Long short-term memory and Logistic regression for mortality risk prediction of intensive care unit patients with stroke / 北京大学学报(医学版)

OBJECTIVE@#To select variables related to mortality risk of stroke patients in intensive care unit (ICU) through long short-term memory (LSTM) with attention mechanisms and Logistic regression with L1 norm, and to construct mortality risk prediction model based on conventional Logistic regression with important variables selected from the two models and to evaluate the model performance.@*METHODS@#Medical Information Mart for Intensive Care (MIMIC)-Ⅳ database was retrospectively analyzed and the patients who were primarily diagnosed with stroke were selected as study population. The outcome was defined as whether the patient died in hospital after admission. Candidate predictors included demogra-phic information, complications, laboratory tests and vital signs in the initial 48 h after ICU admission. The data were randomly divided into a training set and a test set for ten times at a ratio of 8 ∶2. In training sets, LSTM with attention mechanisms and Logistic regression with L1 norm were constructed to select important variables. In the test sets, the mean importance of variables of ten times was used as a reference to pick out the top 10 variables in each of the two models, and then these variables were included in conventional Logistic regression to build the final prediction model. Model evaluation was based on the area under the receiver operating characteristic curve (AUC), sensitivity, specificity, and accuracy. And the model performance was compared with the forward Logistic regression model which hadn't conducted variable selection previously.@*RESULTS@#A total of 2 755 patients with 2 979 ICU admission records were included in the analysis, of which 526 recorded deaths. The AUC of Logistic regression model with L1 norm was statistically better than that of LSTM with attention mechanisms (0.819±0.031 vs. 0.760±0.018, P < 0.001). Age, blood glucose, and blood urea nitrogen were at the top ten important variables in both of the two models. AUC, sensitivity, specificity, and accuracy of Logistic regression models were 0.85, 85.98%, 71.74% and 74.26%, respectively. And the final prediction model was superior to forward Logistic regression model.@*CONCLUSION@#The variables selected by Logistic regression with L1 norm and LSTM with attention mechanisms had good prediction performance, which showed important implications on the mortality prediction of stroke patients in ICU.

Efficacy of cellulose on functional constipation / 中华胃肠外科杂志

<p><b>OBJECTIVE</b>To assess the clinical efficacy and safety of cellulose on functional constipation.</p><p><b>METHODS</b>A prospective, self-controlled, multicenter clinical trial of cellulose was conducted for 2 weeks in 240 patients with functional constipation according to the Rome III( criteria. Symptoms and characters of feces before and after the treatment were observed and evaluated according to a score scheme.</p><p><b>RESULTS</b>In the 240 patients, the frequencies of defecation increased and the characters of feces was improved significantly after 2-week treatment. There were no adverse reactions observed throughout the clinical trial. The total efficacy was 82.1% at day 7 and 90.7% at day 14. The satisfactory rate of doctors was 83.8% and of patients was 83.8%.</p><p><b>CONCLUSION</b>Cellulose is effective and safe in the treatment of chronic functional constipation.</p>

Clinical application value of laryngeal electromyography and laryngeal somatosensory evoked potential in patients with recurrent laryngeal nerve paralysis by anterior elective cervical surgery / 中国骨伤

<p><b>OBJECTIVE</b>To determine the clinical evaluation role of laryngeal electromyography (LEMG) and laryngeal somatosensory evoked potential (LSEP) in the recurrent laryngeal nerve paralysis by anterior elective cervical surgery.</p><p><b>METHODS</b>LEMG and LSEP were determined in 18 patients with recurrent laryngeal nerve paralysis by anterior elective cervical surgery at the 1st, 2nd and 4th week after operation. The comparison between the normal control (18 health adults) and the results of LEMG and LSEP were analyzed.</p><p><b>RESULTS</b>The latency prolonged and the amplitude decreased of LSEP in all patients as compared with the control group. Furthermore, reinneration potential increased gradually in all patients at the 1st, 2nd and 4th week after operation (P<0.05). The results of LEMG showed increase of denervation potential. The higher the amplitude of LSEP and LEMG, the better the prognosis of the recurrent laryngeal nerve paralysis.</p><p><b>CONCLUSION</b>LEMG and LSEP might evaluate regenerate the degree of recurrent laryngeal nerve injury caused by anterior elective cervical surgery and predict the prognosis of the recurrent laryngeal nerve paralysis.</p>

Study on the factors influencing suicidal ideation among medical students in Beijing / 中华流行病学杂志

<p><b>OBJECTIVE</b>To evaluate the effects of personality-related health risk factors on suicidal ideation among medical students.</p><p><b>METHODS</b>1204 medical students at first grade were selected in Beijing, using random cluster sampling method. Data were obtained through health risk behaviors questionnaire, personality diagnostic questionnaire-4 (PDQ-4) and were analyzed by logistic regression method.</p><p><b>RESULTS</b>There were 12 risk factors selected from single factor analysis, including physical fight, physical abuse, physically forced to have sexual intercourse, sexual risk behaviors, tobacco and alcohol use behaviors, loneliness, bad mood, insomnia, feeling hopeless, higher PDQ-4 score and internet abuse behaviors. Data from Unconditional logistic regression showed that the main risk factors of suicide ideation were insomnia (OR = 4.98), physical abuse (OR = 4.43), sexual risk behaviors (OR = 2.63), bad mood (OR = 2.32), feeling hopeless (OR = 1.98), higher PDQ-4 score (OR = 1.09) in male students; while fighting (OR = 7.10), loneliness (OR = 4.42), physically forced to have sexual intercourse (OR = 4.19), internet abuse behaviors( OR = 1.39) in female students.</p><p><b>CONCLUSION</b>Suicidal ideation was associated with various factors, with significant gender difference.</p>

Role and significance of pelvic four-contrast defecography in the diagnosis of outlet obstructive constipation / 中华胃肠外科杂志

<p><b>OBJECTIVE</b>To study the changes in pelvic floor morphology and relationships of the pelvic organs in patients with outlet obstructive constipation (OOC).</p><p><b>METHODS</b>Fifty-nine OOC patients and 12 healthy volunteers were examined by simultaneous pelvic four-contrast defecography, including pelvicography, vaginal opacification, voiding cystography and defecography. The levels of perineum, peritoneum and bladder, and anorectal angle were measured and recorded.</p><p><b>RESULTS</b>Among the 59 OOC patients, 46 cases of internal rectal prolapse (IRP), 29 cases of pelvic floor hernia, 7 cases of rectocele (RC), 7 cases of spastic pelvic floor syndrome (SPFS), 5 cases of descending perineum syndrome were diagnosed by pelvic four-contrast defecography. Six cystoceles and 10 uterine prolapses were also found by pelvic four-contrast defecography. Compared with healthy volunteers, OOC patients had significantly large anorectal angles during defecation (P<0.05), abnormality descending of perineum during rest and defecation (P<0.05, P<0.01), and a deep pouch of Douglas during defecation (P<0.01). OOC patients combined with urinary system symptoms had an abnormal descent of the bladder during rest and defecation (P<0.05, P<0.01).</p><p><b>CONCLUSION</b>Pelvic four-contrast defecography is an effective method for the diagnosis of IRP, RC, pelvic floor hernia, peritoneocele, cystocele and uterine prolapse, and is helpful in the selection of proper surgical procedures for the treatment of OOC.</p>

Distribution and efficiency of recombinant adenovirus mediated human stem cell leukemia gene transfer in mice with interstitial cells of Cajal loss / 中华胃肠外科杂志

<p><b>OBJECTIVE</b>To investigate the construction of the green fluorescent protein (GFP) labeled recombinant adenovirus containing human stem cell leukemia (hSCL) and its distribution and efficiency in mice with interstitial cells of Cajal (ICC) loss.</p><p><b>METHODS</b>The recombinant adenovirus Ad-GFP/SCL was constructed by Ad-Easy system based on the homologous recombination in bacteria, then 1.6 x 10(9) PFU of recombinant adenoviruses were injected into Balb/c mice with ICC loss via the tail vein. In vivo distribution and efficiency of recombinant adenoviruses mediated hSCL were observed by GFP under the fluorescent microscope at different phases. The expression of SCL gene was measured by RT-PCR method. The damages were observed in different organs by HE staining.</p><p><b>RESULTS</b>The recombinant adenovirus containing hSCL was quickly constructed by homologous recombination in bacteria using Ad-Easy system. Under the fluorescent microscope, GFP was revealed in heart, lung, liver, spleen, kidney, small intestine and large intestine of mice with ICC loss at different phases. No obvious damages were observed in various visceral organs by HE staining. RT-PCR showed SCL mRNA expression in various visceral organs at different levels.</p><p><b>CONCLUSIONS</b>Construction of adenovirus vector by the homologous recombination in bacteria is an efficient and time saving method, and a high titer of adenovirus is able to mediate the safe and stable expression of SCL gene in mice with ICC loss. This finding will make further gene therapy in mice with STC possible.</p>

Comparative study between dynamic MRI and pelvic organography in diagnosis of pelvic floor disorders / 中华胃肠外科杂志

<p><b>OBJECTIVE</b>To evaluate the clinical value of simultaneously combined pelvic floor dynamic MRI and pelvic organography in diagnosing female pelvic floor disorders and search for the best imaging model for diagnosing pelvic floor disorders.</p><p><b>METHODS</b>Thirty women with pelvic floor disorders received pelvic floor dynamic MRI and simultaneously combined pelvic organography including cystourethrography, peritoneography, vaginography and defecography. Clinical diagnostic value was compared between this two methods.</p><p><b>RESULTS</b>The diagnostic accuracy of pelvic floor dynamic MRI and simultaneously combined pelvic organograph for cystocele,anorectal junction abnormal descent, pelvic floor hernia,uterocervical prolapse was 100%, 95.2 %, 86.7%, 85.7% respectively. Rectocele and prolapse of rectal were diagnosed by pelvic organograph in 12 and 28 cases respectively, while only 6 and 0 cases were diagnosed by pelvic floor dynamic MRI respectively. The mean examining time of pelvic floor dynamic MRI and simultaneously combined pelvic organography was (16 +/- 3)min, (34 +/- 9)min respectively (P< 0.01).</p><p><b>CONCLUSION</b>Pelvic floor dynamic MRI combined with defecography is the best imaging model for diagnosing pelvic floor disorders.</p>

Study on distribution of interstitial cells of Cajal in the sigmoid colon of patients with slow transit constipation / 中华外科杂志

<p><b>OBJECTIVE</b>Slow transit constipation (STC) is a colonic motor disorder whose etiology remains unclear. Recent studies have demonstrated a crucial role for interstitial cells of Cajal (ICC) in regulation of intestinal motility. The aim of this study was to examine the distribution of ICC within the normal sigmoid colon and STC patients.</p><p><b>METHODS</b>Twelve patients with STC and eight age-matched controls were studied. ICC were identified with a monoclonal antibody to c-kit by an indirect immunofluorescence method. Immunostained tissues were examined with a laser scanning confocal microscope and the area occupied by ICC was calculated with image analysis software.</p><p><b>RESULTS</b>ICC were located in the external muscle layers including longitudinal muscle (LM), myenteric plexus (MP), circular muscle (CM) and submucosal border (SMB). Two types of Kit-positive ICC were observed: bipolar cells characterized by one or two long processes, and multipolar cells with long stellate processes extending in various directions. A higher percentage of ICC was present in the MP regions and CM layers compared with the SMB and LM layers. Tissues from STC patients showed considerably decreased in number of ICC located in the four regions (ICC-LM, ICC-MP, ICC-CM, ICC-SMP), especially for ICC-SMP, almost completely disappeared.</p><p><b>CONCLUSION</b>Decreased c-kit + ICC in number may play an important role in the pathophysiology of STC. It remains to be determined whether loss of ICC is primary or secondary to another lesion.</p>