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1.
Proc Natl Acad Sci U S A ; 120(46): e2301994120, 2023 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-37903247

RESUMO

The explosive eruption of the Hunga Tonga-Hunga Ha'apai (HTHH) volcano on 15 January 2022 injected more water vapor into the stratosphere and to higher altitudes than ever observed in the satellite era. Here, the evolution of the stratospherically injected water vapor is examined as a function of latitude, altitude, and time in the year following the eruption (February to December 2022), and perturbations to stratospheric chemical composition resulting from the increased sulfate aerosols and water vapor are identified and analyzed. The average calculated mass distribution of elevated water vapor between hemispheres is approximately 78% Southern Hemisphere (SH) and 22% Northern Hemisphere in 2022. Significant changes in stratospheric composition following the HTHH eruption are identified using observations from the Aura Microwave Limb Sounder satellite instrument. The dominant features in the monthly mean vertical profiles averaged over 15° latitude ranges are decreases in O3 (-14%) and HCl (-22%) at SH midlatitudes and increases in ClO (>100%) and HNO3 (43%) in the tropics, with peak pressure-level perturbations listed. Anomalies in column ozone from 1.2-100 hPa due to the HTHH eruption include widespread O3 reductions in SH midlatitudes and O3 increases in the tropics, with peak anomalies in 15° latitude-binned, monthly averages of approximately -7% and +5%, respectively, occurring in austral spring. Using a 3-dimensional chemistry-climate-aerosol model and observational tracer correlations, changes in stratospheric composition are found to be due to both dynamical and chemical factors.

2.
Proc Natl Acad Sci U S A ; 120(30): e2302014120, 2023 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-37459548

RESUMO

Spontaneous generation of reactive oxygen species (ROS) in aqueous microdroplets or at a water vapor-silicate interface is a new source of redox chemistry. However, such generation occurs with difficulty in liquid water having a large ionic strength. We report that ROS is spontaneously produced when water vapor contacts hydrogen-bonded hydroxyl groups on a silicate surface. The evolution of hydrogen-bonded species such as hydroxyl groups was investigated by using two-dimensional, time-resolved FT-IR spectroscopy. The participation of water vapor in ROS generation is confirmed by investigating the reaction of D2O vapor and hydroxyl groups on a silicate surface. We propose a reaction pathway for ROS generation based on the change of the hydrogen-bonding network and corresponding electron transfer onto the silicate surface in the water vapor-solid contact process. Our observations suggest that ROS production from water vapor-silicate contact electrification could have contributed to oxidation during the Archean Eon before the Great Oxidation Event.

3.
Emerg Infect Dis ; 30(3): 548-554, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38407146

RESUMO

Because epidemiologic and environmental risk factors for nontuberculous mycobacteria (NTM) have been reported only infrequently, little information exists about those factors. The state of Virginia, USA, requires certain ecologic features to be included in reports to the Virginia Department of Health, presenting a unique opportunity to study those variables. We analyzed laboratory reports of Mycobacterium avium complex (MAC) and M. abscessus infections in Virginia during 2021-2023. MAC/M. abscessus was isolated from 6.19/100,000 persons, and 2.37/100,000 persons had MAC/M. abscessus lung disease. M. abscessus accounted for 17.4% and MAC for 82.6% of cases. Saturated vapor pressure was associated with MAC/M. abscessus prevalence (prevalence ratio 1.414, 95% CI 1.011-1.980; p = 0.043). Self-supplied water use was a protective factor (incidence rate ratio 0.304, 95% CI 0.098-0.950; p = 0.041). Our findings suggest that a better understanding of geographic clustering and environmental water exposures could help develop future targeted prevention and control efforts.


Assuntos
Carbamatos , Mycobacterium abscessus , Micobactérias não Tuberculosas , Pirazinas , Piridinas , Virginia/epidemiologia , Complexo Mycobacterium avium , Água
4.
Small ; 20(32): e2401009, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38552229

RESUMO

Unavoidable water formation during the reduction of solid catalyst precursors has long been known to influence the nanoparticle size and dispersion in the active catalyst. This in situ transmission electron microscopy study provides insight into the influence of water vapor at the nanoscale on the nucleation and growth of the nanoparticles (2-16 nm) during the reduction of a nickel phyllosilicate catalyst precursor under H2/Ar gas at 700 °C. Water suppresses and delays nucleation, but counterintuitively increases the rate of particle growth. After full reduction is achieved, water vapor significantly enhances Ostwald ripening which in turn increases the likelihood of particle coalescence. This study proposes that water leads to formation of mobile nickel hydroxide species, leading to faster rates of particle growth during and after reduction.

5.
J Urol ; 211(1): 11-19, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37706750

RESUMO

PURPOSE: The purpose of this American Urological Association (AUA) Guideline amendment is to provide a useful reference on the effective evidence-based management of male lower urinary tract symptoms secondary/attributed to BPH (LUTS/BPH). MATERIALS AND METHODS: The Minnesota Evidence Review Team searched Ovid MEDLINE, the Cochrane Library, and the Agency for Healthcare Research and Quality (AHRQ) database to identify studies relevant to the management of BPH. The guideline was updated in 2023 to capture eligible literature published between September 2020 and October 2022. When sufficient evidence existed, the body of evidence was assigned a strength rating of A (high), B (moderate), or C (low) for support of Strong, Moderate, or Conditional Recommendations. In the absence of sufficient evidence, additional information is provided as Clinical Principles and Expert Opinions. RESULTS: The BPH amendment resulted in changes to statements/supporting text on combination therapy, photoselective vaporization of the prostate (PVP), water vapor thermal therapy (WVTT), laser enucleation, and prostate artery embolization (PAE). A new statement on temporary implanted prostatic devices (TIPD) was added. In addition, statements on transurethral needle ablation (TUNA) and transurethral microwave thermotherapy (TUMT) were removed and information regarding these legacy technologies was added to the background section. References and the accompanying treatment algorithms were updated to align with the updated text. CONCLUSION: This guideline seeks to improve clinicians' ability to evaluate and treat patients with BPH/LUTS based on currently available evidence. Future studies will be essential to further support these statements to improve patient care.


Assuntos
Terapia a Laser , Sintomas do Trato Urinário Inferior , Hiperplasia Prostática , Ressecção Transuretral da Próstata , Humanos , Masculino , Sintomas do Trato Urinário Inferior/terapia , Sintomas do Trato Urinário Inferior/complicações , Próstata/cirurgia , Hiperplasia Prostática/terapia , Hiperplasia Prostática/cirurgia , Ressecção Transuretral da Próstata/métodos , Resultado do Tratamento , Guias de Prática Clínica como Assunto
6.
Mol Pharm ; 21(2): 704-717, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38194618

RESUMO

Monoclonal antibodies (mAbs) are active components of therapeutic formulations that interact with the water-vapor interface during manufacturing, storage, and administration. Surface adsorption has been demonstrated to mediate antibody aggregation, which leads to a loss of therapeutic efficacy. Controlling mAb adsorption at interfaces requires a deep understanding of the microscopic processes that lead to adsorption and identification of the protein regions that drive mAb surface activity. Here, we report all-atom molecular dynamics (MD) simulations of the adsorption behavior of a full IgG1-type antibody at the water/vapor interface. We demonstrate that small local changes in the protein structure play a crucial role in promoting adsorption. Also, interfacial adsorption triggers structural changes in the antibody, potentially contributing to the further enhancement of surface activity. Moreover, we identify key amino acid sequences that determine the adsorption of antibodies at the water-air interface and outline strategies to control the surface activity of these important therapeutic proteins.


Assuntos
Anticorpos Monoclonais , Vapor , Anticorpos Monoclonais/química , Adsorção , Água/química , Composição de Medicamentos
7.
World J Urol ; 42(1): 60, 2024 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-38280069

RESUMO

PURPOSE: In recent years, water vapor thermal therapy (WVTT) has spread as minimally invasive technique in lower urinary tract symptoms due to benign prostatic hyperplasia treatment. Even if its safety and feasibility have been largely proved in young men, nobody has proved the same feasibility and safety in the elderly (men older than 75 years old). Our aim is to compare WVTT safety outcomes in men older than 75 with younger men. METHODS: We prospectively collected data on men who underwent water vapor thermal therapy from 2019. We compared data on operative time, number of injections, intra-operative and post-operative complications, reinterventions rate. RESULTS: We enrolled 426 patients; among these, 60 were older than 75 years old, 366 were younger. Our cohorts of patients had similar results in terms of intra-operative and post-operative complications. Operative time accounts about 11 min for both groups (p = 0.535), total number of injections was seven for young men and eight for elderly (p = 0.314). We found no intra-operative complications in elderly men group and only one in the younger group (p = 0.678), while five younger men underwent clot retention, and two elderly men experienced this complication (p = 0.239). Only one transfusion occurred in the elderly group. No differences between groups occurred in terms of length of stay, post-operative urinary retention and reintervention rate, while catheterization time was longer in the elderly men. CONCLUSION: WVTT is a safe procedure in elderly patients with comparable intra-operative and post-operative complication rate in comparison with younger patients.


Assuntos
Hipertermia Induzida , Sintomas do Trato Urinário Inferior , Hiperplasia Prostática , Masculino , Idoso , Humanos , Vapor , Idoso Fragilizado , Hiperplasia Prostática/complicações , Hipertermia Induzida/métodos , Itália , Sintomas do Trato Urinário Inferior/etiologia , Resultado do Tratamento
8.
World J Urol ; 42(1): 383, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38904777

RESUMO

PURPOSE: To investigate safety and feasibility of performing water vapor thermal therapy (WVTT; Rezum, Boston Scientific, Marlborough, MA, USA) without postoperative catheterization among men with benign prostatic hyperplasia. METHODS: This is a prospective, single arm, unblinded pilot study of 20 consecutive male patients ages 40-80 who underwent WVTT at a single academic institution. All patients underwent 1 injection per lobe at the point of maximal obstruction based on visualization. Primary outcome was evaluation of voiding parameters, symptom scores, and need for catheterization at 3 day, 1, 3, and 6 month follow up compared to baseline visit 30 days prior to surgery. RESULTS: Mean age was 65 years (range 55-75). Mean prostate volume and PVR were 43 cc (range 30-68) and 89 cc, with 30% (n = 6) having median lobes. Patients received 2-3 treatments based on presence of bilobar versus trilobar hyperplasia. One patient (55 cc prostate, no median lobe) required catheterization for acute urinary retention on postoperative day 2. No patients required antibiotics for urinary tract infection or inpatient readmission within 30 days. Qmax significantly increased from 6 mL/s to 8, 13, 12, and 14 at 3 days, 1, 3, and 6 months (p < 0.05). IPSS decreased from 17 preoperatively to 10, 6, 7, and 8 (p < 0.05). No significant differences were noted in PVR, IIEF, MSHQ-EjD, or SF-12. CONCLUSIONS: In well-selected men, catheter-free WVTT is feasible and improved voiding parameters and symptom scores. No changes in sexual function, infectious complications, or readmission were noted. Only 1 patient (5%) required postoperative catheterization within 30 days.


Assuntos
Estudos de Viabilidade , Hiperplasia Prostática , Vapor , Humanos , Masculino , Hiperplasia Prostática/terapia , Pessoa de Meia-Idade , Idoso , Estudos Prospectivos , Projetos Piloto , Resultado do Tratamento , Idoso de 80 Anos ou mais , Adulto , Hipertermia Induzida/métodos
9.
Environ Sci Technol ; 58(27): 12147-12154, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38934559

RESUMO

Increasing worldwide contamination with organic chemical compounds is a paramount environmental challenge facing humanity. Once they enter nature, pollutants undergo transformative processes that critically shape their environmental impacts and associated risks. This research unveils previously overlooked yet widespread pathways for the transformations of organic pollutants triggered by water vapor condensation, leading to spontaneous oxidation and hydrolysis of organic pollutants. These transformations exhibit variability through either sequential or parallel hydrolysis and oxidation, contingent upon the functional groups within the organic pollutants. For instance, acetylsalicylic acid on the goethite surface underwent sequential hydrolysis and oxidation that first hydrolyzed to salicylic acid followed by hydroxylation oxidation of the benzene moiety driven by the hydroxyl radical (•OH). In contrast, chloramphenicol underwent parallel oxidation and hydrolysis, forming hydroxylated chloramphenicol and 2-amino-1-(4-nitrophenyl)-1,3-propanediol, respectively. The spontaneous oxidation and hydrolysis occurred consistently on three naturally abundant iron minerals with the key factors being •OH production capacity and surface binding strength. Given the widespread presence of iron minerals on Earth's surface, these spontaneous transformation paths could play a role in the fate and risks of organic pollutants of health concerns.


Assuntos
Ferro , Oxirredução , Hidrólise , Ferro/química , Minerais/química , Vapor , Compostos Orgânicos/química , Radical Hidroxila/química
10.
Environ Sci Technol ; 58(8): 3985-3996, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38357760

RESUMO

Achieving no or low polychlorinated byproduct selectivity is essential for the chlorinated volatile organic compounds (CVOCs) degradation, and the positive roles of water vapor may contribute to this goal. Herein, the oxidation behaviors of chlorobenzene over typical Mn-based catalysts (MnO2 and acid-modified MnO2) under dry and humid conditions were fully explored. The results showed that the presence of water vapor significantly facilitates the deep mineralization of chlorobenzene and restrains the formation of Cl2 and dichlorobenzene. This remarkable water vapor-promoting effect was conferred by the MnO2 substrate, which could suitably synergize with the postconstructed acidic sites, leading to good activity, stability, and desirable product distribution of acid-modified MnO2 catalysts under humid conditions. A series of experiments including isotope-traced (D2O and H218O) CB-TPO provided complete insights into the direct involvement of water molecules in chlorobenzene oxidation reaction and attributed the root cause of the water vapor-promoting effect to the proton-rich environment and highly reactive water-source oxygen species rather than to the commonly assumed cleaning effect or hydrogen proton transfer processes (generation of active OOH). This work demonstrates the application potential of Mn-based catalysts in CVOCs elimination under practical application conditions (containing water vapor) and provides the guidance for the development of superior industrial catalysts.


Assuntos
Óxidos , Vapor , Catálise , Clorobenzenos/química , Compostos de Manganês , Óxidos/química , Prótons
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