Neutral Boryl Radicals in Mixed-Valent B(III) Br-B(II) Adducts.

The general strategies to stabilize a boryl radical involve single electron delocalization by π-system and the steric hinderance from bulky groups. Herein, a new class of boryl radicals is reported, with intramolecular mixed-valent B(III) Br-B(II) adducts ligated by a cyclic (alkyl)(amino)carbene (CAAC). The radicals feature a large spin density on the boron center, which is ascertained by EPR spectroscopy and DFT calculations. Structural and computational analyses revealed that the stability of radical species was assisted by the CAAC ligand and a weak but significant B(III)Br-B(II) interaction, suggesting a cooperative avenue for stabilization of boryl radicals. Two-electron reduction of these new boryl radicals provides C-H insertion products via a borylene intermediate.

Surgical treatment of bipolar segmental clavicle fracture: A case report.

BACKGROUND: Shoulder injuries caused by trauma are common, including clavicle fractures. Even so, bipolar segmental fracture of the clavicle is extremely rare and seldom reported. Therefore, there is still a controversial issue about how to treat these bipolar segmental clavicle fractures. CASE SUMMARY: A 56-year-old security guard arrived at our emergency room after falling on his electric bicycle. There was no loss of consciousness or other pain. He had no numbness in his fingers. X-rays and 3D computed tomography revealed that the patient's right shoulder had a bipolar segmental clavicle fracture. The surgical procedure included both open reduction and internal fixation. At the 1-year follow-up, he had a full range of motion and minimal discomfort in the injured shoulder. CONCLUSION: We provide a rare case of bipolar clavicle facture in the right clavicle. We hold the opinion that such patients would get better clinical and radiological outcomes by early and correct operation.

Difluorocarbene-derived trifluoromethylselenolation of benzyl halides.

Cu-Promoted difluorocarbene-derived trifluoromethylselenolation of benzyl halides with the Ph3P+CF2CO2-/Se/F- system is described. Three new carbon-heteroatom bonds, a Se-CF2 bond, SeCF2-F bond, and C-SeCF3 bond, were sequentially formed in the reaction. This work represents the first trifluoromethylselenolation protocol involving an external fluoride for the generation of the key intermediate, CF3Se- anion.

PALLD Regulates Phagocytosis by Enabling Timely Actin Polymerization and Depolymerization.

PALLD is an actin cross-linker supporting cellular mechanical tension. However, its involvement in the regulation of phagocytosis, a cellular activity essential for innate immunity and physiological tissue turnover, is unclear. We report that PALLD is highly induced along with all-trans-retinoic acid-induced maturation of myeloid leukemia cells, to promote Ig- or complement-opsonized phagocytosis. PALLD mechanistically facilitates phagocytic receptor clustering by regulating actin polymerization and c-Src dynamic activation during particle binding and early phagosome formation. PALLD is also required at the nascent phagosome to recruit phosphatase oculocerebrorenal syndrome of Lowe, which regulates phosphatidylinositol-4,5-bisphosphate hydrolysis and actin depolymerization to complete phagosome closure. Collectively, our results show a new function for PALLD as a crucial regulator of the early phase of phagocytosis by elaborating dynamic actin polymerization and depolymerization.

An Up-regulation of IRF-1 After a Spinal Cord Injury: Implications for Neuronal Apoptosis.

IRF-1, a kind of transcription factor, is expressed in many cell types, except in early embryonal cells. IRF-1 has played an essential role in various physiological and pathological processes, including tumor immune surveillance, viral infection, development of immunity system and pro-inflammatory injury. However, the expression and function of IRF-1 in spinal cord injury (SCI) are still unknown. In this study, we have performed an acute SCI model in adult rats and investigated the dynamic changes of IRF-1 expression in the spinal cord. Western blot have shown that IRF-1 protein levels gradually increased, reaching a peak at day 3 and then gradually declined to a normal level at day 14 after SCI. Double immunofluorescence staining showed that IRF-1 immunoreactivity was found in neurons, but not in astrocytes and microglia. Additionally, colocalization of IRF-1/active caspase-3 was detected in neurons. In vitro, IRF-1 depletion, by short interfering RNA, obviously decreases neuronal apoptosis. In conclusion, this is the first description of IRF-1 expression in spinal cord injury. Our results suggested that IRF-1 might play crucial roles in CNS pathophysiology after SCI.

[Effect of periostin on the function of human umbilical vein endothelial cells in acidic environment].

OBJECTIVE: To observe the effect of recombinant periostin protein on the proliferation, apoptosis and migration of human umbilical vein endothelial cells (HUVECs) in acidic environment. METHODS: HUVECs were divided into three groups: normal control (pH 7.31±0.03), acidic control (pH 6.95±0.05) and experimental groups [(periostin 100 µg/L, (pH 6.95±0.05)]. The cellular proliferation,apoptosis and migration were measured by Cell Counting Kit-8(CCK-8) assay, Annexin V-FITC with Flow Cytometer(at 60 h after periostin was given) and Transwell chamber assay (at 20 h after periostin was given). RESULTS: In CCK-8 assay, the optical density values D450 nm (at 72 h after periostin was given) of normal control, acidic control and experimental groups were 0.71± 0.05, 0.62±0.04, 0.69±0.02, respectively. In the same order, the total apoptotic rate (%) of the three groups were 13.06±1.35, 16.95±0.46, 12.97±1.60, respectively; the numbers of migrated cells of the three groups were 67.45±11.88,44.89±8.67,64.60±9.63, respectively. Compared with normal control, the D(450 nm) value and the number of migrated cells of acidic control reduced 12.68% (P<0.01) and 33.44% (P<0.01) respectively. Otherwise, the total apoptotic rate (%) increased by 29.79% (P<0.05). Compared with acidic control, the D(450 nm) value and the number of migrated cells of experimental group increased by 11.29% (P<0.01) and 43.90% (P<0.01), respectively. Meantime, the total apoptotic rate (%) reduced 23.48% (P<0.05). CONCLUSION: In acidic environment, the HUVECs' abilities of proliferation and migration were lower; while, the apoptotic value was raised. The recombinant periostin protein could counteract the acidic influence by enhancing the cellular abilities of proliferation and migration. Periostin could make endothelial cells reisist acidosis and keep growing to form blood vessels so that the local histiocytes could get enough nutrients for survival.

IFN-gamma and TNF-alpha inhibit expression of TGF-beta-1, its receptors TBETAR-I and TBETAR-II in the corpus luteum of PMSG/hCG treated rhesus monkey.

The corpus luteum (CL) is a transient endocrine organ that secretes progesterone to support early pregnancy. Using in situ hybridization, immunohistochemistry and computer imaging analysis, we have investigated the expression of transforming growth factor beta 1(TGF-beta 1) , its receptors, type I (TbetaR-I) and type II (TbetaR-II) as well as steroidogenic acute regulatory protein (StAR) in the corpus luteum (CL) of the rhesus monkey at various stages of CL development. The CL was induced by injection of pregnant mare serum gonadotropin (PMSG)/human chorionic gonadotropin (hCG). The expression of TGF-beta 1, TbetaR-I and TbetaR-II as well as StAR was detected in the CL in a time-dependent manner, reaching the maximum levels on D10 (functional stage), and decreased on Day 18 (regression stage). Injection of interferon-gamma (IFN-gamma) or tumor necrosis factor-alpha (TNF-alpha) at the functional stage of CL development significantly decreased the expression of StAR, as well as TGF-beta 1, and its receptors TbetaR-I and TbetaR-II. Our results suggest that TGF-beta 1 and its receptors may play an important regulatory role in maintaining CL function, and that IFN-gamma or TNF-alpha is capable of inhibiting their expression in the CL.

Involvement of molecules related to angiogenesis, proteolysis and apoptosis in implantation in rhesus monkey and mouse.

We have established the well-defined cycling, pseudo-pregnant and pregnant rhesus monkey models, and used these to analyze expression of the common molecules specifically related to angiogenesis, apoptosis or proteolysis, such as vascular endothelial growth factor (VEGF) and its receptors KDR, flt-1, flt-4 and flk-1, basic fibroblast growth factor (bFGF) and its receptors Flg, transforming growth factor-alpha and beta1 (TGF-a/beta1), and TGF-beta1 receptor type I (TbetaR-I) and type II (TbetaR-II), as well as steroidogenic acute regulatory protein (StAR), tissue type plasminogen activator/urokinase plasminogen activator/plasminogen activator inhibitor type 1 (tPA/uPA/PAI-1) and matrix matalloproteinase type 1, -3/tissue inhibitor matalloproteinase type 1, -2, -3 (MMP-1, -3/TIMP-1, -2, -3), Fas/FasL, BcL-2/Bax, in the corpus luteum (CL), in the functional layer of the endometrium and in the materno-fetal boundary of the implantation site. We have demonstrated that: expression of these molecules in the monkey CL, endometrium and materno-fetal boundary of the implantation site is correlated well with CL functional and vascular development and with the processes involved in the establishment of the implantation window as well as with the early stages of placentation. A coordinated increase in tPA and its inhibitor PAI-1 expression in the monkey and rat CL may be instrumental in initiating luteal regression in both species, and correlated well with the timing of the closure of the implantation window, whereas high uPA activity in the CL is important for the early formation of the CL and for maintaining its function which is closely correlated to the period of establishment of the implantation window. Apoptosis, proteolysis and angiogenesis occur in the CL and in the endometrium during the time of establishment of the implantation window, as well as in the materno-fetal boundary of the implantation site at the early stages of placentation. It seems that these processes occur in these tissues in a coordinated and time- and cell-dependent manner, and are reliant on each other. Based on these observations, we have designed experiments to test the actions of some related available compounds on mouse implantation, used alone or in combination. The preliminary data showed that the compounds which could effectively affect apoptosis, angiogenesis or proteolysis in the implantation site were capable of effectively inhibiting implantation by acting on the endometrium and/or on the CL. Furthermore, the combined use of these compounds produced an obvious additive effect on inhibiting implantation. This finding suggested this may be a good approach for developing an anti-implantation agent.

VEGF, bFGF, and their receptors in the endometrium of rhesus monkey during menstrual cycle and early pregnancy.

A number of cytokines and growth factors are known to modulate proliferation and differentiation of human endometrium. In this study, the expression of vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF), and VEGF receptors, fms-like tyrosine kinase (Flt1) and kinase insert domain-containing region (KDR), and bFGF receptor 1 (Flg) were examined in the endometrium of rhesus monkey on Day 5, 10, 16, 20, 25 of menstrual cycle and on Day 19 of early pregnancy. Western blot analysis showed the specificity of the anti-human antibodies with the monkey tissue. The expression of mRNA and protein of VEGF was correlated with that of its receptor KDR, which was detected in epithelial, vascular, and myometrial cells. The localization of bFGF and its receptor Flg was similar to that of VEGF, except that the Flg was absent in the endothelial cells. Strong expression of VEGF and bFGF in the glandular epithelial cells was observed in the proliferative phase, declined in the secretory phase during the cycle. Stronger staining of these factors was also observed in the decidual cells of the pregnant uterus, as compared with the stromal cells of cycling uterus. No expression of Flt1 was detected in the tissue examined in this study. These data suggest that VEGF, bFGF, and their receptors play important roles in epithelial and stromal development, angiogenesis, and blood vessel function in the endometrium during the menstrual cycle and early pregnancy of the rhesus monkey.

Regulatory effect of IFN-gamma on expression of TGF-beta 1, T beta R-II, and StAR in corpus luteum of pregnant rhesus monkey.

AIM: To examine expression of transforming growth factor-beta 1 (TGF-beta 1) and TGF beta receptor II (T beta R-II) and steroidogenic acute regulatory protein (StAR) in the corpus luteum (CL) of pregnant monkeys at various stages and to study possible effect of IFN-gamma on their production. METHODS: In situ hybridization and immunohistochemistry were applied to detect mRNA and protein. RESULTS: The expression of StAR, TGF-beta 1, and T beta R-II in the pregnant monkey CL was progressively decreased from d 15 to d 35 of gestation. IFN-gamma down-regulated the expression of TGF-beta 1, T beta R-II, as well as StAR. CONCLUSION: TGF-beta 1 may play an important role in the CL formation and functional maintaining; IFN-gamma down-regulates the expression of TGF-beta 1, T beta R-II, and StAR.