天津地区福氏志贺菌整合子携带及耐药性研究

目的了解天津地区不同年份福氏志贺菌血清型分布,整合子携带情况,耐药性及其变化趋势。方法采用血清学方法对天津地区不同年份分离的56株福氏志贺菌进行分型;PCR扩增整合子整合酶及可变区,并测序;采用K-B法测定其对16种抗菌药物的敏感性。结果 1981~1983年分离株福氏志贺菌1类整合酶阳性率为87.50%(28/32),其中27株可变区含氨基糖苷类药物耐药基因aadA;2009~2011年分离株福氏志贺菌1类整合酶阳性率为91.67%(22/24),可变区及3’末端扩增均阴性。1981~1983年分离株福氏志贺菌2类整合酶均阴性;2009~2011年分离株福氏志贺菌2类整合酶阳性率79.17%(19/24),可变区含dfrA1、sat1、aadA1,介导对甲氧苄啶、链丝菌素和链霉素耐药。有17株福氏志贺菌1、2类整合酶均阳性。1981~1983年分离株福氏志贺菌对四环素、链霉素、氯霉素及甲氧苄啶/磺胺甲噁唑耐药率高,多重耐药率为65.63%;2009~2011年分离株福氏志贺菌对氨苄西林、链霉素、甲氧苄啶/磺胺甲噁唑、哌拉西林和四环素耐药率高,多重耐药率为83.33%。结论 1、2类整合子广泛存在于天津地区福氏志贺菌中,其中1类整合子3’保守末端可能缺失或存在变异。2009~2011年分离株福氏志贺菌对抗菌药物耐药性较1981~1983年分离株增强,多重耐药率增高。福氏志贺菌优势血清型发生转变,血清型分布呈现多样化。     

肠道微生态与人体疾病相关性研究现状

人类肠道有超过百万亿种微生物,其中包括1000余种已知细菌,这些细菌对肠道微生态具有至关重要的作用。根据已知的微生物与体循环的关系,目前广大学者普遍认为肠道微生态的改变与多种疾病的发生有直接联系。通过总结肠道微生态失衡引发的相关性疾病,引起人们重视,并通过挖掘微生态新靶点,达到缓解、治愈相关疾病的目的。     

TWIK1, a unique background channel with variable ion selectivity

TWIK1 belongs to the family of background K(+) channels with two pore domains. In native and transfected cells, TWIK1 is detected mainly in recycling endosomes. In principal cells in the kidney, TWIK1 gene inactivation leads to the loss of a nonselective cationic conductance, an unexpected effect that was attributed to adaptive regulation of other channels. Here, we show that TWIK1 ion selectivity is modulated by extracellular pH. Although TWIK1 is K(+) selective at neutral pH, it becomes permeable to Na(+) at the acidic pH found in endosomes. Selectivity recovery is slow after restoration of a neutral pH. Such hysteresis makes plausible a role of TWIK1 as a background channel in which selectivity and resulting inhibitory or excitatory influences on cell excitability rely on its recycling rate between internal acidic stores and the plasma membrane. TWIK1(-/-) pancreatic β cells are more polarized than control cells, confirming a depolarizing role of TWIK1 in kidney and pancreatic cells.     

漂白剂对复合树脂的影响

临床上常需要对存在复合树脂修复体的牙进行漂白,或者对漂白后的牙进行复合树脂修复。由于漂白剂具有较强的氧化性及反应活性,在一定程度上影响了复合树脂的性能如微硬度、表面粗糙度等;因此,研究漂白剂对复合树脂的影响有重要的临床意义。本文就漂白剂对复合树脂表面性能、与釉质和牙本质粘接强度、微渗漏、颜色等的影响作一综述。     

Metastatic Crohn's disease. Response to adalimumab dose intensification

Inflammatory bowel disease is accompanied by extraintestinal manifestations in a high percentage of patients. Cutaneous lesions are the second most prevalent of these manifestations, and within these, metastatic Crohn's disease is one of the least common, being the least frequent specific cutaneous manifestation of Crohn's disease. This entity includes cutaneous and subcutaneous lesions with a non-caseating granulomatous appearance on histological analysis identical to that of Crohn's disease. These lesions are not found adjacent to the digestive tract. Due to the low prevalence of these manifestations, conclusive trials on the treatment of choice have not been performed and there is no well-defined therapeutic strategy. Distinct therapies with varying results have been reported. We report the case of a female patient with longstanding and complex Crohn's disease who developed metastatic cutaneous manifestations while receiving adalimumab. The cutaneous manifestations responded well to dose intensification of this drug. A review of the literature is provided.     

Effects of Head and Neck Inclination on Bilateral Sternocleidomastoid EMG Activity in Healthy Subjects and in Patients with Myogenic Cranio-Cervical-Mandibular Dysfunction

This study was conducted in order to determine the effect of head and neck position on bilateral electromyographic (EMG) activity of the sternocleidomastoid muscles. The study was performed on 16 patients with myogenic cranio-cervical-mandibular dysfunction (CMD) and 16 healthy subjects. EMG recordings at rest and during swallowing of saliva and maximal voluntary clenching were performed by placing surface electrodes on the right and left sternocleidomastoid muscles. EMG activity was recorded in the left lateral decubitus position, in a darkened room and with the individual's eyes closed, under the following experimental conditions: 1. Head, neck, and body horizontally aligned; 2. Head and neck upwardly inclined with respect to the body, simulating the effect of a thick pillow, 3. Head and neck downwardly inclined with respect to the body, simulating the effect of a thin pillow. Variation of head and neck positions was determined by measuring the distance from the angle of neck and shoulder and the apex of the shoulder (SND = shoulder—neck distance) of each individual. Then, head and neck were forward or downwardly inclined with respect to the body at one-third of SND. A significantly higher contralateral EMG activity and a more asymmetric EMG activity were observed in the CMD group than in the healthy subjects (Kruskal-Wallis Test).These results suggest a different behavior of bilateral sternocleidomastoid EMG activity in CMD patients than in healthy subjects depending on the positioning of the head and neck.     

可注射型热触发仿天然骨材料的基础研究

目的：试图研制可注射型热敏仿天然骨材料,测定其理化特性,并将其初步应用于体外根尖孔破坏的离体牙模型上。方法：采用逆向蒸发法制备载碱性磷酸酶（alkalinephosphatase,ALP）的脂质体,考察其包封率、活性率及相变温度。将载ALP、载钙离子（Ca^24）和磷酸盐（Pi）3种脂质体与β-甘油磷酸盐（β-glycerophosphate,β-GP）混合制备矿化液,观测矿物质的形态、元素分析及红外光谱曲线;将I型胶原与以上矿化液混合制备的复合材料应用于根尖孔破坏的离体牙根尖周围,根管充填并统计分析。结果：载ALP的脂质体平均包封率为25．1％,平均活性率为16．5％,相变温度为37．3～40．1℃,峰值为39．2℃;与未加ALP者相比,所得矿化物形态和Ca／Pi比与天然骨中矿化物更接近,红外光谱曲线表明其为羟基磷灰石;体外模型显示该复合材料可在一定程度上支托根充材料,预防超充。     

Ulnar Nerve Innervation of the Triceps Muscle: Real or Apparent? An Anatomic Study

Background

Since the 18th century, the existence of ulnar nerve innervation of the medial head of the triceps brachii muscle has been controversial. The evidence for or against such innervation has been based on macroscopic dissection, an unsuitable method for studying intraneural topography or intramuscular branching. The study of smaller specimens (embryos or fetuses) by means of serial histologic sections may resolve the controversy.

Questions/Purposes

Using fetal specimens and histology we determined the contributions of the ulnar and radial nerves to innervation of the triceps brachii muscle.

Methods

We histologically examined 15 embryonic and fetal arms. Radial nerve branches obtained from six adult arms were analyzed immunohistochemically to determine motor fiber content.

Results

The medial head of the triceps brachii muscle was always innervated by the radial nerve (ulnar collateral branch). The branches seeming to leave the ulnar nerve at elbow level were the continuation of the radial nerve that had joined the ulnar nerve sheath via a connection in the axillary region. Immunohistochemistry revealed motor and nonmotor fibers in this radial nerve branch.

Conclusions

A connection between the radial and ulnar nerves sometimes may exist, resulting in an apparent ulnar nerve origin of muscular branches to the medial head of the triceps, even though in all our specimens the fibers could be traced back to the radial nerve.

Clinical Relevance

Before performing or suggesting new muscle and nerve transpositions using this apparent ulnar innervation, the real origin should be confirmed to avoid failure.