[Analysis of the incidence and symptomatology of low anterior resection syndrome after laparoscopic anterior resection for rectal cancer].

Objective: This study aims to explore the temporal trend of Low Anterior Resection Syndrome (LARS) and its symptoms after laparoscopic anterior resection for rectal cancer. Methods: A retrospective cohort study design was employed. The study included primary rectal (adenocarcinoma) cancer patients who underwent laparoscopic anterior resection at Tongji Hospital, Huazhong University of Science and Technology, between January 1, 2010, and December 31, 2020. Complete medical records and follow-up data at 3, 6, 9, 12, and 18 months postoperatively were available for all patients. A total of 1454 patients were included, of whom 1094 (75.2%) were aged ≤65 years, and 597 (41.1%) were females. Among them, 1040 cases (71.5%) had an anastomosis-to-anus distance of 0-5cm, and 86 cases (5.9%) received neoadjuvant treatment. All patients completed the Chinese version of the LARS questionnaire and their LARS occurrence and specific symptom information were recorded at 3, 6, 9, 12, and 18 months postoperatively. Considering past literature and clinical experience, further subgroup analyses were performed to explore the potential impact factors on severe LARS, including anastomosis level, preoperative neoadjuvant therapy, postoperative adjuvant therapy, and the presence of preventive stoma. Results: The occurrence rates of LARS at 3, 6, 9, 12, and 18 months postoperatively were 78.5% (1142/1454), 71.4% (1038/1454), 55.0% (799/1454), 45.7% (664/1454), and 45.7% (664/1454), respectively (χ2=546.180, P<0.001). No statistically significant difference was observed between the 12-month and 18-month time points (P>0.05). When compared with the symptoms at 3 months, the occurrence rates of gas incontinence [1.7% (24/1454) vs. 33.9% (493/1454)], liquid stool incontinence [3.9% (56/1454) vs. 41.9% (609/1454)], increased stool frequency [79.6% (1158/1454) vs. 95.9% (1395/1454)], stool clustering [74.3% (1081/1454) vs. 92.9% (1351/1454)], and stool urgency [46.5% (676/1454) vs. 78.7% (1144/1454)] in the LARS symptom spectrum were significantly alleviated at 12 months (all P<0.05) and remained stable beyond 12 months (all P>0.05). With the extension of postoperative time, the incidence rates of severe LARS exhibited a decreasing trend in different subgroups, of anastomosis level, preoperative neoadjuvant therapy, postoperative adjuvant therapy, and the presence of preventive stoma, and reached stability at 12 months postoperatively (all P>0.05). Conclusion: LARS and its specific symptom profile showed a trend of gradual improvement over time up to 1 year postoperatively, and stabilized after more than 1 year. Increased stool frequency and stool clustering are the most common features of abnormal bowel dys function, which improve slowly after surgery.

Correction: Exosomal Wnt-induced dedifferentiation of colorectal cancer cells contributes to chemotherapy resistance.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Exosomal Wnt-induced dedifferentiation of colorectal cancer cells contributes to chemotherapy resistance.

Cancer stem cells (CSCs) are inherently resistant to chemotherapy, and CSCs in chemotherapy-failed recurrent tumors are enriched; however, the cellular origin of chemotherapy-induced CSC enrichment remains unclear. Communication with stromal fibroblasts may induce cancer cell dedifferentiation into CSCs through secreted factors. We recently demonstrated that fibroblast-derived exosomes promote chemoresistance in colorectal cancer (CRC). Here, we report that fibroblasts confer CRC chemoresistance via exosome-induced reprogramming (dedifferentiation) of bulk CRC cells to phenotypic and functional CSCs. At the molecular level, we provided evidence that the major reprogramming regulators in fibroblast-exosomes are Wnts. Exosomal Wnts were found to increase Wnt activity and drug resistance in differentiated CRC cells, and inhibiting Wnt release diminished this effect in vitro and in vivo. Together, our results indicate that exosomal Wnts derived from fibroblasts could induce the dedifferentiation of cancer cells to promote chemoresistance in CRC, and suggest that interfering with exosomal Wnt signaling may help to improve chemosensitivity and the therapeutic window.

The use of susceptibility-weighted imaging to detect cerebral microbleeds after lacunar infarction.

OBJECTIVE: To study the value of susceptibility-weighted imaging (SWI) technology to detect cerebral microbleeds (CMBs) in senile cerebral lacunar infarction patients; and to evaluate the complicated cerebral hemorrhage risk after patients with CMBs took aspirin, an antiplatelet medication or received anticoagulant therapy. PATIENTS AND METHODS: MRI scanning, using GRE-T2*WI, SWI and FSE sequences (T1WI, T2WI, and T2FLAIR), was performed on the three groups: (1) a cerebral lacunar infarction group; (2) cerebral lacunar infarction with cerebral microbleeds (CMBs) group; and (3) a healthy elderly group. A total of 60 cases were in each group (180 total patients). In addition, the lacunar infarction group and lacunar infarction with CMBs groups were both treated with formal antiplatelet or anticoagulant therapy, according to medical guidelines. Patients were followed for 12 months, during which time their cerebral hemorrhages and post-event effects were observed. The relativity of CMBs, antiplatelet therapy, anticoagulant therapy and cerebral hemorrhage transformation was analyzed and defined. The two groups of research patients with lacunar infarctions were scanned with relevant sequences. RESULTS: The SWI scanning sequence showed the highest positive rate of CMBs, followed by GRE-T2*WI and other conventional scanning sequences. T1WI, T2WI and T2FLAIR showed a relatively lower positive rate of CMBs. In the cerebral lacunar infarction group and healthy elderly group, 34 cases in the SWI sequence showed 84 positive sites; 18 cases in the GRE-T2*WI sequence showed 40 positive sites; 2 cases in the T1WI sequence showed 4 positive sites; and 6 cases in the T2WI sequence showed 11 positive sites. After a chi-squared test, the differences between the sequences were statistically significant (p < 0.05). In the lacunar infarction group, 26 cases (43.33%) exhibited microbleeding lesions, while the normal control group represented 8 cases (13.33%). The lacunar infarction group exhibited mild, moderate and severe cases, the three types of CMBs. The normal control group only showed mild hemorrhaging. The degree of lacunar infarction was significantly related to the severity of CMBs (p < 0.05). After patients with CMBs had received formal antiplatelet therapy and anticoagulation therapy, one case in the lacunar infarction with microbleeds group showed cerebral hemorrhaging, but this had no statistical significance (p > 0.05). CONCLUSIONS: The SWI scanning sequence is more sensitive than the GRE-T2*WI sequence. The GRE-T2*WI sequence is more sensitive than the conventional FSE sequence. SWI is highly sensitive and specific to the diagnosis of CMBs. It is an accurate and effective method for the analysis and diagnosis of CMBs. If patients with CMBs caused by lacunar infarction are treated with antiplatelet and anticoagulant therapy, the risk of cerebral hemorrhagic transformation is relatively smaller within 12 months. However, this needs to be observed further to define possible long-term risks.

The effect of dehydroepiandrosterone (DHEA) supplementation on women with diminished ovarian reserve (DOR) in IVF cycle: Evidence from a meta-analysis.

To evaluate the effect of dehydroepiandrosterone (DHEA) therapy on the ovarian response and pregnancy outcome in patients with diminished ovarian reserve (DOR). Eligible studies, published before August 31, 2015, were identified from PubMed, EMBASE, the Cochrane library. Outcome measures were the number of retrieved oocytes, cancellation rate of IVF cycles, clinical pregnancy rate and miscarriage rate. We adopted Revman 5.0 software to pool the data from the eligible studies. A total of 9 studies, four were RCTs, four retrospective studies, one prospective studies, including 540 cases and 668 controls, were available for analysis. The pooled analysis showed that the clinical pregnancy rates were increased significantly in DOR patients who were pre-treated with DHEA (OR=1.47, 95% CI: 1.09-1.99), whereas no differences were found in the number of oocytes retrieved, the cancellation rate of IVF cycles and the miscarriage rate between the cases and controls (WMD= -0.69, 95% CI: -2.18-0.81; OR=0.74, 95% CI: 0.51-1.08; OR=0.34, 95% CI: 0.10-1.24). However, it is worth noting that when data were restricted to RCTs, there was a non-significant difference in the clinical pregnancy rate (OR=1.08, 95% CI: 0.67-1.73). We concluded that DHEA supplementation in DOR patients might improve the pregnancy outcomes. To further confirm this effect, more randomized controlled trials with large sample sizes are needed.

[Regulation of purine biosynthetic genes expression in Salmonella typhimurium].

To study binding funtion of 4 consensus bases in 16 bp PUR box with purR protein, the directed site mutation for each was carried out, which mutate from C to G, A to G, A to G, T to C, respectively. Gel retardation showed that the PUR box carrying a reserved mutation could not bind with purR protein. It suggested that all these consensus base pairs are necessary to hold the normal binding function of PUR box with purR protein.

High-level expression of human butyrylcholinesterase gene in Bombyx mori and biochemical-pharmacological characteristic study of its product.

The human butyrylcholinesterase (BChE, EC 3.1.1.8) gene was highly expressed in Bombyx mori using baculovirus vector, and the biochemical-pharmacological properties of its product were studied. BChE cDNA was cloned into transfer vector pBn96 and co-transfected with wild-type Bombyx mori nucleopolyhedrovirus (BmNPV) DNA into BmN cells. The recombinant virus with the highest enzyme activity was sorted out and purified. Once the BmN cells or silkworm larvae had been infected with the recombinant virus, recombinant human BChE (rhBChE) could be secreted into the culture medium or the hemolymph of the larvae at levels of 1.5 mg x L(-1) and 35 mg x L(-1), respectively. Western blot and enzymatic staining of the electrophoresis gel of non-denatured protein showed that rhBChE manifested similar antigenicity and enzyme activity to native human BChE (nhBChE). The production of rhBChE in the hemolymph was 23-fold higher than that in BmN cells and about 280-fold that in Chinese hamster overy cells (125 microg x L(-1)). This is the first report of human BChE expression in silkworm with the highest level of yield so far. rhBChE was highly similar to nhBChE in respect to substrate affinity, inhibitor sensitivity, and reactivity of the inhibited enzyme. It is suggested that rhBChE functions as well as nhBChE and has potential practical value.

Effects of rhM-CSF expressed in silkworm on cytokine productions and membrane molecule expressions of human monocytes.

AIM: To study the effects of recombinant human macrophage colony-stimulating factor (rhM-CSF) expressed in silkworm on cytokine productions and membrane molecule expressions of monocytes. METHODS: The rhM-CSF was added to the human peripheral blood monocyte cultures and 3 d later, the culture supernatants and cells were collected, respectively. TNF-alpha, IL-6, IL-8, and IFN-alpha levels in the supernatants were detected by biological activity test or ELISA and expressions of CD11b, CD16, HLA I, and HLA II on the cellular surface were examined by the method of alkaline phosphatase anti-alkaline phosphatase complex (APAAP). RESULTS: The rhM-CSF promoted TNF-alpha, IL-6, and IL-8 inductions of monocytes and increased the percentages of CD11b, CD16, HLA I, and HLA II molecule expression on monocytes. CONCLUSION: The rhM-CSF plays a role in monocyte function up-regulation and has a certain practical value in immunological therapy.

[Expression regulation of purine biosynthetic genes in Salmonella typhimurium. VI. Isolation and characterization of super-repressor mutants].

Starting from strain of Salmonella typhimurium purD::lac, 86 exponential cultures were mutagenized with NTG and white or light blue clones on E + ado + Xgal plate were selected as candidates of purRs mutant. Total 66 independent candidate strains were obtained. By assaying their beta-galactosidase activity under the repressed and derepressed conditions, determining their frequency of revertional mutation, Conducting transductional analysis of mutational site and dorminance test, 11 candidates strains were proved to be super-repressor mutants. These mutants are useful for studying the expression of purine biosynthetic gene and relationship between protein structure and function in general.

Studies on the control region of the p10 gene of the Autographa californica nuclear polyhedrosis virus.

5' deletion mutants of the Autographa californica nuclear polyhedrosis virus very late p10 gene promoter have been prepared and subjected to a transient expression assay in infected Spodoptera frugiperda cells. The control plasmid contained the chloramphenicol acetyltransferase (CAT) reporter gene under the control of the p10 promoter, which was included in a 230 bp sequence upstream from the p10 translation initiation codon. The control plasmid also contained a segment of the hr5 enhancer downstream from the CAT gene. Promoter activity was unaffected by 5' deletion to position -77, which lies about 11 bp upstream from the p10 cap site. However, deletion of 12 more bp completely eliminated p10 promoter activity. Thus, the 5' border of the p10 promoter lies downstream from position -77, and the region between positions -77 and -65 contains an element that is important to promoter activity. This is the region that is conserved near the cap sites of late baculovirus genes. Our studies also show that transient expression of CAT under the control of the p10 promoter and hr5 enhancer is higher when transfection occurs prior to infection by virus.

The production and assessment of a plastic rod for the Chinese Reference Preparation for Opacity.

A reference preparation for opacity consisting of a plastic rod was introduced by Perkins et al. in 1973. It was adopted as the International Reference Preparation for Opacity in 1975. This plastic rod opacity reference preparation has been used to standardize the Chinese National Bacterial Opacity Standard. The material was prepared from plastic sheet by a water-bath method and by a dry-heat method; the sheet was then machined into the plastic rods. We have studied the technical processes and set up methods for the examination of the sheets and rods. The water-bath method was found to be better than the dry-heat method in our tests. Collaborative assays in research institutes of biological products have shown that the plastic rod can replace the glass-powder suspension. The duration of validity of the plastic rod opacity reference preparation and that of the glass-powder suspension used for the Chinese National Bacterial Opacity Standard were studied and found to be similar. For this reason the plastic rod opacity reference preparation has not been widely used in China.

Nucleotide sequence of a portion of the Autographa californica nuclear polyhedrosis virus genome containing the EcoRI site-rich region (hr5) and an open reading frame just 5' of the p10 gene.

The nucleotide sequence of a 1587 bp region lying within the HindIII-Q fragment of Autographa californica multiple nucleocapsid nuclear polyhedrosis virus (AcMNPV) DNA has been determined. It begins in the EcoRI-S-EcoRI-X region, continues to the HindIII-P/Q boundary and contains an open reading frame that codes for a polypeptide of 240 amino acids (p26). This open reading frame is also included in the 1100 and 1500 base transcripts previously mapped to this region. The sequence reveals that the 5' ends of the 1100 and 1500 base transcripts are located 20 bp downstream from the end of a putative TATA box (TAATTAAAT) and 19 bp upstream from the translation start codon (ATG) of the p26 open reading frame. The translation termination codon (TAA) falls in the immediate 5' flanking region of the major late p10 gene of AcMNPV, 3 bp downstream from the putative TATA box. The probable polyadenylation site for the 1100 base transcript lies 23 bp downstream from the cap site for the 750 and 2500 base transcripts encoding the p10 protein. The 5' flanking region of the p26 open reading frame contains the EcoRI site-rich region, hr5, whose sequence is included here. The EcoRI site-rich region, hr5, consists of six imperfect tandem repeats of a sequence that includes the EcoRI recognition site. These direct repeats also include many inverted repeats.