[Mid-term efficacy of sacral nerve stimulation for the treatment of chronic constipation].

Objective: To investigate the mid-term efficacy of sacral nerve stimulation (SNS) for chronic constipation. Methods: A descriptive case series study was conducted. Patients with chronic constipation were treated in Xijing Hospital of Digestive Disease from February 2013 to December 2018 were retrospectively enrolled. The types of constipation were confirmed based on colon slow transit test, anorectal manometry and defecography in Xi'an Mayinglong Coloproctological Hospital. This study has been registered in China clinical trial registry (Registration No.: ChiCTR-ROC-16008945). Case inclusion criteria: (1) constipation was diagnosed according to Rome III criteria; (2) traditional treatment, including education, diet adjustment, laxative, biofeedback treatment, failed for at least 1 year; (3) there were no constipation-related organic diseases. After excluding neurogenic diseases, including spinal cord injury and multiple sclerosis, 21 patients were included in this study. There were 10 males and 11 females, with an average age of 50.9 (14-76) years. After the relevant examination and evaluation of patients, they underwent percutaneous nerve evaluation (PNE). If patient experienced a good response to PNE after 2 or 3 weeks (≥50%), permanent SNS implantation was performed. The improvement of clinical symptoms and quality of life between the baseline, PNE, and latest follow-up time points were compared. Improvement of clinical symptoms, including autonomic stool frequency per week, autonomic stool days per week, defecation time, visual analogue scale (VAS, lower score indicates more serious symptoms) score and Cleveland clinic constipation score (CCCS, higher score indacates more serious symptoms) criteria. The change of quality of life was scored by SF-36 questionnaires (the higher score indicates better quality of life). Results: Of 21 patients, 18 (85.7%) experienced significant improvement in symptoms with PNE, and 2 patients discontinued treatment due to their dissatisfaction. Sixteen patients (76.2%) received permanent SNS implantation, two of whom underwent bilateral PNE implantation. These patients were followed-up for mean 56 (34-72) months. The treatment was continuously effective in 13 patients (61.9%), including 3 of ODS, 1 of STC and 9 of mixed constipation. Compared with baseline, the score of constipation patients receiving permanent SNS implantation at latest follow-up was shown. The median autonomic stool frequency per week increased from 1.0 (0-7) to 7.5 (0-10) (P<0.001), the median autonomic stool days per week increased from 1.0 (0-7) d to 4.5 (0-7) d (P<0.001), the median defecation time decreased from 19.0 (8-40) minutes to 4.0 (3-31) minutes (P<0.001), the median CCCS decreased from 20.0 (13-30) to 9.0 (6-30) (P<0.001), and the median VAS score increased from 9.0 (7-40) to 80.0 (15-90) (P<0.001). The values of the 8 parts of the SF-36 questionnaire increased (all P<0.05). Conclusion: SNS implantation is safe and has obvious effects on severe constipation with stable mid-term efficacy.

[Functional evaluation after function-preserving gastrectomy].

With the increase of people's health awareness and the progress of medical diagostic technology in recent years, the diagnosis rate of early gastric cancer is increasing year by year. Although radical surgery has good efficacy, how to maximize the preservation of the normal anatomy and function of the stomach and improve the quality of life of patients in the pursuit of radical surgery has become a more important issue in the treatment of early gastric cancer. Under the condition of ensuring radical lymph node dissection, function-preserving gastrectomy can fully preserve gastric function by reducing the resection extent and preserving the pylorus and the vagus nerve, which has advantage of improving quality of life and has great potential in the treatment of early gastric cancer. However, there is no functional evaluation standard for function-preserving gastrectomy at present. Most of the patients are evaluated by quality of life scale, which is relatively subjective. Even though the evaluation of endoscopy, hematology and other objective means can indicate the benefit degree in quality of life brought by functional reconstruction, the evidence level is limited. Therefore, this paper discusses the research status of function-preserving gastrectomy evaluation, postoperative complications, postoperative nutritional status, auxiliary examination and other items in the evaluation of gastric function, and analyzes the prospects of research direction in this field.

Clustering: a neural network approach.

Clustering is a fundamental data analysis method. It is widely used for pattern recognition, feature extraction, vector quantization (VQ), image segmentation, function approximation, and data mining. As an unsupervised classification technique, clustering identifies some inherent structures present in a set of objects based on a similarity measure. Clustering methods can be based on statistical model identification (McLachlan & Basford, 1988) or competitive learning. In this paper, we give a comprehensive overview of competitive learning based clustering methods. Importance is attached to a number of competitive learning based clustering neural networks such as the self-organizing map (SOM), the learning vector quantization (LVQ), the neural gas, and the ART model, and clustering algorithms such as the C-means, mountain/subtractive clustering, and fuzzy C-means (FCM) algorithms. Associated topics such as the under-utilization problem, fuzzy clustering, robust clustering, clustering based on non-Euclidean distance measures, supervised clustering, hierarchical clustering as well as cluster validity are also described. Two examples are given to demonstrate the use of the clustering methods.

Preliminary results of interstitial motexafin lutetium-mediated PDT for prostate cancer.

BACKGROUND AND OBJECTIVES: Interstitial photodynamic therapy (PDT) is an emerging modality for the treatment of solid organ disease. Our group at the University of Pennsylvania has performed extensive studies that demonstrate the feasibility of interstitial PDT for prostate cancer. Our preclinical and clinical experience is herein detailed. STUDY DESIGN/MATERIALS AND METHODS: We have treated 16 canines in preclinical studies, and 16 human subjects in a Phase I study, using motexafin lutetium-mediated PDT for recurrent prostate adenocarcinoma. Dosimetry of light fluence, drug level and oxygen distribution for these patients were performed. RESULTS: We demonstrate the safe and comprehensive treatment of the prostate using PDT. However, there is significant variability in the dose distribution and the subsequent tissue necrosis throughout the prostate. CONCLUSIONS: PDT is an attractive option for the treatment of prostate adenocarcinoma. However, the observed variation in PDT dose distribution translates into uncertain therapeutic reproducibility. Our future focus will be on the development of an integrated system that is able to both detect and compensate for dose variations in real-time, in order to deliver a consistent overall PDT dose distribution.

Binding of serum response factor to CArG box sequences is necessary but not sufficient to restrict gene expression to arterial smooth muscle cells.

Serum response factor (SRF) plays an important role in regulating smooth muscle cell (SMC) development and differentiation. To understand the molecular mechanisms underlying the activity of SRF in SMCs, the two CArG box-containing elements in the arterial SMC-specific SM22alpha promoter, SME-1 and SME-4, were functionally and biochemically characterized. Mutations that abolish binding of SRF to the SM22alpha promoter totally abolish promoter activity in transgenic mice. Moreover, a multimerized copy of either SME-1 or SME-4 subcloned 5' of the minimal SM22alpha promoter (base pairs -90 to +41) is necessary and sufficient to restrict transgene expression to arterial SMCs in transgenic mice. In contrast, a multimerized copy of the c-fos SRE is totally inactive in arterial SMCs and substitution of the c-fos SRE for the CArG motifs within the SM22alpha promoter inactivates the 441-base pair SM22alpha promoter in transgenic mice. Deletion analysis revealed that the SME-4 CArG box alone is insufficient to activate transcription in SMCs and additional 5'-flanking nucleotides are required. Nuclear protein binding assays revealed that SME-4 binds SRF, YY1, and four additional SMC nuclear proteins. Taken together, these data demonstrate that binding of SRF to specific CArG boxes is necessary, but not sufficient, to restrict transgene expression to SMCs in vivo.

Analysis of SM22alpha-deficient mice reveals unanticipated insights into smooth muscle cell differentiation and function.

SM22alpha is a 22-kDa smooth muscle cell (SMC) lineage-restricted protein that physically associates with cytoskeletal actin filament bundles in contractile SMCs. To examine the function of SM22alpha, gene targeting was used to generate SM22alpha-deficient (SM22(-/-LacZ)) mice. The gene targeting strategy employed resulted in insertion of the bacterial lacZ reporter gene at the SM22alpha initiation codon, permitting precise analysis of the temporal and spatial pattern of SM22alpha transcriptional activation in the developing mouse. Northern and Western blot analyses confirmed that the gene targeting strategy resulted in a null mutation. Histological analysis of SM22(+/-LacZ) embryos revealed detectable beta-galactosidase activity in the unturned embryonic day 8.0 embryo in the layer of cells surrounding the paired dorsal aortae concomitant with its expression in the primitive heart tube, cephalic mesenchyme, and yolk sac vasculature. Subsequently, during postnatal development, beta-galactosidase activity was observed exclusively in arterial, venous, and visceral SMCs. SM22alpha-deficient mice are viable and fertile. Their blood pressure and heart rate do not differ significantly from their control SM22alpha(+/-) and SM22alpha(+/+) littermates. The vasculature and SMC-containing tissues of SM22alpha-deficient mice develop normally and appear to be histologically and ultrastructurally similar to those of their control littermates. Taken together, these data demonstrate that SM22alpha is not required for basal homeostatic functions mediated by vascular and visceral SMCs in the developing mouse. These data also suggest that signaling pathways that regulate SMC specification and differentiation from local mesenchyme are activated earlier in the angiogenic program than previously recognized.