Abstract:Objective To investigate the effect of propofol on brain regions at different sedation levels and the association between changes in brain region activity and loss of consciousness using blood oxygen level-dependent functional magnetic resonance imaging (BOLD-fMRI) and bispectral index (BIS) monitoring.Methods Forty-eight participants were enrolled at Peking Union Medical College Hospital from October 2011 to March 2012 and randomly assigned to a mild or a deep sedation group using computer- generated random numbers. Preliminary tests were performed a week prior to scanning to determine target effect site concentrations based on BIS and concomitant Observer’s Assessment of Alertness/Sedation scores while under propofol. Within one week of the preliminary tests where propofol dose-response was established, BOLD-fMRI was conducted to examine brain activation with the subject awake, and with propofol infusion at the sedation level.Results Mild propofol sedation inhibited left inferior parietal lobe activation. Deep sedation inhibited activation of the left insula, left superior temporal gyrus, and right middle temporal gyrus. Compared with mild sedation, deep propofol sedation inhibited activation of the left thalamus, precentral gyrus, anterior cingulate, and right basal nuclei.Conclusion Mild and deep propofol sedation are associated with inhibition of different brain regions, possibly explaining differences in the respective loss of consciousness processes.
Abstract:Objective To evaluate the outcomes of T3a prostate cancer with unfavorable prognostic factors treated with permanent interstitial brachytherapy combined with external radiotherapy and hormone therapy.Methods From January 2003 to December 2008, 38 patients classified as T3a prostate cancer with unfavorable prognostic factors were treated with trimodality therapy (brachytherapy + external radiotherapy + hormone therapy). The prescription dose of brachytherapy and external radiotherapy were 110 Gy and 45 Gy, respectively. The duration of hormone therapy was 2-3 years. The endpoints of this study included biochemical failure-free survival (BFFS), distant metastasis-free survival (DMFS), cancer-specific survival (CSS), and overall survival (OS). Survival curves were calculated using the Kaplan-Meier method. The Log-rank test was used to identify the prognostic predictors for univariate analysis.Results The median follow-up was 71 months. The serum pre-treatment prostate-specific antigen (PSA) level ranged from 10.0 to 99.8 ng/ml (mean 56.3 ng/ml), the Gleason score ranged from 5 to 9 (median 8), and the percentage of positive biopsy cores ranged from 10% to 100% (mean 65%). The 5-year BFFS, DMFS, CSS, and OS rates were 44%, 69%, 82%, and 76%, respectively. All biochemical failures occurred within 40 months. The percentage of positive biopsy cores was significantly correlated with BFFS, DMFS, and OS (all P=0.000), and the Gleason score with DMFS (P=0.000) and OS (P=0.001).Conclusions T3a prostate cancer with unfavorable prognostic factors presents not so optimistic outcome. Hormone therapy should be applied to prolong the biochemical progression-free or metastasis-free survival. The percentage of positive biopsy cores and the Gleason score are significant prognostic factors.
Abstract:Objective To explore the features of various mediastinal lymphadenopathies using computed tomography perfusion (CTP).Methods CTP parameters (CTPs) of the selected mediastinal nodes from 59 patients with pathology-proven malignant lymph nodes and of those from 29 patients with clinically diagnosed or pathology-proven inflammatory lymphadenopathies were collected. Patients were divided into subgroups by etiology and phase of primary disease, including different pathological malignant nodes and diverse inflammatory nodes. CTPs were defined as blood flow (BF), blood volume (BV), mean transit time (MTT), permeability (PMB), and time to peak (TTP). Differences of CTPs were compared between malignant and benign nodes, and among subgroups, respectively.Results In the mediastinum, no significant differences of CTPs were found between malignant and benign groups (all P>0.05), the same for subgroups of malignant nodes (all P>0.05). Acute lymphadenitis had higher BF and BV than chronic inflammatory, lymphoid tuberculosis, sarcoidosis and malignant nodes. The BF of malignant nodes was markedly slower than that of acute lymphadenitis (P=0.01), but faster than chronic inflammatory nodes (P=0.04) and sarcoidosis (P=0.03), with no significant difference compared with lymphoid tuberculosis. Pneumonia-complicated lymphoid tuberculosis showed the longest MTT while sarcoidosis displayed the shortest MTT, and inflammatory nodes, lymphoid tuberculosis without complicated pneumonia and malignant nodes had moderate MTT.Conclusion CTPs show promising potential in distinguishing various lymphadenopathies in the mediastinum, but more studies are needed to improve their specificity.
Abstract:Objective To study the changes of biomarkers in cerebrospinal fluid (CSF) in cerebral amyloid angiopathy (CAA) dementia and Alzheimer’s disease.Methods Levels of amyloid protein β (Aβ42, Aβ40) and phosphorylated Tau-protein (P-tau) in CSF and ratio of Aβ42/Aβ40 were tested in 5 cases with CAA dementia and 20 cases with Alzheimer’s disease collected at Peking Union Medical College Hospital from December 2001 to March 2011.Results The levels of Aβ42, Aβ40, and P-tau in CSF and ratio of Aβ42/Aβ40 were (660.4±265.2) ng/L, (7111.0±1033.4) ng/L, (71.8±51.5) ng/L, and 0.077±0.033, respectively in CAA dementia and (663.6±365.6) ng/L, (5115.0±2931.1) ng/L, (47.7±38.8) ng/L, and 0.192±0.140, respectively in Alzheimer’s disease patients. There were no statistically significant differences between CAA dementia and Alzheimer’s disease in terms of these CSF biomarkers (all P>0.05).Conclusion Measurements of CSF biomarkers may not be helpful in differential diagnosis of CAA and Alzheimer’s disease.
Abstract:Objective To evaluate the incidence of two-rooted mandibular premolar morphology using full-mouth periapical film series in a Chinese population, with particular emphasis on bilateral incidence, so as to provide a clinical anatomical basis for root canal treatment in mandibular premolars.Methods A total of 2015 patients who underwent dental treatment and had full mouth periapical radiographs at the Peking University School of Stomatology from April 2011 to April 2012 were enrolled in this study. Three experienced dentists reviewed the patients’ periapical films and classified the root morphology of mandibular premolars bilaterally. The incidence of unilateral and bilateral double roots were recorded and calculated, including confirmed and suspected bucco-lingual root types.Results In terms of the morphology of two-rooted mandibular first premolars, of the 2015 cases with complete root formation, two-rooted first premolars were detected in 120 cases, with a total number of 159 teeth. According to the number of teeth, the overall incidence of double roots was 4.03% (159/3972). In terms of the morphology of two-rooted mandibular second premolars, of the 2015 cases with complete root formation, two-rooted second premolars were detected in 24 cases, with a total number of 33 teeth. According to the number of teeth, the overall incidence of double roots was 0.85% (33/3880).Conclusions The roots of mandibular premolars display specific morphological patterns. Based on a large sample, we observed and calculated not only the occurrence rate of bucco-lingual and mesio-distal double roots in first and second mandibular premolars, but also the incidence of unilateral or bilateral double roots within the same mandible. These findings could provide useful information on the anatomical structure of mandibular premolars for endodontic, prosthodontic and surgical procedures, and could improve the quality of treatment and reduce complications.
Abstract:In this article, the mechanism of inheritance behind inherited hearing loss and genetic susceptibilityin noise-induced hearing loss are reviewed. Conventional treatments for sensorineural hearing loss (SNHL), i.e. hearing aid and cochlear implant, are effective for some cases, but not without limitations. For example, they provide little benefit for patients of profound SNHL or neural hearing loss, especially when the hearing loss is in poor dynamic range and with low frequency resolution. We emphasize the most recent evidence-based treatment in this field, which includes gene therapy and allotransplantation of stem cells. Their promising results have shown that they might be options of treatment for profound SNHL and neural hearing loss. Although some treatments are still at the experimental stage, it is helpful to be aware of the novel therapies and endeavour to explore the feasibility of their clinical application.