On the use of denaturing gradient gel electrophoresis approach for bacterial identification in endodontic infections

Bacteria in infected root canals of teeth evincing chronic apical periodontitis lesions were identified by a polymerase chain reaction–denaturing gradient gel electrophoresis (PCR-DGGE) approach. DNA was extracted from root canal samples, and part of the 16S rRNA gene of all bacteria was amplified by PCR and separated by DGGE, generating banding patterns representative of the community structure. Twenty visible bands were cut out of the gel, re-amplified, and sequenced to provide identification. Sequencing analysis revealed the presence of both cultivable and as-yet-uncultivated species in the samples analyzed, including representatives of the genera Fusobacterium, Bacteroides, Dialister, Synergistes, Prevotella, Eubacterium and Peptostreptococcus. Unambiguous identification was not always possible and the method’s limitations are discussed. In general, the findings showed that PCR-DGGE can be useful for the identification of both cultivable and as-yet-uncultivated bacteria in endodontic infections.     

根尖定位仪测量根尖破坏牙根管长度的准确性研究

目的 比较Root ZX,Propex,Justy Ⅱ和 Raypex5 4种根尖定位仪测量根尖受破坏牙齿工作长度的准确性.方法 将53颗离体牙沿釉牙骨质界截冠、去髓,根管预备到25#,使用Root ZX(A组),Propex(B组),Justy Ⅱ(C组)和 Raypex5(D组) 4种根尖定位仪分别测量每个根管的工作长度;再使用超声倒预备工作尖将以上各牙沿根尖孔破坏根尖狭窄部,再次用4种根尖定位仪测量工作长度.结果 所得数据与解剖镜下测量的实际数据进行比较,根尖完整时A、B、C、D4组数据在-0.5～0.5 mm误差范围内的百分数分别为86.3%、88.8%、85.0%、88.8%.根尖破坏时A、B、C、D4组数据在-0.5～0.5 mm误差范围内的百分数分别为16.7%、20.5%、10.3%、48.7%,在-1～1 mm误差范围内的百分数分别为74.4%、52.6%、57.7%、91.0%.结论 4种根尖定位仪对于根尖破坏的牙齿测量准确性比根尖完整的牙齿要低,相比之下Raypex5的准确性比较高.     

Non-oncotic properties of albumin. A multidisciplinary vision about the implications for critically ill patients

Introduction: Effective resuscitation with human albumin solutions is achieved with less fluid than with crystalloid solutions. However, the role of albumin in today’s critical care unit is also linked to its multiple pharmacological effects.

Areas covered: The potential clinical benefits of albumin in select populations of critically ill patients like sepsis seem related to immunomodulatory and anti-inflammatory effects, antibiotic transportation and endothelial stabilization. Albumin transports many drugs used in critically ill patients. Such binding to albumin is frequently lessened in critically ill patients with hypoalbuminemia. These changes could result in sub-optimal treatment. Albumin has immunomodulatory capacity by binding several bacterial products. Albumin also influences vascular integrity, contributing to the maintenance of the normal capillary permeability. Moreover, the albumin molecule encompasses several antioxidant properties, thereby significantly reducing re-oxygenation injury, which is especially important in sepsis. In fact, most studies of albumin administration are a combination of a degree of resuscitation with a degree of maintenance or supplementation of albumin.

Expert commentary: The potential clinical benefits of the use of albumin in selected critically ill patients such as sepsis seem related to its immunomodulatory and anti-inflammatory effects, antioxidant properties, antibiotic transportation and endothelial stabilization. Additional studies are warranted to further elucidate the underlying physiologic and molecular rationale.     

术中导航校准技术辅助下青少年特发性脊柱侧凸顶椎区置钉精确性研究

【摘要】 目的：比较青少年特发性脊柱侧凸（adolescent idiopathic scoliosis,AIS）顶椎区相同椎弓根类型在导航及导航校准技术辅助下置钉的精确性及偏出方向,并分析影响导航置钉偏移的相关因素及导航校准技术的临床意义。方法：回顾性分析自2017年10月～2020年10月,在我院明确诊断为AIS并在导航辅助下行经后路脊柱侧凸矫形内固定术治疗的41例患者,依据术中是否使用导航校准技术,将41例患者分为两组：导航组（n=22）和校准组（n=19）。收集两组患者基本信息,记录两组患者Risser征,术前、术后Cobb角,术后1年时矫形率,根据付长峰椎弓根分型系统对两组患者顶椎区椎弓根分型（A、B、C、D、E型）,依据Rao分型评估两组相同椎弓根类型的置钉精确性。结果：校准组A、B、C型椎弓根优良置钉率（96.4%、87.8%、84.0%）显著高于导航组（79.2%、70.5%、56.7%）,且凹凸双侧0级钉率显著高于导航组,同时校准组B型椎弓根及其凹凸双侧3级钉率（4.1%、2.0%、6.3%）及C型椎弓根凸侧2级钉置钉率（11.1%）显著低于导航组（12.4%、11.1%、13.7%、50.0%）,两组间差异均具有统计学意义（P＜0.05）。此外,校准组A、B、C型椎弓根外侧皮质破壁率（33.3%、33.3%、60.0%）显著低于导航组（64.0%、38.6%、73.1%）,同时校准组A型椎弓根椎体前壁穿破率（0.0%）及C型椎弓根凹侧外侧皮质破壁率（66.7%）显著低于导航组（24.0%、77.8%）,而B型椎弓根内侧皮质穿破率（41.7%）高于导航组（40.9%）,但其凹侧内侧皮质穿破率（36.4%）显著低于导航组（33.3%）,两组间差异均具有统计学意义（P＜0.05）。两组间均未发生脊髓、神经血管损伤等严重并发症。结论：与传统导航相比,导航校准技术在术中能够有效地预防导航偏移,显著提高AIS顶椎区A、B、C型椎弓根置钉精确性,降低误置螺钉外侧壁穿孔率及B型椎弓根凹侧内侧壁穿孔率,提高手术的安全性。     

左室心尖与心底旋转变化规律的超声研究

目的检测心尖旋转发生变化时心底旋转的变化规律。方法14只杂种犬作为研究对象,用加热的方法破坏心尖部心肌使心尖旋转幅度变小,用超声组织多普勒检测施加条件前、后心尖及心底旋转幅度的变化,并以收缩期旋转的峰值作为比较的参数。用配备了PhilipQLAB高级软件的个人电脑计算心尖及心底旋转幅度。结果心尖部心肌被破坏后心尖旋转幅度明显降低,由8.48°±4.02°降为3.14°±1.35°（P〈0.001）;左室扭转因心尖旋转的明显减低而减低（左室扭转=左室心尖旋转-左室心底旋转）;心底旋转幅度也有一定程度的减低,由2.41°±0.68°减低为1.11°±0.90°（P〈0.001）。结论心尖旋转幅度明显减低时,心底旋转幅度也减低。虽然心底旋转减低并未使左室扭转保持不变,但其部分代偿了左室扭转的降低,这显示了除收缩期左室被破坏心肌以外的其它部位心肌代偿收缩增强的同时左室扭转也有代偿的过程。左室扭转是左室收缩的组成部分,一定程度上反映左室的收缩情况。     

Lessons Learned: Medical and Health Care Management for Emergency Workers at the TEPCO Fukushima Daiichi APP Accident

During the emergency work at the Fukushima Daiichi Atomic Power Plant (APP), the Tokyo Electric Power Company (TEPCO) and the Japanese government experienced various problems in medical and health care management issues, including special medical examinations, on-site triage and initial treatment, patient transportation, lodging and food, and long-term health care for emergency workers. To resolve these problems, the Ministry of Health, Labor and Welfare (MHLW) issued a series of compulsory directives and provided administrative guidance to TEPCO. Based on the experiences and lessons learned, the MHLW recognized that the proper management and implementation of medical and health care management in response to a similar accident would require sufficient measures and systematic preparation, including the following:

1. In case of large-scale nuclear accidents, the government needs to assist in dispatching medical staff to the affected plants.

2. Nuclear facility operators, medical facilities and fire departments should make an agreement to clarify the division of the roles played prior to the accident and should conduct emergency drills periodically with the full attendance of related personnel to identify and resolve the problems.

3. Operators need to develop a support base at a safe distance from the plant and to prepare to develop makeshift lodgings in case of emergency.

4. Operators need to come to an agreement to share food stocks among closely located nuclear plants and prepare cooking equipment that can be used in case of blackout to provide warm foods and drinks to as many workers as possible.

5. It is necessary to conduct long-term follow-up for emergency workers, including health care system, medical examinations and mental health consultations.     

上海市生活垃圾内河集装箱运输优势的探讨

对上海市生活垃圾的运输河道进行水质取样分析,讨论内河集装箱运输模式的优势及其改善水体状况的作用。     

Complications in the clinical course of tako-tsubo cardiomyopathy

Objective

This study evaluated the frequency, severity and outcome of complications in the clinical course of tako-tsubo cardiomyopathy (TTC).

Background

TTC is regarded as a benign disease since left ventricular (LV) function returns to normal within a short time. However, severe complications have been reported in selected patients.

Methods

From 37 hospitals, 209 patients (189 female, age 69 ± 12 years) were prospectively included in a TTC registry.

Results

Complications developed in 108/209 patients (52%); 23 (11%) had > 2 complications. Complications occurred median 1 day after symptom onset, and 77% were seen within 3 days. Arrhythmias were documented in 45/209 patients (22%) including atrial fibrillation in 32 (15%) and ventricular tachycardia in 17 (8%). Of 8 patients resuscitated (4%), 6 survived. Additional complications were right ventricular involvement (24%), pulmonary edema (13%), cardiogenic shock (7%), transient intraventricular pressure gradients (5%), LV thrombi (3%) and stroke (1%). During hospitalization, 5/209 patients (2.5%) died. Patients with complications were older (70 ± 13 vs 67 ± 10 years, p = 0.012), had a higher heart rate (91 ± 26 vs 83 ± 19/min, p = 0.025), more frequently Q\ waves on the admission ECG (36% vs 21%, p = 0.019) and a lower LV ejection fraction (47 ± 15 vs 54 ± 14%, p = 0.002). Multivariate regression analysis identified Q-waves on admission (OR 2.49, 95% CI 1.23–5.05, p = 0.021) and ejection fraction ≤ 30% (OR 4.03, 95% CI 1.04–15.67, p = 0.022) as independent predictors for complications.

Conclusions

TTC may be associated with severe complications in half of the patients. Since the majority of complications occur up to day 3, monitoring is advisable for this time period.     

Anatomic Analysis of Palatal Roots of Maxillary Molars Using Micro–computed Tomography

IntroductionThe morphology of the palatal root of maxillary first and second molars was analyzed and compared using micro–computed tomographic scanning.MethodsForty-seven extracted maxillary molars were scanned with a micro–computed tomographic device to analyze the palatal radicular dentin dimensions, canal working width, root length, canal curvature, lateral canals, and apical constriction anatomy. Quantitative data were analyzed with mean and standard deviation for first and second molars, respectively. Comparison was made between first and second molars using an unpaired t test.ResultsThe palatal root of maxillary first molars was found to have statistically significantly thinner dentin than second molars on the palatal aspect of the root 8–11 mm from the apex, correlating to the coronal and middle thirds of the root. First molar palatal roots also had a statistically significantly wider canal mesiodistally than second molars at 13–15 mm from the apex, correlating approximately to the level of the cementoenamel junction and pulpal floor. Significant canal curvature was present. These findings suggest the need for conservative coronal flaring and instrumentation.ConclusionsThe absence of an apical constriction in 76.6% of the specimens highlights the importance of creating an apical seat through instrumentation to maintain obturation materials. A minimum master apical file size of 40 is recommended based on preoperative working widths in the apical 0.5–1.0 mm. A root-end resection of 3.5 mm would remove a greater majority of lateral canals.