2016—2018年河南省儿童医院细菌分布及耐药性分析

目的 了解河南省儿童医院2016—2018年临床分离菌株的分布及常用抗菌药物的耐药情况,为儿科临床合理用药提供依据。方法 选择2016—2018年所有临床分离菌株,采用Phoenix 100微生物分析仪和纸片扩散法进行药敏实验,按照历年CLSI标准判读药敏结果,用WHONET5.6软件进行耐药性分析。 结果 2016—2018年共收集临床非重复分离株21404株,其中革兰阳性菌7772株,占36.3%,革兰阴性菌13632株,占63.7%。无菌体液标本共分离出致病菌2312株,排在前三位的细菌为凝固酶阴性葡萄球菌、大肠埃希菌和肺炎克雷伯菌。 3105株非脑脊液分离的肺炎链球菌中青霉素不敏感率为0.5%。耐甲氧西林金黄色葡萄球菌(MRSA)和凝固酶阴性葡萄球菌(MRCNS)平均检出率分别为34.2%和72.0%;MRSA和MRCNS对绝大多数测试抗菌药物的耐药率均显著高于甲氧西林敏感株金黄色葡萄球菌(MSSA)和凝固酶阴性葡萄球菌(MSCNS)。对万古霉素和利奈唑胺不敏感的葡萄球菌未检出。检出耐万古霉素屎肠球菌1株,未发现对万古霉素不敏感的粪肠球菌。流感嗜血菌β-内酰胺酶阳性率为53.7%,除了对复方磺胺甲噁唑的耐药率高于80.0%外,对大多数抗菌药物比较敏感。 2016—2018年大肠埃希菌产超广谱β-内酰胺酶(ESBL)的检出率依次为70.4%、72.1%和66.6%,大肠埃希菌对碳青霉烯仍高度敏感,3年来其对碳青霉烯类药物的耐药率都低于10.0%。2016—2018年肺炎克雷伯菌产ESBL检出率依次为61.3%、75.6%和72.0%,对亚胺培南的耐药率为39.3%、32.7%和43.1%,对美罗培南的历年耐药率为40.4%、30.8%和43.2%。铜绿假单胞菌对亚胺培南和美罗培南的耐药率分别为22.8%和19.6%。鲍曼不动杆菌对美罗培南和亚胺培南的耐药率均为60.5%。结论 多重耐药细菌在儿童中的形势严峻,威胁着儿科临床的抗感染治疗,应加强耐药监测和采取行之有效的感染控制措施。     

细菌基因工程药物研究进展

采用肠道益生菌重构肠道生态平衡,治疗各种代谢相关慢性疾病,是当前保健和医疗行业的热门研究领域。由于人群个体差异,益生菌的治疗效果并不稳定。采用合成生物学手段,将具有特殊治疗作用的功能片段导入益生菌中,创造具有靶向治疗效果的细菌活体药物,对医药发展具有重要影响。本文阐述以各种细菌为治疗载体的活体药物研究进展,包括用于疾病治疗的细菌种类优势、封存技术以及所携带效应物的表达调控。     

Temperature-dependent variations in toxicity of diamide insecticides against three lepidopteran insects

The effect of temperature on the toxicities of four diamide insecticides (chlorantraniliprole, cyantraniliprole, flubendiamide, tetraniliprole) against three lepidopteran insects (Helicoverpa armigera, Plutella xylostella, Athetis lepigone) were determined from 15 to 35 °C by exposing third-instar larvae to dip-treated cabbage leaf. The results indicated that increase in temperature led to an increase significantly and regularly in the toxicities of the four diamide insecticides against P. xylostella and H. armigera, but not for A. lepigone. The temperature coefficients (TCs) of the four diamide insecticides increased from 15 to 35 °C. Tetraniliprole for H. armigera (+825.83), chlorantraniliprole for P. xylostella (+315.65) and cyantraniliprole for H. armigera (+225.77) exhibited high positive TCs. For A. lepigone, temperature had a positively weak or no effect on the toxicities of most of the diamide insecticides from 20 to 30 °C, but a higher effect from 30 to 35 °C. In addition, the toxicities of chlorantraniliprole, cyantraniliprole and tetraniliprole all decreased from 15 to 20 °C. This study can guide pest managers in choosing suitable ambient field temperature when spraying diamide insecticides against lepidopteran insects.     

Fitness costs in chlorfenapyr-resistant populations of the chive maggot,Bradysia odoriphaga

The chive maggot, Bradysia odoriphaga (Yang and Zhang) is an economically important insect pest, affecting many key vegetables, including Chinese chive, especially in northern China. Chlorfenapyr, a halogenated pyrrole insecticide that interferes with mitochondrial oxidative phosphorylation is widely used against B. odoriphaga. In this study, we evaluated selection-induced resistance to chlorfenapyr and fitness costs in B. odoriphaga. The results showed that B. odoriphaga developed 43.32-fold resistance after continuous exposure to chlorfenapyr for over 10 consecutive generations. The life-history traits of chlorfenapyr-resistant and susceptible strains were compared using age-stage, two-sex life table approach. No significant effects were observed on the longevity and pre-adult period. However, reduction in the total pre-oviposition period (TPOP) and fecundity (eggs/female) were observed in the resistant strain. Moreover, the demographic parameters such as intrinsic rate of increase (r), net reproductive rate (R0) and finite rate of increase (λ) were also decreased significantly in the resistant strain compared to the susceptible strain. These results showed the potential of B. odoriphaga to develop resistance against chlorfenapyr under continuous selection pressure. Furthermore, there was a fitness cost linked with chlorfenapyr resistance in B. odoriphaga. We conclude that a better knowlegde on the trade-off at play between resistance degree and fitness cost could be crucial for developing further management of B. odoriphaga in China.     

Characterization of Craniocervical Artery Dissection by Simultaneous MR Noncontrast Angiography and Intraplaque Hemorrhage Imaging at 3T

BACKGROUND AND PURPOSE:Craniocervical artery dissection is the most common cause of ischemic stroke identified in young adults. For the diagnosis of craniocervical artery dissection, multisequence MR imaging is recommended but is time-consuming. Recently, investigators proposed a simultaneous noncontrast angiography and intraplaque hemorrhage imaging technique allowing simultaneous noncontrast MRA and vessel wall imaging in a single scan. This study sought to investigate the feasibility of 3D simultaneous noncontrast angiography and intraplaque hemorrhage MR imaging in the characterization of craniocervical artery dissection.MATERIALS AND METHODS:Twenty-four symptomatic patients (mean age, 45.0 ± 16.1 years; 21 men) with suspected craniocervical artery dissection were recruited. The 3D simultaneous noncontrast angiography and intraplaque hemorrhage 3D TOF MRA and black-blood imaging sequences were performed on a 3T MR imaging scanner. The agreement between simultaneous noncontrast angiography and intraplaque hemorrhage imaging and multisequence MR imaging in evaluating arterial dissection was determined.RESULTS:Dissection was found to involve 1 artery in 22 patients and 2 arteries in 2 patients. The intramural hematoma and luminal occlusion were detected in 19 (79.2%) and 11 (45.8%) patients, respectively. In measuring stenosis, the Cohen κ value between 3D TOF MRA and simultaneous noncontrast angiography and intraplaque hemorrhage imaging was 0.82 (P < .001). All intramural hematomas on multisequence imaging were successfully identified by simultaneous noncontrast angiography and intraplaque hemorrhage imaging.CONCLUSIONS:3D simultaneous noncontrast angiography and intraplaque hemorrhage imaging showed excellent agreement with multisequence MR imaging in evaluating luminal stenosis and intramural hematoma in patients with craniocervical artery dissection. The simultaneous noncontrast angiography and intraplaque hemorrhage imaging saved nearly 50% of scanning time compared with multisequence MR imaging. Our findings suggest that 3D simultaneous noncontrast angiography and intraplaque hemorrhage imaging might be an alternative, time-efficient diagnostic tool for craniocervical artery dissection.

Craniocervical artery dissection (CCAD) is the most common cause of stroke identified in young and middle-aged adults.^1,2 Pathophysiologically, arterial dissections occur when a tear develops in ≥1 layer of the vessel wall, allowing blood to enter the wall and split the layers; this condition is characterized by a cavity or intramural hematoma (IMH).³ The increased volume of the IMH may narrow or occlude the lumen, and it can also damage the intima and trigger thrombosis. Because this arterial disorder is strongly associated with acute ischemic events,^4,5 it is clinically preferable to diagnose CCAD at the early stages so that clinicians can properly treat and prevent potential neurologic complications.⁶Angiographic imaging modalities, such as CTA, MRA, and DSA, have been widely used for the diagnosis of CCAD in clinical settings.^7–9 These approaches can only provide the information of luminal narrowing or occlusion but are unable to directly delineate IMH, which is a key sign of CCAD. Some investigators believe that craniocervical arteries with occlusion but without evidence of IMH cannot be diagnosed as dissection unless the dissected wall is completely recanalized.¹⁰ MR vessel wall imaging has been increasingly used for the diagnosis of CCAD due to its capability of directly visualizing IMH in the vessel wall.^11–13 Recently, a multisequence MR imaging protocol, which includes both MRA and MR vessel wall imaging sequences, was recommended for the diagnosis of CCAD.¹⁰ However, this protocol needs independent acquisition of 2 different time-consuming MR imaging sequences.Most recently, a simultaneous noncontrast angiography and intraplaque hemorrhage (SNAP) MR imaging technique has been proposed for the evaluation of vulnerable carotid atherosclerotic plaques.¹⁴ The major advantage of the 3D SNAP imaging sequence is acquiring noncontrast MRA and vessel wall images simultaneously in a single scan. The vessel wall images derived from the 3D SNAP sequence carry heavy T1-weighting, which is very sensitive to intraplaque hemorrhage or IMH. The other advantages of SNAP imaging include fast scanning, large longitudinal coverage (up to 250 mm), and isotropic high resolution (0.8 mm³). Those advantages make SNAP an ideal candidate for quick and reliable identification of dissection, particularly for tortuous craniocervical arteries with longer lesions.We hypothesized that the 3D SNAP MR imaging technique is capable of characterizing CCAD by providing both luminal and vessel wall information simultaneously. In this study, we sought to evaluate the feasibility of 3D SNAP MR imaging in the diagnosis of CCAD.     

The incidence of radioepidermitis and the dose-response relationship in parotid gland cancer patients treated with 125I seed brachytherapy

Background

We studied the incidence and dose–response relationship of radioepidermitis in parotid gland carcinoma patients treated with [¹²⁵I] seed brachytherapy in the hopes of designing an optimized pre-implant treatment plan that would reduce the incidence and severity of radioepidermitis in patients receiving this therapy.

Patients and methods

Between January 2007 and May 2010, 100 parotid gland cancer patients were treated postoperatively with [¹²⁵I] seed brachytherapy. The matched peripheral dose (MPD) was 80–140 Gy, and [¹²⁵I] seed activity was 0.7–0.8 mCi. The mean dose delivered to the skin was calculated in the post-implant CT on day 0 following implantation. Grades of acute and late dermatitis were evaluated at 2, 6, 12, and 18 months post-implantation.

Results

Most patients experienced grade 0–2 acute and late skin side effects (86 and 97?%, respectively), though a small subset developed severe complications. Most grade 1–3 effects resolved within 6 months of implantation, though some grade 1–3 effects and all grade 4 effects remained unchanged throughout the 18-month follow-up period. Grade 3 and 4 effects were most prominent (75 and 25?%, respectively) with doses of 110–140 Gy; doses higher than 140 Gy produced only grade 4 effects.

Conclusion

[¹²⁵I] seed brachytherapy produced acceptable levels of acute and late radioepidermitis with a good clinical outcome. A mean dose under 100 Gy delivered to the skin was safe, though doses of 110–140 Gy should be given with caution and extra monitoring; doses greater than 140 Gy are dangerous and likely to produce grade 4–5 effects.

     

低管电压联合迭代模型重建技术在肝脏CT增强扫描中的可行性研究

目的 探讨低管电压联合迭代模型重建(IMR)技术在肝脏CT增强扫描中的可行性。方法 60例患者按随机数字表法分为A组和B组,每组30例。扫描方案A组动脉期100 kV,门静脉期120 kV,B组动脉期120 kV,门静脉期100 kV。各组管电流均固定为250 mAs。A组动脉期和B组门静脉期采用IMR,A组门静脉期和B组动脉期采用滤波反投影(FBP)重建,得到4组图像,包括A1组(动脉期,100 kV,IMR),B1组(动脉期,120 kV,FBP),A2组(门静脉期,120 kV,FBP)以及B2组(门静脉期,100 kV,IMR)。分别比较A1组和B1组,A2组和B2组的图像质量客观评价指标 [图像噪声、图像信噪比(SNR)、对比噪声比(CNR)] 和主观评价指标(低对比分辨力、病灶边缘锐利度、图像失真及诊断信心度),并计算有效剂量。结果 有效剂量A1组较B1组、B2组较A2组明显下降(t=11.05、11.64, P<0.01)。低对比分辨力、病灶边缘锐利度A1优于B1组、 B2优于A2组(Z=6.391、3.200、6.559、3.409, P<0.01),图像失真和诊断信心差异无统计学意义(P>0.05)。图像噪声A1组低于B1组,B2组低于A2组(t=12.889、15.163, P<0.01),SNR和CNR A1组高于B1组,B2组高于A2组(t=15.458、1.325、15.308、3.136, P<0.01)。结论 与常规管电压FBP重建相比,低管电压联合IMR重建可显著降低肝脏增强CT的辐射剂量,并提高其图像质量。     

Therapeutic effects of transarterial infusion of lipiodol and ethanol in various ratios in a rabbit VX2 tumor model

PUSRPOSE

We aimed to evaluate the therapeutic effect and safety of transcatheter arterial embolization with various volume ratios of lipiodol and ethanol in a rabbit VX2 tumor model to identify the optimal volume ratio.

METHODS

Eighteen adult male New Zealand white rabbits implanted with VX2 tumors in their left liver lobes were randomly divided into six groups based on volume ratios of lipiodol to ethanol: group A, 3:1; group B, 2:1; group C, 1:1; group D, 1:2; group E, 1:3; and group F, 1:4. Pre- and post-treatment unenhanced magnetic resonance imaging was used to detect tumor formation and evaluate tumor growth rates. Liver samples were harvested one week after the procedure, and apoptosis index of tumor tissues was evaluated by pathologic examination and TUNEL assay.

RESULTS

Tumor size decreased in groups B, C, and D, but increased in groups A, E, and F. Tumor growth rates in groups A–F were 0.40±0.03, −0.11±0.21, −0.08±0.09, −0.12±0.07, 0.06±0.12, and 0.05±0.09, respectively. The change in tumor size was significantly different in group A compared with the rest of the groups, but no significant difference was observed among groups B–F. Apoptosis indexes of the six groups were 4.7±2.1%, 6.7±2.1%, 11.7±3.1%, 11.0±2.0%, 10.7±3.2%, and 12±3%, respectively. Apoptosis index was significantly lower in group A compared with groups C–F (P < 0.05). Apoptosis index of group B was significantly lower than groups C and F. There was no significant difference among the other groups.

CONCLUSION

The volume ratios of lipiodol to ethanol ranging from 2:1 to 1:4 were equally effective, the ratios 2:1 and 1:3 had equal safety, and the ratios 1:1 and 1:2 indicated better long-term therapeutic effect. Increasing ethanol in the mixture caused more severe liver injury. Optimal efficacy and safety was achieved with a lipiodol to ethanol volume ratio of 1:1.Hepatocellular carcinoma (HCC) is one of the most common solid malignancies in the world (1). Transarterial chemoembolization (TACE) is widely used to treat HCC patients who are not suitable candidates for curative treatments (2–5). The most common embolic agent used in TACE is lipiodol, which can be mixed with surgical glues (cyanoacrylates) or with ethanol for interventional procedures. Ethanol was confirmed to be effective in occluding the hepatic arterial system, but it can cause perisinusoidal fibrosis (6). Transarterial ethanol ablation (TEA) with a mixture of lipiodol-ethanol has been shown to be an effective treatment for HCC (7). Yu et al. (8) reported that the embolization efficacy and treatment effectiveness of TEA were probably superior to those of TACE for HCC, and a decreased proportion of ethanol (33% by volume) in the mixture was suggested. Lipiodol-ethanol mixtures with reduced ethanol proportions have been shown to be associated with decreased endothelial damage while maintaining effective delivery of the mixtures to tumor vasculature (9). However, the optimal ratio between lipiodol and ethanol that should be used for TEA remains controversial.In the present study, we aimed to determine the efficacy and optimum volume ratio of lipiodol-ethanol mixture in a rabbit VX2 hepatoma model.     

甘氨双唑钠联合同步放化疗治疗Ⅲ期非小细胞肺癌的临床观察

目的观察甘氨双唑钠(希美钠)联合同步放化疗治疗Ⅲ期非小细胞肺癌(NSCLC)的临床疗效及安全性。方法将70例Ⅲ期NSCLC患者按抽签法随机分为观察组(同步放化疗+希美纳)和对照组(同步放化疗),每组35例。对照组采用三维适形放疗(3D-CRT)+化疗,放疗总剂量DT 6 000~7 000 c Gy/30~35F/6~7W;化疗方案为多西他赛+顺铂。观察组在同步放化疗的基础上予希美钠800 mg/m2/次加入100 ml生理盐水中溶解,30 min内经静脉滴注完,在60min内行放疗,每周1、3、5给药,至放疗结束止。结果观察组的总有效率(CR+PR)为88.6%(31/35),CR率为42.9%(15/35);对照组的总有效率(CR+PR)为68.6%(24/35),CR率为20.0%(7/35),两组比较差异均有统计学意义(P<0.05);两组不良反应的发生率比较差异无统计学意义(P>0.05)。观察组在同步放化疗基础上使用希美钠过程中未见神经系统等方面的明显不良反应。结论希美钠联合同步放化疗治疗Ⅲ期NSCLC可提高疗效,未增加不良反应。