伊文氏蓝染色对大鼠脑内肿瘤生物学标记方法的研究

目的研究在大鼠脑内肿瘤模型中生物学染色标记脑内肿瘤的方法。方法选择F344大鼠,移植体外培养的RG2胶质瘤细胞制作脑内肿瘤模型,移植18d后经大腿静脉注射伊文氏蓝(Evans blue,EB)染色肿瘤组织,探讨生物学染色对脑内肿瘤的标示作用和手术中对肿瘤和周围正常脑组织鉴别的意义。结果EB浓度在100mg/kg时,肿瘤组织染色成鲜明蓝色,同时大鼠的皮肤和所有器官都被染色成蓝色;当浓度低于10mg/kg时,仅染色肿瘤组织而皮肤和其他器官不被染色;肉眼可鉴别的最低静注浓度为1.25mg/kg。肿瘤组织的染色效果持续到静注后96h。血清中EB浓度在静注后3h内迅速减少,之后呈缓慢代谢过程,静注后24h减少到静注浓度的38%,静注后24h EB在血清和肿瘤组织中的浓度差达到最大值。染色后在手术显微镜下进行肿瘤切除手术操作较未染色对照组明显容易,手术后切片组织学观察肿瘤被完全切除。结论EB生物学染色标记脑内肿瘤效果可靠,手术中作为肿瘤的标示鉴别肿瘤和周围正常脑组织的界限有效。     

Residual monomers (TEGDMA and Bis-GMA) of a set visible-light-cured dental composite resin when immersed in water

Rods of a visible-light-cured dental composite resin were photo-polymerized and immersed in water at 37 degrees C for 7 days. The residual monomers (TEGDMA and Bis-GMA) trapped in the set composite and those eluted into water were analysed by gas-liquid chromatography. It became evident that minor amounts of the residual monomers dissolved in water, but that most residual monomers remained in the set composite. Extension of the irradiation period contributed to the significant reduction in the residual monomer level and its elution into water.     

Early sigmoid colon carcinoma developed from a pedunculated polyp

A 60‐year‐old man underwent routine colonoscopy, and was noted to have a pedunculated polyp in the sigmoid colon. The pathologic diagnosis was adenoma, and due to patient’s personal circumstances, the lesion was left untreated. The colonoscopic examination was repeated 4 years and 11 months later, to find that the polyp had transformed into an elevated lesion with irregularly depressed surface. The patient was diagnosed as having early sigmoid cancer, and underwent sigmoidectomy. The histologic examination of the excised specimen revealed well‐differentiated adenocarcinoma with invasion into the submucosal layer. Through studying the natural course of colon cancer, it has become known that the advanced cancers commonly develop from polyps with short pedicles (sessile polyps). This case represents an early sigmoid cancer developed from a pedunculated polyp, which differs from the current mainstream concept of ‘polyp‐cancer sequence of colon cancer.’     

Prognostic impact of calf muscle near-infrared spectroscopy in patients with a first episode of deep vein thrombosis

Summary. Background: The risk factors that affect the development of post‐thrombotic syndrome (PTS) are not fully recognized, and it is difficult to reliably predict which patients are likely to develop PTS in acute phase of deep vein thrombosis (DVT). Aims: To investigate changes in calf muscle deoxygenated hemoglobin (HHb) levels after DVT, and to determine the indicative parameters reflecting the progression of PTS. Methods: Seventy‐six consecutive patients with a first episode of unilateral DVT were prospectively enrolled. Clinical manifestations were categorized according to the CEAP (Clinical, Etiologic, Anatomical, and Pathophysiologic) classification, and the patients were divided into no‐PTS (C_0–3E_s,A_s,d,p,P_r,o) and PTS (C_4–6E_s,A_s,d,p,P_r,o) groups. Near‐infrared spectroscopy (NIRS) was used to measure calf muscle HHb levels at 6 months after diagnosis of DVT. The calf venous blood filling index (HHbFI) was calculated on standing, and the venous ejection index and the venous retention index (HHbRI) were then obtained after exercise. All patients were followed up for more than 24 months after the diagnosis of DVT. Results: Of 76 patients evaluated, 20 (26.3%) had PTS. The NIRS‐derived HHbFI and HHbRI were significantly increased in patients who developed PTS in comparison with those who did not (P = 0.04 and P = 0.0001, respectively). HHbRI was significantly increased in patients with iliofemoral DVT in comparison with patients with calf DVT (P = 0.041). An optimal cut‐off point of 2.9 for HHbRI showed the strongest ability to predict the development of PTS, with a sensitivity of 100% and a specificity of 82.1%. Conclusions: HHbRI as measured by NIRS is significantly increased in patients with iliofemoral DVT as compared with those with calf DVT. Furthermore, HHbRI > 2.9 is a strong predictor of the development of PTS at 6 months.     

A quantitative assessment of serum chylomicron by light scattering intensity: Application to the intestinal fat absorption test

A novel fat absorption test to clarify the malabsorption syndrome was developed using a micronephelometric technique and compared with the classic conventional technique using ¹³¹I-triolein. An integrity of time-sequential light scattered from chylomicron-related turbidity in serum was determined between 0 and 300 min after butter fat load, being expressed in terms of the light scattering intensity (LSI). A good correlation was obtained between LSI and the serum level of chylomicron-triglyceride determined by an ultracentrifugation technique (r=0.819, P < 0.001). The maximal LSI was consistently observed at 180 min after administration of a test meal in the normal group (n= 39), whereas the malabsorption syndrome group (n= 35) was distinctly different and could be further classified according to four patterns of LSI changes. In addition, an inverse correlation was found between this fat absorption test and the ¹³¹I-triolein absorption test. It was concluded that the micronephelometric technique which does not use a radionuclide is advantageous in its simple and safe evaluation of fat malabsorption syndrome.     

Proliferative fasciitis of the forearm: Case report with immunohistochemical, ultrastructural and DNA ploidy studies and a review of the literature

A case of prollferative fasclitis arising In the left forearm of a 56-year-old man was examined. The lesion was preceded by blunt trauma, measured 1.5 times 1.3 times 1.0 cm, was poorly circumscribed and appeared white to light gray on the cut surface. Light microscopic examinations revealed that spindle cells and giant cells with one or two nuclei and abundant basophllic cytoplasm ware arranged without any organized patterns In collagenous stroma. Ultrastructurally, well-developed rough endoplasmic reticulum separated by varying amounts of fine to course fibrillar materials was detected in the giant cells. Only vimentin lmmunoreactivity was detected In both spindle and gtant cells. The Ki-67 labeling Index of spindle cells was 35% but that of giant cells was less than 5%, and this reflects the quiescent or slow-growing features of these giant cells in proliferative fasclitis. DNA content of the calls, which was examined by Image cytometry, demonstrated diploidy In both spindle (DNA Index = 1.01) and glant (DNA Index = 1.09) calls.     

Studies on dental high-speed cutting of commercial pure titanium (Ti) and free-machining titanium (DT-2F)

summary Some dental prostheses are formed by machining. The purpose of this study was to evaluate the dental high-speed cutting behaviour of free-machining titanium (Ti), the ease in cutting of which is metallurgically improved. Weight-load cutting tests were performed on commercial pure Ti and free-machining Ti, using a diamond point and a carbide burr. It became evident that the cutting effectiveness of two rotary cutting instruments on free-machining Ti was superior to that on commercial pure Ti due to the formation of accelerated cut debris. Cutting of free-machining Ti resulted in less damage of the carbide burr, compared with the cutting of commercial pure Ti. These results suggest that free-machining Ti is a suitable workpiece for dental Ti-based machined prostheses.     

Dental high-speed cutting of four cast alloys

The purpose of this study was to evaluate dental high-speed cutting behaviour of four cast alloys, namely Ag-Pd-Cu-Au alloy, Ag-Zn-In-Sn alloy, Ni-Cr alloy and Ti. Weight-load cutting tests were conducted on four cast alloys, using two rotary cutting instruments, namely a diamond point and a carbide bur, both driven by an air-turbine handpiece. While the constant transverse load of 80 g was applied on the workpiece for 5s, the handpiece speed was measured during cutting as well as the volume of workpiece removal which took place. The cutting tests were repeated 10 times. We found that the cutting volumes of soft Ag-Pd-Cu-Au alloy and Ag-Zn-In-Sn alloy were considerably larger than those of hard Ni-Cr alloy and Ti. It was also clarified that the cutting effectiveness of the carbide bur was generally superior to that of the diamond point. With continuing use, however, the cutting capability of the carbide bur tended to decline while that of the diamond point remained quasi-constant.