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Background: The superiority of anatomical liver resection (AR) for localized hepatocellular carcinoma (HCC) over nonanatomical liver resection (NR) remains controversial. This study aimed to investigate the impact of AR in preventing local and early HCC recurrence. Methods: A total of 280 patients who underwent initial liver resection for solitary HCC ≤5 cm in diameter were categorized into the AR and NR groups and compared using propensity score matching analysis. Results: Between the matched pairs (n = 87 in each group), the incidence rates of local and early (recurrence within 2 years after surgery) recurrences in the AR group were significantly lower than those in the NR group (13.8% vs. 28.7%, p =.025; 20.7% vs. 35.6%, p =.028, respectively). The overall survival in the AR group was better than that in the NR group (median: 13.4 vs. 7.6 years, p =.003). NR was among independent risk factors for early recurrence (odds ratio: 1.98, 95% CI: 1.1–3.6, p =.023) and prognostic factors for local recurrence (hazard ratio: 2.44, 95% CI: 1.4–4.4, p =.003). Conclusion: AR is superior in controlling local and early recurrence postoperatively for solitary HCC ≤5 cm in diameter compared with NR. [ABSTRACT FROM AUTHOR]

Colocutaneous fistula associated with Crohn's disease after mesh repair for inguinal hernia has not been previously reported in the literature. We report such case in an 83-year-old man following a preperitoneal repair of a left-sided inguinal hernia using Kugel patch. The patient has Crohn's disease in remission status for 4 years. One month after inguinal hernia repair, he presented with fever and left-sided inguinal pain and swelling. Computed tomography revealed abscess formation in the preperitoneal and subcutaneous space of the left-sided inguinal region. Colonoscopy showed local exacerbation of Crohn's disease in the sigmoid colon, and formation of fistula between the sigmoid colon and abdominal wall of the left-sided inguinal region. We performed mesh removal with Hartmann resection following percutaneous abscess drainage. The post-operative course was uneventful, and no sign of recurrence of the hernia was found for 3 years post-operatively. [ABSTRACT FROM AUTHOR]

The anharmonic vibrational frequencies of FHF- were computed by the vibrational self-consistent-field, configuration-interaction, and second-order perturbation methods with a multiresolution composite potential energy surface generated by the electronic coupled-cluster method with various basis sets. Anharmonic vibrational averaging was performed for the bond length and nuclear magnetic resonance indirect spin-spin coupling constants, where the latter computed by the equation-of-motion coupled-cluster method. The calculations placed the vibrational frequencies at 580 (ν1), 1292 (ν2), 1313 (ν3), 1837 (ν1+ν3), and 1864 cm-1 (ν1+ν2), the zero-point H–F bond length (r0) at 1.1539 Å, the zero-point one-bond spin-spin coupling constant [1J0(HF)] at 124 Hz, and the bond dissociation energy (D0) at 43.3 kcal/mol. They agreed excellently with the corresponding experimental values: ν1=583 cm-1, ν2=1286 cm-1, ν3=1331 cm-1, ν1+ν3=1849 cm-1, ν1+ν2=1858 cm-1, r0=1.1522 Å, 1J0(HF)=124±3 Hz, and D0=44.4±1.6 kcal/mol. The vibrationally averaged bond lengths matched closely the experimental values of five excited vibrational states, furnishing a highly dependable basis for correct band assignments. An adiabatic separation of high- (ν3) and low-frequency (ν1) stretching modes was examined and found to explain semiquantitatively the appearance of a ν1 progression on ν3. Our calculations predicted a value of 186 Hz for experimentally inaccessible 2J0(FF). [ABSTRACT FROM AUTHOR]

Redox active cofactors play a dynamic role inside protein binding active sites because the amino acids responsible for binding participate in electron transfer (ET) reactions. Here, we use femtosecond transient absorption (FsTA) spectroscopy to examine the ultrafast ET between quinacrine (Qc), an antimalarial drug with potential anticancer activity, and riboflavin binding protein (RfBP) with a known K d = 264 nM. Steady-state absorption reveals a ~ 10 nm red-shift in the ground state when QcH3 2+ is titrated with RfBP, and a Stern-Volmer analysis shows ~84% quenching and a blue-shift of the QcH3 2+ photoluminescence to form a 1:1 binding ratio of the QcH3 2+-RfBP complex. Upon selective photoexcitation of QcH3 2+ in the QcH3 2+-RfBP complex, we observe charge separation in 7 ps to form ¹[QcH3_red •+-RfBP•+], which persists for 138 ps. The FsTA spectra show the spectroscopic identification of QcH3_red • +, determined from spectroelectrochemical measurements in DMSO. We correlate our results to literature and report lifetimes that are 10-20× slower than the natural riboflavin, Rf-RfBP, complex and are oxygen independent. Driving force (ΔG) calculations, corrected for estimated dielectric constants for protein hydrophobic pockets, and Marcus theory depict a favorable one-electron ET process between QcH3 2+ and nearby redox active tyrosine (Tyr) or tryptophan (Trp) residues. [ABSTRACT FROM AUTHOR]

A hexylalkoxy dipolar D–A–A molecule [7-(4-N,N-(bis(4-hexyloxyphenyl)amino)phenyl)-2,1,3-(benzothia-diazol-4-yl)methylene]propane-dinitrile, (C6-TPA-BT-CN) has been synthesized and the photophysics studied via femtosecond transient absorption spectroscopy (FsTA) in toluene and in amorphous and liquid crystalline spherulite thin films. Two spherulite macromolecular crystalline phases (banded, and non-banded) were observed through concentration dependent, solution processing techniques and are birefringent with a negative sign of elongation. A dramatic change in the electronic absorption from blue in amorphous films to green in spherulites was observed, and the molecular orientation was determined through the combined analysis of polarized light microscopy, X-ray diffraction, and scanning electron microscopy. FsTA was performed on amorphous films and show complex charge recombination dynamics, and a Stark effect, characterized from the combined TPA+Ṗ and [BT-CN]−Ṗ spectroscopic signatures at 450 nm and 510 nm and identified through spectroelectrochemistry. Radical cation dynamics of TPA+Ṗ was observed selectively at 750 nm with ＞503.3 ps (18%) recombination kinetics resulting in a rather significant yield of free charge carriers in amorphous films and consistent with previous reports on energetically disordered blend films. However, photoexcitation on large, non-banded spherulites areas (＞250 μm) reveal average monoexponential charge recombination lifetimes of 169.2 ps from delocalized states similar to those observed in amorphous films and are 5× longer-lived than previous reports [Chang et al., J. Am. Chem. Soc., 2013, 135, 8790] of a related methyl-DPAT-BT-CN whose amorphous thin films were prepared through vapor deposition. Thus, the correlation between the microstructure of the blend film and the photoinduced radical pair dynamics described here is critical for developing a fundamental understanding of how dipolar states contribute to the charge carrier yield in a disordered energy system. [ABSTRACT FROM AUTHOR]

Multi-metallic complexes based on {Ru–Cr}, {Ru–Ru} and {Ru–Ru–Cr} fragments are investigated for their light-harvesting and long-range energy transfer properties. We report the synthesis and characterization of [Ru(tpy)(bpy)(μ-CN)Ru(py)4Cl]2+ and [Ru(tpy)(bpy)(μ-CN)Ru(py)4(μ-NC)Cr(CN)5]. The intercalation of {RuII(py)4} linked by cyanide bridges between {Ru(tpy)(bpy)} and {Cr(CN)5} results in efficient, distant energy transfer followed by emission from the Cr moiety. Characterization of the energy transfer process based on photophysical and ultrafast time-resolved absorption suggests the delocalization of holes in the excited state, providing a pathway for energy transfer between the end moieties. The proposed mechanism opens the door to utilize this family of complexes as an appealing platform for the design of antenna compounds as the properties of the fragments could be tuned independently. [ABSTRACT FROM AUTHOR]

A series of cyanide-bridged bimetallic compounds of the general formula [Ru(L)(bpy)(μ-NC)(M)]2−/−/2+ (L = tpy, 2,2′-6′,2′′-terpyridine, or tpm, tris(1-pyrazolyl)methane, bpy = 2,2′-bipyridine, M = RuII(CN)5, OsIII(CN)5, OsII(CN)5, RuII(py)4(CN), py = pyridine) have been synthesized and fully characterized. Most of them present MLCT emission (λ = 690–730 nm, Φ = 10−3–10−4) and their photophysical properties resemble the ones of the respective mononuclear Ru(L)(bpy) species. The exception is when M is OsIII(CN)5, where an intramolecular electron transfer quenching mechanism is proposed. The conditions that should be met for avoiding the reductive or oxidative quenching of the excited state are also discussed. [ABSTRACT FROM AUTHOR]

The anharmonic vibrational frequencies of FHF- were computed by the vibrational self-consistent-field, configuration-interaction, and second-order perturbation methods with a multiresolution composite potential energy surface generated by the electronic coupled-cluster method with various basis sets. Anharmonic vibrational averaging was performed for the bond length and nuclear magnetic resonance indirect spin-spin coupling constants, where the latter computed by the equation-of-motion coupled-cluster method. The calculations placed the vibrational frequencies at 580 (ν1), 1292 (ν2), 1313 (ν3), 1837 (ν1+ν3), and 1864 cm-1 (ν1+ν2), the zero-point H–F bond length (r0) at 1.1539 Å, the zero-point one-bond spin-spin coupling constant [1J0(HF)] at 124 Hz, and the bond dissociation energy (D0) at 43.3 kcal/mol. They agreed excellently with the corresponding experimental values: ν1=583 cm-1, ν2=1286 cm-1, ν3=1331 cm-1, ν1+ν3=1849 cm-1, ν1+ν2=1858 cm-1, r0=1.1522 Å, 1J0(HF)=124±3 Hz, and D0=44.4±1.6 kcal/mol. The vibrationally averaged bond lengths matched closely the experimental values of five excited vibrational states, furnishing a highly dependable basis for correct band assignments. An adiabatic separation of high- (ν3) and low-frequency (ν1) stretching modes was examined and found to explain semiquantitatively the appearance of a ν1 progression on ν3. Our calculations predicted a value of 186 Hz for experimentally inaccessible 2J0(FF). [ABSTRACT FROM AUTHOR]