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Foreign body aspiration requires emergency bronchoscopic examination when the product is chemically active. We describe the case of a female patient who aspirated a ferrous sulfate tablet that, in spite of being extracted immediately, caused lesions that persisted in the bronchial tree for 6 weeks. We then discuss the potential of ferrous sulfate substance to cause damage to the tracheobronchial tree.  相似文献   
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Microtubule-targeting agents (MTAs) are effective drugs for cancer treatment. A novel diaryl [1,2]oxazole class of compounds binding the colchicine site was synthesized as cis-restricted-combretastatin-A-4-analogue and then chemically modified to have improved solubility and a wider therapeutic index as compared to vinca alkaloids and taxanes. On these bases, a new class of tricyclic compounds, containing the [1,2]oxazole ring and an isoindole moiety, has been synthetized, among which SIX2G emerged as improved MTA. Several findings highlighted the ability of some chemotherapeutics to induce immunogenic cell death (ICD), which is defined by the cell surface translocation of Calreticulin (CALR) via dissociation of the PP1/GADD34 complex. In this regard, we computationally predicted the ability of SIX2G to induce CALR exposure by interacting with the PP1 RVxF domain. We then assessed both the potential cytotoxic and immunogenic activity of SIX2G on in vitro models of multiple myeloma (MM), which is an incurable hematological malignancy characterized by an immunosuppressive milieu. We found that the treatment with SIX2G inhibited cell viability by inducing G2/M phase cell cycle arrest and apoptosis. Moreover, we observed the increase of hallmarks of ICD such as CALR exposure, ATP release and phospho-eIF2α protein level. Through co-culture experiments with immune cells, we demonstrated the increase of (i) CD86 maturation marker on dendritic cells, (ii) CD69 activation marker on cytotoxic T cells, and (iii) phagocytosis of tumor cells following treatment with SIX2G, confirming the onset of an immunogenic cascade. In conclusion, our findings provide a framework for further development of SIX2G as a new potential anti-MM agent.  相似文献   
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The matrix metalloproteinases appear to play a key role in mammary tissue remodeling during involution. By immunoprecipitation and immunoblot using antibodies against 60K gelatinase which appears during involution a 90K polypeptide has been identified as its inactive proenzyme in the early involuting rat mammary gland. 90K polypeptide was isolated from the second day involuting rat mammary gland by immunoaffinity chromatography. On proteolytic digestion, the inactive 90K polypeptide was converted to active gelatinase. Primary cultures of mammary epithelial cells secreted the 90K polypeptide. These results indicated that the 60K inducible MMP involved in mammary gland involution and remodeling is produced as a 90K proenzyme which is activated by proteolysis in the extracellular sites.  相似文献   
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OBJECTIVES: To find the social, demographic and family characteristics, the psychological malaise and reasons for consultation of normal and hyper-attenders at a primary care practice. DESIGN: Crossover study with a control. SETTING: Primary care. PATIENTS: 127 hyper-attenders (they attended the practice as often as, or more often than, the mean number of visits, stratified by sex and age) and 120 normal attenders chosen by stratified random sampling. INTERVENTIONS: Questionnaire with characterisation data, family demography, psychological malaise (Goldberg general health questionnaire) and reasons for consultation. RESULTS: To be considered a hyper-attender, the number of attendances per year ranged from > or = 8 (in 15 to 44-year olds) to > or = 20 (in men over 65). Hyper-attenders were about 12% of almost all groups, except in men between 45 and 64 and women over 64, in whom it was around 18%. We found no relevant differences between normal and hyper-attenders as to demography or perception of family function. In almost 60% of hyper-attenders and 34% of normal attenders (p < 0.001), psychological malaise was detected. CONCLUSIONS: If the definition of hyper-attenders is stratified by age and sex, their social and demographic characteristics are very different from in other studies, even though there are a similar number of them. However, these demographic and/or family characteristics are similar in normal and hyper-attenders.  相似文献   
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Manual performance, direction, and degree of laterality were tested in monozygotic (MZ) twins (8-12 years old) of known chorion type and dizygotic (DZ) twins. Three manual tasks rarely employed in twin studies were used; dot-filling, tapping, and peg-moving tasks. No chorion effect was observed: the monochorionic and dichorionic MZs differed neither for frequency of discordant pairs nor for handedness, laterality measurements, and manual performance. The pooled MZs and DZs were then compared in a classic twin design. The within-pair resemblance was not higher in MZs than in DZs for variables measuring level of manual performance. For laterality scores intraclass correlations were close to zero in MZ and DZ twin groups.  相似文献   
108.
The permanent fibrocyte-like fish cell line RTG-2 from rainbow trout (Oncorhynchus mykiss) gonads was investigated by means of light and scanning electron microscopy with respect to alterations as a consequence of sublethal exposure to 0, 1, 10, 16, 25, and 50 mg/liter 3,5-dichlorophenol (3,5-DCP) for 24 h. Control RTG-2 cells were spindle-like in shape and almost three times longer than wide. In subconfluent cultures, they displayed widely spread, flat leading lamellae and formed small groups. Along the edges of the cell protrusions, numerous retraction fibrils could be identified. Except for shallow ridges and small folds, the surface of untreated cells was completely smooth. Following exposure to 3,5-DCP, distinct dose-dependent alterations in cell shape, the appearance of surface blebs and invaginations, as well as progressive retraction of cell extensions could be observed from the lowest test concentration. Morphological changes could be correlated to suppression of lactate dehydrogenase and reduced neutral red retention capacity.  相似文献   
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