As an osmotic laxative, lactulose has been widely used in the treatment of digestive system diseases. In recent years, with the in-depth study of intestinal microbiota and microecology, the prebiotics effect of lactulose has attracted widespread attention. Exploring the prebiotics effect of lactulose is helpful for the understanding of specific mechanism of disease treatment. This article reviewed the value of prebiotics effect of lactulose in the treatment of digestive system diseases.

Objective To improve the knowledge and early diagnostic rate of primary small intestinal tumor.Methods From August 2012 to August 2017,hospitalized patients with pathological diagnosis of primary small intestinal tumor (excluding duodenal neoplasm) from Peking Union Medical College Hospital were retrospectively enrolled.The data of clinical manifestations,laboratory examinations,imaging,endoscopy examination,pathological findings and treatment were collected and analyzed.Results A total of 180 patients with primary small intestinal tumor were enrolled.The common clinical manifestations included abdominal pain (76 cases,42.2 ％),gastrointestinal bleeding (64 cases,35.6％),and abdominal distension (30 cases,16.7％),and 22 (12.2％) patients had no overt clinical symptoms.The sensitivity of carbohydrate antigen 19-9 (CA19-9) in the diagnosis of small bowel adenocarcinoma was 57.1％ (12/21).The diagnostic rates of computed tomography enterodysis (CTE),positron-emission computed tomography (PET)/computed tomography (CT),and abdominopelvic enhanced CT were 96.5％ (83/86),100.0％ (29/29),and 91.5％ (43/47),respectively.The diagnostic small intestinal tumor patients of barium radiography (14 cases),abdominopelvic magnetic resonance imaging (MRI) (eight cases),small bowel endoscopy (18 cases) and capsule endoscopy (eight cases) were seven,six,fifteen and six cases,respectively.Among 180 patients,14 (7.8％) patients were considered gynecological tumors by imaging examination before surgery,seven (3.9％) patients underwent emergency operation because of intestinal obstruction,four (2.2％) patients underwent emergency surgery due to gastrointestinal bleeding,and four (2.2％) patients underwent emergency surgery because of intestinal perforation.Histopathological type included gastrointestinal stromal tumor (117 cases,65.0％),lymphoma (25 cases,13.9％) and adenocarcinomas (21 cases,11.7％).Except seven patients with intestinal lymphoma who received chemotherapy,the rest 173 patients underwent surgical resection.Conclusions Primary small bowel tumor has no specific clinical manifestations.It should be alert on patients without positive findings by regular gastroendoscopy and colonendoscopy examination but with symptoms of abdominal pain,gastrointestinal bleeding and intestinal obstruction.CTE should be the first choice for patients with symptoms but unclear diagnosis.

Objective:Clinicopathological characteristics of neuroendocrine neoplasms are highly heterogeneous based on variable origins.Our study aims to explore the clinical features of rectal neuroendocrine neoplasm (RNEN).Methods:Patients with histologically diagnosed rectal neuroendocrine neoplasms were retrospectively analyzed between January 2012 and December 2020. Epidemiological characteristics, clinical manifestations, complete blood count, endoscopy findings, and pathological features were recorded and analyzed. T-test was used for measurement data analysis, Chi-square test was performed for classification data analysis, and Binary logistic regression was applied for analyzing risk factors of metastasis.Results:Among 172 patients, the male to female ratio was 107 to 65 with an average age of (52±12) years (16-77 years). Altered bowel habit was the most common initial symptom (58/172, 33.7%), followed by abdominal pain (36/172, 20.9%) and loss of body weight (27/172, 15.7%). One hundred and sixty-one cases were neuroendocrine tumors, 9 were neuroendocrine carcinomas and 2 were mixed neuroendocrine-non-neuroendocrine neoplasms. Most endoscopic presentations were polypoid lesions (147/172, 85.5%), mainly limited to mucosa (48/172, 27.9%) and submucosa (96/172, 55.8%). Twenty-nine patients developed lymph node invasion or distant metastasis at diagnosis. There were statistical difference of neutrophil-to-lymphocyte ratios (NLR) among groups with different tumor size (<10 mm vs. 10-20 mm vs.>20 mm, mean NLR 1.79±0.55 vs. 2.27±1.23 vs. 2.95±0.66, P<0.01. Compared with non-metastatic group, the metastatic group presented higher NLR(2.61±0.81 vs. 1.89±0.80, P<0.01). Tumor size (<10 mm vs. 10-20 mm vs.>20 mm, OR 1.00 vs. 2.10 vs. 5.25×10 9, P =0.001), invasion to bowel wall (mucosa vs. submucosa vs. muscularis vs. serosa invasion, OR 1.00 vs. 3.26 vs. 14.11 vs. 39.42, P=0.008), and NLR (NLR<2.25 vs. NLR≥2.25, OR 1.00 vs. 5.19, P =0.024) were risk factors for metastasis. Conclusion:Metastasis of RNEN is related with tumor size, degree of bowel invasion and NLR. High NLR is a poor prognostic factor of RNEN.