Effect of Dual Trigger In Vitro Fertilization and Intracytoplasmic Sperm Injection During the Gonadotropin-releasing Hormone-Antagonist Cycle on Final Oocyte Maturation and Cumulative Live Birth Rate in Women with Diminished Ovarian Reserve.

OBJECTIVE: It is well known that a dual trigger treatment can improve clinical outcomes of in vitro fertilization (IVF) in high or normal ovarian responders. However, it is not clear whether dual triggering also benefits patients with diminished ovarian reserve (DOR). The aim of this study was to investigate whether a dual trigger treatment of gonadotropin-releasing hormone (GnRH) agonist combined with human chorionic gonadotropin (hCG) for final follicular maturation improves the cumulative live birth rate (CLBR) during the GnRH-antagonist cycle in patients with DOR. METHODS: This retrospective study included patients with DOR who received a GnRH-antagonist protocol during IVF and intracytoplasmic sperm injection (IVF-ICSI) cycles at Peking University People's Hospital from January 1, 2017 through December 31, 2017. Oocyte maturation was triggered by GnRH combined with hCG (n=110) or hCG alone (n=71). Embryos were transferred on the third day after oocyte retrieval or during a subsequent freeze-thaw cycle. Patients were followed up for 3 years. RESULTS: The dual trigger treatment did not affect CLBR, which is an overall determinant of the success rate of assisted reproductive technology (ART). Women in the dual trigger group had significantly higher rates of fertilization than those in the hCG group (90.1% vs. 83.9%, P=0.040). CONCLUSION: Dual trigger with GnRH agonist and hCG did not improve CLBR in patients with DOR, but did slightly improve fertilization rate, oocyte count, and embryo quality.

A case report of spontaneous abortion caused by Brucella melitensis biovar 3.

BACKGROUND: Brucellosis is a worldwide zoonotic disease caused by Brucella spp. Brucella invades the body through the skin mucosa, digestive tract, and respiratory tract. However, only a few studies on human spontaneous abortion attributable to Brucella have been reported. In this work, the patient living in Shanxi Province in China who had suffered a spontaneous abortion was underwent pathogen detection and Brucella melitensis biovar 3 was identified. CASE PRESENTATION: The patient in this study was 22 years old. On July 16, 2015, she was admitted to Shanxi Grand Hospital, Shanxi Province, China because of one day of vaginal bleeding and three days of abdominal distension accompanied by fever after five months of amenorrhea. A serum tube agglutination test for brucellosis and blood culture were positive. At the time of discharge, she was prescribed oral doxycycline (100 mg/dose, twice a day) and rifampicin (600 mg/dose, once daily) for 6 weeks as recommended by the World Health Organization (WHO). No recurrence was observed during the six months of follow-up after the cessation of antibiotic treatment. CONCLUSIONS: This is the first reported case of miscarriage resulting from Brucella melitensis biovar 3 isolated from a pregnant woman who was infected through unpasteurized milk in China. Brucellosis infection was overlooked in the Maternity Hospital because of physician unawareness. Early recognition and prompt treatment of brucellosis infection are crucial for a successful outcome in pregnancy.

Protective effect of surface layer proteins isolated from four Lactobacillus strains on hydrogen-peroxide-induced HT-29 cells oxidative stress.

The objective of this study was to explore the antioxidant effect of the surface layer proteins (SLPs) and their mechanism. We investigated four SLPs which were extracted from L. casei zhang, L. rhamnosus, L. gasseri and L. acidophilus NCFM respectively using LiCl. The protective effect of SLPs on H2O2-induced HT-29 cells oxidative injury was investigated. As results, SLPs (100µg/mL) could significantly mitigate HT-29 cells cytotoxicity, improve the activities of total antioxidant capacity (T-AOC), catalase (CAT) and superoxide dismutase (SOD), decrease the contents of malondialdehyde (MDA) and lactate dehydrogenase (LDH), compared with H2O2-induced group (P<0.05). Furthermore, SLPs were also shown to attenuate the apoptosis rate (10.94-24.03%, P<0.01), suppress the elevation of intracellular reactive oxygen species (ROS) and calcium levels, restore mitochondrial membrane potential (MMP) and block the activation of apoptosis-related proteins of caspase-3 and caspase-9 (P<0.05). Considering all the parameters analyzed, we concluded that Lactobacillus SLPs play an essential role in the antioxidant capacity of HT-29 cells induced by H2O2, and the mechanism could be attributed to SLPs' ability to enhance the activity of the intracellular antioxidant enzyme system, reduce ROS accumulation and to inhibit apoptosis by regulating mitochondrial pathway.

Surface layer protein from Lactobacillus acidophilus NCFM inhibit intestinal pathogen-induced apoptosis in HT-29 cells.

Intestinal pathogens have been proposed to adhere to epithelial cells and cause apoptosis. This study was to investigate the inhibitory effects of surface layer protein (SLP, 46kDa) from Lactobacillus acidophilus NCFM on Escherichia coli and Salmonella-induced apoptosis in HT-29 cells and the mechanism of the inhibition was also studied. The SLP could alleviate the chromatin condensation caused by intestinal pathogens as observed under fluorescent microscope. Flow cytometry analysis showed that the SLP decreased E. coli and Salmonella-induced apoptosis by 46% and 48%, respectively. The SLP could also inhibit the mitochondrial membrane potential reduction and Ca2+ level increase in HT-29 cells. Furthermore, the activation of caspase-9 and caspase-3 induced by E. coli and Salmonella was significantly decreased by the addition of SLP. These results suggested that L. acidophilus NCFM SLP could protect HT-29 cells against intestinal pathogen-induced apoptosis through a mitochondria-mediated pathway. These findings may reveal a new method for the treatment of intestinal infection and provide a theoretical basis for the practical application of SLP in food, biological and pharmaceutical fields.

Murein hydrolase activity of surface layer proteins from Lactobacillus acidophilus against Escherichia coli.

The aim of this study was to investigate the murein hydrolase activities of the surface layer proteins (SLPs) from two strains of Lactobacillus acidophilus using zymography. The influence of these hydrolase activities on Escherichia coli ATCC 43893 was also evaluated by analysing their growth curve, cell morphology and physiological state. After the incubation of E. coli with SLPs, growth was inhibited, the number of viable cells was significantly reduced, examination by transmission electron microscopy showed that the cell wall was damaged and flow cytometry results indicated that the majority of the cells were sublethally injured. All of these results suggested that the SLPs of both L. acidophilus strains possessed murein hydrolase activities that were sublethal to E. coli cells.

Hydrophobicity of whey protein hydrolysates enhances the protective effect against oxidative damage on PC 12 cells.

The relationship between hydrophobicity and the protective effect of whey protein hydrolysates (WPHs) against oxidative stress was studied. Whey protein was first hydrolysed by pepsin and trypsin to obtain WPHs. After absorbed by macroporous adsorption resin DA201-C, three fractions named as M20, M40, and M60 were eluted by various concentrations of ethanol. The hydrophobicity showed a trend of increase from M20 to M60. Antioxidant ability test in vitro indicated that all the three components of WPHs displayed reasonably good antioxidant ability. Moreover, with the increase of hydrophobicity, antioxidant ability of WPHs improved significantly. Then rat pheochromocytoma line 12 (PC12) cells oxidative model was built to evaluate the suppression of oxidative stress of three components on PC12 cells induced by H2O2. Morphological alterations, cell viability, apoptosis rate, and intracellular antioxidase system tests all indicated that WPHs exert significant protection on PC cells against H2O2-induced damage. Among them, M60 had the highest protective effect by increasing 19·3% cell survival and reducing 28·6% cell apoptosis. These results suggested hydrophobicity of WPHs was contributing to the antioxidant ability and the protective effect against oxidative damage.

A novel cleaning process for industrial production of xylose in pilot scale from corncob by using screw-steam-explosive extruder.

Steam explosion is the most promising technology to replace conventional acid hydrolysis of lignocellulose for biomass pretreatment. In this paper, a new screw-steam-explosive extruder was designed and explored for xylose production and lignocellulose biorefinery at the pilot scale. We investigated the effect of different chemicals on xylose yield in the screw-steam-explosive extrusion process, and the xylose production process was optimized as followings: After pre-impregnation with sulfuric acid at 80 °C for 3 h, corncob was treated at 1.55 MPa with 9 mg sulfuric acid/g dry corncob (DC) for 5.5 min, followed by countercurrent extraction (3 recycles), decoloration (activated carbon dosage 0.07 g/g sugar, 75 °C for 40 min), and ion exchange (2 batches). Using this process, 3.575 kg of crystal xylose was produced from 22 kg corncob, almost 90 % of hemicellulose was released as monomeric sugar, and only a small amount of by-products was released (formic acid, acetic acid, fural, 5-hydroxymethylfurfural, and phenolic compounds were 0.17, 1.14, 0.53, 0.19, and 1.75 g/100 g DC, respectively). All results indicated that the screw-steam-explosive extrusion provides a more effective way to convert hemicellulose into xylose and could be an alternative method to traditional sulfuric acid hydrolysis process for lignocellulose biorefinery.

Characterization of surface layer proteins and its role in probiotic properties of three Lactobacillus strains.

The objective of this study was the characterization of the surface layer proteins (SLPs) and their functional role in the probiotic activity of Lactobacillus helveticus fb213, L. acidophilus fb116 and L. acidophilus fb214. SLPs were extracted and identified by SDS-PAGE, circular dichroism spectra and LC-MS analysis. The results revealed that the molecular masses of the three proteins were 49.7 kDa, 46.0 kDa and 44.6 kDa, respectively. The secondary structures and amino acid compositions of the three proteins were found to be similar. After removing SLPs, the survival of the three lactobacilli in simulated gastric and intestinal juices was reduced by 2-3log as compared with survival of the intact cells. And the adhesion ability of the three strains to HT-29 cells decreased by 61%, 65% and 92%, respectively. SLPs also inhibited the adhesion and invasion of Escherichia coli ATCC 43893 to HT-29 cells. These results suggest that SLPs are advantageous barriers for lactobacilli in the gastrointestinal tract, and these proteins help make it possible for lactobacilli to serve their probiotic functions.

Super-resolution scanning laser microscopy through virtually structured detection.

High resolution microscopy is essential for advanced study of biological structures and accurate diagnosis of medical diseases. The spatial resolution of conventional microscopes is light diffraction limited. Structured illumination has been extensively explored to break the diffraction limit in wide field light microscopy. However, deployable application of the structured illumination in scanning laser microscopy is challenging due to the complexity of the illumination system and possible phase errors in sequential illumination patterns required for super-resolution reconstruction. We report here a super-resolution scanning laser imaging system which employs virtually structured detection (VSD) to break the diffraction limit. Without the complexity of structured illumination, VSD provides an easy, low-cost and phase-artifact free strategy to achieve super-resolution in scanning laser microscopy.

In vivo optical coherence tomography of light-driven melanosome translocation in retinal pigment epithelium.

Optical coherence tomography (OCT) may revolutionize fundamental investigation and clinical management of age-related macular degeneration and other eye diseases. However, quantitative OCT interpretation is hampered due to uncertain sub-cellular correlates of reflectivity in the retinal pigment epithelium (RPE) and photoreceptor. The purpose of this study was twofold: 1) to test OCT correlates in the RPE, and 2) to demonstrate the feasibility of longitudinal OCT monitoring of sub-cellular RPE dynamics. A high resolution OCT was constructed to achieve dynamic imaging of frog eyes, in which light-driven translocation of RPE melanosomes occurred within the RPE cell body and apical processes. Comparative histological examination of dark- and light-adapted eyes indicated that the RPE melanin granule, i.e., melanosome, was a primary OCT correlate. In vivo OCT imaging of RPE melanosomes opens the opportunity for quantitative assessment of RPE abnormalities associated with disease, and enables longitudinal investigation of RPE kinetics correlated with visual function.

Isolation and identification of antioxidant peptides derived from whey protein enzymatic hydrolysate by consecutive chromatography and Q-TOF MS.

To isolate and identify antioxidant peptides from enzymatically hydrolysed whey protein, whey protein isolate was hydrolysed by different protease (trypsin, pepsin, alcalase 2·4L, promatex, flavourzyme, protease N). The hydrolysate generated by alcalase 2·4L had the highest antioxidant activities on 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals, superoxide radicals and in a linoleic acid peroxidation system induced by Fe2+. The IC50 values of DPPH and superoxide radical scavenging activities of the hydrolysate decreased significantly (6·89 and 38·88%, respectively) after treatment with macroporous adsorption resin. Seven different peptides showing strong antioxidant activities were isolated from the hydrolysate using consecutive chromatographic methods including gel filtration chromatography and high-performance liquid chromatography. The molecular mass and amino acids sequences of the purified peptides were determined using a Quadrupole time-of-flight mass spectrometer (Q-TOF MS). One of the antioxidative peptides, Trp-Tyr-Ser-Leu, displayed the highest DPPH radical scavenging activity (IC50=273·63 µm) and superoxide radical scavenging activity (IC50=558·42 µm). These results suggest that hydrolysates from whey proteins are good potential source of natural antioxidants.

In vivo confocal intrinsic optical signal identification of localized retinal dysfunction.

PURPOSE: The purposes of this study were to investigate the physiological mechanism of stimulus-evoked fast intrinsic optical signals (IOSs) recorded in dynamic confocal imaging of the retina, and to demonstrate the feasibility of in vivo confocal IOS mapping of localized retinal dysfunctions. METHODS: A rapid line-scan confocal ophthalmoscope was constructed to achieve in vivo confocal IOS imaging of frog (Rana pipiens) retinas at cellular resolution. In order to investigate the physiological mechanism of confocal IOS, comparative IOS and electroretinography (ERG) measurements were made using normal frog eyes activated by variable-intensity stimuli. A dynamic spatiotemporal filtering algorithm was developed to reject the contamination of hemodynamic changes on fast IOS recording. Laser-injured frog eyes were employed to test the potential of confocal IOS mapping of localized retinal dysfunctions. RESULTS: Comparative IOS and ERG experiments revealed a close correlation between the confocal IOS and retinal ERG, particularly the ERG a-wave, which has been widely used to evaluate photoreceptor function. IOS imaging of laser-injured frog eyes indicated that the confocal IOS could unambiguously detect localized (30 µm) functional lesions in the retina before a morphological abnormality is detectable. CONCLUSIONS: The confocal IOS predominantly results from retinal photoreceptors, and can be used to map localized photoreceptor lesion in laser-injured frog eyes. We anticipate that confocal IOS imaging can provide applications in early detection of age-related macular degeneration, retinitis pigmentosa, and other retinal diseases that can cause pathological changes in the photoreceptors.

Protective effect of whey protein hydrolysates against hydrogen peroxide-induced oxidative stress on PC12 cells.

The protective effect of whey protein hydrolysates (WPHs) against H(2)O(2)-induced oxidative damage on rat pheochromocytoma line 12 (PC12) cells was studied. Whey protein was hydrolyzed by pepsin and trypsin and purified by macrospore absorption resins. PC12 cells were pretreated with WPHs (from 369 to 1,980 Da) at different concentrations for 2 h, then washed and incubated with 100 µM H(2)O(2) in the presence of WPHs for another 24 h. With 100-400 µg WPH/ml the viable cells increased by 20-30 % when incubated with H(2)O(2) suggesting that they may play a role as antioxidant in foods.

Investigation of the hyper-reflective inner/outer segment band in optical coherence tomography of living frog retina.

This study is to test anatomic correlates, including connecting cilium (CC) and inner segment (IS) ellipsoid, to the hyper-reflective band visualized by optical coherence tomography (OCT) and commonly attributed to the photoreceptor inner/outer segment (IS/OS) junction. A line-scan OCT (LS-OCT) was constructed to achieve sub-cellular resolution (lateral: ≈ 2 µm; axial: ≈ 4 µm) of excised living frog retinas. An electro-optic phase modulator was employed for rapid and vibration-free phase modulation. Comparison of normalized distance measurements between LS-OCT images and histological images revealed that the dominant source of the signal reported as the IS/OS OCT band actually originates from the IS.

Comparative intrinsic optical signal imaging of wild-type and mutant mouse retinas.

Functional measurement is important for retinal study and disease diagnosis. Transient intrinsic optical signal (IOS) response, tightly correlated with functional stimulation, has been previously detected in normal retinas. In this paper, comparative IOS imaging of wild-type (WT) and rod-degenerated mutant mouse retinas is reported. Both 2-month and 1-year-old mice were measured. In 2-month-old mutant mice, time course and peak value of the stimulus-evoked IOS were significantly delayed (relative to stimulus onset) and reduced, respectively, compared to age matched WT mice. In 1-year-old mutant mice, stimulus-evoked IOS was totally absent. However, enhanced spontaneous IOS responses, which might reflect inner neural remodeling in diseased retina, were observed in both 2-month and 1-year-old mutant retinas. Our experiments demonstrate the potential of using IOS imaging for noninvasive and high resolution identification of disease-associated retinal dysfunctions. Moreover, high spatiotemporal resolution IOS imaging may also lead to advanced understanding of disease-associated neural remodeling in the retina.

In vivo confocal imaging of fast intrinsic optical signals correlated with frog retinal activation.

Using freshly isolated animal retinas, we have conducted a series of experiments to test fast intrinsic optical signals (IOSs) that have time courses comparable to electrophysiological kinetics. In this Letter, we demonstrate the feasibility of in vivo imaging of fast IOSs in intact frogs. A rapid line-scan confocal ophthalmoscope was constructed to achieve high-speed IOS recording. By rejecting out-of-focus background light, the line-scan confocal imager provided the resolution to differentiate individual photoreceptors in vivo. Rapid confocal imaging disclosed robust IOSs with time courses comparable to retinal electroretinogram kinetics. High-resolution IOS images revealed both positive (increasing) and negative (decreasing) light responses, with subcellular complexity.

Circular polarization intrinsic optical signal recording of stimulus-evoked neural activity.

Linear polarization intrinsic optical signal (LP-IOS) measurement can provide sensitive detection of neural activities in stimulus-activated neural tissues. However, the LP-IOS magnitude and signal-to-noise ratio (SNR) are highly correlated with the nerve orientation relative to the polarization plane of the incident light. Because of the complexity of orientation dependency, LP-IOS optimization and outcome interpretation are time consuming and complicated. In this study, we demonstrate the feasibility of circular polarization intrinsic optical signal (CP-IOS) measurement. Our theoretical modeling and experimental investigation indicate that CP-IOS magnitude and SNR are independent from the nerve orientation. Therefore, CP-IOS promises a practical method for polarization IOS imaging of complex neural systems.

Microlens array recording of localized retinal responses.

We designed a rapid functional imager for the parallel recording of localized intrinsic optical signals (IOSs). This imager used a microlens array (MLA)-based illuminator to deliver visible stimulus light and near-infrared (NIR) recording light simultaneously. The parfocal configuration of the stimulus and recording light illumination enabled confocal recording of the stimulus-evoked IOSs. Because the MLA stimulation/recording spots were widely separated on the retina, and only the photoreceptors within the MLA stimulation/recording spots were stimulated, the potential IOS cross talk effect among neighboring retinal areas was minimized. Our experiments revealed robust IOS activities tightly correlated with localized retinal responses.

Parallel optical monitoring of visual signal propagation from the photoreceptors to the inner retina layers.

Understanding of visual signal processing can benefit from simultaneous measurement of different types of retinal neurons working together. In this Letter, we demonstrate that intrinsic optical signal (IOS) imaging of frog retina slices allows simultaneous observation of stimulus-evoked responses propagating from the photoreceptors to the inner neurons. High-resolution imaging revealed robust IOSs at the photoreceptor, the inner plexiform, and the ganglion cell layers. While IOSs of the photoreceptor layer were mainly confined to the area directly stimulated by the visible light, IOSs of the inner retinal layers spread from the stimulus site into relatively large areas with a characteristic near-to-far time course.