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1.
Chem Asian J ; 19(9): e202400111, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38380801

RESUMO

A stable dialkylgermanone was generated by mixing a solid of the corresponding dialkylgermylene and gaseous N2O. While the dialkylgermanone is marginally persistent in solution and gradually converts to its head-to-tail dimer at room temperature, the addition of THF to the dialkylgermanone provided an isolable THF-coordinated dialkylgermanone. The THF-coordinated dialkylgermanone reacts with H2O, THF, and B(C6F5)3 similar to the corresponding base-free two-coordinate dialkylsilanone. The dialkylgermanone undergoes deoxygenation in the presence of triphenylphosphine to provide the corresponding germylene and olefination upon treatment with phosphaylide Ph3PCHPh to afford the corresponding Ge=C bond compound (germa-Wittig reaction).

2.
Chemistry ; 29(70): e202302479, 2023 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-37720978

RESUMO

The four phenyl groups of 1,1,3,3-tetraphenyl-2,2,4,4-tetrakis(trimethylsilyl)cyclotetrasilane were partially replaced by chlorine atom(s) by successive treatment with trifluoromethanesulfonic acid and lithium chloride. The replacement of all phenyl groups was carried out with hydrogen chloride in the presence of aluminum chloride. The structural features of the resulting mono-, di-, and tetrachlorocyclotetrasilanes were compared by X-ray crystallography.

3.
Chem Asian J ; 18(13): e202300307, 2023 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-37211539

RESUMO

Although carbonyl compounds are activated by the coordination of a Lewis acid to the carbonyl oxygen atom, a similar activation process of R2 Si=O species remains unclear. We report herein the reactions of a silanone (1, Scheme 1) with a series of triarylboranes to afford the corresponding boroxysilanes. Experimental results and computational studies indicate that the electrophilicity of the unsaturated silicon atom is enhanced by the complexation of 1 with triarylboranes, and the subsequent aryl migration from the boron atom to the electrophilic silicon atom proceeds.

4.
Hypertens Res ; 46(5): 1122-1131, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36690809

RESUMO

The aim of this study was to clarify the relationship between fasting and nonfasting serum triglyceride (TG) levels and the incidence of hypertension in a general Japanese population. We conducted a population-based retrospective cohort study using annual health check-up data of residents of Iki City, Nagasaki Prefecture, Japan. A total of 3202 participants without hypertension at baseline were included in the present analysis. TG levels were classified as quartile 1 (<0.82 mmol/L), quartile 2 (0.83-1.13 mmol/L), quartile 3 (1.14-1.70 mmol/L) and quartile 4 (≥1.71 mmol/L) for men, and as quartile 1 (<0.70 mmol/L), quartile 2 (0.71-0.96 mmol/L), quartile 3 (0.97-1.34 mmol/L) and quartile 4 (≥1.35 mmol/L) for women. The outcome was incident hypertension. During an average follow-up of 4.4 years, 983 participants developed hypertension, according to the Cox proportional hazards model. The annual incidence of hypertension increased with an elevation in TG levels for men (5.88% in quartile 1, 8.30% in quartile 2, 7.62% in quartile 3, and 9.82% in quartile 4). This association was significant, even after adjustment for other risk factors: hazard ratio 1.41 [95% CI 1.07-1.85] for quartile 2, 1.30 [0.99-1.71] for quartile 3, and 1.59 [1.22-2.08] for quartile 4 compared with quartile 1 (p = 0.041 for trend). In contrast, there was no clear association between serum TG levels and the incidence of hypertension after adjustment for confounding factors among women (p = 0.240 for trend). High levels of serum TG were associated with the future incidence of hypertension in a general population of Japanese men but were not associated with that in women. Casual serum triglyceride levels and incidence of hypertension in a general Japanese population: ISSA-CKD study.


Assuntos
Hipertensão , Insuficiência Renal Crônica , Masculino , Humanos , Feminino , Incidência , Estudos Retrospectivos , População do Leste Asiático , Triglicerídeos , Fatores de Risco
5.
Angew Chem Int Ed Engl ; 61(20): e202117584, 2022 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-35233899

RESUMO

σ-Type 3-electron-2-center (3e-2c) bonds have been extensively studied as one of the key bonding motifs in radical chemistry and some biological systems. "π-Type 3e-2c-bonded species" that contain a 3e-2c π-bond without an underlying σ-bond framework, however, have been unexplored so far both theoretically and experimentally. Herein, we report the synthesis of the first stable π-type 3e-2c-bonded species, a silicon analogue of a bicyclo[1.1.0]butane radical anion. This compound exhibits an extremely long bridgehead Si-Si bond (3.0638(8) Å) and a strong near-IR absorption at 922 nm in solution which arises from a HOMO→SOMO [π(Si-Si)→π*(Si-Si)] transition. DFT calculations revealed a π-type bonding interaction between the two bridgehead silicon atoms with an unpaired electron mainly delocalized across the corresponding π*-type orbital, which introduces a novel bonding motif for constructing π-electron systems.

6.
J Clin Med ; 11(5)2022 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-35268256

RESUMO

The novel conceptual disease model, the oral-gut axis, which represents the immunomodulatory mutual relationship between oral and gut microbial compartments, has been attracting attention in relation to systemic health issues. We investigated whether this unique crosstalk influences the systemic condition of patients with COVID-19 infections who received extracorporeal membrane oxygenation (ECMO) in the intensive care unit (ICU) during April and December 2020. In this case-control study, patients were divided into two groups according to their survival (total entry size, n = 21; survivors, n = 13; non-survivors, n = 8). Patients were evaluated using the oral assessment guide from Fukuoka University (OAG-F) and the Bristol Stool Form Scale (BSFS) to examine the oral and fecal conditions. A blood-based inflammatory factor, the neutrophil-to-lymphocyte ratio (NLR), was used as an indicator of systemic immunity. The high total OAG-F scores were associated with both elevated BSFS and NLR values, and a mutually positive correlation between BSFS and NLR was observed. This indicated an interplay between oral deterioration, gut dysbiosis, and the impairment of immunity. Furthermore, oral deterioration was more frequently observed in non-survivors on day 14 of ICU admission. In addition, on days 7 and 21 of ICU admission, impaired immunity, reflected by an elevated NLR, was observed in non-survivors. However, the distribution of the gut microbiome-reflected by increased BSFS values-with the time it was examined was not directly observed in non-survivors. Taken together, these findings suggested that oral-gut health may be specifically associated with mortality in COVID-19 patients receiving ECMO in the ICU.

7.
J Clin Hypertens (Greenwich) ; 23(12): 2071-2077, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34806282

RESUMO

We aimed to investigate the association between serum uric acid (SUA) level and development of hypertension as well as the interaction effect of chronic kidney disease (CKD) on this relationship in the general Japanese population. We included 7895 participants aged ≥30 years from the ISSA-CKD study, a population-based retrospective cohort study that used annual health check-up data of residents from Iki Island, Japan. After the exclusion of 1881 with l < 1-year follow-up, 2812 with hypertension at baseline, and 165 with missing information on SUA, a total of 3037 participants were enrolled in this analysis. Participants were divided into four groups according to the quartiles of SUA level at baseline, and multivariable-adjusted hazard ratios for new-onset hypertension were calculated. Stratified analyses were performed for each subgroup (defined by sex, age, alcohol intake, and CKD) to assess the interaction effects. During a mean follow-up period of 4.4 years, 943 participants developed hypertension. The first quartile group was set as the reference group, and the multivariable-adjusted hazard ratios (95% confidence interval) for new-onset hypertension were 1.11 (0.90-1.36) in the second quartile, 1.25 (1.02-1.54) in the third quartile, and 1.35 (1.07-1.70) in the fourth quartile compared with those in the reference group (p = .007 for trend). The stratified analyses showed that the association between SUA and hypertension was significantly stronger in participants with CKD than in those without CKD (p = .035 for interaction). SUA level is an independent risk factor for new-onset hypertension. This tendency was significantly stronger in participants with CKD.


Assuntos
Hipertensão , Hiperuricemia , Insuficiência Renal Crônica , Taxa de Filtração Glomerular , Humanos , Hipertensão/epidemiologia , Hiperuricemia/complicações , Hiperuricemia/epidemiologia , Japão/epidemiologia , Insuficiência Renal Crônica/epidemiologia , Estudos Retrospectivos , Fatores de Risco , Ácido Úrico
8.
Org Lett ; 23(20): 8023-8027, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34613748

RESUMO

1,2,3-Benzodiazaboroles can be conveniently prepared from azobenzenes by a two-step protocol involving electrophilic ortho-borylation with BBr3 and dialkylative cyclization with the Grignard reagent. The methodology provides a diverse range of products equipped with functionalities from azobenzenes containing substituents (Me, t-Bu, F, Cl, Br, I, and OCF3) and a series of Grignard reagents (alkyl- and arylmagnesium reagents). Moreover, this study displays the moderate aromaticity of the B-N-N-containing five-membered ring and mechanistic investigations of the cyclization reaction.

9.
Hypertens Res ; 44(12): 1662-1667, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34552209

RESUMO

The aim of this study was to determine the relationship between eating before bed and the development of hypertension in a general Japanese population. We conducted a population-based retrospective cohort study using annual health check-up data collected from the residents of Iki City, Nagasaki Prefecture, Japan. In total, 2930 participants without hypertension at baseline (mean age 57.0 years, male 42.8%) were included in the present analysis. Eating before bed was defined as eating within 2 h of bedtime. The outcome of this study was incident hypertension (blood pressure ≥140/90 mmHg or initiation of blood pressure-lowering medications). Multivariable-adjusted hazard ratios and 95% confidence intervals (CIs) were estimated using Cox proportional hazards models. During an average follow-up of 4.5 years, 909 participants developed hypertension. The incidence (per 1000 person-years) of hypertension in the group of individuals who ate before bed was 82.8, whereas that in the group of individuals who did not eat before bed was 65.8. The association was significant even after adjusting for other risk factors, including age, sex, current smoking status, current alcohol intake, regular exercise, obesity, elevated blood pressure, diabetes mellitus, and dyslipidemia, with a hazard ratio of 1.23 (95% CI: 1.05-1.44) for the group of individuals who ate before bed compared with the group of individuals who did not eat before bed (P = 0.01 for trend). Eating before bed was correlated with a future risk of developing hypertension in the general Japanese population.


Assuntos
Aterosclerose , Hipertensão , Insuficiência Renal Crônica , Pressão Sanguínea , Humanos , Hipertensão/epidemiologia , Incidência , Japão/epidemiologia , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Insuficiência Renal Crônica/epidemiologia , Estudos Retrospectivos , Fatores de Risco
10.
J Clin Med ; 10(9)2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-34062802

RESUMO

BACKGROUND: We investigated whether eating speed was associated with the incidence of diabetes in a Japanese general population. METHODS: A total of 4853 Japanese individuals without diabetes at baseline were analyzed. Self-reported eating speed was categorized as slow, medium, and fast on the basis of questionnaire responses. The study outcome was the incidence of diabetes. RESULTS: After an average follow-up period of 5.1 years, 234 individuals developed diabetes. The incidence of diabetes per 1000 person-years was 4.9 in the slow eating speed group, 8.8 in the medium eating speed group, and 12.5 in the fast eating speed group, respectively (*** p < 0.001 for trend). The HRs were 1.69 (95%CI 0.94-3.06) for the medium eating speed and 2.08 (95%CI 1.13-3.84) for the fast eating speed, compared to the slow eating speed (* p = 0.014 for trend) after adjustment for age, gender, smoking status, drinking, exercise, obesity, hypertension, and dyslipidemia. CONCLUSION: Faster eating speed increased a risk for the incidence of diabetes in a general Japanese population.

12.
Molecules ; 26(6)2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33804233

RESUMO

π-Electron systems of silicon have attracted attention because of their narrow HOMO-LUMO gap and high reactivity, but the structural diversity remains limited. Herein, new dialkylboryl-substituted disilenes were synthesized by the selective desilylation-borylation of the corresponding trimethylsilyl-substituted disilenes. The dialkylboryl-substituted disilenes were fully characterized by a combination of NMR spectroscopy, MS spectrometry, single-crystal X-ray diffraction analysis, and theoretical calculations. The longest-wavelength absorption bands of boryldisilenes were bathochromically shifted compared to the corresponding silyl-substituted disilenes, indicating a substantial conjugation between π(Si=Si) and vacant 2p(B) orbitals. In the presence of 4-(dimethylamino)pyridine (DMAP), the dialkylboryl groups in the boryl-substituted disilenes were easily converted to trimethylsilyl groups, suggesting the dialkylboryl-substituted disilenes in the presence of a base serve as the surrogates of disilenyl anions (disilenides).

13.
J Am Chem Soc ; 143(7): 2649-2653, 2021 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-33565866

RESUMO

Spiroconjugation, that is, through-space orbital interactions between two perpendicular π orbitals, is a key concept in the contemporary molecular design of spirocyclic π-electron systems. We synthesized spiropentasiladiene radical cation salt 1 as a dark-green solid via the one-electron oxidation of the stable spiropentasiladiene 2. Characterization of the molecular structure combined with theoretical studies indicated that the spin and positive charge are delocalized across the two perpendicular Si═Si double bonds of 1. Two π(Si═Si) orbitals are split into HOMO and SOMO with a small energy gap owing to the second-order Jahn-Teller distortion and steric repulsion between bulky alkyl groups upon one-electron oxidation. In the UV-vis-NIR spectrum, the longest-wavelength absorption band of 1 (λmax = 1972 nm) covers the IR-B region (1400-3000 nm; 0.89-0.41 eV) despite having the smallest possible spiroconjugation motif. The unprecedented absorption band in the IR region was assigned to the HOMO → SOMO transition that arises from the delocalized π-orbitals in the spirocyclic Si5 skeleton.

14.
PLoS One ; 16(2): e0246304, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33529192

RESUMO

OBJECTIVES: This study aimed to clarify the relationship between the white blood cell (WBC) count and hypertension in the general Japanese population. METHODS: We conducted a population-based retrospective cohort study using annual health check-up data of residents of Iki City, Nagasaki Prefecture, Japan. A total of 2935 participants without hypertension at baseline were included in the present analysis. WBC counts were classified as tertile 1 (<4700/µL), tertile 2 (4700-5999/µL), and tertile 3 (≥6000/µL). The outcome was incident hypertension (blood pressure ≥140 mmHg). Multivariable-adjusted hazard ratios and 95% confidence intervals (95% CIs) were estimated using the Cox proportional hazards model. RESULT: During an average follow-up of 4.5 years, 908 participants developed hypertension. The incidence (per 100 person-years) of hypertension increased with an elevation in the WBC count (6.3 in tertile 1, 7.0 in tertile 2, and 7.4 in tertile 3). This association was significant, even after adjustment for other risk factors, including age, sex, current smoking habits, current alcohol intake, exercise habits, obesity, elevated blood pressure, diabetes mellitus, and dyslipidemia. The hazard ratios were 1.07 for tertile 2 (95% CI 0.90-1.26) and 1.27 for tertile 3 (95% CI 1.06-1.51) compared with the reference group of tertile 1 (p = 0.009). CONCLUSION: The WBC count was associated with future development of hypertension in the general Japanese population.


Assuntos
Hipertensão/epidemiologia , Contagem de Leucócitos/tendências , Adulto , Idoso , Pressão Sanguínea , Estudos de Coortes , Feminino , Humanos , Hipertensão/sangue , Incidência , Japão/epidemiologia , Contagem de Leucócitos/métodos , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Fatores de Risco
15.
Dalton Trans ; 50(4): 1413-1421, 2021 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-33433540

RESUMO

An isolable three-coordinate dialkylsilanone without substantial electronic stabilization reacts with several ethers resulting in the cleavage of the C-O or C-H and C-O bonds in the ethers which have not been observed for the hitherto-known electronically stabilised isolable Si[double bond, length as m-dash]O species. The formation of the Lewis base (DMAP and MTHP) complexes of the dialkylsilanone and the DFT calculations elucidated that the coordination of the ethereal oxygen atom to the Lewis acidic Si atom of the genuine Si[double bond, length as m-dash]O bond is a key interaction for the reaction.

16.
Chem Commun (Camb) ; 56(95): 15072-15075, 2020 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-33201948

RESUMO

Naphthodislacyclobutadiene 3 and anthradisilacyclobutadiene 4 were synthesized and characterized. In these compounds, the diatropic ring current on the benzene ring adjacent to the disilacyclobutadiene moiety decreases while that on the other benzene rings remains intact. The longest-wavelength absorption bands of 3 and 4 were hypsochromically shifted compared to those of benzodisilacyclobutadiene 1a despite the extended π-electron systems.

17.
Diagnostics (Basel) ; 10(10)2020 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-33066681

RESUMO

Primary oral diffuse large B cell lymphoma (DLBCL) is rare and the differential diagnosis is difficult due to its low incidence and nonspecific symptoms, which resemble those of common oral diseases in the initial clinical setting. We aimed to discuss the value of making an accurate diagnosis using liquid-based cytology (LBC) and cell block (CB) for not only the morphological interpretation but also cytohistological assessment of oral DLBCL. LBC and CBs made from oral brushing materials were prepared on the first medical examination and a morphological analysis and immunohistochemical analysis of specific biomarkers were performed. The analysis of LBC preparations showed the presence of large-size lymphocytes with large irregular nuclei and prominent nucleoli, suggesting the existence of large B-cell lymphoma. A more detailed histological subclassification of the CB specimen was performed, which was classified as the activated B-cell (ABC) phenotype of DLBCL, by confirming the immunohistochemical expression of CD10-/ B-cell lymphoma 6 (BCL6)+/ multiple myeloma oncogene 1(MUM1)+, which is a significant risk factor in DLBCL. Our findings suggest that the combination of LBC and CB is a useful and informative tool for making an accurate molecular diagnosis of oral DLBCL in cases in which lymphomas are clinically suspected.

18.
Nat Commun ; 11(1): 4009, 2020 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-32782244

RESUMO

A carbon-carbon double bond consists of a σ bond and a π bond. Recently, the concept of a π single bond, where a π bond is not accompanied by a σ bond, has been proposed in diradicals containing carbon and heteroatom radical centers. Here we report a closed-shell compound having a silicon-silicon π single bond. 1,2,2,3,4,4-Hexa-tert-butylbicyclo[1.1.0]tetrasilane has a silicon-silicon π single bond between the bridgehead silicon atoms. The X-ray crystallographic analysis shows that the silicon-silicon π single bond (2.853(1) Å) is far longer than the longest silicon-silicon bond so far reported. In spite of this unusually long bond length, the electrons of the 3p orbitals are paired, which is confirmed by measurement of electron paramagnetic resonance, and magnetic susceptibility and natural bond orbital analysis. The properties of the silicon-silicon π single bond are studied by UV/Vis and 29Si NMR spectroscopy, and theoretical calculations.

20.
J Clin Med Res ; 12(7): 431-435, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32655737

RESUMO

BACKGROUND: There is uncertainty surrounding the causal relationship between serum uric acid and hypertension. The aim was to investigate the association between serum uric acid and prevalence of hypertension in a general population of Japanese. METHODS: This was a population-based cross-sectional study using health check-up data of the residents of the Iki City, Nagasaki Prefecture, Japan. A total of 7,484 participants aged 30 years or older were included in this study. Serum uric acid was classified into four groups: group 1 (< 357 µmol/L (< 6 mg/dL)), group 2 (357 - 415 µmol/L (6 - 6.9 mg/dL)), group 3 (416 - 475 µmol/L (7 - 7.9 mg/dL)) and group 4 (≥ 476 µmol/L (≥ 8 mg/dL)). Hypertension was defined as blood pressure (BP) levels of ≥ 140/90 mm Hg or use of BP lowering medications. RESULTS: Hypertension was observed among 3,467 participants (prevalence 46.3%). The prevalence of hypertension increased with elevation of serum uric acid levels: 42.8% in group 1, 55.0% in group 2, 57.6% in group 3 and 59.8% in group 4 (P < 0.001 for trend). This association was significant even after adjustment for other risk factors including age, sex, current smoking, current alcohol intake, obesity, diabetes, dyslipidemia, estimated glomerular filtration rate and proteinuria: odds ratios (95% confidence intervals) were 1.50 (1.28 - 1.77) for group 2, 1.58 (1.25 - 1.99) for group 3 and 1.89 (1.36 - 2.64) for group 4 compared with the reference group of group 1 (P < 0.001 for trend). CONCLUSIONS: Serum uric acid was clearly associated with prevalence of hypertension in a general population of Japanese.

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