleation sites. Applying phenylethylammonium as SSC+ , the optimized inverted planar PVSCs presented a maximum PCE of 14.09 %, which is the highest value of the 2D BA2 MAn-1 Pbn I3n+1 (n=5) PVSCs. The unsealed device shows good moisture stability by maintaining around 90 % of its initially efficiency after 1000 h exposure to air (Hr=25±5 %).

9.
Small ; 14(39): e1802349, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30168671

RESUMO

Ultraviolet-visible-near infrared (UV-Vis-NIR) broadband detection is important for image sensing, communication, and environmental monitoring, yet remains as a challenge in achieving high external quantum efficiency (EQE) in the broad spectrum range. Herein, sensitive broadband integrated photodetectors (PDs) with high EQE levels are reported. The organic bulk-heterojunction (OBHJ) layer, based on a NIR sensitive organic acceptor, is employed to extend the response spectrum of the perovskite PDs. A key strategy of introducing dual electron transport materials respectively for Vis and NIR regions into the active layer of integrated PDs is applied. Further combined with the proper energy level alignment and reasonable distribution of PC61 BM in the active layer, the extraction and transport of photo induced charges in between perovskite and OBHJ is promoted efficiently. The integrated PD with the optimized structure exhibits an EQE mostly beyond 70% in the Vis-NIR region, which is the highest value among the ever reported solution-processable broadband PDs. The highest responsivity is 0.444 and 0.518 A W-1 in the Vis and NIR region, respectively. The specific detectivity is beyond 1010 Jones in the range from 340 to 940 nm, enabling the device to detect weak signals in the UV to NIR broad region.

10.
Adv Mater ; 28(44): 9729-9734, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27634640

RESUMO

Small-molecule nonfullerene-based tandem organic solar cells (OSCs) are fabricated for the first time by utilizing P3HT:SF(DPPB)4 and PTB7-Th:IEIC bulk heterojunctions as the front and back subcells, respectively. A power conversion efficiency of 8.48% is achieved with an ultrahigh open-circuit voltage of 1.97 V, which is the highest voltage value reported to date among efficient tandem OSCs.

11.
ACS Appl Mater Interfaces ; 8(32): 20916-27, 2016 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-27434658

RESUMO

Four different polymorphic conformations of diethyl 5,5'-[5,5'-[2,5-bis(2-ethylhexyl)-3,6-dioxo-2,3,5,6-tetrahydropyrrolo[3,4-c]pyrrole-1,4-diyl]bis(thiophene-5,2-diyl)]difuran-2-carboxylate (DPP-(CF)2), namely, DPP-(CF)2-α, DPP-(CF)2-ß, DPP-(CF)2-γ, and DPP-(CF)2-ω, were identified from X-ray diffraction analysis conducted on their thin films and single crystals. Highly crystalline and well-textured thin films of these four polymorphs were successfully prepared via postgrowth solvent vapor and thermal annealing treatments to investigate the polymorphic phase-dependent optical and electrical properties of DPP-(CF)2. Interestingly, during the phase transition from DPP-(CF)2-α to DPP-(CF)2-ω, the optical band gap decreases from 1.75 to 1.5 eV because of the enhanced π-π interaction between the neighboring molecules. Except for DPP-(CF)2-γ, the other three phases show ambipolar charge transport. Although DPP-(CF)2-ß and DPP-(CF)2-γ exhibit a similar way of packing, a small increment in the π-π-stacking distance (0.006 Å) and twist conformation of the grafted electron-donating moieties of DPP-(CF)2-γ are found to reduce its hole mobility.

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