Linlin Chen

Predictors of Clinical and Endoscopic Findings in Differentiating Crohn's Disease from Intestinal Tuberculosis

BackgroundThere are many similarities and overlaps in clinical manifestations and ileocolonoscopic features between Crohn’s disease (CD) and intestinal tuberculosis (ITB). Differentiation between CD and ITB is of great importance.AimTo investigate the values of clinical and endoscopic findings in differential diagnosis between CD and ITB.MethodsClinical and endoscopic features of a cohort of 130 cases of CD and 122 cases of ITB from June 2003 to February 2009 were retrospectively reviewed following predetermined criteria. Parameters were screened by logistic regression analysis. Furthermore, the diagnostic efficacy of screened parameters was analyzed by regression equation (mathematical model) and receiver operating characteristic curve (ROC curve).ResultsThe clinical features helpful in differentiating CD from ITB are hematochezia, intestinal surgery, perianal diseases, pulmonary tuberculosis, ascites, and positive of PPD skin test; the sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of regression mathematical model established by clinical features were 90.3, 76.8, 83.8, 80.7, and 88.0%, respectively. The endoscopic features helpful in differentiating CD from ITB were rectum involved lesions, longitudinal ulcer, cobblestone appearance, fixed-open ileocecal valve, transverse ulcer, and rodent ulcer; the sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of regression mathematical model established by endoscopic features were 82.9, 82.0, 82.5, 82.9, and 82.0%, respectively.ConclusionsIt was proposed that a diagnostic algorithm based on available clinical and endoscopic regression equation could improve the current sensitivity, specificity, and accuracy in differentiating between CD from ITB.

Lactobacillus acidophilus Suppresses Colitis-Associated Activation of the IL-23/Th17 Axis

The aim of this paper is to determine the modulatory effects of Lactobacillus acidophilus on the IL-23/Th17 immune axis in experimental colitis. DSS-induced mouse models of UC were to be saline, hormones, and different concentrations of Lactobacillus acidophilus intervention. The expression of interleukin- (IL-) 17, tumor necrosis factor α (TNFα), IL-23, transforming growth factor β1 (TGFβ1), signal transducer and activator of transcription 3 (STAT3), and phosphorylated (p)-STAT3 was examined by RT-PCR, Western blotting, and immunohistochemical analysis. And the results showed that administration of L. acidophilus suppressed Th17 cell-mediated secretion of proinflammatory cytokine IL-17 through downregulation of IL-23 and TGFβ1 expression and downstream phosphorylation of p-STAT3.

Efficacy profiles for different concentrations of Lactobacillus acidophilus in experimental colitis.

AIM To determine the efficacy profiles of different concentrations of Lactobacillus acidophilus (L. acidophilus) for treating colitis using an experimental murine model. METHODS Colitis was established in 64 BALB/c mice by adding 5% dextran sodium sulfate (DSS) to the drinking water and allowing ad libitum access for 7 d. The mice were then randomly divided into the following control and experimental model groups (n = 8 each; day 0): untreated model control; negative-treatment model control (administered gavage of 1 mL/10 g normal saline); experimental-treatment models C4-C8 (administered gavage of 10(4), 10(5), 10(6), 10(7), or 10(8) CFU/10 g L. acidophilus, respectively); positive-treatment model control (administration of the anti-inflammatory agent prednisone acetate at 45 μg/10 g). Eight mice given regular water (no DSS) and no subsequent treatments served as the normal control group. Body weight, fecal traits, and presence of fecal occult blood were assessed daily. All animals were sacrificed on post-treatment day 7 to measure colonic length, perform histological scoring, and quantify the major bacteria in the proximal and distal colon. Intergroup differences were determined by one-way ANOVA and post-hoc Student-Newman-Keuls comparison. RESULTS All treatments (L. acidophilus and prednisone acetate) protected against colitis-induced weight loss (P < 0.05 vs model and normal control groups). The extent of colitis-induced colonic shortening was significantly reduced by all treatments (prednisone acetate > C4 > C5 > C7 > C8 > C6; P < 0.05 vs untreated model group), and the C6 group showed colonic length similar to that of the normal control group (P > 0.05). The C6 group also had the lowest disease activity index scores among the model groups. The bacterial profiles in the proximal colon were similar between all of the experimental-treatment model groups (all P > 0.05). In contrast, the bacterial profile in the distal colon of the C6 group showed the distinctive features (P < 0.05 vs all other experimental-treatment model groups) of Lactobacillus sp. and Bifidobacterium sp. being the most abundant bacteria and Staphylococcus aureus being the least abundant bacteria. CONCLUSION The most therapeutically efficacious concentration of L. acidophilus (10(6) CFU/10 g) may exert its effects by modulating the bacterial profile in the distal colon.

Lactobacillus species shift in distal esophagus of high-fat-diet-fed rats

AIM To analyze the microbiota shift in the distal esophagus of Sprague-Dawley rats fed a high-fat diet. METHODS Twenty Sprague-Dawley rats were divided into high-fat diet and normal control groups of 10 rats each. The composition of microbiota in the mucosa from the distal esophagus was analyzed based on selective culture. A variety of Lactobacillus species were identified by molecular biological techniques. Bacterial DNA from Lactobacillus colonies was extracted, and 16S rDNA was amplified by PCR using bacterial universal primers. The amplified 16S rDNA products were separated by denaturing gradient gel electrophoresis (DGGE). Every single band was purified from the gel and sent to be sequenced. RESULTS Based on mucosal bacterial culturing in the distal esophagus, Staphylococcus aureus was absent, and total anaerobes and Lactobacillus species were decreased significantly in the high-fat diet group compared with the normal control group (P < 0.01). Detailed DGGE analysis on the composition of Lactobacillus species in the distal esophagus revealed that Lactobacillus crispatus, Lactobacillus gasseri (L. gasseri) and Lactobacillus reuteri (L. reuteri) comprised the Lactobacillus species in the high-fat diet group, while the composition of Lactobacillus species in the normal control group consisted of L. gasseri, Lactobacillus jensenii and L. reuteri. CONCLUSION High-fat diet led to a mucosal microflora shift in the distal esophagus in rats, especially the composition of Lactobacillus species.

Chronic active Epstein–barr virus infection associated with hemophagocytic syndrome and extra-nodal natural killer/t-cell lymphoma in an 18-year-old girl: A case report

Rationale: Chronic active Epstein–Barr virus infection (CAEBV) associated with hemophagocytic syndrome (HPS) and extra-nodal natural killer (NK)/T-cell lymphoma (ENKL) is a rare life-threatening disorder. This disease is easily misdiagnosed because of its varied presentations. Patient concerns: An 18-year-old girl was admitted to our hospital with a history of edema in the lower limbs and intermittent fever lasting for more than 1 month. At admission, she had severe liver injury of unknown etiology. Laboratory test results revealed pancytopenia, hyperferritinemia, hypertriglyceridemia, and hypofibrinogenemia. Results of serologic tests for EBV were positive. Results of a skin biopsy indicated EBV-positive NK/T-cell lymphoma, and bone marrow aspiration revealed focal hemophagocytosis and atypical lymphoid cells. Diagnosis: On the basis of these findings, we diagnosed the case as extra-nodal NK/T-cell lymphoma-associated HPS (natural killer/T-cell lymphoma-associated hemophagocytic syndrome), which is commonly induced by CAEBV. Interventions: Treatment consisted of general management of hepatitis, supplemented with albumin and empirical antibiotic therapy. Outcomes: The patient died from massive gastrointestinal hemorrhage a week after she was discharged from the hospital. Lessons: ENKL and HPS present with varied features and are generally fatal; therefore, clinicians should proceed with caution in suspected cases. HPS should be considered when the patient presents with fever, hepatosplenomegaly, pancytopenia, and liver failure. When HPS is suspected, clinicians should determine the underlying cause, such as severe infection, including infection with viruses such as EBV; genetic predisposition; or underlying malignancies, especially lymphoma because of its strong association with HPS.

Antitumor mechanisms of bifidobacteria (Review)

Cancer remains one of the most common causes of mortality globally. Chemotherapy, one of the major treatment strategies for cancer, primarily functions by targeting the cancer cells and affecting them physiologically, but also affects normal cells, which is a major concern at present. Therefore, adverse effects of chemotherapy drugs, including myelosuppression and liver and kidney damage, are of concern. Now, microbial products have attracted attention in cancer treatment research. Notably, carcinogenesis is considered to be associated with microbial dysbiosis, particularly the positive antitumor effects of bifidobacteria. Although there remains a substantial amount to be understood about the regulation of bifidobacteria, bifidobacteria remain an attractive and novel source of cancer therapeutics. The present review focuses on introducing the latest information on the antitumor effects of bifidobacteria and to propose future strategies for using bifidobacteria in the development of cancer therapeutics.

Chronic diarrhea associated with high serum level of immunoglobulin A and diffuse infiltration of plasma cell in small intestine: A case report.

Rationale: Chronic diarrhea in adult patients due to various causes is very common in clinic, but patient suffering with mal-absorption due to immunoproliferative small intestinal disease was rarely reported in China. Patient concerns and Diagnoses: A 35-year-old female presented with more than three years history of chronic diarrhea, rickets, high serum value of immunoglobulin A protein, and anemia. Bone marrow aspiration suggested that the patient was in a sideropenic and megalobastic anemia stage. Duodenal and ileac biopsies revealed atrophy and blunting villi. The bowel lamina propria was infiltrated with slightly increased intraepithelial lymphocytes and mainly with diffuse plasma cells. The following enzyme labeling immunohistochemistry results were strongly positive to alpha-heavy-chain. Computed tomography manifested she had diffuse thickening of small intestine wall. At last a diagnosis of immunoproliferative small intestinal disease was made. Interventions and Outcomes: On the first month, the patient was treated with vitamin D supplements, calcium, magnesium, potassium, iron, folic acid, mecobalamin replacements and microflora probiotics. The patient frequency of water diarrhea alleviated slightly, but her weight loss, anxiety neurosis and other disorders were still severe. After taking with prednisone (40 mg per day, and gradually reduced to the lowest dose) for another month, the symptoms was gradually subsided. Lessons: The study shows that immunohistochemical staining for alpha-heavy chain proteins should be completed on small intestine biopsy specimens if the patient is suspected a diagnosis of immunoproliferative small intestinal disease.