[Predict response to decitabine in patients with myelodysplastic syndrome and related neoplasms]

目的

探索预测骨髓增生异常综合征（MDS）及相关肿瘤地西他滨治疗反应的临床及分子学指标。

方法

回顾性分析109例接受地西他滨治疗的MDS及相关肿瘤患者临床资料，采用二代测序检测MDS常见突变基因的突变情况，分析患者临床特征及基因突变与地西他滨临床反应的关系。

结果

地西他滨中位疗程数为4（2~11）个，共74例（67.9%）患者获得治疗反应，其中30例（27.5%）获得完全缓解（CR）；35例（32.1%）患者无反应。单因素分析结果显示，国际预后积分系统（IPSS）中危2+高危、复杂核型、单体核型、7号染色体异常及1个疗程后PLT倍增的患者可获得更高的CR率。66.7%（14/21）的复杂核型患者、58.8%（10/17）的单体核型患者及66.7%（10/15）的TP53基因突变患者获得CR；TP53基因突变常合并复杂核型及单体核型；多因素分析显示TP53突变、1个疗程后PLT倍增及复杂核型是预测地西他滨治疗获得CR的独立预后因素，其中TP53突变是最强的预测因子（OR=4.39，95%CI 1.20~16.06，P=0.026）。

结论

TP53基因突变、1个疗程后PLT倍增及复杂核型可预测地西他滨完全缓解。

[The establishment of the immortalized mouse brain microvascular pericytes model and its preliminary application in screening of cerebrovascular toxicants]

Objective: To establish the immortalized mouse brain microvascular pericytes model and to apply to the cerebrovascular toxicants screening study. Methods: Brain pericytes were isolated from 3 weeks of mice by tissue digestion. Immortalized pericyte cell line was constructed by infecting with LT retrovirus. Monoclone was selected to purify the immortalized pericyte cell line. The pericyte characteristics and purity were explored by immunocytochemistry. Cell proliferation was measured by using the Pomega MTS cell Proliferation Colorimetric Assay Kit. Pericytes were treated with 0, 160, 320, 640, 1 280, 2 560 μmol/L lead acetate, 0, 5, 10, 20, 40, 80 μmol/L cadmium chloride and 0, 5, 10, 20, 40, 80 μmol/L sodium arsenite in 24 hours. Cell toxicity of each group was determined by MTS assay, median lethal dose (LD(50)) was calculated in linear regression. Results: Mouse brain pericytes were successfully isolated by tissue separation and enzyme digestion method. After immortalized by LT retroviruses, monoclone was selected and expanded to establish pericyte cell line. The brain pericytes exhibited typical long spindle morphology and positive staining for α-SMA and Vimentin. The proliferation of brain pericytes cell lines was very slowly, and the doubling time was about 48 hours. The proliferation of immortalized brain pericytes cell lines was very quickly, and the doubling time was about 24 hours. After lead acetate, cadmium chloride and sodium arsenite treatment for 24 hours respectively, gradual declines in cell viability were observed. The LD(50) of lead acetate was 2 025.0 μmol/L, the LD(50) of cadmium chloride was 36.6 μmol/L, and the LD(50) of sodium arsenite was 33.2 μmol/L. Conclusion: The immortalized mouse brain microvascular pericyte model is established successfully by infecting with LT retrovirus, and can be applied to screen cerebrovascular toxicants. The toxicity of these toxicants to immortalized mouse brain microvascular pericyte is in sequence: sodium arsenite,cadmium chloride, lead acetate.

Greenland records of aerosol source and atmospheric lifetime changes from the Eemian to the Holocene

The Northern Hemisphere experienced dramatic changes during the last glacial, featuring vast ice sheets and abrupt climate events, while high northern latitudes during the last interglacial (Eemian) were warmer than today. Here we use high-resolution aerosol records from the Greenland NEEM ice core to reconstruct the environmental alterations in aerosol source regions accompanying these changes. Separating source and transport effects, we find strongly reduced terrestrial biogenic emissions during glacial times reflecting net loss of vegetated area in North America. Rapid climate changes during the glacial have little effect on terrestrial biogenic aerosol emissions. A strong increase in terrestrial dust emissions during the coldest intervals indicates higher aridity and dust storm activity in East Asian deserts. Glacial sea salt aerosol emissions in the North Atlantic region increase only moderately (50%), likely due to sea ice expansion. Lower aerosol concentrations in Eemian ice compared to the Holocene are mainly due to shortened atmospheric residence time, while emissions changed little.

Past climate changes in Greenland ice were accompanied by large aerosol concentration changes. Here, the authors show that by correcting for transport effects, reliable source changes for biogenic aerosol from North America, sea salt aerosol from the North Atlantic, and dust from East Asian deserts can be derived.

[Progress in the diagnosis of florid cemento-osseous dysplasia]

Florid cemento-osseous dysplasia (FLCOD) is a rare, extensive bone metabolism disorder, which occurs only in the jaw bone. It is usually asymptomatic for a long time and discovered incidentally during a radiological examination. The characteristics of FLCOD in the initial stages are similar to those of periapical granuloma or jaw cyst, which may lead to misdiagnosis. After the lesion is mature, the imaging findings show that radiopaque with a thin radiolucent peripheral halo, which is crucial for the diagnosis of FLCOD, but other jaw lesions have similar imaging findings. Due to the poor blood supply of the lesion, the alveolar bone of root apices of vital teeth is slow to heal after trauma, increasing the chance of infection, which can lead to the osteomyelitis of the jaws and emerge sequestrum. This paper reviews the aspects of pathogenesis, clinical characteristics, diagnosis, differential diagnosis and treatment.

CCR2- and CCR2+ corneal macrophages exhibit distinct characteristics and balance inflammatory responses after epithelial abrasion

Macrophages are distributed throughout the body and are crucial for the restoration of damaged tissues. However, their characteristics in the cornea and roles in the repair of corneal injures are unclear. Here we show that corneal macrophages can be classified as CCR2^- macrophages, which already exist in the cornea at embryonic day 12.5 (E12.5) and are similar to yolk sac-derived macrophages, microglia, in phenotype and gene expression, and CCR2⁺ macrophages, which do not appear in the cornea until E17.5. At a steady state, CCR2^- corneal macrophages have local proliferation capacity and are rarely affected by monocytes; however, following corneal epithelial abrasion, most CCR2^- corneal macrophages are replaced by monocytes. In contrast, CCR2⁺ macrophages are repopulated by monocytes under both a steady-state condition and following corneal wounding. Depletion of CCR2⁺ macrophages decreases corneal inflammation after epithelial abrasion, whereas depletion of CCR2^- macrophages increases inflammation of the injured cornea. Loss of either cell type results in a delay in corneal healing. These data indicate that there are two unique macrophage populations present in the cornea, both of which participate in corneal wound healing by balancing the inflammatory response.

Depressive symptoms and inflammation are independent risk factors of fatigue in breast cancer survivors

BACKGROUND

Psychosocial and inflammatory factors have been associated with fatigue in breast cancer survivors. Nevertheless, the relative contribution and/or interaction of these factors with cancer-related fatigue have not been well documented.

METHOD

This cross-sectional study enrolled 111 stage 0-III breast cancer patients treated with breast surgery followed by whole breast radiotherapy. Fatigue was measured by the total score of the Multidimensional Fatigue Inventory-20. Potential risk factors included inflammatory markers (plasma cytokines and their receptors and C-reactive protein; CRP), depressive symptoms (as assessed by the Inventory of Depressive Symptomatology-Self Reported), sleep (as assessed by the Pittsburgh Sleep Quality Index) and perceived stress (as assessed by the Perceived Stress Scale) as well as age, race, marital status, smoking history, menopause status, endocrine treatment, chemotherapy and cancer stage. Linear regression modeling was employed to examine risk factors of fatigue. Only risk factors with a significance level <0.10 were included in the initial regression model. A post-hoc mediation model using PROCESS SPSS was conducted to examine the association among depressive symptoms, sleep problems, stress, inflammation and fatigue.

RESULTS

At 1 year post-radiotherapy, depressive symptoms (p<0.0001) and inflammatory markers (CRP: p = 0.015; interleukin-1 receptor antagonist: p = 0.014; soluble tumor necrosis factor receptor-2: p = 0.009 in separate models) were independent risk factors of fatigue. Mediation analysis showed that depressive symptoms also mediated the associations of fatigue with sleep and stress.

CONCLUSIONS

Depressive symptoms and inflammation were independent risk factors for cancer-related fatigue at 1 year post-radiotherapy, and thus represent independent treatment targets for this debilitating symptom.

An investigation into UK medical students’ knowledge of lifestyle factors on cancer

Background and aim

Lifestyle factor modification (alcohol, smoking, obesity, diet, physical activity) has the potential to reduce cancer incidence and cancer survival. This study assessed the knowledge of lifestyle factors and cancer in undergraduate medical students.

Methods and results

A total of 218 students (7 UK universities) completed an online survey of nine questions in three areas: knowledge (lifestyle factors and cancer); information sources; clinical practice (witnessed clinical counselling). Diet, alcohol, smoking and physical activity were recognised as lifestyle factors by 98% of responders, while only 69% reported weight. The links of lung cancer/smoking and alcohol/liver cancer were recognised by >90%, while only 10% reported weight or physical activity being linked to any cancer. University teaching on lifestyle factors and cancer was reported by 78%: 34% rating it good/very good. GPs were witnessed giving lifestyle advice by 85% of responders.

Conclusions

Most respondents were aware of a relationship between lifestyle factors and cancer, mainly as a result of undergraduate teaching. Further work may widen the breadth of knowledge, and potentially improve primary and secondary cancer prevention.

Retarding field analyzer for the EAST plasma boundary

A novel bi-directional Retarding Field Analyzer (RFA) probe has been installed on a fast reciprocating drive system on the Experimental Advanced Superconducting Tokamak (EAST) to measure the ion temperature and fast electron fluxes. A Langmuir probe assembly was added on the top of the RFA head to control the RFA position relative to the last closed flux surface and to have a possibility to measure the electron density and temperature as well. Except the ion temperature, the fast electron fluxes from both ion and electron drift sides have been measured during lower hybrid current drive. The RFA probe has been also used to measure the fast electrons associated with edge localized modes (ELMs), indicating their substantial presence in the scrape-off-layer plasma of EAST.

[Study of abnormal iron metabolism parameters and iron overload in patients with myelodysplastic syndromes]

Objective: To investigate the abnormalities of iron metabolism parameters, the prevalence and risk factors of iron overload and clinical characteristics of patients with myelodysplastic syndromes(MDS). Methods: Retrospective investigation was used to observe abnormal iron metabolism parameters and clinical characteristics of newly diagnosed 94 MDS patients in our center from June 2015 to March 2016. Results: Of 94 patients, 71(75.53%)had a hemoglobin level of less than 100 g/L at diagnosis. Iron overload was observed in 52(55.32%)of 94 MDS patients, in which a higher prevalence of iron overload was observed in low risk groups(IPSS low/Int-1 risk groups)than higher risk groups(Int-2/high risk groups). Higher levels of serum iron(SI)[36.5(8.5-64.7)mmol/L vs 25.2(3.7-45.3)mmol/L, P<0.01], transferrin saturation(TSAT)[43.5(12.2-77.2)% vs 53.4(14.8-97.5)%, P <0.01]and serum ferritin(SF)were observed in iron overload group. No differences of labile cellular iron(LCI)and reactive oxygen species(ROS)were observed between two groups(P=0.88, P=0.06). As the results of clinical complication of iron overload, alanine aminotransferase(ALT)[25(3-158)U/L vs 16(5-80)U/L, P=0.03]and type B natriuretic peptide precursor(proBNP)[190(6-4281)ng/L vs 84(12-2 275)ng/L, P= 0.05]levels were increased in iron overload group. There was no significant difference in iron metabolism parameters between patients with refractory anemia(RARS)and non RARS patients(P>0.05). Both frequency and volume of RBC transfusion had a significant effect on all iron metabolism parameters(SI, TSAT and SF)(P <0.01)except LCI and ROS. Excluded the patients with history of blood transfusion and SF levels over 1 000 μg/L, higher levels of LCI were mainly observed in dysplastic erythropoiesis and increased bone marrow erythroblasts ratio groups(P<0.01, P<0.05). Conclusion: The main cause of iron overload in MDS is chronic transfusion therapy. Both frequency and intensity of transfusion regimen have a main effect on iron metabolism parameters. LCI levels are mainly increased in newly diagnosed patients with the abnormalities of iron metabolism and have a stronger association with dysplastic erythropoiesis and increased bone marrow erythroblasts ratio. As the toxic fraction of iron and its negative impact on MDS, iron overload monitoring and chelation treatment decision can also be supported by LCI.