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1.
Summary Calcitonin gene-related peptide-immunoreactive cells were identified within the epithelium of distal conducting airways in the human fetus and infant. Several peptides and amines, including calcitonin, have been identified previously within a specific population of airway epithelial cells. These cells, referred to as pulmonary neuroendocrine cells, are postulated to be airway chemoreceptors responsible for changes in ventilation and perfusion in response to changes in airway gas composition. Calcitonin gene-related peptide immunoreactive cells could be identified throughout the period of development studies (20 weeks gestation to 3 months of age), but were present in only limited numbers in less than 50% of individuals (n=23). In contrast, large numbers of calcitonin gene-related peptide immunoreactive cells were identified in 100% of infants (1–3 months, n=5) with bronchopulmonary dysplasia. The differential processing of mRNA transcribed from the calcitonin gene in neural and non-neural tissue suggests that calcitonin, rather than calcitonin gene-related peptide, is the primary product of translation in pulmonary neuroendocrine cells. However, considering the potent vasodilatory and bronchoconstrictive effects of calcitonin gene-related peptide, its presence in pulmonary neuroendocrine cells, even in small amounts, may be important in controlling pulmonary vaso- and/or bronchomotor tone. The presence of large numbers of calcitonin gene-related peptide immunoreactive cells in infants with bronchopulmonary dysplasia suggests that calcitonin gene-related peptide may be one further agent contributing to the pulmonary pathophysiology seen in this disease. 相似文献
2.
Eveline E. Schneeberger M.D. 《Cell and tissue research》1988,251(2):417-423
Summary The endothelial glycocalyx, a polyanionic structure which may regulate the passage of solutes and water through the endothelium, readily binds cationic ferritin (CF). In normal, nonexchange-transfused rats, however, only 7.5% and 6.0% of the luminal plasma membrane and 7.5% and 5.0% of vesicle diaphragms on the thick and thin side of pulmonary capillaries, respectively, bound cationic ferritin. With the graded removal of circulating proteins by exchange transfusion with fluorocarbon emulsion, up to 89 and 82% of the luminal surface, and 76 and 73% of vesicle diaphragms on the thick and thin sides, respectively, bound CF. Although the extent of binding on the thin side was consistently less than on the thick side, the difference was not statistically significant. The extensive binding of CF to the glycocalyx in totally exchange-transfused rats was completely reversible upon addition of lyophilized rat serum protein to the perfusate. These data suggest that in vivo anionic sites of the endothelial glycocalyx are partially masked by adsorbed plasma proteins. 相似文献
3.
The distribution of the pulmonary artery and vein of the orangutan lung was examined. The right pulmonary artery runs obliquely
across the ventral side of the right bronchus at the caudally to the right upper lobe bronchiole. It then runs across the
dorsal side of the right middle lobe bronchiole. Thereafter it runs obliquely across the dorsal side of the right bronchus,
and then along the dorso-medial side of the right bronchus. This course is different from that in other mammals. During its
course, it gives off branches which run mainly along the dorsal or lateral side of each bronchiole. The left pulmonary artery
runs across the dorsal side of the left middle lobe bronchiole, then along the dorso-lateral side of the left bronchus, giving
off branches which run along each bronchiole. The pulmonary veins run mainly the ventral or medial side of, along or between
the bronchioles. In the left lung, the left middle lobe vein has two trunks; one enters the left atrium, and the other enters
the left lower lobe pulmonary venous trunk. This is also different from that found in most mammals. Finally, the pulmonary
veins enter the left atrium with four large veins. 相似文献
4.
The lungs of three silvered lutongs (Presbytis cristata) were examined. The right and left lungs have the dorsal, lateral, ventral, and medial bronchiole systems, which arise from
the corresponding sides of both bronchi, respectively. Bronchioles in the dorsal and lateral bronchiole systems are well developed,
whereas those in the ventral and medial bronchiole systems are poorly developed and lack some portions. According to the fundamental
structure of bronchial ramifications of the mammalian lung (Nakakuki, 1975, 1980), the right lung consists of the upper, middle, lower, and accessory lobes, whereas the left lung consists of
a bilobed middle lobe and a lower lobe, in which the right upper lobe is extremely well developed. The right pulmonary artery
runs across the ventral side of the right upper lobe bronchiole, and then across the dorsal side of the right middle lobe
bronchiole. Initially it runs along the lateral side of the right bronchus and then gradually comes to run along the dorsal
side. During its course, it gives off branches which run mainly along the dorsal or lateral side of the bronchiole. The left
pulmonary artery runs across the dorsal side of the left middle lobe bronchiole, and then follows the same course as that
in the right lower lobe. The pulmonary veins run medially or ventrally to the bronchioles, and finally enter the left atrium
as four or five large veins. 相似文献
5.
In the present study, anti-metastatic effect of Z-100 on the spontaneous pulmonary metastases of Lewis lung carcinoma (3LL)
was examined in an attempt to regulate suppressor T cells. When Z-100 (10 mg/kg) was daily injected i.p. after 3LL inoculation,
survival rate of these mice was increased significantly (p<0.05). In addition, the number of pulmonary metastatic colonies of 3LL in Z-100-treated mice were significantly decreased
by 38% at 21 days, as compared with that of control mice (p<0.05). Along with the decrease of pulmonary metastases, suppressor cell activity was also gradually reduced in these mice,
as compared with that of control mice. When splenic suppressor cells (5×107 cells) from 3LL-bearing mice were adoptively transferred into normal mice (recipients) just before inoculation of 3LL, the
development of pulmonary metastases in recipients was significantly accelerated. However, splenocytes from 3LL-bearing mice
treated with Z-100 did not affect the development of pulmonary metastasis. The potential to accelerate the metastasis of splenic
mononuclear cells from 3LL-bearing mice was decreased significantly by the treatment with anti-Thy 1.2 monoclonal antibody
(mAb), anti-Lyt 2.2 mAb or anti-CD11b mAb followed by complement. IL-4 activity in the sera of 3LL-bearing mice was detected
15 days after tumor inoculation (13 pg/ml) and gradually increased (18 pg/ml) 20 days after tumor inoculation. However, when
Z-100 (10 mg/kg) was daily injected i.p., IL-4 activity in sera was decreased significantly, and the IL-4 activity was not
detected in these mice on day 20. These results suggest that Z-100 could inhibit the pulmonary metastases in 3LL-bearing mice
through the inhibition of suppressor T cell activity and a possible candidate of its effector molecule, IL-4. 相似文献
6.
Ian G. Town Gary J. Phillips Edile Murdoch Stephen T. Holgate Frank J. Kelly 《Free radical research》1993,18(4):211-221
The time course and nature of the pulmonary inflammatory and antioxidant responses, both during and after hyperoxic-induced acute lung injury were studied in the preterm guinea pig. Three-day preterm (65 days gestation) guinea pigs were randomly exposed to either 21% O2 (control) or 95% O2 (hyperoxia) for 72 hours. All pups were then maintained in ambient conditions for up to a further 11 days, during which time lung damage was monitored. In animals exposed to hyperoxia, evidence of acute lung injury and inflammation was characterized by a marked increase in microvascular permeability and elevated numbers of neutrophils in bronchoalveolar lavage fluid. Protein concentration, elastase-like activity and elastase-inhibitory capacity in lavage fluid were at a maximum at the end of the 72 hours hyperoxic exposure. Four days later, all values had returned to control levels. In contrast, increased numbers of neutrophils, macrophages and lymphocytes were recovered in the lavage fluid during this early recovery period. Coinciding with the influx of inflammatory cells, there was a significant increase in glutathione peroxidase, manganese superoxide dismutase and catalase activities in immature lung. Lung copper/zinc superoxide dismutase activity remained unchanged during both experimental periods. The strong temporal relationship between the influx of inflammatory cells to the lung and the induction of pulmonary antioxidant enzyme defences suggests that a common mechanism underlies both responses. These findings have led us to regard inflammation in the hyperoxic-injured immature lung as a beneficial event and not, as previously suggested, as part of the injurious process. 相似文献
7.
Estrus in a 10-yr-old brown hyena was described by monitoring urinary steroid metabolites. These studies were repeated the succeeding year and combined with ultrasonography, vaginal cytology, and laparoscopy to further aid in identifying natural and induced estrus. Collection of semen from a 14-yr-old male brown hyena was accomplished by electroejaculation. Use of frozen semen once during natural estrus and again during estrus induced with follicle stimulating hormone (FSH) did not result in pregnancy. Further studies with this animal indicate that stimulation with gonadotropin releasing hormone (GNRH), rather than FSH, may be the more appropriate treatment for stimulating ovulation in canids or related species. While this study did not result in conception, a significant step toward that end was realized by utilizing urinary estrogen to monitor the estrus cycle. 相似文献
8.
The effects of ouabain, a known inhibitor of lymphoproliferation, were studied in relation to the cytotoxic effector function of human peripheral blood mononuclear leukocytes (MNL) against chicken red blood cell (CRC) targets. MNL effectors lysed 51Cr-labeled CRC targets in the presence of PHA (mitogen-induced cellular cytotoxicity—MICC) or rabbit anti-CRC antibody (antibody-dependent cellular cytotoxicity—ADCC) in the absence of ouabain. The addition of ouabain to the cytotoxic reaction caused profound diminution of MICC with greater than 90% suppression of killing at ouabain concentrations of 5 × 10?4M; ADCC was much more resistant to the effects of ouabain with only 60 to 70% inhibition of killing at similar ouabain concentrations (P < 0.01). Similar ouabain inhibition of MICC occurred whether the effector cell populations were unseparated MNL, depleted of monocytes, enriched for T cells, or depleted of T cells, suggesting a generalized activity by ouabain against all effector cells active in MICC. Ouabain inhibition of MICC could be overcome by increasing PHA concentrations, indicating that ouabain inhibition was not due to irreversible toxic effects on effector cells. Increasing the concentration of anti-CRC antibody resulted in increased killing in this ADCC system and, paradoxically, ADCC cultures with the highest antibody concentrations were more completely inhibited by ouabain. This enhanced inhibitory effect of ouabain on ADCC cultures with the highest antibody concentrations was not observed when the effector cell population was first depleted of phagocytic cells, suggesting a preferential inhibitory action by ouabain against monocyte effectors in ADCC. Thus, the differential inhibitory effects of ouabain on MICC and ADCC against CRC targets may be in part explained by the differing ouabain sensitivities of the various effector cell subpopulations involved in these cell-mediated cytotoxic events. 相似文献
9.
We have previously shown that ouabain inhibits mitogen-induced cellular cytotoxicity (MICC) and antibody-dependent cellular cytotoxicity (ADCC) against chicken red cell (CRC) targets. We now report that ouabain increases spontaneous killing of CRC targets in the absence of mitogen or antibody. Spontaneous cytotoxicity by fresh mononuclear leukocytes (MNL) was enhanced by ouabain in a dose-dependent fashion and was maximal at a ouabain concentration of 5 × 10?5M. Removal of phagocytic cells from the MNL effector cell population abrogated ouabain-induced spontaneous cytotoxicity, suggesting that the effector cell activated by ouabain was a monocyte. Ouabain-induced spontaneous cytotoxicity was relatively inefficient compared to MICC or ADCC and was only demonstrated consistently at effector:target cell ratios higher than those routinely employed for MICC and ADCC. Very low concentrations of ouabain (5 × 10?9M) also enhanced spontaneous cytotoxicity of MNL precultured for 7 days, when added at either Day 0 or Day 6 of preculture. The cell effecting spontaneous cytotoxicity after 7 days of culture has been previously shown to be a monocyte. Thus, ouabain has opposing effects on cell-mediated cytotoxic functions: it inhibits MICC and ADCC against CRC targets, but stimulates spontaneous, monocyte-mediated cytotoxicity against the same targets. 相似文献
10.
目的:探讨应用改良后的呼吸机对病室环境卫生学的影响。方法:对10例产碳青霉烯酶肺炎克雷伯菌肺感染应用呼吸机的患者和40例肺部感染耐甲氧西林金黄色葡萄球菌(MRSA)使用呼吸机的患者进行分组试验,对病室环境卫生学监测结果进行统计分析。机器改良方法是呼吸机的呼气阀处连接一条螺纹管,将带菌空气引出,消毒后排放。结果:肺部感染产碳青霉烯酶肺炎克雷伯菌应用改良后呼吸机的一组在空气、床头桌、水池、操作中人员手的阳性率分别为20%、10%、20%、10%,较未改良的对照组为80%、70%、70%、50%有明显的下降。肺部感染MRSA使用有创改良呼吸机组空气、床头桌、水池、操作中人员手的阳性率分别为10%、10%、5%、10%均低于无创改良组的20%、20%、10%、20%。结论:此种方法有效地降低了环境的污染程度,降低了医源性医院感染的风险。加强洗手和隔离等卫生预防学措施可以有效的降低MRSA的医院感染率。 相似文献