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101.
To determine if macrophages regulate the numbers of fibroblasts in the silicotic lung, we exposed macrophages to quartz particles in vitro and in vivo and determined if the secretory products from these cells influenced the proliferation of cultured lung fibroblasts. Macrophages were recovered by lavage from the lungs of normal guinea pigs. Monolayers of these cells were exposed to sized quartz particles for 2 h. Macrophages were exposed to silica in vivo by the intratracheal injection of quartz particles. Macrophages were recovered from the silicotic guinea pigs 2, 14, 42, and 180 days after injection. Monolayers of these cells were also cultured for 2 h in the absence of a stimulus. Fibroblasts were derived from explants of the lungs of young guinea pigs. The effect of supernatants from the macrophage cultures on the proliferation of fibroblasts in vitro was determined in all experiments by measuring the incorporation of tritiated thymidine, and in some cases by direct cell counts. Macrophages exposed to quartz in vitro or for a short time (2 days) in vivo inhibited the proliferation of lung fibroblasts. In contrast, macrophages exposed in vivo for 42 and 180 days enhanced the proliferation of fibroblasts. These results suggest that alveolar macrophages from guinea pigs elaborate factors with opposing effects on the growth of fibroblasts and that the duration of exposure to silica is an important determinant of the predominant effect. These results also lend support to the notion that alveolar macrophages regulate the number of fibroblasts in the normal and the diseased lung.  相似文献   
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Three types of serous products were detected in the syncytial cutaneous glands of the leptodactylid tungara frog, Engystomops pustulosus: type Ia, granules with wide halos and variable density cores; type Ib, high density granules without halos; and type II, vesicles containing a finely dispersed product. Ultrastructural evidence revealed that these products were manufactured by different serous gland types and excluded that they represented different steps in the secretory cycle of a single gland type. Indeed, secretory maturation affecting the products released by the Golgi apparatus proceeded through different mechanisms: confluence (vesicles), interactions between syncytium and secretory product (type Ib granules), and a combination of both processes (type Ia granules). In conclusion, this investigation of secretory maturation was shown to be a suitable approach for the identification of serous gland polymorphism and demonstrated that the tungara frog belongs to the minority of anuran species characterized by this peculiar morpho‐functional trait. Anat Rec, 298:1659–1667, 2015. © 2015 Wiley Periodicals, Inc.  相似文献   
105.

Purpose

We examined different approaches aimed to deal with the signal fluctuation of pancreatic T2* values due to fat infiltration in order to obtain accurate estimates of iron overload.

Methods

Pancreatic T2* values were assessed in 20 patients (13 females, 37.24 ± 9.12 years) enrolled in the Myocardial Iron Overload in Thalassemia network without and with the application of fat suppression-FS (T2*-NoFS and T2*-FS). T2* values were assessed in three different ways: (1) from the immediate fit (original T2*); (2) discarding the echoes until the achievement of a good visual concordance between the signal and the model (final_vis T2*); (3) eliminating the echoes until the achievement of a fitting error (known) <5% (final_thres T2*).

Results

For the T2*-NoFS sequence the original T2* values were significantly higher than the final_vis T2* values (difference:4.8 ± 6.1 ms; P < 0.0001) and the final_thres T2* values (difference:4.3 ± 6.1 ms; P = 0.006). For the T2*-FS sequence the original T2* values were comparable to final_vis and final_thres T2* values. The original T2*-FS values were significantly different from the original T2*-NoFS values. The final_vis T2*-FS values were comparable to the final_vis T2*-NoFS values and the final_thresh T2*-FS values were comparable to the final_thresh T2*-NoFS values. For both T2*-FS and T2*-NoFS sequences, the final_thres T2* values were not significantly different from the final_vis T2* values and no bias was present.

Conclusions

In the clinical practice, an accurate pancreatic iron overload assessment should be done by applying FS and, when needed, by discarding the TEs until the fitting error goes below 5%.
  相似文献   
106.

Introduction

Fractures of the orbital-maxillo-zygomatic complex are among the most common fractures affecting the facial skeleton. Goal of surgical treatment is the realignment of fracture lines for a complete functional and aesthetic rehabilitation.

Materials and Methods

From January 2008 to January 2011 in the Department of Maxillofacial Surgery of Complesso Integrato Columbus of the Università Cattolica del Sacro Cuore in Rome, 25 patients, affected by comminute fractures of the anterior wall of the maxillary sinus associated with fractures of the orbital-maxillary complex were selected. The synthesis of the larger fracture fragments was performed by plates and screws (1.5 mm) while a biocompatible glue (N-Butyl-2-Cyanoacrylate–Glubran2®) was applied to treat the comminute fractures of the anterior wall of the maxillary sinus.

Results and Conclusion

The aim of our article is to report our experience and a review of the literature on application of–Butyl-2-Cyanoacrylate for treatment of comminute fractures of the anterior wall of the maxillary sinus. According to the results achieved in our study the N-Butyl-2-Cyanoacrylate can be indicated to treat comminuted fractures of the anterior wall of the maxillary sinus which could not easily be treated with internal rigid fixation.  相似文献   
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Morgana/CHP‐1 is a ubiquitously expressed protein able to inhibit ROCK II kinase activity. We have previously demonstrated that morgana haploinsufficiency leads to multiple centrosomes, genomic instability, and higher susceptibility to tumour development. While a large fraction of human cancers has shown morgana down‐regulation, a small subset of tumours was shown to express high morgana levels. Here we demonstrate that high morgana expression in different breast cancer subtypes correlates with high tumour grade, mitosis number, and lymph node positivity. Moreover, morgana overexpression induces transformation in NIH‐3T3 cells and strongly protects them from various apoptotic stimuli. From a mechanistic point of view, we demonstrate that morgana causes PTEN destabilization, by inhibiting ROCK activity, hence triggering the PI3K/AKT survival pathway. In turn, morgana down‐regulation in breast cancer cells that express high morgana levels increases PTEN expression and leads to sensitization of cells to chemotherapy. Copyright © 2014 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd  相似文献   
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