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1.
Int J Mol Sci ; 25(4)2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38397020

RESUMO

Anserine, an imidazole dipeptide, is present in the muscles of birds and fish and has various bioactivities, such as anti-inflammatory and anti-fatigue effects. However, the effect of anserine on the development of heart failure remains unknown. We cultured primary cardiomyocytes with 0.03 mM to 10 mM anserine and stimulated them with phenylephrine for 48 h. Anserine significantly suppressed the phenylephrine-induced increases in cardiomyocyte hypertrophy, ANF and BNP mRNA levels, and histone H3K9 acetylation. An in vitro histone acetyltransferase (HAT) assay showed that anserine directly suppressed p300-HAT activity with an IC50 of 1.87 mM. Subsequently, 8-week-old male C57BL/6J mice were subjected to transverse aortic constriction (TAC) and were randomly assigned to receive daily oral treatment with anserine-containing material, Marine Active® (60 or 200 mg/kg anserine) or vehicle for 8 weeks. Echocardiography revealed that anserine 200 mg/kg significantly prevented the TAC-induced increase in left ventricular posterior wall thickness and the decrease in left ventricular fractional shortening. Moreover, anserine significantly suppressed the TAC-induced acetylation of histone H3K9. These results indicate that anserine suppresses TAC-induced systolic dysfunction, at least in part, by inhibiting p300-HAT activity. Anserine may be used as a pharmacological agent for human heart failure therapy.


Assuntos
Anserina , Cardiomiopatias , Insuficiência Cardíaca , Miócitos Cardíacos , Fatores de Transcrição de p300-CBP , Animais , Humanos , Masculino , Camundongos , Acetilação , Anserina/farmacologia , Cardiomegalia/genética , Cardiomiopatias/metabolismo , Inibidores Enzimáticos/farmacologia , Insuficiência Cardíaca/metabolismo , Histonas/metabolismo , Camundongos Endogâmicos C57BL , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Fenilefrina/farmacologia , Fatores de Transcrição de p300-CBP/antagonistas & inibidores
2.
Toxicol Appl Pharmacol ; 466: 116472, 2023 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-36934860

RESUMO

Sodium nitrite (NaNO2) is a universal antidote for patients with cyanide poisoning. However, its use has serious drawbacks in terms of efficacy and safety. Herein, we present a promising antidote: methemoglobin (metHb)-albumin clusters. The metHb-albumin cluster is made by a metHb core wrapped by covalently bound human serum albumin. Spectral analyses proved that the metHb-albumin clusters possessed cyanide-binding properties similar to those of naked metHb. In vitro cell experiments showed that metHb-albumin clusters prevented the cyanide-induced inhibition of cytochrome c oxidase activity, resulting in a strong cytoprotective effect. In mice subjected to cyanide poisoning, metHb-albumin clusters reduced mortality and alleviated metabolic acidosis, while maintaining the activity of cytochrome c oxidase in organs; their efficacy was better than that of NaNO2. Furthermore, the oxygen carrying capacity was maintained in poisoned mice treated with metHb-albumin clusters and was low in those treated with NaNO2. These results indicate that metHb-albumin clusters could be a more effective and safer antidote against cyanide poisoning than NaNO2.


Assuntos
Cianetos , Metemoglobina , Humanos , Camundongos , Animais , Metemoglobina/análise , Metemoglobina/química , Metemoglobina/metabolismo , Cianetos/metabolismo , Antídotos/farmacologia , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Albuminas/metabolismo
3.
Toxicol Appl Pharmacol ; 481: 116752, 2023 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-37956930

RESUMO

Methemoglobin (metHb), the oxidized form of hemoglobin, lacks the ability of reversible oxygen binding; however, it has a high binding affinity to toxic substances such as cyanide, hydrosulfide, and azide. This innate property of metHb offers the clinical option to treat patients poisoned with these toxins, by oxidizing the endogenous hemoglobin in the red blood cells (RBCs). The binding properties of naked metHb (isolated from RBC) with these toxins has been studied; however, the binding behaviors of metHb under the intracellular conditions of RBC are unclear because of the difficulty in detecting metHb status changes in RBC. This study aimed to elucidate the binding properties of metHb in RBC under physiological and poisoned conditions using artificial RBC, which was hemoglobin encapsulated in a liposome. The mimic-circumstances of metHb in RBC (metHb-V) was prepared by oxidizing the hemoglobin in artificial RBC. Spectroscopic analysis indicated that the metHb in metHb-V exhibited a binding behavior different from that of naked metHb, depending on the toxic substance: When the pH decreased, (i) the cyanide binding affinity of metHb-V remained unchanged, but that of naked metHb decreased (ii) the hydrosulfide binding affinity was increased in metHb-V but was decreased in naked metHb. (iii) Azide binding was increased in metHb-V, which was similar to that in naked metHb, irrespective of the pH change. Thus, the binding behavior of intracellular metHb in the RBC with cyanide, hydrosulfide, and azide under physiological and pathological conditions were partly elucidated using the oxidized artificial RBC.


Assuntos
Azidas , Metemoglobina , Humanos , Metemoglobina/análise , Metemoglobina/química , Metemoglobina/metabolismo , Azidas/análise , Azidas/metabolismo , Cianetos/toxicidade , Cianetos/análise , Cianetos/metabolismo , Eritrócitos/metabolismo , Hemoglobinas/análise , Hemoglobinas/metabolismo
4.
BMC Pregnancy Childbirth ; 23(1): 332, 2023 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-37161480

RESUMO

BACKGROUND: mRNA vaccination is an effective, safe, and widespread strategy for protecting pregnant women against infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. However, information on factors such as perinatal outcomes, safety, and coverage of mRNA vaccinations among pregnant women is limited in Japan. Therefore, this study aimed to investigate the perinatal outcomes, coverage, adverse effects, and short-term safety of mRNA vaccination as well as vaccine hesitancy among pregnant women. METHODS: We conducted a multicenter online survey of postpartum women who delivered their offspring at 15 institutions around Tokyo from October 2021 to March 2022. Postpartum women were divided into vaccinated and unvaccinated groups. Perinatal outcomes, COVID-19 prevalence, and disease severity were compared between the two groups. Adverse reactions in the vaccinated group and the reasons for being unvaccinated were also investigated retrospectively. RESULTS: A total of 1,051 eligible postpartum women were included. Of these, 834 (79.4%) had received an mRNA vaccine, while 217 (20.6%) had not, mainly due to concerns about the effect of vaccination on the fetus. Vaccination did not increase the incidence of adverse perinatal outcomes, including fetal morphological abnormalities. The vaccinated group demonstrated low COVID-19 morbidity and severity. In the vaccinated group, the preterm birth rate, cesarean section rate, and COVID-19 incidence were 7.2%, 33.2%, and 3.3%, respectively, compared with the 13.7%, 42.2%, and 7.8% in the unvaccinated group, respectively. Almost no serious adverse reactions were associated with vaccination. CONCLUSIONS: mRNA vaccines did not demonstrate any adverse effects pertaining to short-term perinatal outcomes and might have prevented SARS-CoV-2 infection or reduced COVID-19 severity. Concerns regarding the safety of the vaccine in relation to the fetus and the mother were the main reasons that prevented pregnant women from being vaccinated. To resolve concerns, it is necessary to conduct further research to confirm not only the short-term safety but also the long-term safety of mRNA vaccines.


Assuntos
COVID-19 , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Nascimento Prematuro , Recém-Nascido , Gravidez , Feminino , Humanos , Japão/epidemiologia , Gestantes , Cesárea , Estudos Retrospectivos , COVID-19/epidemiologia , COVID-19/prevenção & controle , SARS-CoV-2 , Nascimento Prematuro/epidemiologia , Vacinação/efeitos adversos , Inquéritos e Questionários
5.
Invest New Drugs ; 40(5): 934-943, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35759133

RESUMO

ABCC10/MRP7, an ATP-binding cassette (ABC) transporter, has been implicated in the extracellular transport of taxanes. Our group reported that the ABCC10 single nucleotide polymorphism (SNPs), rs2125739, influences docetaxel cytotoxicity in lung cancer cell lines as well as its side effects in clinical practice. In this study, we investigated whether the rs2125739 variant could affect paclitaxel (PTX) cytotoxicity in lung cancer cell lines. We also investigated the effect of rs2125739 on the efficacy and safety of nanoparticle albumin-bound PTX (nab-PTX) in clinical practice. The association between rs2125739 genotypes and the 50% inhibitory concentration (IC50) of PTX was investigated in 18 non-small cell lung cancer (NSCLC) cell lines, HeLa cells, and genome-edited HeLa cells. Next, blood samples from 77 patients with NSCLC treated with carboplatin plus nab-PTX were collected and analyzed for six SNPs, including rs2125739. The clinical outcomes among the different genotype groups were evaluated. In NSCLC cell lines, HeLa cells, and genome-edited HeLa cells, the IC50 was significantly higher in the ABCC10 rs2125739 T/T group than in the T/C and C/C groups. In 77 patients with NSCLC, there were no significant differences in clinical outcomes between the T/T and T/C groups. However, the rs2125739 T/T genotype was associated with a higher frequency of Grades 3/4 neutropenia. In contrast, there was no association between other SNPs and clinical efficacy or neutropenia. Our results indicate that the ABCC10 rs2125739 variant is associated with neutropenia in response to nab-PTX treatment.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Nanopartículas , Neutropenia , Transportadores de Cassetes de Ligação de ATP/genética , Paclitaxel Ligado a Albumina/uso terapêutico , Albuminas/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Variação Genética , Células HeLa , Humanos , Japão , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Proteínas Associadas à Resistência a Múltiplos Medicamentos/genética , Proteínas Associadas à Resistência a Múltiplos Medicamentos/uso terapêutico , Neutropenia/induzido quimicamente , Paclitaxel/efeitos adversos
6.
Toxicol Appl Pharmacol ; 450: 116159, 2022 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-35803436

RESUMO

Hydrogen sulfide (H2S) induces acute and lethal toxicity at high concentrations. However, no specific antidotes for H2S poisoning have been approved. Liposomal methemoglobin (metHb@Lipo) was developed as an antidote for cyanide poisoning. As the toxic mechanism of H2S poisoning is the same as that of cyanide poisoning, metHb@Lipo could potentially be used as an antidote for H2S poisoning. In this study, we evaluated the antidotal efficacy of metHb@Lipo against H2S poisoning. Stopped-flow rapid-scan spectrophotometry clearly showed that metHb@Lipo scavenged H2S rapidly. Additionally, metHb@Lipo showed cytoprotective effects against H2S exposure in H9c2 cells by maintaining mitochondrial function. MetHb@Lipo treatment also improved the survival rate after H2S exposure in vivo, with the maintenance of cytochrome c oxidase activity and suppression of metabolic acidosis. Moreover, metHb@Lipo therapy maintained significant antidotal efficacy even after 1-year-storage at 4-37 °C. In conclusion, metHb@Lipo is a candidate antidote for H2S poisoning.


Assuntos
Sulfeto de Hidrogênio , Intoxicação , Antídotos/farmacologia , Antídotos/uso terapêutico , Cianetos , Humanos , Sulfeto de Hidrogênio/metabolismo , Metemoglobina/metabolismo , Metemoglobina/farmacologia , Intoxicação/tratamento farmacológico
7.
Int J Mol Sci ; 23(4)2022 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-35216044

RESUMO

Hydrogen-bonded organic frameworks (HOFs) have attracted renewed attention as another type of promising candidates for functional porous materials. In most cases of HOF preparation, the applied molecular design principle is based on molecules with rigid π-conjugated skeleton together with more than three H-bonding groups to achieve 2D- or 3D-networked structures. However, the design principle does not always work, but results in formation of unexpected structures, where subtle structural factors of which we are not aware dictate the entire structure of HOFs. In this contribution, we assess recent advances in HOFs, focusing on those composed of hexatopic building block molecules, which can provide robust frameworks with a wide range of topologies and properties. The HOFs described in this work are classified into three types, depending on their H-bonded structural motifs. Here in, we focus on: (1) the chemical aspects that govern their unique fundamental chemistry and structures; and (2) their photophysics at the ensemble and single-crystal levels. The work addresses and discusses how these aspects affect and orient their photonic applicability. We trust that this contribution will provide a deep awareness and will help scientists to build up a systematic series of porous materials with the aim to control both their structural and photodynamical assets.


Assuntos
Ácidos Carboxílicos/química , Humanos , Ligação de Hidrogênio , Porosidade
8.
J Org Chem ; 86(22): 16077-16083, 2021 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-34550701

RESUMO

Electrochemical reduction of N-Boc-α-aminosulfones in DMF using an undivided cell equipped with a Pt plate cathode and an Mg rod anode under atmospheric pressure of bubbling carbon dioxide through the solution under constant current conditions resulted in a reductive C-S bond cleavage with elimination of benzenesulfinate ion generating the corresponding anion species followed by fixation of carbon dioxide to give the corresponding N-Boc-α-amino acids in moderate to good yields.

9.
J Org Chem ; 86(14): 9811-9819, 2021 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-34182754

RESUMO

Carbonate esters are utilized as solvents and reagents for C1 building blocks in organic synthesis. This study reports a novel photo-on-demand in situ synthesis of carbonate esters with CHCl3 solutions containing a mixture of an aromatic or haloalkyl alcohol having relatively high acidity, and an organic base. We found that the acid-base interaction of the alcohol and base in the CHCl3 solution plays a key role in enabling the photochemical reaction. This reaction allows practical syntheses of diphenyl carbonate derivatives, haloalkyl carbonates, and polycarbonates, which are important chemicals and materials in industry.

10.
Chemistry ; 26(71): 17056-17062, 2020 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-32573854

RESUMO

Interpenetration of low-dimensional networked structural motifs crucially affects porosity, stability, and properties of the whole reticular framework. However, varying and controlling the manner of interpenetration is still challenging. Herein, a porous hydrogen-bonded organic framework (HOF) with wvm-like weave constructed by triaxially woven chicken wires of X-shaped tetra-armed tetrakis(carboxybiphenyl)ethene CBPE, formally 4',4''',4''''',4'''''''-(ethene-1,1,2,2-tetrayl)tetrakis(1,1'-biphenyl-4-carboxylic acid), is reported. The structure is a contrast to a non-interpenetrated layered framework composed of tetrakis(4-carboxyphenyl)ethene CPE. This exotic framework of CBPE is due to the disproportionate conformation of the outer four phenylene rings in the peripheral biphenyl arms. The activated framework CBPE-1a exhibits thermal stability up to 220 °C and a BET surface area of 555 m2 g-1 . Additionally, the HOF shows mechanochromic behavior in terms of fluorescence color and quantum efficiency. The achievement of the present HOFs can provide insight into constructing a new type of functional porous organic materials with interwoven network structures.

11.
J Am Chem Soc ; 141(5): 2111-2121, 2019 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-30615836

RESUMO

A porous hydrogen-bonded organic framework (HOF) responsive to acid was constructed from a hexaazatrinaphthylene derivative with carboxyphenyl groups (CPHATN). Precise structures of both 1,2,4-trichlorobenzene solvate [CPHATN-1(TCB)] and activated HOF with permanent porosity (CPHATN-1a) were successfully determined by single-crystalline X-ray diffraction analysis. Permanent porosity of CPHATN-1a was evaluated by gas sorption experiments at low temperature. CPHATN-1a also shows significant thermal stability up to 633 K. Its crystals exhibit a rich photochemistry thanks to intramolecular charge-transfer and interunit proton-transfer reactions. Femtosecond (fs) experiments on crystals demonstrate that these events occur in ≤200 fs and 1.2 ps, respectively. Moreover, single-crystal fluorescence microscopy reveals a shift of the emission spectra most probably as a result of defects and a high anisotropic behavior, reflecting an ordered crystalline structure with a preferential orientation of the molecular dipole moments. Remarkably, CPHATN-1a, as a result of the protonation of pyradyl nitrogen atoms embedded in its π-conjugated core, shows reversible vapor acid-induced color changes from yellow to reddish-brown, which can be also followed by an ON/OFF of its emission. To the best of our knowledge, this is the first HOF that exhibits acid-responsive color changes. The present work provides new findings for developing stimuli responsive HOFs.

12.
Gan To Kagaku Ryoho ; 45(8): 1177-1180, 2018 08.
Artigo em Japonês | MEDLINE | ID: mdl-30158414

RESUMO

A 90-year-old woman was referred to our hospital because of dyspnea with pleural effusion that was detected using a chest X-ray. Pleural fluid cell block specimens from the left pleural effusion were shown to be an adenocarcinoma harboring an epidermal growth factor receptor(EGFR)gene mutation(L858R). Erlotinib was administered and the patient responded to treatment for 15 months. Subsequent re-accumulation of the left pleural effusion was detected, and re-evaluation using cell block specimens revealed EGFR T790M mutation positivity. Osimertinib was initiated and the patient responded to treatment for 11 months. Re-evaluation of the left pleural effusion upon failure of osimertinib treatment revealed EGFR T790M mutation negativity. Hence this report summarizes the case of osimertinib therapy being administered to a 90-year-old patient who had EGFR T790M mutation positivity based on a pleural fluid cell block.


Assuntos
Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/genética , Antineoplásicos/uso terapêutico , Receptores ErbB/genética , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Mutação , Piperazinas/uso terapêutico , Derrame Pleural/terapia , Acrilamidas , Adenocarcinoma/complicações , Adenocarcinoma de Pulmão , Idoso de 80 Anos ou mais , Compostos de Anilina , Feminino , Humanos , Neoplasias Pulmonares/complicações , Derrame Pleural/etiologia
13.
Angew Chem Int Ed Engl ; 57(39): 12650-12655, 2018 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-29885200

RESUMO

Enhancing thermal and chemical durability and increasing surface area are two main directions for the construction and improvement of the performance of porous hydrogen-bonded organic frameworks (HOFs). Herein, a hexaazatriphenylene (HAT) derivative that possesses six carboxyaryl groups serves as a suitable building block for the systematic construction of thermally and chemically durable HOFs with high surface area through shape-fitted docking between the HAT cores and interpenetrated three-dimensional network. A HAT derivative with carboxybiphenyl groups forms a stable single-crystalline porous HOF that displays protic solvent durability, even in concentrated HCl, heat resistance up to 305 °C, and a high Brunauer-Emmett-Teller surface area [SA(BET) ] of 1288 m2 g-1 . A single crystal of this HOF displays anisotropic fluorescence, which suggests that it would be applicable to polarized emitters based on robust functional porous materials.

14.
Mycoses ; 60(11): 728-735, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28699245

RESUMO

Although anti-fungal triazoles are dosed orally or systemically for Aspergillus fumigatus infection, systemic adverse events and limited exposure of the lung cavity would make a topical treatment for the lung an attractive option. In this study, we examined the effects of intranasally dosed posaconazole on survival rates and biomarkers in A. fumigatus (itraconazole susceptible: ATCC13073 [Af]; or resistant: NCPF7100 [AfR]) infected, temporarily neutropenic A/J mice. Once daily treatment produced a dose-dependent improvement of survival of Af-infected mice (ED50 : 0.019 mg/mouse [approx. 0.755 mg/kg, in]), similar to its potency (ED50 : 0.775 mg/kg, po) after once daily oral dosing. For AfR infection, either intranasal or oral posaconazole was largely ineffective on survival, although the highest dose of intranasal treatment (0.35 mg/mouse) achieved 75% survival rate. Early intervention (treated on days 0, 1, 2 and 3 postinfection) and late intervention (treated on days 1, 2 and 3) with intranasal posaconazole (0.014-0.35 mg/mouse) demonstrated potent inhibition of lung fungal load and galactomannan levels in both bronchoalveolar lavage fluid (BALF) and serum as well as inflammatory cells, IFN-γ, IL-17 and malondialdehyde (MDA) in BALF. Thus, posaconazole when dosed intranasally once daily showed an improvement of survival equivalent to or better than oral treatment, and produced potent inhibition of fungal load and biomarkers.


Assuntos
Antifúngicos/farmacologia , Aspergilose/tratamento farmacológico , Aspergillus fumigatus/efeitos dos fármacos , Mananas/análise , Triazóis/farmacologia , Administração Intranasal , Administração Oral , Animais , Aspergilose/microbiologia , Aspergilose/patologia , Biomarcadores/análise , Citocinas/análise , Modelos Animais de Doenças , Farmacorresistência Fúngica , Galactose/análogos & derivados , Humanos , Hospedeiro Imunocomprometido , Itraconazol/farmacologia , Pulmão/microbiologia , Masculino , Camundongos , Testes de Sensibilidade Microbiana , Organismos Livres de Patógenos Específicos
15.
Kekkaku ; 91(5): 489-494, 2016 May.
Artigo em Japonês | MEDLINE | ID: mdl-28661589

RESUMO

With the recent decrease in the number of tuberculosis wards and increase in elderly tuber- culosis patients with comorbidities, the role of regional refer- ral hospitals has become more important in tuberculosis management. [Objective]. This study aimed to assess the current state of tuberculosis management and related issues in a general hospital lacking a tuberculosis ward. [Methods] We retrospectively evaluated the clinical char- acteristics and course of patients diagnosed with tuberculosis by culture testing from April 2008 to March 2015 at Kainan Hospital. [Results] A total of 146 patients (83 males and 63 females; mean age 76, range 18-94 years) were diagnosed with active tuberculosis. Of these, 129 were diagnosed with pulmonary tuberculosis (23 had pulmonary tuberculosis with pleurisy), and 17 patients were diagnosed with extrapulmonary tuber- culosis. The chief complains were cough/sputum in 40 cases, fever in 24, and no symptoms in 36. Associated major comorbidities included diabetes mellitus, chronic kidney disease, and malignancy. In 33 patients, over 30 days were required to diagnose tuberculosis after initial evaluation. Drug-resistant strains were detected in 14 patients. 57 were diagnosed with smear-positive pulmonary tuberculosis, and 66 were transferred to a tuberculosis hospital. Modify in anti- tuberculosis therapy due to adverse reactions were reported in 27 patients. [Conclusion] This study evaluated the current state of tuberculosis management in our hospital. Further educational guidance regarding tuberculosis is needed for the hospital staff, and is important for improvement of tuberculosis management in our hospital.


Assuntos
Hospitais Gerais/estatística & dados numéricos , Tuberculose/diagnóstico , Tuberculose/epidemiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Japão , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
16.
J Am Chem Soc ; 137(9): 3291-9, 2015 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-25712566

RESUMO

There are two types of membrane-embedded ion transport machineries in nature. The ion pumps generate electrochemical potential by energy-coupled active ion transportation, while the ion channels produce action potential by stimulus-dependent passive ion transportation. About 80% of the amino acid residues of the light-driven proton pump archaerhodopsin-3 (AR3) and the light-gated cation channel channelrhodopsin (ChR) differ although they share the close similarity in architecture. Therefore, the question arises: How can these proteins function differently? The absorption maxima of ion pumps are red-shifted about 30-100 nm compared with ChRs, implying a structural difference in the retinal binding cavity. To modify the cavity, a blue-shifted AR3 named AR3-T was produced by replacing three residues located around the retinal (i.e., M128A, G132V, and A225T). AR3-T showed an inward H(+) flux across the membrane, raising the possibility that it works as an inward H(+) pump or an H(+) channel. Electrophysiological experiments showed that the reverse membrane potential was nearly zero, indicating light-gated ion channeling activity of AR3-T. Spectroscopic characterization of AR3-T revealed similar photochemical properties to some of ChRs, including an all-trans retinal configuration, a strong hydrogen bond between the protonated retinal Schiff base and its counterion, and a slow photocycle. From these results, we concluded that the functional determinant in the H(+) transporters is localized at the center of the membrane-spanning domain, but not in the cytoplasmic and extracellular domains.


Assuntos
Bombas de Próton/química , Rodopsina/química , Rodopsina/metabolismo , Animais , Membrana Celular/metabolismo , Citoplasma/metabolismo , Feminino , Halorrodopsinas/química , Interações Hidrofóbicas e Hidrofílicas , Luz , Mutação , Oócitos/metabolismo , Bombas de Próton/metabolismo , Prótons , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Retinaldeído/metabolismo , Rodopsina/genética , Rodopsinas Microbianas/química , Rodopsinas Microbianas/genética , Rodopsinas Microbianas/metabolismo , Rodopsinas Sensoriais/química , Espectroscopia de Infravermelho com Transformada de Fourier , Relação Estrutura-Atividade , Xenopus
17.
Appl Environ Microbiol ; 80(18): 5866-73, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25038092

RESUMO

Phosphotriesterases catalyze the first step of organophosphorus triester degradation. The bacterial phosphotriesterases purified and characterized to date hydrolyze mainly aryl dialkyl phosphates, such as parathion, paraoxon, and chlorpyrifos. In this study, we purified and cloned two novel phosphotriesterases from Sphingomonas sp. strain TDK1 and Sphingobium sp. strain TCM1 that hydrolyze tri(haloalkyl)phosphates, and we named these enzymes haloalkylphosphorus hydrolases (TDK-HAD and TCM-HAD, respectively). Both HADs are monomeric proteins with molecular masses of 59.6 (TDK-HAD) and 58.4 kDa (TCM-HAD). The enzyme activities were affected by the addition of divalent cations, and inductively coupled plasma mass spectrometry analysis suggested that zinc is a native cofactor for HADs. These enzymes hydrolyzed not only chlorinated organophosphates but also a brominated organophosphate [tris(2,3-dibromopropyl) phosphate], as well as triaryl phosphates (tricresyl and triphenyl phosphates). Paraoxon-methyl and paraoxon were efficiently degraded by TCM-HAD, whereas TDK-HAD showed weak activity toward these substrates. Dichlorvos was degraded only by TCM-HAD. The enzymes displayed weak or no activity against trialkyl phosphates and organophosphorothioates. The TCM-HAD and TDK-HAD genes were cloned and found to encode proteins of 583 and 574 amino acid residues, respectively. The primary structures of TCM-HAD and TDK-HAD were very similar, and the enzymes also shared sequence similarity with fenitrothion hydrolase (FedA) of Burkholderia sp. strain NF100 and organophosphorus hydrolase (OphB) of Burkholderia sp. strain JBA3. However, the substrate specificities and quaternary structures of the HADs were largely different from those of FedA and OphB. These results show that HADs from sphingomonads are novel members of the bacterial phosphotriesterase family.


Assuntos
Hidrolases de Triester Fosfórico/isolamento & purificação , Sphingomonadaceae/enzimologia , Sequência de Aminoácidos , Clonagem Molecular , Coenzimas/análise , Hidrocarbonetos Bromados/metabolismo , Hidrocarbonetos Clorados/metabolismo , Hidrólise , Espectrometria de Massas , Dados de Sequência Molecular , Peso Molecular , Organofosfatos/metabolismo , Hidrolases de Triester Fosfórico/química , Conformação Proteica , Análise de Sequência de DNA , Homologia de Sequência , Especificidade por Substrato , Zinco/análise
18.
Soft Matter ; 10(32): 5869-77, 2014 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-24866557

RESUMO

When a chiral liquid crystal is given a transport current, a unidirectional molecular motion is known to take place, which is called the Lehmann effect. In this paper, we study the mysterious heat-current-driven Lehmann effect using two types of hemispherical cholesteric droplets using polarizing, reflecting, confocal and fluorescent microscopies. Both the droplets, coexisting with the isotropic phase and contacting on a glass substrate, are characterized by the concavo-convex modulated surface and the inside orientational helix. Further, the only difference between them is the helical axis direction; i.e., one is perpendicular and the other is parallel to the substrate. Under the temperature gradient perpendicular to the substrate, the droplet whose helical axis is parallel to the heat current exhibited pure director rotation, while that with the axis perpendicular to the current rotated independently as a rigid body. In the two droplets, the rotational conversion efficiency from the temperature gradient into the angular velocity showed very different dependences on the chirality strength and on the droplets' size, suggesting that the rotations of the two droplets may be driven by independent torques with different origins. This is the first observation that the cholesteric droplets under the temperature gradient exhibit the two rotational modes, the pure director rotation and the molecular barycentric motion, which can be switched to each other by changing the heat-current direction parallel and perpendicular to the helical axis.

19.
World J Clin Cases ; 12(14): 2342-2349, 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38765755

RESUMO

BACKGROUND: Helicobacter pylori (H. pylori) infection is closely related to the development of gastric cancer (GC). However, GC can develop even after H. pylori eradication. Therefore, it would be extremely useful if GC could be predicted after eradication. The Kyoto classification score for gastritis (GA) is closely related to cancer risk. However, how the score for GC changes after eradication before onset is not well understood. AIM: To investigate the characteristics of the progression of Kyoto classification scores for GC after H. pylori eradication. METHODS: Eradication of H. pylori was confirmed in all patients using either the urea breath test or the stool antigen test. The Kyoto classification score of GC patients was evaluated by endoscopy at the time of event onset and three years earlier. In addition, the modified atrophy score was evaluated and compared between the GC group and the control GA group. RESULTS: In total, 30 cases of early GC and 30 cases of chronic GA were evaluated. The pathology of the cancer cases was differentiated adenocarcinoma, except for one case of undifferentiated adenocarcinoma. The total score of the Kyoto classification was significantly higher in the GC group both at the time of cancer onset and three years earlier (4.97 vs 3.73, P = 0.0034; 4.2 vs 3.1, P = 0.0035, respectively). The modified atrophy score was significantly higher in the GC group both at the time of cancer onset and three years earlier and was significantly improved only in the GA group (5.3 vs 5.3, P = 0.5; 3.73 vs 3.1, P = 0.0475, respectively). CONCLUSION: The course of the modified atrophy score is useful for predicting the onset of GC after eradication. Patients with severe atrophy after H. pylori eradication require careful monitoring.

20.
ACS Omega ; 8(25): 22589-22595, 2023 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-37396217

RESUMO

Covalent attachment of a ferric hemoglobin (metHb) core to three human serum albumin molecules to form metHb-albumin clusters has previously been used to develop an antidote for hydrogen sulfide poisoning. Lyophilization is one of the most effective approaches to preserve protein pharmaceuticals with minimum contamination and decomposition. However, there is concern that lyophilized proteins may undergo pharmaceutical alteration on reconstitution. This study investigated the pharmaceutical integrity of metHb-albumin clusters on lyophilization and reconstitution with three clinically available reconstitution fluids, (i) sterile water for injection, (ii) 0.9% sodium chloride injection, and (iii) 5% dextrose injection. The metHb-albumin clusters retained their physicochemical properties and structural integrity on lyophilization and reconstitution with sterile water for injection or 0.9% sodium chloride injection, along with comparable hydrogen sulfide scavenging ability compared to non-lyophilized metHb-albumin clusters. The reconstituted protein completely rescued lethal hydrogen sulfide poisoning in mice. On the other hand, lyophilized metHb-albumin clusters reconstituted with 5% dextrose injection showed physicochemical changes and a higher mortality rate in mice subjected to lethal hydrogen sulfide poisoning. In conclusion, lyophilization represents a potent preservation method for metHb-albumin clusters if either sterile water for injection or 0.9% sodium chloride injection is used for reconstitution.

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