Study and analysis of the correlation between lumbar spondylolisthesis and Modic changes.

Background: This study aimed to explore the risk factors of Modic changes in lumbar spondylolisthesis. Methods: The distribution of Modic changes in different types of lumbar spondylolisthesis, degree of spondylolisthesis, and degree of intervertebral disc degeneration in patients with lumbar spondylolisthesis was observed and analyzed. Statistical analysis was conducted to assess whether intervertebral disc degeneration, local mechanical changes, etc. affect the occurrence of Modic changes. The risk factors of Modic changes in lumbar spondylolisthesis were further illustrated. Results: The age in the lumbar spondylolisthesis with Modic changes group was younger than that in the lumbar spondylolisthesis without Modic changes group, and the bone mineral density was better in the lumbar spondylolisthesis with Modic changes group than that in the lumbar spondylolisthesis without Modic changes group, P < 0.05. The two groups statistically differed in intervertebral disc height (IDH) and disc angle on magnetic resonance imaging (MRI). In the classification of Modic changes, the incidence of type II was the highest. The incidence of Modic changes is higher in isthmic spondylolisthesis than in degenerative spondylolisthesis. With the aggravation of lumbar spondylolisthesis and intervertebral disc degeneration, the incidence of Modic changes gradually increased. Modic changes are most commonly seen in both the upper and lower endplates. Logistic regression analysis showed that the occurrence of Modic changes in lumbar spondylolisthesis was significantly correlated with IDH, disc angle on MRI, type of spondylolisthesis, degree of spondylolisthesis, and degree of intervertebral disc degeneration, P < 0.05. Conclusions: The occurrence of Modic changes is related to the type of spondylolisthesis, the degree of spondylolisthesis, the degree of disc degeneration, the decrease of intervertebral disc height, and local stress angulation.

Systematic review and meta-analysis of the efficacy and safety of adjunctive use of tirofiban in patients treated with endovascular therapy for acute ischemic stroke at different embolic sites.

BACKGROUND: The use of tirofiban as an adjunct to endovascular therapy (EVT) for acute ischemic stroke has been controversial. We aimed to assess the differences in safety and efficacy of EVT adjuvant to tirofiban in patients with anterior circulation stroke (ACS) and posterior circulation stroke (PCS). METHODS: We systematically searched Pubmed, Embase, Cochrane Library, and Web of Science. Cohort studies and randomized controlled trials that compared treatment with tirofiban combined with EVT and EVT alone were included in our meta-analysis. The safety outcomes were symptomatic intracranial hemorrhage, and 3-month mortality. The efficacy outcomes were good functional outcome, excellent functional outcome, and successful recanalization (mTICI ≥ 2b). We performed subgroup analyses of anterior and posterior circulation strokes. RESULTS: We included 15 studies with 4608 patients. For safety outcomes, tirofiban significantly reduced 3-month mortality in the ACS subgroup (odd ratio [OR] = 0.80, 95% confidence interval [CI] = 0.65-0.98, P = .03) without increasing the rate of symptomatic intracranial hemorrhage (OR = 1.12, 95% CI = 0.88-1.44, P = .35). In the PCS subgroup, tirofiban significantly reduced 3-month mortality (OR = 0.63, 95% CI = 0.50-0.80, P = .0001) and symptomatic intracranial hemorrhage (OR = 0.60, 95% CI = 0.37-0.95, P = .03). For efficacy outcomes, in the ACS subgroup, tirofiban significantly improved good functional outcome (OR = 1.24, 95% CI = 1.06-1.45, P = .008) but did not improve recanalization (OR = 1.17, 95% CI = 0.93-1.47, P = .17) and excellent functional outcome (OR = 1.19, 95% CI = 0.97-1.46, P = .10). In the PCS subgroup, tirofiban significantly improved recanalization rate (OR = 1.94, 95% CI = 1.43-2.65, P < .0001) and did not improve good functional outcome (OR = 1.03, 95% CI = 0.81-1.30, P = .81) and excellent functional outcome (OR = 0.84, 95% CI = 0.58-1.20, P = .34). CONCLUSION: In acute ischemic stroke patients undergoing EVT, tirofiban improves good functional outcomes in ACS patients and increases recanalization rates in PCS patients on the 1 hand, reduces mortality, and does not increase the risk of symptomatic intracranial hemorrhage on the other. Tirofiban is safe and effective in both anterior circulation stroke and posterior circulation stroke patients undergoing EVT. More large multicentre randomized controlled studies are needed in the future.

Meta-analysis of the efficacy and safety of tirofiban in patients with acute ischaemic stroke undergoing mechanical thrombectomy.

INTRODUCTION: Mechanical thrombectomy is now widely used in acute ischaemic stroke, but its adjunctive antiplatelet aggregation regimen is controversial. This study aimed to investigate the safety and efficacy of tirofiban in patients with acute ischaemic stroke (AIS) who underwent mechanical thrombectomy. METHODS: We systematically searched Pubmed, Embase, Cochrane Library, and Web of science. Randomized controlled studies and cohort studies comparing the tirofiban group and non-tirofiban group (control group) in patients with AIS who underwent mechanical thrombectomy. The primary safety outcomes were symptomatic intracranial hemorrhage (sICH), 3-month mortality, and re-occlusion rate. The primary efficacy outcomes were good functional outcome (mRS 0-2), excellent functional outcome (mRS 0-1), and successful recanalization (mTICI≥2b). RESULTS: We included 22 studies with a total of 6062 patients. For safety outcomes, the tirofiban group had a non-significantly higher rate of sICH (OR = 0.90, 95 % CI = 0.73-1.10, P = 0.29) and a significantly lower rate of re-occlusion (OR = 0.40, 95 % CI = 0.19-0.82, P = 0.01) and 3-month mortality (OR = 0.71, 95 % CI = 0.61-0.82, P < 0.00001) compared to the control group. In terms of efficacy outcomes, significant improvement in good functional outcomes (mRS 0-2) (OR = 1.24, 95 % CI = 1.11-1.39, P = 0.0002) and recanalization rate (OR = 1.38, 95% CI = 1.17-1.62, P = 0.0001) compared to tirofiban, but not significant improvement in excellent functional outcomes(OR = 1.14, 95 % CI = 0.93-1.39, P = 0.21). In addition, compared with cardiogenic stroke, the large atherosclerotic stroke had a higher rate of good functional outcome (OR = 1.58, 95 % CI = 1.18-2.11, P = 0.002) and a lower rate of 3-month mortality (OR = 0.58, 95 % CI = 0.39-0.85, P = 0.005). Subgroup analysis by route of administration showed a significant improvement in good functional outcome in the intravenous group (OR = 1.27, 95 % CI = 1.08-1.50, P = 0.004), while no significant difference was found between the arterial and arteriovenous groups. CONCLUSION: Treatment with tirofiban in patients with AIS with mechanical thrombectomy is effective in improving functional prognosis, arterial recanalization rates, and reducing 3-month mortality and re-occlusion rates, particularly in patients with large atherosclerotic stroke, without increasing the rate of symptomatic intracranial hemorrhage. Intravenous administration of tirofiban significantly improves the clinical prognosis compared to arterial administration. Tirofiban is effective and safe in patients with AIS.

Risk factors for recurrence of gestational diabetes mellitus in southern Chinese women: a retrospective study.

OBJECTIVES: Predictors of gestational diabetes mellitus (GDM) recurrence (GDMR) was determined in southern Chinese women. MATERIAL AND METHODS: A total of 376 women with GDM who had two consecutive singleton deliveries at our hospital between January 2014 and October 2020 were enrolled in the current study. We retrospectively compared the clinical characteristics, fasting plasma glucose level (FPG-1), and oral glucose tolerance test-1h-1 and -2h-1 (OGTT 1hr-1: 1-h post-load glucose level during the first pregnancy and OGTT 2hr-1: 2-h post-load glucose level during the first pregnancy) for the first pregnancy between patients in the GDMR group (n = 166) and the non-GDMR group (n = 210). RESULTS: The incidence of GDMR in the study population was 44.15%. During the first pregnancy, women in the GDMR group had significantly higher OGTT 1h-1, OGTT 2h-1, and FPG-1 + OGTT 1h + 2h-1 compared to the non-GDMR group. When the threshold of the FPG-1 + OGTT 1h + 2h-1 level in the first pregnancy was > 23.6 mmol/L, the specificity for predicting GDMR was 0.85, the sensitivity was 0.45, and the area under the receiver operating characteristic curve (ROC-AUC) was 0.70, indicating a 70% probability of predicting GDMR in the next pregnancy. Logistic regression analysis showed that patients with a combined abnormal FPG-1 + OGTT 1h + 2 h-1 level had a 10-fold increased risk for GDMR in subsequent pregnancies than patients with normal indicators (OR: 10.542, 95% CI: 3.097-35.881; p < 0.0001). CONCLUSIONS: The OGTT 1h-1 and OGTT 2h-1 are independent risk factors for GDMR in southern Chinese women. Women with an FPG-1 + OGTT 1h + 2h-1 threshold level > 23.6 mmol/L in the first pregnancy had a 10-fold greater probability of developing GDMR in the second pregnancy than women in the non-GDMR group.

An efficient process for aromatic VOCs degradation: Combination of VUV photolysis and photocatalytic oxidation in a wet scrubber.

The elimination of volatile organic compounds (VOCs) via vacuum ultraviolet (VUV) photolysis is greatly limited by low removal efficiency and gaseous byproducts generation, while photocatalytic oxidation of VOCs suffers from catalytic deactivation. Herein, a coupled process of gaseous VUV photolysis with aqueous photocatalytic oxidation with P25 as the catalyst was firstly proposed for efficient aromatic VOCs removal (VUV/P25). The removal efficiency of toluene reached 86.2% in VUV/P25 process, but was only 33.6% and 58.1% in alone gaseous VUV photolysis and aqueous ultraviolet photocatalytic oxidation (UV/P25) process, respectively. Correspondingly, the outlet CO2 concentration in VUV/P25 process reached 132 ppmv. Toluene was firstly destructed by high-energy photons generated from gaseous VUV photolysis, resulting in its incomplete oxidation to form soluble intermediates including acids, aldehydes, esters. These soluble intermediates would be further degraded and mineralized into CO2 in subsequent aqueous UV/P25 process. Notably, the concentrations of intermediates in VUV/P25 were much lower than those in VUV photolysis, indicating the synergy effect of VUV photolysis and UV/P25 process. The stability tests proved that VUV/P25 process maintained an excellent toluene degradation performance and P25 did not suffer from catalytic deactivation. In addition to toluene, the VUV/P25 system also achieved the efficient and sustainable degradation of styrene and chlorobenzene, suggesting its good application prospect in industrial VOCs treatment. This study proposes an efficient and promising strategy for deep oxidation of multiple aromatic VOCs in industries.

Comparative analysis of the effects of OLIF and TLIF on adjacent segments after treatment of L4 degenerative lumbar spondylolisthesis.

BACKGROUND: The fusion of the lumbar spine may lead to the degeneration of the adjacent segments. In this study, the effects of OLIF and TLIF on adjacent segments after treatment of L4 degenerative lumbar spondylolisthesis (DLS) were compared and analysed. METHODS: This was a retrospective analysis of the medical records of consecutive patients treated with OLIF or TLIF for L4DLS. They were divided into the OLIF group and TLIF group based on different treatment methods. Cage height, segmental lordosis (SL), lumbar lordosis (LL), pelvic incidence (PI), pelvic tilt (PT), and sacral slope (SS) were compared between the two groups, and the postoperative biomechanical changes were analysed by establishing the disc angle (DA). The clinical outcomes were analysed by comparing the visual analogue scale (VAS), Oswestry Disability Index (ODI) and incidence of adjacent segment disease (ASDis) between the two groups. The intervertebral disc height (IDH), intervertebral foramen height (IDH), intervertebral foramen area (IFA), sliding distance (SD), and angular displacement (AD) in L3-4 and L5-S1 were compared between the two groups. The incidence of aggravated disc degeneration (ADD), the incidence of aggravated zygapophyseal joint degeneration (AJD) and the incidence of adjacent segment degeneration (ASDeg) were compared between the two groups for radiological degeneration. RESULTS: At the last follow-up, there was one case of ASDis in the OLIF group (2.78%) and two cases in the TLIF group (5.56%). At the last follow-up, compared with the preoperative values, IDH, IFH, and IFA of the adjacent segments above and below L4-5 decreased in both groups (P < 0.05); the SD and AD increased in both groups (P < 0.05). The cage height and L4-5 IDH in the OLIF group were significantly higher than those in the TLIF group (P < 0.05). SL, LL, PT, SS, and L5- S1DA were significantly improved in the OLIF group compared with the TLIF group (P < 0.05). The incidence of L3-4ASDeg in the two groups was higher than that of L5-S1. The incidence of ASDeg and the incidence of L5-S1ADD in the OLIF group were lower than those in the TLIF group, but the incidence of L5-S1AJD was higher than that in the TLIF group. CONCLUSION: L4DLS after OLIF and TLIF treatment will cause adjacent segment degeneration, and L3-4 degeneration is more obvious than L5-S1 degeneration. OLIF has more advantages in restoring lumbar sagittal balance. Compared with TLIF, OLIF can weaken the degeneration of the L5-S1 disc and increase the degeneration of the L5-S1 zygapophyseal joints.

Verte-Box: A Novel Convolutional Neural Network for Fully Automatic Segmentation of Vertebrae in CT Image.

Due to the complex shape of the vertebrae and the background containing a lot of interference information, it is difficult to accurately segment the vertebrae from the computed tomography (CT) volume by manual segmentation. This paper proposes a convolutional neural network for vertebrae segmentation, named Verte-Box. Firstly, in order to enhance feature representation and suppress interference information, this paper places a robust attention mechanism on the central processing unit, including a channel attention module and a dual attention module. The channel attention module is used to explore and emphasize the interdependence between channel graphs of low-level features. The dual attention module is used to enhance features along the location and channel dimensions. Secondly, we design a multi-scale convolution block to the network, which can make full use of different combinations of receptive field sizes and significantly improve the network's perception of the shape and size of the vertebrae. In addition, we connect the rough segmentation prediction maps generated by each feature in the feature box to generate the final fine prediction result. Therefore, the deep supervision network can effectively capture vertebrae information. We evaluated our method on the publicly available dataset of the CSI 2014 Vertebral Segmentation Challenge and achieved a mean Dice similarity coefficient of 92.18 ± 0.45%, an intersection over union of 87.29 ± 0.58%, and a 95% Hausdorff distance of 7.7107 ± 0.5958, outperforming other algorithms.

Fast Segmentation of Vertebrae CT Image Based on the SNIC Algorithm.

Automatic image segmentation plays an important role in the fields of medical image processing so that these fields constantly put forward higher requirements for the accuracy and speed of segmentation. In order to improve the speed and performance of the segmentation algorithm of medical images, we propose a medical image segmentation algorithm based on simple non-iterative clustering (SNIC). Firstly, obtain the feature map of the image by extracting the texture information of it with feature extraction algorithm; Secondly, reduce the image to a quarter of the original image size by downscaling; Then, the SNIC super-pixel algorithm with texture information and adaptive parameters which used to segment the downscaling image to obtain the superpixel mark map; Finally, restore the superpixel labeled image to the original size through the idea of the nearest neighbor algorithm. Experimental results show that the algorithm uses an improved superpixel segmentation method on downscaling images, which can increase the segmentation speed when segmenting medical images, while ensuring excellent segmentation accuracy.

Perspectives of ERCC1 in early-stage and advanced cervical cancer: From experiments to clinical applications.

Cervical cancer is a public health problem of extensive clinical importance. Excision repair cross-complementation group 1 (ERCC1) was found to be a promising biomarker of cervical cancer over the years. At present, there is no relevant review article that summarizes such evidence. In this review, nineteen eligible studies were included for evaluation and data extraction. Based on the data from clinical and experimental studies, ERCC1 plays a key role in the progression of carcinoma of the uterine cervix and the therapeutic response of chemoradiotherapy. The majority of the included studies (13/19, 68%) suggested that ERCC1 played a pro-oncogenic role in both early-stage and advanced cervical cancer. High expression of ERCC1 was found to be associated with the poor survival rates of the patients. ERCC1 polymorphism analyses demonstrated that ERCC1 might be a useful tool for predicting the risk of cervical cancer and the treatment-related toxicities. Experimental studies indicated that the biological effects exerted by ERCC1 in cervical cancer might be mediated by its associated genes and affected signaling pathways (i.e., XPF, TUBB3, and. To move towards clinical applications by targeting ERCC1 in cervical cancer, more clinical, in-vitro, and in-vivo investigations are still warranted in the future.

Is There an Association Between Contraception and Sexual Dysfunction in Women? A Systematic Review and Meta-analysis Based on Female Sexual Function Index.

BACKGROUND: A growing body of research investigates the sexual functioning status in women with contraceptives use; however, the evidence is still inconclusive. AIM: To examine whether contraceptives use is associated with a higher risk of female sexual dysfunction (FSD). METHODS: The electronic databases MEDLINE, Embase, Cochrane Library databases, and PsychINFO were systematically screened for eligible studies before December 2019. We only included those studies assessing women's sexual functioning by the Female Sexual Function Index (FSFI). This study was registered on the PROSPERO (ID: CRD42020167723, http://www.crd.york.ac.uk/PROSPERO). OUTCOMES: The strength of the association between contraceptives use and risk of FSD was presented by calculating the standard mean dierences (SMDs) and the relative risk (RR) with a 95% confidence interval (CI). The pooled results were calculated using a random-effects model. RESULTS: A total of 12 studies (7 cross-sectional studies, 3 cohorts, and 1 case-control study) involving 9,427 participants were included. The mean age in the contraceptive users ranged from 22.5 ± 2.4 years to 38.2 ± 4.6 years, while the mean age in the nonusers was 22.5 ± 2.4 years to 36.0 ± 1.0 years. Pooled results showed that no significant difference in the total FSFI scores was observed between contraceptives use and noncontraception (SMD = -1.03, 95% CI: -2.08 to 0.01, P = .053; heterogeneity: I2 = 98.2%, P < .001). In line with this finding, the pooled RR also yielded no association between contraception use and the risk of FSD (RR = 1.29, 95% CI: 0.72-2.28, P = .392; heterogeneity: I2 = 76.0%, P = .0015). However, the subscale sexual desire showed a significant reduction in women who received contraceptives than those did not use contraception (SMD = -1.17, 95% CI: -2.09 to -0.24, P = .014; heterogeneity: I2 = 97.7%, P < .001), while no significant differences were found in sexual arousal, lubrication, orgasm, satisfaction, and pain domain. CLINICAL IMPLICATIONS: Though evidence from this meta-analysis did not support an association between contraceptives use and the risk of FSD, the sexual desire could be significantly impaired by contraceptives use. STRENGTHS & LIMITATIONS: This is the first meta-analysis quantifying the relationship between contraceptives use and the risks of FSD. However, substantial heterogeneities were presented across the included studies. CONCLUSION: No direct association between contraceptives use and the risk of FSD was found. Nevertheless, declining sexual desire was significantly associated with contraceptives use. Additional double-blind, randomized, placebo-controlled trials are still warranted. Huang M, Li G, Liu J, et al. Is There an Association Between Contraception and Sexual Dysfunction in Women? A Systematic Review and Meta-analysis Based on Female Sexual Function Index. J Sex Med 2020;17:1942-1955.

Transcriptomic profiling of purple broccoli reveals light-induced anthocyanin biosynthetic signaling and structural genes.

Purple Broccoli (Brassica oleracea L. var italica) attracts growing attention as a functional food. Its purple coloration is due to high anthocyanin amounts. Light represents a critical parameter affecting anthocyanins biosynthesis. In this study, 'Purple Broccoli', a light-responding pigmentation cultivar, was assessed for exploring the mechanism underlying light-induced anthocyanin biosynthesis by RNA-Seq. Cyanidin, delphinidin and malvidin derivatives were detected in broccoli head samples. Shading assays and RNA-seq analysis identified the flower head as more critical organ compared with leaves. Anthocyanin levels were assessed at 0, 7 and 11 days, respectively, with further valuation by RNA-seq under head-shading and light conditions. RNA sequences were de novo assembled into 50,329 unigenes, of which 38,701 were annotated against four public protein databases. Cluster analysis demonstrated that anthocyanin/phenylpropanoid biosynthesis, photosynthesis, and flavonoid biosynthesis in cluster 8 were the main metabolic pathways regulated by light and had showed associations with flower head growth. A total of 2,400 unigenes showed differential expression between the light and head-shading groups in cluster 8, including 650 co-expressed, 373 specifically expressed under shading conditions and 1,377 specifically expressed under normal light. Digital gene expression (DGE) analysis demonstrated that light perception and the signal transducers CRY3 and HY5 may control anthocyanin accumulation. Following shading, 15 structural genes involved in anthocyanin biosynthesis were downregulated, including PAL, C4H, 4CL, CHS, CHI, F3H and DFR. Moreover, six BoMYB genes (BoMYB6-1, BoMYB6-2, BoMYB6-3, BoMYB6-4, BoMYBL2-1 and BoMYBL2-2) and three BobHLH genes (BoTT8_5-1, BoTT8_5-2 and BoEGL5-3) were critical transcription factors controlling anthocyanin accumulation under light conditions. Based on these data, a light-associated anthocyanin biosynthesis pathway in Broccoli was proposed. This information could help improve broccoli properties, providing novel insights into the molecular mechanisms underpinning light-associated anthocyanin production in purple vegetables.

TargetM6A: Identifying N6-Methyladenosine Sites From RNA Sequences via Position-Specific Nucleotide Propensities and a Support Vector Machine.

As one of the most ubiquitous post-transcriptional modifications of RNA, N6-methyladenosine ( [Formula: see text]) plays an essential role in many vital biological processes. The identification of [Formula: see text] sites in RNAs is significantly important for both basic biomedical research and practical drug development. In this study, we designed a computational-based method, called TargetM6A, to rapidly and accurately target [Formula: see text] sites solely from the primary RNA sequences. Two new features, i.e., position-specific nucleotide/dinucleotide propensities (PSNP/PSDP), are introduced and combined with the traditional nucleotide composition (NC) feature to formulate RNA sequences. The extracted features are further optimized to obtain a much more compact and discriminative feature subset by applying an incremental feature selection (IFS) procedure. Based on the optimized feature subset, we trained TargetM6A on the training dataset with a support vector machine (SVM) as the prediction engine. We compared the proposed TargetM6A method with existing methods for predicting [Formula: see text] sites by performing stringent jackknife tests and independent validation tests on benchmark datasets. The experimental results show that the proposed TargetM6A method outperformed the existing methods for predicting [Formula: see text] sites and remarkably improved the prediction performances, with MCC = 0.526 and AUC = 0.818. We also provided a user-friendly web server for TargetM6A, which is publicly accessible for academic use at http://csbio.njust.edu.cn/bioinf/TargetM6A.

[Surgical treatment of lumbar spondylolisthesis by transforaminal lumbar interbody fusion].

OBJECTIVE: To explore the clinical outcomes of transforminal lumbar interbody fusion (TLIF) technique in treatment of lumbar spondylolisthesis. METHODS: From June 2009 to June 2006, 42 patients underwent TLIF. There were 18 males and 24 females with an average age of 48 (30-68) years. The preoperative diagnoses included lumber degenerative spondylolisthesis (n = 16) and lumbar isthmic spondylolisthesis (n = 26). According to the Meyerding standard, 28 cases were classified as degreeI, 12 as degree II and 2 as degree III. Posterolateral fixation with pedicle screw and decompression, interbody fusion through TLIF technical plus cage for distraction reduction were employed. The evaluation standards of visual analog scale (VAS) and Oswestry disability index (ODI) were applied to evaluate the therapeutic outcomes.Intervertebral height and bone fusion were observed by radiology. RESULTS: All patients underwent surgery safely without any severe complication. The average follow-up period was 19.4 (9-36) months. Compared with preoperative parameters (7.07 ± 0.92), the postoperative scores of VAS decreased significantly (2.52 ± 1.37) and at the final follow-up (2.26 ± 1.61) (P < 0.05); compared with preoperative parameters (68.43 ± 12.81), the postoperative scores of ODI decreased significantly (24.19 ± 11.44) and at the final follow-up (20.86 ± 9.97) (P < 0.05) and no significant difference in VAS or ODI score existed between post-operation and last follow-up (P > 0.05). Compared with preoperative parameters (8.25 ± 1.27), the postoperative height of intervertebral space increased significantly (9.68 ± 1.62) and at the final follow-up (9.33 ± 1.25) (P < 0.05). And intervertebral height decreased at the final follow-up. There was significant difference between post-operation and last follow-up (P = 0.001). At the follow-up of 6.5 months postoperatively, all operated segments achieved fusion standard and no broken screw. There was 1 case of cage dislocation. CONCLUSION: TLIF may be performed easily and safely with fewer complications. And its efficacies are satisfactory for patients with lumbar spondylolisthesis.

Synthesis and characterization of novel polar-embedded silica stationary phases for use in reversed-phase high-performance liquid chromatography.

We have developed a series of new C(10) dipeptide stationary phases via a simple and effective synthetic method. The preparation of the new phases involves the synthesis of silanes and the surface modification of silica. Chromatographic evaluations of these columns were performed using the Engelhardt, Tanaka, and Neue test mixtures. The applicability of these new stationary phases was also evaluated using a series of diagnostic probes including acids, bases or neutral compounds and several generic applications. These new C(10) dipeptide stationary phases showed excellent hydrolytic stability over a wide pH range. Like other existing amide-embedded columns, these new stationary phases exhibit higher retention for polar and hydrophilic compounds and different selectivity as compared to conventional C(18) columns. These new phases are compatible with 100% aqueous mobile phases, and also provide high column efficiency and good peak shapes for both acidic and basic compounds.

[Transforaminal lumbar interbody fusion in the treatment of lumbar intervertebral disc herniation with lumbar instability].

OBJECTIVE: To explore the surgical efficacy of transforaminal lumbar interbody fusion (TLIF) technique in the treatment of lumbar intervertebral disc herniation with lumbar instability. METHODS: From November 2008 to August 2011, 47 patients of lumbar intervertebral disc herniation underwent TLIF. There were 25 males and 22 females with an average age of 52 years (range: 30 - 68). The preoperative diagnoses included lumber intervertebral disc herniation plus lumbar instability (n = 16); lumbar degenerative spondylolisthesis (n = 9); lumbar spinal stenosis (n = 15) and degenerative lumbar scoliosis (n = 7). A total of 63 levels were fused, including single level (n = 31) and double levels (n = 16). Posterolateral fixation was secured with pedicle screw. Unilateral resections of inferior articular facet of superior vertebra and superior articular facet of inferior vertebra were performed to expose unilateral intervertebral vertebral foramen. Decompression of vertebral canal was expanded to the opposite side if symptoms recurred when never root was decompressed satisfactorily. Finally TLIF was performed routinely. The standard criteria of JOA (Japanese Orthopedic Association) and ODI (Oswestry disability index) were applied for efficacy evaluations. And the intervertebral height and bone fusion were observed radiologically. RESULTS: All patients underwent surgery smoothly without severe complications. The average follow-up period was 19.6 months (range: 6 - 36). Significant differences existed in JOA score between pre-operation (11.0 ± 2.8) and postoperation (15.4 ± 3.4) (P = 0.01) and ODI score between pre-operation (37.8 ± 4.6) and postoperation (18.8 ± 3.8). At 6.5 months postoperatively, all operated segments achieved fusion and there was no broken screw. There was 1 case of cage dislocation. CONCLUSION: In select patients of lumbar intervertebral disc herniation with spinal instability, TLIF may be performed easily and safely with fewer complications and total root decompression.

Distribution of the intermediate hosts of Echinococcus multilocularis in Shiqu County, Sichuan, China.

BACKGROUND: The rodentia and lagomorpha animals are the intermediate hosts of Echinococcus multilocularis, their distribution and infection of this parasite may facilitate the infection of definitive hosts such as dogs. The aim of this study was to determine the distribution of the intermediate hosts of Echinococcus multilocularis in Shiqu County, Sichuan, China. METHODS: A systematic sampling method was used to investigate the density of burrows of rodents and lagomorphs at 97 pasture sites in winter and summer pastureland and remote sensing (RS) technology was used to correlate their densities to the distribution of these animals in different landscape types. RESULTS: Based on the densities of Ochotona curzoniae, Microtus fuscus (dependent variable) and their burrow densities (independent variable) in survey points, regression equations were fitted respectively (Ochotona curzoniae, P < 0.0001, R(2) = 0.8705; Microtus fuscus, P < 0.0001, R(2) = 0.9736). Their burrow density in summer pastureland was higher than in winter pastureland (F = 36.65, P < 0.0001). The burrow densities of Ochotona curzoniae and Microtus fuscus in bareland and half-bareland are higher than in grassland (F = 7.73, P < 0.001). CONCLUSIONS: The regression relationship between the densities of Ochotona curzoniae and Microtus fuscus and their burrow densities indicate that the burrow densities could reflect the animal densities and that the burrow density was greater in summer pastureland than in winter pastureland. The main distribution areas of the intermediate hosts were in bareland and half-bareland.

[Recent applications of solid-phase extraction techniques for analysis of trace residues and contaminants in food].

The determination of trace residues and contaminants in food often requires extensive sample extraction and preparation prior to instrumental analysis. Due to the multiplicity and complexity of food matrices, it is not possible to use only one sample preparation technique. This review introduces the application of some new techniques of solid-phase extraction (SPE) in recent years, such as solid-phase microextraction (SPME), stir-bar sorptive extraction (SBSE), matrix solid-phase dispersion (MSPD), molecularly imprinted solid-phase extraction (MISPE) , immunoaffinity-based solid-phase extraction (IASPE), monolithic solid-phase extraction, carbon nanotube solid-phase extraction, in the analysis of trace residues and contaminants in food. At last, future developments in this field are outlined.

[Fleas notified on Microtus fuscus foci in Sichuan province].

OBJECTIVE: To analyzed the variant information on the indices regarding fleas from natural foci of Microtus plague in Sichuan epidemic area during 2000 to 2008. METHODS: Statistical and analytical methods were used on the surveillance data regarding Microtus fuscus plague. RESULTS: There were 19 flea species identified and the share of Callopsylla sparsity was 62.79 percent while the share of Amphipsylla tuta was 30.90 percent on Microtus fuscus plague. The infection rate of fleas and the flea index were the highest in October and the lowest in December and March. Species as Callopsylla sparsity, Amphipsylla tuta and Rhadinopsylla dahurica vicina could naturally infect the Yersinia pestis. CONCLUSION: Microtus fuscus plague could become epidemic when animals and flea species were infected. We should emphasis on plague monitoring program so as to prevent the occurrence of the disease.

Application of nonlinear dynamics analysis in assessing unconsciousness: a preliminary study.

OBJECTIVES: To quantify the degree of unconsciousness with EEG nonlinear analysis and investigate the change of EEG nonlinear properties under different conditions. METHODS: Twenty-one subjects in persistent vegetative state (PVS), 16 in minimally conscious state (MCS) and 30 normal conscious subjects (control group) with brain trauma or stroke were involved in the study. EEG was recorded under three conditions: eyes closed, auditory stimuli and painful stimuli. EEG nonlinear indices such as Lempel-Ziv complexity (LZC), approximate entropy (ApEn) and cross-approximate entropy (cross-ApEn) were calculated for all the subjects. RESULTS: The PVS subjects had the lowest nonlinear indices followed by the MCS subjects and the control group had the highest. The PVS and MCS group had poorer response to auditory and painful stimuli than the control group. Under painful stimuli, nonlinear indices of subjects who recovered (REC) increased more significantly than non-REC subjects. CONCLUSIONS: With EEG nonlinear analysis, the degree of suppression for PVS and MCS could be quantified. The changes of brain function for unconscious subjects could be captured by EEG nonlinear analysis. SIGNIFICANCE: EEG nonlinear analysis could characterise the changes of brain function for unconscious state and might have some value in predicting prognosis of unconscious subjects.

Rehabilitation of patients with chronic normal-pressure hydrocephalus after aneurysmal subarachnoid hemorrhage benefits from ventriculoperitoneal shunt.

UNLABELLED: This study compares the effect and rehabilitation prognosis of 6-month combined ventriculoperitoneal shunt (VPS) versus rehabilitation training alone in chronic normal-pressure hydrocephalus patients. METHOD: After suffering from aneurysmal subarachnoid hemorrhage, 39 subjects were diagnosed with chronic normal-pressure hydrocephalus because of clinical deterioration or nonimprovement of gait ataxia, cognitive disturbance, and/or urinary incontinence during rehabilitation. Twenty-four subjects underwent ventriculoperitoneal shunt (VPS) placement, while 15 subjects did not undergo the procedure. RESULTS: Statistically significant increases in the Barthel Index (BI) were observed between the treatment and control groups 1 month (p < .05) and 6 months (p < .01) after VPS placement. Similar changes also were observed for the Mini-Mental State Examination (MMSE) at the 1-month (p < .01) and 6-month follow-up visits (p < .01). Significant differences in the change in MMSE and BI at admission, before VPS placement, and at 1 month and 6 months after VPS placement in the treatment group were demonstrated (p < .01). CONCLUSION: Chronic normal-pressure hydrocephalus after aneurysmal subarachnoid hemorrhage is an important issue to which clinicians should pay attention. It negatively influences the functional and behavioral outcome of rehabilitation but can be treated.