Hippocampal Warburg effect Mediates Hydrogen Sulfide-Ameliorated Diabetes-Associated Cognitive Dysfunction: Involving Promotion of Hippocampal Synaptic Plasticity.

Our previous studies have reported that hydrogen sulfide (H2S) has ability to improve diabetes-associated cognitive dysfunction (DACD), but the exact mechanisms remain unknown. Recent research reveals that Warburg effect is associated with synaptic plasticity which plays a key role in cognition promotion. Herein, the present study was aimed to demonstrate whether hippocampal Warburg effect contributes to H2S-ameliorated DACD and further explore its potential mechanism. We found that H2S promoted the hippocampal Warburg effect and inhibited the OxPhos in the hippocampus of STZ-induced diabetic rats. It also improved the hippocampal synaptic plasticity in STZ-induced diabetic rats, as evidenced by the change of microstructures and the expression of different key-enzymes. Furthermore, inhibited hippocampal Warburg effect induced by DCA markedly abolished the improvement of H2S on synaptic plasticity in the hippocampus of STZ-induced diabetic rats. DCA blocked H2S-attenuated the cognitive dysfunction in STZ-induced diabetic rats, according to the Y-maze, Novel Objective Recognition, and Morris Water Maze tests. Collectively, these findings indicated that the hippocampal Warburg effect mediates H2S-ameliorated DACD by improving hippocampal synaptic plasticity.

Coleps shanghaiensis n. sp. challenges the validity of the genus Levicoleps (Cilophora, Prostomatida).

Coleps is a common genus of pelagic ciliates in freshwater and brackish water habitats. Classification and phylogeny of Coleps species are, however, still full of confusion. In this study, we investigated Coleps shanghaiensis n. sp., collected from a river in Shanghai, China, by living observation, protargol staining, and molecular methods. Coleps shanghaiensis is about 70-90 µm × 35-55 µm in size, has a barrel-shaped body with three posterior spines, and possesses 21-24 ciliary rows, each composed of two perioral dikinetids and 19-22 monokinetids, and six caudal cilia. In SSU rRNA gene phylogenies, C. shanghaiensis fell within the clade of subspecies of Levicoleps biwae, which questions the validity of the genus Levicoleps. Furthermore, the biogeography of the genus Coleps is discussed.

MicroRNA­17­5p alleviates sepsis­related acute kidney injury in mice by modulating inflammation and apoptosis.

Septic acute kidney injury (AKI) is considered as a severe and frequent complication that occurs during sepsis. Mounting evidence has confirmed the pivotal pathogenetic roles of microRNA (miRNA or miR) in sepsis­induced AKI; however, the role of miRNAs and their underlying mechanisms in sepsis­induced AKI have not been entirely understood. The present study aimed to elucidate the functions of special miRNAs during sepsis­induced AKI and its underlying mechanism. First, a number of differently expressed miRNAs was identified based on the microarray dataset GSE172044. Subsequently, lipopolysaccharide (LPS) was used to induce AKI in mice, and the role of miR­17­5p on AKI was clarified. Finally, the related molecular mechanisms were further examined by western blotting and immunohistochemical analysis. MiR­17­5p was found to be continuously decreased and reached the bottom at h 24 after AKI in mice. Functionally, injection of agomiR­17­5p could observably improve renal injury and survival rate, as well as inhibit inflammatory cytokine production and renal cell apoptosis in mice after AKI. On the contrary, injection of antagomiR­17­5p aggravated LPS­induced renal injury, inflammation and apoptosis in mice after AKI. Moreover, transforming growth factor ß receptor 2 (TGFßR2) was identified as a direct target of miR­17­5p, and its downstream phosphorylated Smad3 was also suppressed by miR­17­5p upregulation. Taken together, these results demonstrated that miR­17­5p overexpression may exhibit a beneficial effect by attenuating LPS­induced inflammation and apoptosis via regulating the TGFßR2/TGF­ß/Smad3 signaling pathway, indicating that miR­17­5p could act as a potential target for sepsis treatment.

Itaconate inhibits corticosterone-induced necroptosis and neuroinflammation via up-regulating menin in HT22 cells.

Corticosterone (CORT) damages hippocampal neurons as well as induces neuroinflammation. The tricarboxylic acid cycle metabolite itaconate has an anti-inflammatory role. Necroptosis is a form of programmed cell death, also known as inflammatory cell death. Menin is a multifunctional scaffold protein, which deficiency aggravates neuroinflammation. In this study, we explored whether itaconate inhibits CORT-induced neuroinflammation as well as necroptosis and further investigated the mediatory role of Menin in this protective effect of itaconate by using an exposure of CORT to HT22 cells (a hippocampal neuronal cell line). The viability of HT22 cells was examined by the cell counting kit 8 (CCK-8). The morphology of HT22 cells was observed by transmission electron microscope (TEM). The expressions of necroptosis-related proteins (p-RIP1/RIP1, p-RIP3/RIP3, and p-MLKL/MLKL) were evaluated by western blotting. The contents of inflammatory factors were detected by an enzyme-linked immunosorbent assay (ELISA) kit. Our results showed that CORT increases the contents of pro-inflammatory factors (IL-1ß, TNF-α) as well as decreases the contents of anti-inflammatory factors (IL-4, IL-10) in HT22 cells. We also found that CORT increases the expressions of necroptosis-related proteins (p-RIP1/RIP1, p-RIP3/RIP3, and p-MLKL/MLKL) and decreases the cell viability in HT22 cells, indicating that CORT induces necroptosis in HT22 cells. Itaconate improves CORT-induced neuroinflammation and necroptosis. Furthermore, itaconate upregulates the expression of Menin in CORT-exposed HT22 cells. Importantly, silencing Menin abolishes the antagonistic effect of itaconate on CORT-induced necroptosis and neuroinflammation. In brief, these results indicated that itaconate protects HT22 cells against CORT-induced neuroinflammation and necroptosis via upregulating Menin.

A new contribution to the raptorial ciliate genus Lacrymaria (Protista: Ciliophora): a brief review and comprehensive descriptions of two new species from Changjiang Estuary.

Ciliates serve as excellent indicators for water quality monitoring. However, their utilization is hindered by various taxonomic confusions. The ciliate genus Lacrymaria Bory de Saint-Vincent, 1824 is commonly found in different aquatic habitats, but its taxonomy has been sparsely investigated using state-of-the-art methods. This study investigated two new Lacrymaria species from Nanhui Wetland, Shanghai, China, using living observation, protargol staining, and molecular phylogeny methods. Lacrymaria songi sp. nov. is 180-340 × 20-25 µm in size and possesses 12-16 somatic kineties, 1 terminal contractile vacuole, 2 macronuclear nodules, and 2 types of rod-shaped extrusomes. Lacrymaria dragescoi sp. nov. is distinguished from its congeners by its cell size of 210-400 × 25-35 µm, 14-17 somatic kineties, 1 terminal contractile vacuole, 1 macronucleus, and 2 types of rod-shaped extrusomes. Phylogenetic analyses based on SSU rRNA gene sequences indicate that Lacrymariidae is monophyletic but Lacrymaria is not. Additionally, a brief review of the genus Lacrymaria is provided in this study. We suggest that L. bulbosa Alekperov, 1984, L. lanceolata Kahl, 1930, and L. ovata Burkovsky, 1970 be removed from the genus and propose Phialina lanceolata nov. comb. and Phialina ovata nov. comb. for the latter two. ZooBank registration: Present work: urn:lsid:zoobank.org:pub:CDFB1EBD-80BD-4533-B391-CEE89F62EDC4 Lacrymaria songi sp. nov.: urn:lsid:zoobank.org:act:417E7C2D-DAEC-4711-90BB-64AB3CD2F7D5 Lacrymaria dragescoi sp. nov.: urn:lsid:zoobank.org:act:8778D6B0-1F2E-473C-BE19-3F685391A40D.

A case report of diagnosis and dynamic monitoring of Listeria monocytogenes meningitis with NGS.

Listeria monocytogenes (LM) infections of the central nervous system are deadly and have vague symptoms. Traditional cerebro spinal fluid culture has a low positive rate, and because antibiotic use is common following therapy, it is more challenging to assess the response from pathogen content. In this case, a 66-year-old man who had a fever, a headache, and vomit was admitted to the hospital. He had diabetes, decline in thyroid function, and a history of pituitary tumor removal surgery. His initial treatment with ribavirin, ceftriaxone antibiotic, and moxifloxacin did not go well. Using two etiological tests (culture and metagenomic next-generation sequencing [mNGS]), his cerebrospinal fluid tested positively for LM. Ampicillin-sulbactam and meropenem were used as treatments once LM meningitis was identified. After treatment, his cerebrospinal fluid was assessed once more. Culture: negative; targeted next-generation sequencing (tNGS): positive and shows changes in the copy number of the LM. After 44 days of treatment, the patient finally stopped taking antibiotics, and the prognosis was good. Our study showed that mNGS and tNGS, as novel approaches for pathogen detection, are capable of identifying pathogens quickly, sensitively, and accurately, especially when there are few infections present (such as after antibiotic treatment). The two methods can be a powerful assistance for helping clinicians to choose the best course of action.

Human forebrain organoid-based multi-omics analyses of PCCB as a schizophrenia associated gene linked to GABAergic pathways.

Identifying genes whose expression is associated with schizophrenia (SCZ) risk by transcriptome-wide association studies (TWAS) facilitates downstream experimental studies. Here, we integrated multiple published datasets of TWAS, gene coexpression, and differential gene expression analysis to prioritize SCZ candidate genes for functional study. Convergent evidence prioritized Propionyl-CoA Carboxylase Subunit Beta (PCCB), a nuclear-encoded mitochondrial gene, as an SCZ risk gene. However, the PCCB's contribution to SCZ risk has not been investigated before. Using dual luciferase reporter assay, we identified that SCZ-associated SNPs rs6791142 and rs35874192, two eQTL SNPs for PCCB, showed differential allelic effects on transcriptional activities. PCCB knockdown in human forebrain organoids (hFOs) followed by RNA sequencing analysis revealed dysregulation of genes enriched with multiple neuronal functions including gamma-aminobutyric acid (GABA)-ergic synapse. The metabolomic and mitochondrial function analyses confirmed the decreased GABA levels resulted from inhibited tricarboxylic acid cycle in PCCB knockdown hFOs. Multielectrode array recording analysis showed that PCCB knockdown in hFOs resulted into SCZ-related phenotypes including hyper-neuroactivities and decreased synchronization of neural network. In summary, this study utilized hFOs-based multi-omics analyses and revealed that PCCB downregulation may contribute to SCZ risk through regulating GABAergic pathways, highlighting the mitochondrial function in SCZ.

Construction and validation of prognostic models in critically Ill patients with sepsis-associated acute kidney injury: interpretable machine learning approach.

BACKGROUND: Acute kidney injury (AKI) is a common complication in critically ill patients with sepsis and is often associated with a poor prognosis. We aimed to construct and validate an interpretable prognostic prediction model for patients with sepsis-associated AKI (S-AKI) using machine learning (ML) methods. METHODS: Data on the training cohort were collected from the Medical Information Mart for Intensive Care IV database version 2.2 to build the model, and data of patients were extracted from Hangzhou First People's Hospital Affiliated to Zhejiang University School of Medicine for external validation of model. Predictors of mortality were identified using Recursive Feature Elimination (RFE). Then, random forest, extreme gradient boosting (XGBoost), multilayer perceptron classifier, support vector classifier, and logistic regression were used to establish a prognosis prediction model for 7, 14, and 28 days after intensive care unit (ICU) admission, respectively. Prediction performance was assessed using the receiver operating characteristic (ROC) curve and decision curve analysis (DCA). SHapley Additive exPlanations (SHAP) were used to interpret the ML models. RESULTS: In total, 2599 patients with S-AKI were included in the analysis. Forty variables were selected for the model development. According to the areas under the ROC curve (AUC) and DCA results for the training cohort, XGBoost model exhibited excellent performance with F1 Score of 0.847, 0.715, 0.765 and AUC (95% CI) of 0.91 (0.90, 0.92), 0.78 (0.76, 0.80), and 0.83 (0.81, 0.85) in 7 days, 14 days and 28 days group, respectively. It also demonstrated excellent discrimination in the external validation cohort. Its AUC (95% CI) was 0.81 (0.79, 0.83), 0.75 (0.73, 0.77), 0.79 (0.77, 0.81) in 7 days, 14 days and 28 days group, respectively. SHAP-based summary plot and force plot were used to interpret the XGBoost model globally and locally. CONCLUSIONS: ML is a reliable tool for predicting the prognosis of patients with S-AKI. SHAP methods were used to explain intrinsic information of the XGBoost model, which may prove clinically useful and help clinicians tailor precise management.

Human forebrain organoids-based multi-omics analyses reveal PCCB's regulation on GABAergic system contributing to schizophrenia.

Identifying genes whose expression is associated with schizophrenia (SCZ) risk by transcriptome-wide association studies (TWAS) facilitates downstream experimental studies. Here, we integrated multiple published datasets of TWAS (including FUSION, PrediXcan, summary-data-based Mendelian randomization (SMR), joint-tissue imputation approach with Mendelian randomization (MR-JTI)), gene coexpression, and differential gene expression analysis to prioritize SCZ candidate genes for functional study. Convergent evidence prioritized Propionyl-CoA Carboxylase Subunit Beta ( PCCB ), a nuclear-encoded mitochondrial gene, as an SCZ risk gene. However, the PCCB ’s contribution to SCZ risk has not been investigated before. Using dual luciferase reporter assay, we identified that SCZ-associated SNP rs35874192, an eQTL SNP for PCCB , showed differential allelic effects on transcriptional activities. PCCB knockdown in human forebrain organoids (hFOs) followed by RNA-seq revealed dysregulation of genes enriched with multiple neuronal functions including gamma-aminobutyric acid (GABA)-ergic synapse, as well as genes dysregulated in postmortem brains of SCZ patients or in cerebral organoids derived from SCZ patients. The metabolomic and mitochondrial function analyses confirmed the deceased GABA levels resulted from reduced tricarboxylic acid cycle in PCCB knockdown hFOs. Multielectrode array recording analysis showed that PCCB knockdown in hFOs resulted into SCZ-related phenotypes including hyper-neuroactivities and decreased synchronization of neural network. In summary, this study utilized hFOs-based multi-omics data and revealed that PCCB downregulation may contribute to SCZ risk through regulating GABAergic system, highlighting the mitochondrial function in SCZ.

Silent information regulator 1 mediates H 2 S-inhibited chronic restraint stress-induced depressive-like behaviors by regulating hippocampal autophagy.

OBJECTIVES: Our previous study has demonstrated that hydrogen sulfide (H 2 S), a novel gasotransmitter, attenuates excessive autophagy and depressive-like behaviors in chronic restraint stress (CRS)-exposed rats, but the underlying molecular mechanism remains to be elucidated. Silent information regulator 1 (SIRT1), a deacetylase at the consumption of NAD+ plays an important regulatory role in depression. Hence, this study aimed to investigate whether SIRT1 mediates the protective effect of H 2 S on CRS-induced depressive-like behaviors by regulating hippocampal autophagy. METHODS: Adult male Sprague-Dawley (SD) rats were subjected to CRS (6 h × 28 days) to induce depression-like behavior. Rats were injected with sodium hydrosulfate (NaHS, 100 µmol/kg/d, i.p.), as a donor of H 2 S, alone or in combination with Sirtinol (a SIRT1 inhibitor; 10 nmol, i.c.v.) during CRS process. The depression-like characteristics of rats were assessed by the novelty-suppressed feeding test (NSFT), tail suspension test (TST), forced swimming test (FST) and open field test (OFT). The number of hippocampal autophagosomes was detected by transmission electron microscopy. The expressions of hippocampal autophagy-related proteins were measured by western blotting analysis. RESULTS: Sirtinol blocked the inhibitory effect of H 2 S on depressive-like behaviors in CRS-exposed rats according to NSFT, TST, FST and OFT. In addition, sirtinol reversed the protective response of H 2 S to CRS-induced excessive autophagy, as proved by the increases in the number of autophagosomes and the expression of Beclin-1 as well as a decrease in the expression of P62 in the hippocampus. CONCLUSION: These results indicated that SIRT1 contributes to the antidepressant-like function of H 2 S during CRS via reducing hippocampal autophagy.

Development and validation of a nomogram for predicting survival in patients with acute pancreatitis.

BACKGROUND: Acute pancreatitis (AP) is a complex and heterogeneous disease. We aimed to design and validate a prognostic nomogram for improving the prediction of short-term survival in patients with AP. METHODS: The clinical data of 632 patients with AP were obtained from the Medical Information Mart for Intensive Care (MIMIC)-IV database. The nomogram for the prediction of 30-day, 60-day and 90-day survival was developed by incorporating the risk factors identified by multivariate Cox analyses. RESULTS: Multivariate Cox proportional hazard model analysis showed that age (hazard ratio [HR]=1.06, 95% confidence interval [95% CI] 1.03-1.08, P<0.001), white blood cell count (HR=1.03, 95% CI 1.00-1.06, P=0.046), systolic blood pressure (HR=0.99, 95% CI 0.97-1.00, P=0.015), serum lactate level (HR=1.10, 95% CI 1.01-1.20, P=0.023), and Simplified Acute Physiology Score II (HR=1.04, 95% CI 1.02-1.06, P<0.001) were independent predictors of 90-day mortality in patients with AP. A prognostic nomogram model for 30-day, 60-day, and 90-day survival based on these variables was built. Receiver operating characteristic (ROC) curve analysis demonstrated that the nomogram had good accuracy for predicting 30-day, 60-day, and 90-day survival (area under the ROC curve: 0.796, 0.812, and 0.854, respectively; bootstrap-corrected C-index value: 0.782, 0.799, and 0.846, respectively). CONCLUSION: The nomogram-based prognostic model was able to accurately predict 30-day, 60-day, and 90-day survival outcomes and thus may be of value for risk stratification and clinical decision-making for critically ill patients with AP.

Microglia-containing human brain organoids for the study of brain development and pathology.

Microglia are resident immune cells in the central nervous system, playing critical roles in brain development and homeostasis. Increasing evidence has implicated microglia dysfunction in the pathogenesis of various brain disorders ranging from psychiatric disorders to neurodegenerative diseases. Using a human cell-based model to illuminate the functional mechanisms of microglia will promote pathological studies and drug development. The recently developed microglia-containing human brain organoids (MC-HBOs), in-vitro three-dimensional cell cultures that recapitulate key features of the human brain, have provided a new avenue to model brain development and pathology. However, MC-HBOs generated from different methods differ in the origin, proportion, and fidelity of microglia within the organoids, and may have produced inconsistent results. To help researchers to develop a robust and reproducible model that recapitulates in-vivo signatures of human microglia to study brain development and pathology, this review summarized the current methods used to generate MC-HBOs and provided opinions on the use of MC-HBOs for disease modeling and functional studies.

Two hypotrichs (Ciliophora, Hypotricha) from China: morphology and SSU rDNA sequence of Holosticha aestuarina nov. spec. and H. muuiensis Kim et al., 2017.

The morphology, four ontogenetic stages, and the phylogenetic relationships based on the small subunit RNA-gene of Holosticha aestuarina nov. spec. from the Yangtze River Estuary (Shanghai) were investigated. The new species differs from the congeners by the following combination of features: body size 160-196 × 27-36 µm in vivo, a vesicular structure containing one or two bean-shaped opaque particles, 24-32 adoral membranelles, 16-34 midventral pairs, 17-26 left marginal cirri, 22-32 right marginal cirri, six or seven transverse cirri, four dorsal kineties, and usually two macronuclear nodules. The anlage for the left marginal row of the proter very likely originates de novo (anterior portion) and from parental cirri (posterior portion). Further, we provide a morphological description of a Chinese population of H. muuiensis Kim et al., 2017, originally discovered in South Korea, indicating that it is confined to the Eastern Asia region. Its SSU rDNA sequence is identical with that of the type population and forms a clade with the available Holosticha sequences. By contrast, H. aestuarina nov. spec. is sister to the Holosticha + Uncinata clade, indicating that Uncinata is a subgenus of Holosticha.

Hydrogen sulfide prevents arecoline-induced neurotoxicity via promoting leptin/leptin receptor signaling pathway.

Arecoline, a major alkaloid of the areca nut, has potential toxicity to the nervous system. Our previous study reveals that the neurotoxicity of arecoline involves in inhibited endogenous hydrogen sulfide (H2 S) generation. Therefore, the present study investigated whether exogenous H2 S protects against arecoline-induced neurotoxicity and further explore the underlying mechanisms focusing on leptin/leptin receptor signaling pathway. The cell viability was measured by CCK-8 kit. The apoptosis were detected by Hoechst 33258 and Annexin V/PI (propidium iodide) staining. The protein expressions were determined by Western blot analysis. Our results demonstrated that NaHS, an exogenous H2 S donor, significantly increases the cell viability, decreases apoptosis ratio, and reduces caspase-3 activity as well as Bax/Bcl-2 ratio in PC12 cells exposed to arecoline, indicating the protection of H2 S against arecoline-induced cytotoxicity and apoptosis. Also, NaHS attenuated arecoline-induced endoplasmic reticulum (ER) stress, as evidenced by the decreases in the expressions of glucose-regulated protein 78 (GRP78), C/EBP homologous protein (CHOP), and Cleaved caspase-12. Meanwhile, NaHS promoted leptin/leptin receptor signaling pathway in arecoline-exposed PC12 cells, as illustrated by upregulations of leptin and leptin receptor expressions. Furthermore, leptin tA, an antagonist of leptin receptor, obviously abolished the inhibitory effects of NaHS on arecoline-induced cytotoxicity, apoptosis, and ER stress in arecoline-exposed PC12 cells. Taken together, these results suggested that H2 S prevents arecoline-induced neurotoxicity via enhancing the leptin/leptin receptor signaling pathway.

miR-146a-5p Attenuates Allergic Airway Inflammation by Inhibiting the NLRP3 Inflammasome Activation in Macrophages.

OBJECTIVE: Asthma is a common inflammatory respiratory disease with increasing incidence worldwide. This study aimed to investigate the mechanism of miR-146a-5p in reducing allergic airway inflammation by inhibiting NLRP3 inflammasome activation in macrophages. METHODS: Allergic mouse models were established by ovalbumin stimulation, and mice were treated with miR-146a-5p agomir and oe-TIRAP 3 h before OVA stimulation. The pathological changes of lung tissues were observed by hematoxylin-eosin staining. The airway hyperresponsiveness of mice were examined. The miR-146a-5p level was detected by RT-qPCR. The inflammatory cytokines (IL-18/TNF-α) and anti-inflammatory cytokine IL-10 levels in bronchoalveolar lavage fluid and serum IgE levels were examined by ELISA. Airway inflammation in mice was detected after miR-146a-5p overexpression. The levels of NLRP3/ASC/caspase1 proteins and macrophage M1/M2 surface markers in mouse lung tissues were examined using immunohistochemistry, Western blot, and flow cytometry. The targeting relationship between miR-146a-5p and TIRAP was verified by dual-luciferase assay. The p65 levels in the cytoplasm/nucleus of mouse lung tissue were measured. RESULTS: miR-146a-5p was downregulated in the lung tissues of allergic mice, and miR-146a-5p overexpression alleviated airway inflammation in asthmatic mice. miR-146a-5p suppressed NLRP3 inflammasome activation in macrophages of allergic mice, reduced NLRP3/ASC/caspase1 protein levels in lung tissues, blocked M1 polarization, and promoted M2 polarization. miR-146a-5p targeted TIRAP. TIRAP overexpression partially reversed the promoting effect of miR-146a-5p on M2 polarization. miR-146a-5p can inhibit the activation of the TIRAP/NF-κB pathway. CONCLUSION: miR-146a-5p inhibited NLRP3 inflammasome activation in macrophages in the lung tissue of allergic mice, prevented pro-inflammatory phenotype M1 polarization, and promoted anti-inflammatory phenotype M2 polarization by targeting the TIRAP/NF-κB pathway, thus alleviating airway inflammation in allergic asthma.

Taxonomy and SSU rRNA gene-based phylogeny of two new Euplotes species from China: E. chongmingensis n. sp. and E. paramieti n. sp. (Protista, Ciliophora).

BACKGROUND: The genus Euplotes Ehrenberg, 1830, one of the most complicated and confused taxa, contains about 160 nominal species. It was once proposed to be divided into four genera, two of which were proved to be non-monophyletic. At least 19 new species have been discovered in the past decade, implying that there is a large undiscovered diversity of this genus. RESULTS: The morphology of two new freshwater euplotid ciliates, Euplotes chongmingensis n. sp. and E. paramieti n. sp., isolated from Shanghai, China, were investigated using live observations, protargol staining, and Chatton-Lwoff silver staining method. Euplotes chongmingensis is characterized by its small size (40-50 × 25-35 µm), about 24 adoral membranelles, 10 frontoventral cirri, two marginal and two caudal cirri, eight dorsolateral kineties with 11-16 dikinetids in the mid-dorsolateral kinety and a double type of silverline system. Euplotes paramieti n. sp. is 180-220 × 110-155 µm in vivo and strongly resembles E. amieti but having a difference of 57 bp in their SSU rRNA gene sequences. Phylogenetic analyses based on SSU rRNA gene sequence data were used to determine the systematic positions of these new taxa. CONCLUSIONS: The description of two new freshwater taxa and their SSU rRNA gene sequences improve knowledge of biodiversity and enrich the database of euplotids. Furthermore, it offers a reliable reference for environmental monitoring and resource investigations.

Taxonomy and phylogeny of the freshwater tintinnid Tintinnopsis tubuformis Chiang, 1956 (Ciliophora, Oligotrichea) and a proposed synonymization of T. longa nom. corr. Chiang, 1956.

Tintinnid ciliates are traditionally identified by their loricae; however, increasing evidence indicates that some lorica features (e.g. its length, spiraled structures) are not reliable. The vast majority of tintinnids inhabit the marine pelagial; merely, about thirty species live in freshwater. In the present study, two morphotypes with similar lorica shapes and opening diameters but deviating lorica lengths were isolated from freshwater samples collected at different water temperatures near Chongming Island in the Yangtze Estuary, China. The specimens were studied in vivo and after protargol staining, and their phylogenetic placement was inferred from three ribosomal RNA markers; further, cell division was investigated in the short morphotype. Based on the original descriptions, the longer morphotype is identified as Tintinnopsis longa nom. corr. Chiang, 1956, and the shorter one as Tintinnopsis tubuformis Chiang, 1956. Despite distinct differences in the lorica lengths, the identity of the three molecular markers in both morphotypes suggests conspecificity, which is supported by overlapping ranges in the lorica opening diameters and the length-independent features of the somatic ciliary pattern (e.g. number of kineties). Hence, we synonymized T. longa nom. corr. with T. tubuformis and neotypified the later species.

Re-description and molecular phylogeny of the free-swimming peritrichs Hastatella radians Erlanger, 1890 and H. aesculacantha Jarocki & Jakubowska, 1927 (Ciliophora, Peritrichia) from China.

The present work investigated Hastatella radians Erlanger, 1890 (type species), and H. aesculacantha Jarocki & Jakubowska, 1927, isolated from Chongming Island, Shanghai, China, based on light microscopy observations of live individuals, silver staining and molecular phylogeny methods. Hastatella radians is characterized by its size (about 30-75 µm long, 25-70 µm wide), two girdles of ectoplasmic processes, infundibular polykinety 3 (P3) composed of two rows of unequal length and terminating beyond adstomal end of P2, 8-22 transverse silverlines between peristome and trochal band, and 5-9 between trochal band and scopula. The infraciliature of H. aesculacantha is described for the first time, and we improved its diagnosis: cell size about 25-52 × 20-41 µm in vivo; four girdles of ectoplasmic processes; P3 two-rowed, outer row much shorter than inner one; 5-7 silverlines between peristome and trochal band and four or five between trochal band and scopula. Phylogenetic analyses based on SSU rDNA sequences revealed that Hastatella is monophyletic and has a close relationship to Astylozoon enriquesi.

Improvement of autophagic flux mediates the protection of hydrogen sulfide against arecoline-elicited neurotoxicity in PC12 cells.

Arecoline, the most abundant alkaloid of the areca nut, induces toxicity to neurons. Hydrogen sulfide (H2S) is an endogenous gas with neuroprotective effects. We recently found that arecoline reduced endogenous H2S content in PC12 cells. In addition, exogenously administration of H2S alleviated the neurotoxicity of arecoline on PC12 cells. Increasing evidence has demonstrated the neuroprotective role of improvement of autophagic flux. Therefore, the aim of the present work is to explore whether improvement of autophagic flux mediates the protection of H2S against arecoline-caused neurotoxicity. Transmission electron microscope (TEM) for observation of ultrastructural morphology. Western blotting was used to detect protein expression of the related markers. Functional analysis contained LDH release assay, Hoechst 33,258 nuclear staining and flow cytometry were used to detect cytotoxicity and apoptosis. In the present work, we found that arecoline disrupted autophagy flux in PC12 cells as evidenced by accumulation of autophagic vacuoles, increase in LC3II/LC3I, and upregulation of p62 expression in PC12 cells. Notably, we found that sodium hydrosulfide (NaHS), the donor of H2S improved arecoline-blocked autophagy flux in PC12 cells. Furthermore, we found that blocking autophagic flux by chloroquine (CQ), the inhibitor of autophagy flux, antagonized the inhibitory role of NaHS in arecoline-induced cytotoxicity apoptosis and endoplasmic reticulum (ER) stress. In conclusion, H2S improves arecoline-caused disruption of autophagic flux to exert its protection against the neurotoxicity of arecoline.