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1.
Thromb J ; 21(1): 84, 2023 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-37544993

RESUMEN

BACKGROUND: We compared the prognostic value of the Japanese Society on Thrombosis and Hemostasis (JSTH) disseminated intravascular coagulation (DIC) diagnostic criteria with that of the International Society on Thrombosis and Haemostasis (ISTH) DIC diagnostic criteria for 28-day in-hospital mortality. METHODS: We conducted a multicenter prospective cohort study involving two hematology departments, four emergency departments, and one general medicine department in Japan between August 2017 and July 2021. We assessed three ISTH DIC diagnostic criteria categories using low cutoff levels of D-dimer (low D-dimer), high cutoff levels of D-dimer (high D-dimer), and fibrinogen/fibrin degradation products (FDP) as fibrin-related markers. The main outcome was diagnosis-based category additive net reclassification index (NRI). RESULTS: A total of 222 patients were included: 82 with hematopoietic disorders, 86 with infections, and 54 with other diseases. The 28-day in-hospital mortality rate was 14% (n = 31). The DIC rates diagnosed by the JSTH, ISTH-low D-dimer, high D-dimer, and FDP DIC diagnosis were 52.7%, 47.3%, 42.8%, and 27.0%, respectively. The overall category additive NRI by JSTH DIC diagnosis vs. ISTH-low D-dimer, high D-dimer, and FDP DIC diagnosis were - 10 (95% confidence interval [CI]: -28 to 8, p = 0.282), - 7.8 (95% CI: -26 to 10, p = 0.401), and - 11 (95% CI: -26 to 3, p = 0.131), respectively. CONCLUSIONS: JSTH criterion showed the highest sensitivity for DIC diagnosis that did not improve but reflected the same prognostic value for mortality evaluated using ISTH DIC diagnosis criteria. This finding may help clinicians to use JSTH DIC criterion as an early intervention strategy in patients with coagulopathy.

2.
Thromb J ; 20(1): 33, 2022 Jun 13.
Artículo en Inglés | MEDLINE | ID: mdl-35698137

RESUMEN

BACKGROUND: We compared the prognostic value of serum high mobility group box 1 protein (HMGB1) and histone H3 levels with the International Society on Thrombosis and Haemostasis (ISTH) disseminated intravascular coagulation (DIC) scores for 28-day in-hospital mortality in patients with DIC caused by various underlying diseases. METHODS: We conducted a multicenter prospective cohort study including two hematology departments, four emergency departments, and one general medicine department in Japan, between August 2017 and July 2021. We included patients diagnosed with DIC by the ISTH DIC scoring system. RESULTS: Overall, 104 patients were included: 50 with hematopoietic disorders, 41 with infections, and 13 with the other diseases. The 28-day in-hospital mortality rate was 21%. The receiver operator characteristic (ROC) curve showed that a DIC score of 6 points, serum HMGB1 level of 8 ng/mL, and serum histone H3 level of 2 ng/mL were the optimal cutoff points. The odds ratios of more than these optimal cutoff points of the DIC score, serum HMGB1, and histone H3 levels were 1.58 (95% confidence interval [CI]: 0.60 to 4.17, p = 0.36), 5.47 (95% CI: 1.70 to 17.6, p = 0.004), and 9.07 (95% CI: 2.00 to 41.3, p = 0.004), respectively. The area under the ROC curve of HMGB1 (0.74, 95% CI: 0.63 to 0.85) was better than that of the ISTH DIC scores (0.55, 95% CI: 0.43 to 0.67, p = 0.03), whereas that of histone H3 was not (0.71, 95% CI: 0.60 to 0.82, p = 0.07). Calibration and net reclassification plots of HMGB1 identified some high-risk patients, whereas the ISTH DIC scores and histone H3 did not. The category-free net reclassification improvement of HMGB1 was 0.45 (95% CI: 0.01 to 0.90, p = 0.04) and that of histone H3 was 0.37 (95% CI: - 0.05 to 0.78, p = 0.08). CONCLUSIONS: Serum HMGB1 levels have a prognostic value for mortality in patients with DIC. This finding may help physicians develop treatment strategies.

3.
Transfus Apher Sci ; 59(3): 102737, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32051100

RESUMEN

Predictors of peripheral blood stem cell (PBSC) yield can potentially improve the comfort, safety, and efficacy of CD34+ cell collection from donors treated with recombinant human granulocyte colony-stimulating factor (G-CSF). We investigated 181 apheresis procedures on 109 healthy allogeneic donors to identify factors correlating with efficient PBSC collection. Apheresis started on Day 4 or 5 and continued up to Day 6 of G-CSF administration. CD34+ cell yields on Days 4 and 5 were comparable, and significantly higher than on Day 6. This suggests that starting apheresis on Day 4 rather than Day 5 may be preferable, to reduce G-CSF exposure and optimize yield, even if multi-day collection is required. More CD34+ cells were collected from male and cytomegalovirus (CMV)-seronegative donors than from female and CMV-seropositive donors, respectively. The yields of CD34+ cells were similarly high in both male and female donors aged 20-29 years; yields decreased in female donors in their thirties, and were comparably low in both male and female donors in their forties and thereafter. These findings should guide decision-making about when to begin apheresis, and encourage careful consideration of donor factors such as gender, age, and CMV serostatus when collecting PBSCs.


Asunto(s)
Eliminación de Componentes Sanguíneos/métodos , Factor Estimulante de Colonias de Granulocitos/inmunología , Células Madre de Sangre Periférica/inmunología , Adulto , Donantes de Sangre , Femenino , Humanos , Masculino , Adulto Joven
4.
Angew Chem Int Ed Engl ; 57(48): 15882-15886, 2018 Nov 26.
Artículo en Inglés | MEDLINE | ID: mdl-30324734

RESUMEN

Molecular topology of π-conjugated circuits becomes increasingly important in the chemistry of aromatic and antiaromatic compounds. meso-Pentafluorophenyl-substituted 5,35-(1,4-phenylene)bridged [56]dodecaphyrin was synthesized by condensation of 1,4-phenylene-bridged dicarbinol dimer and 5,10,15-tris-(pentafluorophenyl)tetrapyrrane followed by oxidation with DDQ and was oxidized to its [54]- and [52]congeners in a stepwise manner. Metalation of the [52]dodecaphyrin with Pd2 (dba)3 gave two bis-PdII complexes that are isomers of metalation sites: anti and syn with regard to the 1,4-phenylene bridge. The anti-isomer was easily oxidized to its N-fused form, a quadruply twisted non-aromatic or weakly aromatic macrocycle. On the other hand, the syn-isomer was revealed to be the first example of Hückel aromatic molecule with a quadruply twisted structure.

5.
J Am Chem Soc ; 139(34): 12050-12059, 2017 08 30.
Artículo en Inglés | MEDLINE | ID: mdl-28753299

RESUMEN

We have prepared a series of MII4L6 tetrahedral cages containing one or the other of two distinct BODIPY moieties, as well as mixed cages that contain both BODIPY chromophores. The photophysical properties of these cages and their fullerene-encapsulated adducts were studied in depth. Upon cage formation, the charge-transfer character exhibited by the bis(aminophenyl)-BODIPY subcomponents disappeared. Strong excitonic interactions were instead observed between at least two BODIPY chromophores along the edges of the cages, arising from the electronic delocalization through the metal centers. This excited-state delocalization contrasts with previously reported cages. All cages exhibited the same progression from an initial bright singlet state (species I) to a delocalized dark state (species II), driven by interactions between the transition dipoles of the ligands, and subsequently into geometrically relaxed species III. In the case of cages loaded with C60 or C70 fullerenes, ultrafast host-to-guest electron transfer was observed to compete with the excitonic interactions, short-circuiting the I → II → III sequence.

7.
Phys Chem Chem Phys ; 19(21): 13970-13977, 2017 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-28513708

RESUMEN

Herein, we revealed a symmetry-breaking charge transfer (SBCT) process in the excited state of a directly linked push-pull porphyrin dyad (AD) and triad (ADA) via spectroscopic measurements including steady-state absorption and fluorescence, time-resolved fluorescence (TRF), femtosecond transient absorption (fs-TA), and time-resolved infrared (TRIR) measurements. Unprecedented broad fluorescence spectra were observed for porphyrin arrays in polar solvents; these were attributed to the existence of a charge transfer state as evidenced by the TRF measurements. TA measurements also revealed emerging features of a CT state for AD and ADA in polar solvents. These dynamics were also confirmed via TRIR measurements, which provided further information on the solvation and structural relaxation processes of the SBCT process. This is the first observation of an SBCT process in porphyrin arrays, providing fundamental understanding of the strongly coupled porphyrin arrays. Thus, the results of this study reveal the potential of the porphyrin arrays in relevant applications requiring SBCT.

8.
Angew Chem Int Ed Engl ; 56(12): 3232-3236, 2017 03 13.
Artículo en Inglés | MEDLINE | ID: mdl-28252243

RESUMEN

Internally 1,3-phenylene- and 2,5-thienylene-bridged [46]decaphyrins 2 and 3 have been synthesized. While 2 shows modest aromatic character derived from the global 46π-conjugated circuit, 3 displays larger aromatic character owing to the contribution of an (annuleno)annulene-type network consisting of two twisted Möbius aromatic thia[28]hexaphyrin segments in addition to the global 46π-network. Upon protonation, these [46]decaphyrins underwent large structural changes to acquire strong aromaticity. Protonated 3 has been revealed to take on a planar structure composed of fused two triangular thia[28]hexaphyrin segments.

9.
Phys Chem Chem Phys ; 18(4): 3244-9, 2016 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-26742685

RESUMEN

The excited-state energy relaxation processes of a Zn(II)porphyrin­[26]hexaphyrin­Zn(II)porphyrin triply linked hybrid tape, FZn, have been investigated by femtosecond transient absorption spectroscopy (TA), using a directly meso­meso linked hybrid trimer, HZn, as a reference compound. FZn has a very small S1­S0 energy gap through the expansion of π-conjugation and the absorption band at 1897 nm corresponds to its lowest singlet excited-state as a consequence of enhanced transition dipole moment that lies parallel to the long molecular axis. In TA measurements, we observe an energy transfer process (0.4 ps) from the Zn(II)porphyrin moiety to the [26]hexaphyrin core in HZn. In contrast to HZn, a biexponential decay with the time constants of 0.25 and 6.5 ps was observed in the decay profile of FZn. The detailed analysis of excitation wavelength, temperature and solvent dependent TA in FZn revealed that the electronic relaxation process (0.25 ps) from S1 to S0 is faster than the vibrational relaxation processes (5.9 ps) in the excited and ground states due to a very small S1­S0 energy gap through the expansion of π-conjugation. Accordingly, we demonstrate that electronic deactivation overtakes vibrational relaxation processes in a highly conjugated FZn.

10.
J Am Chem Soc ; 137(37): 11856-9, 2015 Sep 23.
Artículo en Inglés | MEDLINE | ID: mdl-26340352

RESUMEN

We have demonstrated aromaticity reversal in the singlet excited states of internally 1,3-phenylene-strapped [26]- and [28]hexaphyrins (P26H and P28H). P26H displays a broad and reduced singlet-excited-state absorption spectrum, whereas P28H exhibits a sharp and intense singlet-excited-state absorption spectrum; both are in contrast to the ground-state absorption spectra, strongly indicating aromaticity reversal in the singlet excited state. Furthermore, magnetic and topological indices of aromaticity such as nucleus-independent chemical shift and harmonic oscillator model of aromaticity values for P26H and P28H also suggest that their singlet excited states become antiaromatic and aromatic, respectively.

11.
J Am Chem Soc ; 137(5): 2097-106, 2015 Feb 11.
Artículo en Inglés | MEDLINE | ID: mdl-25611358

RESUMEN

We describe the synthesis and characterization of directly meso-meso linked porphyrin-[26]hexaphyrin-porphyrin hybrid oligomers and their triply linked (completely fused) hybrid tapes. meso-meso Linked Ni(II) porphyrin-[26]hexaphyrin-Ni(II) porphyrin trimers were prepared by methanesulfonic acid-catalyzed cross-condensation of meso-formyl Ni(II) porphyrins with a 5,10-diaryltripyrrane followed by oxidation with 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ). The Ni(II) porphyrin moieties were converted to Zn(II) porphyrins via an indirect route involving reduction of the [26]hexaphyrin to its 28π congener, acid-induced denickelation, oxidation of the [28]hexaphyrin, and finally Zn(II) ion insertion. Over the course of these transformations, porphyrin-[28]hexaphyrin-porphyrin trimers have been revealed to take on a Möbius aromatic twisted structure for the [28]hexaphyrin segment. Oxidation of meso-meso linked hybrid trimer bearing 5,15-diaryl Zn(II) porphyrins with DDQ/Sc(OTf)3 under mild conditions resulted in meso-meso coupling oligomerization, affording the corresponding dimeric (hexamer), trimeric (nonamer), and tetrameric (dodecamer) oligomers. On the other hand, oxidation of a meso-meso linked hybrid trimer bearing 5,10,15-triaryl Zn(II) porphyrin terminals with DDQ/Sc(OTf)3 under harsher conditions afforded a meso-meso, ß-ß, ß-ß triply linked hybrid porphyrin tape, which displays a sharp and intense absorption band at 1912 nm. Comparison of this extremely red-shifted absorption band with those of Zn(II) porphyrin tapes suggests that the bathochromic-shifting capability of a [26]hexaphyrin unit is large, almost equivalent to that of four individual Zn(II) porphyrin units. As demonstrated, the fusion of porphyrins to [26]hexaphyrin offers an efficient means to expand their conjugation networks, significantly expanding the capabilities attainable for these chromophores.

12.
J Am Chem Soc ; 137(6): 2219-22, 2015 Feb 18.
Artículo en Inglés | MEDLINE | ID: mdl-25633052

RESUMEN

ß-to-ß Directly linked cyclic Ni(II) porphyrin trimer, tetramer, and pentamer ([3]CP, [4]CP, and [5]CP) have been synthesized by reaction of a 2,12-diborylated Ni(II) porphyrin with Pt(cod)Cl2 followed by reductive elimination. The structures of these cyclic porphyrin arrays have been revealed by X-ray diffraction analysis. The strain energies of these cyclic oligomers are calculated to be 77, 57, and 47 kcal/mol for [3]CP, [4]CP, and [5]CP, respectively. Intramolecular excitation energy hopping was observed between the (3)(d,d) states of the Ni(II) porphyrins with rates of 3.0, 4.4, and 4.6 ps for [3]CP, [4]CP, and [5]CP, respectively, reflecting the close proximity of the Ni(II) centers.

13.
Chemistry ; 21(19): 7007-11, 2015 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-25778944

RESUMEN

[26]Hexaphyrin(1.1.1.1.1.1) bearing two 5-formyl-2-pyrrolyl groups at the 5- and 20-positions was prepared by cross-condensation of 5,10-bis(pentafluorophenyl)-substituted tripyrrane with 2,5-diformylpyrrole as an effective binuclear metal-coordinating ligand, owing to the two hemiporphyrin-like NNNN pockets. In fact, metalation of this hexaphyrin with Zn(II) , Cu(II) , and Pd(II) salts proceed smoothly at room temperature to give the corresponding bismetal complexes that displayed remarkably redshifted absorption spectra reaching deep into near infrared region. These redshifted absorption bands are ascribed, through electrochemical investigations and DFT calculations, to two structural motifs: the N-metalopyrrole substructure that elevates the HOMO level due to the electron-donating property and the two coordinated metal ions that serve as Lewis acids to lower the LUMO level.

14.
Ann Hematol ; 99(2): 359-361, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31872359
15.
J Org Chem ; 80(23): 11726-33, 2015 Dec 04.
Artículo en Inglés | MEDLINE | ID: mdl-26218902

RESUMEN

5,20-Di(pyridin-2-yl)-[28]hexaphyrin(1.1.1.1.1.1) 7 was prepared and characterized as a stable Hückel antiaromatic molecule with a dumbbell-like structure stabilized by effective intramolecular hydrogen bonding interactions involving the 2-pyridyl nitrogen atoms. Pd(II) metalation of 7 afforded two bis-Pd(II) complexes, 9-syn and 9-anti, whose structures are rigidly held by Pd(II) coordination, rendering 9-syn to be nonaromatic because of its highly distorted structure and 9-anti to be Hückel antiaromatic because of its enforced planar dumbbell structure. In contrast, protonation of 7 with methanesulfonic acid (MSA) led to the formation of its triprotonated species 7H(3), which has been shown to take on twisted conformations with Möbius aromaticity in CH(2)Cl(2), while the structure was held to be a planar rectangular conformation in the crystal. Excited-state dynamics were measured for 7, 7H(3), 9-syn, and 9-anti, which indicated their electronic nature to be antiaromatic, aromatic, nonaromatic, and antiaromatic, respectively.

16.
Brain Cogn ; 100: 1-6, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26432377

RESUMEN

In humans, observation of others' behaviors increases corticospinal excitability (CSE), which is interpreted in the contexts of motor resonance and the "mirror neuron system" (MNS). It has been suggested that observation of another individual's behavior manifests an embodied simulation of his/her mental state through the MNS. Thus, the MNS may involve understanding others' intentions of behaviors, thoughts, and emotions (i.e., social cognition), and may therefore exhibit a greater response when observing human-interactive behaviors that require a more varied and complex understanding of others. In the present study, transcranial magnetic stimulation was applied to the primary motor cortex of participants observing human-interactive behaviors between two individuals (c.f. one person reaching toward an object in another person's hand) and non-interactive individual behavior (c.f. one person reaching toward an object on a dish). We carefully controlled the kinematics of behaviors in these two conditions to exclude potential effects of MNS activity changes associated with kinematic differences between visual stimuli. Notably, motor evoked potentials, that reflect CSE, from the first dorsal interosseous muscle exhibited greater amplitude when the participants observed interactive behaviors than when they observed non-interactive behavior. These results provide neurophysiological evidence that the MNS is activated to a greater degree during observation of human-interactive behaviors that contain additional information about the individuals' mental states, supporting the view that the MNS plays a critical role in social cognition in humans.


Asunto(s)
Potenciales Evocados Motores/fisiología , Neuronas Espejo/fisiología , Corteza Motora/fisiología , Tractos Piramidales/fisiología , Conducta Social , Adulto , Emociones , Mano/fisiología , Humanos , Masculino , Estimulación Magnética Transcraneal/métodos , Adulto Joven
17.
Angew Chem Int Ed Engl ; 54(50): 15197-201, 2015 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-26510641

RESUMEN

A set of 5,15-biphenylene-bridged porphyrin wheels, namely, [n]cyclo-5,15-porphyrinylene-4,4'-biphenylenes [n]CPB, have been synthesized through the platination of 5,15-bis(4-(pinacolboranyl)phenyl) nickel(II) porphyrin and subsequent reductive elimination of Pt(II) (cod)-bridged cyclic porphyrin intermediates. The calculated strain energies for [3]CPB, [4]CPB, [5]CPB, and [6]CPB are 49.3, 32.9, 23.5, and 16.0 kcal mol(-1) , respectively. UV/Vis absorption spectra and cyclic voltammetry indicated characteristic ring-size-dependent absorption-peak shifts and redox-potential shifts, which presumably reflect the degree of strain in the π-systems. Excitation-energy hopping (EEH) times were determined to be 5.1, 8.0, 8.0, and 9.6 ps for [3]CPB, [4]CPB, [5]CPB, and [6]CPB, respectively, in a pump-power-dependent TA experiment.

18.
Angew Chem Int Ed Engl ; 54(37): 10908-11, 2015 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-26197786

RESUMEN

A Zn(II) -Cu(I) -Zn(II) heterotrimetal complex of decaphyrin was synthesized by stepwise metalations: metalation of a [46]decaphyrin with Zn(II) ions to produce a 46π decaphyrin bis(Zn(II) ) complex and its subsequent metalation with Cu(II) ion. In the second metalation step, it has been shown that Cu(II) ion is reduced to a Cu(I) ion in the complex and a dianionic bis(Zn(II) ) containing [46]decaphyrin ligand is oxidized to the corresponding monoanionic [45]decaphyrin ligand, indicating a non-innocent nature of the decaphyrin ligand. Despite the radical nature, the heterotrimetal complex is fairly stable under ambient conditions and exhibits almost no intermolecular magnetic interaction, owing to extensive delocalization of an unpaired electron in the large π-conjugated circuit of decaphyrin moiety.

19.
Chemistry ; 20(32): 10065-72, 2014 Aug 04.
Artículo en Inglés | MEDLINE | ID: mdl-24976497

RESUMEN

A2 B-type B-methoxy subporphyrins 3 a-g and B-phenyl subporphyrins 7 a-c,e,g bearing meso-(2-substituted)aryl substituents are synthesized, and their rotational dynamics are examined through variable-temperature (VT) (1) H NMR spectroscopy. In these subporphyrins, the rotation of meso-aryl substituents is hindered by a rationally installed 2-substituent. The rotational barriers determined are considerably smaller than those reported previously for porphyrins. Comparison of the rotation activation parameters reveals a variable contribution of ΔH(≠) and ΔS(≠) in ΔG(≠). 2-Methyl and 2-ethyl groups of the meso-aryl substituents in subporphyrins 3 e, 3 f, and 7 e induce larger rotational barriers than 2-alkoxyl substituents. The rotational barriers of 3 g and 7 g are reduced by the presence of the 4-dibenzylamino group owing to its ability to stabilize the coplanar rotation transition state electronically. The smaller rotational barriers found for B-phenyl subporphyrins than for B-methoxy subporphyrins indicate a negligible contribution of SN 1-type heterolysis in the rotation of meso-aryl substituents.

20.
Chemistry ; 20(49): 16194-202, 2014 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-25336122

RESUMEN

meso-Bromosubporphyrin undergoes nucleophilic aromatic substitution (SN Ar) reactions with arylamines, diarylamines, phenols, ethanol, thiophenols, and n-butanethiol in the presence of suitable bases to provide the corresponding substitution products. The SN Ar reactions also proceed well with pyrrole, indole, and carbazole to provide substitution products in moderate to good yields. Finally, the SN Ar reaction with 2-bromothiophenol and subsequent intramolecular peripheral arylation reaction affords a thiopyrane-fused subporphyrin.

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