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81.

Background

Microvascular decompression (MVD) has become a well-established surgical procedure for hemifacial spasm (HFS). Before surgery, it is essential to evaluate any possible deformity of the brainstem and establish the precise location of the offending vessels. In the present study of HFS patients we examined coronal sections taken by heavily T2-weighted MR cisternography in addition to routine axial sections, and assessed the usefulness of these images through comparison with intraoperative findings.

Methods

Eighty patients with HFS underwent preoperative coronal heavily T2-weighted MR cisternography before microvascular decompression surgery. Three neurosurgeons examined the preoperative axial and coronal MR images and evaluated vessel invagination into the brainstem. The usefulness of coronal sections was assessed statistically by the Mann-Whitney U test.

Results

Invagination of the offending vessel into the brainstem was observed in 24 cases (30.0%). In 19 patients, it was predicted preoperatively that compression of the flocculus and brainstem would be required in order to approach the offending vessels. Coronal MR cisternography was significantly more useful in cases with vessel invagination into the brainstem than in cases without invagination.

Conclusions

Coronal sections obtained by MR cisternography are able to demonstrate the severity of vessel invagination into the brainstem as well as revealing the presence of the offending vessel. This information is helpful for planning a suitable approach to the root exit zone.  相似文献   
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Background

It is crucial to identify risk factors for life prognosis after hepatitis C virus (HCV) eradication among patients with or without a high risk of liver cancer or complications.

Methods

This is a prospective, multicenter and observational study using the database of 1031 patients after HCV eradication by direct-acting antiviral agents (DAAs) to evaluate the development of hepatocellular carcinoma (HCC) and patients’ survival after a sustained virological response (SVR). The Cox proportional hazards regression model was used to estimate hazard ratios associated with HCC development and survival.

Results

AFP at SVR was significantly associated with HCC recurrence in the adjusted model. Liver fibrosis, Mac-2 binding protein glycosylation isomer (M2BPGi) at SVR and smoking status before treatment were positively associated with the development of HCC and M2BPGi was positively associated with HCC recurrence, although not reaching statistical significance. Among patients without a history of HCC, M2BPGi and estimated glomerular filtration rate (eGFR) at SVR were significantly associated with death after viral eradication [M2BPGi (HR 4.07, 95% CI 1.22, 13.57), eGFR (HR 0.97, 95% CI 0.94, 0.99)]. Strikingly, of 16 patients who died, among participants without a history of HCC, only two died of liver cancer associated with HCV, whereas 11 died of non-HCV- related cancer or cardiovascular diseases.

Conclusion

M2BPGi at SVR is a potential predictor for patients’ survival and a candidate biomarker for detecting individuals who are at greater risk of death due to cancer-related and unrelated to HCV, as well as cardiovascular diseases, after viral eradication.

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To evaluate peripheral neuropathy in patients with vibration syndrome, an examination was conducted of sensory nerve conduction velocity (SCV) in the digital segment of the median nerve in the middle finger and vibration perception threshold (VPT) at 125 Hz on the same middle fingertip. In addition, possible correlations were investigated between the two measurements. SCVs in the digital segment were measured by stimulating at the wrist electrically and recording from two pairs of electrodes in the finger. Fractionated SCVs were also measured in the palm-to-finger, wrist-to-palm, and elbow-to-wrist segments. The subjects were 52 patients with vibration syndrome and 40 healthy controls of similar age. SCVs in the digital segment and the wrist-to-palm segment were significantly slower in the patients than in the controls, and VPTs were higher in the patients. The strongest correlation of VPTs with SCVs among nerve segments measured was shown in the digital segment. With all increase in VPTs. SCVs in the digital segment tended to be slower, and slowed digital SCVs were encountered more frequently: 13% in VPTs below 5.0 dB and 56% in VPTs above 17.5 dB. Slowed digital SCVs were found in 43% of the patients and increased VPTs were encountered in 92%. © 1996 Wiley-Liss, Inc.  相似文献   
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Although dysplasia of the esophagus is thought to be the precursor lesion of esophageal squamous cell carcinoma (ESC), the sequence of genetic events during esophageal carcinogenesis is unclear. Using the polymerase chain reaction, we examined allelic losses at microsatellite loci in DNAs isolated from 106 lesions among 32 patients with ESC. Allelic losses on 3p or 17p occurred frequently even in dysplastic lesions (9 of 21 and 13 of 24 samples, respectively) including lesions with mild dysplasia (3p, 4 of 10 samples; 17p, 6 of 14 samples, respectively), and allelic losses on these chromosomal arms were also observed in cancerous tissues. We also detected allelic losses of the short and long arms of chromosome 9 at a low frequency in lesions with mild dysplasia and often in lesions with severe dysplasia and in intraepithelial cancers. Our results suggested that inactivation of tumor suppressor genes on 3p and 17p occurs at a very early stage of esophageal carcinogenesis and that genes on 9p and 9q are likely to play important roles in malignant changes. Comparison of the genetic alterations in precancerous dysplastic lesions with those in carcinomas supports the idea that ESC arises from the dysplastic lesion. Genes Chromosom Cancer 15:165–169 (1996). © 1996 Wiley-Liss, Inc.  相似文献   
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Non-alcoholic steatohepatitis (NASH) can cause liver cirrhosis and hepatocellular carcinoma (HCC), with cases increasing worldwide. To reduce the incidence of liver cirrhosis and HCC, NASH is targeted for the development of treatments, along with viral hepatitis and alcoholic hepatitis. Lactoferrin (LF) has antioxidant, anti-cancer, and anti-inflammatory activities. However, whether LF affects NASH and fibrosis remains unelucidated. We aimed to clarify the chemopreventive effect of LF on NASH progression. We used a NASH model with metabolic syndrome established using connexin 32 (Cx32) dominant negative transgenic (Cx32ΔTg) rats. Cx32ΔTg rats (7 weeks old) were fed a high-fat diet and intraperitoneally injected with dimethylnitrosamine (DMN). Rats were divided into three groups for LF treatment at 0, 100, or 500 mg/kg/day for 17 weeks. Lactoferrin significantly protected steatosis and lobular inflammation in Cx32ΔTg rat livers and attenuated bridging fibrosis or liver cirrhosis induced by DMN. By quantitative RT–PCR, LF significantly down-regulated inflammatory (Tnf-α, Il-6, Il-18, and Il-1β) and fibrosis-related (Tgf-β1, Timp2, and Col1a1) cytokine mRNAs. Phosphorylated nuclear factor (NF)-κB protein decreased in response to LF, while phosphorylated JNK protein was unaffected. These results indicate that LF might act as a chemopreventive agent to prevent hepatic injury, inflammation, and fibrosis in NASH via NF-κB inactivation.  相似文献   
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