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1.
OBJECTIVE: Clinical, radiographic, and microbiologic changes in deep caries lesions were assessed after incomplete carious dentin removal and tooth sealing. METHOD AND MATERIALS: Thirty-two teeth with deep caries lesions were studied. Treatment consisted of incomplete excavation of the demineralized dentin, application of calcium hydroxide, and sealing for a 6- to 7-month period. The color and consistency of the dentin were clinically assessed. Differences in radiographic density were assessed by digital image subtraction. Microbiologic samples were obtained from the demineralized dentin before the temporary sealing and after the experimental period. The samples were cultivated on blood agar under aerobic and anaerobic conditions, in Mitis Salivarius agar, and Rogosa selective Lactobacillus agar. RESULTS: Two cases were lost during the study; one presented pulpal necrosis. In the other case, there was pulpal exposure during removal of provisional sealing. In all teeth, the initial demineralized dentin was soft and wet; one lesion was yellow, 21 were light brown, and eight were dark brown. After treatment, the dentin was dry, and 80.00% of specimens were hard, 16.67% were leathery, and 3.33% remained soft. The dentin was light brown in five teeth and dark brown in 25. There was a statistically significant mean difference in radiographic density (pixel intensity), 88.77 +/- 7.02 in the control areas and 94.66 +/- 6.75 in the test areas. The counts of anaerobic and aerobic bacteria, lactobacilli, and Streptococci mutans had decreased significantly by the end of treatment. CONCLUSION: Incomplete removal of carious dentin and subsequent tooth sealing resulted in the arrest of the lesions, suggesting that complete dentinal caries lesion removal is not essential to the control of caries lesions.  相似文献   
2.
Hypomorphic mutations of the MRE11 gene are the hallmark of the radiosensitive ataxia-telangiectasia-like disorder (ATLD). Here, we describe a new family with two affected siblings, ATLD5 and ATLD6, now aged 37 and 36, respectively. They presented with late onset cerebellar degeneration slowly progressing until puberty and absence of telangiectasias, and were cancer-free. Both patients were wild-type for ATM and NBS1, but compound heterozygotes for MRE11 gene mutations [1422C-->A, T481K; 1714C-->T, R571X]. The 1422C-->A allele was inherited from the mother, whereas the 1714C-->T, allele paternally inherited, was apparently null as a result of nonsense-mediated mRNA decay (NMD). Interestingly, the 1714C-->T mutation is the same as previously identified in an unrelated English ATLD family (probands ATLD3 and ATLD4), suggesting an important role for NMD in saving potentially lethal mutations. Lymphoblastoid cell lines (LCLs) derived from ATLD5 and ATLD6 were normal for ATM, but defective for Mre11, Rad50 and Nbs1 (the MRN complex) protein expression. Their response to gamma-radiation was abnormal, as evidenced by the enhanced radiosensitivity, attenuated autophosphorylation of ATM-S1981 and phosphorylation of the ATM targets p53-S15 and Smc1-S966, failure to form Mre11 nuclear foci and defective G1 checkpoint arrest. The fibroblasts, but not LCLs, from ATLD5 and ATLD6 showed an impaired ATM-dependent Chk2 phosphorylation. These findings further underscore the interconnection between ATM activity and MRN function, which rationalizes the clinical similarity between ataxia-telangiectasia (A-T) and ATLD.  相似文献   
3.
Neurosurgical Review - Recently, endoscopic transsphenoidal transclival approaches have been developed and their role is widely accepted for extradural pathologies. Their application to intradural...  相似文献   
4.
Endoscopic microsurgery in herniated cervical discs   总被引:14,自引:0,他引:14  
The purpose of this study was to make public our results using endoscopic microsurgery in herniated cervical discs. This technique allows us to avoid complications due to conventional exposure, as is the case in traditional approaches. This study was carried out from January 1991 to January 1998. One hundred and seventy-one patients should have undergone traditional surgery for 296 herniated cervical discs. They were, instead, treated by using endoscopic microsurgical techniques. In 273 herniations the surgical procedure was performed by a paramidline right anterior approach, and in 23 herniations by a paramidline posterior approach, with a working sleeve of 4.6 mm outer diameter in both cases. In the anterior approach the tube was firmly placed against the anterior longitudinal ligament and the edge of the anterior part of the vertebral bodies. The neurovascular structures were placed lateral to the working sleeve and the visceral structures were placed medial to the working sleeve. Then, under endoscopic coaxial control, removal of the herniated part was performed, through the intervertebral discs, with microsurgical instruments. In the posterior approach, the tube was placed instead between the inferior and superior lamina, then under the nerve root up to the herniation, which was removed. This posterior approach was used only in the lateral disc herniations. There were no incidents or major complications following these operations. After one month the success rate was 94.7%, after three months 95.9%, after six months 96.4% and after one year 97%. There were no cases of relapse during the follow-up period of these patients. This study suggests that for herniated cervical discs, the endoscopic microsurgical technique is an extremely advantageous and safe method. Moreover, longer follow-up periods and an increased number of patients treated with this procedure should further confirm the usefulness of this technique.  相似文献   
5.
The authors report a case of follicular thyroid cancer in "hot nodule" with micronodular synchronous lung metastases. The treatment consisted in TT associated with radioiodine therapy at the dose of 170 mCi with remission of cancer after six months of follow-up. Follicular variant is a prognostic unfavorable factor such as synchronous or metachronous pulmonary metastases. In those patients prognostic unfavorable variants are also age over 40 years, a poor radiofixation capacity, and a lesion of diameter up 1 cm. A strictly instrumental follow-up is mandatory to obtain diagnosis in a subclinical stage. In such cases the radiometabolic therapy agree to a remission of cancer with high survival after many years. TT yet represents a "minimal" surgical treatment for an accurate radioisotopic diagnosis.  相似文献   
6.
7.
The clinical features of 'cryptogenic' chronic liver disease and the prevalence of antibody to hepatitis C virus (HCV) in serum have been investigated in 33 Italian children (mean age 5 years). The diagnosis was based on the persistence of increased alanineaminotransferase values for longer than 6 months after the exclusion of biliary diseases, of extra-hepatic causes of hypertransaminasemia, of infection with known hepatotropic viruses and of autoimmune or metabolic disorders. Five patients had been transfused early in life, three had undergone surgery and one girl's mother had had acute non-A, non-B hepatitis during pregnancy. The remaining patients had no history of overt parenteral exposure. At presentation only 11 patients were symptomatic, the others had been referred after a check-up for intercurrent diseases. Liver histology performed in 21 cases showed persistent or mild active hepatitis in 18 cases and severe hepatitis or cirrhosis in three cases. Anti-HCV antibodies were found in 48% of the cases, including 88% with obvious exposure and 33% of the remaining cases. During a mean follow-up period of 5 years (range 1-14 years) only 11% of the cases achieved sustained biochemical remission, although none developed signs of liver failure. There was no significant difference in the clinical features and outcome of the disease between anti-HCV-positive and -negative patients. The results of this study suggest that HCV is implicated in most cases of 'cryptogenic' chronic liver disease observed in Italian children with a history of parenteral exposure and in at least one-third of the cases without overt exposure.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
8.
The long-term changes of liver stiffness (LS) in patients who achieve viral clearance after direct-acting anti-HCV therapy remain undefined. We conducted a multicentre prospective study to investigate this aspect. Patients with HCV infection treated with DAAs were enrolled from six Italian centres; they underwent clinical, biochemical, ultrasound and transient elastography evaluations before treatment (T0), 12 weeks (SVR12) and 24 months (T24) after the end of therapy. Among the 516 consecutive patients enrolled, 301 had cirrhosis. LS significantly decreased from T0 to SVR (14.3 vs 11.1 kPa, p = .002), with a progressive reduction until T24 (8.7 kPa, p < .001). However, only patients with steatosis and those who developed HCC did not experience a late improvement in LS. Multivariate analysis of baseline and follow-up variables identified steatosis as the only independent predictor of failure of LS improvement (OR 1.802, p = .013). ROC curve analysis of the association of LS with the risk of developing HCC showed that SVR12 ≥14.0 kPa had the highest accuracy (sensitivity 82%, specificity 99%; AUC: 0.774). Multivariate analysis revealed that LS was the only variable independently associated with an increased risk of developing HCC (OR 6.470, p = .035). Achieving an SVR was associated with a progressive, long-term decline of LS, suggesting a late improvement in liver fibrosis, besides the resolution of inflammation. Fatty liver and the development of HCC interfered with late reduction of LS. Patients with an LS ≥14 kPa at 12 weeks after the end of treatment were at higher risk for developing HCC.  相似文献   
9.
10.

Objective

To analyze the efficacy and safety of cortical and subcortical electrical stimulation CSES and awake surgery to approach purely subcortical tumors in highly functional locations, particularly in guiding the choice of the best transcortical path.

Patients and methods

Prospective analysis of the surgical, neurological, and radiological outcome of patients harboring supratentorial, subcortically located brain tumors or vascular malformations who are operated on through awake surgery and CSES. Functional magnetic resonance (fMRI; either sensory-motor or language, based on the location) was performed in order to confirm the proximity to functional cortical areas. Major white matter tracts were investigated by MRI diffusion tensor fiber tracking (DTI-ft). The Rankin modified score was chosen to express the pre and postoperative functional neurological status. Immediate postoperative MRI was used to evaluate the extent of resection.

Results

Seventeen patients were selected. The main distance of the tumors from the cortical surface was 18.2 mm (range 9–48 mm). Neuronavigation was used to show the most direct route to the tumor (transsulcal or transgyral), but CSES was fundamental to adapt the surgical corridor to the functional topography both cortically and subcortically. If the transgyral route was chosen, CSES helped to detect a non-eloquent area. When a transsulcal route was preferred, CSES documented the presence or absence of function in the deep sulcus. The transient postoperative morbidity was 76.4%, but at last follow-up (range 4–20 months), all the patients regained preoperative status and 2 improved. Postoperative MRI demonstrated complete resection in all cases.

Conclusions

Approaching purely subcortical tumors requires microsurgical skills, but in eloquent areas, functional topography monitoring is mandatory to allow safe surgery. CSES in an awake patient is a method that produces very good results in terms of resection and neurological outcome.  相似文献   
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