Structural and functional profiles of the gut microbial community in polycystic ovary syndrome with insulin resistance (IR-PCOS): a pilot study.

Polycystic ovary syndrome (PCOS) is a complex endocrine and metabolic disorder that affects 9-21% of reproductive-aged women. Affected women frequently display obesity, insulin resistance, and inflammation. Altered gut microbial community has been reported in PCOS and obese PCOS patients. However, the profile of the gut microbial community in insulin resistant PCOS (IR-PCOS) patients still remains unknown. In this study, next-generation sequencing based on the 16S rRNA gene was used to compare the gut microbial composition of women with IR-PCOS (n = 9, PCOS with insulin resistance), NIR-PCOS (n = 8, PCOS alone) and healthy controls (n = 8, HC). We assessed that the composition of the gut microbial communities in NIR-PCOS and IR-PCOS patients were significantly altered. The family Bacteroidaceae was prolific in the NIR-PCOS group and reached its highest level in the IR-PCOS group, while the Prevotellaceae dramatically decreased in PCOS patients, especially in the IR-PCOS group. Subsequent correlation analysis revealed that the increased clinical parameter levels, including insulin resistance, sex-hormones and inflammation, were positively associated with the abundance of Bacteroidaceae, but negatively associated with that of Prevotellaceae. In addition, IR-PCOS patients also displayed a significant difference in their amounts of Ruminococcaceae and Lachnospiraceae when compared to the NIR-PCOS group. Moreover, the functional prediction from PICRUSt revealed that 73 pathways are significantly changed in the gut microbial communities of PCOS patients. Specifically, 21 metabolism-associated pathways, including the steroid hormone biosynthesis and lipopolysaccharide biosynthesis pathways, are obviously changed in IR-PCOS when compared to NIR-PCOS and HC groups. Taking this into consideration, our present study suggests that the dysbiosis of gut microbial communities occurred most notably in IR-PCOS patients, and the difference in gut dysbiosis profile between the IR-PCOS and NIR-PCOS should be considered in clinical treatment for PCOS patients and future drugs development.

[Preparation of multivalent egg yolk IgY antibodies against Helicobacter pylori].

Objective To prepare a specific multivalent immunoglobulin of yolk (IgY) against multi-virulence factors of Helicobacter pylori (Hp). Methods The purified recombinant BabA2, UerB and FlaA of Hp were mixed equally with adjuvant, and then used to immunize egg-laying hens to produce specific multivalent IgY. Next, the biological characteristics of purified IgY were analyzed by SDS-PAGE, Western blot and ELISA. To analyze the inhibition effects of multivalent IgY on the growth of Hp in vitro, Hp was co-cultured with different final concentration of IgY (1, 5, 10) mg/mL in the presence or absence of antibiotics. Results After immunization, the titer of egg yolk IgY reached up to 1:150 000. Furthermore, the bacteriostasis assay showed that the multivalent IgY had a significant inhibitory effect on the growth of Hp at 5 mg/mL, and the combination with amoxicillin could further inhibited the growth of Hp. Conclusion The specific multivalent IgY against Hp is successfully prepared.

Neisseria flavescens: A Urease-Expressing Potential Pathogen Isolated from Gastritis Patients.

Parasitic pathogens, such as H. pylori (Helicobacter pylori), are considered as primary elements for causing stomach infection and leading to chronic gastritis or ulcers. Here, an unreported urease- and oxidase-producing Neisseria flavescens-like bacteria was isolated from the gastroscopic biopsies of 14C-UBT-positive gastritis patients. The isolate expressed the activity of urease, which is a pathogenic factor and considered as a reliable marker for diagnosis of H. pylori infection. However, the isolate didn't express the key functional genes of H. pylori including vacA and hpaA, and also the morphological feature of isolate was significantly different with H. pylori. Eventually, the 16S rDNA of isolate was sequenced and its sequence shared about 99.8% similarity with the N. flavescens standard strains, but about 20.8% similarity with the H. pylori. Further study of antibiotics-resistance revealed the N. flavescens isolate is high resistant to metronidazole, but highly sensitive to ampicillin sodium. To summarize, a urease-expressing N. flavescens strain was isolated and identified from Chinese gastritis patients; the encouraging results provides an important reference for the further study of its pathogenicity and the reasonable diagnosis and use of antibiotics clinically.

[Rapid determination of silicon content in black liquor of straw fibrous material].

The present paper reports a novel method for the determination of silicon content in straw fibrous material black liquor based on alpha-Si--Mo heteropoly acid spectrophotometry. The selected conditions were as follows: detection wavelength 360 nm, pH 4.0, and reaction time 10 min. It was found that the acidic soluble lignin in the sample liquor was the major interference species in the silicon content determination. The interference of acidic soluble lignin can be eliminated by hydrogen peroxide-nitric acid digestion method. The present method is not only simple, rapid, stable and less interferential, but also of good measurement precision and accuracy, with the relative standard deviations of 0.9%, and recoveries of 99.0%-102%. It is suitable for use in high silicon content of black liquor routine rapid analyses.