Effects of local anaesthetics (lidocaine) on the structure and function of ciliated respiratory epithelial cells

Summary— Sampling for nasal or bronchial ciliated cells requires the use of anaesthetic agents, but such drugs may interfere with the morphological or functional results. Lidocaine is the most frequently used local anaesthetic. In order to study the morphological and functional effects of lidocaine hydrochloride, we designed an experimental study on ciliated cells from guinea pig and bovine trachea. On guinea pig tracheal specimens, different lidocaine concentrations (0.05, 0.25 and 1%) were tested. Tracheal rings were immersed in either culture medium alone (control) or in different lidocaine concentrations. Measurements of ciliary beat frequency (CBF) were performed by the stroboscopic method. Tracheal rings were consecutively incubated in culture medium alone and a second set of measurements was performed. Tracheal rings were studied by light microscopy after incubation in either 1% lidocaine or in culture medium alone. On bovine tracheal specimens, a coton wool swab impregnated with different lidocaine concentrations (0, 0.25, 1, 2.5 and 5%) was placed in contact with the tracheal mucosa. Three different kinds of samples were collected: the first one was used to study CBF, the second one (0.1 and 5%) was studied by scanning electron microscope (SEM) and the third (0.1 and 5%) by transmission electron microscopy (TEM). The results on guinea pig specimens show a significant but reversible CBF diminution for concentrations of 0.25 and 1% lidocaine and cellular lesions for the concentration of 1%. On bovine specimens a diminution in CBF for concentrations of 2.5 and 5% lidocaine was shown and the SEM study demonstrated obvious lesions on the epithelial surface treated with the 5% concentration. The TEM study showed morphological alterations on respiratory epithelium (deciliated areas, cytoplasmic vacuoles and mitochondrial swelling) for 5% lidocaine concentration. However the axonemal structure of cilia was normal for control and 5% concentration. We concluded that in vitro lidocaine can inhibit the CBF and that high concentrations of lidocaine can damage the respiratory epithelium but without modifications of the axonemal ultrastructure.     

The Bite of the Honeybee: 2-Heptanone Secreted from Honeybee Mandibles during a Bite Acts as a Local Anaesthetic in Insects and Mammals

Honeybees secrete 2-heptanone (2-H) from their mandibular glands when they bite. Researchers have identified several possible functions: 2-H could act as an alarm pheromone to recruit guards and soldiers, it could act as a chemical marker, or it could have some other function. The actual role of 2-H in honeybee behaviour remains unresolved. In this study, we show that 2-H acts as an anaesthetic in small arthropods, such as wax moth larva (WML) and Varroa mites, which are paralysed after a honeybee bite. We demonstrated that honeybee mandibles can penetrate the cuticle of WML, introducing less than one nanolitre of 2-H into the WML open circulatory system and causing instantaneous anaesthetization that lasts for a few minutes. The first indication that 2-H acts as a local anaesthetic was that its effect on larval response, inhibition and recovery is very similar to that of lidocaine. We compared the inhibitory effects of 2-H and lidocaine on voltage-gated sodium channels. Although both compounds blocked the hNav1.6 and hNav1.2 channels, lidocaine was slightly more effective, 2.82 times, on hNav.6. In contrast, when the two compounds were tested using an ex vivo preparation–the isolated rat sciatic nerve–the function of the two compounds was so similar that we were able to definitively classify 2-H as a local anaesthetic. Using the same method, we showed that 2-H has the fastest inhibitory effect of all alkyl-ketones tested, including the isomers 3- and 4-heptanone. This suggests that natural selection may have favoured 2-H over other, similar compounds because of the associated fitness advantages it confers. Our results reveal a previously unknown role of 2-H in honeybee defensive behaviour and due to its minor neurotoxicity show potential for developing a new local anaesthetic from a natural product, which could be used in human and veterinary medicine.     

Correlation of bacterial hyperthermic survival with anaesthetic potency

We have evaluated several local anaesthetics and hypnotics for their relative ability to influence hyperthermic cell killing. Bacterial cell survival following exposure to heat and anaesthetic was used as the assay system. The E. coli bacterium used was the unsaturated fatty acid auxotroph, K1060. It was grown at 37 degrees C in medium supplemented with oleic acid and then exposed to 47 degrees C hyperthermia in the presence of an anaesthetic. The local anaesthetics tested were procaine, lidocaine, tetracaine, and benzocaine, and the general anaesthetics were barbital and pentobarbital. The dose response for each anaesthetic was determined over a five-hour heating period. The anaesthetic concentration required during heating to halve the time for cell killing found with heat alone is 5.9 mM for procaine, 0.8 mM for lidocaine, 0.12 mM for tetracaine, 2.0 mM for benzocaine, 6.7 mM for barbital and 1.2 mM for pentobarbital. There is a direct correlation between equivalent effect doses of the local anaesthetics and published data for the relative potency of the same anaesthetics as determined by respiratory arrest in mice and by myocardial contractile force in dogs. The assay we have described would be a convenient and easy test for the interaction of these drugs with hyperthermia. The use of this interaction with hyperthermia as an adjuvant in combined radiation-hyperthermia therapy should be tested.     

Local anaesthetic block protects against electrically-induced damage in peripheral nerve

This study is one of a series addressing the mechanisms involved in the production of neural damage caused by continuous, prolonged electrical stimulation of peripheral nerve. It has been previously shown that sustained, high frequency electrical stimulation of the cat's peroneal nerve may cause irreversible neural damage in the form of axonal degeneration of the large myelinated fibres. In this study we demonstrate that blocking the action potentials on most of the nerve fibres with local anaesthetics (10% procaine or 2% lidocaine) almost completely prevents the axonal degeneration. The abolition of axonal injury by local anaesthetic block strongly suggests that the electrically-induced damage is due to prolonged electrical excitation of axons. Furthermore, since less than complete suppression of the induced neural activity by local anaesthetic engenders essentially complete sparing of all axons, our results suggest that the damage to individual axons derives, at least in part, from stimulation-induced global changes in the nerve.     

Bronchial epithelial cells release IL-6, CXCL1 and CXCL8 upon mast cell interaction

Although mast cells have been found in increased numbers in bronchial epithelium in asthma patients, the pathogenic role of the interaction of mast cells with bronchial epithelial cells in the development of local inflammation in asthma is not well understood. In this study, primary human bronchial epithelial cells and a human mast cell line (HMC-1) were cultured either together or separately in the presence or absence of various signaling molecule inhibitors or dexamethasone. Cytokine IL-6, and chemokines including CXCL1 and CXCL8 in cell culture supernatant were assayed by enzyme-linked immunosorbent assay (ELISA), and the activity of mitogen-activated protein kinases (MAPKs), or nuclear factor-κB (NF-κB) in co-culture system was analyzed by ELISA. Co-culture of bronchial epithelial cells and mast cells induced a significant elevation of IL-6, CXCL1 and CXCL8 in bronchial epithelial cells, and both IL-17A and IL-17F could further enhance the release of these inflammatory mediators from co-culture. The induction of IL-6, CXCL1 and CXCL8 upon the interaction of bronchial epithelial cells with mast cells was mediated by MAPKs and NF-κB signaling pathways. These data indicate that the interaction of mast cells with bronchial epithelial cells may represent a crucial mechanism of regulating local inflammatory response in allergic asthma.     

Effect of Metal Ions on Melanin – Local Anaesthetic Drug Complexes

The affinity of melanin biopolymers for metal ions, drugs and other organic compounds is an important factor in the etiology of toxic retinopathy, hiperpigmentation, otic lesions and irreversible extrapyramidal disorders. The aim of the presented work was to examine the interaction of local anaesthetic drugs used in ophthalmology with model DOPA-melanin in the presence of metal ions. It has been demonstrated that the analyzed drugs form complexes with melanin biopolymer. Based on the .values of association constants,, the following order of drugs affinity to melanin was found: tetracaine > procaine >> bupivacaine > lidocaine. It has also been shown that Cu²⁺ and Zn²⁺ ions administered to DOPA-melanin before complexing with drugs decrease the total amount of local anaesthetics bound to melanin. The blocking of some active centers in melanin molecules by metal ions, which potentially exist in living systems, may change the clinical therapeutic efficiency of the analyzed local anaesthetic drugs.     

Multiple inhibitory actions of lidocaine on Torpedo nicotinic acetylcholine receptors transplanted to Xenopus oocytes

Lidocaine is a local anaesthetic that blocks sodium channels, but also inhibits several ligand-gated ion-channels. The aim of this work was to unravel the mechanisms by which lidocaine blocks Torpedo nicotinic receptors transplanted to Xenopus oocytes. Acetylcholine-elicited currents were reversibly blocked by lidocaine, in a concentration dependent manner. At doses lower than the IC(50) , lidocaine blocked nicotinic receptors only at negative potentials, indicating an open-channel blockade; the binding site within the channel was at about 30% of the way through the electrical field across the membrane. In the presence of higher lidocaine doses, nicotinic receptors were blocked both at positive and negative potentials, acetylcholine dose-response curve shifted to the right and lidocaine pre-application, before its co-application with acetylcholine, enhanced the current inhibition, indicating all together that lidocaine also blocked resting receptors; besides, it increased the current decay rate. When lidocaine, at low doses, was co-applied with 2-(triethylammonio)-N-(2,6-dimethylphenyl) acetamide bromide, edrophonium or 1,5-bis(4-allyldimethylammoniumphenyl)pentan-3-one dibromide, which are quaternary-ammonium molecules that also blocked nicotinic receptors, there was an additive inhibitory effect, indicating that these molecules bound to different sites within the channel pore. These results prove that lidocaine blocks nicotinic receptors by several independent mechanisms and evidence the diverse and complex modulation of this receptor by structurally related molecules.     

喘息的"度"与支气管哮喘阶梯治疗

目的:探讨掌握喘息"度"与支气管哮喘阶梯治疗的关系。方法:充分掌握支气管哮喘分级治疗方案和支气管哮喘病情,将喘息"度"细致化,与分级治疗用药"度"密切结合起来,对于完全理想的控制哮喘将会起到极大的指导作用,对于升阶梯和降阶梯治疗都会起到重要而细致的指导作用。必须将平喘治疗措施置于患者全身病情变化及总体治疗之下,会取得更加理想的哮喘控制效果。而强化支气管哮喘患者教育在支气管哮喘理想治疗中占据极为重要的地位,甚至直接关系到哮喘控制的持久性和稳定性。应得到高度重视。结果:喘息"度"与支气管哮喘的发作程度密切相关,准确把握并分级十分重要。结论:准确把握喘息"度"并与支气管哮喘分级治疗方法结合,将对稳定平息支气管哮喘起到意想不到的效果。     

2007～2011年鄂州市气传致敏真菌调查及其与支气管哮喘的相关性

目的 探讨2007年5月～ 2011年4月鄂州市气传致敏真菌和支气管哮喘关系,以了解该地区支气管哮喘情况.方法 运用暴片调查法和暴皿调查法统计和记录鄂州市气传致敏真菌的种类及数量.选择该时期内鄂州市100例支气管哮喘患者采用真菌变应原浸液作过敏原皮试发现有35例患者皮内试验阳性,将35例发作期患者和40例稳定期支气管哮喘患者行曲霉特异性IgE测定.结果 100例支气管哮喘患者皮内实验组阳性35例,阳性率为35％,而在35例患者中IgE阳性有31例,检测符合率为88.58％,稳定期患者中阳性反应例数2例,阳性率为5％,两组阳性率比较差异具有显著性（P＜0.05）.结论 鄂州市气传致敏真菌和支气管哮喘密切相关,主要致病菌为曲霉,是支气管哮喘的致敏原之一,需要注意环境卫生以减少气传致敏真菌的数量.     

II - Prostaglandin hyperalgesia: the peripheral analgesic activity of morphine, enkephalins and opioid antagonists.

Morphine, enkephalins, nalorphine, naloxone and pentazocine are shown to have a peripheral analgesic effect. In our modification of the Randall-Selitto test these substances were 50--100 times more potent than a standard local anaesthetic, lidocaine. At this peripheral site, naloxone did not antagonize the effect of morphine. Morphine had a marked analgesic effect on the hyperalgesia induced by PGE2 and PGI2, BaCl2, Ca2+ ionophore A23187, isoprenaline but not on that induced by dibutyryl cyclic AMP. It was suggested that the peripheral analgesic effect of morphine is due to an inhibition of adenylate-cyclase activity.     

Acute effects of intratracheal administration of platelet-activating factor in baboons

The bronchomotor effect of intratracheal administration of PAF-acether (60 micrograms X kg -1) was investigated in 37 curarized baboons mechanically ventilated with constant volume and frequency. PAF-acether caused an immediate bronchoconstriction as assessed by a marked increase in peak inspiratory pressure with no change in static pulmonary compliance and chest X-rays. There was a concomitant fall in arterial PO2 and a significant increase in ventilated unperfused lung zones. A decrease of circulating platelets and leucocytes was also observed. Local anesthesia with lidocaine and atropine did not prevent PAF-acether-induced bronchoconstriction although both markedly reduced the bronchial response to histamine. Albuterol significantly reduced the bronchial response to PAF-acether. Pretreatment with aspirin (80 mg X kg -1 iv) did not prevent the bronchoconstriction caused by PAF-acether, and intravenous or intratracheal arachidonic acid caused no bronchial response. Thus the role of cyclooxygenase metabolites of arachidonic acid in PAF-acether-induced bronchoconstriction is unlikely. In conclusion, an acute bronchoconstriction probably not triggered by stimulation of irritant receptors of the airways and associated with aggregation of platelet takes place subsequent to intratracheal administration of PAF-acether. These data suggest that PAF-acether might play a role in the pathogenesis of human asthma.     

支气管哮喘患儿病情控制的影响因素及其家长知信行问卷调查分析

摘要 目的：调查支气管哮喘患儿家长知信行情况,并分析支气管哮喘患儿病情控制的影响因素。方法：于2016年7月~2020年7月期间,选取我院收治的500例支气管哮喘患儿及其家长作为研究对象。患儿家长知信行情况采用《哮喘患儿家长知信行问卷》调查。患儿近4周的病情控制水平参照《诸福棠实用儿科学(第8版)》中的相关标准进行确定,病情控制水平包括良好控制、部分控制和未控制。将良好控制、部分控制的患儿纳为哮喘控制组,将未控制的患儿纳为哮喘未控制组。采用本院自制的调查量表调查患儿及其家长的信息,分析支气管哮喘患儿病情控制的影响因素。结果：支气管哮喘儿童家长知信行情况不容乐观。支气管哮喘患儿病情控制率为38.06%（187/491）。单因素分析结果表明,支气管哮喘患儿病情控制与家庭人均月收入、患儿个人过敏史、家长受教育程度、哮喘家族史、是否坚持长期用药、是否定期复诊有关（P<0.05）。多因素Logistic回归分析结果显示,家长受教育程度、家庭人均月收入、患儿个人过敏史、哮喘家族史、是否坚持长期用药、是否定期复诊均是支气管哮喘患儿病情控制的影响因素（P<0.05）。结论：本研究中支气管哮喘患儿病情控制水平一般,且支气管哮喘儿童家长知信行情况不容乐观,其中家长受教育程度、家庭人均月收入、患儿个人过敏史等均是支气管哮喘患儿病情控制的影响因素,临床中应结合相关因素进行针对性的干预或治疗,以期实现对支气管哮喘患儿病情的良好控制。     

Genome-wide association study of bronchial asthma in the Volga-Ural region of Russia

Bronchial asthma is a chronic inflammatory respiratory disease that is caused by the complex interaction of environmental influences and genetic susceptibility. The first genome-wide association study of bronchial asthma discovered a significant association between SNPs within 17q12-21 genomic region and childhood bronchial asthma in individuals of European descent. Association with this genomic region was then replicated in a number of independent samples of European and Asian descent. Here we report results of the first genome-wide association study of bronchial asthma in the Volga-Ural region of Russia. The present study includes 358 unrelated patients with physician-diagnosed bronchial asthma and 369 disease-free control subjects of different ethnic origin (Russians, Tatars and Bashkirs). Genotyping of DNA samples was carried out using the Illumina Human610 quad array as a part of GABRIEL project (contract from the EC No LSHB-CT-2006-018996). After QC filtering procedures, a final set of 550915 SNPs genotyped in 330 cases and 348 controls was tested for association with bronchial asthma. Five markers on chromosome 17q12-21 showed statistically significant association with bronchial asthma (p < or = 4.79 x 10(-7)). SNP rs7216389 with the strongest evidence for association (p = 1.01 x 10(-7)) is located within the first intron of the GSDMB gene. Evidence for association was stronger with childhood-onset asthma (p = 1.97 x 10(-6) for SNP rs7216389) compared to late-onset asthma (p = 1.8 x 10(-4) for SNP rs7216389). Our replication study using three SNPs within GSDMB gene confirmed association with only childhood-onset asthma. In summary, these results suggest an important role for genetic variants within 17q12-q21 region in the development of bronchial asthma in the Volga-Ural region of Russia.     

Nociception after intraperitoneal injection of a sodium pentobarbitone formulation with and without lidocaine in rats quantified by expression of neuronal c-fos in the spinal cord--a preliminary study

After a search on Medline, it appears that intraperitoneal injection of sodium pentobarbitone is often used for anaesthesia and euthanasia of rodents. In the present pilot study in rats, spinal nociception after intraperitoneal injection of sodium pentobarbitone, with and without lidocaine, was examined by estimation of the number of c-fos-expressing neurones in the spinal dorsal horn. One group of rats received an intraperitoneal injection of 0.4 mL/kg sodium pentobarbitone (100 mg/mL; n=4). Another group of rats received a similar intraperitoneal injection of sodium pentobarbitone formulated with lidocaine 10 mg/mL (n=4); a control group received a similar intraperitoneal injection of 0.9% saline (n=4). After 3 h, the animals were re-anaesthetized and perfused with 4% formaldehyde, and the spinal cord was collected and processed by immunohistochemistry for stereological quantification of the number of neurones with c-fos-like immunoreactivity (FLI). Intraperitoneal injection of the sodium pentobarbitone formulation caused a significantly increased number of neurones with FLI in the spinal cord (3930+/-247; mean+/-SEM; P<0.001) compared with the saline control group (765+/-131). The lidocaine added to the sodium pentobarbitone formulation significantly reduced the number to 2716+/-393 (P<0.05). In conclusion, intraperitoneal injection of sodium pentobarbitone caused a significant increase in nociception which was lowered by adding lidocaine to the formulation, although it was still significantly higher than the control level. Further studies are needed with the aim of optimizing the lidocaine concentration and also to examine the effect of the combination of lidocaine with a long-acting local anaesthetic agent, e.g. bupivacaine.     

支气管哮喘患者疾病认知状况调查及控制水平的影响因素分析

目的:调查支气管哮喘患者疾病认知状况,并分析控制水平的影响因素。方法:选取2018年7月~2020年7月期间贵州医科大学附属医院诊治的支气管哮喘患者100例,采用面对面问卷调查的方式调查所有患者疾病认知状况。采用哮喘控制测试(ACT)对患者哮喘控制水平进行评估。根据ACT结果将患者分为哮喘未控制组(n=57)和哮喘控制组(n=43)。分析哮喘控制水平的影响因素。结果:支气管哮喘患者对疾病认知相关问题的回答正确率均在60%以上,但仅有12%的患者使用过峰流速仪。本研究中100例患者均完成ACT,其中完全控制17例,控制良好26例,未控制57例,分别占比17.00%、26.00%、57.00%,哮喘控制率为43.00%。由单因素分析显示,支气管哮喘患者的哮喘控制水平与性别、家庭月收入、文化程度、家族史、吸烟史、居住处是否空气污染、病程、哮喘用药依从性、使用吸入性糖皮质激素治疗、抑郁情况、焦虑情况有关(P<0.05)。多因素Logistic回归分析显示:焦虑情况、抑郁情况、居住处空气污染、吸烟史是支气管哮喘患者哮喘控制水平的危险因素,而哮喘用药依从性、使用吸入性糖皮质激素治疗是支气管哮喘患者哮喘控制水平的保护因素(P<0.05)。结论:支气管哮喘患者对疾病有一定的正确认知,但仍未达到理想状态。哮喘控制水平受多种因素影响,可根据相关影响因素做出针对性的干预措施,以改善支气管哮喘控制水平。     

家族性支气管哮喘的遗传方式分析

为研究家族性支气管哮喘的遗传方式, 进一步确定在群体中的传递规律,用群体研究法调查邯郸地区有家族史的支气管哮喘家系。采用家系分析法和Smith无偏差校正法, 进行理论值与观察值符合程度的卡方检验分析。72个家族性支气管哮喘的家系, 包括109个核心家系, 其亲属的患病率为0.46。分析结果表明, 有单基因遗传的倾向。用家系法分析, 符合常染色体显性遗传。对D-× dd婚配家系用Smith法分析, χ² = 3.181, P > 0.05, 所得结果支持常染色体显性遗传(Autosomal domiant inheritance, AD), 并提示不同的婚 配类型, 遗传方式可能不同, 存在着遗传异质性, 研究结果可为家族性支气管哮喘的预防、诊断和治疗提供参考依据。     

The influence of the bronchodilatation test on the duration of forced expiratory tracheal noises in young men

The diagnostic efficiency of estimating the duration of forced expiratory noises under the conditions of bronchial obstruction has been shown. The objective of this study was to analyze the response of the forced expiratory noise duration to the bronchodilatation test with the β₂-agonist in the age- and genderhomogenous group of healthy volunteers and bronchial asthma patients selected as a model of variable bronchial obstruction. Two hundred and sixty young men (16–25 years old) were examined. It was shown that the prevailing type of response in bronchial asthma patients with spirometry confirmed bronchial obstruction was shortened forced expiratory noises. Furthermore, the degree of the shortening considerably depended on the severity of the background bronchial obstruction. The absence of a statistically significant response of the forced expiratory noise duration dominated among healthy volunteers (nonsmokers as well as smokers) and bronchial asthma patients without a spirometry confirmed bronchial obstruction. However, the shortened response occurred much more frequently in bronchial asthma patients than in healthy volunteers. The high specificity (86%) of the response as shortened forced expiratory noises to the β₂-agonist may be useful for diagnostics.     

Establishment of preliminary regulatory network of TRPV1 and related cytokines

Our purpose was to investigate the regulatory mechanism of TRPV1 and related cytokines on children bronchial asthma. TRPV1 mRNA level and two SNP genotypes of children in case group and control group were detected by real-time quantitative PCR. Western blot and ELISA were used to measure the levels of cytokines like IgE, IL-2, etc. Their correlations were analyzed by Logistic regression and KEGG analysis. Moreover, tertiary structure of protein and miRNA binding sites were also predicted by online tools. Case group was obviously different from control group in TRPV1 mRNA level, the two SNP genotypes distribution and the related cytokines levels. Logistic regression analysis further demonstrated that TRPV1 mRNA level, EOS, IL-4 and IL-5 may be risk factors for children bronchial asthma. And based on that, the preliminary regulatory network of children bronchial asthma was drawn. What’s more, mutation of rs4790521 and rs4790522 in TRPV1 gene both induced its corresponding miRNA binding site’s change. The preliminary regulatory network of TRPV1 and related cytokines on children bronchial asthma established in this study provides certain theoretical basis for pathogenesis and treatment of children bronchial asthma.     

BRONCHIAL ASTHMA—Patterns of Morbidity and Mortality in the United States, 1951-1959

On a nationwide basis, bronchial asthma occurs at the rate of 23 cases per 1,000 population. Young males develop bronchial asthma more readily and more severely than young females. Males dying from asthma outnumber females 2 to 1.Eight per cent of the asthmatic persons in the United States have not sought medical attention for this condition. Repeated attacks of severe bronchial asthma increase the likelihood of premature death.Approximately 6,000 deaths due to asthma occur annually in the United States, with a seasonal increase during the winter months. The estimated fatality rate of asthma in the general population is 1.5 deaths per 1,000 asthmatics.