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1.
Environ Sci Technol ; 58(18): 7849-7859, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38670542

RESUMO

Abiotic resources are indispensable in society, but there are concerns regarding their depletion, scarcity, and increasing prices, resulting in potential economic damage in the future. To address these concerns, it is effective to consider the external costs of resource use. Although resource availability is different among mining sites, and local conditions are relevant in assessing resource scarcity, previous studies have assessed external costs and potential impacts of abiotic resource use globally. This study provides country-specific characterization factors (CFs) of abiotic resource use in life cycle impact assessment based on the user cost model, which represents the external costs of abiotic resource use to reflect country-specific resource scarcity. We demonstrate considerable variations in the CFs depending on the mining country, suggesting that the choice of mining country can affect external costs. The global external cost of abiotic resource use in 2020 was estimated at 1.9 trillion $, with a major contribution from the extraction of fossil fuels in the United States. Historical trends of the CFs and relevant parameters showed temporal fluctuations, emphasizing the importance of regularly updating the data underlying the calculation of the CFs. Country-level assessments of the external costs of resource use can contribute to discussions on the responsibilities of consuming countries by incorporating material footprint studies.


Assuntos
Mineração , Mineração/economia
2.
Anal Chem ; 95(28): 10744-10751, 2023 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-37418336

RESUMO

An electrospray operated in the steady cone-jet mode is highly stable but the operating state can shift to pulsation or multijet modes owing to changes in flow rate, surface tension, and electrostatic variables. Here, a simple feedback control system was developed using the spray current and the apex angle of a Taylor cone to determine the error signal for correcting the emitter voltage. The system was applied to lock the cone-jet mode operation against external perturbations. For a pump-driven electrospray at a regulated flow rate, the apex angle of the Taylor cone decreased with increasing voltage. In contrast, for a voltage-driven electrospray with low flow resistance, the angle was found to increase with the emitter voltage. A simple algorithm based on iterative learning control was formulated and implemented using a personal computer to automatically correct the emitter voltage in response to the error signal. For voltage-driven electrospray ionization (ESI), the feedback control of the spray current can also be used to regulate the flow rate to an arbitrary value or pattern. Electrospray ionization-mass spectrometry (ESI-MS) with feedback control was demonstrated to produce ion signal acquisition with long-term stability that was insusceptible to the emulated external disturbances.

3.
Anal Bioanal Chem ; 412(18): 4327-4341, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32367293

RESUMO

Acetylcholine (ACh) is a crucial neurotransmitter that is involved in airway constriction. In fact, excessive ACh binding to M3 muscarinic receptor leads to airflow obstruction via smooth muscle contraction. Previous studies have suggested cholinergic malfunction in the pathogenesis of asthma; however, the distribution and abundance of ACh in asthmatic lungs remain unclear because of the challenges of imaging ACh in lung tissue. In this study, we successfully detected and visualised ACh in mouse lung tissue by using Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR-MS). Here, we applied the ACh imaging method to the two groups of house dust mite-sensitised asthma model mice harbouring different inflammatory levels. The imaging results showed that the lungs of mice had a relatively uniform ACh distribution with some areas of heterogeneity. The lungs of asthma model mice had significantly more ACh than control mice, and the ACh increase was potentiated with intense eosinophil infiltration without acetylcholinesterase deficits. These results indicate that ACh hypersecretion is mediated by an increased infiltration of eosinophils in asthma aggravation. This study provides the first evidence that secreted ACh is elevated with asthma severity in the lungs of asthma model animals by a direct ACh imaging technique with FT-ICR-MS.


Assuntos
Acetilcolina/análise , Asma/patologia , Pulmão/patologia , Espectrometria de Massas/métodos , Animais , Modelos Animais de Doenças , Feminino , Análise de Fourier , Pulmão/química , Camundongos Endogâmicos BALB C
4.
No Shinkei Geka ; 47(4): 449-454, 2019 Apr.
Artigo em Japonês | MEDLINE | ID: mdl-31061230

RESUMO

A female neonate presented with a cranial mass in the left parietal lobe region. She was born through Cesarean section, and there was no history of birth trauma or head injury. Her mother noticed the mass two weeks after birth. It increased slowly in size and turned stiff. CT showed a skull tumor with calcification. MRI findings, with no vascular abnormalities, indicated a possibility of cephalohematoma. 67Ga scintigraphy showed no abnormal uptake in the cranial mass or any other systemic lesion. We performed an operation to examine the histology and to adjust the shape of the skull. The diagnosis from the histological examination was cephalohematoma with calcification. Cephalohematoma occurs less commonly in the case of Cesarean section and usually resolves spontaneously without any intervention. Some studies have reported birth trauma even though the baby was born through a scheduled Cesarean section. Even if there is no definite history of head trauma, it is necessary to consider cephalohematoma when we examine a cranial mass of a neonate.


Assuntos
Encefalopatias , Cesárea , Hematoma , Neoplasias Cranianas , Encefalopatias/diagnóstico por imagem , Encefalopatias/cirurgia , Feminino , Hematoma/diagnóstico por imagem , Hematoma/cirurgia , Humanos , Recém-Nascido , Imageamento por Ressonância Magnética , Gravidez , Crânio , Neoplasias Cranianas/diagnóstico por imagem , Neoplasias Cranianas/cirurgia
8.
Acta Chim Slov ; 61(3): 453-6, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25286200

RESUMO

Using radio frequency - magnetron sputtering, calcium-doped barium zirconate titanate ((Ba(0.85)Ca(0.15))(Zr(0.1)Ti(0.9))O(3), BCZT) thin films were deposited on Si wafers with different bottom electrodes. The obtained BCZT thin film on a lanthanum nickel oxide (LNO) electrode had a highly c-axis preferred orientation, while the BCZT thin film on a Pt bottom electrode had (111) preferred orientation. Furthermore, the out-of-plane lattice constant of the BCZT on LNO/Si was 3.4% larger than that of the reported bulk material because of the compressive thermal stress from LNO with a large thermal expansion coefficient. This compressive thermal stress engenders an increase of the Curie temperature. The local piezoelectric response of the BCZT thin film on a LNO/Si structure was measured by piezoresponse force microscope.

9.
Mass Spectrom (Tokyo) ; 13(1): A0148, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39026546

RESUMO

Electrospray ionization mass spectrometry of neat undiluted ionic liquid (IL) and the analysis of protein with the doping of IL were performed using high-pressure electrospray. The use of disposable micropipette tips as emitters eased the handling of viscous and easy-to-clog samples and improved the reproducibility of the measurement. A high-pressure operation enabled the stable electrospray of the highly conductive IL from these relatively large bore emitters. The measurement of the current-voltage relationship of 1-ethyl-3-methylimidazolium tetrafluoroborate (Emim BF4) revealed an unusual negative differential resistance that has not been seen in the typical atmospheric or high-pressure electrospray. Mass spectrometric analysis of this IL also showed the characteristic response of various ion species with the emitter voltage. When added to the commonly used protein solution, the mass spectrum also showed protein peaks that correspond to the adduction of fluoroboric acid molecules (HBF4).

10.
Chempluschem ; 89(4): e202300480, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37906113

RESUMO

In this article, a deep insight into emulsion radiation-induced graft polymerization (RIGP) was obtained by computing explicit solvation free energies, conformational entropy, monomer radius and dipole moments with the state-of-the-art Conformer-Rotamer Ensemble Sampling Tool (CREST) package primarily at semiempirical GFN-xTB level. By leveraging the robustness of the CREST package, above parameters provided dynamic nature of methacrylate monomers with the consideration of realistic emulsion conditions. With the chemical and physical importance of the above results, CREST-determined explanatory variables sufficiently led to the building of the prediction models for the RIGP of methacrylate monomers. The machine learning model building resulted in effective reactivity predictions and unveiled important factors for the radiation-induced graft polymerization in a chemically interpretable fashion.

11.
Chempluschem ; 89(4): e202400061, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38316619

RESUMO

Invited for this month's cover are the collaborating groups of Dr. Ryohei Kakuchi and Ms. Kiho Matsubara at Gunma University, Japan, Prof. Kei Takahashi at Fukuoka Institute of Technology and The Institute of Statistical Mathematics, Japan, Prof. Takeshi Matsuda at Hannan University, Japan, Dr. Noriaki Seko and Dr. Yuji Ueki at National Institutes for Quantum Science and Technology, Japan. The cover picture shows the machine learning-based optimization and interpretation of radiation-induced graft polymerizations under emulsion conditions based on realistic information for monomers calculated by the state-of-the-art semiempirical method. More information can be found in the Research Article by Kiho Matsubara, Kei Takahashi, Ryohei Kakuchi, and co-workers.

12.
Thyroid ; 33(1): 45-52, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36345221

RESUMO

Background: Macro-thyrotropin (macro-TSH) is a large molecular weight TSH that causes elevated serum TSH concentrations due to its slow clearance. It is primarily a complex of TSH and anti-TSH autoantibodies. The aims of this study were to examine the prevalence and nature of macro-TSH in neonates and to determine how to cope with macro-TSH in neonates suspected to have congenital hypothyroidism through neonatal mass screening. Methods: The presence of macro-TSH was examined using polyethylene glycol (PEG), gel filtration chromatography (GFC), and 125I-TSH binding studies in 939 umbilical cord blood samples from neonates and their mothers. Results: Among 138 serum samples with a PEG precipitation ratio of TSH >68.9% (mean + standard deviation), human anti-mouse antibodies were found in nine samples. The presence of macro-TSH was examined in the remaining 129 serum samples using a 125I-TSH binding study and GFC. The 125I-TSH binding study revealed that four babies (0.43%) had significantly high ratios of 125I-TSH binding to their sera. Two of the babies were siblings, and their mother and the other two mothers also showed significantly high binding ratios. The 125I-TSH binding was displaced by a large amount (1 µg) of unlabeled human TSH in a similar way between babies and their mothers in all cases, suggesting the presence of anti-TSH autoantibodies in their sera. Further characterization of the autoantibodies in one baby and its mother showed a low affinity and high specificity to human TSH, and the nature was very similar between them. These findings may indicate that the anti-TSH autoantibodies that developed in the mother were transferred to the baby through the placenta and formed macro-TSH by binding to neonatal TSH. GFC revealed macro-TSH in only one baby and its mother, probably because of the dissociation of TSH from autoantibodies during the analytical procedure. Conclusions: Macro-TSH was found in 0.43% of neonates, and their mothers all had macro-TSH as well. We recommend that if a baby's serum TSH concentration is high enough to consider levothyroxine treatment suspecting congenital hypothyroidism but the free thyroxine level is normal, their mother's macro-TSH should be checked.


Assuntos
Hipotireoidismo Congênito , Tireotropina , Feminino , Gravidez , Recém-Nascido , Humanos , Hipotireoidismo Congênito/diagnóstico , Mães , Sangue Fetal , Prevalência , Tiroxina , Autoanticorpos
13.
J Am Soc Mass Spectrom ; 34(4): 728-736, 2023 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-36815710

RESUMO

A bipolar ESI source is developed to generate a simultaneous emission of charged liquid jets of opposite polarity from an electrodeless sprayer. The sprayer consists of two emitters, and the electrosprays are initiated by applying a high potential difference (HV) across the counter electrodes facing each emitter. The sprayer and the liquid delivery system are made of all insulators without metal components, thus enabling the total elimination of electrochemical reactions taking place at the liquid-electrode interface in the typical electrosprayer. The bipolar electrospray has been implemented using an online configuration that uses a syringe pump for flow rate regulation and an offline configuration that relies on HV for adjusting the flow rate. The voltage-current and flow rate-current relationships of bipolar electrospray were found to be similar to the standard electrospray. The application of bipolar ESI to the mass spectrometry of protein, peptide, and metallocene without electrochemically induced oxidation/reduction is demonstrated.

14.
Chem Sci ; 14(17): 4506-4515, 2023 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-37152264

RESUMO

Oxidative modification is usually used in mass spectrometry (MS) for labeling and structural analysis. Here we report a highly tunable oxidation that can be performed in line with the nanoESI-MS analysis at the same ESI emitter without the use of oxidative reagents such as ozone and H2O2, and UV activation. The method is based on the high-pressure nanoESI of a highly conductive (conductivity >3.8 S m-1) aqueous solution near the minimum flow rate. The ion source is operated under super-atmospheric pressure (0.5 MPa gauge pressure) to avoid the contribution of electric discharge. The analyte at the tip of the Taylor cone or in the emitter droplet can be locally oxidized in an on-demand manner by varying the nanoflow rate. With an offline nanoESI, the degree of oxidation, i.e., the average number of incorporated oxygen atoms, can be finely tuned by voltage modulation using spray current as the feedback signal. Oxidations of easily oxidized residues present in peptides/proteins and the double bonds of the unsaturated phosphatidylcholine occur at low flow rate operation (<5 nL min-1) when the electric field at the tip of the Taylor cone and the initially produced charged droplet reaches approximately 1.3 V nm-1. The oxidized ion signal responds instantaneously to changes in flow rate, indicating that the oxidation is highly localized. Using isotope labeling, it was found that the incorporated oxygen primarily originates from the gas phase, suggesting a direct oxidation pathway for the analyte enriched on the liquid surface via the reactive oxygen atoms formed by the strong electric field.

15.
J Mol Endocrinol ; 69(1): 259-268, 2022 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-35354667

RESUMO

Telmisartan and irbesartan are angiotensin II receptor blockers (ARBs) and reportedly stimulate adiponectin secretion from adipocytes via partial peroxisome proliferator-activated receptor γ (PPARγ) activation. However, quantitative evaluation among different ARBs has not been performed. Adiponectin exerts strong protection against a number of pathological events by suppressing cell death, inhibiting inflammation, and enhancing cell survival, while leptin promotes inflammation, oxidative stress, atherogenesis, and thrombosis. The aim of this study was to identify the most effective ARB enhancing adiponectin secretion without raising leptin secretion from human white adipocytes (HWAs). Among seven ARBs (azilsartan, candesartan, irbesartan, losartan, olmesartan, telmisartan, and valsartan), telmisartan was the most effective ARB for the increase of adiponectin secretion and irbesartan was the second, whereas the other ARBs at 1 µM had no effect on adiponectin secretion. GW9662, a PPARγ antagonist, completely blocked pioglitazone (PPARγ agonist)-induced adiponectin secretion and mRNA expression, whereas it unexpectedly blocked neither telmisartan- nor irbesartan-induced adiponectin secretion and mRNA expression but rather increased them. GW6471, PPARα antagonist, and siRNA for PPARα suppressed telmisartan- and irbesartan-induced adiponectin secretion, suggesting that PPARα is the main target of these ARBs to increase adiponectin secretion in HWAs. Leptin secretion was not affected by any ARBs at 1 µM and GW9662 significantly decreased the basal secretion of leptin, suggesting that basal leptin secretion is regulated in a PPARγ-dependent manner. We conclude that telmisartan is the most effective ARB to increase adiponectin secretion via PPARα without raising leptin secretion from HWAs.


Assuntos
Adiponectina , Antagonistas de Receptores de Angiotensina , Adipócitos/metabolismo , Adiponectina/metabolismo , Bloqueadores do Receptor Tipo 1 de Angiotensina II/metabolismo , Bloqueadores do Receptor Tipo 1 de Angiotensina II/farmacologia , Antagonistas de Receptores de Angiotensina/metabolismo , Antagonistas de Receptores de Angiotensina/farmacologia , Inibidores da Enzima Conversora de Angiotensina/metabolismo , Inibidores da Enzima Conversora de Angiotensina/farmacologia , Benzoatos/metabolismo , Benzoatos/farmacologia , Humanos , Inflamação/metabolismo , Irbesartana/farmacologia , Leptina/metabolismo , PPAR alfa/metabolismo , PPAR gama/metabolismo , RNA Mensageiro/metabolismo , Telmisartan/metabolismo , Telmisartan/farmacologia
16.
RSC Adv ; 12(37): 24427-24438, 2022 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-36128544

RESUMO

Catalysts for the oxygen evolution reaction (OER) are receiving great interest since OER remains the bottleneck of water electrolyzers for hydrogen production. Especially, OER in acidic solutions is crucial since it produces high current densities and avoids precipitation of carbonates. However, even the acid stable iridates undergo severe dissolution during the OER. BaIrO3 has the strongest IrO6 connectivity and stable surface structure, yet it suffers from lattice collapse after OER cycling, making it difficult to improve the OER durability. In the present study, we have successfully developed an OER catalyst with both high intrinsic activity and stability under acidic conditions by preventing the lattice collapse after repeated OER cycling. Specifically, we find that the substitution of Ir-site with Mn for BaIrO3 in combination with OER cycling leads to a remarkable activity enhancement by a factor of 28 and an overall improvement in stability. This dual enhancement of OER performance was accomplished by the novel strategy of slightly increasing the Ir-dissolution and balancing the elemental dissolution in BaIr1-x Mn x O3 to reconstruct a rigid surface with BaIrO3-type structure. More importantly, the mass activity for BaIr0.8Mn0.2O3 reached ∼73 times of that for IrO2, making it a sustainable and promising OER catalyst for energy conversion technologies.

17.
Surg Neurol Int ; 12: 16, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33500831

RESUMO

BACKGROUND: Thrombosed intracranial aneurysm (IA) is likely to occur in large or giant IAs. Almost all thrombosed IAs are found already in a thrombosed state, and few reports have depicted the process of thrombosis in unthrombosed aneurysm. Moreover, no reports appear to have described IA in which thrombosis accelerated after trauma. CASE DESCRIPTION: We report herein a case in which an unthrombosed large cerebral aneurysm rapidly thrombosed and grew within 3 months after trauma. The highlight in this unusual case was that during surgery, the aneurysm and anterior skull base were adherent and some blood vessels bridged between the aneurysm and dura mater. Histologically, intramural hemorrhage was seen in the tunica media of the aneurysm. CONCLUSION: Trauma may act as a "second hit" causing adhesion between IAs and surrounding tissues, accelerating inflammation of the vasa vasorum and aneurysmal walls, and thrombosis in IAs.

18.
Surg Neurol Int ; 12: 389, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34513156

RESUMO

BACKGROUND: Preservation of the lenticulostriate artery (LSA) is crucial. LSAs usually cannot be spared with LSA aneurysms, when surgical clipping/excision or endovascular embolization of the LSA itself is performed. On the other hand, the LSA should be separated and preserved for proximal middle cerebral artery (M1)-LSA aneurysms. CASE DESCRIPTION: We report a case of M1-LSA aneurysm with native radiological examinations suggesting LSA aneurysm. The highlight of this unusual case was that during surgery, the aneurysm orifice was almost covered with thrombus and blood flow in an aneurysm that appeared separate from M1. Partial thrombectomy-clip reconstruction was performed, and M1 and LSAs were well preserved. CONCLUSION: Even with currently developed radiological modalities, thrombosed intracranial aneurysms may be misdiagnosed, depending on intraluminal flow conditions. Intraoperative findings from craniotomy sometimes contribute to a better understanding of the pathophysiology and decisions on appropriate treatment strategy.

19.
Nat Commun ; 12(1): 2074, 2021 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-33824316

RESUMO

Thiazoline-related innate fear-eliciting compounds (tFOs) orchestrate hypothermia, hypometabolism, and anti-hypoxia, which enable survival in lethal hypoxic conditions. Here, we show that most of these effects are severely attenuated in transient receptor potential ankyrin 1 (Trpa1) knockout mice. TFO-induced hypothermia involves the Trpa1-mediated trigeminal/vagal pathways and non-Trpa1 olfactory pathway. TFOs activate Trpa1-positive sensory pathways projecting from trigeminal and vagal ganglia to the spinal trigeminal nucleus (Sp5) and nucleus of the solitary tract (NTS), and their artificial activation induces hypothermia. TFO presentation activates the NTS-Parabrachial nucleus pathway to induce hypothermia and hypometabolism; this activation was suppressed in Trpa1 knockout mice. TRPA1 activation is insufficient to trigger tFO-mediated anti-hypoxic effects; Sp5/NTS activation is also necessary. Accordingly, we find a novel molecule that enables mice to survive in a lethal hypoxic condition ten times longer than known tFOs. Combinations of appropriate tFOs and TRPA1 command intrinsic physiological responses relevant to survival fate.


Assuntos
Medo/fisiologia , Hipotermia/metabolismo , Hipóxia/metabolismo , Canal de Cátion TRPA1/metabolismo , Tiazóis/farmacologia , Animais , Bradicardia/patologia , Medo/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Células HEK293 , Humanos , Hipotermia/complicações , Hipóxia/complicações , Masculino , Camundongos Endogâmicos C57BL , Neurônios/efeitos dos fármacos , Consumo de Oxigênio/efeitos dos fármacos , Sensação/efeitos dos fármacos , Tiazóis/química , Fatores de Tempo , Gânglio Trigeminal/efeitos dos fármacos , Gânglio Trigeminal/metabolismo , Nervo Vago/efeitos dos fármacos
20.
Sci Rep ; 10(1): 15932, 2020 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-32985609

RESUMO

Leptin and adiponectin are produced mainly in adipocytes and classified as adipocytokines because of their possible involvement in inflammation and immunity. The aim of this study was to elucidate the relationships of these adipocytokines with the disease activities of RA. We examined leptin and adiponectin concentrations and inflammatory markers such as metalloproteinase-3 (MMP-3) in 136 patients with rheumatoid arthritis (RA) (26 males and 110 females, 69.6 ± 9.3 years) and 78 controls (36 males and 42 females, 66.7 ± 15.0 years). Serum leptin and adiponectin concentrations correlated positively (r = 0.565, P < 0.001) and negatively (r = -0.331, P < 0.001) to the amount of body fat, respectively. Serum leptin and adiponectin concentrations normalized by body fat mass were significantly higher in RA than those in controls [leptin, 1.24 (median) ng/mL/kg fat in RA vs. 0.76 ng/mL/kg fat in controls; adiponectin, 0.74 µg/mL/kg fat in RA vs. 0.44 µg/mL/kg fat in controls]. Normalized adiponectin concentrations correlated positively not only to the degree of bone destruction in Steinbrocker classification but also to serum MMP-3 concentrations. Normalized leptin concentrations did not correlate to the degree of bone destruction. We conclude that adiponectin but not leptin may be involved in joint damage in RA.


Assuntos
Adiponectina/sangue , Artrite Reumatoide/diagnóstico , Biomarcadores/sangue , Índice de Massa Corporal , Leptina/sangue , Metaloproteinase 3 da Matriz/sangue , Idoso , Artrite Reumatoide/sangue , Estudos de Casos e Controles , Estudos de Avaliação como Assunto , Feminino , Humanos , Masculino , Padrões de Referência
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