Immune Deviation in the Decidua During Term and Preterm Labor.

The maternal-fetal immune disorder is considered to be an important factor of preterm birth (PTB); however, the underlying mechanism is still not fully understood. This study was designed to explore the innate and adaptive immune features in the decidua during term and preterm labor. Women delivered at term or preterm were classified into four groups: term not in labor (TNL, N=19), term in labor (TL, N=17), preterm not in labor (PNL, N=10), and preterm in labor (PIL, N=10). Decidua basalis and parietalis were collected and analyzed for macrophage subtypes (M1 and M2) as well as T helper 1 (Th1), Th2, Th17 and regulatory T (Treg) cells by flow cytometry and immunohistochemistry. Our results demonstrated significantly decreased frequencies of M2 cells and elevated M1/M2 ratio in the PIL group compared to that in the PNL group in both decidua basalis and parietalis, whereas no significant differences were found between the above two groups in both sites in terms of the polarization status of Th cells. On the contrary, macrophage subsets were comparable in the TL and TNL groups, whereas elevated Th1 percentages and Th1/Th2 ratio were observed in TL women compared to that in TNL women in the decidua. Interestingly, although the frequencies and ratios of Th17 and Treg were comparable among the four groups, the Th17/Treg ratios of these groups were significantly increased in decidua basalis than that in decidua parietalis. Collectively, the M1/M2 imbalance is associated with the breakdown of maternal-fetal immune tolerance during PTB, whereas the aberrant Th1/Th2 profile plays an important role in immune disorder during term labor. Moreover, Th17/Treg deviation is more remarkable in decidua basalis than in decidua parietalis.

G-CSF: A vehicle for communication between trophoblasts and macrophages which may cause problems in recurrent spontaneous abortion.

INTRODUCTION: The etiology of approximately half of patients with recurrent spontaneous abortion (RSA) has yet to be established. Granulocyte-colony stimulating factor (G-CSF) exerts a protective effect on pregnancy and its absence may lead to pregnancy failure. However, the effects and mechanisms of G-CSF activities have not been fully explored. Therefore, we aimed at evaluating whether a loss of G-CSF induces RSA by affecting cell communication at the maternal-foetal interface. METHODS: Villous and decidual tissues were obtained from participants and expression levels of G-CSF determined by qRT-PCR, Western blot and immunohistochemistry. G-CSF levels in trophoblasts were downregulated by siRNA. Exosomes were extracted from trophoblasts and co-cultured with macrophages. Molecular expression levels of key genes were determined by qRT-PCR and Western blot. Migration and proliferation of cells were evaluated by transwell and CCK8 assays. The RSA mice models were intraperitoneally administered with G-CSF to assess pregnancy outcomes and expression profiles of G-CSF as well as its receptor at the mother-foetal interface. RESULTS: Relative to the decidua, G-CSF was highly expressed in the villus, and expression levels were low in RSA tissues compared to normal tissues. Down-regulation of G-CSF in the trophoblast cell line (HTR-8/SVneo) by siRNA was associated with a decrease in cell activities. Trophoblast-derived exosomes inhibited the activation of the macrophage cell line (RAW264.7), whereas G-CSF free exosomes had no effects on macrophage activation. Intraperitoneal administration of G-CSF improved pregnancy outcomes in RSA mice and increased the amounts of G-CSF at the maternal-foetal interface. DISCUSSION: G-CSF levels were downregulated in villi of RSA patients. The absence of G-CSF impaired the proliferation as well as migration capacities of trophoblasts, and weakened the suppression of trophoblasts against macrophages. This implies that suppressed G-CSF levels may be a key factor in RSA occurrence. G-CSF decreased the rate of abortion in RSA mice, thus, it could be a treatment option for RSA patients.

Activated γδ T Cells With Higher CD107a Expression and Inflammatory Potential During Early Pregnancy in Patients With Recurrent Spontaneous Abortion.

Previous studies have reported the involvement of γδ T cells in recurrent spontaneous abortion (RSA); however, both pathogenic and protective effects were suggested. To interrogate the role of γδ T cells in RSA, peripheral blood from RSA patients and healthy women with or without pregnancy were analyzed for γδ T cells by flow cytometry (n = 9-11 for each group). Moreover, the decidua from pregnant RSA patients and healthy controls (RSA-P and HC-P group, respectively) was simultaneously stained for γδ T cells by immunohistochemistry (IHC) and bulk sequenced for gene expression. Our results demonstrated that the frequencies of peripheral γδ T cells and their subpopulations in RSA patients were comparable to that in healthy subjects, but the PD1 expression on Vδ2+ cells was increased in pregnant patients. Furthermore, peripheral Vδ2+ cells in RSA-P patients demonstrated significantly increased expression of CD107a, as compared to that in pregnant healthy controls. In addition, RSA-P patients had higher proportion of IL-17A-secreting but not IL-4-secreting Vδ2+ cells compared to the control groups. In decidua, an inflammatory microenvironment was also evident in RSA-P patients, in which CCL8 expression and the infiltration of certain immune cells were higher than that in the HC-P group, as revealed by transcriptional analysis. Finally, although the presence of γδ T cells in decidua could be detected during pregnancy in both RSA patients and healthy subjects by multicolor IHC analysis, the expression of CD107a on γδ T cells was markedly higher in the RSA-P group. Collectively, our results indicated that the increased activation, cytotoxicity, and inflammatory potential of peripheral and/or local γδ T cells might be responsible for the pathogenesis of RSA. These findings could provide a better understanding of the role of γδ T cells in RSA and shed light on novel treatment strategies by targeting γδ T cells for RSA patients.

Epidural analgesia during labor and its optimal initiation time-points: A real-world study on 400 Chinese nulliparas.

ABSTRACT: Recent research has suggested that 6 cm of cervical dilation should be the threshold for the active labor phase, and it has confirmed that epidural analgesia (EA) is a safe method of pain relief during labor. However, the evidence provided for these findings comes mainly from randomized controlled clinical trials (RCTs), which suffer from the limitation of real-world generalizability.To test the generalizability of the conclusions from these previous RCTs, we conducted a prospective cohort, real-world study (RWS) on 400 Chinese term nulliparas. A total of 200 of the participants (the EA group) received EA upon request. The participants in the EA group were further subdivided as follows according to their cervical dilation when the EA administration was initiated (CDE): [EA1 group (CDE < 3 cm), EA2 group (3 cm ≤ CDE < 6 cm), and EA3 group (CDE ≥ 6 cm)]. We compared the labor duration of the EA group versus the non-EA (NEA) group, and the NEA group versus the 3 EA subgroups. We also compared delivery outcomes between the EA and NEA groups.The median total labor duration for the EA group [676 (511-923) minutes] was significantly longer than that of the NEA group [514 (373-721) minutes] (P < 0.001). The median durations of both the first- and second-stages of labor for the EA group [600 (405-855) minutes, 68 (49-97) minutes] were longer than those of the NEA group [420 (300-630) minutes, 50 (32-85) minutes] (P < .001, P < .001)]. In addition, the median total labor durations in both the EA1 [720 (548-958) minutes] and EA2 groups [688 (534-926) minutes] were longer than in the NEA group (P < .001 and P < .001, respectively), and the first- and second-stage labor durations of these subgroups were similar to their total labor durations. A Cox regression analysis showed that EA was associated with longer first-stage labor [hazard ratio (HR) 0.55, 95% confidence interval (CI) 0.42-0.71, P < .001] and longer second-stage labor (HR 0.66, 95% CI 0.51-0.85, P = .001). The delivery modes and neonatal outcomes between the EA and NEA groups were not statistically different, however.Our findings suggest that EA administered before a cervical dilation of 6 cm may be associated with longer total, first-, and second-stage labor durations compared with no EA, while later EA administration is not. In addition, though EA prolongs labor duration, it does not impact delivery outcomes. These results confirm the significance of a 6 cm cervical dilation threshold in real-world labor settings.

The role of maternal-foetal interface inflammation mediated by NLRP3 inflammasome in the pathogenesis of recurrent spontaneous abortion.

INTRODUCTION: Approximately half of the recurrent spontaneous abortions (RSAs) that remain unidentified to date may be closely related to inflammation. Our previous study found excessive NLRP3 inflammasomes in RSA patients. Here, we investigated further the role of inflammasomes in the maternal-foetal interface of RSA patients. METHODS: Villous and decidual tissues were collected during uterine curettage. The trophoblast cell line TEV-1 was cultured with lipopolysaccharide (LPS) or low molecular weight heparin (LMWH), and then the macrophage cell line RAW264.7 was treated with trophoblast media. The expression and localisation of inflammasomes in tissues and cells were detected, and the migration and proliferation of cells were analysed. RESULTS: A significantly increased expression of inflammasomes was observed in RSA tissues compared with those in the normal group, and it was more obvious in villous tissues than in decidual tissues. In TEV-1 cells, after LPS stimulation, the expression of inflammasomes was increased, but the cell activity was decreased, whereas in RAW264.7, both expression of inflammasomes and cell activity were increased in the LPS group. In addition, LMWH could inhibit the action of LPS in above cells. DISCUSSION: In patients experiencing RSA, abnormal inflammatory response might be mediated by NLRP3 inflammasomes on the maternal-foetal interface, which may reduce trophoblast activity and promote macrophage activity, leading to early embryo implantation failure. LMWH is expected to treat RSA patients by blocking this process.

Variations of plasma D-dimer level at various points of normal pregnancy and its trends in complicated pregnancies: A retrospective observational cohort study.

D-Dimer (DD) is the smallest fragment of plasmin-mediated cleavage of fibrin. There is a progressive increase in DD concentration with advancing gestation in normal pregnancies, making the upper limit of 0.5 µg/ml used in non-pregnant population an unfavorable marker during pregnancy. Coagulation and fibrinolysis parameters are also markedly disturbed in pregnancies complicated by various pathologies.We designed this retrospective observational cohort study to investigate the trimester specific reference range for DD throughout normal pregnancy, and to compare the distribution of DD in third trimester healthy pregnancies and those complicated by preeclampsia (PE), severe preeclampsia (SPE), gestational diabetes mellitus (GDM), premature rupture of membranes (PROM) and preterm premature rupture of membranes (PPROM). In addition, we aimed to determine the diagnostic value of DD in PE and SPE.In this retrospective observational cohort study, 250 normal and 178 complicated pregnancies were included. Normal pregnancies included 88-first trimester, 101-second trimester and 61-third trimester pregnancies. Complicated pregnancy included 34 PE, 44 SPE, 32 GDM, 33 PROM, and 35 PPROM cases during the third trimester. Predefined exclusion criteria were used.The period of gestation (POG) accounted for 41.9% of the variance in DD, with strong correlation between the POG and DD. The trimester specific reference intervals were computed. The distribution for severe preeclampsia was statistically different compared to other categories in the third trimester. This exceptional distribution led to the generation of a receiver operating characteristic (ROC) curve with an area under curve of 0.828, attesting its possible role in predicting severe preeclampsia.We determined trimester specific reference intervals of DD. The role of DD has been explored, and it may be of diagnostic value in severe preeclampsia.

Electrophysiological phenotypes of synaptic transmission and neural network in hippocampal neurons of the α7-nAChR knockout mice.

It was reported that α7 nicotinic acetylcholine receptor (α7-nAChR) knockout (α7 KO) mice showed few functional phenotypes. The purpose of this study was to investigate the effect of α7 KO on the electrophysiological characteristics of hippocampus in mice. The effect of α7 KO on hippocampal CA3-CA1 synaptic transmission in mice was evaluated by standard extracellular field potential recordings. The electrophysiological phenotype of γ-aminobutyrate A receptors (GABAA-Rs) of single hippocampal neuron was detected by perforated patch-clamp recordings. The results showed that, the slope of field excitatory postsynaptic potential (fEPSP) and carbachol-induced theta oscillation were significantly decreased in the hippocampal CA1 neurons of α7 KO mice, compared with those of wild type mice. Under the treatment of GABAA-R agonist muscimol, the I-V curves of both the hippocampal CA1 and CA3 neurons of α7 KO mice shifted towards depolarizing direction obviously, compared with those of wild type mice. These results suggest that the hippocampal CA3-CA1 synaptic transmission in α7 KO mice was significantly impaired and GABAA-R maturation was significantly delayed, indicating that the deletion of α7-nAChR gene could significantly change the electrophysiological function of the hippocampus. The results may provide a new understanding of the role of α7-nAChR in hippocampal function and associated diseases.

Multifaceted spiral suture: A hemostatic technique in managing placenta praevia or accrete: A retrospective study.

Patients with total placenta previa and past history of cesarean delivery often experience overwhelming hemorrhage during childbirth. In order to control intraoperative and postoperative bleeding, we propose a novel multifaceted spiral suture of the lower uterine segment which directly sutures the bleeding site.To evaluate the efficacy and safety of multifaceted spiral suture, a retrospective study was conducted using data from 33 patients with total placenta praevia and caesarean history.All participants underwent multifaceted spiral suture and no patient experienced uncontrollable bleeding or underwent hysterectomy.The average blood loss of all patients involved was 1327.3 ±â€Š1244.1 mL. Five patients reported blood loss exceeding 3000 mL (15.15%), and the highest reached to 4000 mL. No complications such as fever, pyometra, synechiae, or uterine necrosis were observed. Three cases (3/33, 9.09%) reported hematuria in the first 3 days following surgery and spontaneous resolution were observed within 3 to 7 days following insertion of indwelling catheters. No complaints were received during 6-month follow-up visits.These findings suggest that multifaceted spiral suture is a practical, feasible, and promising technique in potentially minimizing postpartum bleeding and avoiding hysterectomy for patients with placenta praevia or accrete.

Evaluation of various equations for estimating renal function in elderly Chinese patients with type 2 diabetes mellitus.

BACKGROUND: The clinical assessment of kidney function based on the estimated glomerular filtration rate (GFR) in older patients remains controversial. This study evaluated the concordance and feasibility of using various creatinine-based equations for estimating GFR in elderly Chinese patients with type 2 diabetes mellitus (T2DM). METHODS: A cross-sectional analytical study was conducted in 21,723 older diabetic patients (≥60 years) based on electronic health records (EHR) for Minhang District, Shanghai, China. The concordance of chronic kidney disease (CKD) classification among different creatinine-based equations was assessed based on Kappa values, intraclass correlation coefficient (ICC) statistics, and the eGFR agreement between the equations was tested using Bland-Altman plots. The GFR was estimated using the Cockcroft-Gault (CG), Berlin Initiative Study 1 (BIS1), simplified Modification of Diet in Renal Disease (MDRD), MDRD modified for Chinese populations (mMDRD), chronic kidney disease epidemiology collaboration (CKD-EPI), CKD-EPI in Asians (CKD-EPI-Asia), and Ruijin equations. RESULTS: Overall, the proportion of CKD stages 3-5 (eGFR <60 mL/min/1.73 m2) was calculated as 28.9%, 39.1%, 11.8%, 8.4%, 14.3%, 11.5%, and 12.7% by the eGFRCG, eGFRBIS1, eGFRMDRD, eGFRmMDRD, eGFRCKD-EPI, eGFRCKD-EPI-Asia, and eGFRRuijin equations, respectively. The concordance of albuminuria and decreased eGFR based on the different equations was poor by both the Kappa (<0.2) and ICC (<0.4) statistics. The CKD-EPI-Asia equation resulted in excellent concordance with the CKD-EPI (ICC =0.931), MDRD (ICC =0.963), mMDRD (ICC =0.892), and Ruijin (ICC =0.956) equations for the classification of CKD stages, whereas the BIS1 equation exhibited good concordance with the CG equation (ICC =0.809). In addition, significant differences were observed for CKD stage 1 among all these equations. CONCLUSION: Accurate GFR values are difficult to estimate using creatinine-based equations in older diabetic patients. Kidney function is complex, and the staff need to be aware of the individualized consideration of other risk factors or markers of reduced renal function in clinical practice.

Effect of berberine on the ratio of high-molecular weight adiponectin to total adiponectin and adiponectin receptors expressions in high-fat diet fed rats.

OBJECTIVE: To assess the effects of berberine (BBR) on high-molecular weight (HMW) adiponectin and adiponectin receptors (adipoR1/adipoR2) expressions in high-fat (HF) diet fed rats. METHODS: Forty Wistar male rats were randomly assigned into a normal diet fed group and three HF diet (fat for 45% calories) fed groups (n=10 for each group). All rats underwent 12 weeks of feeding. After 4 weeks feeding, rats in the two of three HF diet fed groups were treated with 150 mg·kg-1·day-1 BBR (HF+LBBR group) and 380 mg·kg-1·day-1 BBR (HF+HBBR group) by gavage once a day respectively for the next 8 weeks while the rats in other groups treated with vehicle (NF+Veh and HF+Veh). Body weight and food intake were observed and recorded on daily basis. At the end of 12 weeks, the blood, liver, epididymal fat tissues and quadriceps femoris muscles were collected. Fasting insulin, plasma fasting glucose, serum free fatty acid (FFA), total adiponectin and HMW adiponectin levels were measured by enzyme linked immunosorbent assay method. Glucose tolerance test (GTT) and insulin tolerance test (ITT) were performed to determine the insulinsensitizing. Meanwhile the homeostasis model assessment (HOMA) method was used to determine insulin resistance (HOMA-IR). The expressions of adipoR1, adipoR2 and adenosine monophophate activated protein kinase (AMPK) phosphorylation level in skeletal muscle and liver tissue were detected by Western blot. Liver and kidney toxicity were evaluated during treatment. RESULTS: The body weight of rats in high- or low-dose BBR group reduced as well as HOMA-IR, FFA concentrations and fasting insulin levels decreased compared with HF+Veh group (P<0.05). BBR also increased the ratio of HMW to total adiponectin in high fat-fed rats compared with rats in the HF+Veh group. High- and low-dose BBR increased adipoR1 expression in skeletal muscle by over 6- and 2-fold (P<0.05), respectively, and high-dose BBR also increased adipoR2 expression in liver tissue by over 2-fold (P<0.05). BBR significantly increased AMPK phosphorylation in HF diet rats compared with normal diet rats (P<0.05). The ratio of HMW to total adiponectin was inversely correlated with HOMA-IR (r=-0.52, P=0.001). Meantime, no liver and kidney toxicity was found in high fat-fed rats that treated by BBR. CONCLUSION: Berberine may improve insulin resistance by increasing the expression of adiponectin receptors and the ratio of HMW to total adiponectin.

Suppression of synaptic plasticity by fullerenol in rat hippocampus in vitro.

Fullerenol, a water-soluble fullerene derivative, has attracted much attention due to its bioactive properties, including the antioxidative properties and free radical scavenging ability. Due to its superior nature, fullerenol represents a promising diagnostic, therapeutic, and protective agent. Therefore, elucidation of the possible side effects of fullerenol is important in determining its potential role. In the present study, we investigated the acute effects of 5 µM fullerenol on synaptic plasticity in hippocampal brain slices of rats. Incubation with fullerenol for 20 minutes significantly decreased the peak of paired-pulse facilitation and long-term potentiation, indicating that fullerenol suppresses the short- and long-term synaptic plasticity of region I of hippocampus. We found that fullerenol depressed the activity and the expression of nitric oxide (NO) synthase in hippocampus. In view of the important role of NO in synaptic plasticity, the inhibition of fullerenol on NO synthase may contribute to the suppression of synaptic plasticity. These findings may facilitate the evaluation of the side effects of fullerenol.

Identifying inhibitory compounds in lignocellulosic biomass hydrolysates using an exometabolomics approach.

BACKGROUND: Inhibitors are formed that reduce the fermentation performance of fermenting yeast during the pretreatment process of lignocellulosic biomass. An exometabolomics approach was applied to systematically identify inhibitors in lignocellulosic biomass hydrolysates. RESULTS: We studied the composition and fermentability of 24 different biomass hydrolysates. To create diversity, the 24 hydrolysates were prepared from six different biomass types, namely sugar cane bagasse, corn stover, wheat straw, barley straw, willow wood chips and oak sawdust, and with four different pretreatment methods, i.e. dilute acid, mild alkaline, alkaline/peracetic acid and concentrated acid. Their composition and that of fermentation samples generated with these hydrolysates were analyzed with two GC-MS methods. Either ethyl acetate extraction or ethyl chloroformate derivatization was used before conducting GC-MS to prevent sugars are overloaded in the chromatograms, which obscure the detection of less abundant compounds. Using multivariate PLS-2CV and nPLS-2CV data analysis models, potential inhibitors were identified through establishing relationship between fermentability and composition of the hydrolysates. These identified compounds were tested for their effects on the growth of the model yeast, Saccharomyces. cerevisiae CEN.PK 113-7D, confirming that the majority of the identified compounds were indeed inhibitors. CONCLUSION: Inhibitory compounds in lignocellulosic biomass hydrolysates were successfully identified using a non-targeted systematic approach: metabolomics. The identified inhibitors include both known ones, such as furfural, HMF and vanillin, and novel inhibitors, namely sorbic acid and phenylacetaldehyde.

Pichia anomala 29X: a resistant strain for lignocellulosic biomass hydrolysate fermentation.

To efficiently use lignocellulosic biomass hydrolysates as fermentation media for bioethanol production, besides being capable of producing significant amount of ethanol, the fermenting host should also meet the following two requirements: (1) resistant to the inhibitory compounds formed during biomass pretreatment process, (2) capable of utilizing C5 sugars, such as xylose, as carbon source. In our laboratory, a screening was conducted on microorganisms collected from environmental sources for their tolerance to hydrolysate inhibitors. A unique resistant strain was selected and identified as Pichia anomala (Wickerhamomyces anomalus), deposited as CBS 132101. The strain is able to produce ethanol in various biomass hydrolysates, both with and without oxygen. Besides, the strain could assimilate xylose and use nitrate as N source. These physiological characteristics make P. anomala an interesting strain for bioethanol production from lignocellulosic biomass hydrolysates.

[Construction and sequence analysis of a normalized full-length cDNA library of Dendrobium officinale].

OBJECTIVE: In order to obtain functional genes, a normalized stems cDNA library was constructed from medicinal plant Dendrobium officinale. METHOD: SMART (switching mechanism at 5' end of RNA transcript) cDNA synthesis combined with DSN (duplex-specific nuclease) normalization was applied to construct the normalized full-length cDNA library of D. officinale. RESULT: The titer of cDNA library was about 1.3 x 10(6) cfu x mL(-1) and the average insertion size was about 1.5 kb with high recombination rate (93.9%). Random selected 163 positive clones were sequenced at single side. Bio-information analysis indicated that 147 from 150 high-quality unique sequences matched corresponding homologous proteins, and they participated in various biological processes based on GO (gene ontology). There were 8 clones with complete coding sequence, which presumed to be full-length genes. CONCLUSION: These results showed preliminarily that we successfully constructed a normalized full-length cDNA library of D. officinale which could be used to screen the functional genes related to metabolic pathways of medicinal ingredients.

Analysis of oligosaccharides in lignocellulosic biomass hydrolysates by high-performance anion-exchange chromatography coupled with mass spectrometry (HPAEC-MS).

The carbohydrate composition of lignocellulosic biomass hydrolysates is highly complex. High performance anion exchange chromatography coupled with pulsed amperometric detection (HPAEC-PAD), a widely used method for carbohydrate analysis, provides limited chemical information on the detected peaks. To improve the detection and increase the chemical information of the carbohydrates, HPAEC was coupled with mass spectrometry (MS). Using a pooled hydrolysate sample, it was shown that HPAEC-MS can separate and detect many oligosaccharides in one experimental run based on retention time and mass. The method was validated on its linearity, reproducibility and response factors. The analysis of a group of different biomass hydrolysates revealed that remaining disaccharides was the bottleneck of the hydrolysis process. As an analytical tool, HPAEC-MS provides information for the improvement of hydrolysate pretreatment method and enzyme cocktail quality. Besides, the consumption ability of microbial host strains for various mono- and oligosaccharides in hydrolysates can be assessed.

Pervaporation of ethanol from lignocellulosic fermentation broth.

Pervaporation can be applied in ethanol production from lignocellulosic biomass. Hydrophobic pervaporation, using a commercial PDMS membrane, was employed to concentrate the ethanol produced by fermentation of lignocellulosic hydrolysate. To our knowledge, this is the first report describing this. Pervaporation carried out with three different lignocellulosic fermentation broths reduced the membrane performance by 17-20% as compared to a base case containing only 3 wt.% ethanol in water. The membrane fouling caused by these fermentation broths was irreversible. Solutions containing model lignocellulosic components were tested during pervaporation at the same conditions. A total flux decrease of 12-15%, as compared to the base case, was observed for each component except for furfural. Catechol was found to be most fouling component whereas furfural permeated through the membrane and increased the total flux. The membrane selectivity increased in the presence of fermentation broth but remained unchanged for all selected components.

Exometabolomics approaches in studying the application of lignocellulosic biomass as fermentation feedstock.

Lignocellulosic biomass is the future feedstock for the production of biofuel and bio-based chemicals. The pretreatment-hydrolysis product of biomass, so-called hydrolysate, contains not only fermentable sugars, but also compounds that inhibit its fermentability by microbes. To reduce the toxicity of hydrolysates as fermentation media, knowledge of the identity of inhibitors and their dynamics in hydrolysates need to be obtained. In the past decade, various studies have applied targeted metabolomics approaches to examine the composition of biomass hydrolysates. In these studies, analytical methods like HPLC, RP-HPLC, CE, GC-MS and LC-MS/MS were used to detect and quantify small carboxylic acids, furans and phenols. Through applying targeted metabolomics approaches, inhibitors were identified in hydrolysates and their dynamics in fermentation processes were monitored. However, to reveal the overall composition of different hydrolysates and to investigate its influence on hydrolysate fermentation performance, a non-targeted metabolomics study needs to be conducted. In this review, a non-targeted and generic metabolomics approach is introduced to explore inhibitor identification in biomass hydrolysates, and other similar metabolomics questions.

Concentration-dependent effects of fullerenol on cultured hippocampal neuron viability.

BACKGROUND: Recent studies have shown that the biological actions and toxicity of the water-soluble compound, polyhydroxyfullerene (fullerenol), are related to the concentrations present at a particular site of action. This study investigated the effects of different concentrations of fullerenol on cultured rat hippocampal neurons. METHODS AND RESULTS: Fullerenol at low concentrations significantly enhanced hippocampal neuron viability as tested by MTT assay and Hoechst 33342/propidium iodide double stain detection. At high concentrations, fullerenol induced apoptosis confirmed by Comet assay and assessment of caspase proteins. CONCLUSION: These findings suggest that fullerenol promotes cell death and protects against cell damage, depending on the concentration present. The concentration-dependent effects of fullerenol were mainly due to its influence on the reduction-oxidation pathway.