The influence of the segmentation process on 3D measurements from cone beam computed tomography-derived surface models

To compare the accuracy of linear and angular measurements between cephalometric and anatomic landmarks on surface models derived from 3D cone beam computed tomography (CBCT) with two different segmentation protocols was the aim of this study. CBCT scans were made of cadaver heads and 3D surface models were created of the mandible using two different segmentation protocols. A high-resolution laser surface scanner was used to make a 3D model of the macerated mandibles. Twenty linear measurements at 15 anatomic and cephalometric landmarks between the laser surface scan and the 3D models generated from the two segmentation protocols (commercial segmentation (CS) and doctor’s segmentation (DS) groups) were measured. The interobserver agreement for all the measurements of the all three techniques was excellent (intraclass correlation coefficient 0.97–1.00). The results are for both groups very accurate, but only for the measurements on the condyle and lingual part of the mandible, the measurements in the CS group is slightly more accurate than the DS group. 3D surface models produced by CBCT are very accurate but slightly inferior to reality when threshold-based methods are used. Differences in the segmentation process resulted in significant clinical differences between the measurements. Care has to be taken when drawing conclusions from measurements and comparisons made from different segmentations, especially at the condylar region and the lingual side of the mandible.     

安氏Ⅱ类亚类错畸形的病因及其矫治

安氏Ⅱ类亚类错畸形是临床中较为常见的一种错畸形,是在临床治疗中最为复杂和困难的错类型之一。临床中可以通过多种方法,来协调以使双侧达到良好磨牙关系。正畸医师应根据患者年龄、错的严重程度、合并的错类型、患者配合程度等选择不同的方法,以达到最佳效果。本文就近年来对安氏Ⅱ类亚类错畸形的病因、临床表现及治疗方法等的相关研究作一综述。     

Evaluation of renal biopsies in type 2 diabetic patients with kidney disease: a clinicopathological study of 216 cases

Objectives

The outcome and the therapy of patients with diabetes mellitus (DM), diabetic nephropathy (DN), and non-diabetic renal disease (NDRD) are quite different, so the differential diagnosis is of considerable importance. To evaluate the usefulness of renal biopsy in type 2 diabetic patients, we examined the relationship between the clinical parameters and the histopathological findings in different age groups.

Methods

Renal biopsy specimens and clinical and laboratory data from 216 patients with type 2 DM were evaluated. According to their age, three groups were defined: 17–35 years (group I), 36–59 years (group II), and more than 60 years (group III).

Results

The study showed that, beside the duration of diabetes, other clinical parameters were not significantly different between the three groups. Chronic nephritic syndrome was the most common clinical manifestation in group I (44.1 %) and in group II (34.0 %). Among patients in group III, we found a high prevalence of chronic renal failure (34.3 %) and nephrotic syndrome (28.6 %). Consistent with the clinical manifestations, IgA nephropathy was the most common pathologic finding in group I (29.4 %) and in group II (34.7 %), whereas the most frequent abnormalities in group III were membranous nephropathy (25.7 %) and tubulointerstitial lesions (14.3 %). Overall, among these patients, 14 cases were diagnosed with DN (6.5 %), 179 with NDRD (82.9 %), while 23 had concurrent DN and NDRD (10.7 %).

Conclusions

Our results indicated that the clinical manifestations and pathologic findings in type 2 diabetic patients in different age groups have different features. This study emphasized the usefulness of renal biopsy for determining the pattern of renal damage and thus for the overall management of type 2 diabetic patients.     

Myelin specific cells infiltrate MCAO lesions and exacerbate stroke severity

Although inflammatory responses increase stroke severity, the role of immune cells specific for central nervous system (CNS) antigens remains controversial. Disruption of the blood–brain barrier (BBB) during stroke allows CNS antigens to leak into the peripheral circulation and enhances access of circulating leukocytes to the brain, including those specific for CNS antigens such as myelin oligodendrocyte glycoprotein (MOG) that can induce experimental autoimmune encephalomyelitis (EAE). We here demonstrate for the first time that myelin reactive splenocytes specific for MOG transferred into severe combined immunodeficient (SCID) mice can migrate into the infarct hemisphere of recipients subjected to 60 min middle cerebral artery occlusion (MCAO) and 96 h reperfusion; moreover these cells exacerbate infarct volume and worsen neurological deficits compared to animals transferred with na?ve splenocytes. These findings indicate that autoimmunity in the CNS can exert detrimental injury on brain cells and worsen the damage from ischemic stroke.     

External beam radiation therapy is safe and effective in treating primary pulmonary amyloidosis

The aim of the prospective study was to explore the safety and effectiveness of external beam radiation therapy (EBRT) in three patients with biopsy proven primary pulmonary amyloidosis, including two tracheobronchial amyloidosis patients and one primary parenchymal amyloidosis patient. All three patients were treated to 24 Gy in 12 fractions utilizing CT simulation and 3-D planning. All three patients had significant improvement in clinical symptoms, radiological imaging as well as pulmonary function tests. The improvement in the clinical symptoms was evident in 2 days. Toxicities related to EBRT were not observed during the follow-up range from 42 to 54 months. EBRT to 24 Gy was safe and effective in the three patients with primary pulmonary amyloidosis, and resulted in rapid relief of pulmonary symptoms.     

Survival from digestive cancer in emerging countries in Asia and Africa

The incidence of digestive cancer, including cancer of the esophagus, stomach, colon, and liver, is analyzed in developing and less developed countries in Africa, Asia, the Caribbean, and Latin America. The analysis is based on cancer registries for observed values, on a recent monograph published at International Agency for Research on Cancer and on the GLOBOCAN 2008 database for estimations. For all tumor sites analyzed, the incidence is lower in these countries than in developed countries of Europe, North America, and Japan. The 5-year relative survival from digestive cancer is also lower. In developing countries, there is room for prevention of cancer burden through lifestyle interventions and through improved early detection of cancer.