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1.
Transfusion ; 64(4): 606-614, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38511889

RESUMO

BACKGROUND: The CONvalescent Plasma for Hospitalized Adults With COVID-19 Respiratory Illness (CONCOR-1) trial was a multicenter randomized controlled trial assessing convalescent plasma in hospitalized COVID-19 patients. This study evaluates the cost-effectiveness of convalescent plasma and its impact on quality-of-life to provide insight into its potential as an alternative treatment in resource-constrained settings. METHODS: Individual patient data on health outcomes and resource utilization from the CONCOR-1 trial were used to conduct the analysis from the Canadian public payer's perspective with a time horizon of 30 days post-randomization. Baseline and 30-day EQ-5D-5L were measured to calculate quality-adjusted survival. All costs are presented in 2021 Canadian dollars. The base case assessed the EQ-5D-5L scores of hospitalized inpatients reporting at both timepoints, and a utility score of 0 was assigned for patients who died within 30 days. Costs for all patients enrolled were used. The sensitivity analysis utilizes EQ-5D-5L scores from the same population but only uses costs from this population. RESULTS: 940 patients were randomized: 627 received CCP and 313 received standard care. The total costs were $28,716 (standard deviation, $25,380) and $24,258 ($22,939) for the convalescent plasma and standard care arms respectively. EQ-5D-5L scores were 0.61 in both arms (p = .85) at baseline. At 30 days, EQ-5D-5L scores were 0.63 and 0.64 for patients in the convalescent plasma and standard care arms, respectively (p = .46). The incremental cost was $4458 and the incremental quality-adjusted life day was -0.078. DISCUSSION: Convalescent plasma was less effective and more costly than standard care in treating hospitalized COVID-19.


Assuntos
COVID-19 , Adulto , Humanos , COVID-19/terapia , Qualidade de Vida , Bisoprolol , Análise Custo-Benefício , Soroterapia para COVID-19 , Canadá/epidemiologia
2.
Angew Chem Int Ed Engl ; 63(25): e202402511, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38634323

RESUMO

α-Olefins are valued and abundant building blocks from fossil resources. They are widely used to provide small-molecule or polymeric products. Despite numerous advantages of radical polymerization, it has been well-documented as textbook knowledge that α-olefins and their functionalized derivatives cannot be radically homopolymerized because of the degradative chain transfer side reactions. Herein, we report our studies on the homopolymerization of thiocyanate functionalized α-olefins enabled by 1,4-cyano group migration under radical conditions. By this approach, a library of ABC sequence-controlled polymers with high molecular weights can be prepared. We can also extend this strategy to the homopolymerization of α-substituted styrenic and acylate monomers which are known to be challenging to achieve. Overall, the demonstrated functional group migration radical polymerization could provide new possibilities to synthesize polymers with unprecedented main chain sequences and structures. These polymers are promising candidates for novel polymeric materials.

3.
Environ Sci Technol ; 57(22): 8269-8279, 2023 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-37227395

RESUMO

An incomplete understanding of how agrochemical nanocarrier properties affect their uptake and translocation in plants limits their application for promoting sustainable agriculture. Herein, we investigated how the nanocarrier aspect ratio and charge affect uptake and translocation in monocot wheat (Triticum aestivum) and dicot tomato (Solanum lycopersicum) after foliar application. Leaf uptake and distribution to plant organs were quantified for polymer nanocarriers with the same diameter (∼10 nm) but different aspect ratios (low (L), medium (M), and high (H), 10-300 nm long) and charges (-50 to +15 mV). In tomato, anionic nanocarrier translocation (20.7 ± 6.7 wt %) was higher than for cationic nanocarriers (13.3 ± 4.1 wt %). In wheat, only anionic nanocarriers were transported (8.7 ± 3.8 wt %). Both low and high aspect ratio polymers translocated in tomato, but the longest nanocarrier did not translocate in wheat, suggesting a phloem transport size cutoff. Differences in translocation correlated with leaf uptake and interactions with mesophyll cells. The positive charge decreases nanocarrier penetration through the leaf epidermis and promotes uptake into mesophyll cells, decreasing apoplastic transport and phloem loading. These results suggest design parameters to provide agrochemical nanocarriers with rapid and complete leaf uptake and an ability to target agrochemicals to specific plant organs, with the potential to lower agrochemical use and the associated environmental impacts.


Assuntos
Agroquímicos , Polímeros , Folhas de Planta , Transporte Biológico , Triticum
4.
Molecules ; 28(14)2023 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-37513384

RESUMO

The reaction of CF3COOAg, 3-bdppmapy (N,N-bis(diphenylphosphanylmethyl)-3-aminopyridine) and HTZ (1,2,4-triazole-3-thiol) in CH2Cl2/MeOH resulted in a dinuclear Ag/P/S complex [Ag2(TZ)2(3-bdppmapy)2]·xSol (1·xSol). Crystals of 1·xSol converted to 1·2MeOH in air at room temperature and further to 1 under vacuum upon heating. The solid-state, room-temperature photoluminescent emission of 1·xSol (510 nm) shifted to 494 nm (1·2MeOH) and 486 nm (1). Grinding solids of 1·2MeOH in air resulted in amorphous 1G characterized by solid-state emission at 468 nm, which converted to 1GR with 513 nm emission upon MeOH treatment. Grinding 1GR in air returned 1G, and this interconversion was reproducible over five cycles. The solid-state photoluminescence of 1G changed in response to vapors containing low-molecular weight alcohols but remained unchanged after exposure to other volatile organic compounds (VOCs) or to water vapor. Test papers impregnated with 1G could detect methanol in vapors from aqueous solutions at concentrations above 50%. Complex 1G is, therefore, an example of a stimuli-responsive molecular sensor for the detection of alcohols.

5.
Beilstein J Org Chem ; 19: 1580-1603, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37915554

RESUMO

Radical chemistry is one of the most important methods used in modern polymer science and industry. Over the past century, new knowledge on radical chemistry has both promoted and been generated from the emergence of polymer synthesis and modification techniques. In this review, we discuss radical chemistry in polymer science from four interconnected aspects. We begin with radical polymerization, the most employed technique for industrial production of polymeric materials, and other polymer synthesis involving a radical process. Post-polymerization modification, including polymer crosslinking and polymer surface modification, is the key process that introduces functionality and practicality to polymeric materials. Radical depolymerization, an efficient approach to destroy polymers, finds applications in two distinct fields, semiconductor industry and environmental protection. Polymer chemistry has largely diverged from organic chemistry with the fine division of modern science but polymer chemists constantly acquire new inspirations from organic chemists. Dialogues on radical chemistry between the two communities will deepen the understanding of the two fields and benefit the humanity.

6.
J Am Chem Soc ; 144(9): 3979-3988, 2022 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-35196003

RESUMO

Chemical systems may be maintained far from equilibrium by sequestering otherwise reactive species into different microenvironments. It remains a significant challenge to control the amount of chemical energy stored in such systems and to utilize it on demand to perform useful work. Here, we show that redox-active molecules compartmentalized in multiphasic structured-liquid devices can be charged and discharged to power a load on an external circuit. The two liquid phases of these devices feature charge-complementary polyelectrolytes that serve a dual purpose: they generate an ionically conductive coacervate membrane at the liquid-liquid interface, providing structural support; they also mitigate active-material crossover between phases via ion pairing with the oppositely charged anolyte and catholyte active materials. Structured-liquid batteries enabled by this design were rechargeable over hundreds of hours. We envision that these devices may be integrated with soft electronics to enable functional circuits for smart textiles, medical implants, and wearables.


Assuntos
Fontes de Energia Elétrica , Têxteis , Condutividade Elétrica , Eletrônica
7.
Molecules ; 27(19)2022 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-36234912

RESUMO

Core-shell nanocomposites comprising barium titanate, BaTiO3 (BTO), and poly(methyl methacrylate) (PMMA) chains grafted from its surface with varied grafting densities were prepared. BTO nanocrystals are high-k inorganic materials, and the obtained nanocomposites exhibit enhanced dielectric permittivity, as compared to neat PMMA, and a relatively low level of loss tangent in a wide range of frequencies. The impact of the molecular dynamics, structure, and interactions of the BTO surface on the polymer chains was investigated. The nanocomposites were characterized by broadband dielectric and vibrational spectroscopies (IR and Raman), transmission electron microscopy, differential scanning calorimetry, and nuclear magnetic resonance. The presence of ceramic nanoparticles in core-shell composites slowed down the segmental dynamic of PMMA chains, increased glass transition temperature, and concurrently increased the thermal stability of the organic part. It was also evidenced that, in addition to segmental dynamics, local ß relaxation was affected. The grafting density influenced the self-organization and interactions within the PMMA phase, affecting the organization on a smaller size scale of polymeric chains. This was explained by the interaction of the exposed surface of nanoparticles with polymer chains.


Assuntos
Nanopartículas , Polimetil Metacrilato , Bário , Simulação de Dinâmica Molecular , Nanopartículas/química , Polímeros/química , Polimetil Metacrilato/química
8.
Environ Sci Technol ; 55(18): 12549-12560, 2021 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-34464106

RESUMO

Demand for rare earth elements (REEs) is increasing, and REE production from ores is energy-intensive. Recovering REEs from waste streams can provide a more sustainable approach to help meet REE demand but requires materials with high selectivity and capacity for REEs due to the low concentration of REEs and high competing ion concentrations. Here, we developed a phosphate polymer nanogel (PPN) to selectively recover REEs from low REE content waste streams, including leached fly ash. A high phosphorus content (16.2 wt % P as phosphate groups) in the PPN provides an abundance of coordination sites for REE binding. In model solutions, the distribution coefficient (Kd) for all REEs ranged from 1.3 × 105 to 3.1 × 105 mL g-1 at pH = 7, and the sorption capacity (qm) for Nd, Gd, and Ho were ∼300 mg g-1. The PPN was selective toward REEs, outcompeting cations (Ca, Mg, Fe, Al) at up to 1000-fold excess concentration. The PPN had a Kd of ∼105-106 mL g-1 for lanthanides in coal fly ash leachate (pH = 5), orders of magnitude higher than the Kd of major competing ions (∼103-104 mL g-1). REEs were recovered from the PPN using 3.5% HNO3, and the material remained effective over three sorption-elution cycles. The high REE capacity and selectivity and good durability in a real waste stream matrix suggest its potential to recover REEs from a broad range of secondary REE stocks.


Assuntos
Elementos da Série dos Lantanídeos , Metais Terras Raras , Nanogéis , Fosfatos , Polímeros
9.
Environ Sci Technol ; 55(15): 10758-10768, 2021 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-34283571

RESUMO

Determination of how the properties of nanocarriers of agrochemicals affect their uptake and translocation in plants would enable more efficient agent delivery. Here, we synthesized star polymer nanocarriers poly(acrylic acid)-block-poly(2-(methylsulfinyl)ethyl acrylate) (PAA-b-PMSEA) and poly(acrylic acid)-block-poly((2-(methylsulfinyl)ethyl acrylate)-co-(2-(methylthio)ethyl acrylate)) (PAA-b-P(MSEA-co-MTEA)) with well-controlled sizes (from 6 to 35 nm), negative charge content (from 17% to 83% PAA), and hydrophobicity and quantified their leaf uptake, phloem loading, and distribution in tomato (Solanum lycopersicum) plants 3 days after foliar application of 20 µL of a 1g L-1 star polymer solution. In spite of their property differences, ∼30% of the applied star polymers translocated to other plant organs, higher than uptake of conventional foliar applied agrochemicals (<5%). The property differences affected their distribution in the plant. The ∼6 nm star polymers exhibited 3 times higher transport to younger leaves than larger ones, while the ∼35 nm star polymer had over 2 times higher transport to roots than smaller ones, suggesting small star polymers favor symplastic unloading in young leaves, while larger polymers favor apoplastic unloading in roots. For the same sized star polymer, a smaller negative charge content (yielding ζ ∼ -12 mV) enhanced translocation to young leaves and roots, whereas a larger negative charge (ζ < -26 mV) had lower mobility. Hydrophobicity only affected leaf uptake pathways, but not translocation. This study can help design agrochemical nanocarriers for efficient foliar uptake and targeting to desired plant organs, which may decrease agrochemical use and environmental impacts of agriculture.


Assuntos
Folhas de Planta , Polímeros , Transporte Biológico , Interações Hidrofóbicas e Hidrofílicas , Raízes de Plantas
10.
Environ Sci Technol ; 55(2): 1231-1241, 2021 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-33404237

RESUMO

Technologies for removal of mercury from produced water and hydrocarbon phases are desired by oil and gas production facilities, oil refineries, and petrochemical plants. Herein, we synthesize and demonstrate the efficacy of an amphiphilic, thiol-abundant (11.8 wt % S, as thiol) polymer nanogel that can remove environmentally relevant mercury species from both produced water and the liquid hydrocarbon. The nanogel disperses in both aqueous and hydrocarbon phases. It has a high sorption affinity for dissolved Hg(II) complexes and Hg-dissolved organic matter complexes found in produced water and elemental (Hg0) and soluble Hg-alkyl thiol species found in hydrocarbons. X-ray absorption spectroscopy analysis indicates that the sorbed mercury is transformed to a surface-bound Hg(SR)2 species in both water and hydrocarbon regardless of its initial speciation. The nanogel had high affinity to native mercury species present in real produced water (>99.5% removal) and in natural gas condensate (>85% removal) samples, removing majority of the mercury species using only a 50 mg L-1 applied dose. This thiolated amphiphilic polymeric nanogel has significant potential to remove environmentally relevant mercury species from both water and hydrocarbon at low applied doses, outperforming reported sorbents like sulfur-impregnated activated carbons because of the mass of accessible thiol groups in the nanogel.


Assuntos
Mercúrio , Hidrocarbonetos , Nanogéis , Polímeros , Compostos de Sulfidrila , Água
11.
BMC Plant Biol ; 19(1): 235, 2019 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-31159732

RESUMO

BACKGROUND: Elymus L. is the largest genus in the tribe Triticeae Dumort., encompassing approximately 150 polyploid perennial species widely distributed in the temperate regions of the world. It is considered to be an important gene pool for improving cereal crops. However, a shortage of molecular marker limits the efficiency and accuracy of genetic breeding for Elymus species. High-throughput transcriptome sequencing data is essential for gene discovery and molecular marker development. RESULTS: We obtained the transcriptome dataset of E. sibiricus, the type species of the genus Elymus, and identified a total of 8871 putative EST-SSRs from 6685 unigenes. Trinucleotides were the dominant repeat motif (4760, 53.66%), followed by dinucleotides (1993, 22.47%) and mononucleotides (1876, 21.15%). The most dominant trinucleotide repeat motif was CCG/CGG (1119, 23.5%). Sequencing of PCR products showed that the sequenced alleles from different Elymus species were homologous to the original SSR locus from which the primer was designed. Different types of tri-repeats as abundant SSR motifs were observed in repeat regions. Two hundred EST-SSR primer pairs were designed and selected to amplify ten DNA samples of Elymus species. Eighty-seven pairs of primer (43.5%) generated clear and reproducible bands with expected size, and showed good transferability across different Elymus species. Finally, thirty primer pairs successfully amplified ninety-five accessions of seventeen Elymus species, and detected significant amounts of polymorphism. In general, hexaploid Elymus species with genomes StStHHYY had a relatively higher level of genetic diversity (H = 0.219, I = 0.330, %P = 63.7), while tetraploid Elymus species with genomes StStYY had low level of genetic diversity (H = 0.182, I = 0.272, %P = 50.4) in the study. The cluster analysis showed that all ninety-five accessions were clustered into three major clusters. The accessions were grouped mainly according to their genomic components and origins. CONCLUSIONS: This study demonstrated that transcriptome sequencing is a fast and cost-effective approach to molecular marker development. These EST-SSR markers developed in this study are valuable tools for genetic diversity, evolutionary, and molecular breeding in E. sibiricus, and other Elymus species.


Assuntos
Elymus/classificação , Elymus/genética , Etiquetas de Sequências Expressas , Variação Genética , Repetições de Microssatélites , Marcadores Genéticos , Sequenciamento de Nucleotídeos em Larga Escala , Filogenia , Proteínas de Plantas/análise , RNA de Plantas/análise , Alinhamento de Sequência , Análise de Sequência de RNA
12.
J Am Chem Soc ; 139(37): 12931-12934, 2017 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-28885020

RESUMO

An aqueous-based approach for the scalable synthesis of nitrogen-doped porous carbons with high specific surface area (SSA) and high nitrogen content is presented. Low molecular weight polyacrylonitrile (PAN) is solubilized in water in the presence of ZnCl2 that also acts as a volatile porogen during PAN pyrolysis to form mesoporous structures with significantly increased SSA. By templating with commercial SiO2 nanoparticles, nanocellulose fillers or filter paper, nanocarbons with SSA = 1776, 1366, and 1501 m2/g, respectively and 10 wt % N content were prepared. The materials formed by this benign process showed excellent catalytic activity in oxygen reduction reaction via the four-electron mechanism.

13.
Langmuir ; 33(43): 12276-12284, 2017 10 31.
Artigo em Inglês | MEDLINE | ID: mdl-29017325

RESUMO

Severe water pollution issues present an important contemporary challenge that drives the development and advancement of efficient and environmentally benign photocatalysts that enable the degradation of pollutants upon visible light irradiation. One example is zinc oxide/carbon (ZnO/C) hybrid materials that have been shown to be effective photocatalysts. To maximize the effectiveness of ZnO/C hybrids, materials with high accessible surface area of ZnO are required. Here, a novel strategy is presented to enable the synthesis of fine dispersions of ZnO nanoparticles within a porous carbon matrix. The synthesis entails the grafting of ZnO nanparticles with polystyrene-b-poly(styrene-co-acrylonitrile) (PS-b-PSAN) block copolymer and subsequent pyrolysis of the material under inert gas (N2) atmosphere. During the pyrolysis process, the PS block effectively prevents agglomeration of ZnO particles, thus resulting in a fine dispersion of ZnO nanocrystals within a prorous C matrix. Materials are found to exhibit a dye adsorption capacity of 125 mg g-1 (from a methylene blue aqueous solution with a concentration of 305 mg L-1) and dye degradation rate constant of 0.021 min-1. The significant increase of effective surface area and degradation efficacy (as compared to ZnO/C synthesized by the pyrolysis of binary PSAN/ZnO blends) is rationalized as a consequence of the increased porosity that promotes dye adsorption and transport within the hybrid material.

14.
Angew Chem Int Ed Engl ; 56(10): 2740-2743, 2017 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-28164438

RESUMO

A DNA synthesizer was successfully employed for preparation of well-defined polymers by atom transfer radical polymerization (ATRP), in a technique termed AutoATRP. This method provides well-defined homopolymers, diblock copolymers, and biohybrids under automated photomediated ATRP conditions. PhotoATRP was selected over other ATRP methods because of mild reaction conditions, ambient temperature, tolerance to oxygen, and no need to introduce reducing agents or radical initiators. Both acrylate and methacrylate monomers were successfully polymerized with excellent control in the DNA synthesizer. Diblock copolymers were synthesized with different targeted degrees of polymerization and with high retention of chain-end functionality. Both hydrophobic and hydrophilic monomers were grafted from DNA. The DNA-polymer hybrids were characterized by SEC and DLS. The AutoATRP method provides an efficient route to prepare a range of different polymeric materials, especially polymer-biohybrids.


Assuntos
Automação/instrumentação , DNA/síntese química , Polímeros/síntese química , DNA/química , Radicais Livres/síntese química , Radicais Livres/química , Interações Hidrofóbicas e Hidrofílicas , Estrutura Molecular , Polimerização , Polímeros/química
15.
Langmuir ; 32(49): 13207-13213, 2016 12 13.
Artigo em Inglês | MEDLINE | ID: mdl-27951696

RESUMO

Poly(styrene-co-acrylonitrile) (PSAN)-capped ZnO nanoparticles (NPs) were synthesized by a "ligand exchange" method. First, octylamine (OA)-capped ZnO NPs were prepared by reaction of OA and zinc 2-ethylhexanoate (Zn(EH)2). Then PSAN polymer ligands were synthesized by activators regenerated by electron transfer (ARGET) atom transfer radical polymerization (ATRP) and were efficiently exchanged with OA ligands on the ZnO particle surface benefiting from the relatively low boiling point of OA (175 °C). The morphology, content of ZnO, and grafting density of the nanocomposite were well controlled by altering the ratio between OA and polymer ligands as well as the molecular weight of PSAN-NH2 used in the exchange reaction. The resulting ZnO/polymer nanocomposites were stable in THF with narrow size distributions and varying grafting densities from 0.9 to 2.5 nm-2. With excess amount of polymer ligands, individual dispersed ZnO NPs were observed. However, with a limited amount of ligands, NPs clusters were formed, as confirmed by TEM and DLS.

16.
Faraday Discuss ; 186: 17-30, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26764893

RESUMO

Recent progress in the area of surface-initiated controlled radical polymerization (SI-CRP) has enabled the synthesis of polymer-grafted colloids with precise control over the architecture of grafted chains. The resulting 'particle brush materials' are of interest both from a fundamental as well as applied perspective because structural frustrations (associated with the tethering of chains to a curved surface) imply a sensitive dependence of the interactions between brush particles on the architecture of surface-tethered chains that offers new opportunities to design hybrid materials with novel functionalities. An important prerequisite for establishing structure-property relations in particle brush materials is to understand the role of homopolymer impurities that form, for example, by thermal self-initiation. This contribution presents a detailed discussion of the role of homopolymer additives on the structure and mechanical properties of particle brush materials. The results suggest that the dissolution of homopolymer fillers follows a two-step mechanism comprised of the initial segregation of homopolymer to the interstitial regions within the array and the subsequent swelling of the particle brush (depending on the respective degree of polymerization of brush and linear chains). Addition of even small amounts of homopolymer is found to significantly increase the fracture toughness of particle brush assembly structures. The increased resistance to failure could enable the synthesis of robust colloidal crystal type materials that can be processed into complex shapes using 'classical' polymer forming techniques such as molding or extrusion.

17.
Soft Matter ; 12(15): 3527-37, 2016 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-26979521

RESUMO

The effect of polymer modification on the deformation characteristics and processibility of particle assembly structures is analyzed as a function of particle size and degree of polymerization of surface-tethered chains. A pronounced increase of the fracture toughness (by approximately one order of magnitude) is observed as the degree of polymerization exceeds a threshold value that increases with particle size. The threshold value is interpreted as being related to the transition of tethered chains from stretched-to-relaxed conformation (and the associated entanglement of tethered chains) and agrees with predictions from scaling theory. The increase in toughness is reduced with increasing particle size - this effect is rationalized as a consequence of the decrease of entanglement density with increasing dimension of interstitial (void) space in particle array structures. The increased fracture toughness of particle brush materials (with sufficient degree of polymerization of tethered chains) enables the fabrication of ordered colloidal films and even complex 3D shapes by scalable polymer processing techniques, such as spin coating and micromolding. The results, therefore, suggest new opportunities for the processing of colloidal material systems that could find application in the economical fabrication of functional components or systems compromised of colloidal materials.

18.
Zhonghua Nan Ke Xue ; 22(1): 42-5, 2016 Jan.
Artigo em Zh | MEDLINE | ID: mdl-26931025

RESUMO

OBJECTIVE: To investigate the clinical application of the ureteral dilation catheter combined with the balloon catheter under the ureteroscope in the treatment of urethral stricture in men. METHODS: Under the ureteroscope, 45 male patients with urethral stricture received placement of a zebra guide wire through the strictured urethra into the bladder and then a ureteral dilation catheter along the guide wire, followed by dilation of the urethra from F8 initially to F14 and F16. Again, the ureteroscope was used to determine the length of the strictured urethra, its distance to the external urethral orifice, and whether it was normally located. An F24 balloon catheter and then a metal urethral calibrator was used for the dilation of the strictured urethra. After removal of the F18-F22 urethral catheter at 8 weeks, the urinary flow rate was measured immediately and again at 3 months. RESULTS: All the operations were successfully performed without serious complications. The maximum urinary flow rate was (13.3-29.9) ml/s (mean [17.7 ± 3.2] ml/s) at the removal of the catheter and (15.2-30.8) ml/s (mean [19.8 ± 3.9] ml/s) at 3 months after it. Smooth urination was found in all the patients during the 6-24 months follow-up. CONCLUSION: The application of the ureteral dilation catheter combined with, the balloon catheter under the ureteroscope is a good option for the treatment of male urethral stricture for its advantages of uncomplicatedness, safety, effectiveness, few complications, less pain, high success rate, and repeatable operation.


Assuntos
Cateterismo , Ureteroscópios , Estreitamento Uretral/terapia , Cateteres Urinários , Humanos , Masculino , Uretra , Bexiga Urinária , Micção
19.
J Urol ; 193(6): 2116-22, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25619454

RESUMO

PURPOSE: Uroseptic shock is a life threatening complication after upper urinary tract endoscopic lithotripsy. Prompt diagnosis and treatment are paramount for patient survival. We identified a practical predictor of upper urinary tract endoscopic lithotripsy induced uroseptic shock in an animal model. We validated the results by retrospectively reviewing multicenter clinical records. MATERIALS AND METHODS: We ligated the rabbit ureter and injected Escherichia coli solution in the renal pelvis to create a uroseptic shock model. White blood count and other parameters were measured at different intervals and bacterial concentrations. Results were compared with clinical findings in 48 patients who experienced uroseptic shock after upper urinary tract endoscopic lithotripsy at a total of 8 medical centers. We used a ROC curve to evaluate the predictive value of parameters for uroseptic shock. RESULTS: We established a stable rabbit model by injecting 9.0 × 10(8) cfu/ml E. coli in the renal pelvis at a dose of 2 ml/kg. In patients and rabbits with uroseptic shock the white blood count decreased in the first 2 hours after the procedure. The ROC curve showed that the white blood count threshold within the first 2 hours of uroseptic shock was 2.85 × 10(9)/L. Sensitivity and specificity for predicting uroseptic shock were 95.9% and 92.7%, respectively. CONCLUSIONS: The white blood count decreased drastically within the first 2 hours during the development of uroseptic shock. This could be an ideal predictor of uroseptic shock after upper urinary tract endoscopic lithotripsy. In patients with high risk factors for uroseptic shock the white blood count should be measured within 2 hours after upper urinary tract endoscopic lithotripsy.


Assuntos
Endoscopia , Leucócitos , Litotripsia/efeitos adversos , Litotripsia/métodos , Choque Séptico/sangue , Choque Séptico/etiologia , Infecções Urinárias/sangue , Infecções Urinárias/etiologia , Animais , Contagem de Leucócitos , Masculino , Valor Preditivo dos Testes , Coelhos , Fatores de Tempo , Pesquisa Translacional Biomédica
20.
Zhonghua Nan Ke Xue ; 21(6): 541-4, 2015 Jun.
Artigo em Zh | MEDLINE | ID: mdl-26242046

RESUMO

OBJECTIVE: To improve the methods and reduce the complications of circumcision with a disposable suture device. METHODS: This study included 325 male patients aged 14-65 (mean 28.9) years, treated for redundant prepuce or phimosis by modified (n = 201) or conventional circumcision with a disposable suture device (n = 124). We compared the incidence of complications and the patients' satisfaction between the two surgical methods. RESULTS: Compared with conventional circumcision, the modified method showed a significantly lower incidence of postoperative bleeding (14.52% vs 2.49% , P < 0.05) and a lower rate of second surgery for penile hematoma (4.03% vs 0.50%, P < 0.05). The patients' satisfaction was markedly higher with the modified method (91.94%) than with conventional circumcision (97.51%) (P < 0.05). CONCLUSION: Modified circumcision with the disposable suture device can significantly reduce the incidence of postoperative bleeding and penile hematoma and therefore deserves wide clinical application.


Assuntos
Circuncisão Masculina/instrumentação , Equipamentos Descartáveis , Técnicas de Sutura/instrumentação , Adolescente , Adulto , Idoso , Circuncisão Masculina/efeitos adversos , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Satisfação do Paciente , Pênis/cirurgia , Fimose/cirurgia , Complicações Pós-Operatórias/epidemiologia , Suturas
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