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41.

Purpose

Previous studies have found that some immune-related genes were associated with autoimmune thyroid diseases (AITDs). A couple of studies have explored the association between vitamin D (1,25-dihydroxyvitamin D3) receptor (VDR) gene polymorphisms and susceptibility to AITDs in different populations and found conflicting results. This case-control study was designed to evaluate the role of polymorphisms of VDR gene in the predisposition of AITDs in a Chinese Han population.

Methods

A total of 417 patients with Graves’ disease (GD), 250 patients with Hashimoto's thyroiditis (HT) and 301 healthy subjects were enrolled. The Matrix Assisted Laser Desorption Ionization-Time of Flight Mass Spectrometer (MALDI-TOF-MS) Platform was applied to detect four SNPs (rs1544410, rs2228570, rs731236 and rs7975232) in the VDR gene.

Results

In the rs7975232 allele A frequency showed a significant increase in GD patients (30.34% vs. 25.42% in controls; P = 0.041, OR = 1.278, 95%CI = 1.010–1.617). However, no relationship was found between clinical phenotypes and the four SNPs.

Conclusions

This result suggests that the VDR gene may be one susceptibility gene which contributes to the risk of GD.  相似文献   
42.
We summarized the findings of toxicity studies on graphene-based nanomaterials (GNMs) in laboratory mammals. The inhalation of graphene (GP) and graphene oxide (GO) induced only minimal pulmonary toxicity. Bolus airway exposure to GP and GO caused acute and subacute pulmonary inflammation. Large-sized GO (L-GO) was more toxic than small-sized GO (S-GO). Intratracheally administered GP passed through the air-blood barrier into the blood and intravenous GO distributed mainly in the lungs, liver, and spleen. S-GO and L-GO mainly accumulated in the liver and lungs, respectively. Limited information showed the potential behavioral, reproductive, and developmental toxicity and genotoxicity of GNMs. There are indications that oxidative stress and inflammation may be involved in the toxicity of GNMs. The surface reactivity, size, and dispersion status of GNMs play an important role in the induction of toxicity and biodistribution of GNMs. Although this review paper provides initial information on the potential toxicity of GNMs, data are still very limited, especially when taking into account the many different types of GNMs and their potential modifications. To fill the data gap, further studies should be performed using laboratory mammals exposed using the route and dose anticipated for human exposure scenarios.  相似文献   
43.
44.
The present investigation was performed to examine the effect of artemether on rat pregnancy and embryonic/fetal development during different phases of pregnancy. Artemether was administered orally to Wistar rats at doses 3.5 and 7 mg/kg during blastogenesis, organogenesis and fetal period. When administered during blastogenesis, the preimplantation loss, number of implantations, resorptions, living fetuses, external and skeletal examination did not differ from those of control, however the higher dose induced reduction in fetal body weight and caused pre-term delivery in 3 of 10 pregnant rats. During organogenesis complete fetal resorption was observed in all dams treated with the higher dose, while in the lower dose 32% of implants were resorbed and live fetuses showed decreased fetal weight with low incidence of skeletal retardation. Artemether did not adversely affect prenatal development in rats treated during the fetal period although the higher dose level induced reduction in fetal body weight. In conclusion, no evidence of maternal toxicity, artemether was embryolethal at 3.5 and 7 mg/kg when dosed during organogenesis, the surviving fetuses showed fetal growth retardation without incidence of malformations, treatment during blastogenesis and fetal period had no lethal or teratogenic effect although the mean fetal body weight was significantly lower than control.  相似文献   
45.
Exposure to polychlorinated biphenyls impairs cognition and behavior in children. Two environmental PCBs 2,2',3,3',4,4',5-heptachlorobiphenyl (PCB170) and 2,2',3,5',6-pentachlorobiphenyl (PCB95) were examined in vitro for influences on synaptic transmission in rat hippocampal slices. Field excitatory postsynaptic potentials (fEPSPs) were recorded in the CA1 region using a multi-electrode array. Perfusion with PCB170 (10 nM) had no effect on fEPSP slope relative to baseline period, whereas (100 nM) initially enhanced then depressed fEPSP slope. Perfusion of PCB95 (10 or 100 nM) persistently enhanced fEPSP slope > 200%, an effect that could be inhibited by dantrolene, a drug that attenuates ryanodine receptor signaling. Perfusion with picrotoxin (PTX) to block GABA neurotransmission resulted in a modest increase in fEPSP slope, whereas PTX + PCB170 (1-100 nM) persistently enhanced fEPSP slope in a dose dependent manner. fEPSP slope reached > 250% of baseline period in the presence of PTX + 100 nM PCB170, conditions that evoked marked epileptiform after-potential discharges. PCB95 and PCB170 were found to differentially influence the Ca2+-dependence of [3H]ryanodine-binding to hippocampal ryanodine receptors. Non-coplanar PCB congeners can differentially alter neurotransmission in a manner suggesting they can elicit imbalances between inhibitory and excitatory circuits within the hippocampus. Differential sensitization of ryanodine receptors by Ca2+ appears to mediate, at least in part, hippocampal excitotoxicity by non-coplanar PCBs.  相似文献   
46.
Jiang J  Ma L  Yuan L  Wang X  Zhang W 《Toxicology》2007,232(3):286-293
The objective of this study was to establish a hypospadiac rat model by maternal exposure to di-n-butyl phthalate (DBP) and to evaluate the developmental abnormalities of hypospadiac male rats. Timed-pregnant rats were given DBP by gastric intubation at doses of 0, 250, 500, 750 or 1000 mg/kg body weight (bw)/day from gestation day (GD) 14 to 18 to establish a hypospadiac rat model. The hypospadias was observed in the 500 and 750 mg/kg bw/day groups, the incidence of which was 6.8 and 41.3%, respectively. Transverse serial histological analysis of genitalia of hypospadiac male rats confirmed the malformation. With exposed dose increasing, the serum testosterone (T) levels of male rats inversely decreased, and in the same dosage group the serum T levels of hypospadiac rats were significantly lower than the levels of nonhypospadiac counterparts. The other reproductive lesions such as cryptorchidism and decreased ratio of anogenital distance/body weight (AGD/bw) were also observed. Autopsy analysis revealed the development of reproductive organs (prostate, testes, epididymis, pituitary gland) and nonreproductive organs (adrenal gland, liver, kidney, heart, spleen) of hypospadiac rats and nonhypospadiac counterparts. The results indicated that the reproductive system and developmental condition of hypospadiac male offspring were damaged severely by DBP.  相似文献   
47.
BackgroundImmunotherapy with chimeric antigen receptor (CAR) T cells is actively being explored for pediatric brain tumors in preclinical models and early phase clinical studies. At present, it is unclear which CAR target antigens are consistently expressed across different pediatric brain tumor types. In addition, the extent of HLA class I expression is unknown, which is critical for tumor recognition by conventional αβTCR T cells.MethodsWe profiled 49 low- and high-grade pediatric brain tumor patient-derived orthotopic xenografts (PDOX) by flow analysis for the expression of 5 CAR targets (B7-H3, GD2, IL-13Rα2, EphA2, and HER2), and HLA class I. In addition, we generated B7-H3-CAR T cells and evaluated their antitumor activity in vitro and in vivo.ResultsWe established an expression hierarchy for the analyzed antigens (B7-H3 = GD2 >> IL-13Rα2 > HER2 = EphA2) and demonstrated that antigen expression is heterogenous. All high-grade gliomas expressed HLA class I, but only 57.1% of other tumor subtypes had detectable expression. We then selected B7-H3 as a target for CAR T-cell therapy. B7-H3-CAR T cells recognized tumor cells in an antigen-dependent fashion. Local or systemic administration of B7-H3-CAR T cells induced tumor regression in PDOX and immunocompetent murine glioma models resulting in a significant survival advantage.ConclusionsOur study highlights the importance of studying target antigen and HLA class I expression in PDOX samples for the future design of immunotherapies. In addition, our results support active preclinical and clinical exploration of B7-H3-targeted CAR T-cell therapies for a broad spectrum of pediatric brain tumors.  相似文献   
48.
Adult‐onset neuroblastoma is rare and little is known about its biology and clinical course. There is no established therapy for adult‐onset neuroblastoma. Anti‐GD2 immunotherapy is now standard therapy in children with high‐risk neuroblastoma; however, its use has not been reported in adults. Forty‐four adults (18–71 years old) diagnosed with neuroblastoma between 1979 and 2015 were treated at Memorial Sloan Kettering Cancer Center. Five, 1, 5 and 33 patients had INSS stage 1, 2, 3 and 4 diseases, respectively. Genetic abnormalities included somatic ATRX (58%) and ALK mutations (42%) but not MYCN‐amplification. In the 11 patients with locoregional disease, 10‐year progression‐free (PFS) and overall survival (OS) was 35.4 ± 16.1% and 61.4 ± 15.3%, respectively. Among 33 adults with stage 4 neuroblastoma, 7 (21%) achieved complete response (CR) after induction chemotherapy and/or surgery. Seven patients with primary refractory neuroblastoma (all with osteomedullary but no soft tissue disease) received anti‐GD2 antibodies, mouse or humanized 3F8. Antibody‐related adverse events were similar to those in children, response rate being 71.4%. In patients with stage 4 disease at diagnosis, 5‐year PFS was 9.7± 5.3% and most patients who were alive with disease at 5 years died of neuroblastoma over the next 5 years, 10‐year OS being only 19.0 ± 8.2%. Patients who achieved CR after induction had superior PFS and OS (p = 0.006, p = 0.031, respectively). Adult‐onset neuroblastoma appeared to have different biology from pediatric or adolescent NB, and poorer outcome. Complete disease control appeared to improve long‐term survival. Anti‐GD2 immunotherapy was well tolerated and might be beneficial.  相似文献   
49.
Human serum butyrylcholinesterase (Hu BChE) is a stoichiometric bioscavenger that is being developed as a prophylactic countermeasure against organophosphorus nerve agents. This study was designed to evaluate the efficacy of Hu BChE against whole-body inhalation exposure to a lethal dose of sarin (GB) vapor. Male Göttingen minipigs were subjected to: air exposure, GB vapor exposure, or pretreatment with Hu BChE followed by GB vapor exposure. Hu BChE was administered by i.m. injection 24 h prior to exposure to 4.1 mg/m3 of GB vapor for 60 min. Electrocardiograms (ECG), electroencephalograms (EEG), and pupil size were recorded throughout exposure. Blood drawn before and throughout exposure was analyzed for blood gases, electrolytes, metabolites, acetylcholinesterase and BChE activities, and amount of GB present. Untreated animals exposed to GB vapor exhibited cardiac abnormalities and generalized seizures, ultimately succumbing to respiratory failure. Pretreatment with 3.0 or 6.5 mg/kg of Hu BChE delayed blood gas and acid–base disturbances and the onset of cardiac and neural toxic signs, but failed to increase survivability. Pretreatment with 7.5 mg/kg of Hu BChE, however, completely prevented toxic signs, with blood chemistry and ECG and EEG parameters indistinguishable from control during and after GB exposure. GB bound in plasma was 200-fold higher than plasma from pigs that did not receive Hu BChE, suggesting that Hu BChE scavenged GB in blood and prevented it from reaching other tissues. Thus, prophylaxis with Hu BChE alone not only increased survivability, but also prevented cardiac abnormalities and neural toxicity in minipigs exposed to a lethal dose of GB vapor.  相似文献   
50.
Introduction: Current therapeutic approaches for high-risk neuroblastoma (HR-NB) include high-dose chemotherapy, surgery and radiotherapy; interventions that are associated with long and short-term toxicities. Effective immunotherapy holds particular promise for improving survival and quality of life by reducing exposure to cytotoxic agents. GD2, a surface glycolipid is the most common target for immunotherapy.

Areas covered: We review the status of anti-GD2 immunotherapies currently in clinical use for neuroblastomas and novel GD2-targeted strategies in preclinical development.

Expert commentary: Anti-GD2 monoclonal antibodies are associated with improved survival in patients in their first remission and are increasingly being used for chemorefractory and relapsed neuroblastoma. As protein engineering technology has become more accessible, newer antibody constructs are being tested. GD2 is also being targeted by natural killer cells and T-cells. Active immunity can be elicited by anti-GD2 vaccines. The rational combination of currently available and soon-to-emerge immunotherapeutic approaches, and their integration into conventional multimodality therapies will require further investigation to optimize their use for HR-NB.  相似文献   

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