Ciliary central microtubular orientation is of no clinical significance in bronchiectasis

It has been suggested that patients with bronchiectasis might have increased central microtubular orientation angle (CMOA), which leads to poor coordination of ciliary beating, and consequently impairment of airway defence. We have employed transmission electron microscopy to assess CMOA of ciliated nasal mucosa in a cohort of 133 (81F, 56.8+/-16.1yr) stable bronchiectasis and 59 healthy subjects (30F, 49.3+/-22.1yr). There was no significant difference in CMOA between bronchiectasis (13.2 degree) and control subjects (13.0 degree, P=0.82). There was no significant difference in CMOA among patients according to the etiology of bronchiectasis, presence of nasal symptoms, or sputum status of Pseudomonas aeruginosa infection. Patients with more severe bronchiectasis, i.e. those with FEV(1) <60%, FVC <60%, or more than 4 bronchiectatic lung lobes, had significantly lower CMOA than their counterparts (P<0.05). There was no correlation between CMOA with age, 24h sputum volume, exacerbation frequency, FEV(1), FVC, or the number of bronchiectatic lung lobes (P>0.05). CMOA correlated with ciliary beat frequency (negative), and the percent of cilia showing ultrastructural or microtubular defects (P<0.05). Central microtubular orientation angle does not correlate with clinically important parameters, in contrary to the results reported by previously published smaller scale studies.     

Elevated levels of transforming growth factor-beta(1) in serum of patients with stable bronchiectasis

Bronchiectasis is a chronic inflammatory and infective airway disease characterized by irreversible dilatation of the bronchi and persistent purulent sputum. Transforming growth factor-beta(1) (TGF-beta(1)) has been found to be increased in the lungs or bronchoalveolar lavage fluid of patients with inflammatory lung diseases. However, little is known on the serum TGF-beta(1) levels in patients with bronchiectasis. We aimed to determine the serum TGF-beta(1) concentrations in 95 patients with stable bronchiectasis (63 women; mean+/-sd age, 58.9+/-14.1 years) and 68 control subjects (23 women; 48.9+/-12.8 years) by ELISA, and to correlate with clinical parameters. The serum TGF-beta(1) levels were significantly higher in bronchiectatic patients compared with control subjects (median [range], 1812.5 pg/ml [1226.4-4114.5 pg/ml] vs. 1342.4 pg/ml [940.3-2371.7 pg/ml]; P<0.001). There was, however, no correlation between serum TGF-beta(1) levels with FEV(1) (% predicted), FVC (% predicted), 24h sputum volume, the number of bronchiectatic lung lobes or total white blood cell count (P>0.05). Our findings support previous indications that TGF-beta(1) may contribute to bronchiectatic airway inflammation. Further studies on the potential mechanisms and pathogenesis implications of this elevation should also be pursued in future.     

腭胚间充质细胞增殖变化在腭裂形成中的意义

腭胚间充质 (ｅｍｂｒｙｏｎｉｃｐａｌａｔａｌｎｅｓｅｎｃｈｙｍｅ ,ＥＰＭ)细胞的增殖与腭裂的发生密切相关。胚胎早期的腭胚间充质不同程度表达各种生长因子 ,表现出ＥＰＭ细胞的增殖活跃。我们利用维甲酸 (ｒｅｔｉｎｏｉｃａｃｉｄ ,ＲＡ)诱导建立的小鼠腭裂模型 ,检测腭裂发生中ＥＰＭ细胞增殖的变化并探讨其意义。1 材料与方法 :Ｃ5 7ＢＬ/6Ｎ系 2 4只妊娠 10ｄ的孕鼠随机分为实验组和对照组。实验组管饲维甲酸 (按 80ｍｇ/ｋｇ体重) ,对照组管饲等体积的植物油。妊娠 13ｄ第 14ｈ即ＧＤ1314 (ｇｅｓｔａｔｉｏｎｄａｙ ,ＧＤ ,以下类同 ) ,ＧＤ132 2 ,ＧＤ148,ＧＤ1414 ,ＧＤ142 2 ,ＧＤ15 8,ＧＤ15 2 2 ,ＧＤ16 88个时间点分别脱颈处死动物 ,取胚鼠头部 ,包埋连续切片。行免疫组织化学处理 ,ＴＵＮＥＬ染色及图像分析。2 结果 :按腭突的正常生长形态将腭突发育分为垂直生长期 (ＧＤ1314 ～ＧＤ148)、上抬期 (ＧＤ1414 ～ＧＤ15 8)、融合期(ＧＤ15 2 2 ～ＧＤ16 8) ,分别观察比较。对照组增殖细胞核抗原(ＰＣＮＡ)、细胞周期蛋白...     

小鼠颅神经嵴细胞的培养和特征

目的：在体外原代培养Balb/c小鼠胚胎的颅神经嵴细胞。为颅面部各种组织细胞的发育研究提供细胞来源。方法：采用胰酶消化法分离小鼠胚胎第8.5天的颅神经管，从小鼠颅神经管中游离出来的细胞即为颅神经嵴细胞，用免疫组织化学方法鉴定细胞的来源，并测定细胞的生长曲线。结果：成功地培养出小鼠的颅神经嵴细胞，其形态类似成纤维样细胞，免疫组化检测结果表明，神经特异性烯醇化酶（NSE）抗体染色结果阳性。细胞的群体倍增时间为43.65h。结论：原代培养的小鼠颅神经嵴细胞生长稳定，来源明确，是颅面部各种细胞的发育和分化研究中一种有用的工具。     

Effects of erythromycin on Pseudomonas aeruginosa adherence to collagen and morphology in vitro.

The airways of patients with bronchiectasis and cystic fibrosis are often chronically colonised by Pseudomonas aeruginosa (PA), which is virtually impossible to eradicate. Low-dose erythromycin (EM), for unknown mechanisms, is efficacious in bronchiectasis and diffuse panbronchiolitis. In this study, an in vitro model to investigate PA adherence to human type IV basement collagen was developed by using scanning electron microscopy (SEM). There were significantly less PA bacilli per 20 random SEM fields (4,000x) when PA was cultured in 0.05, 0.5 and 5 microg x mL(-1) of EM compared with control (absence of EM). Adherence density (20 SEM fields x log(-1) inocular size) for PA obtained from no EM (56.8 +/- 43.16) was significantly higher than that obtained from 0.05, 0.5, and 5 microg x mL(-1) EM (21.5 +/- 17.56, 23.3 +/- 16.65, and 21.4 +/- 12.65 respectively). By using SEM it was found that PA, when incubated in EM (0.05, 0.5, 5 microg x mL(-1)) had a significant reduction in its diagonal length, radius, height, volume and surface area. It is possible, therefore, that these misshaped Pseudomonas aeruginosa bacilli are more susceptible to host defence mechanisms, while at the same time less adherent to the basement membrane of the airway in vivo. Therefore, this could help explain the clinical efficacy of low-dose erythromycin therapy on patients with Pseudomonas aeoruginosa infection.     

Melatonin enhances the hypoxic response of rat carotid body chemoreceptor

Melatonin attenuates carotid chemoreceptor response to hypercapnic acidosis and may contribute to the effect of circadian rhythms on the chemoreflex. The purpose of this study was to test the hypothesis that melatonin modulates rat carotid chemoreceptor response to hypoxia. To examine the effect of melatonin on the hypoxic response of the chemosensitive cells, cytosolic calcium ([Ca2+]i) was measured by spectrofluorometry in fura-2-loaded type-I (glomus) cells dissociated from rat carotid bodies. Melatonin (0.01-10 nm) did not change the resting Ca2+]i level of the glomus cells but it concentration-dependently increased peak Ca2+]i response to cyanide or deoxygenated buffer. An agonist of melatonin receptors, iodomelatonin also enhanced the Ca2+]i response to hypoxia. The melatonin-induced enhancement of the Ca2+]i response was abolished by pretreatment with nonselective mt1/MT2 antagonist, luzindole, and by MT2 antagonists, 4-phenyl-2-propionamidotetraline or DH97. These findings suggest that melatonin receptors in the glomus cells mediate the effect of melatonin on the chemoreceptor response to hypoxia. In addition, melatonin increased the carotid afferent response to hypoxia in unitary activities recorded from the sinus nerve in isolated carotid bodies superfused with bicarbonate-buffer saline. Furthermore, plethysmographic measurement of ventilatory activities in unanesthetized rats revealed that melatonin (1 mg/kg, i.p.) increased the ventilatory response to hypoxia. Hence, the circadian rhythm of melatonin in arterial blood can modulate the carotid chemoreceptor response to hypoxia. This modulation may be a physiological mechanism involved in the day-light differences in ventilatory activities.     

A quantitative investigation of immunocytochemically stained blood vessels in normal,benign, premalignant and malignant human oral cheek epithelium

The present study was designed to determine whether increased vascularity occurs during malignant transformation of human oral cheek epithelium. Nine normal (N) samples were taken from the resection margins of benign lesions; the pathological lesions were classified as chronic inflammation (CI; n=11), fibrous hyperplasia (FH; n=12), lichen planus (LIP; n=8), dysplasia (DYS; n=5), squamous cell carcinoma (SCC; n=25; well differentiated [SCCWD]; n=10; moderately to poorly differentiated [SCCMPD]; n=15) and epithelium adjacent to carcinomas (EAC; n=6). Sections were stained with monoclonal antibody (mAb) against vimentin using an ABC immunoperoxidase technique. All blood vessels present within a depth of 0.9 mm of lamina propria were quantified irrespective of their morphology. The blood vessel parameters quantified were volume density (V_{VBV, CT}), number per unit area (N_{ABV, CT}), length per unit volume (L_{VBV, CT}) and mean transverse sectional area (A_BV). V_{VBV, CT} increased significantly between normal and all pathological groups. Amongst the pathological groups, statistical differences were detected between CI and SCC, CI and EAC, FH and SCCWD, FH and EAC, LIP and SCC, LIP and EAC, DYS and SCCWD and DYS and EAC. The EAC group had the highest V_{VBV, CT} and the values of N_{ABV, CT} and L_{VBV, CT} were significantly higher in all the pathological groups when compared with the normal group. No significant differences were detected between any of the pathological group. The parameter A_BV increased significantly between normal and DYS, FH, SCC, EAC, FH and EAC, FH and SCC, CI and EAC, CI and SCC, LIP and EAC and LIP and SCC. Spearman rank correlations detected a positive correlation between the severity of oral lesions and all of the blood vessel parameters. We conclude that a mAb against vimentin improved the identification of smaller blood vessels and the blood vessel data suggest that angiogenesis occurs in premalignant and malignant lesions of human oral cheek epithelium. Angiogenesis seems to play an essential role in sustaining the actively growing and transforming cells.     

Endothelial nitric oxide synthase is a critical factor in experimental liver fibrosis

Reduced expression of endothelial nitric oxide synthase (eNOS) in chronic liver disease can reduce hepatic perfusion and accelerate fibrosis. The relationship between eNOS expression and liver fibrogenesis remains unclear. We investigated whether l -arginine attenuated chronic liver fibrosis through eNOS expression. Chronic liver injury was induced by administration of carbon tetrachloride (CCl₄) to mice for 8 weeks. 5-Methylisothiourea hemisulphate (SMT), an iNOS inhibitor, or l -arginine, a NOS substrate were injected subcutaneously. CCl₄-induced hepatotoxicity, oxidative stress and accumulation of collagen were detected in the liver. The expression levels of inducible NOS (iNOS) and nuclear factor kappa-B (NF-κB) activity in the liver after CCl₄ treatment were increased but eNOS expression and activator protein-1 (AP-1) activity were decreased. Both SMT and l -arginine effectively reduced CCl₄ induced oxidative stress and collagen formation, but l -arginine showed a significantly greater suppression of collagen formation, iNOS expression and NF-κB activity. l -Arginine also restored the level of eNOS and AP-1 activity. l -Arginine was more effective than SMT in suppressing liver fibrosis. l -Arginine might improve NO production which facilitates hepatic blood flow and thus retards liver fibrogenesis. Our results showed that the reduced eNOS expression in CCl₄-treated mice was reversed by l -arginine. Furthermore, l -arginine also reversed the reduced AP-1 activity, an eNOS promoter.