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Objective To summarize the clinical features of adrenocorticotropic hormone (ACTH)⁃dependent Cushing's syndrome (CS) with multiple endocrine neoplasia (MEN). Methods Based on the pituitary tumor database of Peking Union Medical College Hospital of China Pituitary Disease Register Network (CPDRN), 18 patients with ACTH ⁃ dependent CS complicated with MEN from January 1984 to September 2020 were collected. The clinical manifestations, involved other endocrine glands, laboratorial and imageological examinations were analyzed. Results Among 18 patients, 13 cases were Cushing's disease and 5 cases were ectopic ACTH syndrome (EAS); 15 cases were MEN1 type, 2 cases were MEN2 type and one case was MEN4 type. The clinical manifestations were subclinical CS in 6 cases and overt CS in 12 cases. All cases had osteopenia or osteoporosis. Urolithiasis accounted for 11/18 cases. Regarding the involved endocrine glands, pituitary ACTH adenoma accounted for 13/18 cases, prolactinoma accounted for 4/18 cases, hyperparathyroidism accounted for 15/18 cases, pancreatic neuroendocrine tumors accounted for 13/18 cases and adrenal adenomas and hyperplasia accounted for 10/18 cases. Laboratorial examinations showed the average morning serum cortisol was (652.90 ± 254.90) nmol/L, the morning ACTH was (13.38 ± 8.73) pmol/L and the 24 h urinary free cortisol was 446.35 (233.08, 531.10) µg. Serum prolactin was elevated in 2 cases, parathyroid hormone was elevated in 13 cases and serum calcium was elevated in 11 cases. In imageological examinations, there were pituitary microadenoma in 12 cases, pituitary macroadenoma in 3 cases, adrenal adenoma in 8 cases, thickened adrenal in 4 cases, adrenal pheochromocytoma in 2 cases, and paraganglioma in one case. Genetic test showed 3 cases had MEN1 gene mutation including c.1183C ＞ T, c.1579C ＞ T and c.1174G ＞ T. Conclusions ACTH⁃dependent CS with MEN is a rare disease with complex manifestations. The most common symptom is osteopenia/osteoporosis. The most common cause of CS is pituitary microadenoma. MEN1 is the most common MEN type, and primary hyperparathyroidism is the most common type of affected endocrine glands, followed by pancreatic neuroendocrine tumors. doi：10.3969/j.issn.1672⁃6731.2021.03.008

Digital tomosynthesis (DTS) technology has attracted much attention in the field of nondestructive testing of printed circuit boards (PCB) due to its high resolution and suitability to thin slab objects. However, the traditional DTS iterative algorithm is computationally demanding, and its real-time processing of high-resolution and large volume reconstruction is infeasible. To address this issue, we in this study propose a multiple multi-resolution algorithm, including two multi-resolution strategies: volume domain multi-resolution and projection domain multi-resolution. The first multi-resolution scheme employs a LeNet-based classification network to divide the roughly reconstructed low-resolution volume into two sub-volumes namely, (1) the region of interest (ROI) with welding layers that necessitates high-resolution reconstruction, and (2) the remaining volume with unimportant information which can be reconstructed in low-resolution. When X-rays in adjacent projection angles pass through many identical voxels, information redundancy is prevalent between the adjacent image projections. Therefore, the second multi-resolution scheme divides the projections into non-overlapping subsets, using only one subset for each iteration. The proposed algorithm is evaluated using both the simulated and real image data. The results demonstrate that the proposed algorithm is approximately 6.5 times faster than the full-resolution DTS iterative reconstruction algorithm without compromising image reconstruction quality. [ABSTRACT FROM AUTHOR]

An affine transformation for determining the edge parameters of digital, anisotropic images is introduced. The transformation adapts the moment-based operator to enhance its edge-detection accuracy during the approximation of rectangular image pixels as square pixels. It is carried out prior to integration over the circular region within the rectangular window for edge detection. To test its validity, artificial images were used to generate image data at a pixel aspect ratio of 4/3.

BT network has been widely used in the Internet. The nodes in BT network feature anonymity and freedom, which is more conducive to hide the identity and to create steganographic system. We used Lehmer code algorithm to construct a hidden communication system in BT network based on plug-in technology. The function of this system is that a special subgroup of peers in a BT network can identify each other and communicate without suspicion among regular peers. In this process, the hidden information is transmitted and the BT network also works normally. The system makes steganographic channels secretly without exposing anyone's identity. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the disinfection efficacy of MTAD on Enterococcus faecalis biofilm and smear layer colonization in apical isthums of the root canal system., Methods: Fifteen extracted human maxillary first premolars with isthmus anatomic structure which confirmed by stereo-microscope were contaminated with E. faecalis in vitro and randomly divided into 5 groups: the first group was not treated serving as a baseline control, the second group was treated by normal saline (NS) serving as negative control, the third group was treated by MTAD , the forth group by 5.25% NaOCl, and the fifth group by 5.25% NaOCl + EDTA. All roots in the latter four groups were instrumented by Protaper rotary files and irrigated with respective irrigant, then the roots were split longitudinally and a scanning electron microscope was used to evaluate the antibacterial activity and smear layer cleaning ability of irrigants on isthmus., Results: In the first group, E. faecalis colonized on the isthmus surface and aggregated together to form biofilm-like microorganism community, some bacteria also colonized in the dentinal tubules. When treated with NS, both smear layer and bacteria remained (median of smear layer score was 5). MTAD can remove partial smear layer, and have limited antibacterial activity, some bacteria embedded in smear layer (the median was 3) and were destroyed; In 5.25% NaOCl treatmentgroup, the smear layer was not removed (median of smear layer score was also 5), but all bacteria on the surface were extinguished. The combined use of 5.25% NaOCl and EDTA produced a cleaner isthmus surface and had marked antimicrobial effect, with the median of smear layer score being only 1., Conclusion: MTAD may permeate into the isthmus area of apical root canal system, but only performed a partial effect of disinfection and limited antibacterial activity. Sodium hypochlorite cooperated with EDTA can remove infection effectively in the isthmus area.

In this paper, a low-cost PC-based, high-quality and interactive 3D stereoscopic medical visualization system is presented, which can be clinically used for diagnosis and surgical planning. The algorithms of direct volume rendering have been improved for realization with the programmable graphics hardware under PC environment. Local illumination, classification and non-polygonal iso-surface rendering are also incorporated into the system in appropriate consideration of both high-quality rendering and real-time interaction. The medical visualization system has been applied to the neurosurgical and orthopedic planning and the effectiveness has been clinically proved.

Objective: To investigate the buffer capacity of insoluble plaque mass including bacteria and glucans matrix., Methods: Plaque samples (starved or incubated 1 h with 10% sucrose), Streptococcus mutans (S. mutans) mass, and insoluble/soluble glucans were titrated with 1 mmol/L HCl. Meanwhile, the density of bacteria was counted and related to buffer capacity., Results: The bacteria density had significant effects on acid buffer capacity in dental plaque, but the effect reduced with consuming sugar. S. mutans mass with no sucrose incubating contributed to the buffer capacity of (0.609 +/- 0.202) mmol/L, and S. mutans mass with 2% sucrose had only the buffer capacity of (0.099 +/- 0.047) mmol/L. In the mean time, glucans had no effect on acid buffering (0.028 - 0.032 mmol/L)., Conclusions: The bacteria including S. mutans may be the main contributor to acid buffering in plaque solid.

Objective: To develop a computer assisted CT scanning system for 3D dental cast measurement and to study its reliability., Methods: 20 dental stone casts were scanned by helical CT and captured a series digital sliced radiographs of them. The program which was developed by Visual C 6.0 language and run under the Windows surroundings rebuilt the 3D graphics and measured the coordinate of the dental cast. These dental casts were scanned and measured to test the reliability of the system, contrasting with manual measurement., Results: There was no significant difference between 3D CT scanning and manual measurement (P > 0.05)., Conclusion: The system is a valuable computer assisted system for clinical diagnosis and treatment of malocclusion.

We put forward an image rendering system based on pipeline framework for processing and displaying medical images. Compared to original computer graphics algorithms divided into volume rendering and surface rendering, this framework can effectively comprehend methods of computer graphics and image processing, import some new concepts such as vertex buffer, pixel buffer and texture buffer. We implement Shaded Surface Display, Maximum Intensity Projection, Digitally Reconstructed Radiography, Multi planar Reformation, Curved Planar Reformation and Interactive Virtual Endoscopy in our new developed PACS image system.