10 research outputs found
Ferristatin II, an Iron Uptake Inhibitor, Exerts Neuroprotection against Traumatic Brain Injury via Suppressing Ferroptosis
As
a specific ferroptosis marker, transferrin receptor 1 (TfR1) expression is increased following
traumatic brain injury (TBI), but the precise role of TfR1 in TBI-induced
ferroptosis and neurodegeneration remains to be determined. To further
identify more potent ferroptosis inhibitors and effective targets
for treating TBI, our study aims at investigating the effects of TfR1
on ferroptosis in a mouse TBI model using ferristatin II (an iron
uptake and TfR1 inhibitor). The effect of ferristatin II was first
verified in the HT-22 cell line in vitro and showed
antiferroptotic action when exposed to ferric citrate (FAC), which
is in parallel with the results obtained from the positive controls,
including deferoxamine (DFO) and liproxstatin-1 (Lip-1). In
vivo, ferristatin II administration reduced the expression
of TfR1 at 12 h after TBI, and immunofluorescence experiments further
confirmed that this decreased TfR1-positive cells were neurons. Importantly,
ferristatin II suppressed TBI-induced iron homeostatic imbalance by
decreasing the content of Fe (III) and iron-positive deposits and
reversed the expression of iron homeostasis-related proteins. Moreover,
ferristatin II attenuated TBI-induced lipid peroxidation by reversing
the expression of lipid peroxidative genes and proteins, as well as
the increase in malondialdehyde (MDA) level following TBI. Finally,
ferristatin II alleviated TBI-induced neuronal injury and neurodegeneration,
as detected by staining with Nissl and Fluoro-Jade B, thereby exerting
a neuroprotective effect. In summary, these data indicated that ferristatin
II might be a potential strategy to restrain ferroptosis and develop
novel therapeutic agents against TBI
Unassisted Uranyl Photoreduction and Separation in a Donor–Acceptor Covalent Organic Framework
The
donor–acceptor covalent organic framework (COF) TTT–DTDA (TTT = thieno[3,2-b]thiophene-2,5-dicarbaldehyde
and DTDA = 4,4′,4″-(1,3,5-triazine-2,4,6-triyl)trianiline)
was prepared and found to have long-lived excited states (>100
ms)
characterized by transient absorption spectroscopy. These excited-state
lifetimes were sufficient to perform the direct photoreduction of
uranium at ppm concentration levels. The photoreduction of soluble
uranyl species to insoluble reduced uranium products is an attractive
separation for uranium, typically accomplished with sacrificial reagents
and protective gases. In the case of TTT–DTDA,
illumination in aqueous solutions containing only uranyl ions produced
crystalline uranyl peroxide species ([UO2(O2)]) at the COF that were characterized by powder X-ray diffraction,
X-ray photoelectron spectroscopy, and infrared spectroscopy. The maximum
absorption capacity of TTT–DTDA was found to be
123 mg U/g COF at pH 5 after 10 h of illumination in solutions devoid
of sacrificial reagents or protective gases. The TTT–DTDA COF was recyclable and maintained high selectivity for uranium in
competing ion experiments, which are necessary requirements for a
practical uranium extraction strategy based on photochemical uranium
reduction
Reversible Amine-to-Imine Chemistry at a Covalent Organic Framework for Sustainable Uranium Redox Separation
The
interconversion chemistry of amine-to-imine sites in a covalent
organic framework (COF) was developed for the redox-based separation
of uranium. Compared to traditional approaches using sacrificial reagents
or material decomposition for the reduction and separation of uranium,
amine-COF served as the electron donor and was regenerated repeatedly
following the oxidation and uranium reduction/separation. The amine-COF,
PI-3-AR, was formed from the sodium borohydride (NaBH4)
reduction of the imine-linked COF, PI-3, prepared from the solvothermal
synthesis of 1,3,5-triformyl benzene (TFB) and 4,4′,4″-(1,3,5-triazine-2,4,6-triyl)trianiline
(TTA). PI-3-AR could be converted back to PI-3 via oxidative amination
using an excess of the oxidant iodine, I2, or in the photochemical
reduction of uranyl ions (UO22+). In consecutive
photochemical uranium reduction and separation cycling experiments,
the reduced amine COF, PI-3-AR, underwent: (i) oxidation alongside
uranium photoreduction and deposition; (ii) acid treatment and uranium
extraction; and (iii) NaBH4 reduction and material recovery.
The COF, PI-3-AR, and novel separation process involving amine-to-imine
interconversion effectively removed uranium (maximum adsorption =
278 mg U/g COF) and maintained >98% uranium recovery over five
recycling
steps at pH 4.0
Data_Sheet_1_Cancer Related Subarachnoid Hemorrhage: A Multicenter Retrospective Study Using Propensity Score Matching Analysis.docx
ObjectiveTo investigate the clinical features, risk factors and underlying pathogenesis of cancer related subarachnoid hemorrhage (SAH).MethodsClinical data of SAH in patients with active cancer from January 2010 to December 2020 at four centers were retrospectively reviewed. Patients with active cancer without SAH were matched to SAH patients with active cancer group. Logistic regression was applied to investigate the independent risk factors of SAH in patients with active cancer, after a 1:1 propensity score matching (PSM). A receiver operator characteristic curve was configured to calculate the optimal cut-off value of the joint predictive factor for cancer related SAH.ResultsA total of 82 SAH patients with active cancer and 309 patients with active cancer alone were included. Most SAH patients with cancer had poor outcomes, with 30-day mortality of 41.5%, and with 90-day mortality of 52.0%. The PSM yielded 75 pairs of study participants. Logistic regression revealed that a decrease in platelet and prolonged prothrombin time were the independent risk factors of cancer related SAH. In addition, receiver operator characteristic curve of the joint predictive factor showed the largest AUC of 0.8131, with cut-off value equaling to 11.719, with a sensitivity of 65.3% and specificity of 89.3%.ConclusionPatients with cancer related SAH often have poor outcomes. The decrease in platelet and prolonged prothrombin time are the independent risk factors of cancer related SAH, and the joint predictive factor with cutoff value equal to 11.719 should hence serve as a novel biomarker of cancer related SAH.</p
Table_1_Cancer Related Subarachnoid Hemorrhage: A Multicenter Retrospective Study Using Propensity Score Matching Analysis.XLSX
ObjectiveTo investigate the clinical features, risk factors and underlying pathogenesis of cancer related subarachnoid hemorrhage (SAH).MethodsClinical data of SAH in patients with active cancer from January 2010 to December 2020 at four centers were retrospectively reviewed. Patients with active cancer without SAH were matched to SAH patients with active cancer group. Logistic regression was applied to investigate the independent risk factors of SAH in patients with active cancer, after a 1:1 propensity score matching (PSM). A receiver operator characteristic curve was configured to calculate the optimal cut-off value of the joint predictive factor for cancer related SAH.ResultsA total of 82 SAH patients with active cancer and 309 patients with active cancer alone were included. Most SAH patients with cancer had poor outcomes, with 30-day mortality of 41.5%, and with 90-day mortality of 52.0%. The PSM yielded 75 pairs of study participants. Logistic regression revealed that a decrease in platelet and prolonged prothrombin time were the independent risk factors of cancer related SAH. In addition, receiver operator characteristic curve of the joint predictive factor showed the largest AUC of 0.8131, with cut-off value equaling to 11.719, with a sensitivity of 65.3% and specificity of 89.3%.ConclusionPatients with cancer related SAH often have poor outcomes. The decrease in platelet and prolonged prothrombin time are the independent risk factors of cancer related SAH, and the joint predictive factor with cutoff value equal to 11.719 should hence serve as a novel biomarker of cancer related SAH.</p
Isotope Effect-Enabled Crystal Enlargement in Metal–Organic Frameworks
Synthesizing large metal–organic framework (MOF)
single
crystals has garnered significant research interest, although it is
hindered by the fast nucleation kinetics that gives rise to numerous
small nuclei. Given the different chemical origins inherent in various
types of MOFs, the development of a general approach to enhancing
their crystal sizes presents a formidable challenge. Here, we propose
a simple isotopic substitution strategy to promote size growth in
MOFs by inhibiting nucleation, resulting in a substantial increase
in the crystal volume ranging from 1.7- to 165-fold. Impressively,
the crystals prepared under optimized conditions by normal approaches
can be further enlarged by the isotope effect, yielding the largest
MOF single crystal (2.9 cm × 0.48 cm × 0.23 cm) among the
one-pot synthesis method. Detailed in situ characterizations
reveal that the isotope effect can retard crystallization kinetics,
establish a higher nucleation energy barrier, and consequently generate
fewer nuclei that eventually grow larger. Compared with the smaller
crystals, the isotope effect-enlarged crystal shows 33% improvement
in the X-ray dose rate detection limit. This work enriches the understanding
of the isotope effect on regulating the crystallization process and
provides inspiration for exploring potential applications of large
MOF single crystals
Isotope Effect-Enabled Crystal Enlargement in Metal–Organic Frameworks
Synthesizing large metal–organic framework (MOF)
single
crystals has garnered significant research interest, although it is
hindered by the fast nucleation kinetics that gives rise to numerous
small nuclei. Given the different chemical origins inherent in various
types of MOFs, the development of a general approach to enhancing
their crystal sizes presents a formidable challenge. Here, we propose
a simple isotopic substitution strategy to promote size growth in
MOFs by inhibiting nucleation, resulting in a substantial increase
in the crystal volume ranging from 1.7- to 165-fold. Impressively,
the crystals prepared under optimized conditions by normal approaches
can be further enlarged by the isotope effect, yielding the largest
MOF single crystal (2.9 cm × 0.48 cm × 0.23 cm) among the
one-pot synthesis method. Detailed in situ characterizations
reveal that the isotope effect can retard crystallization kinetics,
establish a higher nucleation energy barrier, and consequently generate
fewer nuclei that eventually grow larger. Compared with the smaller
crystals, the isotope effect-enlarged crystal shows 33% improvement
in the X-ray dose rate detection limit. This work enriches the understanding
of the isotope effect on regulating the crystallization process and
provides inspiration for exploring potential applications of large
MOF single crystals
Isotope Effect-Enabled Crystal Enlargement in Metal–Organic Frameworks
Synthesizing large metal–organic framework (MOF)
single
crystals has garnered significant research interest, although it is
hindered by the fast nucleation kinetics that gives rise to numerous
small nuclei. Given the different chemical origins inherent in various
types of MOFs, the development of a general approach to enhancing
their crystal sizes presents a formidable challenge. Here, we propose
a simple isotopic substitution strategy to promote size growth in
MOFs by inhibiting nucleation, resulting in a substantial increase
in the crystal volume ranging from 1.7- to 165-fold. Impressively,
the crystals prepared under optimized conditions by normal approaches
can be further enlarged by the isotope effect, yielding the largest
MOF single crystal (2.9 cm × 0.48 cm × 0.23 cm) among the
one-pot synthesis method. Detailed in situ characterizations
reveal that the isotope effect can retard crystallization kinetics,
establish a higher nucleation energy barrier, and consequently generate
fewer nuclei that eventually grow larger. Compared with the smaller
crystals, the isotope effect-enlarged crystal shows 33% improvement
in the X-ray dose rate detection limit. This work enriches the understanding
of the isotope effect on regulating the crystallization process and
provides inspiration for exploring potential applications of large
MOF single crystals
Isotope Effect-Enabled Crystal Enlargement in Metal–Organic Frameworks
Synthesizing large metal–organic framework (MOF)
single
crystals has garnered significant research interest, although it is
hindered by the fast nucleation kinetics that gives rise to numerous
small nuclei. Given the different chemical origins inherent in various
types of MOFs, the development of a general approach to enhancing
their crystal sizes presents a formidable challenge. Here, we propose
a simple isotopic substitution strategy to promote size growth in
MOFs by inhibiting nucleation, resulting in a substantial increase
in the crystal volume ranging from 1.7- to 165-fold. Impressively,
the crystals prepared under optimized conditions by normal approaches
can be further enlarged by the isotope effect, yielding the largest
MOF single crystal (2.9 cm × 0.48 cm × 0.23 cm) among the
one-pot synthesis method. Detailed in situ characterizations
reveal that the isotope effect can retard crystallization kinetics,
establish a higher nucleation energy barrier, and consequently generate
fewer nuclei that eventually grow larger. Compared with the smaller
crystals, the isotope effect-enlarged crystal shows 33% improvement
in the X-ray dose rate detection limit. This work enriches the understanding
of the isotope effect on regulating the crystallization process and
provides inspiration for exploring potential applications of large
MOF single crystals
Isotope Effect-Enabled Crystal Enlargement in Metal–Organic Frameworks
Synthesizing large metal–organic framework (MOF)
single
crystals has garnered significant research interest, although it is
hindered by the fast nucleation kinetics that gives rise to numerous
small nuclei. Given the different chemical origins inherent in various
types of MOFs, the development of a general approach to enhancing
their crystal sizes presents a formidable challenge. Here, we propose
a simple isotopic substitution strategy to promote size growth in
MOFs by inhibiting nucleation, resulting in a substantial increase
in the crystal volume ranging from 1.7- to 165-fold. Impressively,
the crystals prepared under optimized conditions by normal approaches
can be further enlarged by the isotope effect, yielding the largest
MOF single crystal (2.9 cm × 0.48 cm × 0.23 cm) among the
one-pot synthesis method. Detailed in situ characterizations
reveal that the isotope effect can retard crystallization kinetics,
establish a higher nucleation energy barrier, and consequently generate
fewer nuclei that eventually grow larger. Compared with the smaller
crystals, the isotope effect-enlarged crystal shows 33% improvement
in the X-ray dose rate detection limit. This work enriches the understanding
of the isotope effect on regulating the crystallization process and
provides inspiration for exploring potential applications of large
MOF single crystals
