Objective To understand the latest research developments of the formation mechanism of psammoma body in human tumors and related issues. Methods Related domestic and foreign literatures were widely referred, analyzed, and reviewed. Results Psammoma body is unique pathological calcification in some tumors, which is arranged in concentric, laminar circles microscopically. Psammoma body is commonly seen in thyroid papillary carcinoma, meningiomas, ovarian serous papillary carcinoma, and so on. Conclusions Although arranged in concentric, laminar circles microscopically in tumor, the formation process of psammoma body is not entirely the same in different tumors. A comprehensive and objective understanding of psammoma body would be useful in cancer diagnosis and treatment.
In order to overcome the shortcomings of high false positive rate and poor generalization in the detection of microcalcification clusters regions, this paper proposes a method combining discriminative deep belief networks (DDBNs) to automatically and quickly locate the regions of microcalcification clusters in mammograms. Firstly, the breast region was extracted and enhanced, and the enhanced breast region was segmented to overlapped sub-blocks. Then the sub-block was subjected to wavelet filtering. After that, DDBNs model for breast sub-block feature extraction and classification was constructed, and the pre-trained DDBNs was converted to deep neural networks (DNN) using a softmax classifier, and the network is fine-tuned by back propagation. Finally, the undetected mammogram was inputted to complete the location of suspicious lesions. By experimentally verifying 105 mammograms with microcalcifications from the Digital Database for Screening Mammography (DDSM), the method obtained a true positive rate of 99.45% and a false positive rate of 1.89%, and it only took about 16 s to detect a 2 888 × 4 680 image. The experimental results showed that the algorithm of this paper effectively reduced the false positive rate while ensuring a high positive rate. The detection of calcification clusters was highly consistent with expert marks, which provides a new research idea for the automatic detection of microcalcification clusters area in mammograms.
Soft tissue opacities are often found by chance during radiographic examinations, especially in panoramic radiography. Because of the diversity of locations and causes, it is easily overlooked by dentists and even radiologists. Even if abnormal calcification is detected, it is difficult to identify its category and clinical relevance. For some soft tissue opacities associated with high-risk diseases, misdiagnosis is likely to delay treatment. Through reviewing the literature and screening the panoramic images from the disease database of West China Hospital of Stomatology, Sichuan University, this review summarizes and classifies the soft tissue opacities appearing in panoramic images, and discusses the clinical correlation to provide the reference for diagnosis, treatment, and prevention of related diseases.
Abstract: Objective To summarize the 17-year clinical experience of coronary artery bypass grafting (CABG). Methods From April 1987 to May 2004, total 253 patients with coronary artery disease underwent CABG. The operation were performed in 217 patients under cardiopulmonary bypass (CPB) with moderate hypothermia, because of calcified ascending aorta, partial replacement of ascending aorta wall with apiece of Gore-Tex graft for the proximal anastomosis were done in 10 patients. Off-pump coronary artery bypass grafting (OPCAB) were performed in 30 patients. The operation under CPB with heart beating were performed in 6 patients. Cardiac valvular operations were performed in 15patients. Left atrium myxoma operation was performed in 1 patient. Left ventricular aneurysm plasty operation were performed in 10 patients. Results Total mortality rate was 7.9% (20/253). There was significant difference between the mortality rate of the first 10 years (16.0%,8/50) and that of the last 7 years (5.9%,12/203; χ2=5.62,Plt;0.05). The causes of death were: 3 patients died on table because of low cardiac output after valvular replacement though emergent CABG were conducted, 2 patients died of multiple organ failure after valvular replacement and emergent CABG had undergone, 3 patients died of ventricular fibrillation during closing the sternum, 6 patients died of multiple organ failure caused of severe lung infection, 2 patients died of ventricular fibrillation after operation, and 4 patients died of acute renal failure. One hundred and fiftyseven patients (67.4%, 157/233) were followed up, follow-up time was 6 months to 15 years. Three of them died of unknown causes, most of them have improved life quality. There were 87 patients in New York Heart Association (NYHA) class Ⅰ, 49 patients in NYHA class Ⅱ, 16 patients in NYHA classⅢ, and 2 patients in NYHA classⅣ. Conclusion When the experience of surgery and postoperative care is matured, CABG is a safe method for treatment of coronary artery disease. Partial replacement of ascending aorta wall with GoreTex graft for proximal anastomosis of the graft is acandidate method for the treatment of patients with calcified ascending aorta.
Objective To investigate the management during offpump coronary artery bypass grafting (OPCAB) for patients with ascending aorta atherosclerosis and to find appropriate treatment for minimizing the postoperative cerebrovascular accidents. Methods 236 patients with ascending aorta atherosclerosis were retrospectively analyzed underwent OPCAB in this hospital from Sep.2004 to Dec.2007, 4 of them received “No-touch” technique, 35 of them had the proximal anastomoses with the Enclose assistant, and 197 of them had the proximal anastomoses with the assistant of Heartstring. Hemodynamic indexes were consecutively monitored, blood streams of grafts was monitored by transit time flow measurement (TTFM) to evaluate the quality. Results Distal anastomoses 881,proximal anastomoses 267, the blood stream of 881 grafts was monitored, the mean flow was 16.2±18.7 ml/min, and the pulsatility index (PI) were 4.9±2.3, indicating the good quality of all grafts. The change of hemodynamic indexes including mean artery pressure (MAP, 78.1±10.4 mmHg vs. 80.9±8.1 mmHg), pulmonary capillary wedge pressure (PCWP, 11.9±3.6 vs. 10.9±2.1 mmHg), mean pulmonary artery pressure (MPAP, 17.3±4.3 mmHg vs. 15.3±2.8 mmHg), cardiac output (CO, 4.2±1.2 L/min vs. 4.5±1.6 L/min), center vinous pressure (CVP, 9.2±2.3cmH2O vs. 9.3±1.8 cmH2O), heart rate (HR, 71.4±14.0 beats/min vs. 73.4±16.5 beats/min), there were no statistically difference between before and after proximal anastomoses (Pgt;0.05). Two patients died of low cardio output during operation, 4 patients with transient ischemic attack were improved by 2 months medical therapy, and others had no postoperative complications as perioperative myocardial infarction etc, and the time of stay hospital was 10.5±4.2d. Followup 3-24 months for 185 patients, all living patients had no myocardial or cerebrovascular accidents, the symptoms were alleviated and myocardiac function improved. Conclusion Assessing the degree of the ascending aorta atherosclerosis sufficiently before and during the operation, choosing different operational strategy, and decreasing the manipulation of aorta can decrease the incidence of cerebrovascular accident and get better clinical result.
This paper reported a 75-year-old female patient. She was admitted to our hospital for “repeated chest pain, shortness of breath for more than 5 years, and syncope 3 times”. The CT scan of the patient showed severe aortic valve stenosis, bicuspid valve, and severe calcification; then she underwent transcatheter aortic valve replacement in our hospital. After the prosthesis was implanted, there was a significant paravalvular leak. Considering the triangular area formed between the calcified clumps, the valve was not fully dilated. Paravalvular leak closure was performed during the operation, attempted through the valve stent mesh to closuring. A rare incarceration of the transmitter occurred. An attempt was made to pull out the incarcerated transmitter through a pull-up technique, which resulted in the prosthesis prolapse. The patient was eventually transferred to surgery aortic valve replacement.
ObjectiveExtracting the endothelial cells or all endothelial cells and interstitial cells from the cryopreserved homograft valves (HV), to evaluate the immunogenicity of this two kinds of decellular HV. MethodsFor extracting the endothelial cells, the leaflet and wall of the HV were decellularized by a 4-step detergent-enzymatic extraction method involving the 1% triton in combination with RNase (1μg/ml) and DNase (10μg/ml). For extracting the endothelial cells and interstitial cells, the leaflet and wall of the HV were decellularized by a 3-step detergent-enzymatic extraction method involving the 1% deoxycholic acid (DOA) in combination with RNase (20μg/ml) and DNase (200μg/ml). HLA-DR antigen expression was detected by using immunohistochemical techniques. The valve and wall of the HV were transplanted subcutaneously in the mice for 8 weeks, and the histology, calcium assay and calcium content were examined. ResultsFor the staining of the HLA-DR antigens, the immunogenic potential of the HV with extracting all endothelial cells and interstitial cells or only the endothelial cells was lower than cryopreserved HV, but it more obviously decreased for the HV with extracting all endothelial cells and interstitial cells. After 8 weeks embedded in the mice, the histological signs of the inflammatory reactions and the calcification extent to the cryopreserved HV and the HV with only extracting endothelial cells were stronger than the HV with extracting all endothelial cells and interstitial cells predominantly. And calcification extent or the inflammatory reactions to the wall of the HV were more severe than those of the leaflet. ConclusionsThe immunogenicity of the HV with extracting all endothelial cells and interstitial cells is much less than HV with only extracting endothelial cells. The histological signs of the inflammatory reactions and the calcification extent in vivo experiments is obviously decreased. For the HV with only extracting endothelial cells, though the histological signs of the inflammatory reactions slightly decrease, the calcification extent in vivo experiments is more severe, especially for the wall. The interstitial cells may be the important factor for the donor-reactive immune responses that is related to the graft calcification or destruction after implantation.