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Introduction: Systemic lupus erythematosus (SLE) is a prototypic autoimmune disorder with a variable clinical course, ranging from mild to severe forms. It mainly occurs in women, especially those of fertile age. The aim of the study was to systematically analyze the associations of perinatal disease activity with adverse outcomes of Chinese patients with SLE and their offspring. Material and methods: Data of prenatal SLE patients and healthy pregnant woman admitted to our hospital during the period October 2001 to January 2018 were retrospectively collected, and the status of offspring of SLE patients was followed up in March 2020. Disease activity was evaluated by SLE disease activity index 2000 (SLEDAI-2k), and those with scores > 6 were defined as having active disease. Results: In total, 198 deliveries of 194 SLE patients and 199 deliveries of healthy women were documented. Maternal and fetal adverse outcomes occurred in 74 (37.4%) and 90 (45.5%) deliveries of SLE patients, respectively, which were significantly higher than those of healthy subjects. Among SLE patients, the active group had higher rates of gestational hypertension (p < 0.001), preeclampsia/eclampsia (p < 0.001), low birth weight (p < 0.001), premature birth (p < 0.001) and fetal growth restriction (FGR) (p < 0.01) than the inactive group. Multivariate logistic analysis revealed that perinatal renal activity was associated with gestational hypertension (OR = 4.43, p < 0.001), preeclampsia/eclampsia (OR = 9.14, p < 0.001), low birth weight (OR = 2.24, p < 0.05) and premature birth (OR = 4.20, p < 0.001). Compared with the general population, offspring of SLE patients had relatively high rates of eczema (50/142, 35.2%) and congenital heart disease (6/142, 4.2%), which were irrelevant to perinatal disease activity, but related to specific antibodies. Conclusions: For perinatal women with SLE, renal activity is associated with a variety of adverse pregnancy outcomes. However, maternal perinatal disease activity does not seem to affect the growth of their offspring. [ABSTRACT FROM AUTHOR]

Objective: Recent research has highlighted the insula as a critical hub in human brain networks and the most susceptible region to subjective cognitive decline (SCD). However, the changes in functional connectivity of insular subregions in SCD patients remain poorly understood. The present study aims to clarify the altered functional connectivity patterns within insular subregions in individuals with SCD using resting-state functional magnetic resonance imaging (rs-fMRI). Methods: In this study, we collected rs-fMRI data from 30 patients with SCD and 28 healthy controls (HCs). By defining three subregions of the insula, we mapped whole-brain resting-state functional connectivity (RSFC). We identified several distinct RSFC patterns of the insular subregions. Specifically, for positive connectivity, three cognitive-related RSFC patterns were identified within the insula, suggesting anterior-to-posterior functional subdivisions: (1) a dorsal anterior zone of the insula that shows RSFC with the executive control network (ECN); (2) a ventral anterior zone of the insula that shows functional connectivity with the salience network (SN); and (3) a posterior zone along the insula that shows functional connectivity with the sensorimotor network (SMN). Results: Compared to the controls, patients with SCD exhibited increased positive RSFC to the sub-region of the insula, demonstrating compensatory plasticity. Furthermore, these abnormal insular subregion RSFCs are closely correlated with cognitive performance in the SCD patients. Conclusion: Our findings suggest that different insular subregions exhibit distinct patterns of RSFC with various functional networks, which are affected differently in patients with SCD. [ABSTRACT FROM AUTHOR]

Objective: To explore the value of multiparametric magnetic resonance imaging (MRI) radiomics in the preoperative prediction of isocitrate dehydrogenase (IDH) genotype for gliomas Methods: The preoperative routine MRI sequences of 114 patients with pathologically confirmed grade II-IV gliomas were retrospectively analysed. All patients were randomly divided into training cohort(n=79) and validation cohort (n=35) in the ratio of 7:3. After feature extraction, we eliminated covariance by calculating the linear correlation coefficients between features, and then identified the best features using the F-test. The Logistic regression was used to build the radiomics model and the clinical model, and to build the combined model. Assessment of these models by subject operating characteristic (ROC) curves, area under the curve (AUC), sensitivity and specificity. Results: The multiparametric radiomics model was built by eight selected radiomics features and yielded AUC values of 0.974 and 0.872 in the training and validation cohorts, which outperformed the conventional models. After incorporating the clinical model, the combined model outperformed the radiomics model, with AUCs of 0.963 and 0.892 for the training and validation cohorts. Conclusion: Radiomic models based on multiparametric MRI sequences could help to predict glioma IDH genotype before surgery. [ABSTRACT FROM AUTHOR]

Objective: The aim of this study is to investigate the value of ultrasound combined with computed tomography (CT) in identifying early low-grade appendiceal mucinous neoplasm and appendicitis. Methods: Patients with early low-grade appendiceal mucinous neoplasm and appendicitis from September 2017 to September 2021, including 40 patients with low-grade appendiceal mucinous neoplasm and 40 patients with appendicitis, were collected in this study. Clinical data as well as ultrasound and CT findings of all patients were retrospectively analyzed. Univariate and multivariate logistic regression analyses were applied to establish the ultrasound model, the CT model, and the combined model. Results: The nomogram showed that specific characteristics of CT were dilated appendiceal diameter and clear surrounding fat space in the low-grade appendiceal mucinous neoplasm and that specific characteristics of ultrasound were thin or clear layer appendix wall and flocculent echo in the appendix cavity. These four features were used to construct a nomogram for predicting early low-grade appendiceal mucinous neoplasm, and the area under the curve value was 0.839. Conclusion: Ultrasound combined with CT for diagnosis of early low-grade appendiceal mucinous neoplasm has a significant value; when found significantly dilated appendix in the lower right abdomen, with thin wall, wall calcification, clear surrounding fat space, and progressive enhancement, especially nonspecific symptoms similar to appendicitis, the physician should timely consider the possibility of low-grade appendiceal mucinous neoplasm. [ABSTRACT FROM AUTHOR]

Background/Objective: Early recurrence (ER) affects the long-term survival prognosis of patients with hepatocellular carcinoma (HCC). Many previous studies have utilized CT/MRI-based radiomics to predict ER after radical treatment, achieving high predictive value. However, the diagnostic performance of radiomics for the preoperative identification of ER remains uncertain. Therefore, we aimed to perform a meta-analysis to investigate the predictive performance of radiomics for ER in HCC. Methods: A systematic literature search was conducted in PubMed, Web of Science (including MEDLINE), EMBASE and the Cochrane Central Register of Controlled Trials to identify studies that utilized radiomics methods to assess ER in HCC. Data were extracted and quality assessed for retrieved studies. Statistical analyses included pooled data, tests for heterogeneity, and publication bias. Meta-regression and subgroup analyses were performed to investigate potential sources of heterogeneity. Results: The analysis included fifteen studies involving 3,281 patients focusing on preoperative CT/MRI-based radiomics for the prediction of ER in HCC. The combined sensitivity, specificity, and area under the curve (AUC) of the receiver operating characteristic were 75% (95% CI: 65-82), 78% (95% CI: 68-85), and 83% (95% CI: 79-86), respectively. The combined positive likelihood ratio, negative likelihood ratio, diagnostic score, and diagnostic odds ratio were 3.35 (95% CI: 2.41-4.65), 0.33 (95% CI: 0.25-0.43), 2.33 (95% CI: 1.91-2.75), and 10.29 (95% CI: 6.79-15.61), respectively. Substantial heterogeneity was observed among the studies (I²=99%; 95% CI: 99-100). Meta-regression showed imaging equipment contributed to the heterogeneity of specificity in subgroup analysis (P= 0.03). Conclusion: Preoperative CT/MRI-based radiomics appears to be a promising and non-invasive predictive approach with moderate ER recognition performance. [ABSTRACT FROM AUTHOR]

Background: Patient-specific quality assurance (PSQA) is an indispensable and essential procedure in radiotherapy workflow, and several studies have been done to develop prediction models based on the conventional C-arm linac of single-layered multileaf collimator (MLC) with machine learning (ML) and deep learning techniques to predict PSQA results and improve efficiency. Recently, a newly designed O-ring gantry linac "Halcyon" equipped with unique jawless stacked-and-staggered dual-layered MLC was released. However, few studies have focused on developing PSQA prediction models for this novel dual-layered MLC system. Purpose: To evaluate the performance of ML to predict PSQA results of fixed field intensity-modulated radiation therapy (FF-IMRT) plans for linac equipped with dual-layered MLC. Methods and materials: A total of 213 FF-IMRT treatment plans, including 1383 beams from various treatment sites, were selected and delivered with portal dosimetry verification on Halcyon linac. Gamma analysis was performed using 1%/1, 2%/2, and 3%/2 mm criteria with a 10% threshold. The training set (TS) of ML models consisted of 1106 beams, and an independent evaluation set (ES) consisted of 277 beams. For each beam, 33 complexity metrics were extracted as input data for training models. Three ML algorithms (gradient boosting decision tree/GBDT, random forest/RF, and Poisson Lasso/PL) were utilized to build the models and predict gamma passing rates (GPRs). To improve the prediction accuracy in the rare region, a method of reweighting for TS has been performed and compared to the unweighted results. The importance of complexity metrics was studied by permuted interesting features. Results: The GBDT model had the best performance in this study. In ES, the minimal mean prediction error for unweighted results was 1.93%,1.16%,0.78% under 1%/1, 2%/2, and 3%/2 mm criteria, respectively, from GBDT model. Comparing to the unweighted results, the models after reweighting gained up to 30% improvement in the rare region, whereas the overall prediction error was slightly worse depending on the kind of models. For feature importance, 2 tree-based models (GBDT and RF) had in common the top 10 most important metrics as well as the same metric with the largest impact. Conclusion: For linac equipped with novel dual-layered MLC, the ML model based on GBDT algorithm shows a certain degree of accuracy for GPRs prediction. The specific ML model for dual-layered MLC configuration could be a useful tool for physicists detecting PSQA measurement failures. [ABSTRACT FROM AUTHOR]

Alzheimer's disease (AD) is the most common cause of dementia. Previous studies have found disrupted resting state functional connectivities (rsFCs) in various brain networks in the AD patients. However, few studies have focused on the rsFCs of the cerebellum and its sub-regions in the AD patients. In this study, we collected resting-state functional magnetic resonance imaging (rs-fMRI) data including 32 AD patients and 38 healthy controls (HCs). We selected two cognitive-related subregions of the cerebellum as seed region and mapped the whole-brain rsFCs for each subregion. We identified several distinct rsFC patterns of the two cognitive-related cerebellar subregions: default-mode network (DMN), frontoparietal network (FPN), visual network (VN) and sensorimotor network (SMN). Compared with the controls, the AD patients showed disrupted rsFCs in several different networks (DMN, VN and SMN), predicting the impairment of the functional integration in the cerebellum. Notably, these abnormal rsFCs of the two cerebellar subregions were closely associated with cognitive performance. Collectively, we demonstrated the distinct rsFCs patterns of cerebellar sub-regions with various functional networks, which were differentially impaired in the AD patients. [ABSTRACT FROM AUTHOR]

Objectives: Although it is widely observed that chronic insomnia disorder (CID) is associated with cognitive impairment, the neurobiological mechanisms underlying this remain unclear. Prior neuroimaging studies have confirmed that a close correlation exists between functional connectivity and cognitive impairment. Based on this observation, in this study we used resting-state functional magnetic resonance imaging (rs-fMRI) to study the relationship between whole brain functional connectivity and cognitive function in CID. Methods: We included 39 patients with CID and 28 age-, gender-, and education-matched healthy controls (HC). Abnormalities in functional connectivity were identified by comparing the correlation coefficients for each pair of 116 brain regions between CID and HC. Results: Cognitive impairment was associated with reduced subjective insomnia scores after controlling for age, gender, and educational effects. Compared with HC, patients with CID had larger negative correlations within the task-negative network [medial prefrontal cortex (mPFC), precuneus, inferior temporal gyrus, cerebellum, and superior parietal gyrus], and between two intrinsic anti-correlation networks (mPFC and middle temporal gyrus; supplementary motor area and cerebellum). Patients with CID also had decreased positive correlations within the default mode network (DMN), and between the cerebellum and DMN, which mainly comprises the mPFC and posterior cingulated cortex. There were positive correlations of decreased positive connectivity with subjectivesleep scores and MMSE scores, and increased negative correlations between the task-negative-network and MMSE scores in CID. Conclusions: Using rs-fMRI, our results support previous observations of cortical disconnection in CID in the prefrontal and DMN networks. Moreover, abnormal correlations within the task-negative network, and between two intrinsically anti-correlation networks, might be important neurobiological indicators of CID and associated cognitive impairment. [ABSTRACT FROM AUTHOR]

Preeclampsia (PE) is initiated by abnormal placentation in the early stages of pregnancy, followed by systemic activation of endothelial cells of the maternal small arterioles in the late second or third trimester (TM) of pregnancy. During normal pregnancy, placental cytotrophoblasts (CTBs) invade the maternal uterine wall and spiral arteries, whereas this process is interrupted in PE. However, it is not known how the malformed placenta triggers maternal endothelial crisis and the associated manifestations. Here, we have focused on the association of CD81 with PE. CD81, a member of the tetraspanin superfamily, plays significant roles in cell growth, adhesion, and motility. The function of CD81 in human placentation and its association with pregnancy complications are currently unknown. In the present study, we have demonstrated that CD81 was preferentially expressed in normal first TM placentas and progressively downregulated with gestation advance. In patients with early-onset severe PE (sPE), CD81 expression was significantly up-regulated in syncytiotrophoblasts (STBs), CTBs and the cells in the villous core. In addition, high levels of CD81 were observed in the maternal sera of patients with sPE. Overexpressing CD81 in CTBs significantly decreased CTB invasion, and culturing primary human umbilical vein endothelial cells (HUVECs) in the presence of a high dose of exogenous CD81 resulted in interrupted angiogenesis and endothelial cell activation in vitro. Importantly, the phenotype of human PE was mimicked in the CD81-induced rat model. [ABSTRACT FROM AUTHOR]

Abnormal macrophage polarization at the maternal-fetal interface may contribute to the development of Preeclampsia (PE). The reason why macrophage polarization changed in PE is still unclear. Decidual mesenchymal stem cells (dMSCs) could regulate macrophage polarization. However, miRNA in dMSCs of PE were maladjusted. Therefore, we speculated that miRNA may affect dMSC-regulated macrophage polarization. In this study, we found that miR-494-overexpressed dMSCs inhibit M2 macrophage polarization and this inhibitory effect is mediated by miR-494-reduced PGE2 secretion. Furthermore, we proved that miR-494 is induced by TGF-β3. In summary, our findings suggest that the high expression of TGF-b3 in PE decidua stimulates miR-494 in dMSCs and attenuates the regulation of MSC switching the macrophage toward M2 type, contributing to an immune imbalance at maternal-fetal interface. [ABSTRACT FROM AUTHOR]

The amygdala is an important brain area involved in cognitive procession and emotional regulation. Previous studies have typically considered the amygdala as a single structure, which likely masks contribution of individual amygdala subdivisions. Actually, the amygdala is heterogeneous and composed of structurally and functionally distinct nuclei, which may present different connectivity patterns and predict to relevant cognitive deficits in Alzheimer's disease (AD). However, little is known about functional connectivity of amygdala subregions in the resting state in AD subjects. Here, we employed resting-state functional MRI (fMRI) to examine functional connectivity changes of subregions comparing the AD patients with the age-matched control subjects. Thirty-two AD and 38 control subjects were analyzed. We defined three subregions of the amygdala according to probabilistic cytoarchitectonic atlases and mapped the whole-brain resting-state functional connectivity for each subregion: The central medial nucleus (CM) of amygdala exhibited connections with the lentiform nucleus, parahippocampus and lateral temporal gyrus; the lateral basal nucleus (LB) of amygdala functionally connected with the parahippocampus, lateral temporal gyrus, middle occipital gyrus and medial prefrontal cortex; and the superficial nucleus (SF) of amygdala had connection with the parahippocampus, lentiform nucleus, lateral temporal gyrus, insula, middle occipital gyrus, precentral and postcentral gyrus. Comparing with the controls, the AD patients presented disrupted connectivity patterns in the LB of amygdala, which predicted disconnection with the left uncus, right insula, right precentral gyrus, the left superior temporal gyrus and right claustrum. These findings in a large part supported our hypothesis and provided a new insight in understanding the pathophysiological mechanisms of AD. [ABSTRACT FROM AUTHOR]

In recent years, Chinese wind power has progressed rapidly, such that most accessible high quality, onshore sites are either operational or at least in some stage of development. Thus, offshore wind power has become the new industry focus. This paper reviews the development of China's offshore wind power and its current status. All aspects of preliminary planning, design, approval, construction, O&M, and electricity pricing policy are discussed from a developer's perspective. Data and key points are introduced, based on current engineering practices. European developments are reviewed briefly to help assess similar problems and issues in China. This study suggests that China's relative lack of experience must be recognized. Nevertheless, the development of this nascent technology is already underway. [ABSTRACT FROM AUTHOR]

Background Mesenchymal stem cells (MSCs) at maternal-fetal interface are considered to play an important role in the pathogenesis of pre-eclampsia (PE). microRNAs (miRNAs) also have an important influence on differentiation, maturation, and functions of MSCs. Our aim in this study was to determine the differential expression of miRNAs in decidua-derived MSCs (dMSCs) from severe PE and normal pregnancies. Results miRNA expression profiles in dMSCs from five patients with severe PE and five healthy pregnant women were screened using microarray. Then, bioinformatic analysis of the microarray results was performed. Out of 179 differentially expressed miRNAs, 49 miRNAs had significant (p < 0.05) differential expression of ⩾ 2.0-fold changes, including 21 up-regulated and 28 down-regulated. miRNA-Gene-network and miRNA-Gene ontology (GO) - network analyses were performed. Overall, 21 up-regulated and 15 down-regulated miRNAs showed high degrees in these analyses. Moreover, the significantly enriched signaling pathways and GOs were identified. The analyses revealed that pathways associated with cell proliferation, angiogenesis, and immune functions were highly regulated by the differentially expressed miRNAs, including Wnt signaling pathway, mitogen-activated protein kinase signaling pathway, transforming growth factor beta signaling pathway, T-cell receptor signaling pathway, and B cell receptor signaling pathway. Four miRNA predicted target genes, vascular endothelial growth factor A (VEGFA), indoleamine 2,3-dioxygenase, suppression of cytokine signaling 3, and serine/threonine protein phosphatase 2A 55 kDa regulatory subunit B α isoform (PPP2R2A) were all decreased in dMSCs from patients with PE. Furthermore, the physiological roles of miR-16 and miR-136 in the down-regulation of VEGFA and PPP2R2A, respectively, were confirmed through reporter assays. Conclusions These findings suggest that miRNAs in dMSCs may be important regulatory molecules in the development of PE. [ABSTRACT FROM AUTHOR]

We aim to clarify the mechanisms of acupuncture in treating mild cognitive impairment (MCI) and Alzheimer disease (AD) by using functional magnetic resonance imaging (fMRI). Thirty-six right-handed subjects (8 MCI patients, 14 AD patients, and 14 healthy elders) participated in this study. Clinical and neuropsychological examinations were performed on all the subjects. MRI data acquisition was performed on a SIEMENS verio 3-Tesla scanner. The fMRI study used a single block experimental design. We first acquired the baseline resting state data in the initial 3 minutes; we then acquired the fMRI data during the procession of acupuncture stimulation on the acupoints of Tai chong and Hegu for the following 3 minutes. Last, we acquired fMRI data for another 10 minutes after the needle was withdrawn. The preprocessing and data analysis were performed using the statistical parametric mapping (SPM8) software. Then the two-sample t-tests were performed between each two groups of different states. We found that during the resting state, brain activities in AD and MCI patients were different from those of control subjects. During the acupuncture and the second resting state after acupuncture, when comparing to resting state, there are several regions showing increased or decreased activities in MCI, AD subjects compared to normal subjects. Most of the regions were involved in the temporal lobe and the frontal lobe, which were closely related to the memory and cognition. In conclusion, we investigated the effect of acupuncture in AD and MCI patients by combing fMRI and traditional acupuncture. Our fMRI study confirmed that acupuncture at Tai chong (Liv3) and He gu (LI4) can activate certain cognitive-related regions in AD and MCI patients. [ABSTRACT FROM AUTHOR]

The baseline and longitudinal changes of the posterior cingulate cortex (PCC) connectivity were assessed in order to clarify the neural mechanism of mild cognitive impairment (MCI). Twenty-eight right-handed subjects (14 MCI patients and 14 healthy elders) participated in this study. Clinical and neuropsychological examinations were performed on all the subjects. PCC functional connectivity was studied by examining the correlation between low frequency fMRI signal fluctuations in the PCC and those in all the other brain regions. Additionally, we traced all the MCI patients and compared their PCC connectivity in the initial stage and that in 3 years later. We also explored the relationship between the PCC functional connectivity strength and cognitive performances. Our results are as follows: Functional connectivity between the PCC and a set of regions is decreased in MCI patients. Most of these regions are within the default mode network (DMN). Three years later, the regions of superior frontal gyrus (SFG) and middle frontal gyrus (MFG) presented further decreased connectivity to the PCC in MCI. In addition, we also find enhanced functional connectivity between PCC and medial prefrontal cortex (MPFC), PCC and anterior cingulate cortex (ACC) in MCI patients. At last, our research also shows that the PCC connectivity with some regions significantly correlates with the cognitive performances of patients as measured by mini-mental state examination (MMSE), and California verbal learning test (CVLT) scores. The baseline and longitudinal changes of the PCC connectivity in our study suggest that impairment and compensation coexist in the disease progress of MCI patients. [ABSTRACT FROM AUTHOR]

Background: Passively acquired maternal antibodies in infants may inhibit active immune responses to vaccines. Whether maternal antibody against hepatitis B surface antigen (anti-HBs) in infants may influence the long-term immunogenicity of hepatitis B vaccine remains unknown. Methodology/Principal Findings: Totally 338 pairs of mothers and children were enrolled. All infants were routinely vaccinated against hepatitis B based on 0-, 1- and 6-month schedule. We characterized the transplacental transfer of maternal anti-HBs, and compared anti-HBs response in children of mothers with or without anti-HBs. In a prospective observation, all 63 anti-HBs positive mothers transferred anti-HBs to their infants; 84.1% of the infants had higher anti-HBs concentrations than their mothers. One and half years after vaccination with three doses of hepatitis B vaccine, the positive rate and geometric mean concentration (GMC) of anti-HBs in 32 infants with maternal anti-HBs were comparable with those in 32 infants without maternal antibody (90.6% vs 87.5%, P = 0.688, and 74.5 vs 73.5 mIU/ml, P = 0.742, respectively). In a retrospective analysis, five and half years after vaccination with three doses vaccine, the positive rates of anti-HBs in 88 children of mothers with anti-HBs ≥1000 mIU/ml, 94 children of mothers with anti-HBs 10-999 mIU/ml, and 61 children of mothers with anti-HBs <10 mIU/ml were 72.7%, 69.2%, and 63.9% (P = 0.521), respectively; anti-HBs GMC in these three groups were 38.9, 43.9, and 31.7 mIU/ml (P = 0.726), respectively. Conclusions/Significance: The data demonstrate that maternal anti-HBs in infants, even at high concentrations, does not inhibit the long-term immunogenicity of hepatitis B vaccine. Thus, current hepatitis B vaccination schedule for infants will be still effective in the future when most infants are positive for maternal anti-HBs due to the massive vaccination against hepatitis B. [ABSTRACT FROM AUTHOR]

The known regional abnormality of the dorsolateral prefrontal cortex (DLPFC) and its role in various neural circuits in mild cognitive impairment (MCI) has given prominence to its importance in studies on the disconnection associated with MCI. The purpose of the current study was to examine the DLPFC functional connectivity patterns during rest in MCI patients and the impact of regional grey matter (GM) atrophy on the functional results. Structural and functional MRI data were collected from 14 MCI patients and 14 age, gender-matched healthy controls. We found that both the bilateral DLPFC showed reduced functional connectivity with the inferior parietal lobule (IPL), superior/medial frontal gyrus and sub-cortical regions (e.g., thalamus, putamen) in MCI patients when compared with healthy controls. Moreover, the DLPFC connectivity with the IPL and thalamus significantly correlated with the cognitive performance of patients as measured by mini-mental state examination (MMSE), clock drawing test (CDT), and California verbal learning test (CVLT) scores. When taking GM atrophy as covariates, these results were approximately consistent with those without correction, although there may be a decrease in the statistical power. These results suggest that the DLPFC disconnections may be the substrates of cognitive impairments in MCI patients. In addition, we also found enhanced functional connectivity between the left DLPFC and the right prefrontal cortex in MCI patients. This is consistent with previous findings of MCI-related increased activation during cognitive tasks, and may represent a compensatory mechanism in MCI patients. Together, the present study demonstrated the coexistence of functional disconnection and compensation in MCI patients using DLPFC functional connectivity analysis, and thus might provide insights into biological mechanism of the disease. [ABSTRACT FROM AUTHOR]

Background: Magnetic resonance spectroscopy (MRS) plays an important role in early diagnosis of Alzheimer disease (AD). There are many reports on MRS studies among individuals with AD and mild cognitive impairment (MCI). However, very few studies have compared spectroscopic data of different limbic regions among AD and MCI subjects. Purpose: To compare metabolite changes of different regions in the brain of AD and MCI patients by using 3.0T short-echo-time MRS. Material and Methods: Metabolite ratios in the hippocampus and posterior cingulate area were compared in a group of patients with AD (n=16), MCI (n=16), and normal subjects as a control group (n=16). Clinical neuropsychological tests were measured in all subjects. Results: In the hippocampus, there were significant differences in N-acetylaspartate (NAA)/creatine (Cr), myo-inositol (mI)/Cr, and mI/NAA ratios among the three groups. However, there were no significant differences in choline (Cho)/Cr ratio among the three groups. In the posterior cingulate area, there were no significant differences in the NAA/Cr, Cho/Cr, and mI/Cr ratios among the three groups. However, there were significant differences in mI/NAA ratio between patients with AD and the control group, and between the AD and MCI groups. In addition, there was significant correlation between mI/NAA ratio and Mini Mental Status Exam (MMSE) score in subjects with AD and MCI. Conclusion: The study reveals that the elevation of mI/NAA ratio in the hippocampus is more significant than that in the posterior cingulate area, which corresponds to the pathologic procession of AD. The ratios of mI/NAA in the hippocampus and in the posterior cingulate area together provide valuable discrimination among the three groups (AD, MCI, and controls). There is a significant correlation between mI/NAA ratio and cognitive decline. [ABSTRACT FROM AUTHOR]

Purpose: To report 28 cases of infectious keratitis related to orthokeratology lens overnight wear in China. Methods: From March 2000 to August 2001, 28 cases of infectious keratitis related to overnight orthokeratology lens wear were diagnosed in Beijing Institute of Ophthalmology. These were retrospectively reviewed with regard to the pathogens isolated, duration of wear, the time since onset of symptoms, and age. Cultures of corneal scrapes for bacteria, fungus and Acanthamoeba were performed in all of the 28 cases. Results: All cases were students, including 10 males and 18 females, average age was 16 years (range 10–21 years). The duration of orthokeratology overnight wearing was from 2 weeks to 2 years. Uncorrected visual acuity (UCVA) on initial examination in our institute was from 20/200 to light perception. Of 28 isolates, 24 were culture positive (including 11 bacteria, 11 Acanthamoeba and two fungi), and four were culture negative. In two of the four culture negative cases, Acanthamoeba cysts were detected in the corneal stroma with the confocal microscope. Acanthamoeba and Pseudomonas aeruginosa accounted for 75% (21 of 28) of the cases of infectious keratitis. Conclusion: Infectious keratitis is a severe complication associated with overnight orthokeratology lens wear. Ophthalmologists should pay more attention to this complication in practice. [ABSTRACT FROM AUTHOR]

To investigate the microbiology of specimens from patients with chronic dacryocystitis.A total of 100 samples were obtained from the contents of the lacrimal duct in 91 consecutive patients with chronic dacryocystitis, including nine bilateral cases. These samples were cultured for aerobic and anaerobic bacteria and fungi with a routine microbiological technique. Positive cultured isolates were identified.A total of 180 strains were isolated from the 85 bacterial samples, including 150 strains of aerobic bacteria and 30 strains of anaerobic bacteria. Fungi were found in eight samples and actinomyces in three samples. The bacterial species that were most frequently found wereStaphylococcusspecies, representing 34.5% of all strains, followed byCorynebacterium diphtheroides(15.5%). The sensitivity tests revealed that levo-ofloxacin and amikacin were the most effective antibiotics.Gram positive cocci was the predominant pathogen of chronic dacryocystitis. Levo-ofloxacin and amikacin had the best effectin vitro. [ABSTRACT FROM AUTHOR]