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1.
Stem Cells ; 42(5): 430-444, 2024 May 15.
Article in English | MEDLINE | ID: mdl-38253331

ABSTRACT

It has been documented that the uterus plays a key cardio-protective role in pre-menopausal women, which is supported by uterine cell therapy, to preserve cardiac functioning post-myocardial infarction, being effective among females. However, whether such therapies would also be beneficial among males is still largely unknown. In this study, we aimed to fill in this gap in knowledge by examining the effects of transplanted uterine cells on infarcted male hearts. We identified, based on major histocompatibility complex class I (MHC-I) expression levels, 3 uterine reparative cell populations: MHC-I(neg), MHC-I(mix), and MHC-I(pos). In vitro, MHC-I(neg) cells showed higher levels of pro-angiogenic, pro-survival, and anti-inflammatory factors, compared to MHC-I(mix) and MHC-I(pos). Furthermore, when cocultured with allogeneic mixed leukocytes, MHC-I(neg) had lower cytotoxicity and leukocyte proliferation. In particular, CD8+ cytotoxic T cells significantly decreased, while CD4+CD25+ Tregs and CD4-CD8- double-negative T cells significantly increased when cocultured with MHC-I(neg), compared to MHC-I(mix) and MHC-I(pos) cocultures. In vivo, MHC-I(neg) as well as MHC-I(mix) were found under both syngeneic and allogeneic transplantation in infarcted male hearts, to significantly improve cardiac function and reduce the scar size, via promoting angiogenesis in the infarcted area. All of these findings thus support the view that males could also benefit from the cardio-protective effects observed among females, via cell therapy approaches involving the transplantation of immuno-privileged uterine reparative cells in infarcted hearts.


Subject(s)
Myocardial Infarction , Uterus , Myocardial Infarction/therapy , Myocardial Infarction/pathology , Male , Female , Animals , Uterus/blood supply , Mice , Mice, Inbred C57BL , Histocompatibility Antigens Class I/metabolism
2.
Blood ; 140(16): 1790-1802, 2022 10 20.
Article in English | MEDLINE | ID: mdl-35981465

ABSTRACT

The bispecific T-cell engager (BiTE) blinatumomab against CD19 and CD3 has emerged as the most successful bispecific antibody (bsAb) to date; however, a significant proportion of patients do not respond to the treatments or eventually experience relapse after an initial response, and the recurrence rate increases significantly due to escape or downregulation of the CD19 antigen. To enhance antitumor efficacy and overcome potential immune escape, we developed a novel approach to design a CD19/CD22/CD3 trispecific antibody (tsAb) by site-specifically fusing anti-CD19 scFv (FMC63) and anti-CD22 nanobody (Nb25) to the defined sites of the CD3 antigen-binding fragment (Fab, SP34). This strategy allows for the optimal formation of immune synapses mediated by CD19/CD22/CD3 between target cells and T cells. Optimized tsAb can be superior for inducing T-cell-specific cytotoxicity and cytokine production against CD19+ and/or CD22+ tumor cells compared to other tsAb formats, and demonstrated significantly enhanced antitumor efficacy and the ability to overcome immune escape compared with the corresponding bsAbs alone or in combination, as well as with blinatumomab. In addition, tsAb treatment can lead to the long-term elimination of primary B-ALL patient samples in the PDX model and significantly prolong survival. This novel approach provides unique insight into the structural optimization of T-cell-redirected multispecific antibodies using site-specific recombination, and may be broadly applicable to heterogeneous and resistant tumor populations as well as solid tumors.


Subject(s)
Antibodies, Bispecific , Burkitt Lymphoma , Lymphoma, B-Cell , Precursor Cell Lymphoblastic Leukemia-Lymphoma , Humans , Antigens, CD19 , CD3 Complex , Neoplasm Recurrence, Local/drug therapy , Antibodies, Bispecific/pharmacology , Antibodies, Bispecific/therapeutic use , Lymphoma, B-Cell/pathology , Precursor Cell Lymphoblastic Leukemia-Lymphoma/drug therapy , Burkitt Lymphoma/drug therapy , Cytokines , Sialic Acid Binding Ig-like Lectin 2
3.
Opt Express ; 32(10): 17942-17952, 2024 May 06.
Article in English | MEDLINE | ID: mdl-38858962

ABSTRACT

The interaction between the intrinsic polarity of the host material and the TADF guest material affects charge injection and transport, exciton formation, charge recombination, and emission mechanisms. Therefore, understanding and controlling the interaction between the intrinsic polarity of the host material and the TADF guest material is very important to realize efficient TADF-OLED devices. This study investigated the molecular interaction between different polar host materials and a thermally activated delayed fluorescence material (DMAc-PPM). It has been found that interaction between the host and guest (π-π stacking interaction, multiple CH/π contacts) greatly influence the molecular transition dipole moment orientation of the guest. And the OLED devices based on the strong polar host (DPEPO) exhibited the highest EQEmax and lowest luminescence intensity, while devices using the weaker polar hosts mCP and CBP achieved higher luminance and lower EQEmax. Then, the strong polar host DPEPO was mixed with the weaker polar hosts CBP and mCP, respectively. The devices prepared based on the mixed-host DPEPO: mCP showed a 2.2 times improvement in EQEmax from 6.3% to 20.1% compared to the single-host mCP. The devices prepared based on the mixed-host DPEPO: CBP showed a 3.1 times improvement in luminance intensity from 1023 cd/m2 to 4236 cd/m2 compared to the single host of DPEPO. This suggests that optimizing the polarity of host materials has the potential to enhance the performance of solution prepared OLED devices.

4.
Angew Chem Int Ed Engl ; 63(45): e202411588, 2024 Nov 04.
Article in English | MEDLINE | ID: mdl-39054700

ABSTRACT

Organic ultralong room temperature phosphorescence (OURTP) materials capable of combining various emission behaviors for diversified optoelectronic properties and applications have recently gained a vigorous development, but it remains a forbidden challenge in designing OURTP molecules with hybrid local and charge-transfer (HLCT) feature, possibly due to the elevated difficulties in simultaneously meeting the stringent requirements of both HLCT and OURTP emitters. Here, through introducing multiple heteroatoms into one-dimensional fused ring of coumarin with moderate charge transfer perturbation in donor-π-acceptor architecture, we demonstrate a HLCT-featured OURTP molecule showing both promoted fluorescence with a quantum yield of 77 % in solution and long-lived OURTP with a lifetime of 251 ms in conventional host material used in electroluminescent device. Thus, efficient OURTP organic light-emitting diodes (OLEDs) were fabricated, exhibiting bright electroluminescence with an exciton utilization efficiency of 85 % and yellow OURTP lasting over 2 s for afterglow. Impressively, the HLCT OURTP-OLEDs can be further optimized to reach an unprecedented total external quantum efficiency (EQE) of ~12 % and OURTP EQE up to 3.11 %, representing the highest performance among the reported OURTP-OLEDs. These impressive results highlight the significance to fuse HLCT and OURTP together in enriching OURTP materials and improving the afterglow OLED performances.

5.
Stem Cells ; 40(6): 564-576, 2022 06 22.
Article in English | MEDLINE | ID: mdl-35291015

ABSTRACT

AIMS: To date, stroke remains one of the leading causes of death and disability worldwide. Nearly three-quarters of all strokes occur in the elderly (>65 years old), and a vast majority of these individuals develop debilitating cognitive impairments that can later progress into dementia. Currently, there are no therapies capable of reversing the cognitive complications which arise following a stroke. Instead, current treatment options focus on preventing secondary injuries, as opposed to improving functional recovery. METHODS: We reconstituted aged (20-month old) mice with Sca-1+ bone marrow (BM) hematopoietic stem cells isolated from aged or young (2-month old) EGFP+ donor mice. Three months later the chimeric aged mice underwent cerebral ischemia/reperfusion by bilateral common carotid artery occlusion (BCCAO), after which cognitive function was evaluated. Immunohistochemical analysis was performed to evaluate host and recipient cells in the brain following BCCAO. RESULTS: Young Sca-1+ cells migrate to the aged brain and give rise to beneficial microglial-like cells that ameliorate stroke-induced loss of cognitive function on tasks targeting the hippocampus and cerebellum. We also found that young Sca-1+ cell-derived microglial-like cells possess neuroprotective properties as they do not undergo microgliosis upon migrating to the ischemic hippocampus, whereas the cells originating from old Sca-1+ cells proliferate extensively and skew toward a pro-inflammatory phenotype following injury. CONCLUSIONS: This study provides a proof-of-principle demonstrating that young BM Sca-1+ cells play a pivotal role in reversing stroke-induced cognitive impairments and protect the aged brain against secondary injury by attenuating the host cell response to injury.


Subject(s)
Brain Ischemia , Stroke , Animals , Bone Marrow Cells , Brain Ischemia/complications , Hippocampus , Mice , Stem Cells , Stroke/complications
6.
J Environ Manage ; 325(Pt B): 116626, 2023 Jan 01.
Article in English | MEDLINE | ID: mdl-36327606

ABSTRACT

As a major intermediate metabolite of synthetic pyrethroids, the occurrence of 3-phenoxybenzoic acid hinders the decomposition of the parent pesticide and poses uncertain risks to environmental ecology and living organisms. Strain Aspergillus oryzae M-4 was previously reported to degrade 3-PBA and several substances were identified as downstream transformation products (TPs). But the mechanism underlying the cleavage of ether bond remains largely unclear. Here, we attempted to address such concern through identifying the peripheral TPs and analyzing transcriptomics, coupled with serial batch degradation experiments. Analysis results of chromatographic/mass spectrometry suggested that 3-PBA underwent twice hydroxylation, to yield mono- and dihydroxylated 3-PBA successively. In parallel, a mutual transformation between 3-PBA and 3-phenoxybenzyl alcohol (3-PBOH) also existed. The proposal of peripheral pathway represents an important advance towards fully understanding the whole 3-PBA metabolism in M-4. A specific altered metabolization was found for the first time, that is, resting cells of M-4 skipped the reduction step and initiate hydroxylation directly, by comparison with growing cells. Transcriptome analysis indicated that 3-PBA induced the up-regulation of genes related to energy investment, oxidative stress response, membrane transport and DNA repair. In-depth functional interpretation of differential expression genes suggested that the generation 3-PBOH and hydroxylated 3-PBA may be due to the participation of flavin-dependent monooxygenases (FMOs) and cytochrome P450 (CYP450), respectively. This study provides new insight to reveal the biodegradation mechanism of 3-PBA by A. oryzae M-4.


Subject(s)
Aspergillus oryzae , Pyrethrins , Aspergillus oryzae/genetics , Aspergillus oryzae/metabolism , Transcriptome , Gene Expression Profiling
7.
Opt Express ; 30(14): 25865-25875, 2022 Jul 04.
Article in English | MEDLINE | ID: mdl-36237107

ABSTRACT

The organic semiconductor lasers (OSLs) have been seen as a promising light source for future applications. Achieving organic semiconductors with low amplified spontaneous emission (ASE) threshold is a key progress toward the electrically pumped OSLs. In this paper, the ASE properties of CBP: 2wt% BUBD-1 blend films were optimized using buffer layers containing silver nanoparticles (Ag NPs) with different ratios. Both photoluminescence intensity and ASE properties of blend films were optimized when the buffer layer with 25 vol% Ag NPs was introduced. The lowest ASE threshold is 0.47 µJ/Pulse (6.71 µJ/cm2), which reduces 67.6%, and the highest gain factor is 20.14 cm-1, which enhances 47.8% compared with that without buffer layers. The enhancement of ASE properties of blend films was ascribed to the four functions of the Ag NPs doped buffer layers, including the low refractive index of PMMA and the triple localized surface plasmon resonance (LSPR) effects of Ag NPs in buffer layers. The results show that the buffer layer modified by metal nanoparticles has great application potential in improving the lasing performance of organic small molecules.

8.
Opt Express ; 30(24): 43281-43292, 2022 Nov 21.
Article in English | MEDLINE | ID: mdl-36523029

ABSTRACT

With the development of surface enhanced fluorescence (SEF) spectroscopy technology, uniform and low-cost SEF substrate is urgently needed. In this paper, the nanocomposite films of poly (vinyl alcohol) (PVA) embedded with in-situ Au particles, their localized surface plasmon resonance (LSPR) bands locate at different wavelengths from 525 nm to 569 nm, were used as substrates to enhance the fluorescence of rhodamine 6 G (R6G). The results shows that the uniform light emission in large area can be measured, and the maximum enhancement factor (EF) is about 13 folds. With increasing concentration of R6G films, the EF first increases and then slowly decreases. It is demonstrated that the EF greatly depends on the matching degree of the emission/excitation of R6G and the LSPR band of PVA-Au substrate. All the results further suggests that the PVA-Au substrate not only realize the fluorescence enhancement but also attenuates the fluorescence quenching at higher concentration. In addition, the local electric distribution of the substrate is simulated by using three-dimensional finite different time-domain (FDTD) to further demonstrate the mechanism of the SEF. This substrate has good development prospects in the fields of fluorescent probes and fluorescence imaging, which can be beneficial to the development of uniform and low-cost SEF substrate.

9.
Langmuir ; 38(32): 9928-9939, 2022 08 16.
Article in English | MEDLINE | ID: mdl-35925777

ABSTRACT

Currently, the excessive application of fertilizers and the random discharge of waste water, waste gas, and residues have led to more and more serious soil pollution problems. Zeolite is the most promising material for preparing a green and environmentally friendly soil conditioner. Herein, the carbon nanotubes/polydopamine/ZSM-5 composite soil conditioner was prepared by a facile two-step method, and it was used to release fulvic acid and adsorb methylene blue to improve the environment. The cumulative release rate of the composite soil conditioner was 52% within 430 h for fulvic acid, which had a good sustained release effect and could be sustained-released in different acid-based surroundings. In addition, it showed a good adsorption capacity of methylene blue, and it is about 80.02 mg/g which was about six times higher than that of ZSM-5. It was beneficial for the adsorption of methylene blue in a neutral environment. Finally, it could promote the growth of brassica chinensis and maize, and the promotion effect was 60 and 35%, respectively. Therefore, the carbon nanotubes/polydopamine/ZSM-5 composite soil conditioner is a green and efficient material, which provides a new strategy to solve the problem of soil pollution.


Subject(s)
Nanotubes, Carbon , Adsorption , Delayed-Action Preparations , Indoles , Methylene Blue/chemistry , Polymers , Soil/chemistry
10.
Langmuir ; 38(18): 5717-5729, 2022 05 10.
Article in English | MEDLINE | ID: mdl-35442693

ABSTRACT

A multifunctional microspheric soil conditioner based on chitosan-grafted poly(acrylamide-co-acrylic acid)/biochar [CS-g-P(AM-co-AA)/BC] was prepared. First, the P(AM-co-AA) was synthesized and successfully grafted onto CS, and the three-dimensional network structure of microspheres was formed with N,N-methylenebis(acrylamide) as the cross-linking agent according to the inverse suspension polymerization method. Meanwhile, BC and urea were encapsulated into the body of microspheres during the polymerization. The structure of the microspheres was analyzed by Fourier transform infrared spectroscopy, polarized optical microscopy, and scanning electron microscopy, and the mechanism of adsorption of Cu2+ on the microspheres was investigated by X-ray photoelectron spectroscopy. Furthermore, the experimental results demonstrated the excellent water absorption and retention capabilities of microspheres, and the release rate of urea was dramatically reduced. Importantly, the introduction of BC significantly enhanced the adsorption performance of the microspheres with respect to heavy metal ions. Consequently, the multifunctional soil conditioner held promise for use in soil improvement and agricultural production.


Subject(s)
Chitosan , Acrylamides/chemistry , Adsorption , Charcoal , Chitosan/chemistry , Hydrogen-Ion Concentration , Microscopy, Electron, Scanning , Microspheres , Soil/chemistry , Spectroscopy, Fourier Transform Infrared , Urea
11.
Langmuir ; 38(28): 8585-8594, 2022 07 19.
Article in English | MEDLINE | ID: mdl-35793566

ABSTRACT

The water body environment is related to ecological and human health. Adsorption is an effective means to remove pollutants from water bodies. Currently, the common adsorbents suffer from disadvantages such as structural instability and poor adsorption performance under acidic conditions, which not only affect the adsorption efficiency but also cause secondary pollution of water bodies. In this study, a novel aminated multiwalled carbon nanotube-doped flower-like nanocomposite was designed, where the anionic or neutral groups were protonated under acidic conditions, and it displayed a higher adsorption capacity for dyes by ion exchange, represented by methylene blue (MB) and rhodamine B (RB). WSe2 in the composite increases its adsorption sites. The adsorption efficiency of pollutants in acidic wastewater was enhanced while avoiding secondary contamination. The synthesized composites showed maximum adsorptions of 27.55 and 27.47 mg/g for MB and RB, respectively. The current work offers a novel approach to treating acidic wastewater.


Subject(s)
Nanotubes, Carbon , Water Pollutants, Chemical , Adsorption , Coloring Agents/chemistry , Humans , Kinetics , Magnetic Phenomena , Methylene Blue/chemistry , Nanotubes, Carbon/chemistry , Wastewater , Water , Water Pollutants, Chemical/analysis
12.
Proc Natl Acad Sci U S A ; 116(32): 15889-15894, 2019 08 06.
Article in English | MEDLINE | ID: mdl-31332018

ABSTRACT

To direct checkpoint inhibition to the tumor microenvironment, while avoiding systemic immune activation, we have synthesized a bispecific antibody [norleucine4, d-Phe7]-melanocyte stimulating hormone (NDP-MSH)-antiprogrammed cell death-ligand 1 antibody (αPD-L1) by conjugating a melanocyte stimulating hormone (α-MSH) analog to the antiprogrammed cell death-ligand 1 to (αPD-L1) antibody avelumab. This bispecific antibody can bind to both the melanocortin-1 receptor (MC1R) and to PD-L1 expressed on melanoma cells and shows enhanced specific antitumor efficacy in a syngeneic B16-SIY melanoma mouse model compared with the parental antibody at a 5 mg/kg dose. Moreover, the bispecific antibody showed increased infiltrated T cells in the tumor microenvironment. These results suggest that a tumor-targeted PD-L1-blocking bispecific antibody could have a therapeutic advantage in vivo, especially when used in combination with other checkpoint inhibitors.


Subject(s)
Immunotherapy , Neoplasms/immunology , Neoplasms/therapy , Animals , HEK293 Cells , Humans , Melanoma, Experimental/pathology , Mice , Peptides/chemistry , alpha-MSH/analogs & derivatives , alpha-MSH/chemistry
13.
Opt Express ; 29(11): 16845-16856, 2021 May 24.
Article in English | MEDLINE | ID: mdl-34154237

ABSTRACT

The transition dipole moment (TDM) orientation in the emission layer (EML) of organic light-emitting diodes (OLEDs) have attracted increasing attention from many researchers. But the study point at the molecular orientation in the hole transport layer (HTL) and electron transport layer (ETL) was not reported widely. In this paper, the molecular orientation of HTLs and ETLs were controlled by the deposition rate. The angle-dependent PL spectra and the variable angle spectroscopic ellipsometry (VASE) were used for evaluating the molecular orientation of B3PYMPM and TAPC, respectively. We found that fast deposition rate can boost preferentially vertical molecular orientation in both molecules and facilitate the hole and electron mobility, which was tested by the current density-voltage and capacitance-voltage curves of HODs and EODs. Moreover, the HTLs and ETLs were employed in OLED devices to verify the influence of molecular orientation on charge carrier mobility, which determined the performance of OLEDs significantly.

14.
Scand J Gastroenterol ; 56(5): 570-577, 2021 May.
Article in English | MEDLINE | ID: mdl-33792461

ABSTRACT

BACKGROUND: Prolonged corrected QT (QTc) interval is a hallmark of cirrhotic cardiomyopathy (CCM) and has been ascertained to predict mortality in cirrhosis. However, some critical issues remain to be addressed including unanimous cut-off, calculation approach and applicable population. METHODS: A total of 274 patients with cirrhosis were included. The prolonged QTc interval over 440 ms according to adjusted Fridericia's formula was used to stratify enrolled subjects. Independent predictors of 3-year mortality were identified with Cox regression model. The Kaplan-Meier method was implemented to obtain survival curves. To reduce impact of selection bias and possible confounders, a propensity score matching (PSM) analysis was used. RESULTS: QTc > 440 ms was an independent risk factor in the entire cohort and PSM subset (HR 2.532, 95% CI 1.431-4.480, p=.001; HR 2.802, 95% CI 1.171-6.701, p=.021, respectively). Subgroup analysis showed that QTc > 440 ms was an independent predictor in cirrhotics with age ≤60 years (HR = 1.02, p=.035) and in the presence of ascites (HR = 1.01, p=.008). CONCLUSIONS: The prolonged QTc interval might help to identify patients with high-risk of all-cause mortality.


Subject(s)
Electrocardiography , Long QT Syndrome , Heart Rate , Humans , Infant, Newborn , Liver Cirrhosis/complications , Propensity Score , Risk Factors
15.
BMC Womens Health ; 21(1): 90, 2021 03 02.
Article in English | MEDLINE | ID: mdl-33653321

ABSTRACT

BACKGROUND: Inguinal endometriosis (IEM) is a rare extra pelvic endometriosis. Here, we study the clinical characteristics, management strategies, and long-term gynecological outcomes of IEM patients at Beijing Chaoyang Hospital. CASE PRESENTATION: Three patients presented with a total of four lesions (one on the left side, one on the right side, and one bilaterally). The diameters of the four lesions were 2 cm, 2 cm, 3.5 cm and 1.5 cm, respectively. Two patients were admitted with inguinal hernias. Two patients were admitted with endometrioses-one with ovarian endometriosis and one with pelvic endometriosis. The hernia sac was repaired concomitantly via excision of the round ligament in two patients. One patient underwent a concomitant laparoscopy for gynecologic evaluations, including an ablation to the peritoneal endometriosis, and resection of the left uterosacral ligament endometriosis and pelvic adhesiolysis. All lesions were located on the extraperitoneal portion of the round ligament and were diagnosed histologically. No recurrence was observed in the inguinal region. All patients diagnosed with adenomyosis were treated with medication alone without any complaints. CONCLUSIONS: Inguinal endometriosis can occur simultaneously with pelvic endometriosis. In most cases, a concomitant hernia sac appears together with groin endometriosis. Clinical management should be individualized and performed in tandem with general practitioners and obstetrics & gynecology experts. Pelvic disease, in particular, should be followed-up by a gynecologist.


Subject(s)
Endometriosis , Laparoscopy , Round Ligament of Uterus , Endometriosis/complications , Endometriosis/diagnosis , Endometriosis/surgery , Female , Follow-Up Studies , Groin , Humans , Neoplasm Recurrence, Local , Round Ligament of Uterus/surgery
16.
J Cell Mol Med ; 24(16): 9409-9419, 2020 08.
Article in English | MEDLINE | ID: mdl-32628810

ABSTRACT

Prevention of infarct scar thinning and dilatation and stimulation of scar contracture can prevent progressive heart failure. Since microRNA 145 (miR-145) plays an important role in cardiac fibroblast response to wound healing and cardiac repair after an myocardial infarction (MI), using a miR-145 knock-out (KO) mouse model, we evaluated contribution of down-regulation of miR-145 to cardiac fibroblast and myofibroblast function during adverse cardiac remodelling. Cardiac function decreased more and the infarct size was larger in miR-145 KO than that in WT mice after MI and this phenomenon was accompanied by a decrease in cardiac fibroblast-to-myofibroblast differentiation. Quantification of collagen I and α-SMA protein levels as well as wound contraction revealed that transdifferentiation of cardiac fibroblasts into myofibroblasts was lower in KO than WT mice. In vitro restoration of miR-145 induced more differentiation of fibroblasts to myofibroblasts and this effect involved the target genes Klf4 and myocardin. MiR-145 contributes to infarct scar contraction in the heart and the absence of miR-145 contributes to dysfunction of cardiac fibroblast, resulting in greater infarct thinning and dilatation. Augmentation of miR-145 could be an attractive target to prevent adverse cardiac remodelling after MI by enhancing the phenotypic switch of cardiac fibroblasts to myofibroblasts.


Subject(s)
Cell Differentiation , MicroRNAs/antagonists & inhibitors , Myocardial Infarction/physiopathology , Myofibroblasts/pathology , Wound Healing , Animals , Cell Transdifferentiation , Cells, Cultured , Kruppel-Like Factor 4 , Mice , Mice, Inbred C57BL , Mice, Knockout , MicroRNAs/genetics , Myofibroblasts/metabolism
17.
J Neuroinflammation ; 17(1): 51, 2020 Feb 07.
Article in English | MEDLINE | ID: mdl-32028989

ABSTRACT

BACKGROUND: Radiotherapy is widely used and effective for treating brain tumours, but inevitably impairs cognition as it arrests cellular processes important for learning and memory. This is particularly evident in the aged brain with limited regenerative capacity, where radiation produces irreparable neuronal damage and activation of neighbouring microglia. The latter is responsible for increased neuronal death and contributes to cognitive decline after treatment. To date, there are few effective means to prevent cognitive deficits after radiotherapy. METHODS: Here we implanted hematopoietic stem cells (HSCs) from young or old (2- or 18-month-old, respectively) donor mice expressing green fluorescent protein (GFP) into old recipients and assessed cognitive abilities 3 months post-reconstitution. RESULTS: Regardless of donor age, GFP+ cells homed to the brain of old recipients and expressed the macrophage/microglial marker, Iba1. However, only young cells attenuated deficits in novel object recognition and spatial memory and learning in old mice post-irradiation. Mechanistically, old recipients that received young HSCs, but not old, displayed significantly greater dendritic spine density and long-term potentiation (LTP) in CA1 neurons of the hippocampus. Lastly, we found that GFP+/Iba1+ cells from young and old donors were differentially polarized to an anti- and pro-inflammatory phenotype and produced neuroprotective factors and reactive nitrogen species in vivo, respectively. CONCLUSION: Our results suggest aged peripherally derived microglia-like cells may exacerbate cognitive impairments after radiotherapy, whereas young microglia-like cells are polarized to a reparative phenotype in the irradiated brain, particularly in neural circuits associated with rewards, learning, and memory. These findings present a proof-of-principle for effectively reinstating central cognitive function of irradiated brains with peripheral stem cells from young donor bone marrow.


Subject(s)
Cognitive Dysfunction/therapy , Hematopoietic Stem Cell Transplantation , Maze Learning/physiology , Radiotherapy/adverse effects , Recovery of Function/physiology , Animals , Behavior, Animal/physiology , Cognitive Dysfunction/etiology , Dendritic Spines/physiology , Hippocampus/physiology , Humans , Long-Term Potentiation/physiology , Memory/physiology , Mice , Neurons/physiology , Spinocerebellar Ataxias/genetics , Treatment Outcome
18.
Parasitol Res ; 119(8): 2641-2648, 2020 Aug.
Article in English | MEDLINE | ID: mdl-32556503

ABSTRACT

Theileria species, with a broad geographic distribution, infect a wide range of both domestic and wild animals and are transmitted by ixodid ticks. Currently, there is no comprehensive report regarding the distribution of Theileria spp. in the eastern Tibetan Plateau, especially in Ganze Tibetan autonomous prefecture (153,700 km2) and Ngawa Tibetan and Qiang autonomous prefecture (84,242 km2) of Sichuan province, China. In this study, we collected blood samples from yaks (n = 144) (Bos grunniens), Tibetan sheep (n = 92), and Tibet horses (n = 142) in Ganze and Ngawa.Theileria sinensis, T. luwenshuni, and T. equi were the dominant Theileria species detected in yaks, Tibetan sheep, and horses with the total infection rates of 25.7% (37/144), 75.0% (69/92), and 51.4% (73/142), respectively. For ectoparasites, T. luwenshuni was the only Theileria species detected in sheep keds (Melophagus ovinus) with an infection rate of 30.8% (8/26). The total infection rates of T. sinensis in Haemaphysalis qinghaiensis, Dermacentor everestianus, and Rhipicephalus microplus were 34.6% (36/104), 34.0% (17/50), and 51.3% (58/113), respectively. Theileria spp., belonging to T. sergenti/buffeli/orientalis group, were only detected in R. microplus collected in Danba county of Ganze with a total infection rate of 39.9% (19/48). Our results provide important data of the epidemiology of Theileria spp. in livestock and ectoparasites and will assist with the implementation of measures to control theileriosis transmission in eastern Tibetan Plateau, China.


Subject(s)
Arachnid Vectors/parasitology , Livestock/parasitology , Theileria/isolation & purification , Theileriasis/epidemiology , Ticks/parasitology , Animals , Arachnid Vectors/classification , Cattle , Horses , Sheep , Theileria/classification , Theileriasis/parasitology , Theileriasis/transmission , Tibet/epidemiology , Ticks/classification
19.
J Mol Cell Cardiol ; 132: 36-48, 2019 07.
Article in English | MEDLINE | ID: mdl-31047986

ABSTRACT

BACKGROUND: Cardiac repair depends on angiogenesis and cell proliferation. Previously we identified Canopy 2 (CNPY2) as a secreted angiogenic growth factor which promotes neovascularization. We investigated the role of CNPY2 in cardiac repair following myocardial infarction (MI) and the possible mediators involved using Cnpy2 knockout (KO) mice and human cardiac tissue. METHODS AND RESULTS: Cardiac tissue from patients with end-stage heart failure had significantly lower endogenous CNPY2 expression compared to samples from control patients. CNPY2 expression in mouse hearts significantly decreased following MI. Significantly less leukocyte and endothelial cell proliferation was found in Cnpy2 KO than wild-type (WT) mice post MI which contributed to impaired angiogenesis, tissue repair, and decreased cardiac function (fractional shortening: WT: 21.1 ±â€¯2.1% vs. KO: 16.4 ±â€¯1.6%, p < .01 at day 28 post MI). RT-qPCR revealed significantly increased p16INK4a expression in Cnpy2 KO mouse hearts (WT: 1.0 ±â€¯0.04 vs. KO: 2.33 ±â€¯0.11 [relative expression of p16 INK4a], p < .01) which was confirmed by immunostaining (WT: 8.47 ±â€¯1.22 vs. KO: 12.9 ±â€¯1.22 [% total cells], p < .05) for the p16INK4a protein. Expression of cell cycle-related proteins, cyclin D1, cyclin-dependent kinases 4 and 6, and phosphorylated retinoblastoma protein (pRb) was significantly decreased in Cnpy2 KO mouse hearts. The up-regulation of the p16INK4a/cyclin D1/Rb pathway by knockout of Cnpy2 was accompanied by attenuation of PDK1/Akt phosphorylation. MI exacerbated the detrimental effects of p16INK4a on tissue repair in Cnpy2 KO mice. Overexpression of CNPY2 in the cardiac tissue of transgenic mice reversed the inhibition of cell proliferation through suppression of the p16INK4a pathway. CONCLUSIONS: Cardiac injury and progressive heart failure were associated with decreased CNPY2 levels in both humans and mice. Knockout of Cnpy2 resulted in up-regulation of p16INK4a which impaired cardiac function and tissue repair. These data suggest that CNPY2 is an important regulator of p16INK4a and promotes cell proliferation and tissue repair through inhibition of the p16INK4a pathway. CNPY2 treatment may offer a new approach to restore cardiac function after an MI.


Subject(s)
Adaptor Proteins, Signal Transducing/genetics , Cyclin-Dependent Kinase Inhibitor p16/genetics , Heart/physiology , Myocardium/metabolism , Signal Transduction/genetics , Animals , Cell Proliferation/genetics , Humans , Mice , Mice, Inbred C57BL , Mice, Knockout , Mice, Transgenic/genetics , Phosphorylation/genetics , Up-Regulation/genetics
20.
J Mol Cell Cardiol ; 132: 71-83, 2019 07.
Article in English | MEDLINE | ID: mdl-31047984

ABSTRACT

Bicuspid aortic valve (BAV) disease is a congenital abnormality that is associated with ascending aortic aneurysm yet many of the molecular mechanisms remain unknown. To identify novel molecular mechanisms of aneurysm formation we completed microarray analysis of the proximal (severely dilated) and distal (less dilated) regions of the ascending aorta from five patients with BAV. We identified 180 differentially expressed genes, 40 of which were validated by RT-qPCR. Most genes had roles in inflammation and endothelial cell function including cytokines and growth factors, cell surface receptors and the Activator Protein 1 (AP-1) transcription factor family (FOS, FOSB and JUN) which was chosen for further study. AP-1 was differentially expressed within paired BAV aneurysmal samples (n = 8) but not Marfan patients (n = 5). FOS protein was significantly enriched in BAV aortas compared to normal aortas but unexpectedly, ERK1/2 activity, an upstream regulator of FOS was reduced. ERK1/2 activity was restored when BAV smooth muscle cells were cultured in vitro. An mRNA-miRNA network within paired patient samples identified AP-1 as a central hub of miRNA regulation. FOS knockdown in BAV SMCs increased expression of miR-27a, a stretch responsive miRNA. AP-1 and miR-27a were also dysregulated in a mouse model of aortic constriction. In summary, this study identified a central role for AP-1 signaling in BAV aortic dilatation by using paired mRNA-miRNA patient sample. Upstream analysis of AP-1 regulation showed that the ERK1/2 signaling pathway is dysregulated and thus represents a novel chain of mediators of aortic dilatation in BAV which should be considered in future studies.


Subject(s)
Aortic Aneurysm/pathology , Aortic Diseases/pathology , Aortic Valve/abnormalities , Biomarkers/metabolism , Dilatation, Pathologic/pathology , Heart Valve Diseases/pathology , Animals , Aortic Aneurysm/genetics , Aortic Aneurysm/metabolism , Aortic Diseases/genetics , Aortic Diseases/metabolism , Aortic Valve/physiopathology , Bicuspid Aortic Valve Disease , Dilatation, Pathologic/genetics , Dilatation, Pathologic/metabolism , Disease Progression , Female , Gene Expression Profiling , Heart Valve Diseases/genetics , Heart Valve Diseases/metabolism , Heart Valve Diseases/physiopathology , Humans , Mice , Mice, Inbred C57BL , MicroRNAs/genetics , Signal Transduction
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